Merge dev into main: v3.6.7 release

- Add advanced filename template placeholders: {track_raw}, {disc_raw}, {date},
  formatted numbers {track:N}/{disc:N}, and date formatting {date:%Y-%m-%d}
  with strftime-to-Go layout conversion and robust date parser
- Pass date/release_date metadata to filename builder in all providers
  (Amazon, Qobuz, Tidal, YouTube, extensions) and Flutter download queue
- Detect ARM32-only / low-RAM Android devices at startup and reduce image
  cache size and disable overscroll effects for smoother experience
- Make artist screen selection bar responsive: compact stacked layout on
  narrow screens or large text scale; add quality picker before track download
- Add advanced tags toggle in download settings filename format editor
- Fix ICU plural syntax in DE/ES/PT/RU translations (one {}=1{...} -> one {...})
- Add filenameShowAdvancedTags l10n strings (EN, ID) and regenerate dart files
- Fix featured-artist regex: remove '&' from split separators
- Add Go filename template tests (filename_test.go)
- Add GitHub Pages workflow and static project site

.github/FUNDING.yml

@@ -1,4 +1,3 @@
 github: zarzet
 ko_fi: zarzet
-buy_me_a_coffee: zarzet
 

.github/workflows/auto-tag.yml

@@ -15,7 +15,7 @@ jobs:
     
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 2  # Need previous commit to compare
 

.github/workflows/pages.yml

@@ -0,0 +1,44 @@
+name: Deploy to GitHub Pages
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - 'site/**'
+      - '.github/workflows/pages.yml'
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  pages: write
+  id-token: write
+
+concurrency:
+  group: pages
+  cancel-in-progress: true
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Setup Pages
+        uses: actions/configure-pages@v5
+
+      - name: Upload artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: site
+
+  deploy:
+    needs: build
+    runs-on: ubuntu-latest
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4

.github/workflows/release.yml

@@ -60,23 +60,23 @@ jobs:
           df -h
 
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Java
-        uses: actions/setup-java@v4
+        uses: actions/setup-java@v5
         with:
           distribution: "temurin"
           java-version: "17"
 
       - name: Setup Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
-          go-version: "1.21"
+          go-version: "1.26"
           cache-dependency-path: go_backend/go.sum
 
       # Cache Gradle for faster builds
       - name: Cache Gradle
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: |
             ~/.gradle/caches
@@ -158,7 +158,7 @@ jobs:
           ls -la
 
       - name: Upload APK artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: android-apk
           path: build/app/outputs/flutter-apk/SpotiFLAC-*.apk
@@ -169,17 +169,17 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@v6
         with:
-          go-version: "1.21"
+          go-version: "1.26"
           cache-dependency-path: go_backend/go.sum
 
       # Cache CocoaPods
       - name: Cache CocoaPods
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         with:
           path: ios/Pods
           key: pods-${{ runner.os }}-${{ hashFiles('ios/Podfile.lock') }}
@@ -295,7 +295,7 @@ jobs:
           fi
 
       - name: Upload IPA artifact
-        uses: actions/upload-artifact@v4
+        uses: actions/upload-artifact@v6
         with:
           name: ios-ipa
           path: build/ios/ipa/SpotiFLAC-*.ipa
@@ -308,7 +308,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Extract changelog for version
         id: changelog
@@ -338,13 +338,13 @@ jobs:
           cat /tmp/changelog.txt
 
       - name: Download Android APK
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v7
         with:
           name: android-apk
           path: ./release
 
       - name: Download iOS IPA
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v7
         with:
           name: ios-ipa
           path: ./release
@@ -385,7 +385,7 @@ jobs:
           cat /tmp/release_body.txt
 
       - name: Create Release
-        uses: softprops/action-gh-release@v1
+        uses: softprops/action-gh-release@v2
         with:
           tag_name: ${{ needs.get-version.outputs.version }}
           name: SpotiFLAC ${{ needs.get-version.outputs.version }}
@@ -403,16 +403,16 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Download Android APK
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v7
         with:
           name: android-apk
           path: ./release
 
       - name: Download iOS IPA
-        uses: actions/download-artifact@v4
+        uses: actions/download-artifact@v7
         with:
           name: ios-ipa
           path: ./release

CHANGELOG.md

@@ -1,6 +1,566 @@
 # Changelog
 
-## [3.3.0] - 2026-01-31
+## [3.6.7] - 2026-02-13
+
+### Added
+
+- "Advanced Filename Templates" - new placeholders for custom track/disc formatting and date patterns
+  - `{track_raw}` and `{disc_raw}` - unpadded raw numbers
+  - `{track:N}` and `{disc:N}` - zero-padded to N digits (e.g. `{track:02}` → `01`)
+  - `{date}` - full release date from metadata
+  - `{date:%Y-%m-%d}` - date formatting with strftime patterns
+  - "Show advanced tags" toggle in Settings > Download > Filename Format to reveal these placeholders
+- Low-RAM / ARM32-only device profiling - detects constrained devices at startup and reduces image cache (120 items / 24 MiB) and disables overscroll effects for smoother performance
+- Responsive selection bar on artist screen - switches to compact stacked layout on narrow screens (< 430dp) or large text scale (> 1.15x)
+- Quality picker dialog before downloading individual tracks from artist screen (when "Ask quality before download" is enabled)
+- Project website with GitHub Pages deployment workflow
+  - Mobile burger menu navigation for all site pages
+- Go filename template test suite
+
+### Fixed
+
+- Fixed ICU plural syntax errors in DE, ES, PT, RU translations - incorrect `=1` clause was causing missing plural forms
+- Fixed featured-artist regex incorrectly splitting on `&` character (e.g. "Simon & Garfunkel" was being split) - removed `&` from separator pattern
+- Fixed `{date}` placeholder not working in filename templates - release date was not being passed to the template builder across all providers (Amazon, Qobuz, Tidal, YouTube, extensions)
+
+### Changed
+
+- Improved Go backend metadata handling - filename builder now supports fallback metadata keys and automatic type conversion for more robust template rendering
+- Extension providers now pass full metadata set to filename builder (track, disc, year, date, release_date)
+- Updated translations: added filename advanced tags strings (EN, ID), regenerated all locale dart files
+- Updated app screenshot assets
+
+---
+
+## [3.6.6] - 2026-02-12
+
+### Added
+
+- "Filter Contributing Artists in Album Artist" setting - strips featured/contributing artists from Album Artist metadata tag
+- Library scan notifications (Android and iOS) - shows progress, completion, failure, and cancellation status
+- Collapsible "Artist Name Filters" section in download settings UI
+
+### Fixed
+
+- Fixed downloads not working on iOS - missing `downloadByStrategy` and `downloadFromYouTube` method channel handlers in AppDelegate.swift
+- Fixed extended metadata (genre, label, copyright) lost during service fallback (e.g. Tidal unavailable, falls back to Qobuz) - Go backend now enriches metadata from Deezer by ISRC before download and preserves it through the fallback chain
+- Fixed local library showing incorrect "16-bit" quality label for lossy formats (MP3, Opus) - now displays actual bitrate (e.g. "MP3 320kbps")
+- Fixed inaccurate Opus/Vorbis duration calculation (e.g. 4:11 showing as 8:44) - now reads granule position from last Ogg page for precise duration
+- Fixed MP3 duration/bitrate inaccuracy for VBR files - added Xing/Info and VBRI header parsing with MPEG2/2.5 bitrate table support
+- Fixed Track Metadata screen showing scan date instead of file date for local library items
+- Fixed SAF content URI paths displayed as raw `content://` strings in Track Metadata - now shows human-readable paths
+
+### Changed
+
+- Removed legacy iOS download handlers (`downloadTrack`, `downloadWithFallback`, `downloadFromYouTube`) - iOS now uses `downloadByStrategy` only
+- Updated translations from Crowdin (all 14 languages)
+
+---
+
+## [3.6.5] - 2026-02-10
+
+### Highlights
+
+- **Audio Format Conversion**: Convert between FLAC, MP3, and Opus directly from Track Metadata screen with full metadata and cover art preservation
+- **PC v7.0.8 Backend Merge**: Adopts several Go backend improvements from SpotiFLAC PC v7.0.8 including Amazon encrypted stream support, SpotFetch metadata fallback, and Qobuz API update
+- **Amazon Music Re-enabled**: Amazon provider back in service with new API
+
+### Added
+
+- "Use Primary Artist Only" setting: strips featured artists from folder names (e.g. "Justin Bieber, Quavo" becomes "Justin Bieber") for cleaner folder organization
+  - Supports separators: `, ` `;` `&` `feat.` `ft.` `featuring` `with` `x`
+  - Available in Settings > Download > below "Use Album Artist for folders"
+- Audio format conversion from Track Metadata screen
+  - Convert between FLAC, MP3, and Opus formats (any direction)
+  - Selectable bitrate: 128k, 192k, 256k, 320k
+  - Full metadata and cover art preservation during conversion
+  - Confirmation dialog before converting (original file deleted after)
+  - SAF storage support: copies to temp, converts, writes back via SAF
+  - Download history automatically updated with new file path
+- Unified download request contract (`DownloadRequestPayload`) for all providers/flows
+  - Includes full superset fields: lyrics mode, genre/label/copyright, provider IDs, SAF params, cover/quality settings
+  - Added strategy flags in payload: `use_extensions`, `use_fallback`
+- New Go unified router entrypoint: `DownloadByStrategy(requestJSON)`
+  - Routing priority: YouTube service -> extension fallback -> built-in fallback -> direct service
+- New Android method channel handler: `"downloadByStrategy"` -> `Gobackend.downloadByStrategy(...)`
+- SpotFetch metadata fallback integration for Spotify-blocked regions
+  - New backend client for `spotify.afkarxyz.fun/api`
+  - Automatic fallback in Spotify metadata fetch path when primary source fails
+- Lyrics extraction now supports MP3 (ID3v2) and Opus/OGG (Vorbis comments) in addition to FLAC
+  - Includes heuristic detection of lyrics stored in Comment fields
+- Edit Metadata now supports manual cover selection (pick/replace cover image) and embeds it into audio tags on save
+- Save Lyrics now shows an immediate in-progress snackbar (`Saving lyrics...`) so users know the operation has started
+
+### Changed
+
+- Merged several Go backend improvements from SpotiFLAC PC v7.0.8: Amazon new API with encrypted stream/decryption support, SpotFetch metadata fallback for Spotify-blocked regions, multi-format lyrics extraction (MP3/Opus/OGG), Qobuz Jumo API update.
+- Download queue execution now builds one payload and uses a single bridge entrypoint (`PlatformBridge.downloadByStrategy`) instead of branching into multiple bridge methods
+- Dart `downloadByStrategy` now sends a single request to Go (`downloadByStrategy` channel); routing concern is centralized in Go backend
+- Legacy Dart bridge methods (`downloadTrack`, `downloadWithFallback`, `downloadWithExtensions`, `downloadFromYouTube`) are now thin wrappers and marked `@Deprecated`
+- Qobuz downloader updated to latest Jumo API contract (`/get` endpoint, required headers)
+- Amazon download flow now returns `decryption_key` from Go and performs decryption in Flutter (local file + SAF paths)
+- Amazon now uses the new `amazon.afkarxyz.fun` API flow (ASIN-based track endpoint + legacy fallback) with encrypted stream support
+- Amazon ASIN extraction rewritten with robust URL/query-param parsing and regex fallback
+- Amazon provider re-enabled in download service picker and download settings (alongside Tidal, Qobuz, and YouTube picker flow)
+- Track Metadata cover UI now refreshes from the embedded file after Edit Metadata/Re-enrich, so the displayed art matches actual file tags
+- Edit Metadata cover section moved to the top of the form and now previews current embedded cover before replacement (plus selected replacement preview)
+- Edit Metadata cover preview enlarged (120px to 160px) with shadow, side-by-side layout for current vs selected cover, and label repositioned below image
+
+### Fixed
+
+- Fixed lyrics mode "External .LRC" still embedding lyrics into metadata - `lyrics_mode` was not being sent to Go backend for single-service downloads and YouTube provider, causing Go to default to "embed"
+- Fixed `flutter_local_notifications` v20 breaking changes - migrated all `initialize()`, `show()`, and `cancel()` calls from positional parameters to named parameters
+- Fixed SAF duplicate folder bug: concurrent batch downloads creating empty folders with `(1)`, `(2)`, `(3)` suffixes - added synchronized lock to `ensureDocumentDir` in Kotlin with duplicate detection and cleanup
+- Track Metadata lyrics section now hides "Embed Lyrics" when lyrics are already embedded in file, preventing redundant embed attempts
+- Fixed lyrics embed path to support FLAC/MP3/Opus consistently (including SAF files) without forcing unsupported parser paths
+- Inconsistent parameter parity across download paths
+  - `downloadWithExtensions` now carries `copyright`
+  - YouTube path now carries `embed_max_quality_cover` and metadata parity fields
+- Inconsistent success response metadata between direct/fallback flows
+  - Added shared Go response builder for `DownloadTrack` and `DownloadWithFallback`
+  - Success responses now consistently include `genre`, `label`, `copyright`, and `lyrics_lrc`
+- YouTube success response now also includes extended metadata fields (`cover_url`, `genre`, `label`, `copyright`) for parity with other providers
+- Fixed `Save Lyrics` crash on Android (`java.lang.Integer cannot be cast to java.lang.Long`) by normalizing `duration_ms` channel argument as `Number -> Long`
+- Fixed FLAC Re-enrich cover edge case where metadata could be written without cover when temp cover file creation failed; FLAC cover embed now uses in-memory bytes and verifies cover after write
+- Fixed FLAC picture-block embed robustness by detecting image MIME via magic bytes (JPEG/PNG/GIF/WEBP) instead of relying on filename extension
+- Fixed MP3/Opus metadata rewrite flows to preserve existing embedded cover when no new cover is available
+- Fixed Library tab cover not updating after manual cover edit/re-embed for downloaded tracks
+  - Queue/Library now prefers embedded cover art extracted from local files (not just cached `coverUrl`)
+  - Added per-track extraction cache with file-modification invalidation so updated embedded art is reflected in Library
+  - Extraction is now on-demand for edited tracks only (not full-library reload)
+  - Returning from Track Metadata now refreshes cover cache only for the affected track
+  - Cover refresh is now skipped when file modification time is unchanged, removing unnecessary flash when simply opening/closing metadata screen
+- Fixed repeated cover preview extraction in Track Metadata screen (`track_cover_preview_*`) causing visible flash when reopening
+  - Added in-memory preview cache keyed by file path so reopening metadata reuses existing preview without re-extract
+  - Cache validation uses file modification time for filesystem paths; SAF paths are refreshed only after successful edit actions
+  - Queue/Library now also compares SAF file last-modified (`getSafFileModTimes`) before refreshing embedded-cover cache
+  - Preview cache key is now stable per track item (not volatile temp SAF path), eliminating false cache misses on SAF-backed files
+  - Track Metadata no longer auto-extracts cover preview on every screen open; extraction now runs only after actual edit/re-enrich changes (or when explicitly forced)
+- Track metadata edits/re-enrich now sync updated tags back into `downloadHistoryProvider` + SQLite history rows
+  - Non-Library screens that read download history (Home/album/history views) now reflect updated title/artist/album/tags without manual rescan
+  - Track Metadata back-navigation now returns an explicit update result after successful edits/re-enrich, enabling History-tab cover refresh fallback when SAF timestamps are unreliable
+
+### Performance
+
+- Configured Flutter image cache limits (240 entries / 60 MiB) and added `ResizeImage` wrappers for cover art precaching across all screens, reducing peak memory usage on cover-heavy pages
+- Added LRU eviction to Deezer cache with configurable max entries per cache type (search/album/artist/ISRC) and periodic expired-entry cleanup to prevent unbounded memory growth in long sessions
+- Download progress notifications are now normalized (2-decimal progress, 1-decimal speed, 0.1 MiB byte steps) and deduplicated by track/artist/percent/queue-count, reducing notification overhead during batch downloads
+- Each queue item now uses a dedicated `ConsumerWidget` with per-item `.select()` instead of rebuilding the entire list on any item change; items are wrapped in `RepaintBoundary` for paint isolation
+- Queue/Library search indexes are now built on-demand per item instead of upfront for all items, with bounded LRU caches (max 4000 entries)
+- `copyWith` now preserves derived lookup indexes (ISRC map, track key set) when items list is unchanged, avoiding O(n) rebuild on every scan progress update
+- Scan progress polling now compares values before calling `setState`, skipping unnecessary widget rebuilds when nothing changed
+- Added in-flight flag to download progress and library scan polling to prevent concurrent timer callbacks from overlapping
+- New `DownloadedEmbeddedCoverResolver` service replaces per-screen cover extraction logic with a shared bounded cache (160 entries), mod-time validation, and throttled refresh checks
+- Multiple embedded cover change callbacks are now coalesced into a single frame via `addPostFrameCallback`, preventing redundant rebuilds
+- Downloaded album screen now caches filtered/sorted track lists and reuses them when the source data reference is unchanged
+- Home tab recent downloads now use single-pass aggregation instead of building full per-album lists, and store only IDs instead of full item objects for the clear-all action
+- Removed duplicate `_downloadedSpotifyIds` Set and `_isrcSet` (both now use existing map lookups), removed unused `_isTyping` state in home tab
+- Track cache pre-warming is now capped at 80 tracks per request to avoid excessive backend calls on large playlists
+- About page contributor avatars now use `memCacheWidth`/`memCacheHeight` to decode at display size instead of full resolution
+- Orphaned download cleanup now checks file existence in parallel (chunk 16) instead of sequentially
+- Local library `findByTrackAndArtist` now uses O(1) map lookup (`_byTrackKey`) instead of O(n) linear scan
+- Local library database load and SharedPreferences fetch now run in parallel
+- Legacy mod-time backfill now uses chunked parallel `File.stat` (chunk 24) with per-chunk cancel check
+- Downloaded album screen now caches disc grouping, sorted disc numbers, common quality, and embedded cover path with reference-identity invalidation
+- Local album screen common quality is now computed once during cache rebuild instead of per-build
+- Batch delete in album screens now uses O(1) map lookup (`tracksById`) instead of `.where().firstOrNull`
+- Cache management page now fires all async init calls in parallel and uses chunked async directory deletion (chunk 24)
+- Cover resolver preview file existence check is now throttled (2.2s interval) to reduce synchronous I/O in build path
+- History and library database DELETE operations are now chunked (500 per batch) to stay within SQLite variable limits
+- Library database `cleanupMissingFiles` now checks file existence in parallel (chunk 16) and deletes in batched SQL
+
+### Security
+
+- All logs (Go and Dart) now automatically redact Bearer tokens, access/refresh tokens, client secrets, API keys, and passwords using regex-based sanitization before storage
+- Extension auth URLs are now validated for HTTPS-only, no embedded credentials, and no private/local network targets before opening
+- Auth URLs in logs are summarized to scheme+host+path only (query params stripped) to prevent token leakage; token exchange error bodies are truncated and sanitized
+- Extension HTTP requests now block URLs with embedded credentials (`user:pass@host`)
+- Extension storage files changed from `0644` to `0600` (owner-only read/write)
+- All SAF relative directory paths are now sanitized per-segment with `.`/`..` filtering; all user-provided file names pass through `sanitizeFilename()` before use
+- Extension ID is sanitized before building download destination path
+- Log export device info now shows Build ID and Security Patch level instead of masked Device ID
+
+### Technical
+
+- Centralized request serialization in `PlatformBridge` via shared invoke helper and unified payload model
+- Go strategy router normalizes incoming service casing before dispatch
+- Extension runtime: `customSearch` now passes query/options via VM globals instead of string interpolation, preventing parser edge cases on certain devices
+- Extension runtime: JS panic handler now logs full stack trace for easier debugging
+- `DownloadQueueLookup` expanded with `byItemId` map and `itemIds` list for O(1) queue item access from UI
+- Non-error/non-fatal log entries are now skipped entirely (not just hidden) when detailed logging is disabled, reducing buffer growth and Go log polling overhead
+
+### Removed
+
+- Buy Me a Coffee references removed from donate page, FUNDING.yml, README, and all localization files (account suspended)
+
+---
+
+## [3.6.0] - 2026-02-09
+
+### Highlights
+
+- **YouTube Provider (Lossy)**: New download option via Cobalt API for tracks not available on lossless services
+  - Opus 256kbps (recommended) or MP3 320kbps quality options
+  - Full metadata embedding: cover art, title, artist, album, track/disc number, year, ISRC
+  - Lyrics fetching from lrclib.net with embed and external .lrc support
+  - Works as fallback when Tidal/Qobuz/Amazon downloads fail
+- **Edit Metadata**: Edit embedded metadata directly from the Track Metadata screen (FLAC, MP3, Opus)
+  - Editable fields: Title, Artist, Album, Album Artist, Date, Track#, Disc#, Genre, ISRC
+  - Advanced fields: Label, Copyright, Composer, Comment
+  - FLAC: native Go writer, MP3/Opus: FFmpeg-based writer
+  - UI refreshes in-place after save without needing to re-open the screen
+  - iOS and Android support
+
+### Added
+
+- Save Cover Art: download high-quality album art as standalone .jpg from track metadata screen
+- Save Lyrics (.lrc): fetch and save lyrics as standalone .lrc file without downloading the song
+- Re-enrich Metadata: re-embed metadata, cover art, and lyrics into existing audio files without re-downloading (FLAC native, MP3/Opus via FFmpeg)
+- Re-enrich now supports local library items: searches Spotify/Deezer by track name + artist to fetch complete metadata from the internet, then embeds cover art, lyrics, genre, label, and all tags into the file
+- YouTube download provider using Cobalt API with SongLink/Odesli integration for Spotify/Deezer ID → YouTube URL conversion
+- SpotubeDL as fallback Cobalt proxy when primary API fails
+- YouTube video ID detection for YT Music extension compatibility
+- Parallel cover art and lyrics fetching during YouTube download
+- Queue progress now shows "X.X MB" instead of "0%" for streaming downloads where total size is unknown (Cobalt tunnel mode)
+- Full metadata pipeline for YouTube downloads: cover art, lyrics, title, artist, album, track#, disc#, year, ISRC
+
+### Changed
+
+- Removed Tidal HIGH (lossy AAC) quality option - use YouTube provider for lossy downloads instead
+- Simplified download service picker by removing dead lossy format code
+- Removed Amazon from download settings UI (now only used as automatic fallback)
+- Cleaned up dead disabled-chip code in download service selector
+
+### Fixed
+
+- Fixed `error.api.youtube.login` by using YouTube Music URLs instead of regular YouTube URLs for Cobalt requests
+- Fixed SongLink to prioritize `youtubeMusic` platform URL over `youtube` for Cobalt compatibility
+- Fixed YouTube metadata not being overwritten by setting `DisableMetadata: true` in Cobalt requests
+- Fixed ISRC validation in metadata enrichment flow - invalid ISRCs no longer trigger failed Deezer lookups
+- Fixed YouTube metadata enrichment to work like other providers (SongLink Deezer ID extraction, proper metadata embedding)
+- Go metadata parsers now read Composer, Comment, Label, Copyright from FLAC, MP3 (ID3v2.2/v2.3/v2.4), and Opus/OGG files
+- Added proper COMM frame parser for ID3v2 (handles language code + description prefix correctly)
+- Fixed Re-enrich Metadata failing on SAF storage files (`content://` URIs) - Kotlin now copies SAF file to temp, Go processes temp file, then writes back for FLAC or returns temp path for FFmpeg (MP3/Opus)
+- Fixed Save Cover Art and Save Lyrics crashing on SAF-stored download history items - now saves to temp then writes to SAF tree via `createSafFileFromPath`
+- Fixed `_getFileDirectory()` crash when called with `content://` URI by adding SAF guard
+- Fixed `readAudioMetadata` Kotlin handler not handling SAF URIs - now copies to temp for reading
+- Added metadata summary log in Re-enrich flow showing all fields before embedding (title, artist, album, track#, disc#, date, ISRC, genre, label)
+
+---
+
+## [3.5.3] - 2026-02-09
+
+### Added
+
+- CSV import flow now includes a new option: **Skip already downloaded songs** before enqueueing tracks
+- Added regression test suite for cross-script matching behavior in Go backend (`go_backend/matching_test.go`)
+
+### Changed
+
+- CSV import confirmation dialog now supports filtering out tracks already present in download history (matched by Spotify ID and ISRC)
+- CSV import enqueue feedback now reports added/skipped counts when duplicate downloads are skipped
+- Home search now prioritizes **Recent Access** when search field is focused with empty input, even if old search results still exist in memory
+- Search filter/result sections are now hidden while Recent Access mode is active to avoid stale-result overlap
+- Recent Access now shows a localized empty-state message when no recent items are available
+- Normalized collapsing AppBar top inset across iOS/Android so header height/animation stays visually consistent on Apple devices
+- Storage & Cache UX improved: `Clear all cache` now preserves web/runtime cache by default (optional), with explicit warnings/actions for runtime cache resets
+- Local library settings now include a display count for tracks excluded because they already exist in download history
+- Responsive layout tuning applied across key screens to reduce hardcoded-height overflow issues on smaller devices
+
+### Fixed
+
+- Fixed false-positive cross-script matching in Qobuz/Tidal where unrelated titles/artists in different scripts could be incorrectly accepted
+- Cross-script title/artist matching now requires transliteration-aware normalization and strict similarity checks instead of auto-accepting script differences
+- Qobuz metadata fallback no longer scans all results when zero title matches are found; title verification is now required
+- Qobuz metadata final validation now rejects results when title does not match expected track name
+- Fixed Home search regression where Recent Access panel could disappear after previous searches
+- Fixed Local Library card/layout crash caused by `Flex` usage under unbounded height constraints
+- Hardened FFmpeg metadata embedding temp-file naming to prevent rare collisions during parallel downloads/fallback flows (Qobuz → Tidal) that could cause missing embedded metadata
+- Fixed SAF external lyrics naming where some providers saved `.lrc` files as `.lrc.txt`; LRC export now uses neutral MIME to preserve `.lrc` extension
+
+## [3.5.2] - 2026-02-08
+
+### Performance
+
+- Home tab search result sections are now virtualized with `SliverList` (lazy item build) instead of eager `Column` rendering, reducing frame drops on large result sets
+- Home tab now narrows Riverpod subscriptions using field-level `select(...)` for search/provider state to reduce unnecessary full-tab rebuilds
+- Search provider dropdown now watches only required fields (`searchProvider`, `metadataSource`, `extensions`) instead of full provider states
+- Track row rendering in Home search now receives precomputed thumbnail sizing/local-library flags from parent to avoid repeated per-item provider watches
+- Removed thumbnail `debugPrint` calls inside track row `build()` to reduce runtime overhead during scrolling/rebuilds
+- Queue tab root subscription no longer watches full queue item list; it now watches only queue presence (`items.isNotEmpty`) to avoid full Library UI rebuilds on every progress tick
+- Queue download header/list rendering has been isolated into dedicated `Consumer` slivers; header now watches only queue length (`items.length`) while item list watches queue item updates
+- Queue filter/sort computations are now centralized and memoized per filter mode within a build pass (`all`/`albums`/`singles`), reducing repeated list transforms for chip counts and page content
+- Selection bottom bar content is now computed only when selection mode is active, removing hidden-state heavy list preparation
+- File existence checks in queue/library rows now use per-path `ValueNotifier` + `ValueListenableBuilder` updates instead of triggering global `setState`, reducing unnecessary whole-tab repaints
+
+### Changed
+
+- Replaced date range filter with sorting options in Library tab: Latest, Oldest, A-Z, Z-A
+- Sorting applies to all views: unified items, downloaded albums, and local library albums
+- Local library items now use file modification time (`fileModTime`) for sorting instead of scan time, providing more accurate chronological ordering
+- Removed redundant manual "Export Failed Downloads" button from Library UI (auto-export setting in Settings is sufficient)
+- Library filters (quality, format, source) now correctly apply to album tabs and update tab chip counts (All/Albums/Singles)
+
+### Fixed
+
+- Fixed local library scan crashing on Samsung One UI devices due to MediaStore URI mismatch in SAF tree traversal
+- Added MediaStore URI fallback in SAF file reader: when SAF permission is denied for Samsung-returned MediaStore URIs, automatically retries using READ_MEDIA_AUDIO permission
+- Hardened SAF scan with per-directory and per-file error handling: scan now skips problematic files instead of aborting entirely
+- Added visited directory tracking to prevent infinite loops from circular SAF references
+- Fixed metadata enrichment cascading failure after one queued download fails: metadata APIs (Deezer, SongLink, Spotify) now use isolated `metadataTransport` so failed download connections cannot poison metadata requests
+- Added immediate connection cleanup on every download failure path (error response and exception), not only periodic cleanup every N downloads
+- Fixed incremental SAF scan edge case where `lastModified()` failure could misclassify existing files as removed (`removedUris`)
+- Fixed tracks marked "In Library" still showing active download button - download button now shows as completed (checkmark) for local library tracks across all screens (album, playlist, artist, home/search)
+- Fixed FFmpeg M4A-to-FLAC conversion erroneously triggered on already-existing FLAC files when re-downloading duplicates via Tidal
+- Fixed SAF download creating empty artist/album folders when re-downloading duplicate tracks; directory is now only created after confirming the file does not already exist
+
+## [3.5.1] - 2026-02-08
+
+### Performance
+
+- Removed PaletteService (palette_generator) from all screens for faster navigation and reduced memory usage
+- Album, Playlist, Downloaded Album, Local Album, and Track Metadata screens now use blurred cover art as header background instead of dominant color extraction
+- Removed `palette_generator` dependency
+- App startup now renders immediately (`runApp`) while service initialization runs asynchronously in eager init
+- Main shell provider subscriptions now use field-level `select(...)` to reduce unnecessary rebuilds
+- Settings persistence now uses single-flight + queued save coalescing to avoid redundant disk writes
+- Progress polling cadence adjusted to 800ms for download queue, local library scan progress, and Go log polling
+- Android foreground download service progress updates are throttled (change-based updates + 5s heartbeat)
+- SAF history repair is now batched (`20` items per batch) and capped per launch (`60`) to reduce startup I/O spikes
+- Incremental library scan now builds final item list in-memory instead of reloading from database
+- Local cover images in queue/library use direct `Image.file` with `errorBuilder` instead of `FutureBuilder` existence check
+- CSV parser `_parseLine` rewritten: correct escaped-quote handling, no quote characters in output
+- Removed unused legacy screen files (`home_screen.dart`, `queue_screen.dart`, `settings_screen.dart`, `settings_tab.dart`)
+- Incremental local library scan now merges delta results in-memory and sorts once, avoiding full-state reload churn
+- Queue local cover rendering now uses direct `Image.file` + `errorBuilder` (removed repeated async file-exists checks)
+
+### Added
+
+- Auto-cleanup orphaned downloads on history load (files that no longer exist are automatically removed from history)
+
+### Changed
+
+- Removed legacy screen files that were no longer used after the tab/part refactor:
+  - `lib/screens/home_screen.dart`
+  - `lib/screens/queue_screen.dart`
+  - `lib/screens/settings_screen.dart`
+  - `lib/screens/settings_tab.dart`
+- Concurrent download limit increased from `3` to `5` (settings clamp + Options UI chips now support `1..5`)
+- Download queue now uses a single parallel scheduler path; `1` concurrency is handled as parallel-with-limit-1 (no separate sequential engine)
+- Download queue now listens to settings updates in real-time so concurrency/output settings stay in sync while queue is active
+
+### Fixed
+
+- CSV parser now correctly handles escaped quotes (`""`) inside quoted fields during import
+- Fixed dynamic concurrency update during active downloads: changing limit (e.g. `1 -> 3`) now schedules additional queued items without waiting current active item to finish
+- Queue scheduler now re-checks capacity/queued items on short intervals to avoid blocking on long-running single active download
+
+### Dependencies
+
+#### Flutter
+- `flutter_local_notifications` 19.x → 20.0.0 (breaking: all positional params converted to named params)
+- `connectivity_plus` 6.x → 7.0.0
+- `flutter_secure_storage` 9.x → 10.0.0
+- Removed `palette_generator` dependency
+
+#### Go
+- `go-flac/go-flac` v1.0.0 → v2.0.4
+- `go-flac/flacvorbis` v0.2.0 → v2.0.2
+- `go-flac/flacpicture` v0.3.0 → v2.0.2
+- Go toolchain 1.24 → 1.25.7
+
+#### Android
+- Android Gradle Plugin 8.x → 9.0.0
+- Kotlin 2.1.x → 2.3.10
+- `desugar_jdk_libs` → 2.1.5
+- `kotlinx-coroutines-android` → 1.10.2
+- `lifecycle-runtime-ktx` → 2.10.0
+- `activity-ktx` → 1.12.3
+
+#### CI/CD
+- `actions/cache` v4 → v5
+- `actions/checkout` v4 → v6
+- `actions/setup-go` v5 → v6
+- `actions/setup-java` v4 → v5
+- `softprops/action-gh-release` v1 → v2
+- GitHub artifact actions updated
+
+---
+
+## [3.5.0] - 2026-02-07
+
+### Highlights
+
+- **SAF Storage (Android 10+)**: Proper Storage Access Framework support for download destination (content URIs)
+  - Select download folder via SAF tree picker
+  - Downloads now write to SAF file descriptors (`/proc/self/fd/*`) instead of raw filesystem paths
+  - Works around Android 10+ scoped storage permission errors
+- **Modern Onboarding Experience**: Completely redesigned Setup and Tutorial screens
+
+### Added
+
+- Home feed disk caching via SharedPreferences for instant restore on app startup
+- SAF display path resolver in native Android layer (converts tree URIs to readable paths)
+- New settings fields for storage mode + SAF tree URI
+- SAF platform bridge methods: pick tree, stat/exists/delete, open content URI, copy to temp, write back to SAF
+- SAF library scan mode (DocumentFile traversal + metadata read)
+- Incremental library scanning for filesystem and SAF paths (only scans new/modified files and detects removed files)
+- Force Full Scan action in Library Settings to rescan all files on demand
+- Downloaded files are now excluded from Local Library scan results to prevent duplicate entries
+- Legacy library rows now support `file_mod_time` backfill before incremental scans (faster follow-up scans after upgrade)
+- Library UI toggle to show SAF-repaired history items
+- Scan cancelled banner + retry action for library scans
+- Android DocumentFile dependency for SAF operations
+- Post-processing API v2 (SAF-aware, ready to replace v1)
+- Donate page in Settings with Ko-fi and Buy Me a Coffee links
+- Per-App Language support on Android 13+ (locale_config.xml)
+- Interactive tutorial with working search bar simulation and clickable download buttons
+- Tutorial completion state is persisted after onboarding
+- Visual feedback animations for page transitions, entrance effects, and feature lists
+- New dedicated welcome step in setup wizard with improved branding
+
+### Changed
+
+- Download pipeline supports `output_path` + `output_ext` for Go backend
+- Tidal/Qobuz/Amazon/Extension downloads use SAF-aware output when enabled
+- Post-processing hooks run for SAF content URIs (via temp file bridge)
+- File operations in Library/Queue/Track screens now SAF-aware (`open`, `exists`, `delete`, `stat`)
+- Local Library scan defaults to incremental mode; full rescan is available via Force Full Scan
+- Local library database upgraded to schema v3 with `file_mod_time` tracking for incremental scan cache
+- Platform channels expanded with incremental scan APIs (`scanLibraryFolderIncremental`) on Android and iOS
+- Android platform channel adds `getSafFileModTimes` for SAF legacy cache backfill
+- Android build tooling upgraded to Gradle 9.3.1 (wrapper)
+- Android build path validated with Java 25 (Gradle/Kotlin/assemble debug)
+- SAF tree picker flow in `MainActivity` migrated to Activity Result API (`registerForActivityResult`)
+- `MainActivity` host migrated to `FlutterFragmentActivity` for SAF picker compatibility
+- Legacy `startActivityForResult` / `onActivityResult` SAF picker path removed
+- Setup screen UI polish: smaller logo, thin outline borders on text fields
+- Removed support section from About page (moved to Donate page)
+- Qobuz squid.wtf region fallback for blocked regions
+- Setup screen converted to PageView flow with animated progress bar and modern card layouts
+- Tutorial screen aligned with Setup Screen design, updated typography and softened UI shapes
+- Larger, more accessible navigation buttons for onboarding flow
+- Reduced visual noise by removing unnecessary glow effects
+
+### Fixed
+
+- Android 10+ `permission denied` when writing to `/storage/emulated/0` (now handled via SAF)
+- SAF history repair: auto-resolve missing content URIs using tree + filename
+- SAF download fallback: retry in app-private storage when SAF write fails
+- Tidal DASH manifest writing when output path is a file descriptor (no invalid `.m4a` path)
+- External LRC output in SAF mode
+- Restored old-device renderer fallback while using `FlutterFragmentActivity` by injecting shell args from a custom `FlutterFragment` (`--enable-impeller=false` on problematic devices)
+- Preserved Flutter fragment creation behavior (cached engine, engine group, new engine) while adding Impeller fallback support
+- SAF tree picker result now consistently returns `tree_uri` payload with persisted URI permission handling
+- SAF share file now copies to temp before sharing (fixes share from SAF content URI)
+- Home feed not updating after installing extension with homeFeed capability (no longer requires app restart)
+- Library scan hero card showing 0 tracks during scan (now shows scanned file count in real-time)
+- Library folder picker no longer requires MANAGE_EXTERNAL_STORAGE on Android 10+ (uses SAF tree picker)
+- One-time SAF migration prompt for users updating from pre-SAF versions
+- Fixed `fileModTime` propagation across Go/Android/Dart so incremental scan cache is stored and reused correctly
+- Fixed SAF incremental scan key mismatch (`lastModified` vs `fileModTime`) and normalized result fields (`skippedCount`, `totalFiles`)
+- Fixed incremental scan progress when all files are skipped (`scanned_files` now reaches total files)
+- Removed duplicate `"removeExtension"` branch in Android method channel handler (eliminates Kotlin duplicate-branch warning)
+
+---
+
+## [3.4.2] - 2026-02-04
+
+### Improved
+
+- **Mobile Network Reliability**: All providers (Qobuz, Tidal, Amazon, Deezer) now have retry logic with exponential backoff
+  - Increased API timeouts: 15s → 25s (Deezer, Qobuz, Tidal), 30s (Amazon)
+  - Up to 3 retry attempts per API call (500ms → 1s → 2s backoff)
+  - Retryable: timeout, connection reset/refused, EOF, HTTP 5xx, HTTP 429
+- **SongLink ID Extraction**: Extract QobuzID/TidalID directly from SongLink URLs
+  - New fields in `TrackAvailability`: `QobuzID`, `TidalID`
+  - Qobuz/Tidal now use direct Track ID from SongLink instead of re-parsing URLs
+- **Qobuz Download Flow**: New Strategy 3 - get QobuzID from SongLink before ISRC search
+  - Cache hit now uses `GetTrackByID()` directly instead of searching again
+  - Pre-warm cache tries SongLink first before direct ISRC search
+- **Tidal Download Flow**: Use `availability.TidalID` directly from SongLink struct
+
+---
+
+## [3.4.1] - 2026-02-04
+
+### Fixed
+
+- Metadata Priority order now persists after app restart
+- Download Provider Priority order now persists after app restart
+
+---
+
+## [3.4.0] - 2026-02-03
+
+### Highlights
+
+- **Local Library Scanning** ([#117](https://github.com/zarzet/SpotiFLAC-Mobile/issues/117)): Scan existing music collection to detect duplicates (FLAC, M4A, MP3, Opus, OGG)
+- **Duplicate Detection** ([#117](https://github.com/zarzet/SpotiFLAC-Mobile/issues/117)): "In Library" badge on tracks matching by ISRC or track name + artist
+- **Unified Library Tab**: History renamed to Library, shows Downloaded + Local Library tracks with source badges
+
+### Added
+
+- Local Album Screen with cover art, disc grouping, and selection mode
+- Albums tab shows local library albums with folder icon badge
+- Singles filter includes local library singles
+- Advanced library filters: Source, Quality, Format, Date
+- Cover art extraction from embedded tags (FLAC, MP3, Opus/Ogg)
+- "Already in Library" notification when downloading existing tracks
+- Spotify secrets now stored in secure storage (`flutter_secure_storage`)
+- **Multi-Service Link Support**: Share links from Deezer, Tidal, and YouTube Music (in addition to Spotify)
+  - Deezer: Full support for track, album, playlist, artist links
+  - Tidal: Track links converted via SongLink to Spotify/Deezer for metadata
+  - YouTube Music: Handled via ytmusic extension URL handler
+- Local library tracks now open metadata screen on tap
+
+### Changed
+
+- Extension HTTP sandbox enforces HTTPS and blocks private IPs
+- Extension file sandbox validates paths with boundary-safe checks
+
+### Fixed
+
+- Search filter bar now only appears after results load, not during loading
+- MP3/Ogg metadata parsing (ID3v2 extended headers, Ogg packet reassembly)
+- Library scan metadata (ISRC, disc number, release date)
+- Cover cache robustness (size + mtime cache key)
+- Local library selection and delete in list/grid views
+- Albums/Singles count includes local library items
+
+---
+
+## [3.3.6] - 2026-02-02
+
+### Added
+
+- **WiFi-Only Download Mode**: Pause downloads on mobile data, auto-resume on WiFi (Settings > Download > Download Network)
+- Added `connectivity_plus: ^6.0.3` dependency
+
+---
+
+## [3.3.5] - 2026-02-01
+
+Same as 3.3.1 but fixes crash issues caused by FFmpeg.
+
+### Added
+
+- **Export Failed Downloads**: Export failed downloads to TXT file for easy lookup on other platforms
+- **Auto-Export Setting**: Option to automatically export failed downloads when queue finishes
+
+### Fixed
+
+- **FFmpeg Crash**: Fixed crash issues during M4A to MP3/Opus conversion
+- **Service Selection Ignored**: Fixed bug where selecting Qobuz/Amazon from service picker was ignored and always used Tidal instead
+- **iOS iCloud Drive Permission Error**: Block iCloud Drive folder selection on iOS (Go backend cannot access iCloud due to sandboxing)
+
+### Changed
+
+- **Amazon Fallback Only**: Amazon Music is now grayed out in service picker and can only be used as fallback provider
+
+---
+
+## [3.3.1] - 2026-02-01
 
 ### Added
 
@@ -9,18 +569,19 @@
 - **Lossy Bitrate Options**: MP3 (320/256/192/128kbps), Opus (128/96/64kbps)
 - **Search Filters**: Filter results by type (Tracks, Artists, Albums, Playlists)
 - **Album/Playlist Search**: Deezer search now includes albums and playlists
-- **New Languages**: Turkish (Kaan, BedirhanGltkn), Japanese (Re*Index.(ot_inc))
+- **New Languages**: Turkish (Kaan, BedirhanGltkn), Japanese (Re\*Index.(ot_inc))
 - **Optional All Files Access**: Android 13+ no longer requires full storage access; enable in Settings if needed
 - **Improved VPN Compatibility**: Better HTTP/2 support for users behind VPN or restricted networks
 
 ### Changed
 
-- **Amazon Download API**: Switched to AfkarXYZ API ([#108](https://github.com/zarzet/SpotiFLAC-Mobile/issues/108))
-- **Qobuz Download API**: Added Jumo API as fallback ([#108](https://github.com/zarzet/SpotiFLAC-Mobile/issues/108))
+- **Amazon Download API**: Switched to AfkarXYZ API
+- **Qobuz Download API**: Added Jumo API as fallback
 - **Search Results**: Reduced artist limit from 5 to 2
 
 ### Fixed
 
+- **MP3 Download Error 403**: Fixed 403 Forbidden error when downloading MP3 files ([#108](https://github.com/zarzet/SpotiFLAC-Mobile/issues/108))
 - **Opus Cover Art**: Implemented METADATA_BLOCK_PICTURE for proper cover embedding
 - **Deezer Pagination**: Fixed >25 tracks only showing first 25 ([#112](https://github.com/zarzet/SpotiFLAC-Mobile/issues/112))
 - **Duplicate Embed Lyrics Setting**: Removed from Options page ([#110](https://github.com/zarzet/SpotiFLAC-Mobile/issues/110))
@@ -109,31 +670,26 @@
   - Perfect for players like Samsung Music that prefer external .lrc files
   - LRC files include metadata headers (title, artist, by:SpotiFLAC-Mobile)
   - Works with all download services (Tidal, Qobuz, Amazon)
-
 - **CSV Import Quality Selection**: Choose audio quality when importing CSV playlists
   - Quality picker now appears before adding CSV tracks to download queue
   - Select between FLAC qualities (Lossless, Hi-Res, Hi-Res Max) or MP3
   - Respects "Ask quality before download" setting - uses default quality if disabled
-
   - **Persistent Cover Image Cache**: Album/track cover images now cached to persistent storage instead of temporary directory
   - Cover images no longer disappear when app is closed or device restarts
   - Cache stored in `app_flutter/cover_cache/` directory (not cleared by system)
   - Maximum 1000 images cached for up to 365 days
   - Covers are cached when displayed in History, Home, Album, Artist, or any other screen
   - New `CoverCacheManager` service with `clearCache()` and `getStats()` methods for future cache management
-
 - **Extended Metadata from Deezer Enrichment**: Track downloads now include label, copyright, and genre metadata from Deezer
   - New fields in `ExtTrackMetadata`: `label`, `copyright`, `genre`
   - Metadata fetched during `enrichTrack()` via Deezer album API
   - Embedded as FLAC Vorbis comments: `GENRE`, `ORGANIZATION` (label), `COPYRIGHT`
   - Works for both extension downloads and built-in provider downloads (Tidal, Qobuz, Amazon)
-
 - **Track Metadata Screen Extended Info**: Genre, label, and copyright now displayed in track metadata screen
   - Added `genre`, `label`, `copyright` fields to `DownloadHistoryItem` model
   - Metadata is stored in download history and persists across app restarts
   - New localization strings: `trackGenre`, `trackLabel`, `trackCopyright`
-
-- **`utils.randomUserAgent()` for Extensions**: New utility function for extensions to get random browser User-Agent strings
+- `**utils.randomUserAgent()` for Extensions\*\*: New utility function for extensions to get random browser User-Agent strings
   - Returns modern Chrome User-Agent format: `Chrome/{120-145}.0.{6000-7499}.{100-299}` with `Windows NT 10.0`
   - Useful for extensions that need to rotate User-Agents to avoid detection
 
@@ -142,7 +698,6 @@
 - **Portuguese Language Bug**: Fixed locale parsing for languages with country codes (e.g., pt_PT, es_ES)
   - App now correctly loads Portuguese and Spanish translations
   - Updated Portuguese label to "Português (Brasil)"
-
 - **VM Race Condition Panic**: Fixed `panic during execution: runtime error: index out of range [-2]` crash when switching search providers
   - Root cause: Goja VM was being accessed concurrently by multiple goroutines without synchronization
   - Added `VMMu sync.Mutex` to `LoadedExtension` struct
@@ -151,16 +706,13 @@
     - `EnrichTrack`, `CheckAvailability`, `GetDownloadURL`, `Download`
     - `CustomSearch`, `HandleURL`, `MatchTrack`, `PostProcess`
   - Prevents race conditions when rapidly switching between extension search providers
-
 - **Tidal Release Date Fallback**: Fixed missing release date in FLAC metadata when downloading from Tidal
   - Now uses Tidal API's release date when `req.ReleaseDate` is empty
   - Ensures release date is always embedded in downloaded files
-
 - **Extended Metadata for M4A→FLAC Conversion**: Fixed genre, label, and copyright not being embedded when converting Amazon M4A to FLAC
   - Flutter now extracts extended metadata from Go backend response
   - Passes `genre`, `label`, `copyright` parameters to `_embedMetadataAndCover()`
   - Tags correctly embedded during FFmpeg conversion
-
 - **Extended Metadata for MP3 Conversion**: Genre, label, and copyright now embedded in MP3 files when converting from FLAC
   - Added `genre`, `label`, `copyright` parameters to `_embedMetadataToMp3()`
   - Tags embedded as ID3v2: `GENRE`, `ORGANIZATION` (label), `COPYRIGHT`
@@ -221,7 +773,6 @@
   - `go_backend/httputil.go`: Updated `getRandomUserAgent()` to use modern Chrome versions
   - `go_backend/tidal.go`: Added release date fallback logic
   - `go_backend/exports.go`: Added `Genre`, `Label`, `Copyright` fields to `DownloadResponse`
-
 - **Flutter Changes**:
   - `lib/services/cover_cache_manager.dart`: New persistent cache manager for cover images (365 days, 1000 images max)
   - `lib/widgets/cached_cover_image.dart`: Wrapper widget for CachedNetworkImage with persistent cache
@@ -246,7 +797,6 @@
   - Spanish: Credits 125 ([@credits125](https://crowdin.com/profile/credits125))
   - Portuguese: Pedro Marcondes ([@justapedro](https://crowdin.com/profile/justapedro))
   - Russian: Владислав ([@odinokiy_kot](https://crowdin.com/profile/odinokiy_kot))
-
 - **Quick Search Provider Switcher** ([#76](https://github.com/zarzet/SpotiFLAC-Mobile/issues/76)): Dropdown menu in search bar for instant provider switching
   - Tap the search icon to reveal a dropdown menu with all available search providers
   - Shows default provider (Deezer based on metadata source setting) at the top
@@ -256,56 +806,46 @@
   - Search hint text updates immediately when switching providers
   - Re-triggers search automatically if there's existing text in the search bar
   - Eliminates need to navigate to Settings > Extensions > Search Provider
-
 - **Extension Button Setting Type** ([#74](https://github.com/zarzet/SpotiFLAC-Mobile/issues/74)): New setting type for extension actions
   - Extensions can define `button` type in manifest settings
   - Triggers JavaScript function when tapped (e.g., start OAuth flow)
   - Useful for authentication, manual sync, or any custom action
-
 - **Genre & Label Metadata** ([#75](https://github.com/zarzet/SpotiFLAC-Mobile/issues/75)): Downloaded tracks now include genre and record label information
   - Fetches genre and label from Deezer album API for each track
   - Embeds GENRE, ORGANIZATION (label), and COPYRIGHT tags into FLAC files
   - Works automatically when Deezer track ID is available (via ISRC matching)
   - Supports all download services (Tidal, Qobuz, Amazon) and extension downloads
-
 - **MP3 Quality Option** ([#69](https://github.com/zarzet/SpotiFLAC-Mobile/issues/69)): Optional MP3 download format with FLAC-to-MP3 conversion
   - New "Enable MP3 Option" toggle in Settings > Download > Audio Quality
   - When enabled, MP3 (320kbps) appears as a quality option alongside FLAC options
   - Available in both the quality picker dialog and default quality settings
   - Works with all services (Tidal, Qobuz, Amazon) and extensions
-
 - **MP3 Metadata Embedding**: Full metadata support for MP3 files
   - Cover art embedded using ID3v2 tags
   - Synced lyrics embedded (fetched from lrclib.net)
   - All metadata preserved: title, artist, album, album artist, track/disc number, date, ISRC
   - Automatic tag conversion from Vorbis comments (FLAC) to ID3v2 (MP3)
-
 - **Dominant Color Header**: Album, Playlist, Downloaded Album, and Track Metadata screens now feature dynamic header backgrounds
   - Extracts dominant color from cover art using `palette_generator`
   - Creates a gradient from dominant color to theme surface color
   - Smooth 500ms color transition animation
-
 - **Larger Cover Art**: Cover images on detail screens are now 50% of screen width (previously 140px fixed)
   - More prominent album artwork display
   - Larger shadow and rounded corners (20px radius)
   - Higher resolution cover caching
-
 - **Sticky Title**: Title appears in AppBar when scrolling past the info card
   - Smooth fade-in animation (200ms) when scrolling down
   - Title hidden when header is expanded (shows in info card instead)
   - AppBar uses theme color (surface) for clean, native look
   - Works on Album, Playlist, Downloaded Album, Track Metadata, and Artist screens
-
 - **Artist Name in Album Screen**: Album info card now displays artist name below album title
   - Extracted from first track's artist metadata
   - Styled with `onSurfaceVariant` color for visual hierarchy
-
 - **Disc Separation for Multi-Disc Albums** ([#70](https://github.com/zarzet/SpotiFLAC-Mobile/issues/70)): Downloaded albums with multiple discs now display tracks grouped by disc
   - Visual disc separator header showing "Disc 1", "Disc 2", etc.
   - Tracks sorted by disc number first, then by track number
   - Single-disc albums display normally without separators
   - Fixes confusion when albums have duplicate track numbers across discs
-
 - **Album Grouping in Recents** ([#70](https://github.com/zarzet/SpotiFLAC-Mobile/issues/70)): Downloads now show as albums instead of individual tracks in the Recent section
   - Prevents flooding the recents list when downloading full albums
   - Groups tracks by album name and artist
@@ -318,7 +858,6 @@
   - MP3 files now saved in the same folder as FLAC (no separate MP3 subfolder)
   - Original FLAC file automatically deleted after successful conversion
   - New `embedMetadataToMp3()` method for MP3-specific tag embedding
-
 - **Sticky Header Theme Integration**: AppBar background uses `colorScheme.surface` instead of dominant color when collapsed
   - Dark theme: Black background with white text
   - Light theme: White background with black text
@@ -330,12 +869,10 @@
   - MP3 files now show "320kbps" instead of FLAC's bit depth/sample rate
   - History no longer stores FLAC audio specs for converted MP3 files
   - Both File Info badges and metadata grid show correct MP3 quality
-
 - **Empty Catch Blocks**: Fixed analyzer warnings for empty catch blocks
   - `download_queue_provider.dart`: Added comments explaining why polling errors are silently ignored
   - `track_provider.dart`: Added comments explaining why availability check errors are silently ignored
   - `ffmpeg_service.dart`: Added proper error logging for temp file cleanup failures
-
 - **Russian Plural Forms**: Fixed ICU syntax warnings in Russian localization
   - Removed redundant `=1` clauses that were overriding `one` plural category
   - Affected 10 plural strings including track counts and delete confirmations
@@ -355,24 +892,20 @@
   - Thread-safe cache with automatic expiration
   - Cache key based on artist, track, and duration
   - Log indicator shows "(cached)" when lyrics are served from cache
-
 - **Lyrics Duration Matching**: Improved lyrics accuracy with duration-based matching
   - Compares track duration with lrclib.net results
   - 10-second tolerance to handle version differences (radio edit, remaster, etc.)
   - Prioritizes synced lyrics over plain text when duration matches
   - Falls back gracefully if no duration match found
-
 - **Deezer Cover Art Upgrade**: Cover art from Deezer CDN now automatically upgraded to maximum quality
   - Detects Deezer CDN URLs (`cdn-images.dzcdn.net`)
   - Upgrades cover resolution to 1800x1800 (max available)
   - Works alongside existing cover upgrade
-
 - **Live Search for Extensions**: Search-as-you-type functionality for extension search
   - 800ms debounce delay to prevent excessive API calls
   - Minimum 3 characters required before searching
   - Concurrency control to prevent race conditions in extension runtime
   - Queues pending searches if a search is already in progress
-
 - **Russian Language Support**: Added Russian (Русский) translation - 99% complete
   - Translated via Crowdin community contributions
   - Covers all UI elements, settings, and error messages
@@ -383,12 +916,10 @@
   - Added per-directory build lock using `sync.Map` and `sync.Mutex`
   - Double-check locking pattern ensures index is built only once
   - Significantly improves performance during CSV import with many tracks
-
 - **Queue Tab Scroll Exception**: Fixed Flutter rendering exception with NestedScrollView
   - Disabled Material 3 stretch overscroll indicator that caused `_StretchController` assertion
   - Wrapped NestedScrollView with ScrollConfiguration to prevent `setState during build` errors
   - Issue was especially noticeable during rapid queue updates (CSV import)
-
 - **CSV Import**: Fixed CSV export not being parsed correctly
   - Added support for `Artist Name(s)` header (with parentheses)
   - Added support for `Track URI` header for track IDs
@@ -455,4 +986,4 @@ SpotiFLAC 3.0 introduces a powerful extension system that allows third-party int
 
 ---
 
-*For older versions, see [GitHub Releases](https://github.com/zarzet/SpotiFLAC-Mobile/releases)*
+_For older versions, see [GitHub Releases_](https://github.com/zarzet/SpotiFLAC-Mobile/releases)

README.md

@@ -1,5 +1,5 @@
-[![GitHub All Releases](https://img.shields.io/github/downloads/zarzet/SpotiFLAC-Mobile/total?style=for-the-badge&refresh=1)](https://github.com/zarzet/SpotiFLAC-Mobile/releases)
-[![VirusTotal](https://img.shields.io/badge/VirusTotal-Safe-brightgreen?style=for-the-badge&logo=virustotal)](https://www.virustotal.com/gui/file/516142f029a4f3642a899832a6f600acf07040170a98c106cd03222cf584d9a3)
+[![GitHub All Releases](https://img.shields.io/github/downloads/zarzet/SpotiFLAC-Mobile/total?style=for-the-badge)](https://github.com/zarzet/SpotiFLAC-Mobile/releases)
+[![VirusTotal](https://img.shields.io/badge/VirusTotal-Safe-brightgreen?style=for-the-badge&logo=virustotal)](https://www.virustotal.com/gui/file/40f8f1914287dea317122a837f98b0ddf7af3205adc2f84a350d767e0a6a345c)
 [![Crowdin](https://img.shields.io/badge/HELP%20TRANSLATE%20ON-CROWDIN-%2321252b?style=for-the-badge&logo=crowdin)](https://crowdin.com/project/spotiflac-mobile)
 
 <div align="center">
@@ -24,15 +24,6 @@ Download music in true lossless FLAC from Tidal, Qobuz & Amazon Music — no acc
   <img src="assets/images/4.jpg?v=2" width="200" />
 </p>
 
-## Search Source
-
-SpotiFLAC supports multiple search sources for finding music metadata:
-
-| Source | Setup |
-|--------|-------|
-| **Deezer** (Default) | No setup required |
-| **Extensions** | Install additional search providers from the Store |
-
 ## Extensions
 
 Extensions allow the community to add new music sources and features without waiting for app updates. When a streaming service API changes or a new source becomes available, extensions can be updated independently.
@@ -54,15 +45,8 @@ Download music in true lossless FLAC from Tidal, Qobuz & Amazon Music for Window
 
 ## Telegram
 
-<p align="center">
-  <a href="https://t.me/spotiflac">
-    <img src="https://img.shields.io/badge/Telegram-Channel-2CA5E0?style=for-the-badge&logo=telegram&logoColor=white" alt="Telegram Channel">
-  </a>
-
-  <a href="https://t.me/spotiflac_chat">
-    <img src="https://img.shields.io/badge/Telegram-Community-2CA5E0?style=for-the-badge&logo=telegram&logoColor=white" alt="Telegram Community">
-  </a>
-</p>
+[![Telegram Channel](https://img.shields.io/badge/CHANNEL-2CA5E0?style=for-the-badge&logo=telegram&logoColor=white)](https://t.me/spotiflac)
+[![Telegram Community](https://img.shields.io/badge/COMMUNITY-2CA5E0?style=for-the-badge&logo=telegram&logoColor=white)](https://t.me/spotiflac_chat)
 
 ## FAQ
 
@@ -87,9 +71,9 @@ A: Some countries have restricted access to certain streaming service APIs. If d
 
 ### Want to support SpotiFLAC-Mobile?
 
-_If this software is useful and brings you value, consider supporting the project by buying me a coffee. Your support helps keep development going._
+_If this software is useful and brings you value, consider supporting the project. Your support helps keep development going._
 
-[![Ko-fi](https://ko-fi.com/img/githubbutton_sm.svg)](https://ko-fi.com/zarzet) <a href="https://www.buymeacoffee.com/zarzet" target="_blank"><img src="https://cdn.buymeacoffee.com/buttons/v2/default-yellow.png" alt="Buy Me A Coffee" style="height: 40px !important;width: 150px !important;" ></a>
+[![Ko-fi](https://ko-fi.com/img/githubbutton_sm.svg)](https://ko-fi.com/zarzet)
 
 
 ## Disclaimer
@@ -108,6 +92,16 @@ You are solely responsible for:
 The software is provided "as is", without warranty of any kind. The author assumes no liability for any bans, damages, or legal issues arising from its use.
 
 
+## API Credits
+
+- **Tidal**: [hifi-api](https://github.com/binimum/hifi-api), [music.binimum.org](https://music.binimum.org), [qqdl.site](https://qqdl.site), [squid.wtf](https://squid.wtf), [spotisaver.net](https://spotisaver.net)
+- **Qobuz**: [dabmusic.xyz](https://dabmusic.xyz), [squid.wtf](https://squid.wtf), [jumo-dl](https://jumo-dl.pages.dev)
+- **Amazon**: [AfkarXYZ](https://github.com/afkarxyz)
+- **Lyrics**: [LRCLib](https://lrclib.net)
+- **YouTube Audio**: [Cobalt](https://cobalt.tools) via [qwkuns.me](https://qwkuns.me), [SpotubeDL](https://spotubedl.com)
+- **Track Linking**: [SongLink / Odesli](https://odesli.co), [IDHS](https://github.com/sjdonado/idonthavespotify)
+
+
 > [!TIP]
 >
 > **Star Us**, You will receive all release notifications from GitHub without any delay ~

android/app/build.gradle.kts

@@ -96,11 +96,13 @@ repositories {
 }
 
 dependencies {
-    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs:2.1.4")
+    coreLibraryDesugaring("com.android.tools:desugar_jdk_libs:2.1.5")
     
     // Include all AAR and JAR files from libs folder
     implementation(fileTree(mapOf("dir" to "libs", "include" to listOf("*.jar", "*.aar"))))
     
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.7.3")
-    implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.7.0")
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-android:1.10.2")
+    implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.10.0")
+    implementation("androidx.documentfile:documentfile:1.1.0")
+    implementation("androidx.activity:activity-ktx:1.12.3")
 }

android/app/proguard-rules.pro

@@ -5,6 +5,7 @@
 -keep class io.flutter.view.** { *; }
 -keep class io.flutter.** { *; }
 -keep class io.flutter.plugins.** { *; }
+-keep class io.flutter.embedding.** { *; }
 
 # Ignore missing Play Core classes (not used, but referenced by Flutter)
 -dontwarn com.google.android.play.core.splitcompat.**
@@ -14,13 +15,22 @@
 # Ignore missing javax.xml.stream (not used on Android)
 -dontwarn javax.xml.stream.**
 
-# Go backend (gobackend.aar)
+# Go backend (gobackend.aar) - CRITICAL for release builds
 -keep class gobackend.** { *; }
 -keep class go.** { *; }
+-keep interface gobackend.** { *; }
+-keepclassmembers class gobackend.** { *; }
+
+# Go mobile binding internals
+-keep class org.golang.** { *; }
+-dontwarn org.golang.**
 
 # FFmpeg Kit
 -keep class com.arthenica.ffmpegkit.** { *; }
 -keep class com.arthenica.smartexception.** { *; }
+# FFmpeg Kit (new fork package)
+-keep class com.antonkarpenko.ffmpegkit.** { *; }
+-keep class com.antonkarpenko.smartexception.** { *; }
 
 # Apache Tika (if used by FFmpeg)
 -dontwarn org.apache.tika.**
@@ -30,15 +40,77 @@
     native <methods>;
 }
 
-# Kotlin coroutines
+# Kotlin coroutines - expanded rules
 -keepnames class kotlinx.coroutines.internal.MainDispatcherFactory {}
 -keepnames class kotlinx.coroutines.CoroutineExceptionHandler {}
 -keepclassmembers class kotlinx.coroutines.** {
     volatile <fields>;
 }
+-keepclassmembernames class kotlinx.** {
+    volatile <fields>;
+}
+-dontwarn kotlinx.coroutines.**
+
+# Kotlin serialization
+-keepattributes RuntimeVisibleAnnotations,AnnotationDefault
+-dontwarn kotlin.**
+-keep class kotlin.** { *; }
+-keep class kotlin.Metadata { *; }
+
+# Keep MainActivity and related classes
+-keep class com.zarz.spotiflac.** { *; }
 
 # Prevent R8 from removing metadata
 -keepattributes *Annotation*
 -keepattributes SourceFile,LineNumberTable
 -keepattributes Signature
 -keepattributes Exceptions
+-keepattributes InnerClasses
+-keepattributes EnclosingMethod
+
+# JSON parsing (used by Go backend responses)
+-keep class org.json.** { *; }
+
+# Shared Preferences
+-keep class androidx.datastore.** { *; }
+-dontwarn androidx.datastore.**
+
+# Flutter Plugins - CRITICAL: Prevent R8 from removing plugin implementations
+# Path Provider
+-keep class io.flutter.plugins.pathprovider.** { *; }
+-keep class dev.flutter.pigeon.** { *; }
+
+# Local Notifications
+-keep class com.dexterous.** { *; }
+-keep class com.dexterous.flutterlocalnotifications.** { *; }
+
+# Receive Sharing Intent
+-keep class com.kasem.receive_sharing_intent.** { *; }
+
+# Permission Handler
+-keep class com.baseflow.permissionhandler.** { *; }
+
+# File Picker
+-keep class com.mr.flutter.plugin.filepicker.** { *; }
+
+# URL Launcher
+-keep class io.flutter.plugins.urllauncher.** { *; }
+
+# Share Plus
+-keep class dev.fluttercommunity.plus.share.** { *; }
+
+# Device Info Plus
+-keep class dev.fluttercommunity.plus.device_info.** { *; }
+
+# Open File
+-keep class com.crazecoder.openfile.** { *; }
+
+# Sqflite
+-keep class com.tekartik.sqflite.** { *; }
+
+# Dynamic Color
+-keep class io.material.** { *; }
+
+# Keep all Flutter plugin registrants
+-keep class io.flutter.plugins.GeneratedPluginRegistrant { *; }
+-keep class ** extends io.flutter.embedding.engine.plugins.FlutterPlugin { *; }

android/app/src/main/AndroidManifest.xml

@@ -20,9 +20,9 @@
         android:label="SpotiFLAC"
         android:name="${applicationName}"
         android:icon="@mipmap/ic_launcher"
-        android:requestLegacyExternalStorage="true"
-        android:usesCleartextTraffic="true"
-        android:enableOnBackInvokedCallback="true">
+        android:usesCleartextTraffic="false"
+        android:enableOnBackInvokedCallback="true"
+        android:localeConfig="@xml/locale_config">
 
         <activity
             android:name=".MainActivity"
@@ -43,7 +43,7 @@
                 <category android:name="android.intent.category.LAUNCHER"/>
             </intent-filter>
 
-            <!-- Handle Spotify URL sharing -->
+            <!-- Handle music URL sharing (Spotify, Deezer, Tidal, YT Music) -->
             <intent-filter>
                 <action android:name="android.intent.action.SEND" />
                 <category android:name="android.intent.category.DEFAULT" />
@@ -57,6 +57,33 @@
                 <category android:name="android.intent.category.BROWSABLE" />
                 <data android:scheme="https" android:host="open.spotify.com" />
             </intent-filter>
+
+            <!-- Handle Deezer deep links -->
+            <intent-filter android:autoVerify="true">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https" android:host="www.deezer.com" />
+                <data android:scheme="https" android:host="deezer.com" />
+                <data android:scheme="https" android:host="deezer.page.link" />
+            </intent-filter>
+
+            <!-- Handle Tidal deep links -->
+            <intent-filter android:autoVerify="true">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https" android:host="tidal.com" />
+                <data android:scheme="https" android:host="listen.tidal.com" />
+            </intent-filter>
+
+            <!-- Handle YouTube Music deep links -->
+            <intent-filter android:autoVerify="true">
+                <action android:name="android.intent.action.VIEW" />
+                <category android:name="android.intent.category.DEFAULT" />
+                <category android:name="android.intent.category.BROWSABLE" />
+                <data android:scheme="https" android:host="music.youtube.com" />
+            </intent-filter>
         </activity>
 
         <!-- Download Service -->

android/app/src/main/res/xml/locale_config.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<locale-config xmlns:android="http://schemas.android.com/apk/res/android">
+    <locale android:name="en" />
+    <locale android:name="ru" />
+    <locale android:name="es-ES" />
+    <locale android:name="id" />
+    <locale android:name="pt-PT" />
+    <locale android:name="ja" />
+    <locale android:name="tr" />
+    <locale android:name="de" />
+    <locale android:name="fr" />
+    <locale android:name="hi" />
+    <locale android:name="ko" />
+    <locale android:name="nl" />
+    <locale android:name="zh" />
+</locale-config>

android/build.gradle.kts

@@ -22,7 +22,7 @@ subprojects {
             }
             
             // Add desugaring dependency to all Android subprojects
-            project.dependencies.add("coreLibraryDesugaring", "com.android.tools:desugar_jdk_libs:2.1.4")
+            project.dependencies.add("coreLibraryDesugaring", "com.android.tools:desugar_jdk_libs:2.1.5")
         }
         
         tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {

android/gradle.properties

@@ -1,2 +1,2 @@
-org.gradle.jvmargs=-Xmx8G -XX:MaxMetaspaceSize=4G -XX:ReservedCodeCacheSize=512m -XX:+HeapDumpOnOutOfMemoryError
+org.gradle.jvmargs=-Xmx4G -XX:MaxMetaspaceSize=2G -XX:ReservedCodeCacheSize=256m -XX:+HeapDumpOnOutOfMemoryError
 android.useAndroidX=true

android/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-8.14-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.3.1-all.zip

android/settings.gradle.kts

@@ -19,8 +19,8 @@ pluginManagement {
 
 plugins {
     id("dev.flutter.flutter-plugin-loader") version "1.0.0"
-    id("com.android.application") version "8.11.1" apply false
-    id("org.jetbrains.kotlin.android") version "2.3.0" apply false
+    id("com.android.application") version "8.13.2" apply false
+    id("org.jetbrains.kotlin.android") version "2.2.21" apply false
 }
 
 include(":app")

go_backend/amazon.go

@@ -17,6 +17,13 @@ import (
 	"time"
 )
 
+// Amazon API timeout and retry configuration for mobile networks
+const (
+	amazonAPITimeoutMobile = 30 * time.Second // Longer timeout for unstable mobile networks
+	amazonMaxRetries       = 2                // Number of retry attempts
+	amazonRetryDelay       = 500 * time.Millisecond
+)
+
 type AmazonDownloader struct {
 	client *http.Client
 }
@@ -24,6 +31,8 @@ type AmazonDownloader struct {
 var (
 	globalAmazonDownloader *AmazonDownloader
 	amazonDownloaderOnce   sync.Once
+	amazonASINRegex        = regexp.MustCompile(`(?i)^B[0-9A-Z]{9}$`)
+	amazonASINFindRegex    = regexp.MustCompile(`(?i)B[0-9A-Z]{9}`)
 )
 
 // AfkarXYZResponse is the response from AfkarXYZ API
@@ -36,13 +45,10 @@ type AfkarXYZResponse struct {
 	} `json:"data"`
 }
 
-func amazonIsASCIIString(s string) bool {
-	for _, r := range s {
-		if r > 127 {
-			return false
-		}
-	}
-	return true
+// AmazonStreamResponse is the new response format from amazon.afkarxyz.fun/api/track/{asin}
+type AmazonStreamResponse struct {
+	StreamURL     string `json:"streamUrl"`
+	DecryptionKey string `json:"decryptionKey"`
 }
 
 func NewAmazonDownloader() *AmazonDownloader {
@@ -54,43 +60,195 @@ func NewAmazonDownloader() *AmazonDownloader {
 	return globalAmazonDownloader
 }
 
-// downloadFromAfkarXYZ downloads a track using AfkarXYZ API
-// Returns: downloadURL, fileName, error
-func (a *AmazonDownloader) downloadFromAfkarXYZ(amazonURL string) (string, string, error) {
-	// AfkarXYZ API endpoint
-	apiURL := "https://amazon.afkarxyz.fun/convert?url=" + url.QueryEscape(amazonURL)
+// fetchAmazonURLWithRetry fetches from AfkarXYZ API with retry logic for mobile networks.
+// Returns downloadURL, suggested fileName, optional decryptionKey.
+func (a *AmazonDownloader) fetchAmazonURLWithRetry(amazonURL string) (string, string, string, error) {
+	var lastErr error
+	for attempt := 0; attempt <= amazonMaxRetries; attempt++ {
+		if attempt > 0 {
+			delay := amazonRetryDelay * time.Duration(1<<(attempt-1)) // Exponential backoff
+			GoLog("[Amazon] Retry %d/%d after %v...\n", attempt, amazonMaxRetries, delay)
+			time.Sleep(delay)
+		}
 
-	GoLog("[Amazon] Fetching from AfkarXYZ API...\n")
+		downloadURL, fileName, decryptionKey, err := a.doAfkarXYZRequest(amazonURL)
+		if err == nil {
+			return downloadURL, fileName, decryptionKey, nil
+		}
 
-	req, err := http.NewRequest("GET", apiURL, nil)
+		lastErr = err
+		errStr := strings.ToLower(err.Error())
+
+		// Check if error is retryable
+		isRetryable := strings.Contains(errStr, "timeout") ||
+			strings.Contains(errStr, "connection reset") ||
+			strings.Contains(errStr, "connection refused") ||
+			strings.Contains(errStr, "eof") ||
+			strings.Contains(errStr, "status 5") ||
+			strings.Contains(errStr, "status 429") ||
+			strings.Contains(errStr, "http 429")
+
+		if !isRetryable {
+			return "", "", "", err
+		}
+
+		GoLog("[Amazon] Attempt %d failed (retryable): %v\n", attempt+1, err)
+	}
+
+	return "", "", "", fmt.Errorf("all %d attempts failed: %w", amazonMaxRetries+1, lastErr)
+}
+
+func normalizeAmazonASIN(candidate string) string {
+	trimmed := strings.TrimSpace(candidate)
+	if trimmed == "" {
+		return ""
+	}
+
+	if decoded, err := url.QueryUnescape(trimmed); err == nil {
+		trimmed = decoded
+	}
+
+	trimmed = strings.ToUpper(trimmed)
+	if idx := strings.IndexAny(trimmed, "?#&/"); idx >= 0 {
+		trimmed = trimmed[:idx]
+	}
+
+	if amazonASINRegex.MatchString(trimmed) {
+		return trimmed
+	}
+
+	return ""
+}
+
+func extractAmazonASIN(amazonURL string) string {
+	raw := strings.TrimSpace(amazonURL)
+	if raw == "" {
+		return ""
+	}
+
+	parsed, err := url.Parse(raw)
+	if err == nil {
+		query := parsed.Query()
+
+		// Prefer track-level ASIN when URL also contains albumAsin.
+		for _, key := range []string{"trackAsin", "trackasin", "trackASIN", "asin", "ASIN", "i"} {
+			if asin := normalizeAmazonASIN(query.Get(key)); asin != "" {
+				return asin
+			}
+		}
+
+		path := strings.Trim(parsed.Path, "/")
+		if path != "" {
+			segments := strings.Split(path, "/")
+
+			for i := 0; i < len(segments)-1; i++ {
+				segment := strings.ToLower(strings.TrimSpace(segments[i]))
+				if segment == "track" || segment == "tracks" {
+					if asin := normalizeAmazonASIN(segments[i+1]); asin != "" {
+						return asin
+					}
+				}
+			}
+
+			if asin := normalizeAmazonASIN(segments[len(segments)-1]); asin != "" {
+				return asin
+			}
+		}
+	}
+
+	match := amazonASINFindRegex.FindString(strings.ToUpper(raw))
+	return normalizeAmazonASIN(match)
+}
+
+// doAfkarXYZRequest performs a single request to Amazon API.
+// It tries new endpoint first, then falls back to legacy /convert endpoint.
+func (a *AmazonDownloader) doAfkarXYZRequest(amazonURL string) (string, string, string, error) {
+	asin := extractAmazonASIN(amazonURL)
+	if asin != "" {
+		GoLog("[Amazon] Using ASIN: %s\n", asin)
+		downloadURL, fileName, decryptKey, err := a.doAfkarXYZRequestNew(asin)
+		if err == nil {
+			return downloadURL, fileName, decryptKey, nil
+		}
+		GoLog("[Amazon] New API failed for ASIN %s, trying legacy endpoint: %v\n", asin, err)
+	}
+	return a.doAfkarXYZRequestLegacy(amazonURL)
+}
+
+func (a *AmazonDownloader) doAfkarXYZRequestNew(asin string) (string, string, string, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), amazonAPITimeoutMobile)
+	defer cancel()
+
+	apiURL := fmt.Sprintf("https://amazon.afkarxyz.fun/api/track/%s", asin)
+	req, err := http.NewRequestWithContext(ctx, "GET", apiURL, nil)
 	if err != nil {
-		return "", "", fmt.Errorf("failed to create request: %w", err)
+		return "", "", "", fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/144.0.0.0 Safari/537.36")
+
+	resp, err := a.client.Do(req)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to call Amazon API: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return "", "", "", fmt.Errorf("Amazon API returned status %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to read response: %w", err)
+	}
+
+	var apiResp AmazonStreamResponse
+	if err := json.Unmarshal(body, &apiResp); err != nil {
+		return "", "", "", fmt.Errorf("failed to decode response: %w", err)
+	}
+
+	if strings.TrimSpace(apiResp.StreamURL) == "" {
+		return "", "", "", fmt.Errorf("Amazon API returned empty stream URL")
+	}
+
+	fileName := asin + ".m4a"
+	return apiResp.StreamURL, fileName, strings.TrimSpace(apiResp.DecryptionKey), nil
+}
+
+func (a *AmazonDownloader) doAfkarXYZRequestLegacy(amazonURL string) (string, string, string, error) {
+	ctx, cancel := context.WithTimeout(context.Background(), amazonAPITimeoutMobile)
+	defer cancel()
+
+	apiURL := "https://amazon.afkarxyz.fun/convert?url=" + url.QueryEscape(amazonURL)
+	req, err := http.NewRequestWithContext(ctx, "GET", apiURL, nil)
+	if err != nil {
+		return "", "", "", fmt.Errorf("failed to create legacy request: %w", err)
 	}
 
 	req.Header.Set("User-Agent", getRandomUserAgent())
 
 	resp, err := a.client.Do(req)
 	if err != nil {
-		return "", "", fmt.Errorf("failed to call AfkarXYZ API: %w", err)
+		return "", "", "", fmt.Errorf("failed to call legacy AfkarXYZ API: %w", err)
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode != 200 {
-		return "", "", fmt.Errorf("AfkarXYZ API returned status %d", resp.StatusCode)
+		return "", "", "", fmt.Errorf("legacy AfkarXYZ API returned status %d", resp.StatusCode)
 	}
 
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
-		return "", "", fmt.Errorf("failed to read response: %w", err)
+		return "", "", "", fmt.Errorf("failed to read legacy response: %w", err)
 	}
 
 	var apiResp AfkarXYZResponse
 	if err := json.Unmarshal(body, &apiResp); err != nil {
-		return "", "", fmt.Errorf("failed to decode response: %w", err)
+		return "", "", "", fmt.Errorf("failed to decode legacy response: %w", err)
 	}
 
-	if !apiResp.Success || apiResp.Data.DirectLink == "" {
-		return "", "", fmt.Errorf("AfkarXYZ API failed or no download link found")
+	if !apiResp.Success || strings.TrimSpace(apiResp.Data.DirectLink) == "" {
+		return "", "", "", fmt.Errorf("legacy AfkarXYZ API failed or no download link found")
 	}
 
 	fileName := apiResp.Data.FileName
@@ -98,19 +256,30 @@ func (a *AmazonDownloader) downloadFromAfkarXYZ(amazonURL string) (string, strin
 		fileName = "track.flac"
 	}
 
-	// Sanitize filename
 	reg := regexp.MustCompile(`[<>:"/\\|?*]`)
 	fileName = reg.ReplaceAllString(fileName, "")
 
-	GoLog("[Amazon] AfkarXYZ returned: %s (%.2f MB)\n", fileName, float64(apiResp.Data.FileSize)/(1024*1024))
-
-	return apiResp.Data.DirectLink, fileName, nil
+	return apiResp.Data.DirectLink, fileName, "", nil
 }
 
-func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string) error {
+func (a *AmazonDownloader) downloadFromAfkarXYZ(amazonURL string) (string, string, string, error) {
+	GoLog("[Amazon] Fetching from AfkarXYZ API...\n")
+
+	downloadURL, fileName, decryptionKey, err := a.fetchAmazonURLWithRetry(amazonURL)
+	if err != nil {
+		return "", "", "", err
+	}
+
+	if decryptionKey != "" {
+		GoLog("[Amazon] AfkarXYZ returned encrypted stream (decryption key available)\n")
+	}
+	GoLog("[Amazon] AfkarXYZ returned: %s\n", fileName)
+	return downloadURL, fileName, decryptionKey, nil
+}
+
+func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath string, outputFD int, itemID string) error {
 	ctx := context.Background()
 
-	// Initialize item progress (required for all downloads)
 	if itemID != "" {
 		StartItemProgress(itemID)
 		defer CompleteItemProgress(itemID)
@@ -147,7 +316,7 @@ func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string)
 		SetItemBytesTotal(itemID, expectedSize)
 	}
 
-	out, err := os.Create(outputPath)
+	out, err := openOutputForWrite(outputPath, outputFD)
 	if err != nil {
 		return err
 	}
@@ -162,29 +331,27 @@ func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string)
 		written, err = io.Copy(bufWriter, resp.Body)
 	}
 
-	// Flush buffer before checking for errors
 	flushErr := bufWriter.Flush()
 	closeErr := out.Close()
 
 	if err != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		if isDownloadCancelled(itemID) {
 			return ErrDownloadCancelled
 		}
 		return fmt.Errorf("download interrupted: %w", err)
 	}
 	if flushErr != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("failed to flush buffer: %w", flushErr)
 	}
 	if closeErr != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("failed to close file: %w", closeErr)
 	}
 
-	// Verify file size if Content-Length was provided
 	if expectedSize > 0 && written != expectedSize {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("incomplete download: expected %d bytes, got %d bytes", expectedSize, written)
 	}
 
@@ -194,55 +361,74 @@ func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string)
 
 // AmazonDownloadResult contains download result with quality info
 type AmazonDownloadResult struct {
-	FilePath    string
-	BitDepth    int
-	SampleRate  int
-	Title       string
-	Artist      string
-	Album       string
-	ReleaseDate string
-	TrackNumber int
-	DiscNumber  int
-	ISRC        string
+	FilePath      string
+	BitDepth      int
+	SampleRate    int
+	Title         string
+	Artist        string
+	Album         string
+	ReleaseDate   string
+	TrackNumber   int
+	DiscNumber    int
+	ISRC          string
+	LyricsLRC     string
+	DecryptionKey string
 }
 
-// downloadFromAmazon uses AfkarXYZ API to download from Amazon Music
 func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 	downloader := NewAmazonDownloader()
 
-	if existingFile, exists := checkISRCExistsInternal(req.OutputDir, req.ISRC); exists {
-		return AmazonDownloadResult{FilePath: "EXISTS:" + existingFile}, nil
+	isSafOutput := isFDOutput(req.OutputFD) || strings.TrimSpace(req.OutputPath) != ""
+	if !isSafOutput {
+		if existingFile, exists := checkISRCExistsInternal(req.OutputDir, req.ISRC); exists {
+			return AmazonDownloadResult{FilePath: "EXISTS:" + existingFile}, nil
+		}
+	}
+
+	amazonURL := ""
+	if req.ISRC != "" {
+		if cached := GetTrackIDCache().Get(req.ISRC); cached != nil && cached.AmazonURL != "" {
+			amazonURL = cached.AmazonURL
+			GoLog("[Amazon] Cache hit! Using cached Amazon URL for ISRC %s\n", req.ISRC)
+		}
 	}
 
 	songlink := NewSongLinkClient()
 	var availability *TrackAvailability
 	var err error
 
-	if deezerID, found := strings.CutPrefix(req.SpotifyID, "deezer:"); found {
-		GoLog("[Amazon] Using Deezer ID for SongLink lookup: %s\n", deezerID)
-		availability, err = songlink.CheckAvailabilityFromDeezer(deezerID)
-	} else if req.SpotifyID != "" {
-		availability, err = songlink.CheckTrackAvailability(req.SpotifyID, req.ISRC)
-	} else {
-		return AmazonDownloadResult{}, fmt.Errorf("no valid Spotify or Deezer ID provided for Amazon lookup")
+	if amazonURL == "" {
+		if deezerID, found := strings.CutPrefix(req.SpotifyID, "deezer:"); found {
+			GoLog("[Amazon] Using Deezer ID for SongLink lookup: %s\n", deezerID)
+			availability, err = songlink.CheckAvailabilityFromDeezer(deezerID)
+		} else if req.SpotifyID != "" {
+			availability, err = songlink.CheckTrackAvailability(req.SpotifyID, req.ISRC)
+		} else {
+			return AmazonDownloadResult{}, fmt.Errorf("no valid Spotify or Deezer ID provided for Amazon lookup")
+		}
+
+		if err != nil {
+			return AmazonDownloadResult{}, fmt.Errorf("failed to check Amazon availability via SongLink: %w", err)
+		}
+
+		if !availability.Amazon || availability.AmazonURL == "" {
+			return AmazonDownloadResult{}, fmt.Errorf("track not available on Amazon Music (SongLink returned no Amazon URL)")
+		}
+
+		amazonURL = availability.AmazonURL
+		if req.ISRC != "" {
+			GetTrackIDCache().SetAmazonURL(req.ISRC, amazonURL)
+		}
 	}
 
-	if err != nil {
-		return AmazonDownloadResult{}, fmt.Errorf("failed to check Amazon availability via SongLink: %w", err)
-	}
-
-	if !availability.Amazon || availability.AmazonURL == "" {
-		return AmazonDownloadResult{}, fmt.Errorf("track not available on Amazon Music (SongLink returned no Amazon URL)")
-	}
-
-	if req.OutputDir != "." {
+	if !isSafOutput && req.OutputDir != "." {
 		if err := os.MkdirAll(req.OutputDir, 0755); err != nil {
 			return AmazonDownloadResult{}, fmt.Errorf("failed to create output directory: %w", err)
 		}
 	}
 
 	// Download using AfkarXYZ API
-	downloadURL, _, err := downloader.downloadFromAfkarXYZ(availability.AmazonURL)
+	downloadURL, afkarFileName, decryptionKey, err := downloader.downloadFromAfkarXYZ(amazonURL)
 	if err != nil {
 		return AmazonDownloadResult{}, fmt.Errorf("failed to get download URL from AfkarXYZ: %w", err)
 	}
@@ -255,13 +441,25 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		"album":  req.AlbumName,
 		"track":  req.TrackNumber,
 		"year":   extractYear(req.ReleaseDate),
+		"date":   req.ReleaseDate,
 		"disc":   req.DiscNumber,
 	})
-	filename = sanitizeFilename(filename) + ".flac"
-	outputPath := filepath.Join(req.OutputDir, filename)
-
-	if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
-		return AmazonDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
+	var outputPath string
+	if isSafOutput {
+		outputPath = strings.TrimSpace(req.OutputPath)
+		if outputPath == "" && isFDOutput(req.OutputFD) {
+			outputPath = fmt.Sprintf("/proc/self/fd/%d", req.OutputFD)
+		}
+	} else {
+		outputExt := strings.ToLower(filepath.Ext(afkarFileName))
+		if outputExt == "" {
+			outputExt = ".flac"
+		}
+		filename = sanitizeFilename(filename) + outputExt
+		outputPath = filepath.Join(req.OutputDir, filename)
+		if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
+			return AmazonDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
+		}
 	}
 
 	// START PARALLEL: Fetch cover and lyrics while downloading audio
@@ -281,13 +479,19 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 	}()
 
 	// Download audio file with item ID for progress tracking
-	if err := downloader.DownloadFile(downloadURL, outputPath, req.ItemID); err != nil {
+	if err := downloader.DownloadFile(downloadURL, outputPath, req.OutputFD, req.ItemID); err != nil {
 		if errors.Is(err, ErrDownloadCancelled) {
 			return AmazonDownloadResult{}, ErrDownloadCancelled
 		}
 		return AmazonDownloadResult{}, fmt.Errorf("download failed: %w", err)
 	}
 
+	actualOutputPath := outputPath
+	needsDecryption := strings.TrimSpace(decryptionKey) != ""
+	if needsDecryption {
+		GoLog("[Amazon] Download requires decryption; deferring decrypt to Flutter FFmpeg path\n")
+	}
+
 	// Wait for parallel operations to complete
 	<-parallelDone
 
@@ -296,28 +500,43 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		SetItemFinalizing(req.ItemID)
 	}
 
-	existingMeta, metaErr := ReadMetadata(outputPath)
 	actualTrackNum := req.TrackNumber
 	actualDiscNum := req.DiscNumber
+	actualDate := req.ReleaseDate
+	actualAlbum := req.AlbumName
+	actualTitle := req.TrackName
+	actualArtist := req.ArtistName
 
-	if metaErr == nil && existingMeta != nil {
-		if existingMeta.TrackNumber > 0 && (req.TrackNumber == 0 || req.TrackNumber == 1) {
-			actualTrackNum = existingMeta.TrackNumber
-			GoLog("[Amazon] Using track number from file: %d (request had: %d)\n", actualTrackNum, req.TrackNumber)
-		}
-		if existingMeta.DiscNumber > 0 && (req.DiscNumber == 0 || req.DiscNumber == 1) {
-			actualDiscNum = existingMeta.DiscNumber
-			GoLog("[Amazon] Using disc number from file: %d (request had: %d)\n", actualDiscNum, req.DiscNumber)
+	if !needsDecryption {
+		existingMeta, metaErr := ReadMetadata(actualOutputPath)
+		if metaErr == nil && existingMeta != nil {
+			if existingMeta.TrackNumber > 0 && (req.TrackNumber == 0 || req.TrackNumber == 1) {
+				actualTrackNum = existingMeta.TrackNumber
+				GoLog("[Amazon] Using track number from file: %d (request had: %d)\n", actualTrackNum, req.TrackNumber)
+			}
+			if existingMeta.DiscNumber > 0 && (req.DiscNumber == 0 || req.DiscNumber == 1) {
+				actualDiscNum = existingMeta.DiscNumber
+				GoLog("[Amazon] Using disc number from file: %d (request had: %d)\n", actualDiscNum, req.DiscNumber)
+			}
+			if existingMeta.Date != "" && req.ReleaseDate == "" {
+				actualDate = existingMeta.Date
+				GoLog("[Amazon] Using release date from file: %s\n", actualDate)
+			}
+			if existingMeta.Album != "" && req.AlbumName == "" {
+				actualAlbum = existingMeta.Album
+				GoLog("[Amazon] Using album from file: %s\n", actualAlbum)
+			}
+			GoLog("[Amazon] Existing metadata - Title: %s, Artist: %s, Album: %s, Date: %s\n",
+				existingMeta.Title, existingMeta.Artist, existingMeta.Album, existingMeta.Date)
 		}
 	}
 
-	// Embed metadata using Spotify data
 	metadata := Metadata{
-		Title:       req.TrackName,
-		Artist:      req.ArtistName,
-		Album:       req.AlbumName,
+		Title:       actualTitle,
+		Artist:      actualArtist,
+		Album:       actualAlbum,
 		AlbumArtist: req.AlbumArtist,
-		Date:        req.ReleaseDate,
+		Date:        actualDate,
 		TrackNumber: actualTrackNum,
 		TotalTracks: req.TotalTracks,
 		DiscNumber:  actualDiscNum,
@@ -327,66 +546,92 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		Copyright:   req.Copyright,
 	}
 
-	// Use cover data from parallel fetch
 	var coverData []byte
-	if parallelResult != nil && parallelResult.CoverData != nil {
+	if parallelResult != nil && parallelResult.CoverData != nil && len(parallelResult.CoverData) > 0 {
 		coverData = parallelResult.CoverData
 		GoLog("[Amazon] Using parallel-fetched cover (%d bytes)\n", len(coverData))
+	} else {
+		existingCover, coverErr := ExtractCoverArt(actualOutputPath)
+		if coverErr == nil && len(existingCover) > 0 {
+			coverData = existingCover
+			GoLog("[Amazon] Using existing cover from Amazon file (%d bytes)\n", len(coverData))
+		} else {
+			GoLog("[Amazon] No cover available (parallel fetch failed and no existing cover)\n")
+		}
 	}
 
-	if err := EmbedMetadataWithCoverData(outputPath, metadata, coverData); err != nil {
-		GoLog("[Amazon] Warning: failed to embed metadata: %v\n", err)
-	}
-
-	if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
-		lyricsMode := req.LyricsMode
-		if lyricsMode == "" {
-			lyricsMode = "embed" // default
-		}
-
-		if lyricsMode == "external" || lyricsMode == "both" {
-			GoLog("[Amazon] Saving external LRC file...\n")
-			if lrcPath, lrcErr := SaveLRCFile(outputPath, parallelResult.LyricsLRC); lrcErr != nil {
-				GoLog("[Amazon] Warning: failed to save LRC file: %v\n", lrcErr)
-			} else {
-				GoLog("[Amazon] LRC file saved: %s\n", lrcPath)
+	if isSafOutput || needsDecryption {
+		GoLog("[Amazon] SAF output detected - skipping in-backend metadata/lyrics embedding (handled in Flutter)\n")
+	} else {
+		isFlacOutput := strings.HasSuffix(strings.ToLower(actualOutputPath), ".flac")
+		if isFlacOutput {
+			if err := EmbedMetadataWithCoverData(actualOutputPath, metadata, coverData); err != nil {
+				GoLog("[Amazon] Warning: failed to embed metadata: %v\n", err)
 			}
+		} else {
+			GoLog("[Amazon] Non-FLAC output detected (%s), skipping native metadata embedding\n", filepath.Ext(actualOutputPath))
 		}
 
-		if lyricsMode == "embed" || lyricsMode == "both" {
-			GoLog("[Amazon] Embedding parallel-fetched lyrics (%d lines)...\n", len(parallelResult.LyricsData.Lines))
-			if embedErr := EmbedLyrics(outputPath, parallelResult.LyricsLRC); embedErr != nil {
-				GoLog("[Amazon] Warning: failed to embed lyrics: %v\n", embedErr)
-			} else {
-				GoLog("[Amazon] Lyrics embedded successfully\n")
+		if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
+			lyricsMode := req.LyricsMode
+			if lyricsMode == "" {
+				lyricsMode = "embed"
 			}
+
+			if lyricsMode == "external" || lyricsMode == "both" {
+				GoLog("[Amazon] Saving external LRC file...\n")
+				if lrcPath, lrcErr := SaveLRCFile(actualOutputPath, parallelResult.LyricsLRC); lrcErr != nil {
+					GoLog("[Amazon] Warning: failed to save LRC file: %v\n", lrcErr)
+				} else {
+					GoLog("[Amazon] LRC file saved: %s\n", lrcPath)
+				}
+			}
+
+			if (lyricsMode == "embed" || lyricsMode == "both") && isFlacOutput {
+				GoLog("[Amazon] Embedding parallel-fetched lyrics (%d lines)...\n", len(parallelResult.LyricsData.Lines))
+				if embedErr := EmbedLyrics(actualOutputPath, parallelResult.LyricsLRC); embedErr != nil {
+					GoLog("[Amazon] Warning: failed to embed lyrics: %v\n", embedErr)
+				} else {
+					GoLog("[Amazon] Lyrics embedded successfully\n")
+				}
+			} else if (lyricsMode == "embed" || lyricsMode == "both") && !isFlacOutput {
+				GoLog("[Amazon] Skipping embedded lyrics for non-FLAC output\n")
+			}
+		} else if req.EmbedLyrics {
+			GoLog("[Amazon] No lyrics available from parallel fetch\n")
 		}
-	} else if req.EmbedLyrics {
-		GoLog("[Amazon] No lyrics available from parallel fetch\n")
 	}
 
 	GoLog("[Amazon] Downloaded successfully from Amazon Music\n")
 
-	quality, err := GetAudioQuality(outputPath)
-	if err != nil {
-		GoLog("[Amazon] Warning: couldn't read quality from file: %v\n", err)
+	quality := AudioQuality{}
+	if isSafOutput || needsDecryption {
+		GoLog("[Amazon] SAF output detected - skipping post-write file inspection in backend\n")
 	} else {
-		GoLog("[Amazon] Actual quality: %d-bit/%dHz\n", quality.BitDepth, quality.SampleRate)
-	}
+		quality, err = GetAudioQuality(actualOutputPath)
+		if err != nil {
+			GoLog("[Amazon] Warning: couldn't read quality from file: %v\n", err)
+		} else {
+			GoLog("[Amazon] Actual quality: %d-bit/%dHz\n", quality.BitDepth, quality.SampleRate)
+		}
 
-	finalMeta, metaReadErr := ReadMetadata(outputPath)
-	if metaReadErr == nil && finalMeta != nil {
-		GoLog("[Amazon] Final metadata from file - Track: %d, Disc: %d, Date: %s\n",
-			finalMeta.TrackNumber, finalMeta.DiscNumber, finalMeta.Date)
-		actualTrackNum = finalMeta.TrackNumber
-		actualDiscNum = finalMeta.DiscNumber
-		if finalMeta.Date != "" {
-			req.ReleaseDate = finalMeta.Date
+		finalMeta, metaReadErr := ReadMetadata(actualOutputPath)
+		if metaReadErr == nil && finalMeta != nil {
+			GoLog("[Amazon] Final metadata from file - Track: %d, Disc: %d, Date: %s\n",
+				finalMeta.TrackNumber, finalMeta.DiscNumber, finalMeta.Date)
+			actualTrackNum = finalMeta.TrackNumber
+			actualDiscNum = finalMeta.DiscNumber
+			if finalMeta.Date != "" {
+				req.ReleaseDate = finalMeta.Date
+			}
 		}
 	}
 
-	// Add to ISRC index for fast duplicate checking
-	AddToISRCIndex(req.OutputDir, req.ISRC, outputPath)
+	// Add to ISRC index for fast duplicate checking.
+	// When decryption is pending in Flutter, postpone indexing until final file is settled.
+	if !isSafOutput && !needsDecryption {
+		AddToISRCIndex(req.OutputDir, req.ISRC, actualOutputPath)
+	}
 
 	bitDepth := 0
 	sampleRate := 0
@@ -395,16 +640,23 @@ func downloadFromAmazon(req DownloadRequest) (AmazonDownloadResult, error) {
 		sampleRate = quality.SampleRate
 	}
 
+	lyricsLRC := ""
+	if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
+		lyricsLRC = parallelResult.LyricsLRC
+	}
+
 	return AmazonDownloadResult{
-		FilePath:    outputPath,
-		BitDepth:    bitDepth,
-		SampleRate:  sampleRate,
-		Title:       req.TrackName,
-		Artist:      req.ArtistName,
-		Album:       req.AlbumName,
-		ReleaseDate: req.ReleaseDate,
-		TrackNumber: actualTrackNum,
-		DiscNumber:  actualDiscNum,
-		ISRC:        req.ISRC,
+		FilePath:      outputPath,
+		BitDepth:      bitDepth,
+		SampleRate:    sampleRate,
+		Title:         req.TrackName,
+		Artist:        req.ArtistName,
+		Album:         req.AlbumName,
+		ReleaseDate:   req.ReleaseDate,
+		TrackNumber:   actualTrackNum,
+		DiscNumber:    actualDiscNum,
+		ISRC:          req.ISRC,
+		LyricsLRC:     lyricsLRC,
+		DecryptionKey: decryptionKey,
 	}, nil
 }

go_backend/amazon_asin_test.go

@@ -0,0 +1,46 @@
+package gobackend
+
+import "testing"
+
+func TestExtractAmazonASIN(t *testing.T) {
+	tests := []struct {
+		name string
+		url  string
+		want string
+	}{
+		{
+			name: "prefers trackAsin over albumAsin",
+			url:  "https://music.amazon.com/albums/B0ALBUM123?trackAsin=B0TRACK456&musicTerritory=US",
+			want: "B0TRACK456",
+		},
+		{
+			name: "extract from tracks path",
+			url:  "https://music.amazon.com/tracks/B0CYQHGWZJ?musicTerritory=US",
+			want: "B0CYQHGWZJ",
+		},
+		{
+			name: "extract from plain query asin",
+			url:  "https://example.com/?asin=B0CYQHGWZJ",
+			want: "B0CYQHGWZJ",
+		},
+		{
+			name: "fallback regex",
+			url:  "https://example.com/path/B0CYQHGWZJ",
+			want: "B0CYQHGWZJ",
+		},
+		{
+			name: "invalid url",
+			url:  "https://music.amazon.com/tracks/not-valid",
+			want: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := extractAmazonASIN(tt.url)
+			if got != tt.want {
+				t.Fatalf("extractAmazonASIN() = %q, want %q", got, tt.want)
+			}
+		})
+	}
+}

go_backend/deezer.go

@@ -23,15 +23,28 @@ const (
 	deezerCacheTTL = 10 * time.Minute
 
 	deezerMaxParallelISRC = 10
+
+	// Deezer API timeout and retry configuration for mobile networks
+	deezerAPITimeoutMobile = 25 * time.Second
+	deezerMaxRetries       = 2
+	deezerRetryDelay       = 500 * time.Millisecond
+
+	deezerMaxSearchCacheEntries = 300
+	deezerMaxAlbumCacheEntries  = 200
+	deezerMaxArtistCacheEntries = 200
+	deezerMaxISRCCacheEntries   = 4000
+	deezerCacheCleanupInterval  = 5 * time.Minute
 )
 
 type DeezerClient struct {
-	httpClient  *http.Client
-	searchCache map[string]*cacheEntry
-	albumCache  map[string]*cacheEntry
-	artistCache map[string]*cacheEntry
-	isrcCache   map[string]string
-	cacheMu     sync.RWMutex
+	httpClient           *http.Client
+	searchCache          map[string]*cacheEntry
+	albumCache           map[string]*cacheEntry
+	artistCache          map[string]*cacheEntry
+	isrcCache            map[string]string
+	cacheMu              sync.RWMutex
+	lastCacheCleanup     time.Time
+	cacheCleanupInterval time.Duration
 }
 
 var (
@@ -42,20 +55,115 @@ var (
 func GetDeezerClient() *DeezerClient {
 	deezerClientOnce.Do(func() {
 		deezerClient = &DeezerClient{
-			httpClient:  NewHTTPClientWithTimeout(15 * time.Second),
-			searchCache: make(map[string]*cacheEntry),
-			albumCache:  make(map[string]*cacheEntry),
-			artistCache: make(map[string]*cacheEntry),
-			isrcCache:   make(map[string]string),
+			httpClient:           NewMetadataHTTPClient(deezerAPITimeoutMobile),
+			searchCache:          make(map[string]*cacheEntry),
+			albumCache:           make(map[string]*cacheEntry),
+			artistCache:          make(map[string]*cacheEntry),
+			isrcCache:            make(map[string]string),
+			cacheCleanupInterval: deezerCacheCleanupInterval,
 		}
 	})
 	return deezerClient
 }
 
+func (c *DeezerClient) pruneExpiredCacheEntriesLocked(
+	cache map[string]*cacheEntry,
+	now time.Time,
+) {
+	for key, entry := range cache {
+		if entry == nil || now.After(entry.expiresAt) {
+			delete(cache, key)
+		}
+	}
+}
+
+func (c *DeezerClient) trimCacheEntriesLocked(
+	cache map[string]*cacheEntry,
+	maxEntries int,
+) {
+	if maxEntries <= 0 || len(cache) <= maxEntries {
+		return
+	}
+
+	for len(cache) > maxEntries {
+		var oldestKey string
+		var oldestExpiry time.Time
+		first := true
+		for key, entry := range cache {
+			expiry := time.Time{}
+			if entry != nil {
+				expiry = entry.expiresAt
+			}
+			if first || expiry.Before(oldestExpiry) {
+				first = false
+				oldestKey = key
+				oldestExpiry = expiry
+			}
+		}
+		if oldestKey == "" {
+			return
+		}
+		delete(cache, oldestKey)
+	}
+}
+
+func (c *DeezerClient) trimStringCacheEntriesLocked(
+	cache map[string]string,
+	maxEntries int,
+) {
+	if maxEntries <= 0 || len(cache) <= maxEntries {
+		return
+	}
+
+	toRemove := len(cache) - maxEntries
+	for key := range cache {
+		delete(cache, key)
+		toRemove--
+		if toRemove <= 0 {
+			return
+		}
+	}
+}
+
+func (c *DeezerClient) maybeCleanupCachesLocked(now time.Time) {
+	periodicCleanupDue := c.cacheCleanupInterval > 0 &&
+		(c.lastCacheCleanup.IsZero() ||
+			now.Sub(c.lastCacheCleanup) >= c.cacheCleanupInterval)
+
+	if periodicCleanupDue {
+		c.pruneExpiredCacheEntriesLocked(c.searchCache, now)
+		c.pruneExpiredCacheEntriesLocked(c.albumCache, now)
+		c.pruneExpiredCacheEntriesLocked(c.artistCache, now)
+		c.lastCacheCleanup = now
+	}
+
+	if len(c.searchCache) > deezerMaxSearchCacheEntries {
+		if !periodicCleanupDue {
+			c.pruneExpiredCacheEntriesLocked(c.searchCache, now)
+		}
+		c.trimCacheEntriesLocked(c.searchCache, deezerMaxSearchCacheEntries)
+	}
+	if len(c.albumCache) > deezerMaxAlbumCacheEntries {
+		if !periodicCleanupDue {
+			c.pruneExpiredCacheEntriesLocked(c.albumCache, now)
+		}
+		c.trimCacheEntriesLocked(c.albumCache, deezerMaxAlbumCacheEntries)
+	}
+	if len(c.artistCache) > deezerMaxArtistCacheEntries {
+		if !periodicCleanupDue {
+			c.pruneExpiredCacheEntriesLocked(c.artistCache, now)
+		}
+		c.trimCacheEntriesLocked(c.artistCache, deezerMaxArtistCacheEntries)
+	}
+	if len(c.isrcCache) > deezerMaxISRCCacheEntries {
+		c.trimStringCacheEntriesLocked(c.isrcCache, deezerMaxISRCCacheEntries)
+	}
+}
+
 type deezerTrack struct {
 	ID            int64             `json:"id"`
 	Title         string            `json:"title"`
-	Duration      int               `json:"duration"` // in seconds
+	Duration      int               `json:"duration"`
 	TrackPosition int               `json:"track_position"`
 	DiskNumber    int               `json:"disk_number"`
 	ISRC          string            `json:"isrc"`
@@ -121,7 +229,7 @@ func (c *DeezerClient) convertTrack(track deezerTrack) TrackMetadata {
 		AlbumArtist: track.Artist.Name,
 		DurationMS:  track.Duration * 1000,
 		Images:      albumImage,
-		ReleaseDate: releaseDate, // Added this
+		ReleaseDate: releaseDate,
 		TrackNumber: track.TrackPosition,
 		DiscNumber:  track.DiskNumber,
 		ExternalURL: track.Link,
@@ -182,15 +290,12 @@ type deezerPlaylistFull struct {
 	} `json:"tracks"`
 }
 
-// NOTE: ISRC is NOT fetched during search for performance - use GetTrackISRC when needed for download
-// filter can be: "" (all), "track", "artist", "album", "playlist"
 func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit, artistLimit int, filter string) (*SearchAllResult, error) {
 	GoLog("[Deezer] SearchAll: query=%q, trackLimit=%d, artistLimit=%d, filter=%q\n", query, trackLimit, artistLimit, filter)
 
-	albumLimit := 5 // Same as artistLimit for consistency
+	albumLimit := 5
 	playlistLimit := 5
 
-	// When filter is specified, increase limits for that type only
 	if filter != "" {
 		switch filter {
 		case "track":
@@ -233,7 +338,6 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 		Playlists: make([]SearchPlaylistResult, 0, playlistLimit),
 	}
 
-	// Search tracks - NO ISRC fetch for performance
 	if trackLimit > 0 {
 		trackURL := fmt.Sprintf("%s/track?q=%s&limit=%d", deezerSearchURL, url.QueryEscape(query), trackLimit)
 		GoLog("[Deezer] Fetching tracks from: %s\n", trackURL)
@@ -263,7 +367,6 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 		}
 	}
 
-	// Search artists
 	if artistLimit > 0 {
 		artistURL := fmt.Sprintf("%s/artist?q=%s&limit=%d", deezerSearchURL, url.QueryEscape(query), artistLimit)
 		GoLog("[Deezer] Fetching artists from: %s\n", artistURL)
@@ -296,7 +399,6 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 		}
 	}
 
-	// Search albums
 	if albumLimit > 0 {
 		albumURL := fmt.Sprintf("%s/album?q=%s&limit=%d", deezerSearchURL, url.QueryEscape(query), albumLimit)
 		GoLog("[Deezer] Fetching albums from: %s\n", albumURL)
@@ -358,7 +460,6 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 		}
 	}
 
-	// Search playlists
 	if playlistLimit > 0 {
 		playlistURL := fmt.Sprintf("%s/playlist?q=%s&limit=%d", deezerSearchURL, url.QueryEscape(query), playlistLimit)
 		GoLog("[Deezer] Fetching playlists from: %s\n", playlistURL)
@@ -416,16 +517,17 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 	GoLog("[Deezer] SearchAll complete: %d tracks, %d artists, %d albums, %d playlists\n", len(result.Tracks), len(result.Artists), len(result.Albums), len(result.Playlists))
 
 	c.cacheMu.Lock()
+	now := time.Now()
 	c.searchCache[cacheKey] = &cacheEntry{
 		data:      result,
-		expiresAt: time.Now().Add(deezerCacheTTL),
+		expiresAt: now.Add(deezerCacheTTL),
 	}
+	c.maybeCleanupCachesLocked(now)
 	c.cacheMu.Unlock()
 
 	return result, nil
 }
 
-// GetTrack fetches a single track by Deezer ID
 func (c *DeezerClient) GetTrack(ctx context.Context, trackID string) (*TrackResponse, error) {
 	trackURL := fmt.Sprintf(deezerTrackURL, trackID)
 
@@ -439,7 +541,6 @@ func (c *DeezerClient) GetTrack(ctx context.Context, trackID string) (*TrackResp
 	}, nil
 }
 
-// ISRC is fetched in parallel for better performance
 func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResponsePayload, error) {
 	c.cacheMu.RLock()
 	if entry, ok := c.albumCache[albumID]; ok && !entry.isExpired() {
@@ -465,7 +566,6 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 		artistName = strings.Join(names, ", ")
 	}
 
-	// Extract genres as comma-separated string
 	var genres []string
 	for _, g := range album.Genres.Data {
 		if g.Name != "" {
@@ -481,14 +581,12 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 		Artists:     artistName,
 		ArtistId:    fmt.Sprintf("deezer:%d", album.Artist.ID),
 		Images:      albumImage,
-		Genre:       genreStr,    // From Deezer album
-		Label:       album.Label, // From Deezer album
+		Genre:       genreStr,
+		Label:       album.Label,
 	}
 
-	// Fetch all tracks with pagination (Deezer default limit is 25)
 	allTracks := album.Tracks.Data
 
-	// If album has more tracks than returned, fetch remaining pages
 	if album.NbTracks > len(allTracks) {
 		GoLog("[Deezer] Album has %d tracks but only got %d, fetching remaining...", album.NbTracks, len(allTracks))
 
@@ -523,7 +621,6 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 	isrcMap := c.fetchISRCsParallel(ctx, allTracks)
 
 	tracks := make([]AlbumTrackMetadata, 0, len(allTracks))
-	// Normalize record_type (Deezer uses "compile" instead of "compilation")
 	albumType := album.RecordType
 	if albumType == "compile" {
 		albumType = "compilation"
@@ -533,7 +630,6 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 		trackIDStr := fmt.Sprintf("%d", track.ID)
 		isrc := isrcMap[trackIDStr]
 
-		// Use track position from API, fallback to index+1 if not provided
 		trackNum := track.TrackPosition
 		if trackNum == 0 {
 			trackNum = i + 1
@@ -564,10 +660,12 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 	}
 
 	c.cacheMu.Lock()
+	now := time.Now()
 	c.albumCache[albumID] = &cacheEntry{
 		data:      result,
-		expiresAt: time.Now().Add(deezerCacheTTL),
+		expiresAt: now.Add(deezerCacheTTL),
 	}
+	c.maybeCleanupCachesLocked(now)
 	c.cacheMu.Unlock()
 
 	return result, nil
@@ -581,7 +679,6 @@ func (c *DeezerClient) GetArtist(ctx context.Context, artistID string) (*ArtistR
 	}
 	c.cacheMu.RUnlock()
 
-	// Fetch artist info
 	artistURL := fmt.Sprintf(deezerArtistURL, artistID)
 	var artist deezerArtistFull
 	if err := c.getJSON(ctx, artistURL, &artist); err != nil {
@@ -596,7 +693,6 @@ func (c *DeezerClient) GetArtist(ctx context.Context, artistID string) (*ArtistR
 		Popularity: 0,
 	}
 
-	// Fetch artist albums
 	albumsURL := fmt.Sprintf("%s/albums?limit=100", fmt.Sprintf(deezerArtistURL, artistID))
 	var albumsResp struct {
 		Data []struct {
@@ -608,7 +704,7 @@ func (c *DeezerClient) GetArtist(ctx context.Context, artistID string) (*ArtistR
 			CoverMedium string `json:"cover_medium"`
 			CoverBig    string `json:"cover_big"`
 			CoverXL     string `json:"cover_xl"`
-			RecordType  string `json:"record_type"` // album, single, ep, compile
+			RecordType  string `json:"record_type"`
 		} `json:"data"`
 	}
 
@@ -649,10 +745,12 @@ func (c *DeezerClient) GetArtist(ctx context.Context, artistID string) (*ArtistR
 	}
 
 	c.cacheMu.Lock()
+	now := time.Now()
 	c.artistCache[artistID] = &cacheEntry{
 		data:      result,
-		expiresAt: time.Now().Add(deezerCacheTTL),
+		expiresAt: now.Add(deezerCacheTTL),
 	}
+	c.maybeCleanupCachesLocked(now)
 	c.cacheMu.Unlock()
 
 	return result, nil
@@ -680,10 +778,8 @@ func (c *DeezerClient) GetPlaylist(ctx context.Context, playlistID string) (*Pla
 	info.Owner.Name = playlist.Title
 	info.Owner.Images = playlistImage
 
-	// Fetch all tracks with pagination (Deezer default limit is 25)
 	allTracks := playlist.Tracks.Data
 
-	// If playlist has more tracks than returned, fetch remaining pages
 	if playlist.NbTracks > len(allTracks) {
 		GoLog("[Deezer] Playlist has %d tracks but only got %d, fetching remaining...", playlist.NbTracks, len(allTracks))
 
@@ -789,7 +885,6 @@ func (c *DeezerClient) fetchFullTrack(ctx context.Context, trackID string) (*dee
 	return &track, nil
 }
 
-// fetchISRCsParallel fetches ISRCs for multiple tracks in parallel with caching
 func (c *DeezerClient) fetchISRCsParallel(ctx context.Context, tracks []deezerTrack) map[string]string {
 	result := make(map[string]string, len(tracks))
 	var resultMu sync.Mutex
@@ -821,6 +916,7 @@ func (c *DeezerClient) fetchISRCsParallel(ctx context.Context, tracks []deezerTr
 		for trackIDStr, isrc := range directISRCs {
 			c.isrcCache[trackIDStr] = isrc
 		}
+		c.maybeCleanupCachesLocked(time.Now())
 		c.cacheMu.Unlock()
 	}
 
@@ -828,7 +924,6 @@ func (c *DeezerClient) fetchISRCsParallel(ctx context.Context, tracks []deezerTr
 		return result
 	}
 
-	// Use semaphore to limit concurrent requests
 	sem := make(chan struct{}, deezerMaxParallelISRC)
 	var wg sync.WaitGroup
 
@@ -850,13 +945,13 @@ func (c *DeezerClient) fetchISRCsParallel(ctx context.Context, tracks []deezerTr
 				return
 			}
 
-			// Store in result and cache
 			resultMu.Lock()
 			result[trackIDStr] = fullTrack.ISRC
 			resultMu.Unlock()
 
 			c.cacheMu.Lock()
 			c.isrcCache[trackIDStr] = fullTrack.ISRC
+			c.maybeCleanupCachesLocked(time.Now())
 			c.cacheMu.Unlock()
 		}(track)
 	}
@@ -865,7 +960,6 @@ func (c *DeezerClient) fetchISRCsParallel(ctx context.Context, tracks []deezerTr
 	return result
 }
 
-// Use this when you need ISRC for download
 func (c *DeezerClient) GetTrackISRC(ctx context.Context, trackID string) (string, error) {
 	c.cacheMu.RLock()
 	if isrc, ok := c.isrcCache[trackID]; ok {
@@ -881,6 +975,7 @@ func (c *DeezerClient) GetTrackISRC(ctx context.Context, trackID string) (string
 
 	c.cacheMu.Lock()
 	c.isrcCache[trackID] = fullTrack.ISRC
+	c.maybeCleanupCachesLocked(time.Now())
 	c.cacheMu.Unlock()
 
 	return fullTrack.ISRC, nil
@@ -926,11 +1021,10 @@ func (c *DeezerClient) getBestAlbumImage(album deezerAlbumFull) string {
 }
 
 type AlbumExtendedMetadata struct {
-	Genre string // Comma-separated list of genres
-	Label string // Record label name
+	Genre string
+	Label string
 }
 
-// Uses the album ID from a track to fetch extended metadata
 func (c *DeezerClient) GetAlbumExtendedMetadata(ctx context.Context, albumID string) (*AlbumExtendedMetadata, error) {
 	if albumID == "" {
 		return nil, fmt.Errorf("empty album ID")
@@ -964,10 +1058,12 @@ func (c *DeezerClient) GetAlbumExtendedMetadata(ctx context.Context, albumID str
 	}
 
 	c.cacheMu.Lock()
+	now := time.Now()
 	c.searchCache[cacheKey] = &cacheEntry{
 		data:      result,
-		expiresAt: time.Now().Add(deezerCacheTTL),
+		expiresAt: now.Add(deezerCacheTTL),
 	}
+	c.maybeCleanupCachesLocked(now)
 	c.cacheMu.Unlock()
 
 	GoLog("[Deezer] Album metadata fetched - Genre: %s, Label: %s\n", result.Genre, result.Label)
@@ -975,7 +1071,6 @@ func (c *DeezerClient) GetAlbumExtendedMetadata(ctx context.Context, albumID str
 	return result, nil
 }
 
-// GetTrackAlbumID fetches the album ID for a Deezer track
 func (c *DeezerClient) GetTrackAlbumID(ctx context.Context, trackID string) (string, error) {
 	trackURL := fmt.Sprintf(deezerTrackURL, trackID)
 
@@ -987,7 +1082,6 @@ func (c *DeezerClient) GetTrackAlbumID(ctx context.Context, trackID string) (str
 	return fmt.Sprintf("%d", track.Album.ID), nil
 }
 
-// This is a convenience function that first gets the album ID, then fetches album metadata
 func (c *DeezerClient) GetExtendedMetadataByTrackID(ctx context.Context, trackID string) (*AlbumExtendedMetadata, error) {
 	albumID, err := c.GetTrackAlbumID(ctx, trackID)
 	if err != nil {
@@ -997,30 +1091,62 @@ func (c *DeezerClient) GetExtendedMetadataByTrackID(ctx context.Context, trackID
 	return c.GetAlbumExtendedMetadata(ctx, albumID)
 }
 
-// GetExtendedMetadataByISRC searches for a track by ISRC and fetches extended metadata (genre, label)
 func (c *DeezerClient) GetExtendedMetadataByISRC(ctx context.Context, isrc string) (*AlbumExtendedMetadata, error) {
 	if isrc == "" {
 		return nil, fmt.Errorf("empty ISRC")
 	}
 
-	// First, search for track by ISRC
 	track, err := c.SearchByISRC(ctx, isrc)
 	if err != nil {
 		return nil, fmt.Errorf("failed to find track by ISRC: %w", err)
 	}
 
-	// SpotifyID contains "deezer:123" format, extract the ID
 	deezerID := strings.TrimPrefix(track.SpotifyID, "deezer:")
 
 	if deezerID == "" {
 		return nil, fmt.Errorf("track found but no Deezer ID")
 	}
 
-	// Then fetch extended metadata using the Deezer track ID
 	return c.GetExtendedMetadataByTrackID(ctx, deezerID)
 }
 
 func (c *DeezerClient) getJSON(ctx context.Context, endpoint string, dst interface{}) error {
+	var lastErr error
+
+	for attempt := 0; attempt <= deezerMaxRetries; attempt++ {
+		if attempt > 0 {
+			delay := deezerRetryDelay * time.Duration(1<<(attempt-1)) // Exponential backoff
+			GoLog("[Deezer] Retry %d/%d after %v...\n", attempt, deezerMaxRetries, delay)
+			time.Sleep(delay)
+		}
+
+		err := c.doGetJSON(ctx, endpoint, dst)
+		if err == nil {
+			return nil
+		}
+
+		lastErr = err
+		errStr := err.Error()
+
+		// Check if error is retryable
+		isRetryable := strings.Contains(errStr, "timeout") ||
+			strings.Contains(errStr, "connection reset") ||
+			strings.Contains(errStr, "connection refused") ||
+			strings.Contains(errStr, "EOF") ||
+			strings.Contains(errStr, "status 5") ||
+			strings.Contains(errStr, "status 429")
+
+		if !isRetryable {
+			return err
+		}
+
+		GoLog("[Deezer] Attempt %d failed (retryable): %v\n", attempt+1, err)
+	}
+
+	return fmt.Errorf("all %d attempts failed: %w", deezerMaxRetries+1, lastErr)
+}
+
+func (c *DeezerClient) doGetJSON(ctx context.Context, endpoint string, dst interface{}) error {
 	req, err := http.NewRequestWithContext(ctx, http.MethodGet, endpoint, nil)
 	if err != nil {
 		return err
@@ -1046,7 +1172,6 @@ func (c *DeezerClient) getJSON(ctx context.Context, endpoint string, dst interfa
 	return json.Unmarshal(body, dst)
 }
 
-// parseDeezerURL is internal function, returns type and ID
 func parseDeezerURL(input string) (string, string, error) {
 	trimmed := strings.TrimSpace(input)
 	if trimmed == "" {

go_backend/duplicate.go

@@ -10,7 +10,6 @@ import (
 	"time"
 )
 
-// ISRCIndex holds a cached map of ISRC -> file path for fast duplicate checking
 type ISRCIndex struct {
 	index     map[string]string // ISRC (uppercase) -> file path
 	outputDir string
@@ -25,8 +24,6 @@ var (
 	isrcIndexTTL     = 5 * time.Minute
 )
 
-// GetISRCIndex returns or builds an ISRC index for the given directory
-// Uses per-directory mutex to prevent concurrent builds (race condition fix)
 func GetISRCIndex(outputDir string) *ISRCIndex {
 	// Fast path: check cache first
 	isrcIndexCacheMu.RLock()
@@ -56,7 +53,6 @@ func GetISRCIndex(outputDir string) *ISRCIndex {
 	return buildISRCIndex(outputDir)
 }
 
-// buildISRCIndex scans a directory and builds a map of ISRC -> file path
 func buildISRCIndex(outputDir string) *ISRCIndex {
 	idx := &ISRCIndex{
 		index:     make(map[string]string),
@@ -91,7 +87,7 @@ func buildISRCIndex(outputDir string) *ISRCIndex {
 		return nil
 	})
 
-	fmt.Printf("[ISRCIndex] Built index for %s: %d files in %v\n", 
+	fmt.Printf("[ISRCIndex] Built index for %s: %d files in %v\n",
 		outputDir, fileCount, time.Since(startTime).Round(time.Millisecond))
 
 	isrcIndexCacheMu.Lock()
@@ -113,7 +109,6 @@ func (idx *ISRCIndex) lookup(isrc string) (string, bool) {
 	return path, exists
 }
 
-// remove deletes an ISRC entry from the index (internal use)
 func (idx *ISRCIndex) remove(isrc string) {
 	if isrc == "" {
 		return
@@ -125,14 +120,11 @@ func (idx *ISRCIndex) remove(isrc string) {
 	delete(idx.index, strings.ToUpper(isrc))
 }
 
-// Lookup checks if an ISRC exists in the index (gomobile compatible)
-// Returns filepath if found, empty string if not found
 func (idx *ISRCIndex) Lookup(isrc string) (string, error) {
 	path, _ := idx.lookup(isrc)
 	return path, nil
 }
 
-// Add adds a new ISRC to the index (call after successful download)
 func (idx *ISRCIndex) Add(isrc, filePath string) {
 	if isrc == "" || filePath == "" {
 		return
@@ -144,15 +136,12 @@ func (idx *ISRCIndex) Add(isrc, filePath string) {
 	idx.index[strings.ToUpper(isrc)] = filePath
 }
 
-// InvalidateCache clears the ISRC index cache for a directory
 func InvalidateISRCCache(outputDir string) {
 	isrcIndexCacheMu.Lock()
 	delete(isrcIndexCache, outputDir)
 	isrcIndexCacheMu.Unlock()
 }
 
-// checkISRCExistsInternal checks if a file with the given ISRC exists (internal use)
-// Uses ISRC index for fast lookup
 func checkISRCExistsInternal(outputDir, isrc string) (string, bool) {
 	if isrc == "" || outputDir == "" {
 		return "", false
@@ -173,13 +162,11 @@ func checkISRCExistsInternal(outputDir, isrc string) (string, bool) {
 	return filePath, true
 }
 
-// CheckISRCExists is the exported version for gomobile (returns string, error)
 func CheckISRCExists(outputDir, isrc string) (string, error) {
 	filepath, _ := checkISRCExistsInternal(outputDir, isrc)
 	return filepath, nil
 }
 
-// CheckFileExists checks if a file with the given name exists
 func CheckFileExists(filePath string) bool {
 	info, err := os.Stat(filePath)
 	if err != nil {
@@ -188,7 +175,6 @@ func CheckFileExists(filePath string) bool {
 	return !info.IsDir() && info.Size() > 0
 }
 
-// FileExistenceResult represents the result of checking if a file exists
 type FileExistenceResult struct {
 	ISRC       string `json:"isrc"`
 	Exists     bool   `json:"exists"`
@@ -249,8 +235,6 @@ func CheckFilesExistParallel(outputDir string, tracksJSON string) (string, error
 	return string(resultJSON), nil
 }
 
-// PreBuildISRCIndex pre-builds the ISRC index for a directory
-// Call this when app starts or when entering album/playlist screen
 func PreBuildISRCIndex(outputDir string) error {
 	if outputDir == "" {
 		return fmt.Errorf("output directory is required")
@@ -260,7 +244,6 @@ func PreBuildISRCIndex(outputDir string) error {
 	return nil
 }
 
-// AddToISRCIndex adds a new file to the ISRC index after successful download
 func AddToISRCIndex(outputDir, isrc, filePath string) {
 	if outputDir == "" || isrc == "" || filePath == "" {
 		return

go_backend/extension_manager.go

@@ -47,7 +47,7 @@ type LoadedExtension struct {
 	ID        string             `json:"id"`
 	Manifest  *ExtensionManifest `json:"manifest"`
 	VM        *goja.Runtime      `json:"-"`
-	VMMu      sync.Mutex         `json:"-"` // Mutex to prevent concurrent VM access
+	VMMu      sync.Mutex         `json:"-"`
 	Enabled   bool               `json:"enabled"`
 	Error     string             `json:"error,omitempty"`
 	DataDir   string             `json:"data_dir"`
@@ -55,12 +55,11 @@ type LoadedExtension struct {
 	IconPath  string             `json:"icon_path"`
 }
 
-// ExtensionManager manages all loaded extensions
 type ExtensionManager struct {
 	mu            sync.RWMutex
 	extensions    map[string]*LoadedExtension
-	extensionsDir string // Base directory for extensions
-	dataDir       string // Base directory for extension data
+	extensionsDir string
+	dataDir       string
 }
 
 var (
@@ -99,7 +98,6 @@ func (m *ExtensionManager) LoadExtensionFromFile(filePath string) (*LoadedExtens
 		return nil, fmt.Errorf("Invalid file format. Please select a .spotiflac-ext file")
 	}
 
-	// Open the zip file
 	zipReader, err := zip.OpenReader(filePath)
 	if err != nil {
 		return nil, fmt.Errorf("Cannot open extension file. The file may be corrupted or not a valid extension package")
@@ -222,7 +220,6 @@ func (m *ExtensionManager) LoadExtensionFromFile(filePath string) (*LoadedExtens
 		SourceDir: extDir,
 	}
 
-	// Initialize Goja VM
 	if err := m.initializeVM(ext); err != nil {
 		ext.Error = err.Error()
 		ext.Enabled = false
@@ -269,13 +266,11 @@ func (m *ExtensionManager) initializeVM(ext *LoadedExtension) error {
 		return goja.Undefined()
 	})
 
-	// Run the extension code
 	_, err = vm.RunString(string(jsCode))
 	if err != nil {
 		return fmt.Errorf("failed to execute extension code: %w", err)
 	}
 
-	// Verify extension was registered
 	if registeredExtension == nil || goja.IsUndefined(registeredExtension) {
 		return fmt.Errorf("extension did not call registerExtension()")
 	}
@@ -283,7 +278,6 @@ func (m *ExtensionManager) initializeVM(ext *LoadedExtension) error {
 	return nil
 }
 
-// UnloadExtension unloads an extension by ID
 func (m *ExtensionManager) UnloadExtension(extensionID string) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -293,9 +287,7 @@ func (m *ExtensionManager) UnloadExtension(extensionID string) error {
 		return fmt.Errorf("Extension not found")
 	}
 
-	// Call cleanup if VM is initialized
 	if ext.VM != nil {
-		// Try to call cleanup function
 		cleanup, err := ext.VM.RunString("typeof extension !== 'undefined' && typeof extension.cleanup === 'function' ? extension.cleanup() : null")
 		if err != nil {
 			GoLog("[Extension] Error calling cleanup for %s: %v\n", extensionID, err)
@@ -304,14 +296,12 @@ func (m *ExtensionManager) UnloadExtension(extensionID string) error {
 		}
 	}
 
-	// Remove from registry
 	delete(m.extensions, extensionID)
 	GoLog("[Extension] Unloaded extension: %s\n", extensionID)
 
 	return nil
 }
 
-// Returns error if extension not found (gomobile compatible)
 func (m *ExtensionManager) GetExtension(extensionID string) (*LoadedExtension, error) {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -323,7 +313,6 @@ func (m *ExtensionManager) GetExtension(extensionID string) (*LoadedExtension, e
 	return ext, nil
 }
 
-// GetAllExtensions returns all loaded extensions
 func (m *ExtensionManager) GetAllExtensions() []*LoadedExtension {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -347,7 +336,6 @@ func (m *ExtensionManager) SetExtensionEnabled(extensionID string, enabled bool)
 	ext.Enabled = enabled
 	GoLog("[Extension] %s %s\n", extensionID, map[bool]string{true: "enabled", false: "disabled"}[enabled])
 
-	// Persist enabled state to settings store
 	store := GetExtensionSettingsStore()
 	if err := store.Set(extensionID, "_enabled", enabled); err != nil {
 		GoLog("[Extension] Failed to persist enabled state for %s: %v\n", extensionID, err)
@@ -356,7 +344,6 @@ func (m *ExtensionManager) SetExtensionEnabled(extensionID string, enabled bool)
 	return nil
 }
 
-// LoadExtensionsFromDirectory scans a directory and loads all valid extensions
 func (m *ExtensionManager) LoadExtensionsFromDirectory(dirPath string) ([]string, []error) {
 	var loaded []string
 	var errors []error
@@ -443,7 +430,6 @@ func (m *ExtensionManager) loadExtensionFromDirectory(dirPath string) (*LoadedEx
 		}
 	}
 
-	// Initialize Goja VM
 	if err := m.initializeVM(ext); err != nil {
 		ext.Error = err.Error()
 		ext.Enabled = false
@@ -456,19 +442,16 @@ func (m *ExtensionManager) loadExtensionFromDirectory(dirPath string) (*LoadedEx
 	return ext, nil
 }
 
-// RemoveExtension completely removes an extension (unload + delete files)
 func (m *ExtensionManager) RemoveExtension(extensionID string) error {
 	ext, err := m.GetExtension(extensionID)
 	if err != nil {
 		return err
 	}
 
-	// Unload first
 	if err := m.UnloadExtension(extensionID); err != nil {
 		return err
 	}
 
-	// Remove source directory
 	if ext.SourceDir != "" {
 		if err := os.RemoveAll(ext.SourceDir); err != nil {
 			GoLog("[Extension] Warning: failed to remove source dir: %v\n", err)
@@ -490,7 +473,6 @@ func (m *ExtensionManager) UpgradeExtension(filePath string) (*LoadedExtension,
 		return nil, fmt.Errorf("Invalid file format. Please select a .spotiflac-ext file")
 	}
 
-	// Open the zip file
 	zipReader, err := zip.OpenReader(filePath)
 	if err != nil {
 		return nil, fmt.Errorf("Cannot open extension file. The file may be corrupted or not a valid extension package")
@@ -554,11 +536,9 @@ func (m *ExtensionManager) UpgradeExtension(filePath string) (*LoadedExtension,
 	extDir := existing.SourceDir
 	wasEnabled := existing.Enabled
 
-	// Cleanup and unload existing extension
 	m.CleanupExtension(existing.ID)
 	m.UnloadExtension(existing.ID)
 
-	// Remove old source files but keep data directory
 	if extDir != "" {
 		if err := os.RemoveAll(extDir); err != nil {
 			GoLog("[Extension] Warning: failed to remove old source dir: %v\n", err)
@@ -637,16 +617,14 @@ type ExtensionUpgradeInfo struct {
 	IsInstalled    bool   `json:"is_installed"`
 }
 
-// checkExtensionUpgradeInternal checks if a package file is an upgrade for an existing extension
-// Internal function that returns struct
 func (m *ExtensionManager) checkExtensionUpgradeInternal(filePath string) (*ExtensionUpgradeInfo, error) {
 	// Validate file extension
 	if !strings.HasSuffix(strings.ToLower(filePath), ".spotiflac-ext") {
-		return nil, fmt.Errorf("Invalid file format")
+		return nil, fmt.Errorf("Invalid file format. Please select a .spotiflac-ext file")
 	}
 
-	// Open the zip file
 	zipReader, err := zip.OpenReader(filePath)
+
 	if err != nil {
 		return nil, fmt.Errorf("Cannot open extension file")
 	}
@@ -714,7 +692,6 @@ func (m *ExtensionManager) CheckExtensionUpgradeJSON(filePath string) (string, e
 	return string(jsonBytes), nil
 }
 
-// GetInstalledExtensionsJSON returns all extensions as JSON for Flutter
 func (m *ExtensionManager) GetInstalledExtensionsJSON() (string, error) {
 	extensions := m.GetAllExtensions()
 
@@ -809,8 +786,6 @@ func (m *ExtensionManager) GetInstalledExtensionsJSON() (string, error) {
 	return string(jsonBytes), nil
 }
 
-// ==================== Extension Lifecycle ====================
-
 func (m *ExtensionManager) InitializeExtension(extensionID string, settings map[string]interface{}) error {
 	m.mu.Lock()
 	defer m.mu.Unlock()
@@ -923,7 +898,6 @@ func (m *ExtensionManager) CleanupExtension(extensionID string) error {
 	return nil
 }
 
-// UnloadAllExtensions unloads all extensions gracefully
 func (m *ExtensionManager) UnloadAllExtensions() {
 	m.mu.Lock()
 	extensionIDs := make([]string, 0, len(m.extensions))
@@ -940,7 +914,6 @@ func (m *ExtensionManager) UnloadAllExtensions() {
 	GoLog("[Extension] All extensions unloaded\n")
 }
 
-// The function is called as extension.<actionName>() and can return a result
 func (m *ExtensionManager) InvokeAction(extensionID string, actionName string) (map[string]interface{}, error) {
 	m.mu.Lock()
 	defer m.mu.Unlock()

go_backend/extension_manifest.go

@@ -7,7 +7,6 @@ import (
 	"strings"
 )
 
-// ExtensionType represents the type of extension
 type ExtensionType string
 
 const (
@@ -15,7 +14,6 @@ const (
 	ExtensionTypeDownloadProvider ExtensionType = "download_provider"
 )
 
-// SettingType represents the type of a setting field
 type SettingType string
 
 const (
@@ -26,14 +24,12 @@ const (
 	SettingTypeButton SettingType = "button" // Action button that calls a JS function
 )
 
-// ExtensionPermissions defines what resources an extension can access
 type ExtensionPermissions struct {
-	Network []string `json:"network"` // List of allowed domains
-	Storage bool     `json:"storage"` // Whether extension can use storage API
-	File    bool     `json:"file"`    // Whether extension can use file API
+	Network []string `json:"network"`
+	Storage bool     `json:"storage"`
+	File    bool     `json:"file"`
 }
 
-// ExtensionSetting defines a configurable setting for an extension
 type ExtensionSetting struct {
 	Key         string      `json:"key"`
 	Type        SettingType `json:"type"`
@@ -42,19 +38,17 @@ type ExtensionSetting struct {
 	Required    bool        `json:"required,omitempty"`
 	Secret      bool        `json:"secret,omitempty"`
 	Default     interface{} `json:"default,omitempty"`
-	Options     []string    `json:"options,omitempty"` // For select type
-	Action      string      `json:"action,omitempty"`  // For button type: JS function name to call (e.g., "startLogin")
+	Options     []string    `json:"options,omitempty"`
+	Action      string      `json:"action,omitempty"`
 }
 
-// QualityOption represents a quality option for download providers
 type QualityOption struct {
-	ID          string                   `json:"id"`                 // Unique identifier (e.g., "mp3_320", "opus_128")
-	Label       string                   `json:"label"`              // Display name (e.g., "MP3 320kbps")
-	Description string                   `json:"description"`        // Optional description (e.g., "Best quality MP3")
-	Settings    []QualitySpecificSetting `json:"settings,omitempty"` // Quality-specific settings
+	ID          string                   `json:"id"`
+	Label       string                   `json:"label"`
+	Description string                   `json:"description"`
+	Settings    []QualitySpecificSetting `json:"settings,omitempty"`
 }
 
-// QualitySpecificSetting represents a setting that's specific to a quality option
 type QualitySpecificSetting struct {
 	Key         string      `json:"key"`
 	Type        SettingType `json:"type"`
@@ -63,57 +57,50 @@ type QualitySpecificSetting struct {
 	Required    bool        `json:"required,omitempty"`
 	Secret      bool        `json:"secret,omitempty"`
 	Default     interface{} `json:"default,omitempty"`
-	Options     []string    `json:"options,omitempty"` // For select type
+	Options     []string    `json:"options,omitempty"`
 }
 
-// SearchFilter defines a filter option for search
 type SearchFilter struct {
-	ID    string `json:"id"`              // Filter identifier (e.g., "track", "album", "artist", "playlist")
-	Label string `json:"label,omitempty"` // Display label (e.g., "Songs", "Albums", "Artists", "Playlists")
-	Icon  string `json:"icon,omitempty"`  // Optional icon name
+	ID    string `json:"id"`
+	Label string `json:"label,omitempty"`
+	Icon  string `json:"icon,omitempty"`
 }
 
-// SearchBehaviorConfig defines custom search behavior for an extension
 type SearchBehaviorConfig struct {
-	Enabled         bool           `json:"enabled"`                   // Whether extension provides custom search
-	Placeholder     string         `json:"placeholder,omitempty"`     // Placeholder text for search box
-	Primary         bool           `json:"primary,omitempty"`         // If true, show as primary search tab
-	Icon            string         `json:"icon,omitempty"`            // Icon for search tab
-	ThumbnailRatio  string         `json:"thumbnailRatio,omitempty"`  // Thumbnail aspect ratio: "square" (1:1), "wide" (16:9), "portrait" (2:3)
-	ThumbnailWidth  int            `json:"thumbnailWidth,omitempty"`  // Custom thumbnail width in pixels
-	ThumbnailHeight int            `json:"thumbnailHeight,omitempty"` // Custom thumbnail height in pixels
-	Filters         []SearchFilter `json:"filters,omitempty"`         // Available search filters (e.g., track, album, artist, playlist)
+	Enabled         bool           `json:"enabled"`
+	Placeholder     string         `json:"placeholder,omitempty"`
+	Primary         bool           `json:"primary,omitempty"`
+	Icon            string         `json:"icon,omitempty"`
+	ThumbnailRatio  string         `json:"thumbnailRatio,omitempty"`
+	ThumbnailWidth  int            `json:"thumbnailWidth,omitempty"`
+	ThumbnailHeight int            `json:"thumbnailHeight,omitempty"`
+	Filters         []SearchFilter `json:"filters,omitempty"`
 }
 
-// URLHandlerConfig defines custom URL handling for an extension
 type URLHandlerConfig struct {
-	Enabled  bool     `json:"enabled"`            // Whether extension handles URLs
-	Patterns []string `json:"patterns,omitempty"` // URL patterns to match (e.g., "music.youtube.com", "soundcloud.com")
+	Enabled  bool     `json:"enabled"`
+	Patterns []string `json:"patterns,omitempty"`
 }
 
-// TrackMatchingConfig defines custom track matching behavior
 type TrackMatchingConfig struct {
-	CustomMatching    bool   `json:"customMatching"`              // Whether extension handles matching
-	Strategy          string `json:"strategy,omitempty"`          // "isrc", "name", "duration", "custom"
-	DurationTolerance int    `json:"durationTolerance,omitempty"` // Tolerance in seconds for duration matching
+	CustomMatching    bool   `json:"customMatching"`
+	Strategy          string `json:"strategy,omitempty"`
+	DurationTolerance int    `json:"durationTolerance,omitempty"`
 }
 
-// PostProcessingHook defines a post-processing hook
 type PostProcessingHook struct {
-	ID               string   `json:"id"`                         // Unique identifier
-	Name             string   `json:"name"`                       // Display name
-	Description      string   `json:"description,omitempty"`      // Description
-	DefaultEnabled   bool     `json:"defaultEnabled,omitempty"`   // Whether enabled by default
-	SupportedFormats []string `json:"supportedFormats,omitempty"` // Supported file formats (e.g., ["flac", "mp3"])
+	ID               string   `json:"id"`
+	Name             string   `json:"name"`
+	Description      string   `json:"description,omitempty"`
+	DefaultEnabled   bool     `json:"defaultEnabled,omitempty"`
+	SupportedFormats []string `json:"supportedFormats,omitempty"`
 }
 
-// PostProcessingConfig defines post-processing capabilities
 type PostProcessingConfig struct {
-	Enabled bool                 `json:"enabled"`         // Whether extension provides post-processing
-	Hooks   []PostProcessingHook `json:"hooks,omitempty"` // Available hooks
+	Enabled bool                 `json:"enabled"`
+	Hooks   []PostProcessingHook `json:"hooks,omitempty"`
 }
 
-// ExtensionManifest represents the manifest.json of an extension
 type ExtensionManifest struct {
 	Name                   string                 `json:"name"`
 	DisplayName            string                 `json:"displayName"`
@@ -121,22 +108,21 @@ type ExtensionManifest struct {
 	Author                 string                 `json:"author"`
 	Description            string                 `json:"description"`
 	Homepage               string                 `json:"homepage,omitempty"`
-	Icon                   string                 `json:"icon,omitempty"` // Icon filename (e.g., "icon.png")
+	Icon                   string                 `json:"icon,omitempty"`
 	Types                  []ExtensionType        `json:"type"`
 	Permissions            ExtensionPermissions   `json:"permissions"`
 	Settings               []ExtensionSetting     `json:"settings,omitempty"`
-	QualityOptions         []QualityOption        `json:"qualityOptions,omitempty"` // Custom quality options for download providers
+	QualityOptions         []QualityOption        `json:"qualityOptions,omitempty"`
 	MinAppVersion          string                 `json:"minAppVersion,omitempty"`
-	SkipMetadataEnrichment bool                   `json:"skipMetadataEnrichment,omitempty"` // If true, don't enrich metadata from Deezer/Spotify
-	SkipBuiltInFallback    bool                   `json:"skipBuiltInFallback,omitempty"`    // If true, don't fallback to built-in providers (tidal/qobuz/amazon)
-	SearchBehavior         *SearchBehaviorConfig  `json:"searchBehavior,omitempty"`         // Custom search behavior
-	URLHandler             *URLHandlerConfig      `json:"urlHandler,omitempty"`             // Custom URL handling
-	TrackMatching          *TrackMatchingConfig   `json:"trackMatching,omitempty"`          // Custom track matching
-	PostProcessing         *PostProcessingConfig  `json:"postProcessing,omitempty"`         // Post-processing hooks
-	Capabilities           map[string]interface{} `json:"capabilities,omitempty"`           // Extension capabilities (homeFeed, browseCategories, etc.)
+	SkipMetadataEnrichment bool                   `json:"skipMetadataEnrichment,omitempty"`
+	SkipBuiltInFallback    bool                   `json:"skipBuiltInFallback,omitempty"`
+	SearchBehavior         *SearchBehaviorConfig  `json:"searchBehavior,omitempty"`
+	URLHandler             *URLHandlerConfig      `json:"urlHandler,omitempty"`
+	TrackMatching          *TrackMatchingConfig   `json:"trackMatching,omitempty"`
+	PostProcessing         *PostProcessingConfig  `json:"postProcessing,omitempty"`
+	Capabilities           map[string]interface{} `json:"capabilities,omitempty"`
 }
 
-// ManifestValidationError represents a validation error in the manifest
 type ManifestValidationError struct {
 	Field   string
 	Message string
@@ -146,7 +132,6 @@ func (e *ManifestValidationError) Error() string {
 	return fmt.Sprintf("manifest validation error: %s - %s", e.Field, e.Message)
 }
 
-// ParseManifest parses and validates a manifest from JSON bytes
 func ParseManifest(data []byte) (*ExtensionManifest, error) {
 	var manifest ExtensionManifest
 	if err := json.Unmarshal(data, &manifest); err != nil {
@@ -190,7 +175,6 @@ func (m *ExtensionManifest) Validate() error {
 		}
 	}
 
-	// Validate settings if present
 	for i, setting := range m.Settings {
 		if strings.TrimSpace(setting.Key) == "" {
 			return &ManifestValidationError{
@@ -225,7 +209,6 @@ func (m *ExtensionManifest) Validate() error {
 	return nil
 }
 
-// HasType checks if the extension has a specific type
 func (m *ExtensionManifest) HasType(t ExtensionType) bool {
 	for _, et := range m.Types {
 		if et == t {
@@ -235,17 +218,14 @@ func (m *ExtensionManifest) HasType(t ExtensionType) bool {
 	return false
 }
 
-// IsMetadataProvider returns true if extension provides metadata
 func (m *ExtensionManifest) IsMetadataProvider() bool {
 	return m.HasType(ExtensionTypeMetadataProvider)
 }
 
-// IsDownloadProvider returns true if extension provides downloads
 func (m *ExtensionManifest) IsDownloadProvider() bool {
 	return m.HasType(ExtensionTypeDownloadProvider)
 }
 
-// IsDomainAllowed checks if a domain is in the allowed network permissions
 func (m *ExtensionManifest) IsDomainAllowed(domain string) bool {
 	domain = strings.ToLower(strings.TrimSpace(domain))
 	for _, allowed := range m.Permissions.Network {
@@ -255,7 +235,7 @@ func (m *ExtensionManifest) IsDomainAllowed(domain string) bool {
 		}
 		// Support wildcard subdomains (e.g., *.example.com)
 		if strings.HasPrefix(allowed, "*.") {
-			suffix := allowed[1:] // Remove the *
+			suffix := allowed[1:]
 			if strings.HasSuffix(domain, suffix) {
 				return true
 			}
@@ -264,27 +244,22 @@ func (m *ExtensionManifest) IsDomainAllowed(domain string) bool {
 	return false
 }
 
-// HasCustomSearch returns true if extension provides custom search
 func (m *ExtensionManifest) HasCustomSearch() bool {
 	return m.SearchBehavior != nil && m.SearchBehavior.Enabled
 }
 
-// HasCustomMatching returns true if extension provides custom track matching
 func (m *ExtensionManifest) HasCustomMatching() bool {
 	return m.TrackMatching != nil && m.TrackMatching.CustomMatching
 }
 
-// HasPostProcessing returns true if extension provides post-processing
 func (m *ExtensionManifest) HasPostProcessing() bool {
 	return m.PostProcessing != nil && m.PostProcessing.Enabled
 }
 
-// HasURLHandler returns true if extension handles custom URLs
 func (m *ExtensionManifest) HasURLHandler() bool {
 	return m.URLHandler != nil && m.URLHandler.Enabled && len(m.URLHandler.Patterns) > 0
 }
 
-// MatchesURL checks if a URL matches any of the extension's URL patterns
 func (m *ExtensionManifest) MatchesURL(urlStr string) bool {
 	if !m.HasURLHandler() {
 		return false
@@ -293,7 +268,6 @@ func (m *ExtensionManifest) MatchesURL(urlStr string) bool {
 	urlStr = strings.ToLower(strings.TrimSpace(urlStr))
 	for _, pattern := range m.URLHandler.Patterns {
 		pattern = strings.ToLower(strings.TrimSpace(pattern))
-		// Check if URL contains the pattern (host match)
 		if strings.Contains(urlStr, pattern) {
 			return true
 		}
@@ -301,7 +275,6 @@ func (m *ExtensionManifest) MatchesURL(urlStr string) bool {
 	return false
 }
 
-// GetPostProcessingHooks returns all post-processing hooks
 func (m *ExtensionManifest) GetPostProcessingHooks() []PostProcessingHook {
 	if m.PostProcessing == nil {
 		return nil
@@ -309,7 +282,6 @@ func (m *ExtensionManifest) GetPostProcessingHooks() []PostProcessingHook {
 	return m.PostProcessing.Hooks
 }
 
-// ToJSON serializes the manifest to JSON
 func (m *ExtensionManifest) ToJSON() ([]byte, error) {
 	return json.Marshal(m)
 }

go_backend/extension_providers.go

@@ -25,27 +25,26 @@ type ExtTrackMetadata struct {
 	AlbumArtist string `json:"album_artist,omitempty"`
 	DurationMS  int    `json:"duration_ms"`
 	CoverURL    string `json:"cover_url,omitempty"`
-	Images      string `json:"images,omitempty"` // Alternative field for cover URL (used by some extensions)
+	Images      string `json:"images,omitempty"`
 	ReleaseDate string `json:"release_date,omitempty"`
 	TrackNumber int    `json:"track_number,omitempty"`
 	DiscNumber  int    `json:"disc_number,omitempty"`
 	ISRC        string `json:"isrc,omitempty"`
 	ProviderID  string `json:"provider_id"`
-	ItemType    string `json:"item_type,omitempty"`  // track, album, or playlist - for extension search results
-	AlbumType   string `json:"album_type,omitempty"` // album, single, ep, compilation
-	// Enrichment fields from Odesli/song.link
+	ItemType    string `json:"item_type,omitempty"`
+	AlbumType   string `json:"album_type,omitempty"`
+
 	TidalID       string            `json:"tidal_id,omitempty"`
 	QobuzID       string            `json:"qobuz_id,omitempty"`
 	DeezerID      string            `json:"deezer_id,omitempty"`
 	SpotifyID     string            `json:"spotify_id,omitempty"`
-	ExternalLinks map[string]string `json:"external_links,omitempty"` // service -> URL mapping
-	// Extended metadata from enrichment (can come from Deezer, Spotify, etc.)
-	Label     string `json:"label,omitempty"`     // Record label
-	Copyright string `json:"copyright,omitempty"` // Copyright information
-	Genre     string `json:"genre,omitempty"`     // Music genre(s)
+	ExternalLinks map[string]string `json:"external_links,omitempty"`
+
+	Label     string `json:"label,omitempty"`
+	Copyright string `json:"copyright,omitempty"`
+	Genre     string `json:"genre,omitempty"`
 }
 
-// ResolvedCoverURL returns the cover URL, checking both CoverURL and Images fields
 func (t *ExtTrackMetadata) ResolvedCoverURL() string {
 	if t.CoverURL != "" {
 		return t.CoverURL
@@ -53,7 +52,6 @@ func (t *ExtTrackMetadata) ResolvedCoverURL() string {
 	return t.Images
 }
 
-// ExtAlbumMetadata represents album metadata from an extension
 type ExtAlbumMetadata struct {
 	ID          string             `json:"id"`
 	Name        string             `json:"name"`
@@ -67,34 +65,28 @@ type ExtAlbumMetadata struct {
 	ProviderID  string             `json:"provider_id"`
 }
 
-// ExtArtistMetadata represents artist metadata from an extension
 type ExtArtistMetadata struct {
 	ID          string             `json:"id"`
 	Name        string             `json:"name"`
 	ImageURL    string             `json:"image_url,omitempty"`
-	HeaderImage string             `json:"header_image,omitempty"` // Header image for artist page background
-	Listeners   int                `json:"listeners,omitempty"`    // Monthly listeners
+	HeaderImage string             `json:"header_image,omitempty"`
+	Listeners   int                `json:"listeners,omitempty"`
 	Albums      []ExtAlbumMetadata `json:"albums,omitempty"`
-	TopTracks   []ExtTrackMetadata `json:"top_tracks,omitempty"` // Popular tracks
+	TopTracks   []ExtTrackMetadata `json:"top_tracks,omitempty"`
 	ProviderID  string             `json:"provider_id"`
 }
 
-// ExtSearchResult represents search results from an extension
 type ExtSearchResult struct {
 	Tracks []ExtTrackMetadata `json:"tracks"`
 	Total  int                `json:"total"`
 }
 
-// ==================== Download Types ====================
-
-// ExtAvailabilityResult represents availability check result
 type ExtAvailabilityResult struct {
 	Available bool   `json:"available"`
 	Reason    string `json:"reason,omitempty"`
 	TrackID   string `json:"track_id,omitempty"`
 }
 
-// ExtDownloadURLResult represents download URL info
 type ExtDownloadURLResult struct {
 	URL        string `json:"url"`
 	Format     string `json:"format"`
@@ -102,7 +94,6 @@ type ExtDownloadURLResult struct {
 	SampleRate int    `json:"sample_rate,omitempty"`
 }
 
-// ExtDownloadResult represents download result from an extension
 type ExtDownloadResult struct {
 	Success      bool   `json:"success"`
 	FilePath     string `json:"file_path,omitempty"`
@@ -110,7 +101,7 @@ type ExtDownloadResult struct {
 	SampleRate   int    `json:"sample_rate,omitempty"`
 	ErrorMessage string `json:"error_message,omitempty"`
 	ErrorType    string `json:"error_type,omitempty"`
-	// Metadata returned by extension (optional - if provided, can skip enrichment)
+
 	Title       string `json:"title,omitempty"`
 	Artist      string `json:"artist,omitempty"`
 	Album       string `json:"album,omitempty"`
@@ -122,15 +113,11 @@ type ExtDownloadResult struct {
 	ISRC        string `json:"isrc,omitempty"`
 }
 
-// ==================== Provider Wrapper ====================
-
-// ExtensionProviderWrapper wraps an extension to call its provider methods
 type ExtensionProviderWrapper struct {
 	extension *LoadedExtension
 	vm        *goja.Runtime
 }
 
-// NewExtensionProviderWrapper creates a new provider wrapper
 func NewExtensionProviderWrapper(ext *LoadedExtension) *ExtensionProviderWrapper {
 	return &ExtensionProviderWrapper{
 		extension: ext,
@@ -138,9 +125,6 @@ func NewExtensionProviderWrapper(ext *LoadedExtension) *ExtensionProviderWrapper
 	}
 }
 
-// ==================== Metadata Provider Methods ====================
-
-// SearchTracks searches for tracks using the extension
 func (p *ExtensionProviderWrapper) SearchTracks(query string, limit int) (*ExtSearchResult, error) {
 	if !p.extension.Manifest.IsMetadataProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a metadata provider", p.extension.ID)
@@ -150,11 +134,9 @@ func (p *ExtensionProviderWrapper) SearchTracks(query string, limit int) (*ExtSe
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
-	// Call extension's searchTracks function
 	script := fmt.Sprintf(`
 		(function() {
 			if (typeof extension !== 'undefined' && typeof extension.searchTracks === 'function') {
@@ -176,7 +158,6 @@ func (p *ExtensionProviderWrapper) SearchTracks(query string, limit int) (*ExtSe
 		return nil, fmt.Errorf("searchTracks returned null")
 	}
 
-	// Convert result to Go struct
 	exported := result.Export()
 	jsonBytes, err := json.Marshal(exported)
 	if err != nil {
@@ -185,14 +166,11 @@ func (p *ExtensionProviderWrapper) SearchTracks(query string, limit int) (*ExtSe
 
 	var searchResult ExtSearchResult
 
-	// Try to parse as ExtSearchResult object first
 	if err := json.Unmarshal(jsonBytes, &searchResult); err != nil {
-		// If that fails, try parsing as array of tracks directly
 		var tracks []ExtTrackMetadata
 		if arrErr := json.Unmarshal(jsonBytes, &tracks); arrErr != nil {
 			return nil, fmt.Errorf("failed to parse search result: %w (also tried array: %v)", err, arrErr)
 		}
-		// Wrap array in ExtSearchResult
 		searchResult = ExtSearchResult{
 			Tracks: tracks,
 			Total:  len(tracks),
@@ -206,7 +184,6 @@ func (p *ExtensionProviderWrapper) SearchTracks(query string, limit int) (*ExtSe
 	return &searchResult, nil
 }
 
-// GetTrack gets track details by ID
 func (p *ExtensionProviderWrapper) GetTrack(trackID string) (*ExtTrackMetadata, error) {
 	if !p.extension.Manifest.IsMetadataProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a metadata provider", p.extension.ID)
@@ -216,7 +193,6 @@ func (p *ExtensionProviderWrapper) GetTrack(trackID string) (*ExtTrackMetadata,
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -256,7 +232,6 @@ func (p *ExtensionProviderWrapper) GetTrack(trackID string) (*ExtTrackMetadata,
 	return &track, nil
 }
 
-// GetAlbum gets album details by ID
 func (p *ExtensionProviderWrapper) GetAlbum(albumID string) (*ExtAlbumMetadata, error) {
 	if !p.extension.Manifest.IsMetadataProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a metadata provider", p.extension.ID)
@@ -266,7 +241,6 @@ func (p *ExtensionProviderWrapper) GetAlbum(albumID string) (*ExtAlbumMetadata,
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -309,7 +283,6 @@ func (p *ExtensionProviderWrapper) GetAlbum(albumID string) (*ExtAlbumMetadata,
 	return &album, nil
 }
 
-// GetArtist gets artist details by ID
 func (p *ExtensionProviderWrapper) GetArtist(artistID string) (*ExtArtistMetadata, error) {
 	if !p.extension.Manifest.IsMetadataProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a metadata provider", p.extension.ID)
@@ -319,7 +292,6 @@ func (p *ExtensionProviderWrapper) GetArtist(artistID string) (*ExtArtistMetadat
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -359,27 +331,22 @@ func (p *ExtensionProviderWrapper) GetArtist(artistID string) (*ExtArtistMetadat
 	return &artist, nil
 }
 
-// EnrichTrack enriches track metadata before download (e.g., fetch real ISRC)
-// This is called lazily when download starts, not when playlist/album is loaded
-// Extension should implement enrichTrack(track) function that returns enriched track
 func (p *ExtensionProviderWrapper) EnrichTrack(track *ExtTrackMetadata) (*ExtTrackMetadata, error) {
 	if !p.extension.Manifest.IsMetadataProvider() {
-		return track, nil // Not a metadata provider, return as-is
+		return track, nil
 	}
 
 	if !p.extension.Enabled {
-		return track, nil // Extension disabled, return as-is
+		return track, nil
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
-	// Convert track to JSON for passing to JS
 	trackJSON, err := json.Marshal(track)
 	if err != nil {
 		GoLog("[Extension] EnrichTrack: failed to marshal track: %v\n", err)
-		return track, nil // Return original on error
+		return track, nil
 	}
 
 	script := fmt.Sprintf(`
@@ -399,10 +366,9 @@ func (p *ExtensionProviderWrapper) EnrichTrack(track *ExtTrackMetadata) (*ExtTra
 		} else {
 			GoLog("[Extension] EnrichTrack error for %s: %v\n", p.extension.ID, err)
 		}
-		return track, nil // Return original on error
+		return track, nil
 	}
 
-	// If extension doesn't implement enrichTrack or returns null, return original
 	if result == nil || goja.IsUndefined(result) || goja.IsNull(result) {
 		return track, nil
 	}
@@ -420,18 +386,11 @@ func (p *ExtensionProviderWrapper) EnrichTrack(track *ExtTrackMetadata) (*ExtTra
 		return track, nil
 	}
 
-	// Preserve provider ID
 	enrichedTrack.ProviderID = track.ProviderID
 
-	GoLog("[Extension] EnrichTrack: enriched track from %s (ISRC: %s -> %s)\n",
-		p.extension.ID, track.ISRC, enrichedTrack.ISRC)
-
 	return &enrichedTrack, nil
 }
 
-// ==================== Download Provider Methods ====================
-
-// CheckAvailability checks if a track is available for download
 func (p *ExtensionProviderWrapper) CheckAvailability(isrc, trackName, artistName string) (*ExtAvailabilityResult, error) {
 	if !p.extension.Manifest.IsDownloadProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a download provider", p.extension.ID)
@@ -441,7 +400,6 @@ func (p *ExtensionProviderWrapper) CheckAvailability(isrc, trackName, artistName
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -480,7 +438,6 @@ func (p *ExtensionProviderWrapper) CheckAvailability(isrc, trackName, artistName
 	return &availability, nil
 }
 
-// GetDownloadURL gets the download URL for a track
 func (p *ExtensionProviderWrapper) GetDownloadURL(trackID, quality string) (*ExtDownloadURLResult, error) {
 	if !p.extension.Manifest.IsDownloadProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a download provider", p.extension.ID)
@@ -490,7 +447,6 @@ func (p *ExtensionProviderWrapper) GetDownloadURL(trackID, quality string) (*Ext
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -529,10 +485,8 @@ func (p *ExtensionProviderWrapper) GetDownloadURL(trackID, quality string) (*Ext
 	return &urlResult, nil
 }
 
-// ExtDownloadTimeout is longer for extension download operations (5 minutes)
 const ExtDownloadTimeout = 5 * time.Minute
 
-// Download downloads a track with progress reporting
 func (p *ExtensionProviderWrapper) Download(trackID, quality, outputPath string, onProgress func(percent int)) (*ExtDownloadResult, error) {
 	if !p.extension.Manifest.IsDownloadProvider() {
 		return nil, fmt.Errorf("extension '%s' is not a download provider", p.extension.ID)
@@ -542,15 +496,12 @@ func (p *ExtensionProviderWrapper) Download(trackID, quality, outputPath string,
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
-	// Set up progress callback in VM
 	p.vm.Set("__onProgress", func(call goja.FunctionCall) goja.Value {
 		if len(call.Arguments) > 0 {
 			percent := int(call.Arguments[0].ToInteger())
-			// Clamp to 0-100
 			if percent < 0 {
 				percent = 0
 			}
@@ -573,7 +524,6 @@ func (p *ExtensionProviderWrapper) Download(trackID, quality, outputPath string,
 		})()
 	`, trackID, quality, outputPath)
 
-	// Use longer timeout for downloads (5 minutes)
 	result, err := RunWithTimeoutAndRecover(p.vm, script, ExtDownloadTimeout)
 	if err != nil {
 		errMsg := err.Error()
@@ -619,9 +569,6 @@ func (p *ExtensionProviderWrapper) Download(trackID, quality, outputPath string,
 	return &downloadResult, nil
 }
 
-// ==================== Extension Manager Provider Methods ====================
-
-// GetMetadataProviders returns all enabled metadata provider extensions
 func (m *ExtensionManager) GetMetadataProviders() []*ExtensionProviderWrapper {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -635,7 +582,6 @@ func (m *ExtensionManager) GetMetadataProviders() []*ExtensionProviderWrapper {
 	return providers
 }
 
-// GetDownloadProviders returns all enabled download provider extensions
 func (m *ExtensionManager) GetDownloadProviders() []*ExtensionProviderWrapper {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -649,7 +595,6 @@ func (m *ExtensionManager) GetDownloadProviders() []*ExtensionProviderWrapper {
 	return providers
 }
 
-// SearchTracksWithExtensions searches all metadata providers
 func (m *ExtensionManager) SearchTracksWithExtensions(query string, limit int) ([]ExtTrackMetadata, error) {
 	providers := m.GetMetadataProviders()
 	if len(providers) == 0 {
@@ -671,18 +616,12 @@ func (m *ExtensionManager) SearchTracksWithExtensions(query string, limit int) (
 	return allTracks, nil
 }
 
-// ==================== Provider Priority ====================
-
-// providerPriority stores the order of download providers
 var providerPriority []string
 var providerPriorityMu sync.RWMutex
 
-// metadataProviderPriority stores the order of metadata providers
 var metadataProviderPriority []string
 var metadataProviderPriorityMu sync.RWMutex
 
-// SetProviderPriority sets the order of download providers
-// providerIDs should include both built-in ("tidal", "qobuz", "amazon") and extension IDs
 func SetProviderPriority(providerIDs []string) {
 	providerPriorityMu.Lock()
 	defer providerPriorityMu.Unlock()
@@ -690,13 +629,11 @@ func SetProviderPriority(providerIDs []string) {
 	GoLog("[Extension] Download provider priority set: %v\n", providerIDs)
 }
 
-// GetProviderPriority returns the current provider priority order
 func GetProviderPriority() []string {
 	providerPriorityMu.RLock()
 	defer providerPriorityMu.RUnlock()
 
 	if len(providerPriority) == 0 {
-		// Default order: built-in providers first
 		return []string{"tidal", "qobuz", "amazon"}
 	}
 
@@ -705,8 +642,6 @@ func GetProviderPriority() []string {
 	return result
 }
 
-// SetMetadataProviderPriority sets the order of metadata providers
-// providerIDs should include both built-in ("spotify", "deezer") and extension IDs
 func SetMetadataProviderPriority(providerIDs []string) {
 	metadataProviderPriorityMu.Lock()
 	defer metadataProviderPriorityMu.Unlock()
@@ -714,13 +649,11 @@ func SetMetadataProviderPriority(providerIDs []string) {
 	GoLog("[Extension] Metadata provider priority set: %v\n", providerIDs)
 }
 
-// GetMetadataProviderPriority returns the current metadata provider priority order
 func GetMetadataProviderPriority() []string {
 	metadataProviderPriorityMu.RLock()
 	defer metadataProviderPriorityMu.RUnlock()
 
 	if len(metadataProviderPriority) == 0 {
-		// Default order: built-in providers first
 		return []string{"deezer", "spotify"}
 	}
 
@@ -729,30 +662,34 @@ func GetMetadataProviderPriority() []string {
 	return result
 }
 
-// isBuiltInProvider checks if a provider ID is a built-in provider
 func isBuiltInProvider(providerID string) bool {
 	switch providerID {
-	case "tidal", "qobuz", "amazon":
+	case "tidal", "qobuz", "amazon", "deezer":
 		return true
 	default:
 		return false
 	}
 }
 
-// ==================== Download with Fallback ====================
-
-// DownloadWithExtensionFallback tries to download from providers in priority order
-// Includes both built-in providers and extension providers
-// If req.Source is set (extension ID), that extension is tried first
 func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, error) {
 	priority := GetProviderPriority()
 	extManager := GetExtensionManager()
 
-	var lastErr error
-	var skipBuiltIn bool // If source extension has skipBuiltInFallback, don't try built-in providers
+	if req.Service != "" && isBuiltInProvider(req.Service) {
+		GoLog("[DownloadWithExtensionFallback] User selected service: %s, prioritizing it first\n", req.Service)
+		newPriority := []string{req.Service}
+		for _, p := range priority {
+			if p != req.Service {
+				newPriority = append(newPriority, p)
+			}
+		}
+		priority = newPriority
+		GoLog("[DownloadWithExtensionFallback] New priority order: %v\n", priority)
+	}
+
+	var lastErr error
+	var skipBuiltIn bool
 
-	// LAZY ENRICHMENT: If track came from an extension, try to enrich metadata (e.g., get real ISRC)
-	// This is done lazily at download time, not when playlist/album is loaded
 	if req.Source != "" && !isBuiltInProvider(req.Source) {
 		ext, err := extManager.GetExtension(req.Source)
 		if err == nil && ext.Enabled && ext.Error == "" && ext.Manifest.IsMetadataProvider() {
@@ -796,7 +733,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 				if enrichedTrack.Artists != "" {
 					req.ArtistName = enrichedTrack.Artists
 				}
-				// Copy extended metadata from enrichment (label, copyright, genre, release_date)
 				if enrichedTrack.Label != "" && req.Label == "" {
 					GoLog("[DownloadWithExtensionFallback] Label from enrichment: %s\n", enrichedTrack.Label)
 					req.Label = enrichedTrack.Label
@@ -817,7 +753,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 		}
 	}
 
-	// If source extension is specified, try it first before the priority list
 	if req.Source != "" && !isBuiltInProvider(req.Source) {
 		GoLog("[DownloadWithExtensionFallback] Track source is extension '%s', trying it first\n", req.Source)
 
@@ -827,15 +762,12 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 
 			provider := NewExtensionProviderWrapper(ext)
 
-			// For tracks from extension search, use the track ID directly (e.g., "youtube:VIDEO_ID")
-			// The extension already knows how to handle this ID
-			trackID := req.SpotifyID // This contains the extension's track ID (e.g., "youtube:xxx")
+			trackID := req.SpotifyID
 
 			GoLog("[DownloadWithExtensionFallback] Downloading from source extension with trackID: %s (skipBuiltInFallback: %v)\n", trackID, skipBuiltIn)
 
 			outputPath := buildOutputPath(req)
 
-			// Download directly using the track ID from the extension
 			result, err := provider.Download(trackID, req.Quality, outputPath, func(percent int) {
 				if req.ItemID != "" {
 					SetItemProgress(req.ItemID, float64(percent), 0, 0)
@@ -855,7 +787,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					Copyright:        req.Copyright,
 				}
 
-				// Embed genre and label if provided (from Deezer metadata)
 				if req.Genre != "" || req.Label != "" {
 					if err := EmbedGenreLabel(result.FilePath, req.Genre, req.Label); err != nil {
 						GoLog("[DownloadWithExtensionFallback] Warning: failed to embed genre/label: %v\n", err)
@@ -864,7 +795,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					}
 				}
 
-				// If extension has skipMetadataEnrichment, copy metadata
 				if ext.Manifest.SkipMetadataEnrichment {
 					resp.SkipMetadataEnrichment = true
 					if result.Title != "" {
@@ -914,12 +844,11 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 			}
 			GoLog("[DownloadWithExtensionFallback] Source extension %s failed: %v\n", req.Source, lastErr)
 
-			// If skipBuiltInFallback is true, don't continue to other providers
 			if skipBuiltIn {
 				GoLog("[DownloadWithExtensionFallback] skipBuiltInFallback is true, not trying other providers\n")
 				return &DownloadResponse{
 					Success:   false,
-					Error:     fmt.Sprintf("Download failed: %v", lastErr),
+					Error:     "Download failed: " + lastErr.Error(),
 					ErrorType: "extension_error",
 					Service:   req.Source,
 				}, nil
@@ -929,14 +858,11 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 		}
 	}
 
-	// Continue with priority list
 	for _, providerID := range priority {
-		// Skip if we already tried this as source
 		if providerID == req.Source {
 			continue
 		}
 
-		// Skip built-in providers if skipBuiltIn is set
 		if skipBuiltIn && isBuiltInProvider(providerID) {
 			GoLog("[DownloadWithExtensionFallback] Skipping built-in provider %s (skipBuiltInFallback)\n", providerID)
 			continue
@@ -945,7 +871,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 		GoLog("[DownloadWithExtensionFallback] Trying provider: %s\n", providerID)
 
 		if isBuiltInProvider(providerID) {
-			// For built-in providers, enrich with Deezer metadata if not already present
 			if (req.Genre == "" || req.Label == "") && req.ISRC != "" {
 				GoLog("[DownloadWithExtensionFallback] Enriching extended metadata from Deezer for ISRC: %s\n", req.ISRC)
 				ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
@@ -966,11 +891,9 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 				}
 			}
 
-			// Use built-in provider
 			result, err := tryBuiltInProvider(providerID, req)
 			if err == nil && result.Success {
 				result.Service = providerID
-				// Copy enriched metadata to response for Flutter (needed for M4A->FLAC conversion)
 				if req.Label != "" {
 					result.Label = req.Label
 				}
@@ -998,7 +921,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 				GoLog("[DownloadWithExtensionFallback] %s failed: %v\n", providerID, err)
 			}
 		} else {
-			// Try extension provider
 			ext, err := extManager.GetExtension(providerID)
 			if err != nil || !ext.Enabled || ext.Error != "" {
 				GoLog("[DownloadWithExtensionFallback] Extension %s not available\n", providerID)
@@ -1041,7 +963,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					Copyright:        req.Copyright,
 				}
 
-				// Embed genre and label if provided (from Deezer metadata)
 				if req.Genre != "" || req.Label != "" {
 					if err := EmbedGenreLabel(result.FilePath, req.Genre, req.Label); err != nil {
 						GoLog("[DownloadWithExtensionFallback] Warning: failed to embed genre/label: %v\n", err)
@@ -1050,10 +971,8 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 					}
 				}
 
-				// If extension has skipMetadataEnrichment and returned metadata, use it
 				if ext.Manifest.SkipMetadataEnrichment {
 					resp.SkipMetadataEnrichment = true
-					// Copy metadata from extension result if provided
 					if result.Title != "" {
 						resp.Title = result.Title
 					}
@@ -1106,7 +1025,7 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 	if lastErr != nil {
 		return &DownloadResponse{
 			Success:   false,
-			Error:     fmt.Sprintf("All providers failed. Last error: %v", lastErr),
+			Error:     "All providers failed. Last error: " + lastErr.Error(),
 			ErrorType: "not_found",
 		}, nil
 	}
@@ -1118,7 +1037,6 @@ func DownloadWithExtensionFallback(req DownloadRequest) (*DownloadResponse, erro
 	}, nil
 }
 
-// tryBuiltInProvider attempts download from a built-in provider
 func tryBuiltInProvider(providerID string, req DownloadRequest) (*DownloadResponse, error) {
 	req.Service = providerID
 
@@ -1164,16 +1082,18 @@ func tryBuiltInProvider(providerID string, req DownloadRequest) (*DownloadRespon
 		amazonResult, amazonErr := downloadFromAmazon(req)
 		if amazonErr == nil {
 			result = DownloadResult{
-				FilePath:    amazonResult.FilePath,
-				BitDepth:    amazonResult.BitDepth,
-				SampleRate:  amazonResult.SampleRate,
-				Title:       amazonResult.Title,
-				Artist:      amazonResult.Artist,
-				Album:       amazonResult.Album,
-				ReleaseDate: amazonResult.ReleaseDate,
-				TrackNumber: amazonResult.TrackNumber,
-				DiscNumber:  amazonResult.DiscNumber,
-				ISRC:        amazonResult.ISRC,
+				FilePath:      amazonResult.FilePath,
+				BitDepth:      amazonResult.BitDepth,
+				SampleRate:    amazonResult.SampleRate,
+				Title:         amazonResult.Title,
+				Artist:        amazonResult.Artist,
+				Album:         amazonResult.Album,
+				ReleaseDate:   amazonResult.ReleaseDate,
+				TrackNumber:   amazonResult.TrackNumber,
+				DiscNumber:    amazonResult.DiscNumber,
+				ISRC:          amazonResult.ISRC,
+				LyricsLRC:     amazonResult.LyricsLRC,
+				DecryptionKey: amazonResult.DecryptionKey,
 			}
 		}
 		err = amazonErr
@@ -1201,18 +1121,28 @@ func tryBuiltInProvider(providerID string, req DownloadRequest) (*DownloadRespon
 		Genre:            req.Genre,
 		Label:            req.Label,
 		Copyright:        req.Copyright,
+		LyricsLRC:        result.LyricsLRC,
+		DecryptionKey:    result.DecryptionKey,
 	}, nil
 }
 
-// buildOutputPath builds the output file path from request
 func buildOutputPath(req DownloadRequest) string {
+	if strings.TrimSpace(req.OutputPath) != "" {
+		return strings.TrimSpace(req.OutputPath)
+	}
+
 	metadata := map[string]interface{}{
 		"title":        req.TrackName,
 		"artist":       req.ArtistName,
 		"album":        req.AlbumName,
 		"album_artist": req.AlbumArtist,
+		"track":        req.TrackNumber,
 		"track_number": req.TrackNumber,
+		"disc":         req.DiscNumber,
 		"disc_number":  req.DiscNumber,
+		"year":         extractYear(req.ReleaseDate),
+		"date":         req.ReleaseDate,
+		"release_date": req.ReleaseDate,
 		"isrc":         req.ISRC,
 	}
 
@@ -1221,12 +1151,16 @@ func buildOutputPath(req DownloadRequest) string {
 		filename = sanitizeFilename(fmt.Sprintf("%s - %s", req.ArtistName, req.TrackName))
 	}
 
-	return fmt.Sprintf("%s/%s.flac", req.OutputDir, filename)
+	ext := strings.TrimSpace(req.OutputExt)
+	if ext == "" {
+		ext = ".flac"
+	} else if !strings.HasPrefix(ext, ".") {
+		ext = "." + ext
+	}
+
+	return fmt.Sprintf("%s/%s%s", req.OutputDir, filename, ext)
 }
 
-// ==================== Custom Search ====================
-
-// CustomSearch performs a custom search using an extension's search function
 func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string]interface{}) ([]ExtTrackMetadata, error) {
 	if !p.extension.Manifest.HasCustomSearch() {
 		return nil, fmt.Errorf("extension '%s' does not support custom search", p.extension.ID)
@@ -1236,21 +1170,33 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
-	// Convert options to JSON
-	optionsJSON, _ := json.Marshal(options)
+	if options == nil {
+		options = map[string]interface{}{}
+	}
 
-	script := fmt.Sprintf(`
+	// Avoid embedding user input directly into JS source. Some inputs can trigger
+	// parser/runtime edge cases on specific devices/Goja builds.
+	const queryVar = "__sf_custom_search_query"
+	const optionsVar = "__sf_custom_search_options"
+	global := p.vm.GlobalObject()
+	_ = global.Set(queryVar, query)
+	_ = global.Set(optionsVar, options)
+	defer func() {
+		global.Delete(queryVar)
+		global.Delete(optionsVar)
+	}()
+
+	const script = `
 		(function() {
 			if (typeof extension !== 'undefined' && typeof extension.customSearch === 'function') {
-				return extension.customSearch(%q, %s);
+				return extension.customSearch(__sf_custom_search_query, __sf_custom_search_options);
 			}
 			return null;
 		})()
-	`, query, string(optionsJSON))
+	`
 
 	result, err := RunWithTimeoutAndRecover(p.vm, script, DefaultJSTimeout)
 	if err != nil {
@@ -1261,7 +1207,6 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 	}
 
 	if result == nil || goja.IsUndefined(result) || goja.IsNull(result) {
-		// Return empty array instead of error for no results
 		return []ExtTrackMetadata{}, nil
 	}
 
@@ -1276,7 +1221,6 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 		return nil, fmt.Errorf("failed to parse search result: %w", err)
 	}
 
-	// Return empty array if no tracks found
 	if tracks == nil {
 		tracks = []ExtTrackMetadata{}
 	}
@@ -1288,20 +1232,16 @@ func (p *ExtensionProviderWrapper) CustomSearch(query string, options map[string
 	return tracks, nil
 }
 
-// ==================== Custom URL Handler ====================
-
-// ExtURLHandleResult represents the result of URL handling
 type ExtURLHandleResult struct {
-	Type     string             `json:"type"`                // "track", "album", "playlist", "artist"
-	Track    *ExtTrackMetadata  `json:"track,omitempty"`     // For single track
-	Tracks   []ExtTrackMetadata `json:"tracks,omitempty"`    // For album/playlist
-	Album    *ExtAlbumMetadata  `json:"album,omitempty"`     // Album info
-	Artist   *ExtArtistMetadata `json:"artist,omitempty"`    // Artist info
-	Name     string             `json:"name,omitempty"`      // Playlist/album name
-	CoverURL string             `json:"cover_url,omitempty"` // Cover image
+	Type     string             `json:"type"`
+	Track    *ExtTrackMetadata  `json:"track,omitempty"`
+	Tracks   []ExtTrackMetadata `json:"tracks,omitempty"`
+	Album    *ExtAlbumMetadata  `json:"album,omitempty"`
+	Artist   *ExtArtistMetadata `json:"artist,omitempty"`
+	Name     string             `json:"name,omitempty"`
+	CoverURL string             `json:"cover_url,omitempty"`
 }
 
-// HandleURL processes a URL using the extension's URL handler
 func (p *ExtensionProviderWrapper) HandleURL(url string) (*ExtURLHandleResult, error) {
 	if !p.extension.Manifest.HasURLHandler() {
 		return nil, fmt.Errorf("extension '%s' does not support URL handling", p.extension.ID)
@@ -1311,7 +1251,6 @@ func (p *ExtensionProviderWrapper) HandleURL(url string) (*ExtURLHandleResult, e
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -1347,7 +1286,6 @@ func (p *ExtensionProviderWrapper) HandleURL(url string) (*ExtURLHandleResult, e
 		return nil, fmt.Errorf("failed to parse URL handle result: %w", err)
 	}
 
-	// Set provider ID on tracks
 	if handleResult.Track != nil {
 		handleResult.Track.ProviderID = p.extension.ID
 	}
@@ -1376,9 +1314,6 @@ func (p *ExtensionProviderWrapper) HandleURL(url string) (*ExtURLHandleResult, e
 	return &handleResult, nil
 }
 
-// ==================== Custom Track Matching ====================
-
-// MatchTrackResult represents the result of custom track matching
 type MatchTrackResult struct {
 	Matched    bool    `json:"matched"`
 	TrackID    string  `json:"track_id,omitempty"`
@@ -1386,7 +1321,6 @@ type MatchTrackResult struct {
 	Reason     string  `json:"reason,omitempty"`
 }
 
-// MatchTrack uses extension's custom matching algorithm
 func (p *ExtensionProviderWrapper) MatchTrack(sourceTrack map[string]interface{}, candidates []map[string]interface{}) (*MatchTrackResult, error) {
 	if !p.extension.Manifest.HasCustomMatching() {
 		return nil, fmt.Errorf("extension '%s' does not support custom matching", p.extension.ID)
@@ -1396,7 +1330,6 @@ func (p *ExtensionProviderWrapper) MatchTrack(sourceTrack map[string]interface{}
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -1438,22 +1371,26 @@ func (p *ExtensionProviderWrapper) MatchTrack(sourceTrack map[string]interface{}
 	return &matchResult, nil
 }
 
-// ==================== Post-Processing ====================
-
-// PostProcessResult represents the result of post-processing
 type PostProcessResult struct {
 	Success     bool   `json:"success"`
 	NewFilePath string `json:"new_file_path,omitempty"`
+	NewFileURI  string `json:"new_file_uri,omitempty"`
 	Error       string `json:"error,omitempty"`
-	// Additional metadata that may have changed
-	BitDepth   int `json:"bit_depth,omitempty"`
-	SampleRate int `json:"sample_rate,omitempty"`
+	BitDepth    int    `json:"bit_depth,omitempty"`
+	SampleRate  int    `json:"sample_rate,omitempty"`
+}
+
+type PostProcessInput struct {
+	Path     string `json:"path,omitempty"`
+	URI      string `json:"uri,omitempty"`
+	Name     string `json:"name,omitempty"`
+	MimeType string `json:"mime_type,omitempty"`
+	Size     int64  `json:"size,omitempty"`
+	IsSAF    bool   `json:"is_saf,omitempty"`
 }
 
-// PostProcessTimeout is longer for post-processing (2 minutes)
 const PostProcessTimeout = 2 * time.Minute
 
-// PostProcess runs post-processing hooks on a downloaded file
 func (p *ExtensionProviderWrapper) PostProcess(filePath string, metadata map[string]interface{}, hookID string) (*PostProcessResult, error) {
 	if !p.extension.Manifest.HasPostProcessing() {
 		return nil, fmt.Errorf("extension '%s' does not support post-processing", p.extension.ID)
@@ -1463,7 +1400,6 @@ func (p *ExtensionProviderWrapper) PostProcess(filePath string, metadata map[str
 		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
 	}
 
-	// Lock VM to prevent concurrent access
 	p.extension.VMMu.Lock()
 	defer p.extension.VMMu.Unlock()
 
@@ -1517,9 +1453,75 @@ func (p *ExtensionProviderWrapper) PostProcess(filePath string, metadata map[str
 	return &postResult, nil
 }
 
-// ==================== Extension Manager Advanced Methods ====================
+func (p *ExtensionProviderWrapper) PostProcessV2(input PostProcessInput, metadata map[string]interface{}, hookID string) (*PostProcessResult, error) {
+	if !p.extension.Manifest.HasPostProcessing() {
+		return nil, fmt.Errorf("extension '%s' does not support post-processing", p.extension.ID)
+	}
+
+	if !p.extension.Enabled {
+		return nil, fmt.Errorf("extension '%s' is disabled", p.extension.ID)
+	}
+
+	p.extension.VMMu.Lock()
+	defer p.extension.VMMu.Unlock()
+
+	metadataJSON, _ := json.Marshal(metadata)
+	inputJSON, _ := json.Marshal(input)
+	filePath := input.Path
+
+	script := fmt.Sprintf(`
+		(function() {
+			if (typeof extension !== 'undefined') {
+				if (typeof extension.postProcessV2 === 'function') {
+					return extension.postProcessV2(%s, %s, %q);
+				}
+				if (typeof extension.postProcess === 'function') {
+					return extension.postProcess(%q, %s, %q);
+				}
+			}
+			return null;
+		})()
+	`, string(inputJSON), string(metadataJSON), hookID, filePath, string(metadataJSON), hookID)
+
+	result, err := RunWithTimeoutAndRecover(p.vm, script, PostProcessTimeout)
+	if err != nil {
+		errMsg := err.Error()
+		if IsTimeoutError(err) {
+			errMsg = "postProcess timeout: extension took too long to complete"
+		}
+		return &PostProcessResult{
+			Success: false,
+			Error:   errMsg,
+		}, nil
+	}
+
+	if result == nil || goja.IsUndefined(result) || goja.IsNull(result) {
+		return &PostProcessResult{
+			Success: false,
+			Error:   "postProcess returned null",
+		}, nil
+	}
+
+	exported := result.Export()
+	jsonBytes, err := json.Marshal(exported)
+	if err != nil {
+		return &PostProcessResult{
+			Success: false,
+			Error:   fmt.Sprintf("failed to marshal result: %v", err),
+		}, nil
+	}
+
+	var postResult PostProcessResult
+	if err := json.Unmarshal(jsonBytes, &postResult); err != nil {
+		return &PostProcessResult{
+			Success: false,
+			Error:   fmt.Sprintf("failed to parse result: %v", err),
+		}, nil
+	}
+
+	return &postResult, nil
+}
 
-// GetSearchProviders returns all extensions that provide custom search
 func (m *ExtensionManager) GetSearchProviders() []*ExtensionProviderWrapper {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -1533,7 +1535,6 @@ func (m *ExtensionManager) GetSearchProviders() []*ExtensionProviderWrapper {
 	return providers
 }
 
-// GetURLHandlers returns all extensions that handle custom URLs
 func (m *ExtensionManager) GetURLHandlers() []*ExtensionProviderWrapper {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -1547,7 +1548,6 @@ func (m *ExtensionManager) GetURLHandlers() []*ExtensionProviderWrapper {
 	return providers
 }
 
-// FindURLHandler finds an extension that can handle the given URL
 func (m *ExtensionManager) FindURLHandler(url string) *ExtensionProviderWrapper {
 	m.mu.RLock()
 	defer m.mu.RUnlock()
@@ -1560,14 +1560,11 @@ func (m *ExtensionManager) FindURLHandler(url string) *ExtensionProviderWrapper
 	return nil
 }
 
-// ExtURLHandleResultWithExtID wraps ExtURLHandleResult with extension ID for gomobile compatibility
 type ExtURLHandleResultWithExtID struct {
 	Result      *ExtURLHandleResult
 	ExtensionID string
 }
 
-// HandleURLWithExtension tries to handle a URL with any matching extension
-// Returns result with extension ID, or error if no handler found
 func (m *ExtensionManager) HandleURLWithExtension(url string) (*ExtURLHandleResultWithExtID, error) {
 	handler := m.FindURLHandler(url)
 	if handler == nil {
@@ -1647,3 +1644,58 @@ func (m *ExtensionManager) RunPostProcessing(filePath string, metadata map[strin
 
 	return &PostProcessResult{Success: true, NewFilePath: currentPath}, nil
 }
+
+// RunPostProcessingV2 runs all enabled post-processing hooks on a file input.
+func (m *ExtensionManager) RunPostProcessingV2(input PostProcessInput, metadata map[string]interface{}) (*PostProcessResult, error) {
+	providers := m.GetPostProcessingProviders()
+	if len(providers) == 0 {
+		return &PostProcessResult{Success: true, NewFilePath: input.Path, NewFileURI: input.URI}, nil
+	}
+
+	currentInput := input
+	for _, provider := range providers {
+		hooks := provider.extension.Manifest.GetPostProcessingHooks()
+		for _, hook := range hooks {
+			if !hook.DefaultEnabled {
+				continue
+			}
+
+			ext := strings.ToLower(filepath.Ext(currentInput.Path))
+			if ext == "" && currentInput.Name != "" {
+				ext = strings.ToLower(filepath.Ext(currentInput.Name))
+			}
+			if len(hook.SupportedFormats) > 0 && ext != "" {
+				supported := false
+				for _, format := range hook.SupportedFormats {
+					if "."+format == ext || format == ext[1:] {
+						supported = true
+						break
+					}
+				}
+				if !supported {
+					continue
+				}
+			}
+
+			GoLog("[PostProcessV2] Running hook %s from %s on %s\n", hook.ID, provider.extension.ID, currentInput.Path)
+
+			result, err := provider.PostProcessV2(currentInput, metadata, hook.ID)
+			if err != nil {
+				GoLog("[PostProcessV2] Hook %s failed: %v\n", hook.ID, err)
+				continue
+			}
+
+			if result.Success && result.NewFilePath != "" {
+				currentInput.Path = result.NewFilePath
+				if currentInput.Name == "" {
+					currentInput.Name = filepath.Base(result.NewFilePath)
+				}
+			}
+			if result.Success && result.NewFileURI != "" {
+				currentInput.URI = result.NewFileURI
+			}
+		}
+	}
+
+	return &PostProcessResult{Success: true, NewFilePath: currentInput.Path, NewFileURI: currentInput.URI}, nil
+}

go_backend/extension_runtime.go

@@ -1,8 +1,11 @@
 package gobackend
 
 import (
+	"fmt"
+	"net"
 	"net/http"
 	"net/url"
+	"strings"
 	"sync"
 	"time"
 
@@ -23,9 +26,8 @@ type ExtensionAuthState struct {
 	RefreshToken    string
 	ExpiresAt       time.Time
 	IsAuthenticated bool
-	// PKCE support
-	PKCEVerifier  string
-	PKCEChallenge string
+	PKCEVerifier    string
+	PKCEChallenge   string
 }
 
 type PendingAuthRequest struct {
@@ -39,7 +41,6 @@ var (
 	pendingAuthRequestsMu sync.RWMutex
 )
 
-// GetPendingAuthRequest returns pending auth request for an extension (called from Flutter)
 func GetPendingAuthRequest(extensionID string) *PendingAuthRequest {
 	pendingAuthRequestsMu.RLock()
 	defer pendingAuthRequestsMu.RUnlock()
@@ -105,8 +106,16 @@ func NewExtensionRuntime(ext *LoadedExtension) *ExtensionRuntime {
 		Timeout: 30 * time.Second,
 		Jar:     jar,
 		CheckRedirect: func(req *http.Request, via []*http.Request) error {
-			// Validate redirect target domain against allowed domains
+			if req.URL.Scheme != "https" {
+				GoLog("[Extension:%s] Redirect blocked: non-https scheme '%s'\n", ext.ID, req.URL.Scheme)
+				return fmt.Errorf("redirect blocked: only https is allowed")
+			}
+
 			domain := req.URL.Hostname()
+			if domain == "" {
+				GoLog("[Extension:%s] Redirect blocked: missing hostname\n", ext.ID)
+				return fmt.Errorf("redirect blocked: hostname is required")
+			}
 			if !ext.Manifest.IsDomainAllowed(domain) {
 				GoLog("[Extension:%s] Redirect blocked: domain '%s' not in allowed list\n", ext.ID, domain)
 				return &RedirectBlockedError{Domain: domain}
@@ -115,7 +124,6 @@ func NewExtensionRuntime(ext *LoadedExtension) *ExtensionRuntime {
 				GoLog("[Extension:%s] Redirect blocked: private IP '%s'\n", ext.ID, domain)
 				return &RedirectBlockedError{Domain: domain, IsPrivate: true}
 			}
-			// Default redirect limit (10)
 			if len(via) >= 10 {
 				return http.ErrUseLastResponse
 			}
@@ -141,35 +149,48 @@ func (e *RedirectBlockedError) Error() string {
 
 // isPrivateIP checks if a hostname resolves to a private/local IP address
 func isPrivateIP(host string) bool {
-	// Block common private network patterns
-	// This is a simple check - for production, consider DNS resolution
-	privatePatterns := []string{
-		"localhost",
-		"127.",
-		"10.",
-		"172.16.", "172.17.", "172.18.", "172.19.",
-		"172.20.", "172.21.", "172.22.", "172.23.",
-		"172.24.", "172.25.", "172.26.", "172.27.",
-		"172.28.", "172.29.", "172.30.", "172.31.",
-		"192.168.",
-		"169.254.",
-		"::1",
-		"fc00:",
-		"fe80:",
+	hostLower := strings.ToLower(strings.TrimSpace(host))
+	if hostLower == "" {
+		return false
 	}
 
-	hostLower := host
-	for _, pattern := range privatePatterns {
-		if hostLower == pattern || len(hostLower) > len(pattern) && hostLower[:len(pattern)] == pattern {
+	if hostLower == "localhost" || strings.HasSuffix(hostLower, ".local") {
+		return true
+	}
+
+	if ip := net.ParseIP(hostLower); ip != nil {
+		return isPrivateIPAddr(ip)
+	}
+
+	ips, err := net.LookupIP(hostLower)
+	if err != nil {
+		return false
+	}
+
+	for _, ip := range ips {
+		if isPrivateIPAddr(ip) {
 			return true
 		}
 	}
 
-	// Also block .local domains
-	if len(host) > 6 && host[len(host)-6:] == ".local" {
+	return false
+}
+
+func isPrivateIPAddr(ip net.IP) bool {
+	if ip == nil {
+		return false
+	}
+	if ip.IsLoopback() ||
+		ip.IsPrivate() ||
+		ip.IsLinkLocalUnicast() ||
+		ip.IsLinkLocalMulticast() ||
+		ip.IsMulticast() ||
+		ip.IsUnspecified() {
+		return true
+	}
+	if !ip.IsGlobalUnicast() {
 		return true
 	}
-
 	return false
 }
 
@@ -201,18 +222,16 @@ func (r *ExtensionRuntime) SetSettings(settings map[string]interface{}) {
 	r.settings = settings
 }
 
-// RegisterAPIs registers all sandboxed APIs to the Goja VM
 func (r *ExtensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	r.vm = vm
 
-	// HTTP client (sandboxed to allowed domains)
 	httpObj := vm.NewObject()
 	httpObj.Set("get", r.httpGet)
 	httpObj.Set("post", r.httpPost)
 	httpObj.Set("put", r.httpPut)
 	httpObj.Set("delete", r.httpDelete)
 	httpObj.Set("patch", r.httpPatch)
-	httpObj.Set("request", r.httpRequest) // Generic HTTP request (GET, POST, PUT, DELETE, etc.)
+	httpObj.Set("request", r.httpRequest)
 	httpObj.Set("clearCookies", r.httpClearCookies)
 	vm.Set("http", httpObj)
 
@@ -222,7 +241,6 @@ func (r *ExtensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	storageObj.Set("remove", r.storageRemove)
 	vm.Set("storage", storageObj)
 
-	// Secure Credentials API (encrypted storage for sensitive data)
 	credentialsObj := vm.NewObject()
 	credentialsObj.Set("store", r.credentialsStore)
 	credentialsObj.Set("get", r.credentialsGet)
@@ -237,14 +255,12 @@ func (r *ExtensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	authObj.Set("clearAuth", r.authClear)
 	authObj.Set("isAuthenticated", r.authIsAuthenticated)
 	authObj.Set("getTokens", r.authGetTokens)
-	// PKCE support
 	authObj.Set("generatePKCE", r.authGeneratePKCE)
 	authObj.Set("getPKCE", r.authGetPKCE)
 	authObj.Set("startOAuthWithPKCE", r.authStartOAuthWithPKCE)
 	authObj.Set("exchangeCodeWithPKCE", r.authExchangeCodeWithPKCE)
 	vm.Set("auth", authObj)
 
-	// File operations (sandboxed)
 	fileObj := vm.NewObject()
 	fileObj.Set("download", r.fileDownload)
 	fileObj.Set("exists", r.fileExists)
@@ -262,7 +278,6 @@ func (r *ExtensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	ffmpegObj.Set("convert", r.ffmpegConvert)
 	vm.Set("ffmpeg", ffmpegObj)
 
-	// Track matching API
 	matchingObj := vm.NewObject()
 	matchingObj.Set("compareStrings", r.matchingCompareStrings)
 	matchingObj.Set("compareDuration", r.matchingCompareDuration)
@@ -279,14 +294,12 @@ func (r *ExtensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	utilsObj.Set("hmacSHA1", r.hmacSHA1)
 	utilsObj.Set("parseJSON", r.parseJSON)
 	utilsObj.Set("stringifyJSON", r.stringifyJSON)
-	// Crypto utilities for developers
 	utilsObj.Set("encrypt", r.cryptoEncrypt)
 	utilsObj.Set("decrypt", r.cryptoDecrypt)
 	utilsObj.Set("generateKey", r.cryptoGenerateKey)
 	utilsObj.Set("randomUserAgent", r.randomUserAgent)
 	vm.Set("utils", utilsObj)
 
-	// Log object (already set in extension_manager.go, but we can enhance it)
 	logObj := vm.NewObject()
 	logObj.Set("debug", r.logDebug)
 	logObj.Set("info", r.logInfo)
@@ -298,10 +311,6 @@ func (r *ExtensionRuntime) RegisterAPIs(vm *goja.Runtime) {
 	gobackendObj.Set("sanitizeFilename", r.sanitizeFilenameWrapper)
 	vm.Set("gobackend", gobackendObj)
 
-	// ==================== Browser-like Polyfills ====================
-	// These make porting browser/Node.js libraries easier
-
-	// Global fetch() - Promise-style HTTP API (browser-compatible)
 	vm.Set("fetch", r.fetchPolyfill)
 
 	vm.Set("atob", r.atobPolyfill)

go_backend/extension_runtime_auth.go

@@ -18,6 +18,43 @@ import (
 
 // ==================== Auth API (OAuth Support) ====================
 
+func validateExtensionAuthURL(urlStr string) error {
+	parsed, err := url.Parse(urlStr)
+	if err != nil {
+		return fmt.Errorf("invalid auth URL: %w", err)
+	}
+
+	if parsed.Scheme != "https" {
+		return fmt.Errorf("invalid auth URL: only https is allowed")
+	}
+
+	host := parsed.Hostname()
+	if host == "" {
+		return fmt.Errorf("invalid auth URL: hostname is required")
+	}
+
+	if parsed.User != nil {
+		return fmt.Errorf("invalid auth URL: embedded credentials are not allowed")
+	}
+
+	if isPrivateIP(host) {
+		return fmt.Errorf("invalid auth URL: private/local network is not allowed")
+	}
+
+	return nil
+}
+
+func summarizeURLForLog(urlStr string) string {
+	parsed, err := url.Parse(urlStr)
+	if err != nil {
+		return urlStr
+	}
+	if parsed.Host == "" {
+		return parsed.Scheme + "://"
+	}
+	return fmt.Sprintf("%s://%s%s", parsed.Scheme, parsed.Host, parsed.Path)
+}
+
 func (r *ExtensionRuntime) authOpenUrl(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -32,6 +69,13 @@ func (r *ExtensionRuntime) authOpenUrl(call goja.FunctionCall) goja.Value {
 		callbackURL = call.Arguments[1].String()
 	}
 
+	if err := validateExtensionAuthURL(authURL); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
 	pendingAuthRequestsMu.Lock()
 	pendingAuthRequests[r.extensionID] = &PendingAuthRequest{
 		ExtensionID: r.extensionID,
@@ -50,7 +94,7 @@ func (r *ExtensionRuntime) authOpenUrl(call goja.FunctionCall) goja.Value {
 	state.AuthCode = ""
 	extensionAuthStateMu.Unlock()
 
-	GoLog("[Extension:%s] Auth URL requested: %s\n", r.extensionID, authURL)
+	GoLog("[Extension:%s] Auth URL requested: %s\n", r.extensionID, summarizeURLForLog(authURL))
 
 	return r.vm.ToValue(map[string]interface{}{
 		"success": true,
@@ -70,13 +114,11 @@ func (r *ExtensionRuntime) authGetCode(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(state.AuthCode)
 }
 
-// authSetCode sets auth code and tokens (can be called by extension after token exchange)
 func (r *ExtensionRuntime) authSetCode(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(false)
 	}
 
-	// Can accept either just auth code or an object with tokens
 	arg := call.Arguments[0].Export()
 
 	extensionAuthStateMu.Lock()
@@ -123,7 +165,6 @@ func (r *ExtensionRuntime) authClear(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(true)
 }
 
-// authIsAuthenticated checks if extension has valid auth
 func (r *ExtensionRuntime) authIsAuthenticated(call goja.FunctionCall) goja.Value {
 	extensionAuthStateMu.RLock()
 	defer extensionAuthStateMu.RUnlock()
@@ -196,7 +237,6 @@ func generatePKCEChallenge(verifier string) string {
 }
 
 func (r *ExtensionRuntime) authGeneratePKCE(call goja.FunctionCall) goja.Value {
-	// Default length is 64 characters
 	length := 64
 	if len(call.Arguments) > 0 && !goja.IsUndefined(call.Arguments[0]) {
 		if l, ok := call.Arguments[0].Export().(float64); ok && l >= 43 && l <= 128 {
@@ -249,9 +289,7 @@ func (r *ExtensionRuntime) authGetPKCE(call goja.FunctionCall) goja.Value {
 	})
 }
 
-// authStartOAuthWithPKCE is a high-level helper that generates PKCE and opens OAuth URL
 // config: { authUrl, clientId, redirectUri, scope, extraParams }
-// Returns: { success, authUrl, pkce: { verifier, challenge } }
 func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -269,7 +307,6 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 		})
 	}
 
-	// Required fields
 	authURL, _ := config["authUrl"].(string)
 	clientID, _ := config["clientId"].(string)
 	redirectURI, _ := config["redirectUri"].(string)
@@ -280,12 +317,16 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 			"error":   "authUrl, clientId, and redirectUri are required",
 		})
 	}
+	if err := validateExtensionAuthURL(authURL); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
 
-	// Optional fields
 	scope, _ := config["scope"].(string)
 	extraParams, _ := config["extraParams"].(map[string]interface{})
 
-	// Generate PKCE
 	verifier, err := generatePKCEVerifier(64)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -295,7 +336,6 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 	}
 	challenge := generatePKCEChallenge(verifier)
 
-	// Store PKCE in auth state
 	extensionAuthStateMu.Lock()
 	state, exists := extensionAuthState[r.extensionID]
 	if !exists {
@@ -304,10 +344,9 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 	}
 	state.PKCEVerifier = verifier
 	state.PKCEChallenge = challenge
-	state.AuthCode = "" // Clear any previous auth code
+	state.AuthCode = ""
 	extensionAuthStateMu.Unlock()
 
-	// Build OAuth URL with PKCE parameters
 	parsedURL, err := url.Parse(authURL)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -327,7 +366,6 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 		query.Set("scope", scope)
 	}
 
-	// Add extra params
 	for k, v := range extraParams {
 		query.Set(k, fmt.Sprintf("%v", v))
 	}
@@ -335,7 +373,6 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 	parsedURL.RawQuery = query.Encode()
 	fullAuthURL := parsedURL.String()
 
-	// Store pending auth request for Flutter
 	pendingAuthRequestsMu.Lock()
 	pendingAuthRequests[r.extensionID] = &PendingAuthRequest{
 		ExtensionID: r.extensionID,
@@ -344,7 +381,7 @@ func (r *ExtensionRuntime) authStartOAuthWithPKCE(call goja.FunctionCall) goja.V
 	}
 	pendingAuthRequestsMu.Unlock()
 
-	GoLog("[Extension:%s] PKCE OAuth started: %s\n", r.extensionID, fullAuthURL)
+	GoLog("[Extension:%s] PKCE OAuth started: %s\n", r.extensionID, summarizeURLForLog(fullAuthURL))
 
 	return r.vm.ToValue(map[string]interface{}{
 		"success": true,
@@ -454,13 +491,17 @@ func (r *ExtensionRuntime) authExchangeCodeWithPKCE(call goja.FunctionCall) goja
 			"error":   err.Error(),
 		})
 	}
+	bodyPreview := sanitizeSensitiveLogText(string(body))
+	if len(bodyPreview) > 1000 {
+		bodyPreview = bodyPreview[:1000] + "...[truncated]"
+	}
 
 	var tokenResp map[string]interface{}
 	if err := json.Unmarshal(body, &tokenResp); err != nil {
 		return r.vm.ToValue(map[string]interface{}{
 			"success": false,
 			"error":   fmt.Sprintf("failed to parse token response: %v", err),
-			"body":    string(body),
+			"body":    bodyPreview,
 		})
 	}
 
@@ -481,7 +522,7 @@ func (r *ExtensionRuntime) authExchangeCodeWithPKCE(call goja.FunctionCall) goja
 		return r.vm.ToValue(map[string]interface{}{
 			"success": false,
 			"error":   "no access_token in response",
-			"body":    string(body),
+			"body":    bodyPreview,
 		})
 	}
 

go_backend/extension_runtime_ffmpeg.go

@@ -64,7 +64,6 @@ func (r *ExtensionRuntime) ffmpegExecute(call goja.FunctionCall) goja.Value {
 
 	command := call.Arguments[0].String()
 
-	// Generate unique command ID
 	ffmpegCommandsMu.Lock()
 	ffmpegCommandID++
 	cmdID := fmt.Sprintf("%s_%d", r.extensionID, ffmpegCommandID)
@@ -77,7 +76,6 @@ func (r *ExtensionRuntime) ffmpegExecute(call goja.FunctionCall) goja.Value {
 
 	GoLog("[Extension:%s] FFmpeg command queued: %s\n", r.extensionID, cmdID)
 
-	// Wait for completion (with timeout)
 	timeout := 5 * time.Minute
 	start := time.Now()
 	for {
@@ -97,7 +95,6 @@ func (r *ExtensionRuntime) ffmpegExecute(call goja.FunctionCall) goja.Value {
 			}
 			ffmpegCommandsMu.RUnlock()
 
-			// Cleanup
 			ClearFFmpegCommand(cmdID)
 			return r.vm.ToValue(result)
 		}
@@ -124,7 +121,6 @@ func (r *ExtensionRuntime) ffmpegGetInfo(call goja.FunctionCall) goja.Value {
 
 	filePath := call.Arguments[0].String()
 
-	// Use Go's built-in audio quality function
 	quality, err := GetAudioQuality(filePath)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -153,7 +149,6 @@ func (r *ExtensionRuntime) ffmpegConvert(call goja.FunctionCall) goja.Value {
 	inputPath := call.Arguments[0].String()
 	outputPath := call.Arguments[1].String()
 
-	// Get options if provided
 	options := map[string]interface{}{}
 	if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) && !goja.IsNull(call.Arguments[2]) {
 		if opts, ok := call.Arguments[2].Export().(map[string]interface{}); ok {
@@ -161,36 +156,29 @@ func (r *ExtensionRuntime) ffmpegConvert(call goja.FunctionCall) goja.Value {
 		}
 	}
 
-	// Build FFmpeg command
 	var cmdParts []string
 	cmdParts = append(cmdParts, "-i", fmt.Sprintf("%q", inputPath))
 
-	// Audio codec
 	if codec, ok := options["codec"].(string); ok {
 		cmdParts = append(cmdParts, "-c:a", codec)
 	}
 
-	// Bitrate
 	if bitrate, ok := options["bitrate"].(string); ok {
 		cmdParts = append(cmdParts, "-b:a", bitrate)
 	}
 
-	// Sample rate
 	if sampleRate, ok := options["sample_rate"].(float64); ok {
 		cmdParts = append(cmdParts, "-ar", fmt.Sprintf("%d", int(sampleRate)))
 	}
 
-	// Channels
 	if channels, ok := options["channels"].(float64); ok {
 		cmdParts = append(cmdParts, "-ac", fmt.Sprintf("%d", int(channels)))
 	}
 
-	// Overwrite output
 	cmdParts = append(cmdParts, "-y", fmt.Sprintf("%q", outputPath))
 
 	command := strings.Join(cmdParts, " ")
 
-	// Execute via ffmpegExecute
 	execCall := goja.FunctionCall{
 		Arguments: []goja.Value{r.vm.ToValue(command)},
 	}

go_backend/extension_runtime_file.go

@@ -15,7 +15,6 @@ import (
 
 // ==================== File API (Sandboxed) ====================
 
-// List of allowed directories for file operations (set by Go backend for download operations)
 var (
 	allowedDownloadDirs   []string
 	allowedDownloadDirsMu sync.RWMutex
@@ -42,18 +41,40 @@ func isPathInAllowedDirs(absPath string) bool {
 	defer allowedDownloadDirsMu.RUnlock()
 
 	for _, allowedDir := range allowedDownloadDirs {
-		if strings.HasPrefix(absPath, allowedDir) {
+		if isPathWithinBase(allowedDir, absPath) {
 			return true
 		}
 	}
 	return false
 }
 
-// validatePath checks if the path is within the extension's sandbox
-// Security: Absolute paths are BLOCKED unless they're in allowed download directories
-// Extensions should use relative paths for their own data storage
+func isPathWithinBase(baseDir, targetPath string) bool {
+	baseAbs, err := filepath.Abs(baseDir)
+	if err != nil {
+		return false
+	}
+	targetAbs, err := filepath.Abs(targetPath)
+	if err != nil {
+		return false
+	}
+
+	rel, err := filepath.Rel(baseAbs, targetAbs)
+	if err != nil {
+		return false
+	}
+	rel = filepath.Clean(rel)
+	if rel == "." {
+		return true
+	}
+
+	prefix := ".." + string(filepath.Separator)
+	if rel == ".." || strings.HasPrefix(rel, prefix) {
+		return false
+	}
+	return true
+}
+
 func (r *ExtensionRuntime) validatePath(path string) (string, error) {
-	// Check if extension has file permission
 	if !r.manifest.Permissions.File {
 		return "", fmt.Errorf("file access denied: extension does not have 'file' permission")
 	}
@@ -81,7 +102,7 @@ func (r *ExtensionRuntime) validatePath(path string) (string, error) {
 	}
 
 	absDataDir, _ := filepath.Abs(r.dataDir)
-	if !strings.HasPrefix(absPath, absDataDir) {
+	if !isPathWithinBase(absDataDir, absPath) {
 		return "", fmt.Errorf("file access denied: path '%s' is outside sandbox", path)
 	}
 
@@ -327,7 +348,6 @@ func (r *ExtensionRuntime) fileWrite(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Create directory if needed
 	dir := filepath.Dir(fullPath)
 	if err := os.MkdirAll(dir, 0755); err != nil {
 		return r.vm.ToValue(map[string]interface{}{

go_backend/extension_runtime_http.go

@@ -14,23 +14,33 @@ import (
 
 // ==================== HTTP API (Sandboxed) ====================
 
-// HTTPResponse represents the response from an HTTP request
 type HTTPResponse struct {
 	StatusCode int               `json:"statusCode"`
 	Body       string            `json:"body"`
 	Headers    map[string]string `json:"headers"`
 }
 
-// validateDomain checks if the domain is allowed by the extension's permissions
 func (r *ExtensionRuntime) validateDomain(urlStr string) error {
 	parsed, err := url.Parse(urlStr)
 	if err != nil {
 		return fmt.Errorf("invalid URL: %w", err)
 	}
 
-	domain := parsed.Hostname()
+	if parsed.Scheme == "" {
+		return fmt.Errorf("invalid URL: scheme is required")
+	}
+	if parsed.Scheme != "https" {
+		return fmt.Errorf("network access denied: only https is allowed")
+	}
+	if parsed.User != nil {
+		return fmt.Errorf("invalid URL: embedded credentials are not allowed")
+	}
+
+	domain := parsed.Hostname()
+	if domain == "" {
+		return fmt.Errorf("invalid URL: hostname is required")
+	}
 
-	// Block private/local network access (SSRF protection)
 	if isPrivateIP(domain) {
 		return fmt.Errorf("network access denied: private/local network '%s' not allowed", domain)
 	}
@@ -42,7 +52,6 @@ func (r *ExtensionRuntime) validateDomain(urlStr string) error {
 	return nil
 }
 
-// httpGet performs a GET request (sandboxed)
 func (r *ExtensionRuntime) httpGet(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -76,16 +85,14 @@ func (r *ExtensionRuntime) httpGet(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Set headers - user headers first
 	for k, v := range headers {
 		req.Header.Set(k, v)
 	}
-	// Only set default User-Agent if not provided by extension
+
 	if req.Header.Get("User-Agent") == "" {
 		req.Header.Set("User-Agent", "Spotiflac-Extension/1.0")
 	}
 
-	// Execute request
 	resp, err := r.httpClient.Do(req)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -101,26 +108,24 @@ func (r *ExtensionRuntime) httpGet(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Extract response headers - return all values as arrays for multi-value headers (cookies, etc.)
 	respHeaders := make(map[string]interface{})
 	for k, v := range resp.Header {
 		if len(v) == 1 {
 			respHeaders[k] = v[0]
 		} else {
-			respHeaders[k] = v // Return as array if multiple values
+			respHeaders[k] = v
 		}
 	}
 
 	return r.vm.ToValue(map[string]interface{}{
 		"statusCode": resp.StatusCode,
-		"status":     resp.StatusCode, // Alias for convenience
+		"status":     resp.StatusCode,
 		"ok":         resp.StatusCode >= 200 && resp.StatusCode < 300,
 		"body":       string(body),
 		"headers":    respHeaders,
 	})
 }
 
-// httpPost performs a POST request (sandboxed)
 func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -137,7 +142,6 @@ func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Get body if provided - support both string and object
 	var bodyStr string
 	if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) && !goja.IsNull(call.Arguments[1]) {
 		bodyArg := call.Arguments[1].Export()
@@ -145,7 +149,6 @@ func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 		case string:
 			bodyStr = v
 		case map[string]interface{}, []interface{}:
-			// Auto-stringify objects and arrays to JSON
 			jsonBytes, err := json.Marshal(v)
 			if err != nil {
 				return r.vm.ToValue(map[string]interface{}{
@@ -154,12 +157,10 @@ func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 			}
 			bodyStr = string(jsonBytes)
 		default:
-			// Fallback to string conversion
 			bodyStr = call.Arguments[1].String()
 		}
 	}
 
-	// Get headers if provided
 	headers := make(map[string]string)
 	if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) && !goja.IsNull(call.Arguments[2]) {
 		headersObj := call.Arguments[2].Export()
@@ -177,11 +178,10 @@ func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Set headers - user headers first
 	for k, v := range headers {
 		req.Header.Set(k, v)
 	}
-	// Only set defaults if not provided by extension
+
 	if req.Header.Get("User-Agent") == "" {
 		req.Header.Set("User-Agent", "Spotiflac-Extension/1.0")
 	}
@@ -189,7 +189,6 @@ func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 		req.Header.Set("Content-Type", "application/json")
 	}
 
-	// Execute request
 	resp, err := r.httpClient.Do(req)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -205,19 +204,18 @@ func (r *ExtensionRuntime) httpPost(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Extract response headers - return all values as arrays for multi-value headers
 	respHeaders := make(map[string]interface{})
 	for k, v := range resp.Header {
 		if len(v) == 1 {
 			respHeaders[k] = v[0]
 		} else {
-			respHeaders[k] = v // Return as array if multiple values
+			respHeaders[k] = v
 		}
 	}
 
 	return r.vm.ToValue(map[string]interface{}{
 		"statusCode": resp.StatusCode,
-		"status":     resp.StatusCode, // Alias for convenience
+		"status":     resp.StatusCode,
 		"ok":         resp.StatusCode >= 200 && resp.StatusCode < 300,
 		"body":       string(body),
 		"headers":    respHeaders,
@@ -240,27 +238,22 @@ func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Default options
 	method := "GET"
 	var bodyStr string
 	headers := make(map[string]string)
 
-	// Parse options if provided
 	if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) && !goja.IsNull(call.Arguments[1]) {
 		optionsObj := call.Arguments[1].Export()
 		if opts, ok := optionsObj.(map[string]interface{}); ok {
-			// Get method
 			if m, ok := opts["method"].(string); ok {
 				method = strings.ToUpper(m)
 			}
 
-			// Get body - support both string and object
 			if bodyArg, ok := opts["body"]; ok && bodyArg != nil {
 				switch v := bodyArg.(type) {
 				case string:
 					bodyStr = v
 				case map[string]interface{}, []interface{}:
-					// Auto-stringify objects and arrays to JSON
 					jsonBytes, err := json.Marshal(v)
 					if err != nil {
 						return r.vm.ToValue(map[string]interface{}{
@@ -273,7 +266,6 @@ func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 				}
 			}
 
-			// Get headers
 			if h, ok := opts["headers"].(map[string]interface{}); ok {
 				for k, v := range h {
 					headers[k] = fmt.Sprintf("%v", v)
@@ -282,7 +274,6 @@ func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 		}
 	}
 
-	// Create request
 	var reqBody io.Reader
 	if bodyStr != "" {
 		reqBody = strings.NewReader(bodyStr)
@@ -295,11 +286,10 @@ func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Set headers - user headers first
 	for k, v := range headers {
 		req.Header.Set(k, v)
 	}
-	// Only set defaults if not provided by extension
+
 	if req.Header.Get("User-Agent") == "" {
 		req.Header.Set("User-Agent", "Spotiflac-Extension/1.0")
 	}
@@ -307,7 +297,6 @@ func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 		req.Header.Set("Content-Type", "application/json")
 	}
 
-	// Execute request
 	resp, err := r.httpClient.Do(req)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -323,20 +312,18 @@ func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Extract response headers - return all values as arrays for multi-value headers
 	respHeaders := make(map[string]interface{})
 	for k, v := range resp.Header {
 		if len(v) == 1 {
 			respHeaders[k] = v[0]
 		} else {
-			respHeaders[k] = v // Return as array if multiple values
+			respHeaders[k] = v
 		}
 	}
 
-	// Return response with helper properties
 	return r.vm.ToValue(map[string]interface{}{
 		"statusCode": resp.StatusCode,
-		"status":     resp.StatusCode, // Alias for convenience
+		"status":     resp.StatusCode,
 		"ok":         resp.StatusCode >= 200 && resp.StatusCode < 300,
 		"body":       string(body),
 		"headers":    respHeaders,
@@ -347,7 +334,6 @@ func (r *ExtensionRuntime) httpPut(call goja.FunctionCall) goja.Value {
 	return r.httpMethodShortcut("PUT", call)
 }
 
-// httpDelete performs a DELETE request (shortcut for http.request with method: "DELETE")
 func (r *ExtensionRuntime) httpDelete(call goja.FunctionCall) goja.Value {
 	return r.httpMethodShortcut("DELETE", call)
 }
@@ -356,8 +342,6 @@ func (r *ExtensionRuntime) httpPatch(call goja.FunctionCall) goja.Value {
 	return r.httpMethodShortcut("PATCH", call)
 }
 
-// httpMethodShortcut is a helper for PUT/DELETE/PATCH shortcuts
-// Signature: http.put(url, body, headers) / http.delete(url, headers) / http.patch(url, body, headers)
 func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -377,9 +361,7 @@ func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 	var bodyStr string
 	headers := make(map[string]string)
 
-	// For DELETE, second arg is headers; for PUT/PATCH, second arg is body
 	if method == "DELETE" {
-		// http.delete(url, headers)
 		if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) && !goja.IsNull(call.Arguments[1]) {
 			headersObj := call.Arguments[1].Export()
 			if h, ok := headersObj.(map[string]interface{}); ok {
@@ -389,7 +371,6 @@ func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 			}
 		}
 	} else {
-		// http.put(url, body, headers) / http.patch(url, body, headers)
 		if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) && !goja.IsNull(call.Arguments[1]) {
 			bodyArg := call.Arguments[1].Export()
 			switch v := bodyArg.(type) {
@@ -418,7 +399,6 @@ func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 		}
 	}
 
-	// Create request
 	var reqBody io.Reader
 	if bodyStr != "" {
 		reqBody = strings.NewReader(bodyStr)
@@ -431,7 +411,6 @@ func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 		})
 	}
 
-	// Set headers - user headers first
 	for k, v := range headers {
 		req.Header.Set(k, v)
 	}
@@ -442,7 +421,6 @@ func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 		req.Header.Set("Content-Type", "application/json")
 	}
 
-	// Execute request
 	resp, err := r.httpClient.Do(req)
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
@@ -458,7 +436,6 @@ func (r *ExtensionRuntime) httpMethodShortcut(method string, call goja.FunctionC
 		})
 	}
 
-	// Extract response headers
 	respHeaders := make(map[string]interface{})
 	for k, v := range resp.Header {
 		if len(v) == 1 {

go_backend/extension_runtime_matching.go

@@ -9,7 +9,6 @@ import (
 
 // ==================== Track Matching API ====================
 
-// matchingCompareStrings compares two strings with fuzzy matching
 func (r *ExtensionRuntime) matchingCompareStrings(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue(0.0)
@@ -22,12 +21,10 @@ func (r *ExtensionRuntime) matchingCompareStrings(call goja.FunctionCall) goja.V
 		return r.vm.ToValue(1.0)
 	}
 
-	// Calculate Levenshtein distance-based similarity
 	similarity := calculateStringSimilarity(str1, str2)
 	return r.vm.ToValue(similarity)
 }
 
-// matchingCompareDuration compares two durations with tolerance
 func (r *ExtensionRuntime) matchingCompareDuration(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue(false)
@@ -36,8 +33,7 @@ func (r *ExtensionRuntime) matchingCompareDuration(call goja.FunctionCall) goja.
 	dur1 := int(call.Arguments[0].ToInteger())
 	dur2 := int(call.Arguments[1].ToInteger())
 
-	// Default tolerance: 3 seconds
-	tolerance := 3000 // milliseconds
+	tolerance := 3000
 	if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) {
 		tolerance = int(call.Arguments[2].ToInteger())
 	}
@@ -50,7 +46,6 @@ func (r *ExtensionRuntime) matchingCompareDuration(call goja.FunctionCall) goja.
 	return r.vm.ToValue(diff <= tolerance)
 }
 
-// matchingNormalizeString normalizes a string for comparison
 func (r *ExtensionRuntime) matchingNormalizeString(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -61,7 +56,6 @@ func (r *ExtensionRuntime) matchingNormalizeString(call goja.FunctionCall) goja.
 	return r.vm.ToValue(normalized)
 }
 
-// calculateStringSimilarity calculates similarity between two strings (0-1)
 func calculateStringSimilarity(s1, s2 string) float64 {
 	if len(s1) == 0 && len(s2) == 0 {
 		return 1.0
@@ -70,7 +64,6 @@ func calculateStringSimilarity(s1, s2 string) float64 {
 		return 0.0
 	}
 
-	// Use Levenshtein distance
 	distance := levenshteinDistance(s1, s2)
 	maxLen := len(s1)
 	if len(s2) > maxLen {
@@ -80,7 +73,6 @@ func calculateStringSimilarity(s1, s2 string) float64 {
 	return 1.0 - float64(distance)/float64(maxLen)
 }
 
-// levenshteinDistance calculates the Levenshtein distance between two strings
 func levenshteinDistance(s1, s2 string) int {
 	if len(s1) == 0 {
 		return len(s2)
@@ -89,7 +81,6 @@ func levenshteinDistance(s1, s2 string) int {
 		return len(s1)
 	}
 
-	// Create matrix
 	matrix := make([][]int, len(s1)+1)
 	for i := range matrix {
 		matrix[i] = make([]int, len(s2)+1)
@@ -99,7 +90,6 @@ func levenshteinDistance(s1, s2 string) int {
 		matrix[0][j] = j
 	}
 
-	// Fill matrix
 	for i := 1; i <= len(s1); i++ {
 		for j := 1; j <= len(s2); j++ {
 			cost := 1
@@ -107,9 +97,9 @@ func levenshteinDistance(s1, s2 string) int {
 				cost = 0
 			}
 			matrix[i][j] = min(
-				matrix[i-1][j]+1,      // deletion
-				matrix[i][j-1]+1,      // insertion
-				matrix[i-1][j-1]+cost, // substitution
+				matrix[i-1][j]+1,
+				matrix[i][j-1]+1,
+				matrix[i-1][j-1]+cost,
 			)
 		}
 	}
@@ -117,12 +107,9 @@ func levenshteinDistance(s1, s2 string) int {
 	return matrix[len(s1)][len(s2)]
 }
 
-// normalizeStringForMatching normalizes a string for comparison
 func normalizeStringForMatching(s string) string {
-	// Convert to lowercase
 	s = strings.ToLower(s)
 
-	// Remove common suffixes/prefixes
 	suffixes := []string{
 		" (remastered)", " (remaster)", " - remastered", " - remaster",
 		" (deluxe)", " (deluxe edition)", " - deluxe", " - deluxe edition",
@@ -136,7 +123,6 @@ func normalizeStringForMatching(s string) string {
 		}
 	}
 
-	// Remove special characters
 	var result strings.Builder
 	for _, r := range s {
 		if (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') || r == ' ' {
@@ -144,7 +130,6 @@ func normalizeStringForMatching(s string) string {
 		}
 	}
 
-	// Collapse multiple spaces
 	s = strings.Join(strings.Fields(result.String()), " ")
 
 	return strings.TrimSpace(s)

go_backend/extension_runtime_polyfills.go

@@ -25,14 +25,11 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 	}
 
 	urlStr := call.Arguments[0].String()
-
-	// Validate domain
 	if err := r.validateDomain(urlStr); err != nil {
 		GoLog("[Extension:%s] fetch blocked: %v\n", r.extensionID, err)
 		return r.createFetchError(err.Error())
 	}
 
-	// Parse options
 	method := "GET"
 	var bodyStr string
 	headers := make(map[string]string)
@@ -40,7 +37,6 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) && !goja.IsNull(call.Arguments[1]) {
 		optionsObj := call.Arguments[1].Export()
 		if opts, ok := optionsObj.(map[string]interface{}); ok {
-			// Method
 			if m, ok := opts["method"].(string); ok {
 				method = strings.ToUpper(m)
 			}
@@ -61,7 +57,6 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 				}
 			}
 
-			// Headers
 			if h, ok := opts["headers"]; ok && h != nil {
 				switch hv := h.(type) {
 				case map[string]interface{}:
@@ -73,7 +68,6 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 		}
 	}
 
-	// Create HTTP request
 	var reqBody io.Reader
 	if bodyStr != "" {
 		reqBody = strings.NewReader(bodyStr)
@@ -84,11 +78,9 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 		return r.createFetchError(err.Error())
 	}
 
-	// Set headers - user headers first
 	for k, v := range headers {
 		req.Header.Set(k, v)
 	}
-	// Set defaults if not provided
 	if req.Header.Get("User-Agent") == "" {
 		req.Header.Set("User-Agent", "SpotiFLAC-Extension/1.0")
 	}
@@ -96,20 +88,17 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 		req.Header.Set("Content-Type", "application/json")
 	}
 
-	// Execute request
 	resp, err := r.httpClient.Do(req)
 	if err != nil {
 		return r.createFetchError(err.Error())
 	}
 	defer resp.Body.Close()
 
-	// Read body
 	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return r.createFetchError(err.Error())
 	}
 
-	// Extract response headers
 	respHeaders := make(map[string]interface{})
 	for k, v := range resp.Header {
 		if len(v) == 1 {
@@ -119,7 +108,6 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 		}
 	}
 
-	// Create Response object (browser-compatible)
 	responseObj := r.vm.NewObject()
 	responseObj.Set("ok", resp.StatusCode >= 200 && resp.StatusCode < 300)
 	responseObj.Set("status", resp.StatusCode)
@@ -127,15 +115,12 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 	responseObj.Set("headers", respHeaders)
 	responseObj.Set("url", urlStr)
 
-	// Store body for methods
 	bodyString := string(body)
 
-	// text() method - returns body as string
 	responseObj.Set("text", func(call goja.FunctionCall) goja.Value {
 		return r.vm.ToValue(bodyString)
 	})
 
-	// json() method - parses body as JSON
 	responseObj.Set("json", func(call goja.FunctionCall) goja.Value {
 		var result interface{}
 		if err := json.Unmarshal(body, &result); err != nil {
@@ -145,9 +130,7 @@ func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
 		return r.vm.ToValue(result)
 	})
 
-	// arrayBuffer() method - returns body as array (simplified)
 	responseObj.Set("arrayBuffer", func(call goja.FunctionCall) goja.Value {
-		// Return as array of bytes
 		byteArray := make([]interface{}, len(body))
 		for i, b := range body {
 			byteArray[i] = int(b)
@@ -182,7 +165,6 @@ func (r *ExtensionRuntime) atobPolyfill(call goja.FunctionCall) goja.Value {
 	input := call.Arguments[0].String()
 	decoded, err := base64.StdEncoding.DecodeString(input)
 	if err != nil {
-		// Try URL-safe base64
 		decoded, err = base64.URLEncoding.DecodeString(input)
 		if err != nil {
 			GoLog("[Extension:%s] atob decode error: %v\n", r.extensionID, err)
@@ -203,12 +185,10 @@ func (r *ExtensionRuntime) btoaPolyfill(call goja.FunctionCall) goja.Value {
 
 // registerTextEncoderDecoder registers TextEncoder and TextDecoder classes
 func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
-	// TextEncoder constructor
 	vm.Set("TextEncoder", func(call goja.ConstructorCall) *goja.Object {
 		encoder := call.This
 		encoder.Set("encoding", "utf-8")
 
-		// encode() method - string to Uint8Array
 		encoder.Set("encode", func(call goja.FunctionCall) goja.Value {
 			if len(call.Arguments) < 1 {
 				return vm.ToValue([]byte{})
@@ -216,7 +196,6 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 			input := call.Arguments[0].String()
 			bytes := []byte(input)
 
-			// Return as array (Uint8Array-like)
 			result := make([]interface{}, len(bytes))
 			for i, b := range bytes {
 				result[i] = int(b)
@@ -224,7 +203,6 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 			return vm.ToValue(result)
 		})
 
-		// encodeInto() method
 		encoder.Set("encodeInto", func(call goja.FunctionCall) goja.Value {
 			// Simplified implementation
 			if len(call.Arguments) < 2 {
@@ -240,11 +218,9 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 		return nil
 	})
 
-	// TextDecoder constructor
 	vm.Set("TextDecoder", func(call goja.ConstructorCall) *goja.Object {
 		decoder := call.This
 
-		// Get encoding from arguments (default: utf-8)
 		encoding := "utf-8"
 		if len(call.Arguments) > 0 && !goja.IsUndefined(call.Arguments[0]) {
 			encoding = call.Arguments[0].String()
@@ -253,13 +229,11 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 		decoder.Set("fatal", false)
 		decoder.Set("ignoreBOM", false)
 
-		// decode() method - Uint8Array to string
 		decoder.Set("decode", func(call goja.FunctionCall) goja.Value {
 			if len(call.Arguments) < 1 {
 				return vm.ToValue("")
 			}
 
-			// Handle different input types
 			input := call.Arguments[0].Export()
 			var bytes []byte
 
@@ -279,7 +253,6 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 					}
 				}
 			case string:
-				// Already a string, just return it
 				return vm.ToValue(v)
 			default:
 				return vm.ToValue("")
@@ -292,7 +265,6 @@ func (r *ExtensionRuntime) registerTextEncoderDecoder(vm *goja.Runtime) {
 	})
 }
 
-// registerURLClass registers the URL class for URL parsing
 func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 	vm.Set("URL", func(call goja.ConstructorCall) *goja.Object {
 		urlObj := call.This
@@ -304,7 +276,6 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 
 		urlStr := call.Arguments[0].String()
 
-		// Handle relative URLs with base
 		if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) {
 			baseStr := call.Arguments[1].String()
 			baseURL, err := url.Parse(baseStr)
@@ -322,7 +293,6 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 			return nil
 		}
 
-		// Set URL properties
 		urlObj.Set("href", parsed.String())
 		urlObj.Set("protocol", parsed.Scheme+":")
 		urlObj.Set("host", parsed.Host)
@@ -342,10 +312,9 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 		password, _ := parsed.User.Password()
 		urlObj.Set("password", password)
 
-		// searchParams object
-		searchParams := vm.NewObject()
 		queryValues := parsed.Query()
 
+		searchParams := vm.NewObject()
 		searchParams.Set("get", func(call goja.FunctionCall) goja.Value {
 			if len(call.Arguments) < 1 {
 				return goja.Null()
@@ -379,12 +348,10 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 
 		urlObj.Set("searchParams", searchParams)
 
-		// toString method
 		urlObj.Set("toString", func(call goja.FunctionCall) goja.Value {
 			return vm.ToValue(parsed.String())
 		})
 
-		// toJSON method
 		urlObj.Set("toJSON", func(call goja.FunctionCall) goja.Value {
 			return vm.ToValue(parsed.String())
 		})
@@ -392,17 +359,14 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 		return nil
 	})
 
-	// URLSearchParams constructor
 	vm.Set("URLSearchParams", func(call goja.ConstructorCall) *goja.Object {
 		paramsObj := call.This
 		values := url.Values{}
 
-		// Parse initial value if provided
 		if len(call.Arguments) > 0 && !goja.IsUndefined(call.Arguments[0]) {
 			init := call.Arguments[0].Export()
 			switch v := init.(type) {
 			case string:
-				// Parse query string
 				parsed, _ := url.ParseQuery(strings.TrimPrefix(v, "?"))
 				values = parsed
 			case map[string]interface{}:
@@ -468,10 +432,6 @@ func (r *ExtensionRuntime) registerURLClass(vm *goja.Runtime) {
 // registerJSONGlobal ensures JSON global is properly set up
 func (r *ExtensionRuntime) registerJSONGlobal(vm *goja.Runtime) {
 	// JSON is already built-in to Goja, but we can enhance it
-	// This ensures JSON.parse and JSON.stringify work as expected
-
-	// The built-in JSON object should already work, but let's verify
-	// and add any missing functionality if needed
 	jsonScript := `
 		if (typeof JSON === 'undefined') {
 			var JSON = {

go_backend/extension_runtime_storage.go

@@ -17,12 +17,10 @@ import (
 
 // ==================== Storage API ====================
 
-// getStoragePath returns the path to the extension's storage file
 func (r *ExtensionRuntime) getStoragePath() string {
 	return filepath.Join(r.dataDir, "storage.json")
 }
 
-// loadStorage loads the storage data from disk
 func (r *ExtensionRuntime) loadStorage() (map[string]interface{}, error) {
 	storagePath := r.getStoragePath()
 	data, err := os.ReadFile(storagePath)
@@ -41,7 +39,6 @@ func (r *ExtensionRuntime) loadStorage() (map[string]interface{}, error) {
 	return storage, nil
 }
 
-// saveStorage saves the storage data to disk
 func (r *ExtensionRuntime) saveStorage(storage map[string]interface{}) error {
 	storagePath := r.getStoragePath()
 	data, err := json.MarshalIndent(storage, "", "  ")
@@ -49,10 +46,9 @@ func (r *ExtensionRuntime) saveStorage(storage map[string]interface{}) error {
 		return err
 	}
 
-	return os.WriteFile(storagePath, data, 0644)
+	return os.WriteFile(storagePath, data, 0600)
 }
 
-// storageGet retrieves a value from storage
 func (r *ExtensionRuntime) storageGet(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return goja.Undefined()
@@ -68,7 +64,6 @@ func (r *ExtensionRuntime) storageGet(call goja.FunctionCall) goja.Value {
 
 	value, exists := storage[key]
 	if !exists {
-		// Return default value if provided
 		if len(call.Arguments) > 1 {
 			return call.Arguments[1]
 		}
@@ -78,7 +73,6 @@ func (r *ExtensionRuntime) storageGet(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(value)
 }
 
-// storageSet stores a value in storage
 func (r *ExtensionRuntime) storageSet(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue(false)
@@ -103,7 +97,6 @@ func (r *ExtensionRuntime) storageSet(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(true)
 }
 
-// storageRemove removes a value from storage
 func (r *ExtensionRuntime) storageRemove(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(false)
@@ -127,19 +120,14 @@ func (r *ExtensionRuntime) storageRemove(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(true)
 }
 
-// ==================== Credentials API (Encrypted Storage) ====================
-
-// getCredentialsPath returns the path to the extension's encrypted credentials file
 func (r *ExtensionRuntime) getCredentialsPath() string {
 	return filepath.Join(r.dataDir, ".credentials.enc")
 }
 
-// getSaltPath returns the path to the extension's encryption salt file
 func (r *ExtensionRuntime) getSaltPath() string {
 	return filepath.Join(r.dataDir, ".cred_salt")
 }
 
-// getOrCreateSalt gets existing salt or creates a new random one
 func (r *ExtensionRuntime) getOrCreateSalt() ([]byte, error) {
 	saltPath := r.getSaltPath()
 
@@ -160,22 +148,17 @@ func (r *ExtensionRuntime) getOrCreateSalt() ([]byte, error) {
 	return salt, nil
 }
 
-// getEncryptionKey derives an encryption key from extension ID + random salt
 func (r *ExtensionRuntime) getEncryptionKey() ([]byte, error) {
-	// Get or create per-installation random salt
 	salt, err := r.getOrCreateSalt()
 	if err != nil {
 		return nil, err
 	}
 
-	// Combine extension ID + random salt for key derivation
-	// This makes each installation unique, preventing mass decryption attacks
 	combined := append([]byte(r.extensionID), salt...)
 	hash := sha256.Sum256(combined)
 	return hash[:], nil
 }
 
-// loadCredentials loads and decrypts credentials from disk
 func (r *ExtensionRuntime) loadCredentials() (map[string]interface{}, error) {
 	credPath := r.getCredentialsPath()
 	data, err := os.ReadFile(credPath)
@@ -186,7 +169,6 @@ func (r *ExtensionRuntime) loadCredentials() (map[string]interface{}, error) {
 		return nil, err
 	}
 
-	// Decrypt the data
 	key, err := r.getEncryptionKey()
 	if err != nil {
 		return nil, fmt.Errorf("failed to get encryption key: %w", err)
@@ -204,7 +186,6 @@ func (r *ExtensionRuntime) loadCredentials() (map[string]interface{}, error) {
 	return creds, nil
 }
 
-// saveCredentials encrypts and saves credentials to disk
 func (r *ExtensionRuntime) saveCredentials(creds map[string]interface{}) error {
 	data, err := json.Marshal(creds)
 	if err != nil {
@@ -221,10 +202,9 @@ func (r *ExtensionRuntime) saveCredentials(creds map[string]interface{}) error {
 	}
 
 	credPath := r.getCredentialsPath()
-	return os.WriteFile(credPath, encrypted, 0600) // Restrictive permissions
+	return os.WriteFile(credPath, encrypted, 0600)
 }
 
-// credentialsStore stores an encrypted credential
 func (r *ExtensionRuntime) credentialsStore(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -260,7 +240,6 @@ func (r *ExtensionRuntime) credentialsStore(call goja.FunctionCall) goja.Value {
 	})
 }
 
-// credentialsGet retrieves a decrypted credential
 func (r *ExtensionRuntime) credentialsGet(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return goja.Undefined()
@@ -276,7 +255,6 @@ func (r *ExtensionRuntime) credentialsGet(call goja.FunctionCall) goja.Value {
 
 	value, exists := creds[key]
 	if !exists {
-		// Return default value if provided
 		if len(call.Arguments) > 1 {
 			return call.Arguments[1]
 		}
@@ -286,7 +264,6 @@ func (r *ExtensionRuntime) credentialsGet(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(value)
 }
 
-// credentialsRemove removes a credential
 func (r *ExtensionRuntime) credentialsRemove(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(false)
@@ -310,7 +287,6 @@ func (r *ExtensionRuntime) credentialsRemove(call goja.FunctionCall) goja.Value
 	return r.vm.ToValue(true)
 }
 
-// credentialsHas checks if a credential exists
 func (r *ExtensionRuntime) credentialsHas(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue(false)
@@ -327,9 +303,6 @@ func (r *ExtensionRuntime) credentialsHas(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(exists)
 }
 
-// ==================== Crypto Utilities ====================
-
-// encryptAES encrypts data using AES-GCM
 func encryptAES(plaintext []byte, key []byte) ([]byte, error) {
 	block, err := aes.NewCipher(key)
 	if err != nil {
@@ -350,7 +323,6 @@ func encryptAES(plaintext []byte, key []byte) ([]byte, error) {
 	return ciphertext, nil
 }
 
-// decryptAES decrypts data using AES-GCM
 func decryptAES(ciphertext []byte, key []byte) ([]byte, error) {
 	block, err := aes.NewCipher(key)
 	if err != nil {

go_backend/extension_runtime_utils.go

@@ -19,7 +19,6 @@ import (
 
 // ==================== Utility Functions ====================
 
-// base64Encode encodes a string to base64
 func (r *ExtensionRuntime) base64Encode(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -28,7 +27,6 @@ func (r *ExtensionRuntime) base64Encode(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(base64.StdEncoding.EncodeToString([]byte(input)))
 }
 
-// base64Decode decodes a base64 string
 func (r *ExtensionRuntime) base64Decode(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -41,7 +39,6 @@ func (r *ExtensionRuntime) base64Decode(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(string(decoded))
 }
 
-// md5Hash computes MD5 hash of a string
 func (r *ExtensionRuntime) md5Hash(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -51,7 +48,6 @@ func (r *ExtensionRuntime) md5Hash(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(hex.EncodeToString(hash[:]))
 }
 
-// sha256Hash computes SHA256 hash of a string
 func (r *ExtensionRuntime) sha256Hash(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -61,7 +57,6 @@ func (r *ExtensionRuntime) sha256Hash(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(hex.EncodeToString(hash[:]))
 }
 
-// hmacSHA256 computes HMAC-SHA256 of a message with a key
 func (r *ExtensionRuntime) hmacSHA256(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue("")
@@ -74,7 +69,6 @@ func (r *ExtensionRuntime) hmacSHA256(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(hex.EncodeToString(mac.Sum(nil)))
 }
 
-// hmacSHA256Base64 computes HMAC-SHA256 and returns base64 encoded result
 func (r *ExtensionRuntime) hmacSHA256Base64(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue("")
@@ -87,9 +81,6 @@ func (r *ExtensionRuntime) hmacSHA256Base64(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(base64.StdEncoding.EncodeToString(mac.Sum(nil)))
 }
 
-// hmacSHA1 computes HMAC-SHA1 of a message with a key (for TOTP)
-// Arguments: message (string or array of bytes), key (string or array of bytes)
-// Returns: array of bytes (for TOTP dynamic truncation)
 func (r *ExtensionRuntime) hmacSHA1(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue([]byte{})
@@ -142,7 +133,6 @@ func (r *ExtensionRuntime) hmacSHA1(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(jsArray)
 }
 
-// parseJSON parses a JSON string
 func (r *ExtensionRuntime) parseJSON(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return goja.Undefined()
@@ -158,7 +148,6 @@ func (r *ExtensionRuntime) parseJSON(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(result)
 }
 
-// stringifyJSON converts a value to JSON string
 func (r *ExtensionRuntime) stringifyJSON(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -174,9 +163,6 @@ func (r *ExtensionRuntime) stringifyJSON(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(string(data))
 }
 
-// ==================== Crypto Utilities for Extensions ====================
-
-// cryptoEncrypt encrypts a string using AES-GCM (for extension use)
 func (r *ExtensionRuntime) cryptoEncrypt(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -188,7 +174,6 @@ func (r *ExtensionRuntime) cryptoEncrypt(call goja.FunctionCall) goja.Value {
 	plaintext := call.Arguments[0].String()
 	keyStr := call.Arguments[1].String()
 
-	// Derive 32-byte key from provided key string
 	keyHash := sha256.Sum256([]byte(keyStr))
 
 	encrypted, err := encryptAES([]byte(plaintext), keyHash[:])
@@ -205,7 +190,6 @@ func (r *ExtensionRuntime) cryptoEncrypt(call goja.FunctionCall) goja.Value {
 	})
 }
 
-// cryptoDecrypt decrypts a string using AES-GCM (for extension use)
 func (r *ExtensionRuntime) cryptoDecrypt(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 2 {
 		return r.vm.ToValue(map[string]interface{}{
@@ -225,14 +209,13 @@ func (r *ExtensionRuntime) cryptoDecrypt(call goja.FunctionCall) goja.Value {
 		})
 	}
 
-	// Derive 32-byte key from provided key string
 	keyHash := sha256.Sum256([]byte(keyStr))
 
 	decrypted, err := decryptAES(ciphertext, keyHash[:])
 	if err != nil {
 		return r.vm.ToValue(map[string]interface{}{
 			"success": false,
-			"error":   err.Error(),
+			"error":   "invalid base64 ciphertext",
 		})
 	}
 
@@ -242,9 +225,8 @@ func (r *ExtensionRuntime) cryptoDecrypt(call goja.FunctionCall) goja.Value {
 	})
 }
 
-// cryptoGenerateKey generates a random encryption key
 func (r *ExtensionRuntime) cryptoGenerateKey(call goja.FunctionCall) goja.Value {
-	length := 32 // Default 256-bit key
+	length := 32
 	if len(call.Arguments) > 0 && !goja.IsUndefined(call.Arguments[0]) {
 		if l, ok := call.Arguments[0].Export().(float64); ok {
 			length = int(l)
@@ -266,13 +248,10 @@ func (r *ExtensionRuntime) cryptoGenerateKey(call goja.FunctionCall) goja.Value
 	})
 }
 
-// randomUserAgent returns a random Chrome User-Agent string
 func (r *ExtensionRuntime) randomUserAgent(call goja.FunctionCall) goja.Value {
 	return r.vm.ToValue(getRandomUserAgent())
 }
 
-// ==================== Logging Functions ====================
-
 func (r *ExtensionRuntime) logDebug(call goja.FunctionCall) goja.Value {
 	msg := r.formatLogArgs(call.Arguments)
 	GoLog("[Extension:%s:DEBUG] %s\n", r.extensionID, msg)
@@ -305,8 +284,6 @@ func (r *ExtensionRuntime) formatLogArgs(args []goja.Value) string {
 	return strings.Join(parts, " ")
 }
 
-// ==================== Go Backend Wrappers ====================
-
 func (r *ExtensionRuntime) sanitizeFilenameWrapper(call goja.FunctionCall) goja.Value {
 	if len(call.Arguments) < 1 {
 		return r.vm.ToValue("")
@@ -315,7 +292,6 @@ func (r *ExtensionRuntime) sanitizeFilenameWrapper(call goja.FunctionCall) goja.
 	return r.vm.ToValue(sanitizeFilename(input))
 }
 
-// RegisterGoBackendAPIs adds more Go backend functions to the VM
 func (r *ExtensionRuntime) RegisterGoBackendAPIs(vm *goja.Runtime) {
 	gobackendObj := vm.Get("gobackend")
 	if gobackendObj == nil || goja.IsUndefined(gobackendObj) {
@@ -325,7 +301,6 @@ func (r *ExtensionRuntime) RegisterGoBackendAPIs(vm *goja.Runtime) {
 
 	obj := gobackendObj.(*goja.Object)
 
-	// Expose sanitizeFilename
 	obj.Set("sanitizeFilename", func(call goja.FunctionCall) goja.Value {
 		if len(call.Arguments) < 1 {
 			return vm.ToValue("")
@@ -333,7 +308,6 @@ func (r *ExtensionRuntime) RegisterGoBackendAPIs(vm *goja.Runtime) {
 		return vm.ToValue(sanitizeFilename(call.Arguments[0].String()))
 	})
 
-	// Expose getAudioQuality
 	obj.Set("getAudioQuality", func(call goja.FunctionCall) goja.Value {
 		if len(call.Arguments) < 1 {
 			return vm.ToValue(map[string]interface{}{
@@ -356,7 +330,6 @@ func (r *ExtensionRuntime) RegisterGoBackendAPIs(vm *goja.Runtime) {
 		})
 	})
 
-	// Expose buildFilename
 	obj.Set("buildFilename", func(call goja.FunctionCall) goja.Value {
 		if len(call.Arguments) < 2 {
 			return vm.ToValue("")
@@ -373,7 +346,6 @@ func (r *ExtensionRuntime) RegisterGoBackendAPIs(vm *goja.Runtime) {
 		return vm.ToValue(buildFilenameFromTemplate(template, metadata))
 	})
 
-	// Expose getLocalTime - returns device local time info
 	obj.Set("getLocalTime", func(call goja.FunctionCall) goja.Value {
 		now := time.Now()
 		_, offsetSeconds := now.Zone()

go_backend/extension_settings.go

@@ -9,20 +9,17 @@ import (
 	"sync"
 )
 
-// ExtensionSettingsStore manages settings for all extensions
 type ExtensionSettingsStore struct {
 	mu       sync.RWMutex
 	dataDir  string
 	settings map[string]map[string]interface{} // extensionID -> settings
 }
 
-// Global settings store
 var (
 	globalSettingsStore     *ExtensionSettingsStore
 	globalSettingsStoreOnce sync.Once
 )
 
-// GetExtensionSettingsStore returns the global settings store
 func GetExtensionSettingsStore() *ExtensionSettingsStore {
 	globalSettingsStoreOnce.Do(func() {
 		globalSettingsStore = &ExtensionSettingsStore{
@@ -32,7 +29,6 @@ func GetExtensionSettingsStore() *ExtensionSettingsStore {
 	return globalSettingsStore
 }
 
-// SetDataDir sets the data directory for settings storage
 func (s *ExtensionSettingsStore) SetDataDir(dataDir string) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -45,12 +41,10 @@ func (s *ExtensionSettingsStore) SetDataDir(dataDir string) error {
 	return s.loadAllSettings()
 }
 
-// getSettingsPath returns the path to an extension's settings file
 func (s *ExtensionSettingsStore) getSettingsPath(extensionID string) string {
 	return filepath.Join(s.dataDir, extensionID, "settings.json")
 }
 
-// loadAllSettings loads settings for all extensions from disk
 func (s *ExtensionSettingsStore) loadAllSettings() error {
 	entries, err := os.ReadDir(s.dataDir)
 	if err != nil {
@@ -75,7 +69,6 @@ func (s *ExtensionSettingsStore) loadAllSettings() error {
 	return nil
 }
 
-// loadSettings loads settings for a specific extension
 func (s *ExtensionSettingsStore) loadSettings(extensionID string) (map[string]interface{}, error) {
 	settingsPath := s.getSettingsPath(extensionID)
 	data, err := os.ReadFile(settingsPath)
@@ -94,7 +87,6 @@ func (s *ExtensionSettingsStore) loadSettings(extensionID string) (map[string]in
 	return settings, nil
 }
 
-// saveSettings saves settings for a specific extension
 func (s *ExtensionSettingsStore) saveSettings(extensionID string, settings map[string]interface{}) error {
 	settingsPath := s.getSettingsPath(extensionID)
 
@@ -111,8 +103,6 @@ func (s *ExtensionSettingsStore) saveSettings(extensionID string, settings map[s
 	return os.WriteFile(settingsPath, data, 0644)
 }
 
-// Get retrieves a setting value for an extension
-// Returns error if extension or key not found (gomobile compatible)
 func (s *ExtensionSettingsStore) Get(extensionID, key string) (interface{}, error) {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
@@ -129,7 +119,6 @@ func (s *ExtensionSettingsStore) Get(extensionID, key string) (interface{}, erro
 	return value, nil
 }
 
-// GetAll retrieves all settings for an extension
 func (s *ExtensionSettingsStore) GetAll(extensionID string) map[string]interface{} {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
@@ -139,7 +128,6 @@ func (s *ExtensionSettingsStore) GetAll(extensionID string) map[string]interface
 		return make(map[string]interface{})
 	}
 
-	// Return a copy
 	result := make(map[string]interface{})
 	for k, v := range extSettings {
 		result[k] = v
@@ -147,7 +135,6 @@ func (s *ExtensionSettingsStore) GetAll(extensionID string) map[string]interface
 	return result
 }
 
-// Set stores a setting value for an extension
 func (s *ExtensionSettingsStore) Set(extensionID, key string, value interface{}) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -161,18 +148,15 @@ func (s *ExtensionSettingsStore) Set(extensionID, key string, value interface{})
 	return s.saveSettings(extensionID, s.settings[extensionID])
 }
 
-// SetAll stores all settings for an extension
 func (s *ExtensionSettingsStore) SetAll(extensionID string, settings map[string]interface{}) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
 
 	s.settings[extensionID] = settings
 
-	// Persist to disk
 	return s.saveSettings(extensionID, settings)
 }
 
-// Remove removes a setting for an extension
 func (s *ExtensionSettingsStore) Remove(extensionID, key string) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -184,11 +168,9 @@ func (s *ExtensionSettingsStore) Remove(extensionID, key string) error {
 
 	delete(extSettings, key)
 
-	// Persist to disk
 	return s.saveSettings(extensionID, extSettings)
 }
 
-// RemoveAll removes all settings for an extension
 func (s *ExtensionSettingsStore) RemoveAll(extensionID string) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -203,7 +185,6 @@ func (s *ExtensionSettingsStore) RemoveAll(extensionID string) error {
 	return nil
 }
 
-// GetAllExtensionSettings returns settings for all extensions as JSON
 func (s *ExtensionSettingsStore) GetAllExtensionSettingsJSON() (string, error) {
 	s.mu.RLock()
 	defer s.mu.RUnlock()

go_backend/extension_store.go

@@ -5,13 +5,13 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
 	"os"
 	"path/filepath"
 	"sync"
 	"time"
 )
 
-// Extension categories
 const (
 	CategoryMetadata    = "metadata"
 	CategoryDownload    = "download"
@@ -20,28 +20,26 @@ const (
 	CategoryIntegration = "integration"
 )
 
-// StoreExtension represents an extension in the store
 type StoreExtension struct {
-	ID            string   `json:"id"`
-	Name          string   `json:"name"`
-	DisplayName   string   `json:"display_name,omitempty"`
-	Version       string   `json:"version"`
-	Author        string   `json:"author"`
-	Description   string   `json:"description"`
-	DownloadURL   string   `json:"download_url,omitempty"`
-	IconURL       string   `json:"icon_url,omitempty"`
-	Category      string   `json:"category"`
-	Tags          []string `json:"tags,omitempty"`
-	Downloads     int      `json:"downloads"`
-	UpdatedAt     string   `json:"updated_at"`
-	MinAppVersion string   `json:"min_app_version,omitempty"`
-	DisplayNameAlt   string `json:"displayName,omitempty"`
-	DownloadURLAlt   string `json:"downloadUrl,omitempty"`
-	IconURLAlt       string `json:"iconUrl,omitempty"`
-	MinAppVersionAlt string `json:"minAppVersion,omitempty"`
+	ID               string   `json:"id"`
+	Name             string   `json:"name"`
+	DisplayName      string   `json:"display_name,omitempty"`
+	Version          string   `json:"version"`
+	Author           string   `json:"author"`
+	Description      string   `json:"description"`
+	DownloadURL      string   `json:"download_url,omitempty"`
+	IconURL          string   `json:"icon_url,omitempty"`
+	Category         string   `json:"category"`
+	Tags             []string `json:"tags,omitempty"`
+	Downloads        int      `json:"downloads"`
+	UpdatedAt        string   `json:"updated_at"`
+	MinAppVersion    string   `json:"min_app_version,omitempty"`
+	DisplayNameAlt   string   `json:"displayName,omitempty"`
+	DownloadURLAlt   string   `json:"downloadUrl,omitempty"`
+	IconURLAlt       string   `json:"iconUrl,omitempty"`
+	MinAppVersionAlt string   `json:"minAppVersion,omitempty"`
 }
 
-// getDisplayName returns display name, falling back to name (private to avoid gomobile conflict)
 func (e *StoreExtension) getDisplayName() string {
 	if e.DisplayName != "" {
 		return e.DisplayName
@@ -52,7 +50,6 @@ func (e *StoreExtension) getDisplayName() string {
 	return e.Name
 }
 
-// getDownloadURL returns download URL from either field (private to avoid gomobile conflict)
 func (e *StoreExtension) getDownloadURL() string {
 	if e.DownloadURL != "" {
 		return e.DownloadURL
@@ -60,7 +57,6 @@ func (e *StoreExtension) getDownloadURL() string {
 	return e.DownloadURLAlt
 }
 
-// getIconURL returns icon URL from either field (private to avoid gomobile conflict)
 func (e *StoreExtension) getIconURL() string {
 	if e.IconURL != "" {
 		return e.IconURL
@@ -68,7 +64,6 @@ func (e *StoreExtension) getIconURL() string {
 	return e.IconURLAlt
 }
 
-// getMinAppVersion returns min app version from either field (private to avoid gomobile conflict)
 func (e *StoreExtension) getMinAppVersion() string {
 	if e.MinAppVersion != "" {
 		return e.MinAppVersion
@@ -76,7 +71,6 @@ func (e *StoreExtension) getMinAppVersion() string {
 	return e.MinAppVersionAlt
 }
 
-// StoreRegistry represents the extension registry
 type StoreRegistry struct {
 	Version    int              `json:"version"`
 	UpdatedAt  string           `json:"updated_at"`
@@ -103,7 +97,6 @@ type StoreExtensionResponse struct {
 	HasUpdate        bool     `json:"has_update"`
 }
 
-// ToResponse converts StoreExtension to normalized response
 func (e *StoreExtension) ToResponse() StoreExtensionResponse {
 	return StoreExtensionResponse{
 		ID:            e.ID,
@@ -122,7 +115,6 @@ func (e *StoreExtension) ToResponse() StoreExtensionResponse {
 	}
 }
 
-// ExtensionStore manages the extension store
 type ExtensionStore struct {
 	registryURL string
 	cacheDir    string
@@ -143,7 +135,6 @@ const (
 	cacheFileName      = "store_cache.json"
 )
 
-// InitExtensionStore initializes the extension store
 func InitExtensionStore(cacheDir string) *ExtensionStore {
 	extensionStoreMu.Lock()
 	defer extensionStoreMu.Unlock()
@@ -154,20 +145,17 @@ func InitExtensionStore(cacheDir string) *ExtensionStore {
 			cacheDir:    cacheDir,
 			cacheTTL:    cacheTTL,
 		}
-		// Try to load from disk cache
 		extensionStore.loadDiskCache()
 	}
 	return extensionStore
 }
 
-// GetExtensionStore returns the singleton store instance
 func GetExtensionStore() *ExtensionStore {
 	extensionStoreMu.Lock()
 	defer extensionStoreMu.Unlock()
 	return extensionStore
 }
 
-// loadDiskCache loads cached registry from disk
 func (s *ExtensionStore) loadDiskCache() {
 	if s.cacheDir == "" {
 		return
@@ -193,7 +181,6 @@ func (s *ExtensionStore) loadDiskCache() {
 	LogDebug("ExtensionStore", "Loaded %d extensions from disk cache", len(s.cache.Extensions))
 }
 
-// saveDiskCache saves registry to disk cache
 func (s *ExtensionStore) saveDiskCache() {
 	if s.cacheDir == "" || s.cache == nil {
 		return
@@ -216,23 +203,24 @@ func (s *ExtensionStore) saveDiskCache() {
 	os.WriteFile(cachePath, data, 0644)
 }
 
-// FetchRegistry fetches the extension registry from GitHub
 func (s *ExtensionStore) FetchRegistry(forceRefresh bool) (*StoreRegistry, error) {
 	s.cacheMu.Lock()
 	defer s.cacheMu.Unlock()
 
-	// Return cached if valid and not forcing refresh
 	if !forceRefresh && s.cache != nil && time.Since(s.cacheTime) < s.cacheTTL {
 		LogDebug("ExtensionStore", "Using cached registry (%d extensions)", len(s.cache.Extensions))
 		return s.cache, nil
 	}
 
+	if err := requireHTTPSURL(s.registryURL, "registry"); err != nil {
+		return nil, err
+	}
+
 	LogInfo("ExtensionStore", "Fetching registry from %s", s.registryURL)
 
 	client := &http.Client{Timeout: 30 * time.Second}
 	resp, err := client.Get(s.registryURL)
 	if err != nil {
-		// Return cached data if available on network error
 		if s.cache != nil {
 			LogWarn("ExtensionStore", "Network error, using cached registry: %v", err)
 			return s.cache, nil
@@ -267,7 +255,6 @@ func (s *ExtensionStore) FetchRegistry(forceRefresh bool) (*StoreRegistry, error
 	return &registry, nil
 }
 
-// GetExtensionsWithStatus returns extensions with installation status
 func (s *ExtensionStore) GetExtensionsWithStatus() ([]StoreExtensionResponse, error) {
 	registry, err := s.FetchRegistry(false)
 	if err != nil {
@@ -299,7 +286,6 @@ func (s *ExtensionStore) GetExtensionsWithStatus() ([]StoreExtensionResponse, er
 	return result, nil
 }
 
-// DownloadExtension downloads an extension package to the specified path
 func (s *ExtensionStore) DownloadExtension(extensionID string, destPath string) error {
 	registry, err := s.FetchRegistry(false)
 	if err != nil {
@@ -318,6 +304,10 @@ func (s *ExtensionStore) DownloadExtension(extensionID string, destPath string)
 		return fmt.Errorf("extension %s not found in store", extensionID)
 	}
 
+	if err := requireHTTPSURL(ext.getDownloadURL(), "extension download"); err != nil {
+		return err
+	}
+
 	LogInfo("ExtensionStore", "Downloading %s from %s", ext.getDisplayName(), ext.getDownloadURL())
 
 	client := &http.Client{Timeout: 5 * time.Minute}
@@ -347,7 +337,20 @@ func (s *ExtensionStore) DownloadExtension(extensionID string, destPath string)
 	return nil
 }
 
-// GetCategories returns all available categories
+func requireHTTPSURL(rawURL string, context string) error {
+	if rawURL == "" {
+		return fmt.Errorf("%s URL is empty", context)
+	}
+	parsed, err := url.Parse(rawURL)
+	if err != nil || parsed.Host == "" {
+		return fmt.Errorf("%s URL is invalid: %s", context, rawURL)
+	}
+	if parsed.Scheme != "https" {
+		return fmt.Errorf("%s URL must use https: %s", context, rawURL)
+	}
+	return nil
+}
+
 func (s *ExtensionStore) GetCategories() []string {
 	return []string{
 		CategoryMetadata,
@@ -358,7 +361,6 @@ func (s *ExtensionStore) GetCategories() []string {
 	}
 }
 
-// SearchExtensions searches extensions by query
 func (s *ExtensionStore) SearchExtensions(query string, category string) ([]StoreExtensionResponse, error) {
 	extensions, err := s.GetExtensionsWithStatus()
 	if err != nil {
@@ -404,7 +406,6 @@ func (s *ExtensionStore) SearchExtensions(query string, category string) ([]Stor
 	return result, nil
 }
 
-// ClearCache clears the in-memory and disk cache
 func (s *ExtensionStore) ClearCache() {
 	s.cacheMu.Lock()
 	defer s.cacheMu.Unlock()

go_backend/extension_test.go

@@ -112,7 +112,6 @@ func TestExtensionRuntime_NetworkSandbox(t *testing.T) {
 
 	runtime := NewExtensionRuntime(ext)
 
-	// Test allowed domains
 	if err := runtime.validateDomain("https://api.allowed.com/path"); err != nil {
 		t.Errorf("Expected api.allowed.com to be allowed, got error: %v", err)
 	}
@@ -121,7 +120,6 @@ func TestExtensionRuntime_NetworkSandbox(t *testing.T) {
 		t.Errorf("Expected sub.wildcard.com to be allowed (wildcard), got error: %v", err)
 	}
 
-	// Test blocked domains
 	if err := runtime.validateDomain("https://blocked.com/path"); err == nil {
 		t.Error("Expected blocked.com to be denied")
 	}
@@ -139,7 +137,7 @@ func TestExtensionRuntime_FileSandbox(t *testing.T) {
 		Manifest: &ExtensionManifest{
 			Name: "test-ext",
 			Permissions: ExtensionPermissions{
-				File: true, // Enable file permission for test
+				File: true,
 			},
 		},
 		DataDir: tempDir,
@@ -147,7 +145,6 @@ func TestExtensionRuntime_FileSandbox(t *testing.T) {
 
 	runtime := NewExtensionRuntime(ext)
 
-	// Test valid path within sandbox
 	validPath, err := runtime.validatePath("test.txt")
 	if err != nil {
 		t.Errorf("Expected relative path to be valid, got error: %v", err)
@@ -156,13 +153,11 @@ func TestExtensionRuntime_FileSandbox(t *testing.T) {
 		t.Error("Expected non-empty path")
 	}
 
-	// Test path traversal attack
 	_, err = runtime.validatePath("../../../etc/passwd")
 	if err == nil {
 		t.Error("Expected path traversal to be blocked")
 	}
 
-	// Test nested path within sandbox (should be allowed)
 	nestedPath, err := runtime.validatePath("subdir/file.txt")
 	if err != nil {
 		t.Errorf("Expected nested path to be valid, got error: %v", err)
@@ -171,26 +166,23 @@ func TestExtensionRuntime_FileSandbox(t *testing.T) {
 		t.Error("Expected non-empty nested path")
 	}
 
-	// Test absolute path should be blocked (security fix)
-	// Use platform-appropriate absolute path
 	var absPath string
 	if filepath.IsAbs("C:\\Windows\\System32") {
-		absPath = "C:\\Windows\\System32\\test.txt" // Windows
+		absPath = "C:\\Windows\\System32\\test.txt"
 	} else {
-		absPath = "/etc/passwd" // Unix
+		absPath = "/etc/passwd"
 	}
 	_, err = runtime.validatePath(absPath)
 	if err == nil {
 		t.Error("Expected absolute path to be blocked")
 	}
 
-	// Test that extension without file permission is blocked
 	extNoFile := &LoadedExtension{
 		ID: "test-ext-no-file",
 		Manifest: &ExtensionManifest{
 			Name: "test-ext-no-file",
 			Permissions: ExtensionPermissions{
-				File: false, // No file permission
+				File: false,
 			},
 		},
 		DataDir: tempDir,
@@ -215,7 +207,6 @@ func TestExtensionRuntime_UtilityFunctions(t *testing.T) {
 	vm := goja.New()
 	runtime.RegisterAPIs(vm)
 
-	// Test base64 encode/decode
 	result, err := vm.RunString(`utils.base64Encode("hello")`)
 	if err != nil {
 		t.Fatalf("base64Encode failed: %v", err)
@@ -232,7 +223,6 @@ func TestExtensionRuntime_UtilityFunctions(t *testing.T) {
 		t.Errorf("Expected 'hello', got '%s'", result.String())
 	}
 
-	// Test MD5
 	result, err = vm.RunString(`utils.md5("hello")`)
 	if err != nil {
 		t.Fatalf("md5 failed: %v", err)
@@ -241,7 +231,6 @@ func TestExtensionRuntime_UtilityFunctions(t *testing.T) {
 		t.Errorf("Expected '5d41402abc4b2a76b9719d911017c592', got '%s'", result.String())
 	}
 
-	// Test JSON parse/stringify
 	result, err = vm.RunString(`utils.stringifyJSON({name: "test", value: 123})`)
 	if err != nil {
 		t.Fatalf("stringifyJSON failed: %v", err)
@@ -267,7 +256,6 @@ func TestExtensionRuntime_SSRFProtection(t *testing.T) {
 
 	runtime := NewExtensionRuntime(ext)
 
-	// Test that private IPs are blocked (SSRF protection)
 	privateIPs := []string{
 		"http://localhost/admin",
 		"http://127.0.0.1/admin",
@@ -285,7 +273,6 @@ func TestExtensionRuntime_SSRFProtection(t *testing.T) {
 		}
 	}
 
-	// Test that allowed public domain still works
 	if err := runtime.validateDomain("https://api.example.com/path"); err != nil {
 		t.Errorf("Expected api.example.com to be allowed, got error: %v", err)
 	}
@@ -296,7 +283,6 @@ func TestIsPrivateIP(t *testing.T) {
 		host     string
 		expected bool
 	}{
-		// Private IPs should be blocked
 		{"localhost", true},
 		{"127.0.0.1", true},
 		{"127.0.0.2", true},
@@ -306,18 +292,17 @@ func TestIsPrivateIP(t *testing.T) {
 		{"172.31.255.255", true},
 		{"192.168.0.1", true},
 		{"192.168.255.255", true},
-		{"169.254.169.254", true}, // AWS metadata
+		{"169.254.169.254", true},
 		{"router.local", true},
 		{"mydevice.local", true},
 
-		// Public IPs should be allowed
 		{"8.8.8.8", false},
 		{"1.1.1.1", false},
 		{"api.example.com", false},
 		{"google.com", false},
-		{"172.15.0.1", false},  // Just outside 172.16-31 range
-		{"172.32.0.1", false},  // Just outside 172.16-31 range
-		{"192.167.0.1", false}, // Not 192.168.x.x
+		{"172.15.0.1", false},
+		{"172.32.0.1", false},
+		{"192.167.0.1", false},
 	}
 
 	for _, tt := range tests {

go_backend/extension_timeout.go

@@ -4,13 +4,13 @@ package gobackend
 import (
 	"context"
 	"fmt"
+	"runtime/debug"
 	"sync"
 	"time"
 
 	"github.com/dop251/goja"
 )
 
-// JSExecutionError represents an error during JS execution
 type JSExecutionError struct {
 	Message   string
 	IsTimeout bool
@@ -20,8 +20,6 @@ func (e *JSExecutionError) Error() string {
 	return e.Message
 }
 
-// RunWithTimeout executes JavaScript code with a timeout
-// Returns the result value and any error (including timeout)
 func RunWithTimeout(vm *goja.Runtime, script string, timeout time.Duration) (goja.Value, error) {
 	if timeout <= 0 {
 		timeout = DefaultJSTimeout
@@ -30,22 +28,18 @@ func RunWithTimeout(vm *goja.Runtime, script string, timeout time.Duration) (goj
 	ctx, cancel := context.WithTimeout(context.Background(), timeout)
 	defer cancel()
 
-	// Channel to receive result
 	type result struct {
 		value goja.Value
 		err   error
 	}
 	resultCh := make(chan result, 1)
 
-	// Track if we've interrupted
 	var interrupted bool
 	var interruptMu sync.Mutex
 
-	// Run script in goroutine
 	go func() {
 		defer func() {
 			if r := recover(); r != nil {
-				// Check if this was our interrupt
 				interruptMu.Lock()
 				wasInterrupted := interrupted
 				interruptMu.Unlock()
@@ -56,6 +50,7 @@ func RunWithTimeout(vm *goja.Runtime, script string, timeout time.Duration) (goj
 						IsTimeout: true,
 					}}
 				} else {
+					GoLog("[ExtensionRuntime] panic during JS execution: %v\n%s\n", r, string(debug.Stack()))
 					resultCh <- result{nil, fmt.Errorf("panic during execution: %v", r)}
 				}
 			}
@@ -65,22 +60,18 @@ func RunWithTimeout(vm *goja.Runtime, script string, timeout time.Duration) (goj
 		resultCh <- result{val, err}
 	}()
 
-	// Wait for result or timeout
 	select {
 	case res := <-resultCh:
 		return res.value, res.err
 	case <-ctx.Done():
-		// Timeout - interrupt the VM
 		interruptMu.Lock()
 		interrupted = true
 		interruptMu.Unlock()
 
 		vm.Interrupt("execution timeout")
 
-		// Wait a bit for the goroutine to finish
 		select {
 		case res := <-resultCh:
-			// If we got a result after interrupt, it might be the timeout error
 			if res.err != nil {
 				return nil, res.err
 			}
@@ -89,7 +80,6 @@ func RunWithTimeout(vm *goja.Runtime, script string, timeout time.Duration) (goj
 				IsTimeout: true,
 			}
 		case <-time.After(1 * time.Second):
-			// Force return timeout error
 			return nil, &JSExecutionError{
 				Message:   "execution timeout exceeded (force)",
 				IsTimeout: true,
@@ -109,7 +99,6 @@ func RunWithTimeoutAndRecover(vm *goja.Runtime, script string, timeout time.Dura
 	return result, err
 }
 
-// IsTimeoutError checks if an error is a timeout error
 func IsTimeoutError(err error) bool {
 	if jsErr, ok := err.(*JSExecutionError); ok {
 		return jsErr.IsTimeout

go_backend/filename.go

@@ -3,28 +3,35 @@ package gobackend
 import (
 	"fmt"
 	"regexp"
+	"strconv"
 	"strings"
+	"time"
 )
 
-var invalidChars = regexp.MustCompile(`[<>:"/\\|?*\x00-\x1f]`)
+var (
+	invalidChars                   = regexp.MustCompile(`[<>:"/\\|?*\x00-\x1f]`)
+	multiUnderscore                = regexp.MustCompile(`_+`)
+	formattedNumberPlaceholderExpr = regexp.MustCompile(`\{(track|disc):([0-9]+)\}`)
+	dateFormatPlaceholderExpr      = regexp.MustCompile(`\{date:([^{}]+)\}`)
+	yearPattern                    = regexp.MustCompile(`\d{4}`)
+)
 
 func sanitizeFilename(filename string) string {
 	sanitized := invalidChars.ReplaceAllString(filename, "_")
-	
+
 	sanitized = strings.TrimSpace(sanitized)
 	sanitized = strings.Trim(sanitized, ".")
-	
-	multiUnderscore := regexp.MustCompile(`_+`)
+
 	sanitized = multiUnderscore.ReplaceAllString(sanitized, "_")
-	
+
 	if len(sanitized) > 200 {
 		sanitized = sanitized[:200]
 	}
-	
+
 	if sanitized == "" {
 		sanitized = "untitled"
 	}
-	
+
 	return sanitized
 }
 
@@ -32,45 +39,120 @@ func buildFilenameFromTemplate(template string, metadata map[string]interface{})
 	if template == "" {
 		template = "{artist} - {title}"
 	}
-	
-	result := template
-	
-	placeholders := map[string]string{
-		"{title}":  getString(metadata, "title"),
-		"{artist}": getString(metadata, "artist"),
-		"{album}":  getString(metadata, "album"),
-		"{track}":  formatTrackNumber(getInt(metadata, "track")),
-		"{year}":   getString(metadata, "year"),
-		"{disc}":   formatDiscNumber(getInt(metadata, "disc")),
+
+	result := replaceFormattedNumberPlaceholders(template, metadata)
+	result = replaceDateFormatPlaceholders(result, metadata)
+
+	dateValue := getDateValue(metadata)
+	yearValue := getString(metadata, "year")
+	if yearValue == "" {
+		yearValue = extractYear(dateValue)
 	}
-	
+
+	placeholders := map[string]string{
+		"{title}":     getString(metadata, "title"),
+		"{artist}":    getString(metadata, "artist"),
+		"{album}":     getString(metadata, "album"),
+		"{track}":     formatTrackNumber(getInt(metadata, "track")),
+		"{track_raw}": formatRawNumber(getInt(metadata, "track")),
+		"{year}":      yearValue,
+		"{date}":      dateValue,
+		"{disc}":      formatDiscNumber(getInt(metadata, "disc")),
+		"{disc_raw}":  formatRawNumber(getInt(metadata, "disc")),
+	}
+
 	for placeholder, value := range placeholders {
 		result = strings.ReplaceAll(result, placeholder, value)
 	}
-	
+
 	return result
 }
 
+func replaceFormattedNumberPlaceholders(template string, metadata map[string]interface{}) string {
+	return formattedNumberPlaceholderExpr.ReplaceAllStringFunc(template, func(match string) string {
+		parts := formattedNumberPlaceholderExpr.FindStringSubmatch(match)
+		if len(parts) != 3 {
+			return ""
+		}
+
+		number := getInt(metadata, parts[1])
+		width, err := strconv.Atoi(parts[2])
+		if err != nil {
+			return ""
+		}
+
+		return formatNumberWithWidth(number, width)
+	})
+}
+
+func replaceDateFormatPlaceholders(template string, metadata map[string]interface{}) string {
+	return dateFormatPlaceholderExpr.ReplaceAllStringFunc(template, func(match string) string {
+		parts := dateFormatPlaceholderExpr.FindStringSubmatch(match)
+		if len(parts) != 2 {
+			return ""
+		}
+
+		return formatDateWithPattern(getDateValue(metadata), parts[1])
+	})
+}
+
+func getDateValue(metadata map[string]interface{}) string {
+	date := getString(metadata, "date")
+	if date != "" {
+		return date
+	}
+
+	releaseDate := getString(metadata, "release_date")
+	if releaseDate != "" {
+		return releaseDate
+	}
+
+	return getString(metadata, "year")
+}
+
 func getString(m map[string]interface{}, key string) string {
 	if v, ok := m[key]; ok {
-		if s, ok := v.(string); ok {
-			return strings.TrimSpace(s)
+		switch value := v.(type) {
+		case string:
+			return strings.TrimSpace(value)
+		case int:
+			return strconv.Itoa(value)
+		case int64:
+			return strconv.FormatInt(value, 10)
+		case float64:
+			return strconv.Itoa(int(value))
 		}
 	}
 	return ""
 }
 
 func getInt(m map[string]interface{}, key string) int {
-	if v, ok := m[key]; ok {
-		switch n := v.(type) {
-		case int:
-			return n
-		case int64:
-			return int(n)
-		case float64:
-			return int(n)
+	candidateKeys := []string{key}
+	switch key {
+	case "track":
+		candidateKeys = append(candidateKeys, "track_number")
+	case "disc":
+		candidateKeys = append(candidateKeys, "disc_number")
+	}
+
+	for _, candidate := range candidateKeys {
+		if v, ok := m[candidate]; ok {
+			switch n := v.(type) {
+			case int:
+				return n
+			case int64:
+				return int(n)
+			case float64:
+				return int(n)
+			case string:
+				parsed, err := strconv.Atoi(strings.TrimSpace(n))
+				if err == nil {
+					return parsed
+				}
+			}
 		}
 	}
+
 	return 0
 }
 
@@ -88,6 +170,129 @@ func formatDiscNumber(n int) string {
 	return fmt.Sprintf("%d", n)
 }
 
+func formatRawNumber(n int) string {
+	if n <= 0 {
+		return ""
+	}
+	return fmt.Sprintf("%d", n)
+}
+
+func formatNumberWithWidth(n int, width int) string {
+	if n <= 0 || width <= 0 {
+		return ""
+	}
+	if width <= 1 {
+		return formatRawNumber(n)
+	}
+	return fmt.Sprintf("%0*d", width, n)
+}
+
+func formatDateWithPattern(rawDate string, strftimePattern string) string {
+	if rawDate == "" || strftimePattern == "" {
+		return ""
+	}
+
+	parsedDate, ok := parseMetadataDate(rawDate)
+	if !ok {
+		return ""
+	}
+
+	goLayout := convertStrftimeToGoLayout(strftimePattern)
+	if goLayout == "" {
+		return ""
+	}
+
+	return parsedDate.Format(goLayout)
+}
+
+func parseMetadataDate(rawDate string) (time.Time, bool) {
+	clean := strings.TrimSpace(rawDate)
+	if clean == "" {
+		return time.Time{}, false
+	}
+
+	layouts := []string{
+		time.RFC3339Nano,
+		time.RFC3339,
+		"2006-01-02",
+		"2006-01",
+		"2006",
+		"2006/01/02",
+		"2006/01",
+		"2006.01.02",
+		"2006.01",
+	}
+
+	for _, layout := range layouts {
+		parsed, err := time.Parse(layout, clean)
+		if err == nil {
+			return parsed, true
+		}
+	}
+
+	if len(clean) >= 10 {
+		parsed, err := time.Parse("2006-01-02", clean[:10])
+		if err == nil {
+			return parsed, true
+		}
+	}
+
+	yearMatch := yearPattern.FindString(clean)
+	if yearMatch == "" {
+		return time.Time{}, false
+	}
+
+	year, err := strconv.Atoi(yearMatch)
+	if err != nil || year <= 0 {
+		return time.Time{}, false
+	}
+
+	return time.Date(year, time.January, 1, 0, 0, 0, 0, time.UTC), true
+}
+
+func convertStrftimeToGoLayout(pattern string) string {
+	if pattern == "" {
+		return ""
+	}
+
+	var builder strings.Builder
+	for i := 0; i < len(pattern); i++ {
+		ch := pattern[i]
+		if ch != '%' {
+			builder.WriteByte(ch)
+			continue
+		}
+
+		if i+1 >= len(pattern) {
+			builder.WriteByte('%')
+			break
+		}
+
+		i++
+		switch pattern[i] {
+		case 'Y':
+			builder.WriteString("2006")
+		case 'y':
+			builder.WriteString("06")
+		case 'm':
+			builder.WriteString("01")
+		case 'd':
+			builder.WriteString("02")
+		case 'b':
+			builder.WriteString("Jan")
+		case 'B':
+			builder.WriteString("January")
+		case '%':
+			builder.WriteByte('%')
+		default:
+			builder.WriteByte('%')
+			builder.WriteByte(pattern[i])
+		}
+	}
+
+	return builder.String()
+}
+
 func extractYear(date string) string {
 	if len(date) >= 4 {
 		return date[:4]

go_backend/filename_test.go

@@ -0,0 +1,85 @@
+package gobackend
+
+import "testing"
+
+func TestBuildFilenameFromTemplate_WithRawTrackAndDisc(t *testing.T) {
+	metadata := map[string]interface{}{
+		"title":  "Song Name",
+		"artist": "Artist Name",
+		"album":  "Album Name",
+		"track":  1,
+		"disc":   2,
+		"year":   "2025",
+	}
+
+	formatted := buildFilenameFromTemplate(
+		"{artist} - {track} - {track_raw} - d{disc} - d{disc_raw} - {title}",
+		metadata,
+	)
+
+	expected := "Artist Name - 01 - 1 - d2 - d2 - Song Name"
+	if formatted != expected {
+		t.Fatalf("expected %q, got %q", expected, formatted)
+	}
+}
+
+func TestBuildFilenameFromTemplate_RawPlaceholdersEmptyWhenZero(t *testing.T) {
+	metadata := map[string]interface{}{
+		"title":  "Song Name",
+		"artist": "Artist Name",
+		"track":  0,
+		"disc":   0,
+	}
+
+	formatted := buildFilenameFromTemplate("{track_raw}-{disc_raw}-{title}", metadata)
+	expected := "--Song Name"
+	if formatted != expected {
+		t.Fatalf("expected %q, got %q", expected, formatted)
+	}
+}
+
+func TestBuildFilenameFromTemplate_InlineNumberFormatting(t *testing.T) {
+	metadata := map[string]interface{}{
+		"track": 3,
+		"disc":  2,
+	}
+
+	formatted := buildFilenameFromTemplate("{track:1}-{track:02}-{disc:03}", metadata)
+	expected := "3-03-002"
+	if formatted != expected {
+		t.Fatalf("expected %q, got %q", expected, formatted)
+	}
+}
+
+func TestBuildFilenameFromTemplate_DateStrftimeFormatting(t *testing.T) {
+	metadata := map[string]interface{}{
+		"artist":       "Artist Name",
+		"title":        "Song Name",
+		"release_date": "2024-03-09",
+		"track_number": 7,
+		"disc_number":  1,
+	}
+
+	formatted := buildFilenameFromTemplate(
+		"{artist} - {track:02} - {title} - {date:%Y-%m-%d} - {year}",
+		metadata,
+	)
+	expected := "Artist Name - 07 - Song Name - 2024-03-09 - 2024"
+	if formatted != expected {
+		t.Fatalf("expected %q, got %q", expected, formatted)
+	}
+}
+
+func TestBuildFilenameFromTemplate_DateStrftimeFormattingWithYearOnly(t *testing.T) {
+	metadata := map[string]interface{}{
+		"artist": "Artist Name",
+		"title":  "Song Name",
+		"date":   "2019",
+	}
+
+	formatted := buildFilenameFromTemplate("{date:%Y}-{date:%m}-{date:%d}", metadata)
+	expected := "2019-01-01"
+	if formatted != expected {
+		t.Fatalf("expected %q, got %q", expected, formatted)
+	}
+}

go_backend/go.mod

@@ -1,17 +1,17 @@
 module github.com/zarz/spotiflac_android/go_backend
 
-go 1.24.0
+go 1.25.0
 
-toolchain go1.24.5
+toolchain go1.26.0
 
 require (
 	github.com/dop251/goja v0.0.0-20260106131823-651366fbe6e3
-	github.com/go-flac/flacpicture v0.3.0
-	github.com/go-flac/flacvorbis v0.2.0
-	github.com/go-flac/go-flac v1.0.0
+	github.com/go-flac/flacpicture/v2 v2.0.2
+	github.com/go-flac/flacvorbis/v2 v2.0.2
+	github.com/go-flac/go-flac/v2 v2.0.4
 	github.com/refraction-networking/utls v1.8.2
-	golang.org/x/mobile v0.0.0-20260120165949-40bd9ace6ce4
-	golang.org/x/net v0.49.0
+	golang.org/x/mobile v0.0.0-20260209203831-923679eb55af
+	golang.org/x/net v0.50.0
 )
 
 require (
@@ -20,10 +20,10 @@ require (
 	github.com/go-sourcemap/sourcemap v2.1.3+incompatible // indirect
 	github.com/google/pprof v0.0.0-20230207041349-798e818bf904 // indirect
 	github.com/klauspost/compress v1.17.4 // indirect
-	golang.org/x/crypto v0.47.0 // indirect
-	golang.org/x/mod v0.32.0 // indirect
+	golang.org/x/crypto v0.48.0 // indirect
+	golang.org/x/mod v0.33.0 // indirect
 	golang.org/x/sync v0.19.0 // indirect
-	golang.org/x/sys v0.40.0 // indirect
-	golang.org/x/text v0.33.0 // indirect
-	golang.org/x/tools v0.41.0 // indirect
+	golang.org/x/sys v0.41.0 // indirect
+	golang.org/x/text v0.34.0 // indirect
+	golang.org/x/tools v0.42.0 // indirect
 )

go_backend/go.sum

@@ -2,16 +2,18 @@ github.com/Masterminds/semver/v3 v3.2.1 h1:RN9w6+7QoMeJVGyfmbcgs28Br8cvmnucEXnY0
 github.com/Masterminds/semver/v3 v3.2.1/go.mod h1:qvl/7zhW3nngYb5+80sSMF+FG2BjYrf8m9wsX0PNOMQ=
 github.com/andybalholm/brotli v1.0.6 h1:Yf9fFpf49Zrxb9NlQaluyE92/+X7UVHlhMNJN2sxfOI=
 github.com/andybalholm/brotli v1.0.6/go.mod h1:fO7iG3H7G2nSZ7m0zPUDn85XEX2GTukHGRSepvi9Eig=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dlclark/regexp2 v1.11.4 h1:rPYF9/LECdNymJufQKmri9gV604RvvABwgOA8un7yAo=
 github.com/dlclark/regexp2 v1.11.4/go.mod h1:DHkYz0B9wPfa6wondMfaivmHpzrQ3v9q8cnmRbL6yW8=
 github.com/dop251/goja v0.0.0-20260106131823-651366fbe6e3 h1:bVp3yUzvSAJzu9GqID+Z96P+eu5TKnIMJSV4QaZMauM=
 github.com/dop251/goja v0.0.0-20260106131823-651366fbe6e3/go.mod h1:MxLav0peU43GgvwVgNbLAj1s/bSGboKkhuULvq/7hx4=
-github.com/go-flac/flacpicture v0.3.0 h1:LkmTxzFLIynwfhHiZsX0s8xcr3/u33MzvV89u+zOT8I=
-github.com/go-flac/flacpicture v0.3.0/go.mod h1:DPbrzVYQ3fJcvSgLFp9HXIrEQEdfdk/+m0nQCzwodZI=
-github.com/go-flac/flacvorbis v0.2.0 h1:KH0xjpkNTXFER4cszH4zeJxYcrHbUobz/RticWGOESs=
-github.com/go-flac/flacvorbis v0.2.0/go.mod h1:uIysHOtuU7OLGoCRG92bvnkg7QEqHx19qKRV6K1pBrI=
-github.com/go-flac/go-flac v1.0.0 h1:6qI9XOVLcO50xpzm3nXvO31BgDgHhnr/p/rER/K/doY=
-github.com/go-flac/go-flac v1.0.0/go.mod h1:WnZhcpmq4u1UdZMNn9LYSoASpWOCMOoxXxcWEHSzkW8=
+github.com/go-flac/flacpicture/v2 v2.0.2 h1:HCaJIVZpxnpdWs6G3ECEVRelzqS5xOi1Ba1AGmtXbzE=
+github.com/go-flac/flacpicture/v2 v2.0.2/go.mod h1:DMZBPWPAmdLqNhqFSy5ZBs9wyBzOekXutGfP7/TFCuo=
+github.com/go-flac/flacvorbis/v2 v2.0.2 h1:xCL3OhxrxWkHrbWUBvGNe+6FQ03yLmBbz0v5z4V2PoQ=
+github.com/go-flac/flacvorbis/v2 v2.0.2/go.mod h1:SwTB5gs13VaM/N7rstwPoUsPibiMKklgwybYP9dYo2g=
+github.com/go-flac/go-flac/v2 v2.0.4 h1:atf/kFa8U9idtkA//NO22XGr+MzQLeXZecnmP9sYBf0=
+github.com/go-flac/go-flac/v2 v2.0.4/go.mod h1:sYOlTKxutMW0RDYF+KlD6Zn+VOCZlIFQG/r/usPveCs=
 github.com/go-sourcemap/sourcemap v2.1.3+incompatible h1:W1iEw64niKVGogNgBN3ePyLFfuisuzeidWPMPWmECqU=
 github.com/go-sourcemap/sourcemap v2.1.3+incompatible/go.mod h1:F8jJfvm2KbVjc5NqelyYJmf/v5J0dwNLS2mL4sNA1Jg=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
@@ -20,23 +22,43 @@ github.com/google/pprof v0.0.0-20230207041349-798e818bf904 h1:4/hN5RUoecvl+RmJRE
 github.com/google/pprof v0.0.0-20230207041349-798e818bf904/go.mod h1:uglQLonpP8qtYCYyzA+8c/9qtqgA3qsXGYqCPKARAFg=
 github.com/klauspost/compress v1.17.4 h1:Ej5ixsIri7BrIjBkRZLTo6ghwrEtHFk7ijlczPW4fZ4=
 github.com/klauspost/compress v1.17.4/go.mod h1:/dCuZOvVtNoHsyb+cuJD3itjs3NbnF6KH9zAO4BDxPM=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/refraction-networking/utls v1.8.2 h1:j4Q1gJj0xngdeH+Ox/qND11aEfhpgoEvV+S9iJ2IdQo=
 github.com/refraction-networking/utls v1.8.2/go.mod h1:jkSOEkLqn+S/jtpEHPOsVv/4V4EVnelwbMQl4vCWXAM=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 golang.org/x/crypto v0.47.0 h1:V6e3FRj+n4dbpw86FJ8Fv7XVOql7TEwpHapKoMJ/GO8=
 golang.org/x/crypto v0.47.0/go.mod h1:ff3Y9VzzKbwSSEzWqJsJVBnWmRwRSHt/6Op5n9bQc4A=
-golang.org/x/mobile v0.0.0-20260120165949-40bd9ace6ce4 h1:C3JuLOLhdaE75vk5m7u18NvZciRk+lnO34xcXl3NPTU=
-golang.org/x/mobile v0.0.0-20260120165949-40bd9ace6ce4/go.mod h1:yHJY0EGzMJ0i5ONrrhdpDSSnoyres5LO7D2hSIbJJ5I=
+golang.org/x/crypto v0.48.0 h1:/VRzVqiRSggnhY7gNRxPauEQ5Drw9haKdM0jqfcCFts=
+golang.org/x/crypto v0.48.0/go.mod h1:r0kV5h3qnFPlQnBSrULhlsRfryS2pmewsg+XfMgkVos=
+golang.org/x/mobile v0.0.0-20260204172633-1dceadbbeea3 h1:NiJtT7g4ncNFVjVZMAYNBrPSNhIjFYPj8UKA8MEw2A4=
+golang.org/x/mobile v0.0.0-20260204172633-1dceadbbeea3/go.mod h1:wReH3Q1agKmmLapipWFnd4NSs8KPz3fK6mSEZjXLkrg=
+golang.org/x/mobile v0.0.0-20260209203831-923679eb55af h1:VqXrZNyqFISxo0rNDFZQlRDRIp7RXSJDeh/LbrK+W1k=
+golang.org/x/mobile v0.0.0-20260209203831-923679eb55af/go.mod h1:tbwefIr7RlQD1OpZ0KEZ9nux/uiihAOGdafgZfJkmII=
 golang.org/x/mod v0.32.0 h1:9F4d3PHLljb6x//jOyokMv3eX+YDeepZSEo3mFJy93c=
 golang.org/x/mod v0.32.0/go.mod h1:SgipZ/3h2Ci89DlEtEXWUk/HteuRin+HHhN+WbNhguU=
+golang.org/x/mod v0.33.0 h1:tHFzIWbBifEmbwtGz65eaWyGiGZatSrT9prnU8DbVL8=
+golang.org/x/mod v0.33.0/go.mod h1:swjeQEj+6r7fODbD2cqrnje9PnziFuw4bmLbBZFrQ5w=
 golang.org/x/net v0.49.0 h1:eeHFmOGUTtaaPSGNmjBKpbng9MulQsJURQUAfUwY++o=
 golang.org/x/net v0.49.0/go.mod h1:/ysNB2EvaqvesRkuLAyjI1ycPZlQHM3q01F02UY/MV8=
+golang.org/x/net v0.50.0 h1:ucWh9eiCGyDR3vtzso0WMQinm2Dnt8cFMuQa9K33J60=
+golang.org/x/net v0.50.0/go.mod h1:UgoSli3F/pBgdJBHCTc+tp3gmrU4XswgGRgtnwWTfyM=
 golang.org/x/sync v0.19.0 h1:vV+1eWNmZ5geRlYjzm2adRgW2/mcpevXNg50YZtPCE4=
 golang.org/x/sync v0.19.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
 golang.org/x/sys v0.40.0 h1:DBZZqJ2Rkml6QMQsZywtnjnnGvHza6BTfYFWY9kjEWQ=
 golang.org/x/sys v0.40.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/sys v0.41.0 h1:Ivj+2Cp/ylzLiEU89QhWblYnOE9zerudt9Ftecq2C6k=
+golang.org/x/sys v0.41.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
 golang.org/x/text v0.33.0 h1:B3njUFyqtHDUI5jMn1YIr5B0IE2U0qck04r6d4KPAxE=
 golang.org/x/text v0.33.0/go.mod h1:LuMebE6+rBincTi9+xWTY8TztLzKHc/9C1uBCG27+q8=
+golang.org/x/text v0.34.0 h1:oL/Qq0Kdaqxa1KbNeMKwQq0reLCCaFtqu2eNuSeNHbk=
+golang.org/x/text v0.34.0/go.mod h1:homfLqTYRFyVYemLBFl5GgL/DWEiH5wcsQ5gSh1yziA=
 golang.org/x/tools v0.41.0 h1:a9b8iMweWG+S0OBnlU36rzLp20z1Rp10w+IY2czHTQc=
 golang.org/x/tools v0.41.0/go.mod h1:XSY6eDqxVNiYgezAVqqCeihT4j1U2CCsqvH3WhQpnlg=
+golang.org/x/tools v0.42.0 h1:uNgphsn75Tdz5Ji2q36v/nsFSfR/9BRFvqhGBaJGd5k=
+golang.org/x/tools v0.42.0/go.mod h1:Ma6lCIwGZvHK6XtgbswSoWroEkhugApmsXyrUmBhfr0=
 gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

go_backend/httputil.go

@@ -15,11 +15,7 @@ import (
 	"time"
 )
 
-// getRandomUserAgent generates a random Windows Chrome User-Agent string
-// Uses modern Chrome format with build and patch numbers
-// Windows 11 still reports as "Windows NT 10.0" for compatibility
 func getRandomUserAgent() string {
-	// Chrome version 120-145 (modern range)
 	chromeVersion := rand.Intn(26) + 120
 	chromeBuild := rand.Intn(1500) + 6000
 	chromePatch := rand.Intn(200) + 100
@@ -38,10 +34,9 @@ const (
 	SongLinkTimeout   = 30 * time.Second
 	DefaultMaxRetries = 3
 	DefaultRetryDelay = 1 * time.Second
-	Second            = time.Second // Exported for use in other files
+	Second            = time.Second
 )
 
-// Shared transport with connection pooling to prevent TCP exhaustion
 var sharedTransport = &http.Transport{
 	DialContext: (&net.Dialer{
 		Timeout:   30 * time.Second,
@@ -60,6 +55,27 @@ var sharedTransport = &http.Transport{
 	DisableCompression:    true,
 }
 
+// metadataTransport is a separate transport for metadata API calls (Deezer, Spotify, SongLink).
+// Isolated from download traffic so that download failures cannot poison
+// the connection pool used by metadata enrichment.
+var metadataTransport = &http.Transport{
+	DialContext: (&net.Dialer{
+		Timeout:   30 * time.Second,
+		KeepAlive: 30 * time.Second,
+	}).DialContext,
+	MaxIdleConns:          30,
+	MaxIdleConnsPerHost:   5,
+	MaxConnsPerHost:       10,
+	IdleConnTimeout:       90 * time.Second,
+	TLSHandshakeTimeout:   10 * time.Second,
+	ExpectContinueTimeout: 1 * time.Second,
+	DisableKeepAlives:     false,
+	ForceAttemptHTTP2:     true,
+	WriteBufferSize:       32 * 1024,
+	ReadBufferSize:        32 * 1024,
+	DisableCompression:    true,
+}
+
 var sharedClient = &http.Client{
 	Transport: sharedTransport,
 	Timeout:   DefaultTimeout,
@@ -77,6 +93,15 @@ func NewHTTPClientWithTimeout(timeout time.Duration) *http.Client {
 	}
 }
 
+// NewMetadataHTTPClient creates an HTTP client using the isolated metadata transport.
+// Use this for API calls that should not be affected by download traffic.
+func NewMetadataHTTPClient(timeout time.Duration) *http.Client {
+	return &http.Client{
+		Transport: metadataTransport,
+		Timeout:   timeout,
+	}
+}
+
 func GetSharedClient() *http.Client {
 	return sharedClient
 }
@@ -85,9 +110,9 @@ func GetDownloadClient() *http.Client {
 	return downloadClient
 }
 
-// CloseIdleConnections closes idle connections in the shared transport
 func CloseIdleConnections() {
 	sharedTransport.CloseIdleConnections()
+	metadataTransport.CloseIdleConnections()
 }
 
 // Also checks for ISP blocking on errors
@@ -117,16 +142,12 @@ func DefaultRetryConfig() RetryConfig {
 	}
 }
 
-// DoRequestWithRetry executes an HTTP request with retry logic and exponential backoff
-// Handles 429 (Too Many Requests) responses with Retry-After header
-// Also detects and logs ISP blocking
 func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConfig) (*http.Response, error) {
 	var lastErr error
 	delay := config.InitialDelay
 	requestURL := req.URL.String()
 
 	for attempt := 0; attempt <= config.MaxRetries; attempt++ {
-		// Clone request for retry (body needs to be re-readable)
 		reqCopy := req.Clone(req.Context())
 		reqCopy.Header.Set("User-Agent", getRandomUserAgent())
 
@@ -134,9 +155,7 @@ func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConf
 		if err != nil {
 			lastErr = err
 
-			// Check for ISP blocking on network errors
 			if CheckAndLogISPBlocking(err, requestURL, "HTTP") {
-				// Don't retry if ISP blocking is detected - it won't help
 				return nil, WrapErrorWithISPCheck(err, requestURL, "HTTP")
 			}
 
@@ -149,12 +168,10 @@ func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConf
 			continue
 		}
 
-		// Success
 		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
 			return resp, nil
 		}
 
-		// Handle rate limiting (429)
 		if resp.StatusCode == 429 {
 			resp.Body.Close()
 			retryAfter := getRetryAfterDuration(resp)
@@ -194,7 +211,6 @@ func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConf
 			}
 		}
 
-		// Server errors (5xx) - retry
 		if resp.StatusCode >= 500 {
 			resp.Body.Close()
 			lastErr = fmt.Errorf("server error: HTTP %d", resp.StatusCode)
@@ -206,7 +222,6 @@ func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConf
 			continue
 		}
 
-		// Client errors (4xx except 429) - don't retry
 		return resp, nil
 	}
 
@@ -225,12 +240,10 @@ func getRetryAfterDuration(resp *http.Response) time.Duration {
 		return 60 * time.Second // Default wait time
 	}
 
-	// Try parsing as seconds
 	if seconds, err := strconv.Atoi(retryAfter); err == nil {
 		return time.Duration(seconds) * time.Second
 	}
 
-	// Try parsing as HTTP date
 	if t, err := http.ParseTime(retryAfter); err == nil {
 		duration := time.Until(t)
 		if duration > 0 {
@@ -241,8 +254,6 @@ func getRetryAfterDuration(resp *http.Response) time.Duration {
 	return 60 * time.Second // Default
 }
 
-// ReadResponseBody reads and returns the response body
-// Returns error if body is empty
 func ReadResponseBody(resp *http.Response) ([]byte, error) {
 	if resp == nil {
 		return nil, fmt.Errorf("response is nil")
@@ -272,14 +283,12 @@ func ValidateResponse(resp *http.Response) error {
 	return nil
 }
 
-// BuildErrorMessage creates a detailed error message for API failures
 func BuildErrorMessage(apiURL string, statusCode int, responsePreview string) string {
 	msg := fmt.Sprintf("API %s failed", apiURL)
 	if statusCode > 0 {
 		msg += fmt.Sprintf(" (HTTP %d)", statusCode)
 	}
 	if responsePreview != "" {
-		// Truncate preview if too long
 		if len(responsePreview) > 100 {
 			responsePreview = responsePreview[:100] + "..."
 		}
@@ -298,18 +307,14 @@ func (e *ISPBlockingError) Error() string {
 	return fmt.Sprintf("ISP blocking detected for %s: %s", e.Domain, e.Reason)
 }
 
-// IsISPBlocking checks if an error is likely caused by ISP blocking
-// Returns the ISPBlockingError if detected, nil otherwise
 func IsISPBlocking(err error, requestURL string) *ISPBlockingError {
 	if err == nil {
 		return nil
 	}
 
-	// Extract domain from URL
 	domain := extractDomain(requestURL)
 	errStr := strings.ToLower(err.Error())
 
-	// Check for DNS resolution failure (common ISP blocking method)
 	var dnsErr *net.DNSError
 	if errors.As(err, &dnsErr) {
 		if dnsErr.IsNotFound || dnsErr.IsTemporary {
@@ -321,11 +326,9 @@ func IsISPBlocking(err error, requestURL string) *ISPBlockingError {
 		}
 	}
 
-	// Check for connection refused (ISP firewall blocking)
 	var opErr *net.OpError
 	if errors.As(err, &opErr) {
 		if opErr.Op == "dial" {
-			// Check for specific syscall errors
 			var syscallErr syscall.Errno
 			if errors.As(opErr.Err, &syscallErr) {
 				switch syscallErr {
@@ -364,7 +367,6 @@ func IsISPBlocking(err error, requestURL string) *ISPBlockingError {
 		}
 	}
 
-	// Check for TLS handshake failure (ISP MITM or blocking HTTPS)
 	var tlsErr *tls.RecordHeaderError
 	if errors.As(err, &tlsErr) {
 		return &ISPBlockingError{
@@ -425,7 +427,6 @@ func extractDomain(rawURL string) string {
 
 	parsed, err := url.Parse(rawURL)
 	if err != nil {
-		// Try to extract domain manually
 		rawURL = strings.TrimPrefix(rawURL, "https://")
 		rawURL = strings.TrimPrefix(rawURL, "http://")
 		if idx := strings.Index(rawURL, "/"); idx > 0 {

go_backend/httputil_utls.go

@@ -35,7 +35,6 @@ func newUTLSTransport() *utlsTransport {
 }
 
 func (t *utlsTransport) RoundTrip(req *http.Request) (*http.Response, error) {
-	// For non-HTTPS, use standard transport
 	if req.URL.Scheme != "https" {
 		return sharedTransport.RoundTrip(req)
 	}
@@ -44,29 +43,24 @@ func (t *utlsTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 	port := t.getPort(req.URL)
 	addr := net.JoinHostPort(host, port)
 
-	// Dial TCP connection
 	conn, err := t.dialer.DialContext(req.Context(), "tcp", addr)
 	if err != nil {
 		return nil, err
 	}
 
-	// Create uTLS connection with Chrome fingerprint (supports HTTP/2 ALPN)
 	tlsConn := utls.UClient(conn, &utls.Config{
 		ServerName: host,
-		NextProtos: []string{"h2", "http/1.1"}, // Prefer HTTP/2
+		NextProtos: []string{"h2", "http/1.1"},
 	}, utls.HelloChrome_Auto)
 
-	// Perform TLS handshake
 	if err := tlsConn.Handshake(); err != nil {
 		conn.Close()
 		return nil, err
 	}
 
-	// Check if server supports HTTP/2
 	negotiatedProto := tlsConn.ConnectionState().NegotiatedProtocol
 
 	if negotiatedProto == "h2" {
-		// Use HTTP/2 transport
 		h2Transport := &http2.Transport{
 			DialTLSContext: func(ctx context.Context, network, addr string, cfg *tls.Config) (net.Conn, error) {
 				return tlsConn, nil
@@ -77,7 +71,6 @@ func (t *utlsTransport) RoundTrip(req *http.Request) (*http.Response, error) {
 		return h2Transport.RoundTrip(req)
 	}
 
-	// Fallback to HTTP/1.1
 	transport := &http.Transport{
 		DialTLSContext: func(ctx context.Context, network, addr string) (net.Conn, error) {
 			return tlsConn, nil

go_backend/library_scan.go

@@ -0,0 +1,616 @@
+package gobackend
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+)
+
+// LibraryScanResult represents metadata from a scanned audio file
+type LibraryScanResult struct {
+	ID          string `json:"id"`
+	TrackName   string `json:"trackName"`
+	ArtistName  string `json:"artistName"`
+	AlbumName   string `json:"albumName"`
+	AlbumArtist string `json:"albumArtist,omitempty"`
+	FilePath    string `json:"filePath"`
+	CoverPath   string `json:"coverPath,omitempty"`
+	ScannedAt   string `json:"scannedAt"`
+	FileModTime int64  `json:"fileModTime,omitempty"` // Unix timestamp in milliseconds
+	ISRC        string `json:"isrc,omitempty"`
+	TrackNumber int    `json:"trackNumber,omitempty"`
+	DiscNumber  int    `json:"discNumber,omitempty"`
+	Duration    int    `json:"duration,omitempty"`
+	ReleaseDate string `json:"releaseDate,omitempty"`
+	BitDepth    int    `json:"bitDepth,omitempty"`
+	SampleRate  int    `json:"sampleRate,omitempty"`
+	Bitrate     int    `json:"bitrate,omitempty"` // kbps, for lossy formats (MP3, Opus, Vorbis)
+	Genre       string `json:"genre,omitempty"`
+	Format      string `json:"format,omitempty"`
+}
+
+type LibraryScanProgress struct {
+	TotalFiles   int     `json:"total_files"`
+	ScannedFiles int     `json:"scanned_files"`
+	CurrentFile  string  `json:"current_file"`
+	ErrorCount   int     `json:"error_count"`
+	ProgressPct  float64 `json:"progress_pct"`
+	IsComplete   bool    `json:"is_complete"`
+}
+
+// IncrementalScanResult contains results of an incremental library scan
+type IncrementalScanResult struct {
+	Scanned      []LibraryScanResult `json:"scanned"`      // New or updated files
+	DeletedPaths []string            `json:"deletedPaths"` // Files that no longer exist
+	SkippedCount int                 `json:"skippedCount"` // Files that were unchanged
+	TotalFiles   int                 `json:"totalFiles"`   // Total files in folder
+}
+
+var (
+	libraryScanProgress   LibraryScanProgress
+	libraryScanProgressMu sync.RWMutex
+	libraryScanCancel     chan struct{}
+	libraryScanCancelMu   sync.Mutex
+	libraryCoverCacheDir  string
+	libraryCoverCacheMu   sync.RWMutex
+)
+
+var supportedAudioFormats = map[string]bool{
+	".flac": true,
+	".m4a":  true,
+	".mp3":  true,
+	".opus": true,
+	".ogg":  true,
+}
+
+func SetLibraryCoverCacheDir(cacheDir string) {
+	libraryCoverCacheMu.Lock()
+	libraryCoverCacheDir = cacheDir
+	libraryCoverCacheMu.Unlock()
+}
+
+func ScanLibraryFolder(folderPath string) (string, error) {
+	if folderPath == "" {
+		return "[]", fmt.Errorf("folder path is empty")
+	}
+
+	info, err := os.Stat(folderPath)
+	if err != nil {
+		return "[]", fmt.Errorf("folder not found: %w", err)
+	}
+	if !info.IsDir() {
+		return "[]", fmt.Errorf("path is not a folder: %s", folderPath)
+	}
+
+	libraryScanProgressMu.Lock()
+	libraryScanProgress = LibraryScanProgress{}
+	libraryScanProgressMu.Unlock()
+
+	libraryScanCancelMu.Lock()
+	if libraryScanCancel != nil {
+		close(libraryScanCancel)
+	}
+	libraryScanCancel = make(chan struct{})
+	cancelCh := libraryScanCancel
+	libraryScanCancelMu.Unlock()
+
+	var audioFiles []string
+	err = filepath.Walk(folderPath, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return nil
+		}
+
+		select {
+		case <-cancelCh:
+			return fmt.Errorf("scan cancelled")
+		default:
+		}
+
+		if !info.IsDir() {
+			ext := strings.ToLower(filepath.Ext(path))
+			if supportedAudioFormats[ext] {
+				audioFiles = append(audioFiles, path)
+			}
+		}
+		return nil
+	})
+
+	if err != nil {
+		return "[]", err
+	}
+
+	totalFiles := len(audioFiles)
+	libraryScanProgressMu.Lock()
+	libraryScanProgress.TotalFiles = totalFiles
+	libraryScanProgressMu.Unlock()
+
+	if totalFiles == 0 {
+		libraryScanProgressMu.Lock()
+		libraryScanProgress.IsComplete = true
+		libraryScanProgressMu.Unlock()
+		return "[]", nil
+	}
+
+	GoLog("[LibraryScan] Found %d audio files to scan\n", totalFiles)
+
+	results := make([]LibraryScanResult, 0, totalFiles)
+	scanTime := time.Now().UTC().Format(time.RFC3339)
+	errorCount := 0
+
+	for i, filePath := range audioFiles {
+		select {
+		case <-cancelCh:
+			return "[]", fmt.Errorf("scan cancelled")
+		default:
+		}
+
+		libraryScanProgressMu.Lock()
+		libraryScanProgress.ScannedFiles = i + 1
+		libraryScanProgress.CurrentFile = filepath.Base(filePath)
+		libraryScanProgress.ProgressPct = float64(i+1) / float64(totalFiles) * 100
+		libraryScanProgressMu.Unlock()
+
+		result, err := scanAudioFile(filePath, scanTime)
+		if err != nil {
+			errorCount++
+			GoLog("[LibraryScan] Error scanning %s: %v\n", filePath, err)
+			continue
+		}
+
+		results = append(results, *result)
+	}
+
+	libraryScanProgressMu.Lock()
+	libraryScanProgress.ErrorCount = errorCount
+	libraryScanProgress.IsComplete = true
+	libraryScanProgressMu.Unlock()
+
+	GoLog("[LibraryScan] Scan complete: %d tracks found, %d errors\n", len(results), errorCount)
+
+	jsonBytes, err := json.Marshal(results)
+	if err != nil {
+		return "[]", fmt.Errorf("failed to marshal results: %w", err)
+	}
+
+	return string(jsonBytes), nil
+}
+
+func scanAudioFile(filePath, scanTime string) (*LibraryScanResult, error) {
+	ext := strings.ToLower(filepath.Ext(filePath))
+
+	result := &LibraryScanResult{
+		ID:        generateLibraryID(filePath),
+		FilePath:  filePath,
+		ScannedAt: scanTime,
+		Format:    strings.TrimPrefix(ext, "."),
+	}
+
+	// Get file modification time
+	if info, err := os.Stat(filePath); err == nil {
+		result.FileModTime = info.ModTime().UnixMilli()
+	}
+
+	libraryCoverCacheMu.RLock()
+	coverCacheDir := libraryCoverCacheDir
+	libraryCoverCacheMu.RUnlock()
+	if coverCacheDir != "" && ext != ".m4a" {
+		coverPath, err := SaveCoverToCache(filePath, coverCacheDir)
+		if err == nil && coverPath != "" {
+			result.CoverPath = coverPath
+		}
+	}
+
+	switch ext {
+	case ".flac":
+		return scanFLACFile(filePath, result)
+	case ".m4a":
+		return scanM4AFile(filePath, result)
+	case ".mp3":
+		return scanMP3File(filePath, result)
+	case ".opus", ".ogg":
+		return scanOggFile(filePath, result)
+	default:
+		return scanFromFilename(filePath, result)
+	}
+}
+
+func scanFLACFile(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
+	metadata, err := ReadMetadata(filePath)
+	if err != nil {
+		return scanFromFilename(filePath, result)
+	}
+
+	result.TrackName = metadata.Title
+	result.ArtistName = metadata.Artist
+	result.AlbumName = metadata.Album
+	result.AlbumArtist = metadata.AlbumArtist
+	result.ISRC = metadata.ISRC
+	result.TrackNumber = metadata.TrackNumber
+	result.DiscNumber = metadata.DiscNumber
+	result.ReleaseDate = metadata.Date
+	result.Genre = metadata.Genre
+
+	quality, err := GetAudioQuality(filePath)
+	if err == nil {
+		result.BitDepth = quality.BitDepth
+		result.SampleRate = quality.SampleRate
+		if quality.SampleRate > 0 && quality.TotalSamples > 0 {
+			result.Duration = int(quality.TotalSamples / int64(quality.SampleRate))
+		}
+	}
+
+	if result.TrackName == "" {
+		result.TrackName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
+	}
+	if result.ArtistName == "" {
+		result.ArtistName = "Unknown Artist"
+	}
+	if result.AlbumName == "" {
+		result.AlbumName = "Unknown Album"
+	}
+
+	return result, nil
+}
+
+func scanM4AFile(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
+	quality, err := GetM4AQuality(filePath)
+	if err == nil {
+		result.BitDepth = quality.BitDepth
+		result.SampleRate = quality.SampleRate
+	}
+
+	return scanFromFilename(filePath, result)
+}
+
+func scanMP3File(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
+	metadata, err := ReadID3Tags(filePath)
+	if err != nil {
+		GoLog("[LibraryScan] ID3 read error for %s: %v\n", filePath, err)
+		return scanFromFilename(filePath, result)
+	}
+
+	result.TrackName = metadata.Title
+	result.ArtistName = metadata.Artist
+	result.AlbumName = metadata.Album
+	result.AlbumArtist = metadata.AlbumArtist
+	result.TrackNumber = metadata.TrackNumber
+	result.DiscNumber = metadata.DiscNumber
+	result.Genre = metadata.Genre
+	if metadata.Date != "" {
+		result.ReleaseDate = metadata.Date
+	} else {
+		result.ReleaseDate = metadata.Year
+	}
+	result.ISRC = metadata.ISRC
+
+	quality, err := GetMP3Quality(filePath)
+	if err == nil {
+		result.SampleRate = quality.SampleRate
+		result.BitDepth = quality.BitDepth // 0 for lossy
+		result.Duration = quality.Duration
+		if quality.Bitrate > 0 {
+			result.Bitrate = quality.Bitrate / 1000 // convert bps to kbps
+		}
+	}
+
+	if result.TrackName == "" {
+		result.TrackName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
+	}
+	if result.ArtistName == "" {
+		result.ArtistName = "Unknown Artist"
+	}
+	if result.AlbumName == "" {
+		result.AlbumName = "Unknown Album"
+	}
+
+	return result, nil
+}
+
+func scanOggFile(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
+	metadata, err := ReadOggVorbisComments(filePath)
+	if err != nil {
+		GoLog("[LibraryScan] Ogg/Opus read error for %s: %v\n", filePath, err)
+		return scanFromFilename(filePath, result)
+	}
+
+	result.TrackName = metadata.Title
+	result.ArtistName = metadata.Artist
+	result.AlbumName = metadata.Album
+	result.AlbumArtist = metadata.AlbumArtist
+	result.ISRC = metadata.ISRC
+	result.TrackNumber = metadata.TrackNumber
+	result.DiscNumber = metadata.DiscNumber
+	result.Genre = metadata.Genre
+	result.ReleaseDate = metadata.Date
+
+	quality, err := GetOggQuality(filePath)
+	if err == nil {
+		result.SampleRate = quality.SampleRate
+		result.BitDepth = quality.BitDepth // 0 for lossy
+		result.Duration = quality.Duration
+		if quality.Bitrate > 0 {
+			result.Bitrate = quality.Bitrate / 1000 // convert bps to kbps
+		}
+	}
+
+	if result.TrackName == "" {
+		result.TrackName = strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
+	}
+	if result.ArtistName == "" {
+		result.ArtistName = "Unknown Artist"
+	}
+	if result.AlbumName == "" {
+		result.AlbumName = "Unknown Album"
+	}
+
+	return result, nil
+}
+
+func scanFromFilename(filePath string, result *LibraryScanResult) (*LibraryScanResult, error) {
+	filename := strings.TrimSuffix(filepath.Base(filePath), filepath.Ext(filePath))
+
+	parts := strings.SplitN(filename, " - ", 2)
+	if len(parts) == 2 {
+		if len(parts[0]) <= 3 && isNumeric(parts[0]) {
+			result.TrackName = parts[1]
+			result.ArtistName = "Unknown Artist"
+		} else {
+			result.ArtistName = parts[0]
+			result.TrackName = parts[1]
+		}
+	} else {
+		if len(filename) > 3 && isNumeric(filename[:2]) {
+			title := strings.TrimLeft(filename[2:], " .-")
+			result.TrackName = title
+		} else {
+			result.TrackName = filename
+		}
+		result.ArtistName = "Unknown Artist"
+	}
+
+	dir := filepath.Dir(filePath)
+	result.AlbumName = filepath.Base(dir)
+	if result.AlbumName == "." || result.AlbumName == "" {
+		result.AlbumName = "Unknown Album"
+	}
+
+	return result, nil
+}
+
+func isNumeric(s string) bool {
+	for _, c := range s {
+		if c < '0' || c > '9' {
+			return false
+		}
+	}
+	return len(s) > 0
+}
+
+func generateLibraryID(filePath string) string {
+	return fmt.Sprintf("lib_%x", hashString(filePath))
+}
+
+func hashString(s string) uint32 {
+	var hash uint32 = 5381
+	for _, c := range s {
+		hash = ((hash << 5) + hash) + uint32(c)
+	}
+	return hash
+}
+
+func GetLibraryScanProgress() string {
+	libraryScanProgressMu.RLock()
+	defer libraryScanProgressMu.RUnlock()
+
+	jsonBytes, _ := json.Marshal(libraryScanProgress)
+	return string(jsonBytes)
+}
+
+func CancelLibraryScan() {
+	libraryScanCancelMu.Lock()
+	defer libraryScanCancelMu.Unlock()
+
+	if libraryScanCancel != nil {
+		close(libraryScanCancel)
+		libraryScanCancel = nil
+	}
+}
+
+func ReadAudioMetadata(filePath string) (string, error) {
+	scanTime := time.Now().UTC().Format(time.RFC3339)
+	result, err := scanAudioFile(filePath, scanTime)
+	if err != nil {
+		return "", err
+	}
+
+	jsonBytes, err := json.Marshal(result)
+	if err != nil {
+		return "", fmt.Errorf("failed to marshal result: %w", err)
+	}
+
+	return string(jsonBytes), nil
+}
+
+// ScanLibraryFolderIncremental performs an incremental scan of the library folder
+// existingFilesJSON is a JSON object mapping filePath -> modTime (unix millis)
+// Only files that are new or have changed modification time will be scanned
+func ScanLibraryFolderIncremental(folderPath, existingFilesJSON string) (string, error) {
+	if folderPath == "" {
+		return "{}", fmt.Errorf("folder path is empty")
+	}
+
+	info, err := os.Stat(folderPath)
+	if err != nil {
+		return "{}", fmt.Errorf("folder not found: %w", err)
+	}
+	if !info.IsDir() {
+		return "{}", fmt.Errorf("path is not a folder: %s", folderPath)
+	}
+
+	// Parse existing files map
+	existingFiles := make(map[string]int64)
+	if existingFilesJSON != "" && existingFilesJSON != "{}" {
+		if err := json.Unmarshal([]byte(existingFilesJSON), &existingFiles); err != nil {
+			GoLog("[LibraryScan] Warning: failed to parse existing files JSON: %v\n", err)
+		}
+	}
+
+	GoLog("[LibraryScan] Incremental scan starting, %d existing files in database\n", len(existingFiles))
+
+	// Reset progress
+	libraryScanProgressMu.Lock()
+	libraryScanProgress = LibraryScanProgress{}
+	libraryScanProgressMu.Unlock()
+
+	// Setup cancellation
+	libraryScanCancelMu.Lock()
+	if libraryScanCancel != nil {
+		close(libraryScanCancel)
+	}
+	libraryScanCancel = make(chan struct{})
+	cancelCh := libraryScanCancel
+	libraryScanCancelMu.Unlock()
+
+	// Collect all audio files with their mod times
+	type fileInfo struct {
+		path    string
+		modTime int64
+	}
+	var currentFiles []fileInfo
+	currentPathSet := make(map[string]bool)
+
+	err = filepath.Walk(folderPath, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return nil
+		}
+
+		select {
+		case <-cancelCh:
+			return fmt.Errorf("scan cancelled")
+		default:
+		}
+
+		if !info.IsDir() {
+			ext := strings.ToLower(filepath.Ext(path))
+			if supportedAudioFormats[ext] {
+				currentFiles = append(currentFiles, fileInfo{
+					path:    path,
+					modTime: info.ModTime().UnixMilli(),
+				})
+				currentPathSet[path] = true
+			}
+		}
+		return nil
+	})
+
+	if err != nil {
+		return "{}", err
+	}
+
+	totalFiles := len(currentFiles)
+	libraryScanProgressMu.Lock()
+	libraryScanProgress.TotalFiles = totalFiles
+	libraryScanProgressMu.Unlock()
+
+	// Find files to scan (new or modified)
+	var filesToScan []fileInfo
+	skippedCount := 0
+
+	for _, f := range currentFiles {
+		existingModTime, exists := existingFiles[f.path]
+		if !exists {
+			// New file
+			filesToScan = append(filesToScan, f)
+		} else if f.modTime != existingModTime {
+			// Modified file
+			filesToScan = append(filesToScan, f)
+		} else {
+			// Unchanged file - skip
+			skippedCount++
+		}
+	}
+
+	// Find deleted files
+	var deletedPaths []string
+	for existingPath := range existingFiles {
+		if !currentPathSet[existingPath] {
+			deletedPaths = append(deletedPaths, existingPath)
+		}
+	}
+
+	GoLog("[LibraryScan] Incremental: %d to scan, %d skipped, %d deleted\n",
+		len(filesToScan), skippedCount, len(deletedPaths))
+
+	if len(filesToScan) == 0 {
+		libraryScanProgressMu.Lock()
+		libraryScanProgress.ScannedFiles = totalFiles
+		libraryScanProgress.IsComplete = true
+		libraryScanProgress.ProgressPct = 100
+		libraryScanProgressMu.Unlock()
+
+		result := IncrementalScanResult{
+			Scanned:      []LibraryScanResult{},
+			DeletedPaths: deletedPaths,
+			SkippedCount: skippedCount,
+			TotalFiles:   totalFiles,
+		}
+		jsonBytes, _ := json.Marshal(result)
+		return string(jsonBytes), nil
+	}
+
+	// Scan the files that need scanning
+	results := make([]LibraryScanResult, 0, len(filesToScan))
+	scanTime := time.Now().UTC().Format(time.RFC3339)
+	errorCount := 0
+
+	for i, f := range filesToScan {
+		select {
+		case <-cancelCh:
+			return "{}", fmt.Errorf("scan cancelled")
+		default:
+		}
+
+		libraryScanProgressMu.Lock()
+		libraryScanProgress.ScannedFiles = skippedCount + i + 1
+		libraryScanProgress.CurrentFile = filepath.Base(f.path)
+		libraryScanProgress.ProgressPct = float64(skippedCount+i+1) / float64(totalFiles) * 100
+		libraryScanProgressMu.Unlock()
+
+		result, err := scanAudioFile(f.path, scanTime)
+		if err != nil {
+			errorCount++
+			GoLog("[LibraryScan] Error scanning %s: %v\n", f.path, err)
+			continue
+		}
+
+		results = append(results, *result)
+	}
+
+	libraryScanProgressMu.Lock()
+	libraryScanProgress.ErrorCount = errorCount
+	libraryScanProgress.IsComplete = true
+	libraryScanProgress.ScannedFiles = totalFiles
+	libraryScanProgress.ProgressPct = 100
+	libraryScanProgressMu.Unlock()
+
+	GoLog("[LibraryScan] Incremental scan complete: %d scanned, %d skipped, %d deleted, %d errors\n",
+		len(results), skippedCount, len(deletedPaths), errorCount)
+
+	scanResult := IncrementalScanResult{
+		Scanned:      results,
+		DeletedPaths: deletedPaths,
+		SkippedCount: skippedCount,
+		TotalFiles:   totalFiles,
+	}
+
+	jsonBytes, err := json.Marshal(scanResult)
+	if err != nil {
+		return "{}", fmt.Errorf("failed to marshal results: %w", err)
+	}
+
+	return string(jsonBytes), nil
+}

go_backend/logbuffer.go

@@ -3,6 +3,7 @@ package gobackend
 import (
 	"encoding/json"
 	"fmt"
+	"regexp"
 	"strings"
 	"sync"
 	"time"
@@ -22,30 +23,55 @@ type LogBuffer struct {
 	loggingEnabled bool
 }
 
+const (
+	defaultLogBufferSize = 500
+	maxLogMessageLength  = 500
+)
+
 var (
 	globalLogBuffer *LogBuffer
 	logBufferOnce   sync.Once
+
+	authorizationBearerPattern = regexp.MustCompile(`(?i)\bAuthorization\b\s*[:=]\s*Bearer\s+[A-Za-z0-9._~+/\-]+=*`)
+	genericKeyValuePattern     = regexp.MustCompile(`(?i)\b(access[_\s-]?token|refresh[_\s-]?token|id[_\s-]?token|client[_\s-]?secret|authorization|password|api[_\s-]?key)\b(\s*[:=]\s*)([^\s,;]+)`)
+	queryTokenPattern          = regexp.MustCompile(`(?i)([?&](?:access_token|refresh_token|id_token|token|client_secret|api_key|apikey|password)=)[^&\s]+`)
+	bearerTokenPattern         = regexp.MustCompile(`(?i)\bBearer\s+[A-Za-z0-9._~+/\-]+=*`)
 )
 
-// GetLogBuffer returns the singleton log buffer instance
+func sanitizeSensitiveLogText(message string) string {
+	redacted := message
+	redacted = authorizationBearerPattern.ReplaceAllString(redacted, "Authorization: Bearer [REDACTED]")
+	redacted = genericKeyValuePattern.ReplaceAllString(redacted, `${1}${2}[REDACTED]`)
+	redacted = queryTokenPattern.ReplaceAllString(redacted, `${1}[REDACTED]`)
+	redacted = bearerTokenPattern.ReplaceAllString(redacted, "Bearer [REDACTED]")
+	return redacted
+}
+
 func GetLogBuffer() *LogBuffer {
 	logBufferOnce.Do(func() {
 		globalLogBuffer = &LogBuffer{
-			entries:        make([]LogEntry, 0, 1000),
-			maxSize:        1000,
+			entries:        make([]LogEntry, 0, defaultLogBufferSize),
+			maxSize:        defaultLogBufferSize,
 			loggingEnabled: false, // Default: disabled for performance (user can enable in settings)
 		}
 	})
 	return globalLogBuffer
 }
 
+func truncateLogMessage(message string) string {
+	runes := []rune(message)
+	if len(runes) <= maxLogMessageLength {
+		return message
+	}
+	return string(runes[:maxLogMessageLength]) + "...[truncated]"
+}
+
 func (lb *LogBuffer) SetLoggingEnabled(enabled bool) {
 	lb.mu.Lock()
 	defer lb.mu.Unlock()
 	lb.loggingEnabled = enabled
 }
 
-// IsLoggingEnabled returns whether logging is enabled
 func (lb *LogBuffer) IsLoggingEnabled() bool {
 	lb.mu.RLock()
 	defer lb.mu.RUnlock()
@@ -60,6 +86,9 @@ func (lb *LogBuffer) Add(level, tag, message string) {
 		return
 	}
 
+	message = sanitizeSensitiveLogText(message)
+	message = truncateLogMessage(message)
+
 	entry := LogEntry{
 		Timestamp: time.Now().Format("15:04:05.000"),
 		Level:     level,
@@ -75,7 +104,6 @@ func (lb *LogBuffer) Add(level, tag, message string) {
 	fmt.Printf("[%s] %s\n", tag, message)
 }
 
-// GetAll returns all log entries as JSON
 func (lb *LogBuffer) GetAll() string {
 	lb.mu.RLock()
 	defer lb.mu.RUnlock()
@@ -99,21 +127,18 @@ func (lb *LogBuffer) getSince(index int) ([]LogEntry, int) {
 	return entries, len(lb.entries)
 }
 
-// Clear clears all log entries
 func (lb *LogBuffer) Clear() {
 	lb.mu.Lock()
 	defer lb.mu.Unlock()
 	lb.entries = lb.entries[:0]
 }
 
-// Count returns the number of log entries
 func (lb *LogBuffer) Count() int {
 	lb.mu.RLock()
 	defer lb.mu.RUnlock()
 	return len(lb.entries)
 }
 
-// Helper functions for logging with different levels
 func LogDebug(tag, format string, args ...interface{}) {
 	GetLogBuffer().Add("DEBUG", tag, fmt.Sprintf(format, args...))
 }
@@ -163,15 +188,10 @@ func GoLog(format string, args ...interface{}) {
 	GetLogBuffer().Add(level, tag, message)
 }
 
-// Exported functions for Flutter
-
-// GetLogs returns all logs as JSON array
 func GetLogs() string {
 	return GetLogBuffer().GetAll()
 }
 
-// GetLogsSince returns logs since the given index
-// Returns JSON: {"logs": [...], "next_index": N}
 func GetLogsSince(index int) string {
 	entries, nextIndex := GetLogBuffer().getSince(index)
 	logsJson, _ := json.Marshal(entries)
@@ -179,17 +199,14 @@ func GetLogsSince(index int) string {
 	return result
 }
 
-// ClearLogs clears all logs
 func ClearLogs() {
 	GetLogBuffer().Clear()
 }
 
-// GetLogCount returns the number of log entries
 func GetLogCount() int {
 	return GetLogBuffer().Count()
 }
 
-// SetLoggingEnabled enables or disables logging from Flutter
 func SetLoggingEnabled(enabled bool) {
 	GetLogBuffer().SetLoggingEnabled(enabled)
 }

go_backend/lyrics.go

@@ -238,12 +238,9 @@ func (c *LyricsClient) durationMatches(lrcDuration, targetDuration float64) bool
 	return diff <= durationToleranceSec
 }
 
-// durationSec: track duration in seconds for matching, use 0 to skip duration matching
 func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName string, durationSec float64) (*LyricsResponse, error) {
-	// Normalize artist name - take first artist before comma/semicolon for better matching
 	primaryArtist := normalizeArtistName(artistName)
 
-	// Check cache first (use original artist name for cache key)
 	if cached, found := globalLyricsCache.Get(artistName, trackName, durationSec); found {
 		fmt.Printf("[Lyrics] Cache hit for: %s - %s\n", artistName, trackName)
 		cachedCopy := *cached
@@ -254,12 +251,10 @@ func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName st
 	var lyrics *LyricsResponse
 	var err error
 
-	// Helper to check if lyrics result is valid (has lines OR is instrumental)
 	isValidResult := func(l *LyricsResponse) bool {
 		return l != nil && (len(l.Lines) > 0 || l.Instrumental)
 	}
 
-	// Try exact match first with primary artist
 	lyrics, err = c.FetchLyricsWithMetadata(primaryArtist, trackName)
 	if err == nil && isValidResult(lyrics) {
 		lyrics.Source = "LRCLIB"
@@ -267,7 +262,6 @@ func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName st
 		return lyrics, nil
 	}
 
-	// Try with full artist name if different from primary
 	if primaryArtist != artistName {
 		lyrics, err = c.FetchLyricsWithMetadata(artistName, trackName)
 		if err == nil && isValidResult(lyrics) {
@@ -277,7 +271,6 @@ func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName st
 		}
 	}
 
-	// Try with simplified track name
 	simplifiedTrack := simplifyTrackName(trackName)
 	if simplifiedTrack != trackName {
 		lyrics, err = c.FetchLyricsWithMetadata(primaryArtist, simplifiedTrack)
@@ -288,7 +281,6 @@ func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName st
 		}
 	}
 
-	// Search with duration matching (use primary artist for search)
 	query := primaryArtist + " " + trackName
 	lyrics, err = c.FetchLyricsFromLRCLibSearch(query, durationSec)
 	if err == nil && isValidResult(lyrics) {
@@ -297,7 +289,6 @@ func (c *LyricsClient) FetchLyricsAllSources(spotifyID, trackName, artistName st
 		return lyrics, nil
 	}
 
-	// Search with simplified name and duration matching
 	if simplifiedTrack != trackName {
 		query = primaryArtist + " " + simplifiedTrack
 		lyrics, err = c.FetchLyricsFromLRCLibSearch(query, durationSec)
@@ -393,32 +384,6 @@ func msToLRCTimestamp(ms int64) string {
 	return fmt.Sprintf("[%02d:%02d.%02d]", minutes, seconds, centiseconds)
 }
 
-// Use convertToLRCWithMetadata for full LRC with headers
-// Kept for potential future use
-// func convertToLRC(lyrics *LyricsResponse) string {
-// 	if lyrics == nil || len(lyrics.Lines) == 0 {
-// 		return ""
-// 	}
-//
-// 	var builder strings.Builder
-//
-// 	if lyrics.SyncType == "LINE_SYNCED" {
-// 		for _, line := range lyrics.Lines {
-// 			timestamp := msToLRCTimestamp(line.StartTimeMs)
-// 			builder.WriteString(timestamp)
-// 			builder.WriteString(line.Words)
-// 			builder.WriteString("\n")
-// 		}
-// 	} else {
-// 		for _, line := range lyrics.Lines {
-// 			builder.WriteString(line.Words)
-// 			builder.WriteString("\n")
-// 		}
-// 	}
-//
-// 	return builder.String()
-// }
-
 func convertToLRCWithMetadata(lyrics *LyricsResponse, trackName, artistName string) string {
 	if lyrics == nil || len(lyrics.Lines) == 0 {
 		return ""
@@ -480,11 +445,7 @@ func simplifyTrackName(name string) string {
 	return strings.TrimSpace(result)
 }
 
-// normalizeArtistName extracts the primary artist from multi-artist strings
-// e.g., "HOYO-MiX, AURORA" -> "HOYO-MiX"
-// e.g., "Artist1; Artist2" -> "Artist1"
 func normalizeArtistName(name string) string {
-	// Split by common separators: ", " or "; " or " & " or " feat. " or " ft. "
 	separators := []string{", ", "; ", " & ", " feat. ", " ft. ", " featuring ", " with "}
 
 	result := name

go_backend/metadata.go

@@ -4,16 +4,97 @@ import (
 	"bytes"
 	"encoding/binary"
 	"fmt"
+	stdimage "image"
+	_ "image/gif"
+	_ "image/jpeg"
+	_ "image/png"
 	"io"
 	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
 
-	"github.com/go-flac/flacpicture"
-	"github.com/go-flac/flacvorbis"
-	"github.com/go-flac/go-flac"
+	"github.com/go-flac/flacpicture/v2"
+	"github.com/go-flac/flacvorbis/v2"
+	"github.com/go-flac/go-flac/v2"
 )
 
+func detectCoverMIME(coverPath string, coverData []byte) string {
+	// Prefer magic-byte detection over file extension.
+	// Some providers return non-JPEG data behind .jpg URLs.
+	if len(coverData) >= 8 &&
+		coverData[0] == 0x89 &&
+		coverData[1] == 0x50 &&
+		coverData[2] == 0x4E &&
+		coverData[3] == 0x47 &&
+		coverData[4] == 0x0D &&
+		coverData[5] == 0x0A &&
+		coverData[6] == 0x1A &&
+		coverData[7] == 0x0A {
+		return "image/png"
+	}
+	if len(coverData) >= 3 &&
+		coverData[0] == 0xFF &&
+		coverData[1] == 0xD8 &&
+		coverData[2] == 0xFF {
+		return "image/jpeg"
+	}
+	if len(coverData) >= 6 {
+		header := string(coverData[:6])
+		if header == "GIF87a" || header == "GIF89a" {
+			return "image/gif"
+		}
+	}
+	if len(coverData) >= 12 &&
+		string(coverData[:4]) == "RIFF" &&
+		string(coverData[8:12]) == "WEBP" {
+		return "image/webp"
+	}
+
+	switch strings.ToLower(filepath.Ext(strings.TrimSpace(coverPath))) {
+	case ".png":
+		return "image/png"
+	case ".jpg", ".jpeg":
+		return "image/jpeg"
+	case ".webp":
+		return "image/webp"
+	case ".gif":
+		return "image/gif"
+	}
+
+	return "image/jpeg"
+}
+
+func buildPictureBlock(coverPath string, coverData []byte) (flac.MetaDataBlock, error) {
+	if len(coverData) == 0 {
+		return flac.MetaDataBlock{}, fmt.Errorf("empty cover data")
+	}
+
+	mime := detectCoverMIME(coverPath, coverData)
+	picture := &flacpicture.MetadataBlockPicture{
+		PictureType: flacpicture.PictureTypeFrontCover,
+		MIME:        mime,
+		Description: "Front Cover",
+		ImageData:   coverData,
+	}
+
+	// Width/height/depth are optional in practice; keep zero when decode fails.
+	if cfg, format, err := stdimage.DecodeConfig(bytes.NewReader(coverData)); err == nil {
+		picture.Width = uint32(cfg.Width)
+		picture.Height = uint32(cfg.Height)
+		switch format {
+		case "png":
+			picture.ColorDepth = 32
+		case "jpeg":
+			picture.ColorDepth = 24
+		default:
+			picture.ColorDepth = 0
+		}
+	}
+
+	return picture.Marshal(), nil
+}
+
 type Metadata struct {
 	Title       string
 	Artist      string
@@ -29,6 +110,8 @@ type Metadata struct {
 	Genre       string
 	Label       string
 	Copyright   string
+	Composer    string
+	Comment     string
 }
 
 func EmbedMetadata(filePath string, metadata Metadata, coverPath string) error {
@@ -98,6 +181,14 @@ func EmbedMetadata(filePath string, metadata Metadata, coverPath string) error {
 		setComment(cmt, "COPYRIGHT", metadata.Copyright)
 	}
 
+	if metadata.Composer != "" {
+		setComment(cmt, "COMPOSER", metadata.Composer)
+	}
+
+	if metadata.Comment != "" {
+		setComment(cmt, "COMMENT", metadata.Comment)
+	}
+
 	cmtBlock := cmt.Marshal()
 	if cmtIdx >= 0 {
 		f.Meta[cmtIdx] = &cmtBlock
@@ -117,19 +208,12 @@ func EmbedMetadata(filePath string, metadata Metadata, coverPath string) error {
 					}
 				}
 
-				picture, err := flacpicture.NewFromImageData(
-					flacpicture.PictureTypeFrontCover,
-					"Front Cover",
-					coverData,
-					"image/jpeg",
-				)
+				picBlock, err := buildPictureBlock(coverPath, coverData)
 				if err != nil {
-					fmt.Printf("[Metadata] Warning: Failed to create picture block: %v\n", err)
-				} else {
-					picBlock := picture.Marshal()
-					f.Meta = append(f.Meta, &picBlock)
-					fmt.Printf("[Metadata] Cover art embedded successfully (%d bytes)\n", len(coverData))
+					return fmt.Errorf("failed to create picture block: %w", err)
 				}
+				f.Meta = append(f.Meta, &picBlock)
+				fmt.Printf("[Metadata] Cover art embedded successfully (%d bytes)\n", len(coverData))
 			}
 		} else {
 			fmt.Printf("[Metadata] Warning: Cover file does not exist: %s\n", coverPath)
@@ -206,6 +290,14 @@ func EmbedMetadataWithCoverData(filePath string, metadata Metadata, coverData []
 		setComment(cmt, "COPYRIGHT", metadata.Copyright)
 	}
 
+	if metadata.Composer != "" {
+		setComment(cmt, "COMPOSER", metadata.Composer)
+	}
+
+	if metadata.Comment != "" {
+		setComment(cmt, "COMMENT", metadata.Comment)
+	}
+
 	cmtBlock := cmt.Marshal()
 	if cmtIdx >= 0 {
 		f.Meta[cmtIdx] = &cmtBlock
@@ -220,25 +312,17 @@ func EmbedMetadataWithCoverData(filePath string, metadata Metadata, coverData []
 			}
 		}
 
-		picture, err := flacpicture.NewFromImageData(
-			flacpicture.PictureTypeFrontCover,
-			"Front Cover",
-			coverData,
-			"image/jpeg",
-		)
+		picBlock, err := buildPictureBlock("", coverData)
 		if err != nil {
-			fmt.Printf("[Metadata] Warning: Failed to create picture block: %v\n", err)
-		} else {
-			picBlock := picture.Marshal()
-			f.Meta = append(f.Meta, &picBlock)
-			fmt.Printf("[Metadata] Cover art embedded successfully (%d bytes)\n", len(coverData))
+			return fmt.Errorf("failed to create picture block: %w", err)
 		}
+		f.Meta = append(f.Meta, &picBlock)
+		fmt.Printf("[Metadata] Cover art embedded successfully (%d bytes)\n", len(coverData))
 	}
 
 	return f.Save(filePath)
 }
 
-// ReadMetadata reads metadata from a FLAC file
 func ReadMetadata(filePath string) (*Metadata, error) {
 	f, err := flac.ParseFile(filePath)
 	if err != nil {
@@ -293,6 +377,12 @@ func ReadMetadata(filePath string) (*Metadata, error) {
 				metadata.Date = getComment(cmt, "YEAR")
 			}
 
+			metadata.Genre = getComment(cmt, "GENRE")
+			metadata.Label = getComment(cmt, "ORGANIZATION")
+			metadata.Copyright = getComment(cmt, "COPYRIGHT")
+			metadata.Composer = getComment(cmt, "COMPOSER")
+			metadata.Comment = getComment(cmt, "COMMENT")
+
 			break
 		}
 	}
@@ -336,6 +426,39 @@ func fileExists(path string) bool {
 	return err == nil
 }
 
+func ExtractCoverArt(filePath string) ([]byte, error) {
+	f, err := flac.ParseFile(filePath)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse FLAC file: %w", err)
+	}
+
+	for _, meta := range f.Meta {
+		if meta.Type == flac.Picture {
+			pic, err := flacpicture.ParseFromMetaDataBlock(*meta)
+			if err != nil {
+				continue
+			}
+			if pic.PictureType == flacpicture.PictureTypeFrontCover && len(pic.ImageData) > 0 {
+				return pic.ImageData, nil
+			}
+		}
+	}
+
+	for _, meta := range f.Meta {
+		if meta.Type == flac.Picture {
+			pic, err := flacpicture.ParseFromMetaDataBlock(*meta)
+			if err != nil {
+				continue
+			}
+			if len(pic.ImageData) > 0 {
+				return pic.ImageData, nil
+			}
+		}
+	}
+
+	return nil, fmt.Errorf("no cover art found in file")
+}
+
 func EmbedLyrics(filePath string, lyrics string) error {
 	f, err := flac.ParseFile(filePath)
 	if err != nil {
@@ -418,35 +541,92 @@ func EmbedGenreLabel(filePath string, genre, label string) error {
 	return f.Save(filePath)
 }
 
-// ExtractLyrics extracts embedded lyrics from a FLAC file
 func ExtractLyrics(filePath string) (string, error) {
+	lower := strings.ToLower(filePath)
+
+	if strings.HasSuffix(lower, ".flac") {
+		return extractLyricsFromFlac(filePath)
+	}
+
+	if strings.HasSuffix(lower, ".mp3") {
+		meta, err := ReadID3Tags(filePath)
+		if err != nil || meta == nil {
+			return "", fmt.Errorf("no lyrics found in file")
+		}
+		if strings.TrimSpace(meta.Lyrics) != "" {
+			return meta.Lyrics, nil
+		}
+		if looksLikeEmbeddedLyrics(meta.Comment) {
+			return meta.Comment, nil
+		}
+		return "", fmt.Errorf("no lyrics found in file")
+	}
+
+	if strings.HasSuffix(lower, ".opus") || strings.HasSuffix(lower, ".ogg") {
+		meta, err := ReadOggVorbisComments(filePath)
+		if err != nil || meta == nil {
+			return "", fmt.Errorf("no lyrics found in file")
+		}
+		if strings.TrimSpace(meta.Lyrics) != "" {
+			return meta.Lyrics, nil
+		}
+		if looksLikeEmbeddedLyrics(meta.Comment) {
+			return meta.Comment, nil
+		}
+		return "", fmt.Errorf("no lyrics found in file")
+	}
+
+	return "", fmt.Errorf("unsupported file format for lyrics extraction")
+}
+
+func extractLyricsFromFlac(filePath string) (string, error) {
 	f, err := flac.ParseFile(filePath)
 	if err != nil {
 		return "", fmt.Errorf("failed to parse FLAC file: %w", err)
 	}
 
 	for _, meta := range f.Meta {
-		if meta.Type == flac.VorbisComment {
-			cmt, err := flacvorbis.ParseFromMetaDataBlock(*meta)
-			if err != nil {
-				continue
-			}
+		if meta.Type != flac.VorbisComment {
+			continue
+		}
 
-			lyrics, err := cmt.Get("LYRICS")
-			if err == nil && len(lyrics) > 0 && lyrics[0] != "" {
-				return lyrics[0], nil
-			}
+		cmt, err := flacvorbis.ParseFromMetaDataBlock(*meta)
+		if err != nil {
+			continue
+		}
 
-			lyrics, err = cmt.Get("UNSYNCEDLYRICS")
-			if err == nil && len(lyrics) > 0 && lyrics[0] != "" {
-				return lyrics[0], nil
-			}
+		lyrics, err := cmt.Get("LYRICS")
+		if err == nil && len(lyrics) > 0 && strings.TrimSpace(lyrics[0]) != "" {
+			return lyrics[0], nil
+		}
+
+		lyrics, err = cmt.Get("UNSYNCEDLYRICS")
+		if err == nil && len(lyrics) > 0 && strings.TrimSpace(lyrics[0]) != "" {
+			return lyrics[0], nil
 		}
 	}
 
 	return "", fmt.Errorf("no lyrics found in file")
 }
 
+func looksLikeEmbeddedLyrics(value string) bool {
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
+		return false
+	}
+
+	lower := strings.ToLower(trimmed)
+	if strings.Contains(lower, "[ar:") || strings.Contains(lower, "[ti:") {
+		return true
+	}
+
+	if strings.Contains(trimmed, "\n") && strings.Contains(trimmed, "[") && strings.Contains(trimmed, "]") {
+		return true
+	}
+
+	return false
+}
+
 type AudioQuality struct {
 	BitDepth     int   `json:"bit_depth"`
 	SampleRate   int   `json:"sample_rate"`
@@ -512,356 +692,6 @@ func GetAudioQuality(filePath string) (AudioQuality, error) {
 	return AudioQuality{}, fmt.Errorf("unsupported file format (not FLAC or M4A)")
 }
 
-// ========================================
-// M4A (MP4/AAC) Metadata Embedding
-// ========================================
-
-// EmbedM4AMetadata embeds metadata into an M4A file using iTunes-style atoms
-func EmbedM4AMetadata(filePath string, metadata Metadata, coverData []byte) error {
-	input, err := os.Open(filePath)
-	if err != nil {
-		return fmt.Errorf("failed to open M4A file: %w", err)
-	}
-	defer input.Close()
-
-	info, err := input.Stat()
-	if err != nil {
-		return fmt.Errorf("failed to stat M4A file: %w", err)
-	}
-	fileSize := info.Size()
-
-	moovHeader, moovFound, err := findAtomInRange(input, 0, fileSize, "moov", fileSize)
-	if err != nil {
-		return fmt.Errorf("failed to find moov atom: %w", err)
-	}
-	if !moovFound {
-		return fmt.Errorf("moov atom not found in M4A file")
-	}
-
-	moovContentStart := moovHeader.offset + moovHeader.headerSize
-	moovContentSize := moovHeader.size - moovHeader.headerSize
-
-	udtaHeader, udtaFound, err := findAtomInRange(input, moovContentStart, moovContentSize, "udta", fileSize)
-	if err != nil {
-		return fmt.Errorf("failed to locate udta atom: %w", err)
-	}
-
-	var metaHeader atomHeader
-	metaFound := false
-	if udtaFound {
-		udtaContentStart := udtaHeader.offset + udtaHeader.headerSize
-		udtaContentSize := udtaHeader.size - udtaHeader.headerSize
-		metaHeader, metaFound, err = findAtomInRange(input, udtaContentStart, udtaContentSize, "meta", fileSize)
-		if err != nil {
-			return fmt.Errorf("failed to locate meta atom: %w", err)
-		}
-	}
-
-	metaAtom := buildMetaAtom(metadata, coverData)
-	metaSize := int64(len(metaAtom))
-
-	var delta int64
-	var newUdtaSize int64
-	switch {
-	case udtaFound && metaFound:
-		delta = metaSize - metaHeader.size
-		newUdtaSize = udtaHeader.size + delta
-	case udtaFound && !metaFound:
-		delta = metaSize
-		newUdtaSize = udtaHeader.size + delta
-	case !udtaFound:
-		newUdtaSize = int64(8 + len(metaAtom))
-		delta = newUdtaSize
-	}
-
-	newMoovSize := moovHeader.size + delta
-	if moovHeader.headerSize == 8 && newMoovSize > int64(^uint32(0)) {
-		return fmt.Errorf("moov atom exceeds 32-bit size after update")
-	}
-	if udtaFound && udtaHeader.headerSize == 8 && newUdtaSize > int64(^uint32(0)) {
-		return fmt.Errorf("udta atom exceeds 32-bit size after update")
-	}
-	if !udtaFound && newUdtaSize > int64(^uint32(0)) {
-		return fmt.Errorf("udta atom exceeds 32-bit size after update")
-	}
-
-	tempPath := filePath + ".tmp"
-	output, err := os.OpenFile(tempPath, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, 0644)
-	if err != nil {
-		return fmt.Errorf("failed to create temp file: %w", err)
-	}
-	cleanupTemp := true
-	defer func() {
-		_ = output.Close()
-		if cleanupTemp {
-			_ = os.Remove(tempPath)
-		}
-	}()
-
-	switch {
-	case udtaFound && metaFound:
-		if err := copyRange(output, input, 0, moovHeader.offset); err != nil {
-			return err
-		}
-		if err := writeAtomHeader(output, "moov", newMoovSize, moovHeader.headerSize); err != nil {
-			return err
-		}
-		if err := copyRange(output, input, moovHeader.offset+moovHeader.headerSize, udtaHeader.offset-(moovHeader.offset+moovHeader.headerSize)); err != nil {
-			return err
-		}
-		if err := writeAtomHeader(output, "udta", newUdtaSize, udtaHeader.headerSize); err != nil {
-			return err
-		}
-		if err := copyRange(output, input, udtaHeader.offset+udtaHeader.headerSize, metaHeader.offset-(udtaHeader.offset+udtaHeader.headerSize)); err != nil {
-			return err
-		}
-		if _, err := output.Write(metaAtom); err != nil {
-			return fmt.Errorf("failed to write meta atom: %w", err)
-		}
-		metaEnd := metaHeader.offset + metaHeader.size
-		if err := copyRange(output, input, metaEnd, fileSize-metaEnd); err != nil {
-			return err
-		}
-	case udtaFound && !metaFound:
-		if err := copyRange(output, input, 0, moovHeader.offset); err != nil {
-			return err
-		}
-		if err := writeAtomHeader(output, "moov", newMoovSize, moovHeader.headerSize); err != nil {
-			return err
-		}
-		if err := copyRange(output, input, moovHeader.offset+moovHeader.headerSize, udtaHeader.offset-(moovHeader.offset+moovHeader.headerSize)); err != nil {
-			return err
-		}
-		if err := writeAtomHeader(output, "udta", newUdtaSize, udtaHeader.headerSize); err != nil {
-			return err
-		}
-		insertPos := udtaHeader.offset + udtaHeader.size
-		if err := copyRange(output, input, udtaHeader.offset+udtaHeader.headerSize, insertPos-(udtaHeader.offset+udtaHeader.headerSize)); err != nil {
-			return err
-		}
-		if _, err := output.Write(metaAtom); err != nil {
-			return fmt.Errorf("failed to write meta atom: %w", err)
-		}
-		if err := copyRange(output, input, insertPos, fileSize-insertPos); err != nil {
-			return err
-		}
-	case !udtaFound:
-		newUdtaAtom := buildUdtaAtom(metaAtom)
-		if err := copyRange(output, input, 0, moovHeader.offset); err != nil {
-			return err
-		}
-		if err := writeAtomHeader(output, "moov", newMoovSize, moovHeader.headerSize); err != nil {
-			return err
-		}
-		moovEnd := moovHeader.offset + moovHeader.size
-		if err := copyRange(output, input, moovHeader.offset+moovHeader.headerSize, moovEnd-(moovHeader.offset+moovHeader.headerSize)); err != nil {
-			return err
-		}
-		if _, err := output.Write(newUdtaAtom); err != nil {
-			return fmt.Errorf("failed to write udta atom: %w", err)
-		}
-		if err := copyRange(output, input, moovEnd, fileSize-moovEnd); err != nil {
-			return err
-		}
-	}
-
-	if err := output.Close(); err != nil {
-		return fmt.Errorf("failed to close temp file: %w", err)
-	}
-
-	_ = input.Close()
-	if err := os.Remove(filePath); err != nil {
-		return fmt.Errorf("failed to replace original file: %w", err)
-	}
-	if err := os.Rename(tempPath, filePath); err != nil {
-		return fmt.Errorf("failed to move temp file: %w", err)
-	}
-	cleanupTemp = false
-
-	fmt.Printf("[M4A] Metadata embedded successfully\n")
-	return nil
-}
-
-// buildMetaAtom builds a complete meta atom with ilst containing metadata
-func buildMetaAtom(metadata Metadata, coverData []byte) []byte {
-	var ilst []byte
-
-	if metadata.Title != "" {
-		ilst = append(ilst, buildTextAtom("©nam", metadata.Title)...)
-	}
-
-	if metadata.Artist != "" {
-		ilst = append(ilst, buildTextAtom("©ART", metadata.Artist)...)
-	}
-
-	if metadata.Album != "" {
-		ilst = append(ilst, buildTextAtom("©alb", metadata.Album)...)
-	}
-
-	if metadata.AlbumArtist != "" {
-		ilst = append(ilst, buildTextAtom("aART", metadata.AlbumArtist)...)
-	}
-
-	if metadata.Date != "" {
-		ilst = append(ilst, buildTextAtom("©day", metadata.Date)...)
-	}
-
-	if metadata.TrackNumber > 0 {
-		ilst = append(ilst, buildTrackNumberAtom(metadata.TrackNumber, metadata.TotalTracks)...)
-	}
-
-	if metadata.DiscNumber > 0 {
-		ilst = append(ilst, buildDiscNumberAtom(metadata.DiscNumber, 0)...)
-	}
-
-	if metadata.Lyrics != "" {
-		ilst = append(ilst, buildTextAtom("©lyr", metadata.Lyrics)...)
-	}
-
-	if len(coverData) > 0 {
-		ilst = append(ilst, buildCoverAtom(coverData)...)
-	}
-
-	ilstSize := 8 + len(ilst)
-	ilstAtom := make([]byte, 4)
-	ilstAtom[0] = byte(ilstSize >> 24)
-	ilstAtom[1] = byte(ilstSize >> 16)
-	ilstAtom[2] = byte(ilstSize >> 8)
-	ilstAtom[3] = byte(ilstSize)
-	ilstAtom = append(ilstAtom, []byte("ilst")...)
-	ilstAtom = append(ilstAtom, ilst...)
-
-	hdlr := []byte{
-		0, 0, 0, 33, // size = 33
-		'h', 'd', 'l', 'r',
-		0, 0, 0, 0, // version + flags
-		0, 0, 0, 0, // predefined
-		'm', 'd', 'i', 'r', // handler type
-		'a', 'p', 'p', 'l', // manufacturer
-		0, 0, 0, 0, // component flags
-		0, 0, 0, 0, // component flags mask
-		0, // null terminator
-	}
-
-	metaContent := append([]byte{0, 0, 0, 0}, hdlr...) // version + flags + hdlr
-	metaContent = append(metaContent, ilstAtom...)
-
-	metaSize := 8 + len(metaContent)
-	metaAtom := make([]byte, 4)
-	metaAtom[0] = byte(metaSize >> 24)
-	metaAtom[1] = byte(metaSize >> 16)
-	metaAtom[2] = byte(metaSize >> 8)
-	metaAtom[3] = byte(metaSize)
-	metaAtom = append(metaAtom, []byte("meta")...)
-	metaAtom = append(metaAtom, metaContent...)
-
-	return metaAtom
-}
-
-func buildTextAtom(name, value string) []byte {
-	valueBytes := []byte(value)
-
-	dataSize := 16 + len(valueBytes)
-	dataAtom := make([]byte, 4)
-	dataAtom[0] = byte(dataSize >> 24)
-	dataAtom[1] = byte(dataSize >> 16)
-	dataAtom[2] = byte(dataSize >> 8)
-	dataAtom[3] = byte(dataSize)
-	dataAtom = append(dataAtom, []byte("data")...)
-	dataAtom = append(dataAtom, 0, 0, 0, 1) // type = UTF-8
-	dataAtom = append(dataAtom, 0, 0, 0, 0) // locale
-	dataAtom = append(dataAtom, valueBytes...)
-
-	atomSize := 8 + len(dataAtom)
-	atom := make([]byte, 4)
-	atom[0] = byte(atomSize >> 24)
-	atom[1] = byte(atomSize >> 16)
-	atom[2] = byte(atomSize >> 8)
-	atom[3] = byte(atomSize)
-	atom = append(atom, []byte(name)...)
-	atom = append(atom, dataAtom...)
-
-	return atom
-}
-
-// buildTrackNumberAtom builds trkn atom
-func buildTrackNumberAtom(track, total int) []byte {
-	dataAtom := []byte{
-		0, 0, 0, 24, // size
-		'd', 'a', 't', 'a',
-		0, 0, 0, 0, // type = implicit
-		0, 0, 0, 0, // locale
-		0, 0, // padding
-		byte(track >> 8), byte(track), // track number
-		byte(total >> 8), byte(total), // total tracks
-		0, 0, // padding
-	}
-
-	atomSize := 8 + len(dataAtom)
-	atom := make([]byte, 4)
-	atom[0] = byte(atomSize >> 24)
-	atom[1] = byte(atomSize >> 16)
-	atom[2] = byte(atomSize >> 8)
-	atom[3] = byte(atomSize)
-	atom = append(atom, []byte("trkn")...)
-	atom = append(atom, dataAtom...)
-
-	return atom
-}
-
-func buildDiscNumberAtom(disc, total int) []byte {
-	dataAtom := []byte{
-		0, 0, 0, 22, // size
-		'd', 'a', 't', 'a',
-		0, 0, 0, 0, // type = implicit
-		0, 0, 0, 0, // locale
-		0, 0, // padding
-		byte(disc >> 8), byte(disc), // disc number
-		byte(total >> 8), byte(total), // total discs
-	}
-
-	atomSize := 8 + len(dataAtom)
-	atom := make([]byte, 4)
-	atom[0] = byte(atomSize >> 24)
-	atom[1] = byte(atomSize >> 16)
-	atom[2] = byte(atomSize >> 8)
-	atom[3] = byte(atomSize)
-	atom = append(atom, []byte("disk")...)
-	atom = append(atom, dataAtom...)
-
-	return atom
-}
-
-// buildCoverAtom builds covr atom with image data
-func buildCoverAtom(coverData []byte) []byte {
-	imageType := byte(13)
-	if len(coverData) > 8 && coverData[0] == 0x89 && coverData[1] == 'P' && coverData[2] == 'N' && coverData[3] == 'G' {
-		imageType = 14
-	}
-
-	dataSize := 16 + len(coverData)
-	dataAtom := make([]byte, 4)
-	dataAtom[0] = byte(dataSize >> 24)
-	dataAtom[1] = byte(dataSize >> 16)
-	dataAtom[2] = byte(dataSize >> 8)
-	dataAtom[3] = byte(dataSize)
-	dataAtom = append(dataAtom, []byte("data")...)
-	dataAtom = append(dataAtom, 0, 0, 0, imageType)
-	dataAtom = append(dataAtom, 0, 0, 0, 0)
-	dataAtom = append(dataAtom, coverData...)
-
-	atomSize := 8 + len(dataAtom)
-	atom := make([]byte, 4)
-	atom[0] = byte(atomSize >> 24)
-	atom[1] = byte(atomSize >> 16)
-	atom[2] = byte(atomSize >> 8)
-	atom[3] = byte(atomSize)
-	atom = append(atom, []byte("covr")...)
-	atom = append(atom, dataAtom...)
-
-	return atom
-}
-
 func GetM4AQuality(filePath string) (AudioQuality, error) {
 	f, err := os.Open(filePath)
 	if err != nil {
@@ -974,52 +804,6 @@ func findAtomInRange(f *os.File, start, size int64, target string, fileSize int6
 	return atomHeader{}, false, nil
 }
 
-func writeAtomHeader(w io.Writer, typ string, size int64, headerSize int64) error {
-	if len(typ) != 4 {
-		return fmt.Errorf("invalid atom type: %s", typ)
-	}
-
-	if headerSize == 16 {
-		header := make([]byte, 16)
-		binary.BigEndian.PutUint32(header[0:4], 1)
-		copy(header[4:8], []byte(typ))
-		binary.BigEndian.PutUint64(header[8:16], uint64(size))
-		_, err := w.Write(header)
-		return err
-	}
-
-	if size > int64(^uint32(0)) {
-		return fmt.Errorf("atom size exceeds 32-bit for %s", typ)
-	}
-
-	header := make([]byte, 8)
-	binary.BigEndian.PutUint32(header[0:4], uint32(size))
-	copy(header[4:8], []byte(typ))
-	_, err := w.Write(header)
-	return err
-}
-
-func copyRange(dst io.Writer, src *os.File, offset, length int64) error {
-	if length <= 0 {
-		return nil
-	}
-	if _, err := src.Seek(offset, io.SeekStart); err != nil {
-		return fmt.Errorf("failed to seek source: %w", err)
-	}
-	if _, err := io.CopyN(dst, src, length); err != nil {
-		return fmt.Errorf("failed to copy data: %w", err)
-	}
-	return nil
-}
-
-func buildUdtaAtom(metaAtom []byte) []byte {
-	size := 8 + len(metaAtom)
-	header := make([]byte, 8)
-	binary.BigEndian.PutUint32(header[0:4], uint32(size))
-	copy(header[4:8], []byte("udta"))
-	return append(header, metaAtom...)
-}
-
 func findAudioSampleEntry(f *os.File, start, end, fileSize int64) (int64, string, error) {
 	const chunkSize = 64 * 1024
 	patternMP4A := []byte("mp4a")

go_backend/output_fd.go

@@ -0,0 +1,31 @@
+package gobackend
+
+import (
+	"fmt"
+	"os"
+	"strings"
+)
+
+func isFDOutput(outputFD int) bool {
+	return outputFD > 0
+}
+
+func openOutputForWrite(outputPath string, outputFD int) (*os.File, error) {
+	if isFDOutput(outputFD) {
+		return os.NewFile(uintptr(outputFD), fmt.Sprintf("saf_fd_%d", outputFD)), nil
+	}
+	return os.Create(outputPath)
+}
+
+func cleanupOutputOnError(outputPath string, outputFD int) {
+	if isFDOutput(outputFD) {
+		return
+	}
+
+	path := strings.TrimSpace(outputPath)
+	if path == "" || strings.HasPrefix(path, "/proc/self/fd/") {
+		return
+	}
+
+	_ = os.Remove(path)
+}

go_backend/parallel.go

@@ -1,6 +1,7 @@
 package gobackend
 
 import (
+	"encoding/json"
 	"fmt"
 	"sync"
 	"time"
@@ -9,15 +10,14 @@ import (
 type TrackIDCacheEntry struct {
 	TidalTrackID  int64
 	QobuzTrackID  int64
-	AmazonTrackID string
+	AmazonURL     string
 	ExpiresAt     time.Time
 }
 
 type TrackIDCache struct {
-	cache map[string]*TrackIDCacheEntry
-	mu    sync.RWMutex
-	ttl   time.Duration
-	// Cleanup is triggered on writes at a fixed interval to avoid unbounded growth.
+	cache           map[string]*TrackIDCacheEntry
+	mu              sync.RWMutex
+	ttl             time.Duration
 	lastCleanup     time.Time
 	cleanupInterval time.Duration
 }
@@ -52,7 +52,6 @@ func (c *TrackIDCache) Get(isrc string) *TrackIDCacheEntry {
 		return entry
 	}
 
-	// Lazily delete expired entry.
 	c.mu.Lock()
 	entry, exists = c.cache[isrc]
 	if exists && time.Now().After(entry.ExpiresAt) {
@@ -108,7 +107,7 @@ func (c *TrackIDCache) SetQobuz(isrc string, trackID int64) {
 	}
 }
 
-func (c *TrackIDCache) SetAmazon(isrc string, trackID string) {
+func (c *TrackIDCache) SetAmazonURL(isrc string, amazonURL string) {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 
@@ -117,7 +116,7 @@ func (c *TrackIDCache) SetAmazon(isrc string, trackID string) {
 		entry = &TrackIDCacheEntry{}
 		c.cache[isrc] = entry
 	}
-	entry.AmazonTrackID = trackID
+	entry.AmazonURL = amazonURL
 	now := time.Now()
 	entry.ExpiresAt = now.Add(c.ttl)
 
@@ -139,7 +138,6 @@ func (c *TrackIDCache) Size() int {
 	return len(c.cache)
 }
 
-// ParallelDownloadResult holds results from parallel operations
 type ParallelDownloadResult struct {
 	CoverData  []byte
 	LyricsData *LyricsResponse
@@ -159,20 +157,20 @@ func FetchCoverAndLyricsParallel(
 ) *ParallelDownloadResult {
 	result := &ParallelDownloadResult{}
 	var wg sync.WaitGroup
+	var resultMu sync.Mutex
 
 	if coverURL != "" {
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			fmt.Println("[Parallel] Starting cover download...")
 			data, err := downloadCoverToMemory(coverURL, maxQualityCover)
+			resultMu.Lock()
 			if err != nil {
 				result.CoverErr = err
-				fmt.Printf("[Parallel] Cover download failed: %v\n", err)
 			} else {
 				result.CoverData = data
-				fmt.Printf("[Parallel] Cover downloaded: %d bytes\n", len(data))
 			}
+			resultMu.Unlock()
 		}()
 	}
 
@@ -180,21 +178,19 @@ func FetchCoverAndLyricsParallel(
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			fmt.Println("[Parallel] Starting lyrics fetch...")
 			client := NewLyricsClient()
 			durationSec := float64(durationMs) / 1000.0
 			lyrics, err := client.FetchLyricsAllSources(spotifyID, trackName, artistName, durationSec)
+			resultMu.Lock()
 			if err != nil {
 				result.LyricsErr = err
-				fmt.Printf("[Parallel] Lyrics fetch failed: %v\n", err)
 			} else if lyrics != nil && len(lyrics.Lines) > 0 {
 				result.LyricsData = lyrics
 				result.LyricsLRC = convertToLRCWithMetadata(lyrics, trackName, artistName)
-				fmt.Printf("[Parallel] Lyrics fetched: %d lines\n", len(lyrics.Lines))
 			} else {
 				result.LyricsErr = fmt.Errorf("no lyrics found")
-				fmt.Println("[Parallel] No lyrics found")
 			}
+			resultMu.Unlock()
 		}()
 	}
 
@@ -206,8 +202,8 @@ type PreWarmCacheRequest struct {
 	ISRC       string
 	TrackName  string
 	ArtistName string
-	SpotifyID  string // Needed for Amazon (SongLink lookup)
-	Service    string // "tidal", "qobuz", "amazon"
+	SpotifyID  string
+	Service    string
 }
 
 func PreWarmTrackCache(requests []PreWarmCacheRequest) {
@@ -215,13 +211,15 @@ func PreWarmTrackCache(requests []PreWarmCacheRequest) {
 		return
 	}
 
-	fmt.Printf("[Cache] Pre-warming cache for %d tracks...\n", len(requests))
 	cache := GetTrackIDCache()
 
 	semaphore := make(chan struct{}, 3)
 	var wg sync.WaitGroup
 
 	for _, req := range requests {
+		if req.ISRC == "" {
+			continue
+		}
 		if cached := cache.Get(req.ISRC); cached != nil {
 			continue
 		}
@@ -236,7 +234,7 @@ func PreWarmTrackCache(requests []PreWarmCacheRequest) {
 			case "tidal":
 				preWarmTidalCache(r.ISRC, r.TrackName, r.ArtistName)
 			case "qobuz":
-				preWarmQobuzCache(r.ISRC)
+				preWarmQobuzCache(r.ISRC, r.SpotifyID)
 			case "amazon":
 				preWarmAmazonCache(r.ISRC, r.SpotifyID)
 			}
@@ -244,7 +242,6 @@ func PreWarmTrackCache(requests []PreWarmCacheRequest) {
 	}
 
 	wg.Wait()
-	fmt.Printf("[Cache] Pre-warm complete. Cache size: %d\n", cache.Size())
 }
 
 func preWarmTidalCache(isrc, _, _ string) {
@@ -252,30 +249,68 @@ func preWarmTidalCache(isrc, _, _ string) {
 	track, err := downloader.SearchTrackByISRC(isrc)
 	if err == nil && track != nil {
 		GetTrackIDCache().SetTidal(isrc, track.ID)
-		fmt.Printf("[Cache] Cached Tidal ID for ISRC %s: %d\n", isrc, track.ID)
 	}
 }
 
-func preWarmQobuzCache(isrc string) {
+// preWarmQobuzCache tries to get Qobuz Track ID in the following order:
+// 1. From SongLink (fast, no Qobuz API call needed)
+// 2. Direct ISRC search on Qobuz API (slower, may fail if ISRC not in Qobuz database)
+func preWarmQobuzCache(isrc, spotifyID string) {
+	// First, try to get QobuzID from SongLink - this is faster and more reliable
+	if spotifyID != "" {
+		client := NewSongLinkClient()
+		availability, err := client.CheckTrackAvailability(spotifyID, isrc)
+		if err == nil && availability != nil && availability.QobuzID != "" {
+			// Parse QobuzID to int64
+			var trackID int64
+			if _, parseErr := fmt.Sscanf(availability.QobuzID, "%d", &trackID); parseErr == nil && trackID > 0 {
+				GoLog("[Qobuz] Pre-warm cache: Got Qobuz ID %d from SongLink for ISRC %s\n", trackID, isrc)
+				GetTrackIDCache().SetQobuz(isrc, trackID)
+				return
+			}
+		}
+	}
+
+	// Fallback: Direct ISRC search on Qobuz API
 	downloader := NewQobuzDownloader()
 	track, err := downloader.SearchTrackByISRC(isrc)
 	if err == nil && track != nil {
+		GoLog("[Qobuz] Pre-warm cache: Got Qobuz ID %d from direct ISRC search for %s\n", track.ID, isrc)
 		GetTrackIDCache().SetQobuz(isrc, track.ID)
-		fmt.Printf("[Cache] Cached Qobuz ID for ISRC %s: %d\n", isrc, track.ID)
 	}
 }
 
 func preWarmAmazonCache(isrc, spotifyID string) {
 	client := NewSongLinkClient()
 	availability, err := client.CheckTrackAvailability(spotifyID, isrc)
-	if err == nil && availability != nil && availability.Amazon {
-		GetTrackIDCache().SetAmazon(isrc, availability.AmazonURL)
-		fmt.Printf("[Cache] Cached Amazon URL for ISRC %s\n", isrc)
+	if err == nil && availability != nil && availability.AmazonURL != "" {
+		GetTrackIDCache().SetAmazonURL(isrc, availability.AmazonURL)
 	}
 }
 
 func PreWarmCache(tracksJSON string) error {
-	var requests []PreWarmCacheRequest
+	var tracks []struct {
+		ISRC       string `json:"isrc"`
+		TrackName  string `json:"track_name"`
+		ArtistName string `json:"artist_name"`
+		SpotifyID  string `json:"spotify_id"`
+		Service    string `json:"service"`
+	}
+
+	if err := json.Unmarshal([]byte(tracksJSON), &tracks); err != nil {
+		return fmt.Errorf("failed to parse tracks JSON: %w", err)
+	}
+
+	requests := make([]PreWarmCacheRequest, len(tracks))
+	for i, t := range tracks {
+		requests[i] = PreWarmCacheRequest{
+			ISRC:       t.ISRC,
+			TrackName:  t.TrackName,
+			ArtistName: t.ArtistName,
+			SpotifyID:  t.SpotifyID,
+			Service:    t.Service,
+		}
+	}
 
 	go PreWarmTrackCache(requests)
 	return nil
@@ -283,7 +318,6 @@ func PreWarmCache(tracksJSON string) error {
 
 func ClearTrackCache() {
 	GetTrackIDCache().Clear()
-	fmt.Println("[Cache] Track ID cache cleared")
 }
 
 func GetCacheSize() int {

go_backend/progress.go

@@ -78,7 +78,6 @@ func GetItemProgress(itemID string) string {
 	return "{}"
 }
 
-// StartItemProgress initializes progress tracking for an item
 func StartItemProgress(itemID string) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -93,7 +92,6 @@ func StartItemProgress(itemID string) {
 	}
 }
 
-// SetItemBytesTotal sets total bytes for an item
 func SetItemBytesTotal(itemID string, total int64) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -103,7 +101,6 @@ func SetItemBytesTotal(itemID string, total int64) {
 	}
 }
 
-// SetItemBytesReceived sets bytes received for an item
 func SetItemBytesReceived(itemID string, received int64) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -116,7 +113,6 @@ func SetItemBytesReceived(itemID string, received int64) {
 	}
 }
 
-// SetItemBytesReceivedWithSpeed sets bytes received and speed for an item
 func SetItemBytesReceivedWithSpeed(itemID string, received int64, speedMBps float64) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -130,7 +126,6 @@ func SetItemBytesReceivedWithSpeed(itemID string, received int64, speedMBps floa
 	}
 }
 
-// CompleteItemProgress marks an item as complete
 func CompleteItemProgress(itemID string) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -142,7 +137,6 @@ func CompleteItemProgress(itemID string) {
 	}
 }
 
-// SetItemProgress sets progress for an item directly
 func SetItemProgress(itemID string, progress float64, bytesReceived, bytesTotal int64) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -158,7 +152,6 @@ func SetItemProgress(itemID string, progress float64, bytesReceived, bytesTotal
 	}
 }
 
-// SetItemFinalizing marks an item as finalizing (embedding metadata)
 func SetItemFinalizing(itemID string) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -169,7 +162,6 @@ func SetItemFinalizing(itemID string) {
 	}
 }
 
-// RemoveItemProgress removes progress tracking for an item
 func RemoveItemProgress(itemID string) {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -177,7 +169,6 @@ func RemoveItemProgress(itemID string) {
 	delete(multiProgress.Items, itemID)
 }
 
-// ClearAllItemProgress clears all item progress
 func ClearAllItemProgress() {
 	multiMu.Lock()
 	defer multiMu.Unlock()
@@ -185,7 +176,6 @@ func ClearAllItemProgress() {
 	multiProgress.Items = make(map[string]*ItemProgress)
 }
 
-// setDownloadDir sets the default download directory
 func setDownloadDir(path string) error {
 	downloadDirMu.Lock()
 	defer downloadDirMu.Unlock()
@@ -193,20 +183,18 @@ func setDownloadDir(path string) error {
 	return nil
 }
 
-// ItemProgressWriter wraps io.Writer to track download progress for a specific item
 type ItemProgressWriter struct {
 	writer       interface{ Write([]byte) (int, error) }
 	itemID       string
 	current      int64
-	lastReported int64     // Track last reported bytes for threshold-based updates
-	startTime    time.Time // Track start time for speed calculation
-	lastTime     time.Time // Track last update time for speed calculation
-	lastBytes    int64     // Track bytes at last speed calculation
+	lastReported int64
+	startTime    time.Time
+	lastTime     time.Time
+	lastBytes    int64
 }
 
-const progressUpdateThreshold = 64 * 1024 // Update progress every 64KB
+const progressUpdateThreshold = 64 * 1024
 
-// NewItemProgressWriter creates a new progress writer for a specific item
 func NewItemProgressWriter(w interface{ Write([]byte) (int, error) }, itemID string) *ItemProgressWriter {
 	now := time.Now()
 	return &ItemProgressWriter{
@@ -220,7 +208,6 @@ func NewItemProgressWriter(w interface{ Write([]byte) (int, error) }, itemID str
 	}
 }
 
-// Write implements io.Writer with threshold-based progress updates and speed tracking
 func (pw *ItemProgressWriter) Write(p []byte) (int, error) {
 	if pw.itemID != "" && isDownloadCancelled(pw.itemID) {
 		return 0, ErrDownloadCancelled

go_backend/qobuz.go

@@ -52,12 +52,10 @@ func qobuzArtistsMatch(expectedArtist, foundArtist string) bool {
 	normExpected := strings.ToLower(strings.TrimSpace(expectedArtist))
 	normFound := strings.ToLower(strings.TrimSpace(foundArtist))
 
-	// Exact match
 	if normExpected == normFound {
 		return true
 	}
 
-	// Check if one contains the other
 	if strings.Contains(normExpected, normFound) || strings.Contains(normFound, normExpected) {
 		return true
 	}
@@ -112,24 +110,19 @@ func qobuzSplitArtists(artists string) []string {
 	return result
 }
 
-// qobuzSameWordsUnordered checks if two strings have the same words regardless of order
-// Useful for Japanese names: "Sawano Hiroyuki" vs "Hiroyuki Sawano"
 func qobuzSameWordsUnordered(a, b string) bool {
 	wordsA := strings.Fields(a)
 	wordsB := strings.Fields(b)
 
-	// Must have same number of words
 	if len(wordsA) != len(wordsB) || len(wordsA) == 0 {
 		return false
 	}
 
-	// Sort and compare
 	sortedA := make([]string, len(wordsA))
 	sortedB := make([]string, len(wordsB))
 	copy(sortedA, wordsA)
 	copy(sortedB, wordsB)
 
-	// Simple bubble sort (usually just 2-3 words)
 	for i := 0; i < len(sortedA)-1; i++ {
 		for j := i + 1; j < len(sortedA); j++ {
 			if sortedA[i] > sortedA[j] {
@@ -153,7 +146,6 @@ func qobuzTitlesMatch(expectedTitle, foundTitle string) bool {
 	normExpected := strings.ToLower(strings.TrimSpace(expectedTitle))
 	normFound := strings.ToLower(strings.TrimSpace(foundTitle))
 
-	// Exact match
 	if normExpected == normFound {
 		return true
 	}
@@ -182,8 +174,6 @@ func qobuzTitlesMatch(expectedTitle, foundTitle string) bool {
 		return true
 	}
 
-	// If scripts are TRULY different (Latin vs CJK/Arabic/Cyrillic), assume match (transliteration)
-	// Don't treat Latin Extended (Polish, French, etc.) as different script
 	expectedLatin := qobuzIsLatinScript(expectedTitle)
 	foundLatin := qobuzIsLatinScript(foundTitle)
 	if expectedLatin != foundLatin {
@@ -194,9 +184,7 @@ func qobuzTitlesMatch(expectedTitle, foundTitle string) bool {
 	return false
 }
 
-// qobuzExtractCoreTitle extracts the main title before any parentheses or brackets
 func qobuzExtractCoreTitle(title string) string {
-	// Find first occurrence of ( or [
 	parenIdx := strings.Index(title, "(")
 	bracketIdx := strings.Index(title, "[")
 	dashIdx := strings.Index(title, " - ")
@@ -281,49 +269,28 @@ func qobuzCleanTitle(title string) string {
 	return strings.TrimSpace(cleaned)
 }
 
-// qobuzIsLatinScript checks if a string is primarily Latin script
-// Returns true for ASCII and Latin Extended characters (European languages)
-// Returns false for CJK, Arabic, Cyrillic, etc.
 func qobuzIsLatinScript(s string) bool {
 	for _, r := range s {
-		// Skip common punctuation and numbers
 		if r < 128 {
 			continue
 		}
-		// Latin Extended-A: U+0100 to U+017F (Polish, Czech, etc.)
-		// Latin Extended-B: U+0180 to U+024F
-		// Latin Extended Additional: U+1E00 to U+1EFF
-		// Latin Extended-C/D/E: various ranges
-		if (r >= 0x0100 && r <= 0x024F) || // Latin Extended A & B
-			(r >= 0x1E00 && r <= 0x1EFF) || // Latin Extended Additional
-			(r >= 0x00C0 && r <= 0x00FF) { // Latin-1 Supplement (accented chars)
+		if (r >= 0x0100 && r <= 0x024F) ||
+			(r >= 0x1E00 && r <= 0x1EFF) ||
+			(r >= 0x00C0 && r <= 0x00FF) {
 			continue
 		}
-		// CJK ranges - definitely different script
-		if (r >= 0x4E00 && r <= 0x9FFF) || // CJK Unified Ideographs
-			(r >= 0x3040 && r <= 0x309F) || // Hiragana
-			(r >= 0x30A0 && r <= 0x30FF) || // Katakana
-			(r >= 0xAC00 && r <= 0xD7AF) || // Hangul (Korean)
-			(r >= 0x0600 && r <= 0x06FF) || // Arabic
-			(r >= 0x0400 && r <= 0x04FF) { // Cyrillic
+		if (r >= 0x4E00 && r <= 0x9FFF) ||
+			(r >= 0x3040 && r <= 0x309F) ||
+			(r >= 0x30A0 && r <= 0x30FF) ||
+			(r >= 0xAC00 && r <= 0xD7AF) ||
+			(r >= 0x0600 && r <= 0x06FF) ||
+			(r >= 0x0400 && r <= 0x04FF) {
 			return false
 		}
 	}
 	return true
 }
 
-// qobuzIsASCIIString checks if a string contains only ASCII characters
-// Kept for potential future use
-// func qobuzIsASCIIString(s string) bool {
-// 	for _, r := range s {
-// 		if r > 127 {
-// 			return false
-// 		}
-// 	}
-// 	return true
-// }
-
-// containsQueryQobuz checks if a query already exists in the list
 func containsQueryQobuz(queries []string, query string) bool {
 	for _, q := range queries {
 		if q == query {
@@ -336,7 +303,7 @@ func containsQueryQobuz(queries []string, query string) bool {
 func NewQobuzDownloader() *QobuzDownloader {
 	qobuzDownloaderOnce.Do(func() {
 		globalQobuzDownloader = &QobuzDownloader{
-			client: NewHTTPClientWithTimeout(DefaultTimeout), // 60s timeout
+			client: NewHTTPClientWithTimeout(DefaultTimeout),
 			appID:  "798273057",
 		}
 	})
@@ -344,7 +311,6 @@ func NewQobuzDownloader() *QobuzDownloader {
 }
 
 func (q *QobuzDownloader) GetTrackByID(trackID int64) (*QobuzTrack, error) {
-	// Qobuz API: /track/get?track_id=XXX
 	apiBase, _ := base64.StdEncoding.DecodeString("aHR0cHM6Ly93d3cucW9idXouY29tL2FwaS5qc29uLzAuMi90cmFjay9nZXQ/dHJhY2tfaWQ9")
 	trackURL := fmt.Sprintf("%s%d&app_id=%s", string(apiBase), trackID, q.appID)
 
@@ -371,15 +337,11 @@ func (q *QobuzDownloader) GetTrackByID(trackID int64) (*QobuzTrack, error) {
 	return &track, nil
 }
 
-// GetAvailableAPIs returns list of available Qobuz APIs
-// Uses same APIs as PC version for compatibility
 func (q *QobuzDownloader) GetAvailableAPIs() []string {
-	// Same APIs as PC version (referensi/backend/qobuz.go)
-	// Primary: dab.yeet.su, Fallback: dabmusic.xyz, qobuz.squid.wtf
 	encodedAPIs := []string{
-		"ZGFiLnllZXQuc3UvYXBpL3N0cmVhbT90cmFja0lkPQ==",                 // dab.yeet.su/api/stream?trackId=
-		"ZGFibXVzaWMueHl6L2FwaS9zdHJlYW0/dHJhY2tJZD0=",                 // dabmusic.xyz/api/stream?trackId=
-		"cW9idXouc3F1aWQud3RmL2FwaS9kb3dubG9hZC1tdXNpYz90cmFja19pZD0=", // qobuz.squid.wtf/api/download-music?track_id=
+		"ZGFiLnllZXQuc3UvYXBpL3N0cmVhbT90cmFja0lkPQ==",
+		"ZGFibXVzaWMueHl6L2FwaS9zdHJlYW0/dHJhY2tJZD0=",
+		"cW9idXouc3F1aWQud3RmL2FwaS9kb3dubG9hZC1tdXNpYz90cmFja19pZD0=",
 	}
 
 	var apis []string
@@ -394,21 +356,19 @@ func (q *QobuzDownloader) GetAvailableAPIs() []string {
 	return apis
 }
 
-// mapJumoQuality maps Qobuz quality codes to Jumo format
 func mapJumoQuality(quality string) int {
 	switch quality {
 	case "6":
-		return 6 // 16-bit FLAC
+		return 6
 	case "7":
-		return 7 // 24-bit 96kHz
+		return 7
 	case "27":
-		return 27 // 24-bit 192kHz
+		return 27
 	default:
 		return 6
 	}
 }
 
-// decodeXOR decodes XOR-encoded response from Jumo API
 func decodeXOR(data []byte) string {
 	text := string(data)
 	runes := []rune(text)
@@ -420,13 +380,46 @@ func decodeXOR(data []byte) string {
 	return string(result)
 }
 
-// downloadFromJumo gets download URL from Jumo API (fallback)
+func extractQobuzDownloadURLFromBody(body []byte) (string, error) {
+	var raw map[string]any
+	if err := json.Unmarshal(body, &raw); err != nil {
+		return "", fmt.Errorf("invalid JSON: %v", err)
+	}
+
+	if errMsg, ok := raw["error"].(string); ok && strings.TrimSpace(errMsg) != "" {
+		return "", fmt.Errorf("%s", errMsg)
+	}
+
+	if success, ok := raw["success"].(bool); ok && !success {
+		if msg, ok := raw["message"].(string); ok && strings.TrimSpace(msg) != "" {
+			return "", fmt.Errorf("%s", msg)
+		}
+		return "", fmt.Errorf("api returned success=false")
+	}
+
+	if urlVal, ok := raw["url"].(string); ok && strings.TrimSpace(urlVal) != "" {
+		return strings.TrimSpace(urlVal), nil
+	}
+	if linkVal, ok := raw["link"].(string); ok && strings.TrimSpace(linkVal) != "" {
+		return strings.TrimSpace(linkVal), nil
+	}
+
+	if data, ok := raw["data"].(map[string]any); ok {
+		if urlVal, ok := data["url"].(string); ok && strings.TrimSpace(urlVal) != "" {
+			return strings.TrimSpace(urlVal), nil
+		}
+		if linkVal, ok := data["link"].(string); ok && strings.TrimSpace(linkVal) != "" {
+			return strings.TrimSpace(linkVal), nil
+		}
+	}
+
+	return "", fmt.Errorf("no download URL in response")
+}
+
 func (q *QobuzDownloader) downloadFromJumo(trackID int64, quality string) (string, error) {
 	formatID := mapJumoQuality(quality)
 	region := "US"
-
-	// Jumo API endpoint
-	jumoURL := fmt.Sprintf("https://jumo-dl.pages.dev/file?track_id=%d&format_id=%d&region=%s", trackID, formatID, region)
+	jumoURL := fmt.Sprintf("https://jumo-dl.pages.dev/get?track_id=%d&format_id=%d&region=%s", trackID, formatID, region)
 
 	GoLog("[Qobuz] Trying Jumo API fallback...\n")
 
@@ -435,6 +428,8 @@ func (q *QobuzDownloader) downloadFromJumo(trackID int64, quality string) (strin
 	if err != nil {
 		return "", err
 	}
+	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("Referer", "https://jumo-dl.pages.dev/")
 
 	resp, err := client.Do(req)
 	if err != nil {
@@ -452,17 +447,13 @@ func (q *QobuzDownloader) downloadFromJumo(trackID int64, quality string) (strin
 	}
 
 	var result map[string]any
-
-	// Try parsing as plain JSON first
 	if err := json.Unmarshal(body, &result); err != nil {
-		// Try XOR decoding
 		decoded := decodeXOR(body)
 		if err := json.Unmarshal([]byte(decoded), &result); err != nil {
 			return "", fmt.Errorf("failed to parse Jumo response (plain or XOR): %w", err)
 		}
 	}
 
-	// Check for URL in various response formats
 	if urlVal, ok := result["url"].(string); ok && urlVal != "" {
 		GoLog("[Qobuz] Jumo API returned URL successfully\n")
 		return urlVal, nil
@@ -511,7 +502,6 @@ func (q *QobuzDownloader) SearchTrackByISRC(isrc string) (*QobuzTrack, error) {
 		return nil, err
 	}
 
-	// Find exact ISRC match
 	for i := range result.Tracks.Items {
 		if result.Tracks.Items[i].ISRC == isrc {
 			return &result.Tracks.Items[i], nil
@@ -525,7 +515,6 @@ func (q *QobuzDownloader) SearchTrackByISRC(isrc string) (*QobuzTrack, error) {
 	return nil, fmt.Errorf("no exact ISRC match found for: %s", isrc)
 }
 
-// expectedDurationSec is the expected duration in seconds (0 to skip verification)
 func (q *QobuzDownloader) SearchTrackByISRCWithDuration(isrc string, expectedDurationSec int) (*QobuzTrack, error) {
 	GoLog("[Qobuz] Searching by ISRC: %s\n", isrc)
 
@@ -558,7 +547,6 @@ func (q *QobuzDownloader) SearchTrackByISRCWithDuration(isrc string, expectedDur
 
 	GoLog("[Qobuz] ISRC search returned %d results\n", len(result.Tracks.Items))
 
-	// Find ISRC matches
 	var isrcMatches []*QobuzTrack
 	for i := range result.Tracks.Items {
 		if result.Tracks.Items[i].ISRC == isrc {
@@ -612,35 +600,26 @@ func (q *QobuzDownloader) SearchTrackByMetadata(trackName, artistName string) (*
 	return q.SearchTrackByMetadataWithDuration(trackName, artistName, 0)
 }
 
-// Now includes romaji conversion for Japanese text (same as Tidal)
-// Also includes title verification to prevent wrong song downloads
 func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistName string, expectedDurationSec int) (*QobuzTrack, error) {
 	apiBase, _ := base64.StdEncoding.DecodeString("aHR0cHM6Ly93d3cucW9idXouY29tL2FwaS5qc29uLzAuMi90cmFjay9zZWFyY2g/cXVlcnk9")
 
-	// Try multiple search strategies (same as Tidal/PC version)
 	queries := []string{}
 
-	// Strategy 1: Artist + Track name
 	if artistName != "" && trackName != "" {
 		queries = append(queries, artistName+" "+trackName)
 	}
 
-	// Strategy 2: Track name only
 	if trackName != "" {
 		queries = append(queries, trackName)
 	}
 
-	// Strategy 3: Romaji versions if Japanese detected
 	if ContainsJapanese(trackName) || ContainsJapanese(artistName) {
-		// Convert to romaji (hiragana/katakana only, kanji stays)
 		romajiTrack := JapaneseToRomaji(trackName)
 		romajiArtist := JapaneseToRomaji(artistName)
 
-		// Clean and remove ALL non-ASCII characters (including kanji)
 		cleanRomajiTrack := CleanToASCII(romajiTrack)
 		cleanRomajiArtist := CleanToASCII(romajiArtist)
 
-		// Artist + Track romaji (cleaned to ASCII only)
 		if cleanRomajiArtist != "" && cleanRomajiTrack != "" {
 			romajiQuery := cleanRomajiArtist + " " + cleanRomajiTrack
 			if !containsQueryQobuz(queries, romajiQuery) {
@@ -649,7 +628,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 			}
 		}
 
-		// Track romaji only (cleaned)
 		if cleanRomajiTrack != "" && cleanRomajiTrack != trackName {
 			if !containsQueryQobuz(queries, cleanRomajiTrack) {
 				queries = append(queries, cleanRomajiTrack)
@@ -657,7 +635,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 		}
 	}
 
-	// Strategy 4: Artist only as last resort
 	if artistName != "" {
 		artistOnly := CleanToASCII(JapaneseToRomaji(artistName))
 		if artistOnly != "" && !containsQueryQobuz(queries, artistOnly) {
@@ -716,7 +693,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 		return nil, fmt.Errorf("no tracks found for: %s - %s", artistName, trackName)
 	}
 
-	// Filter by title match first (NEW - like Tidal)
 	var titleMatches []*QobuzTrack
 	for i := range allTracks {
 		track := &allTracks[i]
@@ -727,7 +703,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 
 	GoLog("[Qobuz] Title matches: %d out of %d results\n", len(titleMatches), len(allTracks))
 
-	// If no title matches, log warning but continue with all tracks
 	tracksToCheck := titleMatches
 	if len(titleMatches) == 0 {
 		GoLog("[Qobuz] WARNING: No title matches for '%s', checking all %d results\n", trackName, len(allTracks))
@@ -736,7 +711,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 		}
 	}
 
-	// If duration verification is requested
 	if expectedDurationSec > 0 {
 		var durationMatches []*QobuzTrack
 		for _, track := range tracksToCheck {
@@ -765,7 +739,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 		return nil, fmt.Errorf("no tracks found with matching title and duration (expected '%s', %ds)", trackName, expectedDurationSec)
 	}
 
-	// No duration verification, return best quality from title matches
 	for _, track := range tracksToCheck {
 		if track.MaximumBitDepth >= 24 {
 			GoLog("[Qobuz] Match found: '%s' by '%s' (title verified, hi-res)\n",
@@ -783,7 +756,6 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 	return nil, fmt.Errorf("no matching track found for: %s - %s", artistName, trackName)
 }
 
-// qobuzAPIResult holds the result from a parallel API request
 type qobuzAPIResult struct {
 	apiURL      string
 	downloadURL string
@@ -791,82 +763,154 @@ type qobuzAPIResult struct {
 	duration    time.Duration
 }
 
+// Qobuz API timeout configuration
+// Mobile networks are more unstable, so we use longer timeouts
+const (
+	qobuzAPITimeoutMobile = 25 * time.Second
+	qobuzMaxRetries       = 2 // Number of retries per API
+	qobuzRetryDelay       = 500 * time.Millisecond
+)
+
+// getQobuzAPITimeout returns appropriate timeout based on platform
+// For mobile (gomobile builds), we use longer timeouts
+func getQobuzAPITimeout() time.Duration {
+	// Since this runs in gomobile context, we always use mobile timeout
+	// The Go backend is only used on mobile (Android/iOS)
+	return qobuzAPITimeoutMobile
+}
+
+// qobuzSquidCountries defines the region fallback order for squid.wtf API
+var qobuzSquidCountries = []string{"US", "FR"}
+
+// fetchQobuzURLWithRetry fetches download URL from a single Qobuz API with retry logic
+// For squid.wtf APIs, it tries US region first, then falls back to FR
+func fetchQobuzURLWithRetry(api string, trackID int64, quality string, timeout time.Duration) (string, error) {
+	isSquid := strings.Contains(api, "squid.wtf")
+
+	if isSquid {
+		for _, country := range qobuzSquidCountries {
+			GoLog("[Qobuz] Trying squid.wtf with country=%s\n", country)
+			result, err := fetchQobuzURLSingleAttempt(api, trackID, quality, timeout, country)
+			if err == nil {
+				return result, nil
+			}
+			GoLog("[Qobuz] squid.wtf country=%s failed: %v\n", country, err)
+		}
+		return "", fmt.Errorf("squid.wtf failed for all regions (US, FR)")
+	}
+
+	return fetchQobuzURLSingleAttempt(api, trackID, quality, timeout, "")
+}
+
+// fetchQobuzURLSingleAttempt fetches download URL with retry logic for a single API+country combination
+func fetchQobuzURLSingleAttempt(api string, trackID int64, quality string, timeout time.Duration, country string) (string, error) {
+	var lastErr error
+	retryDelay := qobuzRetryDelay
+
+	for attempt := 0; attempt <= qobuzMaxRetries; attempt++ {
+		if attempt > 0 {
+			GoLog("[Qobuz] Retry %d/%d for %s after %v\n", attempt, qobuzMaxRetries, api, retryDelay)
+			time.Sleep(retryDelay)
+			retryDelay *= 2 // Exponential backoff
+		}
+
+		client := NewHTTPClientWithTimeout(timeout)
+		reqURL := fmt.Sprintf("%s%d&quality=%s", api, trackID, quality)
+		if country != "" {
+			reqURL += "&country=" + country
+		}
+
+		req, err := http.NewRequest("GET", reqURL, nil)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+
+		resp, err := client.Do(req)
+		if err != nil {
+			lastErr = err
+			// Check for retryable errors (timeout, connection reset)
+			errStr := strings.ToLower(err.Error())
+			if strings.Contains(errStr, "timeout") ||
+				strings.Contains(errStr, "reset") ||
+				strings.Contains(errStr, "connection refused") ||
+				strings.Contains(errStr, "eof") {
+				continue // Retry
+			}
+			break // Non-retryable error
+		}
+		// Server errors are retryable
+		if resp.StatusCode >= 500 {
+			io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			lastErr = fmt.Errorf("HTTP %d", resp.StatusCode)
+			continue
+		}
+
+		// 429 rate limit - wait and retry
+		if resp.StatusCode == 429 {
+			io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			lastErr = fmt.Errorf("rate limited")
+			retryDelay = 2 * time.Second // Wait longer for rate limit
+			continue
+		}
+
+		if resp.StatusCode != 200 {
+			io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			return "", fmt.Errorf("HTTP %d", resp.StatusCode)
+		}
+
+		body, err := io.ReadAll(resp.Body)
+		resp.Body.Close()
+		if err != nil {
+			lastErr = err
+			continue
+		}
+
+		if len(body) > 0 && body[0] == '<' {
+			return "", fmt.Errorf("received HTML instead of JSON")
+		}
+
+		urlVal, parseErr := extractQobuzDownloadURLFromBody(body)
+		if parseErr == nil {
+			return urlVal, nil
+		}
+		lastErr = parseErr
+		continue
+	}
+
+	if lastErr != nil {
+		return "", lastErr
+	}
+	return "", fmt.Errorf("all retries failed")
+}
+
 func getQobuzDownloadURLParallel(apis []string, trackID int64, quality string) (string, string, error) {
 	if len(apis) == 0 {
 		return "", "", fmt.Errorf("no APIs available")
 	}
 
-	GoLog("[Qobuz] Requesting download URL from %d APIs in parallel...\n", len(apis))
+	GoLog("[Qobuz] Requesting download URL from %d APIs in parallel (with retry)...\n", len(apis))
 
 	resultChan := make(chan qobuzAPIResult, len(apis))
 	startTime := time.Now()
+	timeout := getQobuzAPITimeout()
 
-	// Start all requests in parallel
 	for _, apiURL := range apis {
 		go func(api string) {
 			reqStart := time.Now()
-
-			client := NewHTTPClientWithTimeout(15 * time.Second)
-
-			reqURL := fmt.Sprintf("%s%d&quality=%s", api, trackID, quality)
-
-			req, err := http.NewRequest("GET", reqURL, nil)
-			if err != nil {
-				resultChan <- qobuzAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-				return
+			downloadURL, err := fetchQobuzURLWithRetry(api, trackID, quality, timeout)
+			resultChan <- qobuzAPIResult{
+				apiURL:      api,
+				downloadURL: downloadURL,
+				err:         err,
+				duration:    time.Since(reqStart),
 			}
-
-			resp, err := client.Do(req)
-			if err != nil {
-				resultChan <- qobuzAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-				return
-			}
-			defer resp.Body.Close()
-
-			if resp.StatusCode != 200 {
-				resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("HTTP %d", resp.StatusCode), duration: time.Since(reqStart)}
-				return
-			}
-
-			body, err := io.ReadAll(resp.Body)
-			if err != nil {
-				resultChan <- qobuzAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-				return
-			}
-
-			// Check if response is HTML (error page)
-			if len(body) > 0 && body[0] == '<' {
-				resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("received HTML instead of JSON"), duration: time.Since(reqStart)}
-				return
-			}
-
-			// Check for error in JSON response
-			var errorResp struct {
-				Error string `json:"error"`
-			}
-			if json.Unmarshal(body, &errorResp) == nil && errorResp.Error != "" {
-				resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("%s", errorResp.Error), duration: time.Since(reqStart)}
-				return
-			}
-
-			var result struct {
-				URL string `json:"url"`
-			}
-			if err := json.Unmarshal(body, &result); err != nil {
-				resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("invalid JSON: %v", err), duration: time.Since(reqStart)}
-				return
-			}
-
-			if result.URL != "" {
-				resultChan <- qobuzAPIResult{apiURL: api, downloadURL: result.URL, err: nil, duration: time.Since(reqStart)}
-				return
-			}
-
-			resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("no download URL in response"), duration: time.Since(reqStart)}
 		}(apiURL)
 	}
 
-	// Collect results - return first success
 	var errors []string
 
 	for i := 0; i < len(apis); i++ {
@@ -874,7 +918,6 @@ func getQobuzDownloadURLParallel(apis []string, trackID int64, quality string) (
 		if result.err == nil {
 			GoLog("[Qobuz] [Parallel] Got response from %s in %v\n", result.apiURL, result.duration)
 
-			// Drain remaining results to avoid goroutine leaks
 			go func(remaining int) {
 				for j := 0; j < remaining; j++ {
 					<-resultChan
@@ -906,14 +949,12 @@ func (q *QobuzDownloader) GetDownloadURL(trackID int64, quality string) (string,
 		return downloadURL, nil
 	}
 
-	// All standard APIs failed, try Jumo as fallback
 	GoLog("[Qobuz] Standard APIs failed, trying Jumo fallback...\n")
 	jumoURL, jumoErr := q.downloadFromJumo(trackID, quality)
 	if jumoErr == nil {
 		return jumoURL, nil
 	}
 
-	// If quality is 27 (hi-res), try fallback to lower quality
 	if quality == "27" {
 		GoLog("[Qobuz] Hi-res (27) failed, trying 24-bit (7)...\n")
 		jumoURL, jumoErr = q.downloadFromJumo(trackID, "7")
@@ -933,11 +974,9 @@ func (q *QobuzDownloader) GetDownloadURL(trackID int64, quality string) (string,
 	return "", fmt.Errorf("all Qobuz APIs and Jumo fallback failed: %w", err)
 }
 
-// DownloadFile downloads a file from URL with User-Agent and progress tracking
-func (q *QobuzDownloader) DownloadFile(downloadURL, outputPath, itemID string) error {
+func (q *QobuzDownloader) DownloadFile(downloadURL, outputPath string, outputFD int, itemID string) error {
 	ctx := context.Background()
 
-	// Initialize item progress (required for all downloads)
 	if itemID != "" {
 		StartItemProgress(itemID)
 		defer CompleteItemProgress(itemID)
@@ -972,7 +1011,7 @@ func (q *QobuzDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 		SetItemBytesTotal(itemID, expectedSize)
 	}
 
-	out, err := os.Create(outputPath)
+	out, err := openOutputForWrite(outputPath, outputFD)
 	if err != nil {
 		return err
 	}
@@ -987,29 +1026,27 @@ func (q *QobuzDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 		written, err = io.Copy(bufWriter, resp.Body)
 	}
 
-	// Flush buffer before checking for errors
 	flushErr := bufWriter.Flush()
 	closeErr := out.Close()
 
 	if err != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		if isDownloadCancelled(itemID) {
 			return ErrDownloadCancelled
 		}
 		return fmt.Errorf("download interrupted: %w", err)
 	}
 	if flushErr != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("failed to flush buffer: %w", flushErr)
 	}
 	if closeErr != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("failed to close file: %w", closeErr)
 	}
 
-	// Verify file size if Content-Length was provided
 	if expectedSize > 0 && written != expectedSize {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("incomplete download: expected %d bytes, got %d bytes", expectedSize, written)
 	}
 
@@ -1027,13 +1064,17 @@ type QobuzDownloadResult struct {
 	TrackNumber int
 	DiscNumber  int
 	ISRC        string
+	LyricsLRC   string
 }
 
 func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 	downloader := NewQobuzDownloader()
 
-	if existingFile, exists := checkISRCExistsInternal(req.OutputDir, req.ISRC); exists {
-		return QobuzDownloadResult{FilePath: "EXISTS:" + existingFile}, nil
+	isSafOutput := isFDOutput(req.OutputFD) || strings.TrimSpace(req.OutputPath) != ""
+	if !isSafOutput {
+		if existingFile, exists := checkISRCExistsInternal(req.OutputDir, req.ISRC); exists {
+			return QobuzDownloadResult{FilePath: "EXISTS:" + existingFile}, nil
+		}
 	}
 
 	expectedDurationSec := req.DurationMS / 1000
@@ -1041,6 +1082,7 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 	var track *QobuzTrack
 	var err error
 
+	// Strategy 1: Use Qobuz ID from Odesli enrichment (fastest, most accurate)
 	if req.QobuzID != "" {
 		GoLog("[Qobuz] Using Qobuz ID from Odesli enrichment: %s\n", req.QobuzID)
 		var trackID int64
@@ -1055,24 +1097,46 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		}
 	}
 
-	// OPTIMIZATION: Check cache first for track ID
+	// Strategy 2: Use cached Qobuz Track ID (fast, no search needed)
 	if track == nil && req.ISRC != "" {
 		if cached := GetTrackIDCache().Get(req.ISRC); cached != nil && cached.QobuzTrackID > 0 {
 			GoLog("[Qobuz] Cache hit! Using cached track ID: %d\n", cached.QobuzTrackID)
-			// For Qobuz we need to search again to get full track info, but we can use the ID
-			track, err = downloader.SearchTrackByISRC(req.ISRC)
+			track, err = downloader.GetTrackByID(cached.QobuzTrackID)
 			if err != nil {
-				GoLog("[Qobuz] Cache hit but search failed: %v\n", err)
+				GoLog("[Qobuz] Cache hit but GetTrackByID failed: %v\n", err)
 				track = nil
 			}
 		}
 	}
 
-	// Strategy 1: Search by ISRC with duration verification
+	// Strategy 3: Try to get QobuzID from SongLink if we have SpotifyID
+	if track == nil && req.SpotifyID != "" && req.QobuzID == "" {
+		GoLog("[Qobuz] Trying to get Qobuz ID from SongLink for Spotify ID: %s\n", req.SpotifyID)
+		songLinkClient := NewSongLinkClient()
+		availability, slErr := songLinkClient.CheckTrackAvailability(req.SpotifyID, req.ISRC)
+		if slErr == nil && availability != nil && availability.QobuzID != "" {
+			var trackID int64
+			if _, parseErr := fmt.Sscanf(availability.QobuzID, "%d", &trackID); parseErr == nil && trackID > 0 {
+				GoLog("[Qobuz] Got Qobuz ID %d from SongLink\n", trackID)
+				track, err = downloader.GetTrackByID(trackID)
+				if err != nil {
+					GoLog("[Qobuz] Failed to get track by SongLink ID %d: %v\n", trackID, err)
+					track = nil
+				} else if track != nil {
+					GoLog("[Qobuz] Successfully found track via SongLink ID: '%s' by '%s'\n", track.Title, track.Performer.Name)
+					// Cache for future use
+					if req.ISRC != "" {
+						GetTrackIDCache().SetQobuz(req.ISRC, track.ID)
+					}
+				}
+			}
+		}
+	}
+
+	// Strategy 4: ISRC search with duration verification
 	if track == nil && req.ISRC != "" {
 		GoLog("[Qobuz] Trying ISRC search: %s\n", req.ISRC)
 		track, err = downloader.SearchTrackByISRCWithDuration(req.ISRC, expectedDurationSec)
-		// Verify artist AND title
 		if track != nil {
 			if !qobuzArtistsMatch(req.ArtistName, track.Performer.Name) {
 				GoLog("[Qobuz] Artist mismatch from ISRC search: expected '%s', got '%s'. Rejecting.\n",
@@ -1086,10 +1150,10 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		}
 	}
 
-	// Strategy 2: Search by metadata with duration verification (includes title verification)
+	// Strategy 5: Metadata search with strict matching (duration tolerance: 10 seconds)
 	if track == nil {
+		GoLog("[Qobuz] Trying metadata search: '%s' by '%s'\n", req.TrackName, req.ArtistName)
 		track, err = downloader.SearchTrackByMetadataWithDuration(req.TrackName, req.ArtistName, expectedDurationSec)
-		// Verify artist (title already verified in SearchTrackByMetadataWithDuration)
 		if track != nil && !qobuzArtistsMatch(req.ArtistName, track.Performer.Name) {
 			GoLog("[Qobuz] Artist mismatch from metadata search: expected '%s', got '%s'. Rejecting.\n",
 				req.ArtistName, track.Performer.Name)
@@ -1105,7 +1169,6 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		return QobuzDownloadResult{}, fmt.Errorf("qobuz search failed: %s", errMsg)
 	}
 
-	// Log match found and cache the track ID
 	GoLog("[Qobuz] Match found: '%s' by '%s' (duration: %ds)\n", track.Title, track.Performer.Name, track.Duration)
 	if req.ISRC != "" {
 		GetTrackIDCache().SetQobuz(req.ISRC, track.ID)
@@ -1117,31 +1180,36 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		"album":  req.AlbumName,
 		"track":  req.TrackNumber,
 		"year":   extractYear(req.ReleaseDate),
+		"date":   req.ReleaseDate,
 		"disc":   req.DiscNumber,
 	})
-	filename = sanitizeFilename(filename) + ".flac"
-	outputPath := filepath.Join(req.OutputDir, filename)
-
-	if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
-		return QobuzDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
+	var outputPath string
+	if isSafOutput {
+		outputPath = strings.TrimSpace(req.OutputPath)
+		if outputPath == "" && isFDOutput(req.OutputFD) {
+			outputPath = fmt.Sprintf("/proc/self/fd/%d", req.OutputFD)
+		}
+	} else {
+		filename = sanitizeFilename(filename) + ".flac"
+		outputPath = filepath.Join(req.OutputDir, filename)
+		if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
+			return QobuzDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
+		}
 	}
 
-	// Map quality from Tidal format to Qobuz format
-	// Tidal: LOSSLESS (16-bit), HI_RES (24-bit), HI_RES_LOSSLESS (24-bit hi-res)
-	// Qobuz: 5 (MP3 320), 6 (16-bit), 7 (24-bit 96kHz), 27 (24-bit 192kHz)
-	qobuzQuality := "27" // Default to highest quality
+	qobuzQuality := "27"
 	switch req.Quality {
 	case "LOSSLESS":
-		qobuzQuality = "6" // 16-bit FLAC
+		qobuzQuality = "6"
 	case "HI_RES":
-		qobuzQuality = "7" // 24-bit 96kHz
+		qobuzQuality = "7"
 	case "HI_RES_LOSSLESS":
-		qobuzQuality = "27" // 24-bit 192kHz
+		qobuzQuality = "27"
 	}
 	GoLog("[Qobuz] Using quality: %s (mapped from %s)\n", qobuzQuality, req.Quality)
 
 	actualBitDepth := track.MaximumBitDepth
-	actualSampleRate := int(track.MaximumSamplingRate * 1000) // Convert kHz to Hz
+	actualSampleRate := int(track.MaximumSamplingRate * 1000)
 	GoLog("[Qobuz] Actual quality: %d-bit/%.1fkHz\n", actualBitDepth, track.MaximumSamplingRate)
 
 	downloadURL, err := downloader.GetDownloadURL(track.ID, qobuzQuality)
@@ -1149,7 +1217,6 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		return QobuzDownloadResult{}, fmt.Errorf("failed to get download URL: %w", err)
 	}
 
-	// START PARALLEL: Fetch cover and lyrics while downloading audio
 	var parallelResult *ParallelDownloadResult
 	parallelDone := make(chan struct{})
 	go func() {
@@ -1165,15 +1232,13 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		)
 	}()
 
-	// Download audio file with item ID for progress tracking
-	if err := downloader.DownloadFile(downloadURL, outputPath, req.ItemID); err != nil {
+	if err := downloader.DownloadFile(downloadURL, outputPath, req.OutputFD, req.ItemID); err != nil {
 		if errors.Is(err, ErrDownloadCancelled) {
 			return QobuzDownloadResult{}, ErrDownloadCancelled
 		}
 		return QobuzDownloadResult{}, fmt.Errorf("download failed: %w", err)
 	}
 
-	// Wait for parallel operations to complete
 	<-parallelDone
 
 	if req.ItemID != "" {
@@ -1186,7 +1251,6 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		albumName = req.AlbumName
 	}
 
-	// Use track number from request if available, otherwise from Qobuz API
 	actualTrackNumber := req.TrackNumber
 	if actualTrackNumber == 0 {
 		actualTrackNumber = track.TrackNumber
@@ -1196,15 +1260,15 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		Title:       track.Title,
 		Artist:      track.Performer.Name,
 		Album:       albumName,
-		AlbumArtist: req.AlbumArtist, // Qobuz track struct might not have this handy, keep req or check album struct
+		AlbumArtist: req.AlbumArtist,
 		Date:        track.Album.ReleaseDate,
 		TrackNumber: actualTrackNumber,
 		TotalTracks: req.TotalTracks,
-		DiscNumber:  req.DiscNumber, // QobuzTrack struct usually doesn't have disc info in simple search result
+		DiscNumber:  req.DiscNumber,
 		ISRC:        track.ISRC,
-		Genre:       req.Genre,     // From Deezer album metadata
-		Label:       req.Label,     // From Deezer album metadata
-		Copyright:   req.Copyright, // From Deezer album metadata
+		Genre:       req.Genre,
+		Label:       req.Label,
+		Copyright:   req.Copyright,
 	}
 
 	var coverData []byte
@@ -1213,40 +1277,50 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		GoLog("[Qobuz] Using parallel-fetched cover (%d bytes)\n", len(coverData))
 	}
 
-	if err := EmbedMetadataWithCoverData(outputPath, metadata, coverData); err != nil {
-		fmt.Printf("Warning: failed to embed metadata: %v\n", err)
+	if isSafOutput {
+		GoLog("[Qobuz] SAF output detected - skipping in-backend metadata/lyrics embedding (handled in Flutter)\n")
+	} else {
+		if err := EmbedMetadataWithCoverData(outputPath, metadata, coverData); err != nil {
+			fmt.Printf("Warning: failed to embed metadata: %v\n", err)
+		}
+
+		if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
+			lyricsMode := req.LyricsMode
+			if lyricsMode == "" {
+				lyricsMode = "embed"
+			}
+
+			if lyricsMode == "external" || lyricsMode == "both" {
+				GoLog("[Qobuz] Saving external LRC file...\n")
+				if lrcPath, lrcErr := SaveLRCFile(outputPath, parallelResult.LyricsLRC); lrcErr != nil {
+					GoLog("[Qobuz] Warning: failed to save LRC file: %v\n", lrcErr)
+				} else {
+					GoLog("[Qobuz] LRC file saved: %s\n", lrcPath)
+				}
+			}
+
+			if lyricsMode == "embed" || lyricsMode == "both" {
+				GoLog("[Qobuz] Embedding parallel-fetched lyrics (%d lines)...\n", len(parallelResult.LyricsData.Lines))
+				if embedErr := EmbedLyrics(outputPath, parallelResult.LyricsLRC); embedErr != nil {
+					GoLog("[Qobuz] Warning: failed to embed lyrics: %v\n", embedErr)
+				} else {
+					fmt.Println("[Qobuz] Lyrics embedded successfully")
+				}
+			}
+		} else if req.EmbedLyrics {
+			fmt.Println("[Qobuz] No lyrics available from parallel fetch")
+		}
 	}
 
+	if !isSafOutput {
+		AddToISRCIndex(req.OutputDir, req.ISRC, outputPath)
+	}
+
+	lyricsLRC := ""
 	if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
-		lyricsMode := req.LyricsMode
-		if lyricsMode == "" {
-			lyricsMode = "embed"
-		}
-
-		if lyricsMode == "external" || lyricsMode == "both" {
-			GoLog("[Qobuz] Saving external LRC file...\n")
-			if lrcPath, lrcErr := SaveLRCFile(outputPath, parallelResult.LyricsLRC); lrcErr != nil {
-				GoLog("[Qobuz] Warning: failed to save LRC file: %v\n", lrcErr)
-			} else {
-				GoLog("[Qobuz] LRC file saved: %s\n", lrcPath)
-			}
-		}
-
-		if lyricsMode == "embed" || lyricsMode == "both" {
-			GoLog("[Qobuz] Embedding parallel-fetched lyrics (%d lines)...\n", len(parallelResult.LyricsData.Lines))
-			if embedErr := EmbedLyrics(outputPath, parallelResult.LyricsLRC); embedErr != nil {
-				GoLog("[Qobuz] Warning: failed to embed lyrics: %v\n", embedErr)
-			} else {
-				fmt.Println("[Qobuz] Lyrics embedded successfully")
-			}
-		}
-	} else if req.EmbedLyrics {
-		fmt.Println("[Qobuz] No lyrics available from parallel fetch")
+		lyricsLRC = parallelResult.LyricsLRC
 	}
 
-	// Add to ISRC index for fast duplicate checking
-	AddToISRCIndex(req.OutputDir, req.ISRC, outputPath)
-
 	return QobuzDownloadResult{
 		FilePath:    outputPath,
 		BitDepth:    actualBitDepth,
@@ -1256,7 +1330,8 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 		Album:       track.Album.Title,
 		ReleaseDate: track.Album.ReleaseDate,
 		TrackNumber: actualTrackNumber,
-		DiscNumber:  req.DiscNumber, // Qobuz track struct limitations
+		DiscNumber:  req.DiscNumber,
 		ISRC:        track.ISRC,
+		LyricsLRC:   lyricsLRC,
 	}, nil
 }

go_backend/qobuz_test.go

@@ -0,0 +1,47 @@
+package gobackend
+
+import "testing"
+
+func TestExtractQobuzDownloadURLFromBody(t *testing.T) {
+	t.Run("reads nested data.url", func(t *testing.T) {
+		body := []byte(`{"success":true,"data":{"url":"https://example.test/audio.flac"}}`)
+
+		got, err := extractQobuzDownloadURLFromBody(body)
+		if err != nil {
+			t.Fatalf("expected no error, got %v", err)
+		}
+		if got != "https://example.test/audio.flac" {
+			t.Fatalf("unexpected URL: %q", got)
+		}
+	})
+
+	t.Run("reads top-level url", func(t *testing.T) {
+		body := []byte(`{"url":"https://example.test/top.flac"}`)
+
+		got, err := extractQobuzDownloadURLFromBody(body)
+		if err != nil {
+			t.Fatalf("expected no error, got %v", err)
+		}
+		if got != "https://example.test/top.flac" {
+			t.Fatalf("unexpected URL: %q", got)
+		}
+	})
+
+	t.Run("returns API error", func(t *testing.T) {
+		body := []byte(`{"error":"track not found"}`)
+
+		_, err := extractQobuzDownloadURLFromBody(body)
+		if err == nil || err.Error() != "track not found" {
+			t.Fatalf("expected track-not-found error, got %v", err)
+		}
+	})
+
+	t.Run("returns message when success false", func(t *testing.T) {
+		body := []byte(`{"success":false,"message":"blocked"}`)
+
+		_, err := extractQobuzDownloadURLFromBody(body)
+		if err == nil || err.Error() != "blocked" {
+			t.Fatalf("expected blocked error, got %v", err)
+		}
+	})
+}

go_backend/security_hardening_test.go

@@ -0,0 +1,80 @@
+package gobackend
+
+import (
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+func TestSanitizeSensitiveLogText(t *testing.T) {
+	input := "access_token=abc123 Authorization:Bearer xyz456 https://api.example.com/cb?refresh_token=zzz"
+	redacted := sanitizeSensitiveLogText(input)
+
+	if strings.Contains(redacted, "abc123") || strings.Contains(redacted, "xyz456") || strings.Contains(redacted, "zzz") {
+		t.Fatalf("expected sensitive values to be redacted, got: %s", redacted)
+	}
+	if !strings.Contains(redacted, "[REDACTED]") {
+		t.Fatalf("expected redaction marker in output, got: %s", redacted)
+	}
+}
+
+func TestValidateExtensionAuthURL(t *testing.T) {
+	if err := validateExtensionAuthURL("https://accounts.example.com/oauth/authorize"); err != nil {
+		t.Fatalf("expected valid auth URL, got error: %v", err)
+	}
+
+	blocked := []string{
+		"http://accounts.example.com/oauth/authorize",
+		"https://user:pass@accounts.example.com/oauth/authorize",
+		"https://localhost/oauth/authorize",
+	}
+
+	for _, rawURL := range blocked {
+		if err := validateExtensionAuthURL(rawURL); err == nil {
+			t.Fatalf("expected URL to be blocked: %s", rawURL)
+		}
+	}
+}
+
+func TestValidateDomainRejectsEmbeddedCredentials(t *testing.T) {
+	ext := &LoadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+			Permissions: ExtensionPermissions{
+				Network: []string{"api.example.com"},
+			},
+		},
+		DataDir: t.TempDir(),
+	}
+
+	runtime := NewExtensionRuntime(ext)
+	if err := runtime.validateDomain("https://user:pass@api.example.com/resource"); err == nil {
+		t.Fatal("expected embedded URL credentials to be rejected")
+	}
+}
+
+func TestBuildStoreExtensionDestPath(t *testing.T) {
+	baseDir := t.TempDir()
+
+	destPath, err := buildStoreExtensionDestPath(baseDir, "../evil/name")
+	if err != nil {
+		t.Fatalf("expected sanitized path to be generated, got error: %v", err)
+	}
+
+	if !isPathWithinBase(baseDir, destPath) {
+		t.Fatalf("expected destination path to remain under base dir: %s", destPath)
+	}
+
+	baseName := filepath.Base(destPath)
+	if strings.Contains(baseName, "/") || strings.Contains(baseName, `\`) {
+		t.Fatalf("expected filename to be sanitized, got: %s", baseName)
+	}
+	if !strings.HasSuffix(baseName, ".spotiflac-ext") {
+		t.Fatalf("expected .spotiflac-ext suffix, got: %s", baseName)
+	}
+
+	if _, err := buildStoreExtensionDestPath(baseDir, "   "); err == nil {
+		t.Fatal("expected empty extension id to be rejected")
+	}
+}

go_backend/songlink.go

@@ -8,7 +8,6 @@ import (
 	"net/url"
 	"strings"
 	"sync"
-	"time"
 )
 
 type SongLinkClient struct {
@@ -16,16 +15,21 @@ type SongLinkClient struct {
 }
 
 type TrackAvailability struct {
-	SpotifyID string `json:"spotify_id"`
-	Tidal     bool   `json:"tidal"`
-	Amazon    bool   `json:"amazon"`
-	Qobuz     bool   `json:"qobuz"`
-	Deezer    bool   `json:"deezer"`
-	TidalURL  string `json:"tidal_url,omitempty"`
-	AmazonURL string `json:"amazon_url,omitempty"`
-	QobuzURL  string `json:"qobuz_url,omitempty"`
-	DeezerURL string `json:"deezer_url,omitempty"`
-	DeezerID  string `json:"deezer_id,omitempty"`
+	SpotifyID  string `json:"spotify_id"`
+	Tidal      bool   `json:"tidal"`
+	Amazon     bool   `json:"amazon"`
+	Qobuz      bool   `json:"qobuz"`
+	Deezer     bool   `json:"deezer"`
+	YouTube    bool   `json:"youtube"`
+	TidalURL   string `json:"tidal_url,omitempty"`
+	AmazonURL  string `json:"amazon_url,omitempty"`
+	QobuzURL   string `json:"qobuz_url,omitempty"`
+	DeezerURL  string `json:"deezer_url,omitempty"`
+	YouTubeURL string `json:"youtube_url,omitempty"`
+	DeezerID   string `json:"deezer_id,omitempty"`
+	QobuzID    string `json:"qobuz_id,omitempty"`
+	TidalID    string `json:"tidal_id,omitempty"`
+	YouTubeID  string `json:"youtube_id,omitempty"`
 }
 
 var (
@@ -36,40 +40,13 @@ var (
 func NewSongLinkClient() *SongLinkClient {
 	songLinkClientOnce.Do(func() {
 		globalSongLinkClient = &SongLinkClient{
-			client: NewHTTPClientWithTimeout(SongLinkTimeout),
+			client: NewMetadataHTTPClient(SongLinkTimeout),
 		}
 	})
 	return globalSongLinkClient
 }
 
 func (s *SongLinkClient) CheckTrackAvailability(spotifyTrackID string, isrc string) (*TrackAvailability, error) {
-	if spotifyTrackID == "" {
-		return nil, fmt.Errorf("spotify track ID is empty")
-	}
-
-	// Try SongLink first
-	availability, err := s.checkTrackAvailabilitySongLink(spotifyTrackID)
-	if err != nil {
-		// Fallback to IDHS if SongLink fails
-		LogWarn("SongLink", "SongLink failed, trying IDHS fallback: %v", err)
-		idhsClient := NewIDHSClient()
-		availability, err = idhsClient.GetAvailabilityFromSpotify(spotifyTrackID)
-		if err != nil {
-			return nil, fmt.Errorf("both SongLink and IDHS failed: %w", err)
-		}
-		LogInfo("SongLink", "IDHS fallback successful for %s", spotifyTrackID)
-	}
-
-	// Check Qobuz availability separately via ISRC
-	if isrc != "" {
-		availability.Qobuz = checkQobuzAvailability(isrc)
-	}
-
-	return availability, nil
-}
-
-// checkTrackAvailabilitySongLink is the original SongLink implementation
-func (s *SongLinkClient) checkTrackAvailabilitySongLink(spotifyTrackID string) (*TrackAvailability, error) {
 	songLinkRateLimiter.WaitForSlot()
 
 	spotifyBase, _ := base64.StdEncoding.DecodeString("aHR0cHM6Ly9vcGVuLnNwb3RpZnkuY29tL3RyYWNrLw==")
@@ -125,6 +102,7 @@ func (s *SongLinkClient) checkTrackAvailabilitySongLink(spotifyTrackID string) (
 	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
 		availability.Tidal = true
 		availability.TidalURL = tidalLink.URL
+		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
 	}
 
 	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
@@ -138,6 +116,28 @@ func (s *SongLinkClient) checkTrackAvailabilitySongLink(spotifyTrackID string) (
 		availability.DeezerID = extractDeezerIDFromURL(deezerLink.URL)
 	}
 
+	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
+		availability.Qobuz = true
+		availability.QobuzURL = qobuzLink.URL
+		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
+	}
+
+	// Prefer youtubeMusic URLs — they bypass Cobalt login requirements
+	if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
+		availability.YouTube = true
+		availability.YouTubeURL = ytMusicLink.URL
+		availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
+	}
+
+	// Fallback to regular youtube if youtubeMusic not available
+	if !availability.YouTube {
+		if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
+			availability.YouTube = true
+			availability.YouTubeURL = youtubeLink.URL
+			availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
+		}
+	}
+
 	return availability, nil
 }
 
@@ -158,40 +158,6 @@ func (s *SongLinkClient) GetStreamingURLs(spotifyTrackID string) (map[string]str
 	return urls, nil
 }
 
-func checkQobuzAvailability(isrc string) bool {
-	client := NewHTTPClientWithTimeout(10 * time.Second)
-	appID := "798273057"
-
-	apiBase, _ := base64.StdEncoding.DecodeString("aHR0cHM6Ly93d3cucW9idXouY29tL2FwaS5qc29uLzAuMi90cmFjay9zZWFyY2g/cXVlcnk9")
-	searchURL := fmt.Sprintf("%s%s&limit=1&app_id=%s", string(apiBase), isrc, appID)
-
-	req, err := http.NewRequest("GET", searchURL, nil)
-	if err != nil {
-		return false
-	}
-
-	resp, err := DoRequestWithUserAgent(client, req)
-	if err != nil {
-		return false
-	}
-	defer resp.Body.Close()
-
-	if resp.StatusCode != 200 {
-		return false
-	}
-
-	var searchResp struct {
-		Tracks struct {
-			Total int `json:"total"`
-		} `json:"tracks"`
-	}
-	if err := json.NewDecoder(resp.Body).Decode(&searchResp); err != nil {
-		return false
-	}
-
-	return searchResp.Tracks.Total > 0
-}
-
 // extractDeezerIDFromURL extracts Deezer track/album/artist ID from URL
 func extractDeezerIDFromURL(deezerURL string) string {
 	parts := strings.Split(deezerURL, "/")
@@ -205,6 +171,148 @@ func extractDeezerIDFromURL(deezerURL string) string {
 	return ""
 }
 
+// extractQobuzIDFromURL extracts Qobuz track ID from URL
+// URL formats:
+//   - https://www.qobuz.com/us-en/album/.../12345678 (album page with track highlight)
+//   - https://open.qobuz.com/track/12345678
+//   - https://www.qobuz.com/track/12345678
+//   - https://play.qobuz.com/track/12345678
+func extractQobuzIDFromURL(qobuzURL string) string {
+	if qobuzURL == "" {
+		return ""
+	}
+
+	// Try to find /track/ID pattern first
+	if strings.Contains(qobuzURL, "/track/") {
+		parts := strings.Split(qobuzURL, "/track/")
+		if len(parts) > 1 {
+			idPart := parts[1]
+			// Remove query parameters
+			if idx := strings.Index(idPart, "?"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			// Remove trailing slash or path
+			if idx := strings.Index(idPart, "/"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			idPart = strings.TrimSpace(idPart)
+			// Validate it's a number
+			if idPart != "" && isNumeric(idPart) {
+				return idPart
+			}
+		}
+	}
+
+	// Try to extract from album URL with track highlight
+	// Format: /album/albumname/trackid or ?trackId=12345678
+	if strings.Contains(qobuzURL, "trackId=") {
+		parts := strings.Split(qobuzURL, "trackId=")
+		if len(parts) > 1 {
+			idPart := parts[1]
+			if idx := strings.Index(idPart, "&"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			idPart = strings.TrimSpace(idPart)
+			if idPart != "" && isNumeric(idPart) {
+				return idPart
+			}
+		}
+	}
+
+	// Last resort: get last numeric segment from URL
+	parts := strings.Split(qobuzURL, "/")
+	for i := len(parts) - 1; i >= 0; i-- {
+		part := parts[i]
+		// Remove query parameters
+		if idx := strings.Index(part, "?"); idx > 0 {
+			part = part[:idx]
+		}
+		part = strings.TrimSpace(part)
+		if part != "" && isNumeric(part) {
+			return part
+		}
+	}
+
+	return ""
+}
+
+// extractTidalIDFromURL extracts Tidal track ID from URL
+// URL formats:
+//   - https://tidal.com/browse/track/12345678
+//   - https://listen.tidal.com/track/12345678
+func extractTidalIDFromURL(tidalURL string) string {
+	if tidalURL == "" {
+		return ""
+	}
+
+	if strings.Contains(tidalURL, "/track/") {
+		parts := strings.Split(tidalURL, "/track/")
+		if len(parts) > 1 {
+			idPart := parts[1]
+			if idx := strings.Index(idPart, "?"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			if idx := strings.Index(idPart, "/"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			idPart = strings.TrimSpace(idPart)
+			if idPart != "" && isNumeric(idPart) {
+				return idPart
+			}
+		}
+	}
+
+	return ""
+}
+
+// extractYouTubeIDFromURL extracts YouTube video ID from URL
+// URL formats:
+//   - https://www.youtube.com/watch?v=VIDEO_ID
+//   - https://youtu.be/VIDEO_ID
+//   - https://music.youtube.com/watch?v=VIDEO_ID
+func extractYouTubeIDFromURL(youtubeURL string) string {
+	if youtubeURL == "" {
+		return ""
+	}
+
+	// Handle youtu.be short URLs
+	if strings.Contains(youtubeURL, "youtu.be/") {
+		parts := strings.Split(youtubeURL, "youtu.be/")
+		if len(parts) >= 2 {
+			idPart := parts[1]
+			if idx := strings.Index(idPart, "?"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			if idx := strings.Index(idPart, "&"); idx > 0 {
+				idPart = idPart[:idx]
+			}
+			return strings.TrimSpace(idPart)
+		}
+	}
+
+	// Handle youtube.com URLs with ?v= parameter
+	parsed, err := url.Parse(youtubeURL)
+	if err != nil {
+		return ""
+	}
+
+	if v := parsed.Query().Get("v"); v != "" {
+		return v
+	}
+
+	// Handle /embed/ format
+	if strings.Contains(parsed.Path, "/embed/") {
+		parts := strings.Split(parsed.Path, "/embed/")
+		if len(parts) >= 2 {
+			return strings.Split(parts[1], "/")[0]
+		}
+	}
+
+	return ""
+}
+
+// isNumeric is defined in library_scan.go
+
 func (s *SongLinkClient) GetDeezerIDFromSpotify(spotifyTrackID string) (string, error) {
 	availability, err := s.CheckTrackAvailability(spotifyTrackID, "")
 	if err != nil {
@@ -218,6 +326,20 @@ func (s *SongLinkClient) GetDeezerIDFromSpotify(spotifyTrackID string) (string,
 	return availability.DeezerID, nil
 }
 
+// GetYouTubeURLFromSpotify converts a Spotify track ID to YouTube URL using SongLink
+func (s *SongLinkClient) GetYouTubeURLFromSpotify(spotifyTrackID string) (string, error) {
+	availability, err := s.CheckTrackAvailability(spotifyTrackID, "")
+	if err != nil {
+		return "", err
+	}
+
+	if !availability.YouTube || availability.YouTubeURL == "" {
+		return "", fmt.Errorf("track not found on YouTube")
+	}
+
+	return availability.YouTubeURL, nil
+}
+
 // AlbumAvailability represents album availability on different platforms
 type AlbumAvailability struct {
 	SpotifyID string `json:"spotify_id"`
@@ -227,10 +349,8 @@ type AlbumAvailability struct {
 }
 
 func (s *SongLinkClient) CheckAlbumAvailability(spotifyAlbumID string) (*AlbumAvailability, error) {
-	// Use global rate limiter
 	songLinkRateLimiter.WaitForSlot()
 
-	// Build API URL for album
 	spotifyBase, _ := base64.StdEncoding.DecodeString("aHR0cHM6Ly9vcGVuLnNwb3RpZnkuY29tL2FsYnVtLw==")
 	spotifyURL := fmt.Sprintf("%s%s", string(spotifyBase), spotifyAlbumID)
 
@@ -301,10 +421,8 @@ func (s *SongLinkClient) CheckAvailabilityFromDeezer(deezerTrackID string) (*Tra
 		return nil, fmt.Errorf("deezer track ID is empty")
 	}
 
-	// Try SongLink first
 	availability, err := s.checkAvailabilityFromDeezerSongLink(deezerTrackID)
 	if err != nil {
-		// Fallback to IDHS if SongLink fails
 		LogWarn("SongLink", "SongLink failed for Deezer, trying IDHS fallback: %v", err)
 		idhsClient := NewIDHSClient()
 		availability, err = idhsClient.GetAvailabilityFromDeezer(deezerTrackID)
@@ -338,7 +456,6 @@ func (s *SongLinkClient) checkAvailabilityFromDeezerSongLink(deezerTrackID strin
 	}
 	defer resp.Body.Close()
 
-	// Handle specific error codes
 	if resp.StatusCode == 400 {
 		return nil, fmt.Errorf("track not found on SongLink (invalid Deezer ID)")
 	}
@@ -385,6 +502,7 @@ func (s *SongLinkClient) checkAvailabilityFromDeezerSongLink(deezerTrackID strin
 	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
 		availability.Tidal = true
 		availability.TidalURL = tidalLink.URL
+		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
 	}
 
 	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
@@ -392,10 +510,29 @@ func (s *SongLinkClient) checkAvailabilityFromDeezerSongLink(deezerTrackID strin
 		availability.AmazonURL = amazonLink.URL
 	}
 
+	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
+		availability.Qobuz = true
+		availability.QobuzURL = qobuzLink.URL
+		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
+	}
+
 	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
 		availability.DeezerURL = deezerLink.URL
 	}
 
+	if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
+		availability.YouTube = true
+		availability.YouTubeURL = youtubeLink.URL
+		availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
+	}
+	if !availability.YouTube {
+		if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
+			availability.YouTube = true
+			availability.YouTubeURL = ytMusicLink.URL
+			availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
+		}
+	}
+
 	return availability, nil
 }
 
@@ -407,11 +544,8 @@ func (s *SongLinkClient) CheckAvailabilityByPlatform(platform, entityType, entit
 		return nil, fmt.Errorf("%s ID is empty", platform)
 	}
 
-	// Use global rate limiter
 	songLinkRateLimiter.WaitForSlot()
 
-	// Build API URL using platform, type, and id parameters (as per API docs)
-	// https://api.song.link/v1-alpha.1/links?platform=deezer&type=song&id=123456
 	apiURL := fmt.Sprintf("https://api.song.link/v1-alpha.1/links?platform=%s&type=%s&id=%s&userCountry=US",
 		url.QueryEscape(platform),
 		url.QueryEscape(entityType),
@@ -429,7 +563,6 @@ func (s *SongLinkClient) CheckAvailabilityByPlatform(platform, entityType, entit
 	}
 	defer resp.Body.Close()
 
-	// Handle specific error codes
 	if resp.StatusCode == 400 {
 		return nil, fmt.Errorf("track not found on SongLink (invalid %s ID)", platform)
 	}
@@ -467,6 +600,7 @@ func (s *SongLinkClient) CheckAvailabilityByPlatform(platform, entityType, entit
 	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
 		availability.Tidal = true
 		availability.TidalURL = tidalLink.URL
+		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
 	}
 
 	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
@@ -474,12 +608,31 @@ func (s *SongLinkClient) CheckAvailabilityByPlatform(platform, entityType, entit
 		availability.AmazonURL = amazonLink.URL
 	}
 
+	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
+		availability.Qobuz = true
+		availability.QobuzURL = qobuzLink.URL
+		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
+	}
+
 	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
 		availability.Deezer = true
 		availability.DeezerURL = deezerLink.URL
 		availability.DeezerID = extractDeezerIDFromURL(deezerLink.URL)
 	}
 
+	if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
+		availability.YouTube = true
+		availability.YouTubeURL = youtubeLink.URL
+		availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
+	}
+	if !availability.YouTube {
+		if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
+			availability.YouTube = true
+			availability.YouTubeURL = ytMusicLink.URL
+			availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
+		}
+	}
+
 	return availability, nil
 }
 
@@ -535,3 +688,101 @@ func (s *SongLinkClient) GetAmazonURLFromDeezer(deezerTrackID string) (string, e
 
 	return availability.AmazonURL, nil
 }
+
+// GetYouTubeURLFromDeezer converts a Deezer track ID to YouTube URL using SongLink
+func (s *SongLinkClient) GetYouTubeURLFromDeezer(deezerTrackID string) (string, error) {
+	availability, err := s.CheckAvailabilityFromDeezer(deezerTrackID)
+	if err != nil {
+		return "", err
+	}
+
+	if !availability.YouTube || availability.YouTubeURL == "" {
+		return "", fmt.Errorf("track not found on YouTube")
+	}
+
+	return availability.YouTubeURL, nil
+}
+
+func (s *SongLinkClient) CheckAvailabilityFromURL(inputURL string) (*TrackAvailability, error) {
+	songLinkRateLimiter.WaitForSlot()
+
+	apiBase, _ := base64.StdEncoding.DecodeString("aHR0cHM6Ly9hcGkuc29uZy5saW5rL3YxLWFscGhhLjEvbGlua3M/dXJsPQ==")
+	apiURL := fmt.Sprintf("%s%s", string(apiBase), url.QueryEscape(inputURL))
+
+	req, err := http.NewRequest("GET", apiURL, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create request: %w", err)
+	}
+
+	retryConfig := DefaultRetryConfig()
+	resp, err := DoRequestWithRetry(s.client, req, retryConfig)
+	if err != nil {
+		return nil, fmt.Errorf("failed to check availability: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == 400 || resp.StatusCode == 404 {
+		return nil, fmt.Errorf("track not found on SongLink")
+	}
+	if resp.StatusCode == 429 {
+		return nil, fmt.Errorf("SongLink rate limit exceeded")
+	}
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("SongLink API returned status %d", resp.StatusCode)
+	}
+
+	body, err := ReadResponseBody(resp)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response: %w", err)
+	}
+
+	var songLinkResp struct {
+		LinksByPlatform map[string]struct {
+			URL      string `json:"url"`
+			EntityID string `json:"entityUniqueId"`
+		} `json:"linksByPlatform"`
+	}
+
+	if err := json.Unmarshal(body, &songLinkResp); err != nil {
+		return nil, fmt.Errorf("failed to decode response: %w", err)
+	}
+
+	availability := &TrackAvailability{}
+
+	if spotifyLink, ok := songLinkResp.LinksByPlatform["spotify"]; ok && spotifyLink.URL != "" {
+		availability.SpotifyID = extractSpotifyIDFromURL(spotifyLink.URL)
+	}
+	if tidalLink, ok := songLinkResp.LinksByPlatform["tidal"]; ok && tidalLink.URL != "" {
+		availability.Tidal = true
+		availability.TidalURL = tidalLink.URL
+		availability.TidalID = extractTidalIDFromURL(tidalLink.URL)
+	}
+	if amazonLink, ok := songLinkResp.LinksByPlatform["amazonMusic"]; ok && amazonLink.URL != "" {
+		availability.Amazon = true
+		availability.AmazonURL = amazonLink.URL
+	}
+	if qobuzLink, ok := songLinkResp.LinksByPlatform["qobuz"]; ok && qobuzLink.URL != "" {
+		availability.Qobuz = true
+		availability.QobuzURL = qobuzLink.URL
+		availability.QobuzID = extractQobuzIDFromURL(qobuzLink.URL)
+	}
+	if deezerLink, ok := songLinkResp.LinksByPlatform["deezer"]; ok && deezerLink.URL != "" {
+		availability.Deezer = true
+		availability.DeezerURL = deezerLink.URL
+		availability.DeezerID = extractDeezerIDFromURL(deezerLink.URL)
+	}
+	if youtubeLink, ok := songLinkResp.LinksByPlatform["youtube"]; ok && youtubeLink.URL != "" {
+		availability.YouTube = true
+		availability.YouTubeURL = youtubeLink.URL
+		availability.YouTubeID = extractYouTubeIDFromURL(youtubeLink.URL)
+	}
+	if !availability.YouTube {
+		if ytMusicLink, ok := songLinkResp.LinksByPlatform["youtubeMusic"]; ok && ytMusicLink.URL != "" {
+			availability.YouTube = true
+			availability.YouTubeURL = ytMusicLink.URL
+			availability.YouTubeID = extractYouTubeIDFromURL(ytMusicLink.URL)
+		}
+	}
+
+	return availability, nil
+}

go_backend/spotfetch_api.go

@@ -0,0 +1,80 @@
+package gobackend
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+)
+
+const DefaultSpotFetchAPIBaseURL = "https://spotify.afkarxyz.fun/api"
+
+// GetSpotifyDataWithAPI fetches Spotify metadata through SpotFetch-compatible API.
+// This is used as a fallback when direct Spotify API access is blocked/limited.
+func GetSpotifyDataWithAPI(ctx context.Context, spotifyURL, apiBaseURL string) (interface{}, error) {
+	parsed, err := parseSpotifyURI(spotifyURL)
+	if err != nil {
+		return nil, fmt.Errorf("invalid Spotify URL: %w", err)
+	}
+
+	base := strings.TrimSpace(apiBaseURL)
+	if base == "" {
+		base = DefaultSpotFetchAPIBaseURL
+	}
+
+	endpoint := fmt.Sprintf("%s/%s/%s", strings.TrimSuffix(base, "/"), parsed.Type, parsed.ID)
+	req, err := http.NewRequestWithContext(ctx, "GET", endpoint, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create SpotFetch API request: %w", err)
+	}
+	req.Header.Set("User-Agent", getRandomUserAgent())
+	req.Header.Set("Accept", "application/json")
+
+	client := NewHTTPClientWithTimeout(30 * time.Second)
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("SpotFetch API request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("SpotFetch API error: HTTP %d", resp.StatusCode)
+	}
+
+	bodyBytes, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read SpotFetch API response: %w", err)
+	}
+
+	switch parsed.Type {
+	case "track":
+		var trackResp TrackResponse
+		if err := json.Unmarshal(bodyBytes, &trackResp); err != nil {
+			return nil, fmt.Errorf("failed to decode track response: %w", err)
+		}
+		return trackResp, nil
+	case "album":
+		var albumResp AlbumResponsePayload
+		if err := json.Unmarshal(bodyBytes, &albumResp); err != nil {
+			return nil, fmt.Errorf("failed to decode album response: %w", err)
+		}
+		return &albumResp, nil
+	case "playlist":
+		var playlistResp PlaylistResponsePayload
+		if err := json.Unmarshal(bodyBytes, &playlistResp); err != nil {
+			return nil, fmt.Errorf("failed to decode playlist response: %w", err)
+		}
+		return playlistResp, nil
+	case "artist":
+		var artistResp ArtistResponsePayload
+		if err := json.Unmarshal(bodyBytes, &artistResp); err != nil {
+			return nil, fmt.Errorf("failed to decode artist response: %w", err)
+		}
+		return &artistResp, nil
+	default:
+		return nil, fmt.Errorf("unsupported Spotify type: %s", parsed.Type)
+	}
+}

go_backend/spotify.go

@@ -63,10 +63,8 @@ var (
 	credentialsMu      sync.RWMutex
 )
 
-// ErrNoSpotifyCredentials is returned when Spotify credentials are not configured
 var ErrNoSpotifyCredentials = errors.New("Spotify credentials not configured. Please set your own Client ID and Secret in Settings, or use Deezer as metadata source (free, no credentials required)")
 
-// SetSpotifyCredentials sets custom Spotify API credentials
 func SetSpotifyCredentials(clientID, clientSecret string) {
 	credentialsMu.Lock()
 	defer credentialsMu.Unlock()
@@ -89,7 +87,6 @@ func HasSpotifyCredentials() bool {
 	return false
 }
 
-// getCredentials returns the current credentials or error if not configured
 func getCredentials() (string, string, error) {
 	credentialsMu.RLock()
 	defer credentialsMu.RUnlock()
@@ -117,7 +114,7 @@ func NewSpotifyMetadataClient() (*SpotifyMetadataClient, error) {
 	src := rand.NewSource(time.Now().UnixNano())
 
 	c := &SpotifyMetadataClient{
-		httpClient:   NewHTTPClientWithTimeout(15 * time.Second),
+		httpClient:   NewMetadataHTTPClient(15 * time.Second),
 		clientID:     clientID,
 		clientSecret: clientSecret,
 		rng:          rand.New(src),
@@ -143,7 +140,7 @@ type TrackMetadata struct {
 	DiscNumber  int    `json:"disc_number,omitempty"`
 	ExternalURL string `json:"external_urls"`
 	ISRC        string `json:"isrc"`
-	AlbumType   string `json:"album_type,omitempty"` // album, single, ep, compilation
+	AlbumType   string `json:"album_type,omitempty"`
 }
 
 type AlbumTrackMetadata struct {
@@ -212,7 +209,7 @@ type ArtistAlbumMetadata struct {
 	ReleaseDate string `json:"release_date"`
 	TotalTracks int    `json:"total_tracks"`
 	Images      string `json:"images"`
-	AlbumType   string `json:"album_type"` // album, single, compilation
+	AlbumType   string `json:"album_type"`
 	Artists     string `json:"artists"`
 }
 
@@ -534,7 +531,6 @@ func (c *SpotifyMetadataClient) fetchAlbum(ctx context.Context, albumID, token s
 
 	albumImage := firstImageURL(data.Images)
 
-	// Get first artist ID
 	var firstArtistId string
 	if len(data.Artists) > 0 {
 		firstArtistId = data.Artists[0].ID
@@ -567,7 +563,6 @@ func (c *SpotifyMetadataClient) fetchAlbum(ctx context.Context, albumID, token s
 
 	fmt.Printf("[Spotify] Album has %d tracks (total: %d)\n", len(allTrackItems), data.TotalTracks)
 
-	// Collect track IDs for parallel ISRC fetching
 	trackIDs := make([]string, len(allTrackItems))
 	for i, item := range allTrackItems {
 		trackIDs[i] = item.ID
@@ -939,14 +934,14 @@ func (c *SpotifyMetadataClient) randomUserAgent() string {
 	defer c.rngMu.Unlock()
 
 	macMajor := c.rng.Intn(4) + 11
-	macMinor := c.rng.Intn(5) + 4          // 4-8
-	webkitMajor := c.rng.Intn(7) + 530     // 530-536
-	webkitMinor := c.rng.Intn(7) + 30      // 30-36
-	chromeMajor := c.rng.Intn(25) + 80     // 80-104
-	chromeBuild := c.rng.Intn(1500) + 3000 // 3000-4499
-	chromePatch := c.rng.Intn(65) + 60     // 60-124
-	safariMajor := c.rng.Intn(7) + 530     // 530-536
-	safariMinor := c.rng.Intn(6) + 30      // 30-35
+	macMinor := c.rng.Intn(5) + 4
+	webkitMajor := c.rng.Intn(7) + 530
+	webkitMinor := c.rng.Intn(7) + 30
+	chromeMajor := c.rng.Intn(25) + 80
+	chromeBuild := c.rng.Intn(1500) + 3000
+	chromePatch := c.rng.Intn(65) + 60
+	safariMajor := c.rng.Intn(7) + 530
+	safariMinor := c.rng.Intn(6) + 30
 
 	return fmt.Sprintf(
 		"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_%d_%d) AppleWebKit/%d.%d (KHTML, like Gecko) Chrome/%d.0.%d.%d Safari/%d.%d",

go_backend/tidal.go

@@ -119,19 +119,18 @@ func NewTidalDownloader() *TidalDownloader {
 	return globalTidalDownloader
 }
 
-// GetAvailableAPIs returns list of available Tidal APIs
 func (t *TidalDownloader) GetAvailableAPIs() []string {
 	encodedAPIs := []string{
+		"dGlkYWwtYXBpLmJpbmltdW0ub3Jn",     // tidal-api.binimum.org (priority)
 		"dGlkYWwua2lub3BsdXMub25saW5l",     // tidal.kinoplus.online
-		"dGlkYWwtYXBpLmJpbmltdW0ub3Jn",     // tidal-api.binimum.org
 		"dHJpdG9uLnNxdWlkLnd0Zg==",         // triton.squid.wtf
-		"aGlmaS1vbmUuc3BvdGlzYXZlci5uZXQ=", // hifi-one.spotisaver.net
-		"aGlmaS10d28uc3BvdGlzYXZlci5uZXQ=", // hifi-two.spotisaver.net
 		"dm9nZWwucXFkbC5zaXRl",             // vogel.qqdl.site
 		"bWF1cy5xcWRsLnNpdGU=",             // maus.qqdl.site
 		"aHVuZC5xcWRsLnNpdGU=",             // hund.qqdl.site
 		"a2F0emUucXFkbC5zaXRl",             // katze.qqdl.site
 		"d29sZi5xcWRsLnNpdGU=",             // wolf.qqdl.site
+		"aGlmaS1vbmUuc3BvdGlzYXZlci5uZXQ=", // hifi-one.spotisaver.net
+		"aGlmaS10d28uc3BvdGlzYXZlci5uZXQ=", // hifi-two.spotisaver.net
 	}
 
 	var apis []string
@@ -251,7 +250,6 @@ func (t *TidalDownloader) GetTrackIDFromURL(tidalURL string) (int64, error) {
 	return trackID, nil
 }
 
-// GetTrackInfoByID gets track info by Tidal track ID
 func (t *TidalDownloader) GetTrackInfoByID(trackID int64) (*TidalTrack, error) {
 	token, err := t.GetAccessToken()
 	if err != nil {
@@ -319,7 +317,6 @@ func (t *TidalDownloader) SearchTrackByISRC(isrc string) (*TidalTrack, error) {
 		return nil, err
 	}
 
-	// Find exact ISRC match
 	for i := range result.Items {
 		if result.Items[i].ISRC == isrc {
 			return &result.Items[i], nil
@@ -343,7 +340,6 @@ func (t *TidalDownloader) SearchTrackByMetadataWithISRC(trackName, artistName, s
 	// Build search queries - multiple strategies (same as PC version)
 	queries := []string{}
 
-	// Strategy 1: Artist + Track name (original)
 	if artistName != "" && trackName != "" {
 		queries = append(queries, artistName+" "+trackName)
 	}
@@ -586,13 +582,123 @@ type tidalAPIResult struct {
 	duration time.Duration
 }
 
-// Returns the first successful result (supports both v1 and v2 API formats)
+// Tidal API timeout configuration
+// Mobile networks are more unstable, so we use longer timeouts
+const (
+	tidalAPITimeoutMobile = 25 * time.Second
+	tidalMaxRetries       = 2 // Number of retries per API
+	tidalRetryDelay       = 500 * time.Millisecond
+)
+
+// fetchTidalURLWithRetry fetches download URL from a single Tidal API with retry logic
+func fetchTidalURLWithRetry(api string, trackID int64, quality string, timeout time.Duration) (TidalDownloadInfo, error) {
+	var lastErr error
+	retryDelay := tidalRetryDelay
+
+	for attempt := 0; attempt <= tidalMaxRetries; attempt++ {
+		if attempt > 0 {
+			GoLog("[Tidal] Retry %d/%d for %s after %v\n", attempt, tidalMaxRetries, api, retryDelay)
+			time.Sleep(retryDelay)
+			retryDelay *= 2 // Exponential backoff
+		}
+
+		client := NewHTTPClientWithTimeout(timeout)
+		reqURL := fmt.Sprintf("%s/track/?id=%d&quality=%s", api, trackID, quality)
+
+		req, err := http.NewRequest("GET", reqURL, nil)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+
+		resp, err := client.Do(req)
+		if err != nil {
+			lastErr = err
+			// Check for retryable errors (timeout, connection reset)
+			errStr := strings.ToLower(err.Error())
+			if strings.Contains(errStr, "timeout") ||
+				strings.Contains(errStr, "reset") ||
+				strings.Contains(errStr, "connection refused") ||
+				strings.Contains(errStr, "eof") {
+				continue // Retry
+			}
+			break // Non-retryable error
+		}
+		// Server errors are retryable
+		if resp.StatusCode >= 500 {
+			io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			lastErr = fmt.Errorf("HTTP %d", resp.StatusCode)
+			continue
+		}
+
+		// 429 rate limit - wait and retry
+		if resp.StatusCode == 429 {
+			io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			lastErr = fmt.Errorf("rate limited")
+			retryDelay = 2 * time.Second // Wait longer for rate limit
+			continue
+		}
+
+		if resp.StatusCode != 200 {
+			io.Copy(io.Discard, resp.Body)
+			resp.Body.Close()
+			return TidalDownloadInfo{}, fmt.Errorf("HTTP %d", resp.StatusCode)
+		}
+
+		body, err := io.ReadAll(resp.Body)
+		resp.Body.Close()
+		if err != nil {
+			lastErr = err
+			continue
+		}
+
+		// Try V2 response format (with manifest)
+		var v2Response TidalAPIResponseV2
+		if err := json.Unmarshal(body, &v2Response); err == nil && v2Response.Data.Manifest != "" {
+			if v2Response.Data.AssetPresentation == "PREVIEW" {
+				return TidalDownloadInfo{}, fmt.Errorf("returned PREVIEW instead of FULL")
+			}
+
+			return TidalDownloadInfo{
+				URL:        "MANIFEST:" + v2Response.Data.Manifest,
+				BitDepth:   v2Response.Data.BitDepth,
+				SampleRate: v2Response.Data.SampleRate,
+			}, nil
+		}
+
+		// Try V1 response format
+		var v1Responses []struct {
+			OriginalTrackURL string `json:"OriginalTrackUrl"`
+		}
+		if err := json.Unmarshal(body, &v1Responses); err == nil {
+			for _, item := range v1Responses {
+				if item.OriginalTrackURL != "" {
+					return TidalDownloadInfo{
+						URL:        item.OriginalTrackURL,
+						BitDepth:   16,
+						SampleRate: 44100,
+					}, nil
+				}
+			}
+		}
+
+		return TidalDownloadInfo{}, fmt.Errorf("no download URL or manifest in response")
+	}
+
+	if lastErr != nil {
+		return TidalDownloadInfo{}, lastErr
+	}
+	return TidalDownloadInfo{}, fmt.Errorf("all retries failed")
+}
+
 func getDownloadURLParallel(apis []string, trackID int64, quality string) (string, TidalDownloadInfo, error) {
 	if len(apis) == 0 {
 		return "", TidalDownloadInfo{}, fmt.Errorf("no APIs available")
 	}
 
-	GoLog("[Tidal] Requesting download URL from %d APIs in parallel...\n", len(apis))
+	GoLog("[Tidal] Requesting download URL from %d APIs in parallel (with retry)...\n", len(apis))
 
 	resultChan := make(chan tidalAPIResult, len(apis))
 	startTime := time.Now()
@@ -600,69 +706,13 @@ func getDownloadURLParallel(apis []string, trackID int64, quality string) (strin
 	for _, apiURL := range apis {
 		go func(api string) {
 			reqStart := time.Now()
-
-			client := NewHTTPClientWithTimeout(15 * time.Second)
-
-			reqURL := fmt.Sprintf("%s/track/?id=%d&quality=%s", api, trackID, quality)
-
-			req, err := http.NewRequest("GET", reqURL, nil)
-			if err != nil {
-				resultChan <- tidalAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-				return
+			info, err := fetchTidalURLWithRetry(api, trackID, quality, tidalAPITimeoutMobile)
+			resultChan <- tidalAPIResult{
+				apiURL:   api,
+				info:     info,
+				err:      err,
+				duration: time.Since(reqStart),
 			}
-
-			resp, err := client.Do(req)
-			if err != nil {
-				resultChan <- tidalAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-				return
-			}
-			defer resp.Body.Close()
-
-			if resp.StatusCode != 200 {
-				resultChan <- tidalAPIResult{apiURL: api, err: fmt.Errorf("HTTP %d", resp.StatusCode), duration: time.Since(reqStart)}
-				return
-			}
-
-			body, err := io.ReadAll(resp.Body)
-			if err != nil {
-				resultChan <- tidalAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-				return
-			}
-
-			var v2Response TidalAPIResponseV2
-			if err := json.Unmarshal(body, &v2Response); err == nil && v2Response.Data.Manifest != "" {
-				if v2Response.Data.AssetPresentation == "PREVIEW" {
-					resultChan <- tidalAPIResult{apiURL: api, err: fmt.Errorf("returned PREVIEW instead of FULL"), duration: time.Since(reqStart)}
-					return
-				}
-
-				info := TidalDownloadInfo{
-					URL:        "MANIFEST:" + v2Response.Data.Manifest,
-					BitDepth:   v2Response.Data.BitDepth,
-					SampleRate: v2Response.Data.SampleRate,
-				}
-				resultChan <- tidalAPIResult{apiURL: api, info: info, err: nil, duration: time.Since(reqStart)}
-				return
-			}
-
-			var v1Responses []struct {
-				OriginalTrackURL string `json:"OriginalTrackUrl"`
-			}
-			if err := json.Unmarshal(body, &v1Responses); err == nil {
-				for _, item := range v1Responses {
-					if item.OriginalTrackURL != "" {
-						info := TidalDownloadInfo{
-							URL:        item.OriginalTrackURL,
-							BitDepth:   16,
-							SampleRate: 44100,
-						}
-						resultChan <- tidalAPIResult{apiURL: api, info: info, err: nil, duration: time.Since(reqStart)}
-						return
-					}
-				}
-			}
-
-			resultChan <- tidalAPIResult{apiURL: api, err: fmt.Errorf("no download URL or manifest in response"), duration: time.Since(reqStart)}
 		}(apiURL)
 	}
 
@@ -789,6 +839,10 @@ func parseManifest(manifestB64 string) (directURL string, initURL string, mediaU
 		GoLog("[Tidal] Total segments from regex: %d\n", segmentCount)
 	}
 
+	if segmentCount == 0 {
+		return "", "", nil, fmt.Errorf("no segments found in manifest")
+	}
+
 	for i := 1; i <= segmentCount; i++ {
 		mediaURL := strings.ReplaceAll(mediaTemplate, "$Number$", fmt.Sprintf("%d", i))
 		mediaURLs = append(mediaURLs, mediaURL)
@@ -797,8 +851,7 @@ func parseManifest(manifestB64 string) (directURL string, initURL string, mediaU
 	return "", initURL, mediaURLs, nil
 }
 
-// DownloadFile downloads a file from URL with progress tracking
-func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) error {
+func (t *TidalDownloader) DownloadFile(downloadURL, outputPath string, outputFD int, itemID string) error {
 	ctx := context.Background()
 
 	if strings.HasPrefix(downloadURL, "MANIFEST:") {
@@ -811,7 +864,7 @@ func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 		if isDownloadCancelled(itemID) {
 			return ErrDownloadCancelled
 		}
-		return t.downloadFromManifest(ctx, strings.TrimPrefix(downloadURL, "MANIFEST:"), outputPath, itemID)
+		return t.downloadFromManifest(ctx, strings.TrimPrefix(downloadURL, "MANIFEST:"), outputPath, outputFD, itemID)
 	}
 
 	if itemID != "" {
@@ -848,7 +901,7 @@ func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 		SetItemBytesTotal(itemID, expectedSize)
 	}
 
-	out, err := os.Create(outputPath)
+	out, err := openOutputForWrite(outputPath, outputFD)
 	if err != nil {
 		return err
 	}
@@ -867,30 +920,30 @@ func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 	closeErr := out.Close()
 
 	if err != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		if isDownloadCancelled(itemID) {
 			return ErrDownloadCancelled
 		}
 		return fmt.Errorf("download interrupted: %w", err)
 	}
 	if flushErr != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("failed to flush buffer: %w", flushErr)
 	}
 	if closeErr != nil {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("failed to close file: %w", closeErr)
 	}
 
 	if expectedSize > 0 && written != expectedSize {
-		os.Remove(outputPath)
+		cleanupOutputOnError(outputPath, outputFD)
 		return fmt.Errorf("incomplete download: expected %d bytes, got %d bytes", expectedSize, written)
 	}
 
 	return nil
 }
 
-func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64, outputPath, itemID string) error {
+func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64, outputPath string, outputFD int, itemID string) error {
 	fmt.Println("[Tidal] Parsing manifest...")
 	directURL, initURL, mediaURLs, err := parseManifest(manifestB64)
 	if err != nil {
@@ -935,7 +988,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 			SetItemBytesTotal(itemID, expectedSize)
 		}
 
-		out, err := os.Create(outputPath)
+		out, err := openOutputForWrite(outputPath, outputFD)
 		if err != nil {
 			return fmt.Errorf("failed to create file: %w", err)
 		}
@@ -951,29 +1004,40 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 		closeErr := out.Close()
 
 		if err != nil {
-			os.Remove(outputPath)
+			cleanupOutputOnError(outputPath, outputFD)
 			if isDownloadCancelled(itemID) {
 				return ErrDownloadCancelled
 			}
 			return fmt.Errorf("download interrupted: %w", err)
 		}
 		if closeErr != nil {
-			os.Remove(outputPath)
+			cleanupOutputOnError(outputPath, outputFD)
 			return fmt.Errorf("failed to close file: %w", closeErr)
 		}
 
 		if expectedSize > 0 && written != expectedSize {
-			os.Remove(outputPath)
+			cleanupOutputOnError(outputPath, outputFD)
 			return fmt.Errorf("incomplete download: expected %d bytes, got %d bytes", expectedSize, written)
 		}
 
 		return nil
 	}
 
-	m4aPath := strings.TrimSuffix(outputPath, ".flac") + ".m4a"
+	// For DASH format, determine correct M4A path
+	// If outputPath already ends with .m4a, use it directly.
+	// If outputPath ends with .flac, convert .flac to .m4a.
+	// Otherwise (e.g., SAF /proc/self/fd/*), use outputPath as-is.
+	var m4aPath string
+	if strings.HasSuffix(outputPath, ".m4a") {
+		m4aPath = outputPath
+	} else if strings.HasSuffix(outputPath, ".flac") {
+		m4aPath = strings.TrimSuffix(outputPath, ".flac") + ".m4a"
+	} else {
+		m4aPath = outputPath
+	}
 	GoLog("[Tidal] DASH format - downloading %d segments directly to: %s\n", len(mediaURLs), m4aPath)
 
-	out, err := os.Create(m4aPath)
+	out, err := openOutputForWrite(m4aPath, outputFD)
 	if err != nil {
 		GoLog("[Tidal] Failed to create M4A file: %v\n", err)
 		return fmt.Errorf("failed to create M4A file: %w", err)
@@ -982,20 +1046,20 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 	GoLog("[Tidal] Downloading init segment...\n")
 	if isDownloadCancelled(itemID) {
 		out.Close()
-		os.Remove(m4aPath)
+		cleanupOutputOnError(m4aPath, outputFD)
 		return ErrDownloadCancelled
 	}
 	req, err := http.NewRequestWithContext(ctx, "GET", initURL, nil)
 	if err != nil {
 		out.Close()
-		os.Remove(m4aPath)
+		cleanupOutputOnError(m4aPath, outputFD)
 		GoLog("[Tidal] Init segment request failed: %v\n", err)
 		return fmt.Errorf("failed to create init segment request: %w", err)
 	}
 	resp, err := client.Do(req)
 	if err != nil {
 		out.Close()
-		os.Remove(m4aPath)
+		cleanupOutputOnError(m4aPath, outputFD)
 		if isDownloadCancelled(itemID) {
 			return ErrDownloadCancelled
 		}
@@ -1005,7 +1069,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 	if resp.StatusCode != 200 {
 		resp.Body.Close()
 		out.Close()
-		os.Remove(m4aPath)
+		cleanupOutputOnError(m4aPath, outputFD)
 		GoLog("[Tidal] Init segment HTTP error: %d\n", resp.StatusCode)
 		return fmt.Errorf("init segment download failed with status %d", resp.StatusCode)
 	}
@@ -1013,7 +1077,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 	resp.Body.Close()
 	if err != nil {
 		out.Close()
-		os.Remove(m4aPath)
+		cleanupOutputOnError(m4aPath, outputFD)
 		if isDownloadCancelled(itemID) {
 			return ErrDownloadCancelled
 		}
@@ -1025,7 +1089,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 	for i, mediaURL := range mediaURLs {
 		if isDownloadCancelled(itemID) {
 			out.Close()
-			os.Remove(m4aPath)
+			cleanupOutputOnError(m4aPath, outputFD)
 			return ErrDownloadCancelled
 		}
 
@@ -1041,14 +1105,14 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 		req, err := http.NewRequestWithContext(ctx, "GET", mediaURL, nil)
 		if err != nil {
 			out.Close()
-			os.Remove(m4aPath)
+			cleanupOutputOnError(m4aPath, outputFD)
 			GoLog("[Tidal] Segment %d request failed: %v\n", i+1, err)
 			return fmt.Errorf("failed to create segment %d request: %w", i+1, err)
 		}
 		resp, err := client.Do(req)
 		if err != nil {
 			out.Close()
-			os.Remove(m4aPath)
+			cleanupOutputOnError(m4aPath, outputFD)
 			if isDownloadCancelled(itemID) {
 				return ErrDownloadCancelled
 			}
@@ -1058,7 +1122,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 		if resp.StatusCode != 200 {
 			resp.Body.Close()
 			out.Close()
-			os.Remove(m4aPath)
+			cleanupOutputOnError(m4aPath, outputFD)
 			GoLog("[Tidal] Segment %d HTTP error: %d\n", i+1, resp.StatusCode)
 			return fmt.Errorf("segment %d download failed with status %d", i+1, resp.StatusCode)
 		}
@@ -1066,7 +1130,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 		resp.Body.Close()
 		if err != nil {
 			out.Close()
-			os.Remove(m4aPath)
+			cleanupOutputOnError(m4aPath, outputFD)
 			if isDownloadCancelled(itemID) {
 				return ErrDownloadCancelled
 			}
@@ -1076,7 +1140,7 @@ func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64,
 	}
 
 	if err := out.Close(); err != nil {
-		os.Remove(m4aPath)
+		cleanupOutputOnError(m4aPath, outputFD)
 		GoLog("[Tidal] Failed to close M4A file: %v\n", err)
 		return fmt.Errorf("failed to close M4A file: %w", err)
 	}
@@ -1096,6 +1160,7 @@ type TidalDownloadResult struct {
 	TrackNumber int
 	DiscNumber  int
 	ISRC        string
+	LyricsLRC   string // LRC content for embedding in converted files
 }
 
 func artistsMatch(spotifyArtist, tidalArtist string) bool {
@@ -1106,7 +1171,6 @@ func artistsMatch(spotifyArtist, tidalArtist string) bool {
 		return true
 	}
 
-	// Check if one contains the other (for cases like "Artist" vs "Artist feat. Someone")
 	if strings.Contains(normSpotify, normTidal) || strings.Contains(normTidal, normSpotify) {
 		return true
 	}
@@ -1165,7 +1229,6 @@ func sameWordsUnordered(a, b string) bool {
 	wordsA := strings.Fields(a)
 	wordsB := strings.Fields(b)
 
-	// Must have same number of words
 	if len(wordsA) != len(wordsB) || len(wordsA) == 0 {
 		return false
 	}
@@ -1198,7 +1261,6 @@ func titlesMatch(expectedTitle, foundTitle string) bool {
 	normExpected := strings.ToLower(strings.TrimSpace(expectedTitle))
 	normFound := strings.ToLower(strings.TrimSpace(foundTitle))
 
-	// Exact match
 	if normExpected == normFound {
 		return true
 	}
@@ -1207,7 +1269,6 @@ func titlesMatch(expectedTitle, foundTitle string) bool {
 		return true
 	}
 
-	// Clean both titles and compare
 	cleanExpected := cleanTitle(normExpected)
 	cleanFound := cleanTitle(normFound)
 
@@ -1221,7 +1282,6 @@ func titlesMatch(expectedTitle, foundTitle string) bool {
 		}
 	}
 
-	// Extract core title (before any parentheses/brackets)
 	coreExpected := extractCoreTitle(normExpected)
 	coreFound := extractCoreTitle(normFound)
 
@@ -1229,7 +1289,6 @@ func titlesMatch(expectedTitle, foundTitle string) bool {
 		return true
 	}
 
-	// Don't treat Latin Extended (Polish, French, etc.) as different script
 	expectedLatin := isLatinScript(expectedTitle)
 	foundLatin := isLatinScript(foundTitle)
 	if expectedLatin != foundLatin {
@@ -1350,8 +1409,11 @@ func isLatinScript(s string) bool {
 func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 	downloader := NewTidalDownloader()
 
-	if existingFile, exists := checkISRCExistsInternal(req.OutputDir, req.ISRC); exists {
-		return TidalDownloadResult{FilePath: "EXISTS:" + existingFile}, nil
+	isSafOutput := isFDOutput(req.OutputFD) || strings.TrimSpace(req.OutputPath) != ""
+	if !isSafOutput {
+		if existingFile, exists := checkISRCExistsInternal(req.OutputDir, req.ISRC); exists {
+			return TidalDownloadResult{FilePath: "EXISTS:" + existingFile}, nil
+		}
 	}
 
 	expectedDurationSec := req.DurationMS / 1000
@@ -1407,49 +1469,83 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 
 	if track == nil && req.SpotifyID != "" {
 		GoLog("[Tidal] ISRC search failed, trying SongLink...\n")
-		var tidalURL string
-		var slErr error
+
+		var trackID int64
+		var gotTidalID bool
 
 		if strings.HasPrefix(req.SpotifyID, "deezer:") {
 			deezerID := strings.TrimPrefix(req.SpotifyID, "deezer:")
 			GoLog("[Tidal] Using Deezer ID for SongLink lookup: %s\n", deezerID)
 			songlink := NewSongLinkClient()
-			tidalURL, slErr = songlink.GetTidalURLFromDeezer(deezerID)
+			availability, slErr := songlink.CheckAvailabilityFromDeezer(deezerID)
+			if slErr == nil && availability != nil && availability.TidalID != "" {
+				if _, parseErr := fmt.Sscanf(availability.TidalID, "%d", &trackID); parseErr == nil && trackID > 0 {
+					GoLog("[Tidal] Got Tidal ID %d directly from SongLink\n", trackID)
+					gotTidalID = true
+				}
+			}
+			// Fallback to URL parsing if TidalID not in struct
+			if !gotTidalID && availability != nil && availability.TidalURL != "" {
+				var idErr error
+				trackID, idErr = downloader.GetTrackIDFromURL(availability.TidalURL)
+				if idErr == nil && trackID > 0 {
+					GoLog("[Tidal] Got Tidal ID %d from URL parsing\n", trackID)
+					gotTidalID = true
+				}
+			}
 		} else {
-			tidalURL, slErr = downloader.GetTidalURLFromSpotify(req.SpotifyID)
+			songlink := NewSongLinkClient()
+			availability, slErr := songlink.CheckTrackAvailability(req.SpotifyID, req.ISRC)
+			if slErr == nil && availability != nil && availability.TidalID != "" {
+				if _, parseErr := fmt.Sscanf(availability.TidalID, "%d", &trackID); parseErr == nil && trackID > 0 {
+					GoLog("[Tidal] Got Tidal ID %d directly from SongLink\n", trackID)
+					gotTidalID = true
+				}
+			}
+			// Fallback to URL parsing if TidalID not in struct
+			if !gotTidalID && availability != nil && availability.TidalURL != "" {
+				var idErr error
+				trackID, idErr = downloader.GetTrackIDFromURL(availability.TidalURL)
+				if idErr == nil && trackID > 0 {
+					GoLog("[Tidal] Got Tidal ID %d from URL parsing\n", trackID)
+					gotTidalID = true
+				}
+			}
 		}
 
-		if slErr == nil && tidalURL != "" {
-			trackID, idErr := downloader.GetTrackIDFromURL(tidalURL)
-			if idErr == nil {
-				track, err = downloader.GetTrackInfoByID(trackID)
-				if track != nil {
-					tidalArtist := track.Artist.Name
-					if len(track.Artists) > 0 {
-						var artistNames []string
-						for _, a := range track.Artists {
-							artistNames = append(artistNames, a.Name)
-						}
-						tidalArtist = strings.Join(artistNames, ", ")
+		if gotTidalID && trackID > 0 {
+			track, err = downloader.GetTrackInfoByID(trackID)
+			if track != nil {
+				tidalArtist := track.Artist.Name
+				if len(track.Artists) > 0 {
+					var artistNames []string
+					for _, a := range track.Artists {
+						artistNames = append(artistNames, a.Name)
 					}
+					tidalArtist = strings.Join(artistNames, ", ")
+				}
 
-					if !artistsMatch(req.ArtistName, tidalArtist) {
-						GoLog("[Tidal] Artist mismatch from SongLink: expected '%s', got '%s'. Rejecting.\n",
-							req.ArtistName, tidalArtist)
-						track = nil
-					}
+				if !artistsMatch(req.ArtistName, tidalArtist) {
+					GoLog("[Tidal] Artist mismatch from SongLink: expected '%s', got '%s'. Rejecting.\n",
+						req.ArtistName, tidalArtist)
+					track = nil
+				}
 
-					if track != nil && expectedDurationSec > 0 {
-						durationDiff := track.Duration - expectedDurationSec
-						if durationDiff < 0 {
-							durationDiff = -durationDiff
-						}
-						if durationDiff > 3 {
-							GoLog("[Tidal] Duration mismatch from SongLink: expected %ds, got %ds. Rejecting.\n",
-								expectedDurationSec, track.Duration)
-							track = nil // Reject this match
-						}
+				if track != nil && expectedDurationSec > 0 {
+					durationDiff := track.Duration - expectedDurationSec
+					if durationDiff < 0 {
+						durationDiff = -durationDiff
 					}
+					if durationDiff > 3 {
+						GoLog("[Tidal] Duration mismatch from SongLink: expected %ds, got %ds. Rejecting.\n",
+							expectedDurationSec, track.Duration)
+						track = nil // Reject this match
+					}
+				}
+
+				// Cache for future use
+				if track != nil && req.ISRC != "" {
+					GetTrackIDCache().SetTidal(req.ISRC, track.ID)
 				}
 			}
 		}
@@ -1502,35 +1598,69 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		GetTrackIDCache().SetTidal(req.ISRC, track.ID)
 	}
 
+	quality := req.Quality
+	if quality == "" {
+		quality = "LOSSLESS"
+	}
+
 	filename := buildFilenameFromTemplate(req.FilenameFormat, map[string]interface{}{
 		"title":  req.TrackName,
 		"artist": req.ArtistName,
 		"album":  req.AlbumName,
 		"track":  req.TrackNumber,
 		"year":   extractYear(req.ReleaseDate),
+		"date":   req.ReleaseDate,
 		"disc":   req.DiscNumber,
 	})
-	filename = sanitizeFilename(filename) + ".flac"
-	outputPath := filepath.Join(req.OutputDir, filename)
 
-	if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
-		return TidalDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
-	}
-	m4aPath := strings.TrimSuffix(outputPath, ".flac") + ".m4a"
-	if fileInfo, statErr := os.Stat(m4aPath); statErr == nil && fileInfo.Size() > 0 {
-		return TidalDownloadResult{FilePath: "EXISTS:" + m4aPath}, nil
+	outputExt := strings.TrimSpace(req.OutputExt)
+	if outputExt == "" {
+		if quality == "HIGH" {
+			outputExt = ".m4a"
+		} else {
+			outputExt = ".flac"
+		}
+	} else if !strings.HasPrefix(outputExt, ".") {
+		outputExt = "." + outputExt
 	}
 
-	tmpPath := outputPath + ".m4a.tmp"
-	if _, err := os.Stat(tmpPath); err == nil {
-		GoLog("[Tidal] Cleaning up leftover temp file: %s\n", tmpPath)
-		os.Remove(tmpPath)
+	var outputPath string
+	var m4aPath string
+	if isSafOutput {
+		outputPath = strings.TrimSpace(req.OutputPath)
+		if outputPath == "" && isFDOutput(req.OutputFD) {
+			outputPath = fmt.Sprintf("/proc/self/fd/%d", req.OutputFD)
+		}
+		m4aPath = outputPath
+	} else {
+		if outputExt == ".m4a" || quality == "HIGH" {
+			filename = sanitizeFilename(filename) + ".m4a"
+			outputPath = filepath.Join(req.OutputDir, filename)
+			m4aPath = outputPath
+		} else {
+			filename = sanitizeFilename(filename) + ".flac"
+			outputPath = filepath.Join(req.OutputDir, filename)
+			m4aPath = strings.TrimSuffix(outputPath, ".flac") + ".m4a"
+		}
+
+		if fileInfo, statErr := os.Stat(outputPath); statErr == nil && fileInfo.Size() > 0 {
+			return TidalDownloadResult{FilePath: "EXISTS:" + outputPath}, nil
+		}
+		if quality != "HIGH" {
+			if fileInfo, statErr := os.Stat(m4aPath); statErr == nil && fileInfo.Size() > 0 {
+				return TidalDownloadResult{FilePath: "EXISTS:" + m4aPath}, nil
+			}
+		}
 	}
 
-	quality := req.Quality
-	if quality == "" {
-		quality = "LOSSLESS"
+	if !isSafOutput {
+		tmpPath := outputPath + ".m4a.tmp"
+		if _, err := os.Stat(tmpPath); err == nil {
+			GoLog("[Tidal] Cleaning up leftover temp file: %s\n", tmpPath)
+			os.Remove(tmpPath)
+		}
 	}
+
 	GoLog("[Tidal] Using quality: %s\n", quality)
 
 	downloadInfo, err := downloader.GetDownloadURL(track.ID, quality)
@@ -1563,7 +1693,7 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		return "Direct URL"
 	}())
 
-	if err := downloader.DownloadFile(downloadInfo.URL, outputPath, req.ItemID); err != nil {
+	if err := downloader.DownloadFile(downloadInfo.URL, outputPath, req.OutputFD, req.ItemID); err != nil {
 		if errors.Is(err, ErrDownloadCancelled) {
 			return TidalDownloadResult{}, ErrDownloadCancelled
 		}
@@ -1580,11 +1710,13 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 	}
 
 	actualOutputPath := outputPath
-	if _, err := os.Stat(m4aPath); err == nil {
-		actualOutputPath = m4aPath
-		GoLog("[Tidal] File saved as M4A (DASH stream): %s\n", actualOutputPath)
-	} else if _, err := os.Stat(outputPath); err != nil {
-		return TidalDownloadResult{}, fmt.Errorf("download completed but file not found at %s or %s", outputPath, m4aPath)
+	if !isSafOutput {
+		if _, err := os.Stat(m4aPath); err == nil {
+			actualOutputPath = m4aPath
+			GoLog("[Tidal] File saved as M4A (DASH stream): %s\n", actualOutputPath)
+		} else if _, err := os.Stat(outputPath); err != nil {
+			return TidalDownloadResult{}, fmt.Errorf("download completed but file not found at %s or %s", outputPath, m4aPath)
+		}
 	}
 
 	releaseDate := req.ReleaseDate
@@ -1593,7 +1725,6 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		GoLog("[Tidal] Using release date from Tidal API: %s\n", releaseDate)
 	}
 
-	// Use track number from request if available, otherwise from Tidal API
 	actualTrackNumber := req.TrackNumber
 	actualDiscNumber := req.DiscNumber
 	if actualTrackNumber == 0 {
@@ -1624,7 +1755,15 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		GoLog("[Tidal] Using parallel-fetched cover (%d bytes)\n", len(coverData))
 	}
 
-	if strings.HasSuffix(actualOutputPath, ".flac") {
+	actualExt := outputExt
+	if strings.HasPrefix(downloadInfo.URL, "MANIFEST:") {
+		actualExt = ".m4a"
+	}
+	if actualExt == "" && !isSafOutput {
+		actualExt = strings.ToLower(filepath.Ext(actualOutputPath))
+	}
+
+	if (isSafOutput && actualExt == ".flac") || (!isSafOutput && strings.HasSuffix(actualOutputPath, ".flac")) {
 		if err := EmbedMetadataWithCoverData(actualOutputPath, metadata, coverData); err != nil {
 			fmt.Printf("Warning: failed to embed metadata: %v\n", err)
 		}
@@ -1635,7 +1774,7 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 				lyricsMode = "embed"
 			}
 
-			if lyricsMode == "external" || lyricsMode == "both" {
+			if !isSafOutput && (lyricsMode == "external" || lyricsMode == "both") {
 				GoLog("[Tidal] Saving external LRC file...\n")
 				if lrcPath, lrcErr := SaveLRCFile(actualOutputPath, parallelResult.LyricsLRC); lrcErr != nil {
 					GoLog("[Tidal] Warning: failed to save LRC file: %v\n", lrcErr)
@@ -1655,16 +1794,49 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		} else if req.EmbedLyrics {
 			fmt.Println("[Tidal] No lyrics available from parallel fetch")
 		}
-	} else if strings.HasSuffix(actualOutputPath, ".m4a") {
-		fmt.Println("[Tidal] Skipping metadata embedding for M4A file (will be handled after FFmpeg conversion)")
+	} else if (isSafOutput && actualExt == ".m4a") || (!isSafOutput && strings.HasSuffix(actualOutputPath, ".m4a")) {
+		if quality == "HIGH" {
+			GoLog("[Tidal] HIGH quality M4A - skipping metadata embedding (file from server is already valid)\n")
+
+			if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
+				lyricsMode := req.LyricsMode
+				if lyricsMode == "" {
+					lyricsMode = "embed"
+				}
+
+				if !isSafOutput && (lyricsMode == "external" || lyricsMode == "both") {
+					GoLog("[Tidal] Saving external LRC file for M4A (mode: %s)...\n", lyricsMode)
+					if lrcPath, lrcErr := SaveLRCFile(actualOutputPath, parallelResult.LyricsLRC); lrcErr != nil {
+						GoLog("[Tidal] Warning: failed to save LRC file: %v\n", lrcErr)
+					} else {
+						GoLog("[Tidal] LRC file saved: %s\n", lrcPath)
+					}
+				}
+			}
+		} else {
+			fmt.Println("[Tidal] Skipping metadata embedding for M4A file (will be handled after FFmpeg conversion)")
+		}
 	}
 
-	AddToISRCIndex(req.OutputDir, req.ISRC, actualOutputPath)
+	if !isSafOutput {
+		AddToISRCIndex(req.OutputDir, req.ISRC, actualOutputPath)
+	}
+
+	bitDepth := downloadInfo.BitDepth
+	sampleRate := downloadInfo.SampleRate
+	lyricsLRC := ""
+	if quality == "HIGH" {
+		bitDepth = 0
+		sampleRate = 44100
+	}
+	if req.EmbedLyrics && parallelResult != nil && parallelResult.LyricsLRC != "" {
+		lyricsLRC = parallelResult.LyricsLRC
+	}
 
 	return TidalDownloadResult{
 		FilePath:    actualOutputPath,
-		BitDepth:    downloadInfo.BitDepth,
-		SampleRate:  downloadInfo.SampleRate,
+		BitDepth:    bitDepth,
+		SampleRate:  sampleRate,
 		Title:       track.Title,
 		Artist:      track.Artist.Name,
 		Album:       track.Album.Title,
@@ -1672,5 +1844,43 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		TrackNumber: actualTrackNumber,
 		DiscNumber:  actualDiscNumber,
 		ISRC:        track.ISRC,
+		LyricsLRC:   lyricsLRC,
 	}, nil
 }
+
+func parseTidalURL(input string) (string, string, error) {
+	trimmed := strings.TrimSpace(input)
+	if trimmed == "" {
+		return "", "", fmt.Errorf("empty URL")
+	}
+
+	parsed, err := url.Parse(trimmed)
+	if err != nil {
+		return "", "", err
+	}
+
+	if parsed.Host != "tidal.com" && parsed.Host != "listen.tidal.com" && parsed.Host != "www.tidal.com" {
+		return "", "", fmt.Errorf("not a Tidal URL")
+	}
+
+	parts := strings.Split(strings.Trim(parsed.Path, "/"), "/")
+
+	// Handle /browse/track/123 format
+	if len(parts) > 0 && parts[0] == "browse" {
+		parts = parts[1:]
+	}
+
+	if len(parts) < 2 {
+		return "", "", fmt.Errorf("invalid Tidal URL format")
+	}
+
+	resourceType := parts[0]
+	resourceID := parts[1]
+
+	switch resourceType {
+	case "track", "album", "artist", "playlist":
+		return resourceType, resourceID, nil
+	default:
+		return "", "", fmt.Errorf("unsupported Tidal resource type: %s", resourceType)
+	}
+}

go_backend/youtube.go

@@ -0,0 +1,567 @@
+// Package gobackend - YouTube download via Cobalt API (lossy-only provider)
+package gobackend
+
+import (
+	"bufio"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+	"time"
+)
+
+type YouTubeDownloader struct {
+	client *http.Client
+	apiURL string
+	mu     sync.Mutex
+}
+
+var (
+	globalYouTubeDownloader *YouTubeDownloader
+	youtubeDownloaderOnce   sync.Once
+)
+
+type YouTubeQuality string
+
+const (
+	YouTubeQualityOpus256 YouTubeQuality = "opus_256"
+	YouTubeQualityMP3320  YouTubeQuality = "mp3_320"
+)
+
+type CobaltRequest struct {
+	URL             string `json:"url"`
+	AudioBitrate    string `json:"audioBitrate,omitempty"`
+	AudioFormat     string `json:"audioFormat,omitempty"`
+	DownloadMode    string `json:"downloadMode,omitempty"`
+	FilenameStyle   string `json:"filenameStyle,omitempty"`
+	DisableMetadata bool   `json:"disableMetadata,omitempty"`
+}
+
+type CobaltResponse struct {
+	Status   string `json:"status"`
+	URL      string `json:"url,omitempty"`
+	Filename string `json:"filename,omitempty"`
+	Error    *struct {
+		Code    string `json:"code"`
+		Context *struct {
+			Service string `json:"service,omitempty"`
+			Limit   int    `json:"limit,omitempty"`
+		} `json:"context,omitempty"`
+	} `json:"error,omitempty"`
+}
+
+type YouTubeDownloadResult struct {
+	FilePath    string
+	Title       string
+	Artist      string
+	Album       string
+	ReleaseDate string
+	TrackNumber int
+	DiscNumber  int
+	ISRC        string
+	Format      string // "opus" or "mp3"
+	Bitrate     int
+	LyricsLRC   string
+	CoverData   []byte
+}
+
+func NewYouTubeDownloader() *YouTubeDownloader {
+	youtubeDownloaderOnce.Do(func() {
+		globalYouTubeDownloader = &YouTubeDownloader{
+			client: NewHTTPClientWithTimeout(120 * time.Second),
+			apiURL: "https://api.qwkuns.me",
+		}
+	})
+	return globalYouTubeDownloader
+}
+
+// SearchYouTube returns a YouTube Music search URL for the given track
+func (y *YouTubeDownloader) SearchYouTube(trackName, artistName string) (string, error) {
+	query := fmt.Sprintf("%s %s", artistName, trackName)
+	searchQuery := url.QueryEscape(query)
+
+	GoLog("[YouTube] Search query: %s\n", query)
+
+	youtubeMusicURL := fmt.Sprintf("https://music.youtube.com/search?q=%s", searchQuery)
+
+	return youtubeMusicURL, nil
+}
+
+func (y *YouTubeDownloader) GetDownloadURL(youtubeURL string, quality YouTubeQuality) (*CobaltResponse, error) {
+	y.mu.Lock()
+	defer y.mu.Unlock()
+
+	var audioFormat string
+	var audioBitrate string
+
+	switch quality {
+	case YouTubeQualityOpus256:
+		audioFormat = "opus"
+		audioBitrate = "256"
+	case YouTubeQualityMP3320:
+		audioFormat = "mp3"
+		audioBitrate = "320"
+	default:
+		audioFormat = "mp3"
+		audioBitrate = "320"
+	}
+
+	// Try SpotubeDL first (primary)
+	videoID, extractErr := ExtractYouTubeVideoID(youtubeURL)
+	if extractErr == nil {
+		GoLog("[YouTube] Requesting from SpotubeDL: videoID=%s (format: %s, bitrate: %s)\n",
+			videoID, audioFormat, audioBitrate)
+
+		resp, err := y.requestSpotubeDL(videoID, audioFormat, audioBitrate)
+		if err == nil {
+			return resp, nil
+		}
+		GoLog("[YouTube] SpotubeDL failed: %v, trying Cobalt fallback...\n", err)
+	} else {
+		GoLog("[YouTube] Could not extract video ID: %v, skipping SpotubeDL\n", extractErr)
+	}
+
+	// Fallback: direct Cobalt API (api.qwkuns.me)
+	cobaltURL := toYouTubeMusicURL(youtubeURL)
+	GoLog("[YouTube] Requesting from Cobalt API: %s (format: %s, bitrate: %s)\n",
+		cobaltURL, audioFormat, audioBitrate)
+
+	resp, err := y.requestCobaltDirect(cobaltURL, audioFormat, audioBitrate)
+	if err != nil {
+		return nil, fmt.Errorf("all download methods failed: spotubedl: extractErr=%v, cobalt: %v", extractErr, err)
+	}
+
+	return resp, nil
+}
+
+// requestCobaltDirect sends a download request to the primary Cobalt API.
+func (y *YouTubeDownloader) requestCobaltDirect(videoURL, audioFormat, audioBitrate string) (*CobaltResponse, error) {
+	reqBody := CobaltRequest{
+		URL:             videoURL,
+		AudioFormat:     audioFormat,
+		AudioBitrate:    audioBitrate,
+		DownloadMode:    "audio",
+		FilenameStyle:   "basic",
+		DisableMetadata: true,
+	}
+
+	jsonData, err := json.Marshal(reqBody)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal request: %w", err)
+	}
+
+	req, err := http.NewRequest("POST", y.apiURL, strings.NewReader(string(jsonData)))
+	if err != nil {
+		return nil, fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Accept", "application/json")
+
+	resp, err := DoRequestWithUserAgent(y.client, req)
+	if err != nil {
+		return nil, fmt.Errorf("cobalt API request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response: %w", err)
+	}
+
+	GoLog("[YouTube] Cobalt API response status: %d\n", resp.StatusCode)
+
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("cobalt API returned status %d: %s", resp.StatusCode, string(body))
+	}
+
+	var cobaltResp CobaltResponse
+	if err := json.Unmarshal(body, &cobaltResp); err != nil {
+		return nil, fmt.Errorf("failed to parse response: %w", err)
+	}
+
+	if cobaltResp.Status == "error" && cobaltResp.Error != nil {
+		return nil, fmt.Errorf("cobalt error: %s", cobaltResp.Error.Code)
+	}
+
+	if cobaltResp.Status != "tunnel" && cobaltResp.Status != "redirect" {
+		return nil, fmt.Errorf("unexpected cobalt status: %s", cobaltResp.Status)
+	}
+
+	if cobaltResp.URL == "" {
+		return nil, fmt.Errorf("no download URL in response")
+	}
+
+	GoLog("[YouTube] Got download URL from Cobalt (status: %s)\n", cobaltResp.Status)
+	return &cobaltResp, nil
+}
+
+// requestSpotubeDL uses SpotubeDL as a Cobalt proxy (they handle auth to yt-dl.click instances).
+func (y *YouTubeDownloader) requestSpotubeDL(videoID, audioFormat, audioBitrate string) (*CobaltResponse, error) {
+	apiURL := fmt.Sprintf("https://spotubedl.com/api/download/%s?engine=v1&format=%s&quality=%s",
+		videoID, audioFormat, audioBitrate)
+
+	GoLog("[YouTube] Requesting from SpotubeDL: %s\n", apiURL)
+
+	req, err := http.NewRequest("GET", apiURL, nil)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create request: %w", err)
+	}
+
+	req.Header.Set("Accept", "application/json")
+
+	resp, err := DoRequestWithUserAgent(y.client, req)
+	if err != nil {
+		return nil, fmt.Errorf("spotubedl request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read response: %w", err)
+	}
+
+	GoLog("[YouTube] SpotubeDL response status: %d\n", resp.StatusCode)
+
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("spotubedl returned status %d: %s", resp.StatusCode, string(body))
+	}
+
+	var result struct {
+		URL string `json:"url"`
+	}
+	if err := json.Unmarshal(body, &result); err != nil {
+		return nil, fmt.Errorf("failed to parse spotubedl response: %w", err)
+	}
+
+	if result.URL == "" {
+		return nil, fmt.Errorf("no download URL from spotubedl")
+	}
+
+	GoLog("[YouTube] Got download URL from SpotubeDL\n")
+	return &CobaltResponse{
+		Status: "tunnel",
+		URL:    result.URL,
+	}, nil
+}
+
+func (y *YouTubeDownloader) DownloadFile(downloadURL, outputPath string, outputFD int, itemID string) error {
+	ctx := context.Background()
+
+	if itemID != "" {
+		StartItemProgress(itemID)
+		defer CompleteItemProgress(itemID)
+		ctx = initDownloadCancel(itemID)
+		defer clearDownloadCancel(itemID)
+	}
+
+	if isDownloadCancelled(itemID) {
+		return ErrDownloadCancelled
+	}
+
+	req, err := http.NewRequestWithContext(ctx, "GET", downloadURL, nil)
+	if err != nil {
+		return fmt.Errorf("failed to create request: %w", err)
+	}
+
+	resp, err := DoRequestWithUserAgent(y.client, req)
+	if err != nil {
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
+		return fmt.Errorf("download request failed: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return fmt.Errorf("download failed: HTTP %d", resp.StatusCode)
+	}
+
+	expectedSize := resp.ContentLength
+	if expectedSize > 0 && itemID != "" {
+		SetItemBytesTotal(itemID, expectedSize)
+	}
+
+	out, err := openOutputForWrite(outputPath, outputFD)
+	if err != nil {
+		return fmt.Errorf("failed to create output file: %w", err)
+	}
+
+	bufWriter := bufio.NewWriterSize(out, 256*1024)
+
+	var written int64
+	if itemID != "" {
+		progressWriter := NewItemProgressWriter(bufWriter, itemID)
+		written, err = io.Copy(progressWriter, resp.Body)
+	} else {
+		written, err = io.Copy(bufWriter, resp.Body)
+	}
+
+	flushErr := bufWriter.Flush()
+	closeErr := out.Close()
+
+	if err != nil {
+		cleanupOutputOnError(outputPath, outputFD)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
+		return fmt.Errorf("download interrupted: %w", err)
+	}
+	if flushErr != nil {
+		cleanupOutputOnError(outputPath, outputFD)
+		return fmt.Errorf("failed to flush buffer: %w", flushErr)
+	}
+	if closeErr != nil {
+		cleanupOutputOnError(outputPath, outputFD)
+		return fmt.Errorf("failed to close file: %w", closeErr)
+	}
+
+	if expectedSize > 0 && written != expectedSize {
+		cleanupOutputOnError(outputPath, outputFD)
+		return fmt.Errorf("incomplete download: expected %d bytes, got %d bytes", expectedSize, written)
+	}
+
+	GoLog("[YouTube] Download completed: %d bytes written\n", written)
+
+	return nil
+}
+
+func BuildYouTubeSearchURL(trackName, artistName string) string {
+	query := fmt.Sprintf("%s %s official audio", artistName, trackName)
+	return fmt.Sprintf("https://music.youtube.com/search?q=%s", url.QueryEscape(query))
+}
+
+func BuildYouTubeWatchURL(videoID string) string {
+	return fmt.Sprintf("https://music.youtube.com/watch?v=%s", videoID)
+}
+
+// isYouTubeVideoID checks if s is an 11-char YouTube video ID
+func isYouTubeVideoID(s string) bool {
+	if len(s) != 11 {
+		return false
+	}
+	for _, c := range s {
+		if !((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '-' || c == '_') {
+			return false
+		}
+	}
+	return true
+}
+
+func IsYouTubeURL(urlStr string) bool {
+	lower := strings.ToLower(urlStr)
+	return strings.Contains(lower, "youtube.com") ||
+		strings.Contains(lower, "youtu.be") ||
+		strings.Contains(lower, "music.youtube.com")
+}
+
+// toYouTubeMusicURL converts any YouTube URL to music.youtube.com format.
+// YouTube Music URLs bypass the login requirement that affects regular YouTube videos on Cobalt.
+func toYouTubeMusicURL(rawURL string) string {
+	videoID, err := ExtractYouTubeVideoID(rawURL)
+	if err != nil {
+		return rawURL
+	}
+	return fmt.Sprintf("https://music.youtube.com/watch?v=%s", videoID)
+}
+
+func ExtractYouTubeVideoID(urlStr string) (string, error) {
+	if strings.Contains(urlStr, "youtu.be/") {
+		parts := strings.Split(urlStr, "youtu.be/")
+		if len(parts) >= 2 {
+			videoID := strings.Split(parts[1], "?")[0]
+			videoID = strings.Split(videoID, "&")[0]
+			return strings.TrimSpace(videoID), nil
+		}
+	}
+
+	parsed, err := url.Parse(urlStr)
+	if err != nil {
+		return "", fmt.Errorf("invalid URL: %w", err)
+	}
+
+	// /watch?v=
+	if v := parsed.Query().Get("v"); v != "" {
+		return v, nil
+	}
+
+	// /embed/
+	if strings.Contains(parsed.Path, "/embed/") {
+		parts := strings.Split(parsed.Path, "/embed/")
+		if len(parts) >= 2 {
+			return strings.Split(parts[1], "/")[0], nil
+		}
+	}
+
+	// /v/
+	if strings.Contains(parsed.Path, "/v/") {
+		parts := strings.Split(parsed.Path, "/v/")
+		if len(parts) >= 2 {
+			return strings.Split(parts[1], "/")[0], nil
+		}
+	}
+
+	return "", fmt.Errorf("could not extract video ID from URL")
+}
+
+func downloadFromYouTube(req DownloadRequest) (YouTubeDownloadResult, error) {
+	downloader := NewYouTubeDownloader()
+
+	var quality YouTubeQuality
+	switch strings.ToLower(req.Quality) {
+	case "opus_256", "opus256", "opus":
+		quality = YouTubeQualityOpus256
+	case "mp3_320", "mp3320", "mp3":
+		quality = YouTubeQualityMP3320
+	default:
+		quality = YouTubeQualityMP3320 // Default to MP3 320kbps
+	}
+
+	// URL lookup priority: YouTube video ID > Spotify ID > Deezer ID > ISRC
+	var youtubeURL string
+	var lookupErr error
+
+	// SpotifyID might actually be a YouTube video ID (from YT Music extension)
+	if req.SpotifyID != "" && isYouTubeVideoID(req.SpotifyID) {
+		youtubeURL = BuildYouTubeWatchURL(req.SpotifyID)
+		GoLog("[YouTube] SpotifyID appears to be YouTube video ID, using directly: %s\n", youtubeURL)
+	}
+
+	// Try Spotify ID via SongLink
+	if youtubeURL == "" && req.SpotifyID != "" && !isYouTubeVideoID(req.SpotifyID) {
+		GoLog("[YouTube] Looking up YouTube URL via SongLink for Spotify ID: %s\n", req.SpotifyID)
+		songlink := NewSongLinkClient()
+		youtubeURL, lookupErr = songlink.GetYouTubeURLFromSpotify(req.SpotifyID)
+		if lookupErr != nil {
+			GoLog("[YouTube] SongLink Spotify lookup failed: %v\n", lookupErr)
+		} else {
+			GoLog("[YouTube] Found YouTube URL via SongLink (Spotify): %s\n", youtubeURL)
+		}
+	}
+
+	// Try Deezer ID via SongLink
+	if youtubeURL == "" && req.DeezerID != "" {
+		GoLog("[YouTube] Looking up YouTube URL via SongLink for Deezer ID: %s\n", req.DeezerID)
+		songlink := NewSongLinkClient()
+		youtubeURL, lookupErr = songlink.GetYouTubeURLFromDeezer(req.DeezerID)
+		if lookupErr != nil {
+			GoLog("[YouTube] SongLink Deezer lookup failed: %v\n", lookupErr)
+		} else {
+			GoLog("[YouTube] Found YouTube URL via SongLink (Deezer): %s\n", youtubeURL)
+		}
+	}
+
+	// Try ISRC via SongLink
+	if youtubeURL == "" && req.ISRC != "" {
+		GoLog("[YouTube] Looking up YouTube URL via SongLink for ISRC: %s\n", req.ISRC)
+		songlink := NewSongLinkClient()
+		availability, isrcErr := songlink.CheckTrackAvailability("", req.ISRC)
+		if isrcErr == nil && availability.YouTube && availability.YouTubeURL != "" {
+			youtubeURL = availability.YouTubeURL
+			GoLog("[YouTube] Found YouTube URL via SongLink (ISRC): %s\n", youtubeURL)
+		} else if isrcErr != nil {
+			GoLog("[YouTube] SongLink ISRC lookup failed: %v\n", isrcErr)
+		}
+	}
+
+	// Cobalt requires direct video URLs, not search URLs
+	if youtubeURL == "" {
+		return YouTubeDownloadResult{}, fmt.Errorf("could not find YouTube URL for track: %s - %s (no Spotify/Deezer ID available or track not on YouTube)", req.ArtistName, req.TrackName)
+	}
+
+	GoLog("[YouTube] Requesting download from Cobalt for: %s\n", youtubeURL)
+
+	cobaltResp, err := downloader.GetDownloadURL(youtubeURL, quality)
+	if err != nil {
+		return YouTubeDownloadResult{}, fmt.Errorf("failed to get download URL: %w", err)
+	}
+
+	var ext string
+	var format string
+	var bitrate int
+	switch quality {
+	case YouTubeQualityOpus256:
+		ext = ".opus"
+		format = "opus"
+		bitrate = 256
+	case YouTubeQualityMP3320:
+		ext = ".mp3"
+		format = "mp3"
+		bitrate = 320
+	}
+
+	filename := buildFilenameFromTemplate(req.FilenameFormat, map[string]any{
+		"title":  req.TrackName,
+		"artist": req.ArtistName,
+		"album":  req.AlbumName,
+		"track":  req.TrackNumber,
+		"year":   extractYear(req.ReleaseDate),
+		"date":   req.ReleaseDate,
+		"disc":   req.DiscNumber,
+	})
+	filename = sanitizeFilename(filename) + ext
+
+	var outputPath string
+	isSafOutput := isFDOutput(req.OutputFD) || strings.TrimSpace(req.OutputPath) != ""
+	if isSafOutput {
+		outputPath = strings.TrimSpace(req.OutputPath)
+		if outputPath == "" && isFDOutput(req.OutputFD) {
+			outputPath = fmt.Sprintf("/proc/self/fd/%d", req.OutputFD)
+		}
+	} else {
+		outputPath = req.OutputDir + "/" + filename
+	}
+
+	GoLog("[YouTube] Downloading to: %s\n", outputPath)
+
+	// Parallel fetch cover art + lyrics
+	var parallelResult *ParallelDownloadResult
+	if req.EmbedLyrics || req.CoverURL != "" {
+		GoLog("[YouTube] Starting parallel fetch for cover and lyrics...\n")
+		parallelResult = FetchCoverAndLyricsParallel(
+			req.CoverURL,
+			req.EmbedMaxQualityCover,
+			req.SpotifyID,
+			req.TrackName,
+			req.ArtistName,
+			req.EmbedLyrics,
+			int64(req.DurationMS),
+		)
+	}
+
+	if err := downloader.DownloadFile(cobaltResp.URL, outputPath, req.OutputFD, req.ItemID); err != nil {
+		return YouTubeDownloadResult{}, fmt.Errorf("download failed: %w", err)
+	}
+
+	lyricsLRC := ""
+	var coverData []byte
+	if parallelResult != nil {
+		if parallelResult.LyricsLRC != "" {
+			lyricsLRC = parallelResult.LyricsLRC
+			GoLog("[YouTube] Got lyrics from lrclib (%d lines)\n", len(parallelResult.LyricsData.Lines))
+		}
+		if parallelResult.CoverData != nil {
+			coverData = parallelResult.CoverData
+			GoLog("[YouTube] Got cover art (%d bytes)\n", len(coverData))
+		}
+	}
+
+	return YouTubeDownloadResult{
+		FilePath:    outputPath,
+		Title:       req.TrackName,
+		Artist:      req.ArtistName,
+		Album:       req.AlbumName,
+		ReleaseDate: req.ReleaseDate,
+		TrackNumber: req.TrackNumber,
+		DiscNumber:  req.DiscNumber,
+		ISRC:        req.ISRC,
+		Format:      format,
+		Bitrate:     bitrate,
+		LyricsLRC:   lyricsLRC,
+		CoverData:   coverData,
+	}, nil
+}

ios/Podfile

@@ -46,6 +46,11 @@ post_install do |installer|
     flutter_additional_ios_build_settings(target)
     target.build_configurations.each do |config|
       config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '14.0'
+      config.build_settings['GCC_PREPROCESSOR_DEFINITIONS'] ||= ['$(inherited)']
+      definitions = config.build_settings['GCC_PREPROCESSOR_DEFINITIONS']
+      unless definitions.include?('PERMISSION_NOTIFICATIONS=1')
+        definitions << 'PERMISSION_NOTIFICATIONS=1'
+      end
     end
   end
 end

ios/Runner/AppDelegate.swift

@@ -83,18 +83,12 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
             
-        case "downloadTrack":
+        case "downloadByStrategy":
             let requestJson = call.arguments as! String
-            let response = GobackendDownloadTrack(requestJson, &error)
+            let response = GobackendDownloadByStrategy(requestJson, &error)
             if let error = error { throw error }
             return response
-            
-        case "downloadWithFallback":
-            let requestJson = call.arguments as! String
-            let response = GobackendDownloadWithFallback(requestJson, &error)
-            if let error = error { throw error }
-            return response
-            
+
         case "getDownloadProgress":
             let response = GobackendGetDownloadProgress()
             return response
@@ -209,6 +203,41 @@ import Gobackend  // Import Go framework
         case "cleanupConnections":
             GobackendCleanupConnections()
             return nil
+
+        case "downloadCoverToFile":
+            let args = call.arguments as! [String: Any]
+            let coverURL = args["cover_url"] as! String
+            let outputPath = args["output_path"] as! String
+            let maxQuality = args["max_quality"] as? Bool ?? true
+            GobackendDownloadCoverToFile(coverURL, outputPath, maxQuality, &error)
+            if let error = error { throw error }
+            return "{\"success\":true}"
+
+        case "extractCoverToFile":
+            let args = call.arguments as! [String: Any]
+            let audioPath = args["audio_path"] as! String
+            let outputPath = args["output_path"] as! String
+            GobackendExtractCoverToFile(audioPath, outputPath, &error)
+            if let error = error { throw error }
+            return "{\"success\":true}"
+
+        case "fetchAndSaveLyrics":
+            let args = call.arguments as! [String: Any]
+            let trackName = args["track_name"] as! String
+            let artistName = args["artist_name"] as! String
+            let spotifyId = args["spotify_id"] as! String
+            let durationMs = args["duration_ms"] as? Int64 ?? 0
+            let outputPath = args["output_path"] as! String
+            GobackendFetchAndSaveLyrics(trackName, artistName, spotifyId, durationMs, outputPath, &error)
+            if let error = error { throw error }
+            return "{\"success\":true}"
+
+        case "reEnrichFile":
+            let args = call.arguments as! [String: Any]
+            let requestJson = args["request_json"] as? String ?? "{}"
+            let response = GobackendReEnrichFile(requestJson, &error)
+            if let error = error { throw error }
+            return response
             
         case "readFileMetadata":
             let args = call.arguments as! [String: Any]
@@ -217,6 +246,14 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
             
+        case "editFileMetadata":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let metadataJson = args["metadata_json"] as? String ?? "{}"
+            let response = GobackendEditFileMetadata(filePath, metadataJson, &error)
+            if let error = error { throw error }
+            return response
+            
         case "searchDeezerAll":
             let args = call.arguments as! [String: Any]
             let query = args["query"] as! String
@@ -242,6 +279,20 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
 
+        case "parseTidalUrl":
+            let args = call.arguments as! [String: Any]
+            let url = args["url"] as! String
+            let response = GobackendParseTidalURLExport(url, &error)
+            if let error = error { throw error }
+            return response
+
+        case "convertTidalToSpotifyDeezer":
+            let args = call.arguments as! [String: Any]
+            let url = args["url"] as! String
+            let response = GobackendConvertTidalToSpotifyDeezer(url, &error)
+            if let error = error { throw error }
+            return response
+
         case "searchDeezerByISRC":
             let args = call.arguments as! [String: Any]
             let isrc = args["isrc"] as! String
@@ -457,12 +508,6 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
             
-        case "downloadWithExtensions":
-            let requestJson = call.arguments as! String
-            let response = GobackendDownloadWithExtensionsJSON(requestJson, &error)
-            if let error = error { throw error }
-            return response
-            
         case "enrichTrackWithExtension":
             let args = call.arguments as! [String: Any]
             let extensionId = args["extension_id"] as! String
@@ -470,6 +515,12 @@ import Gobackend  // Import Go framework
             let response = GobackendEnrichTrackWithExtensionJSON(extensionId, trackJson, &error)
             if let error = error { throw error }
             return response
+
+        case "downloadWithExtensions":
+            let requestJson = call.arguments as! String
+            let response = GobackendDownloadWithExtensionsJSON(requestJson, &error)
+            if let error = error { throw error }
+            return response
             
         case "removeExtension":
             let args = call.arguments as! [String: Any]
@@ -625,6 +676,14 @@ import Gobackend  // Import Go framework
             let response = GobackendRunPostProcessingJSON(filePath, metadataJson, &error)
             if let error = error { throw error }
             return response
+
+        case "runPostProcessingV2":
+            let args = call.arguments as! [String: Any]
+            let inputJson = args["input"] as? String ?? ""
+            let metadataJson = args["metadata"] as? String ?? ""
+            let response = GobackendRunPostProcessingV2JSON(inputJson, metadataJson, &error)
+            if let error = error { throw error }
+            return response
             
         case "getPostProcessingProviders":
             let response = GobackendGetPostProcessingProvidersJSON(&error)
@@ -687,6 +746,43 @@ import Gobackend  // Import Go framework
             if let error = error { throw error }
             return response
             
+        // Local Library Scanning
+        case "setLibraryCoverCacheDir":
+            let args = call.arguments as! [String: Any]
+            let cacheDir = args["cache_dir"] as! String
+            GobackendSetLibraryCoverCacheDirJSON(cacheDir)
+            return nil
+            
+        case "scanLibraryFolder":
+            let args = call.arguments as! [String: Any]
+            let folderPath = args["folder_path"] as! String
+            let response = GobackendScanLibraryFolderJSON(folderPath, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "scanLibraryFolderIncremental":
+            let args = call.arguments as! [String: Any]
+            let folderPath = args["folder_path"] as! String
+            let existingFiles = args["existing_files"] as? String ?? "{}"
+            let response = GobackendScanLibraryFolderIncrementalJSON(folderPath, existingFiles, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "getLibraryScanProgress":
+            let response = GobackendGetLibraryScanProgressJSON()
+            return response
+            
+        case "cancelLibraryScan":
+            GobackendCancelLibraryScanJSON()
+            return nil
+            
+        case "readAudioMetadata":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let response = GobackendReadAudioMetadataJSON(filePath, &error)
+            if let error = error { throw error }
+            return response
+            
         default:
             throw NSError(
                 domain: "SpotiFLAC",

ios/Runner/Info.plist

@@ -67,7 +67,7 @@
 	<key>NSAppTransportSecurity</key>
 	<dict>
 		<key>NSAllowsArbitraryLoads</key>
-		<true/>
+		<false/>
 	</dict>
 	
 	<!-- File Sharing - Allow access via Files app -->
@@ -81,5 +81,29 @@
 	<!-- Photo Library (for cover art if needed) -->
 	<key>NSPhotoLibraryUsageDescription</key>
 	<string>SpotiFLAC needs access to save album artwork</string>
+	
+	<!-- URL Schemes for deep linking -->
+	<key>CFBundleURLTypes</key>
+	<array>
+		<dict>
+			<key>CFBundleTypeRole</key>
+			<string>Viewer</string>
+			<key>CFBundleURLName</key>
+			<string>com.zarz.spotiflac</string>
+			<key>CFBundleURLSchemes</key>
+			<array>
+				<string>spotiflac</string>
+			</array>
+		</dict>
+	</array>
+	
+	<!-- Associated Domains for Universal Links -->
+	<key>LSApplicationQueriesSchemes</key>
+	<array>
+		<string>spotify</string>
+		<string>deezer</string>
+		<string>tidal</string>
+		<string>youtube-music</string>
+	</array>
 </dict>
 </plist>

lib/app.dart

@@ -4,36 +4,55 @@ import 'package:flutter_localizations/flutter_localizations.dart';
 import 'package:go_router/go_router.dart';
 import 'package:spotiflac_android/screens/main_shell.dart';
 import 'package:spotiflac_android/screens/setup_screen.dart';
+import 'package:spotiflac_android/screens/tutorial_screen.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
 import 'package:spotiflac_android/theme/dynamic_color_wrapper.dart';
 import 'package:spotiflac_android/l10n/app_localizations.dart';
 
 final _routerProvider = Provider<GoRouter>((ref) {
-  final isFirstLaunch = ref.watch(settingsProvider.select((s) => s.isFirstLaunch));
-  
+  final isFirstLaunch = ref.watch(
+    settingsProvider.select((s) => s.isFirstLaunch),
+  );
+  final hasCompletedTutorial = ref.watch(
+    settingsProvider.select((s) => s.hasCompletedTutorial),
+  );
+
+  // Determine initial location based on app state
+  String initialLocation;
+  if (isFirstLaunch) {
+    initialLocation = '/setup';
+  } else if (!hasCompletedTutorial) {
+    initialLocation = '/tutorial';
+  } else {
+    initialLocation = '/';
+  }
+
   return GoRouter(
-    initialLocation: isFirstLaunch ? '/setup' : '/',
+    initialLocation: initialLocation,
     routes: [
+      GoRoute(path: '/', builder: (context, state) => const MainShell()),
+      GoRoute(path: '/setup', builder: (context, state) => const SetupScreen()),
       GoRoute(
-        path: '/',
-        builder: (context, state) => const MainShell(),
-      ),
-      GoRoute(
-        path: '/setup',
-        builder: (context, state) => const SetupScreen(),
+        path: '/tutorial',
+        builder: (context, state) => const TutorialScreen(),
       ),
     ],
   );
 });
 
 class SpotiFLACApp extends ConsumerWidget {
-  const SpotiFLACApp({super.key});
+  final bool disableOverscrollEffects;
+
+  const SpotiFLACApp({super.key, this.disableOverscrollEffects = false});
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     final router = ref.watch(_routerProvider);
     final localeString = ref.watch(settingsProvider.select((s) => s.locale));
-    
+    final scrollBehavior = disableOverscrollEffects
+        ? const MaterialScrollBehavior().copyWith(overscroll: false)
+        : null;
+
     Locale? locale;
     if (localeString != 'system') {
       if (localeString.contains('_')) {
@@ -43,7 +62,7 @@ class SpotiFLACApp extends ConsumerWidget {
         locale = Locale(localeString);
       }
     }
-    
+
     return DynamicColorWrapper(
       builder: (lightTheme, darkTheme, themeMode) {
         return MaterialApp.router(
@@ -52,6 +71,7 @@ class SpotiFLACApp extends ConsumerWidget {
           theme: lightTheme,
           darkTheme: darkTheme,
           themeMode: themeMode,
+          scrollBehavior: scrollBehavior,
           themeAnimationDuration: const Duration(milliseconds: 300),
           themeAnimationCurve: Curves.easeInOut,
           routerConfig: router,

lib/constants/app_info.dart

@@ -1,8 +1,8 @@
 /// App version and info constants
 /// Update version here only - all other files will reference this
 class AppInfo {
-static const String version = '3.3.0';
-  static const String buildNumber = '67';
+  static const String version = '3.6.7';
+  static const String buildNumber = '81';
   static const String fullVersion = '$version+$buildNumber';
   
   
@@ -17,4 +17,5 @@ static const String version = '3.3.0';
   static const String originalGithubUrl = 'https://github.com/afkarxyz/SpotiFLAC';
   
   static const String kofiUrl = 'https://ko-fi.com/zarzet';
+  static const String githubSponsorsUrl = 'https://github.com/sponsors/zarzet/';
 }

lib/l10n/app_localizations_en.dart

@@ -18,6 +18,9 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get navHome => 'Home';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => 'History';
 
@@ -340,6 +343,10 @@ class AppLocalizationsEn extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify requires your own API credentials. Get them free from developer.spotify.com';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => 'Extensions';
 
@@ -450,12 +457,6 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get aboutSupport => 'Support';
 
-  @override
-  String get aboutBuyMeCoffee => 'Buy me a coffee';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Support development on Ko-fi';
-
   @override
   String get aboutApp => 'App';
 
@@ -488,6 +489,13 @@ class AppLocalizationsEn extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'The best Qobuz streaming API. Hi-Res downloads wouldn\'t be possible without this!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Download Spotify tracks in lossless quality from Tidal, Qobuz, and Amazon Music.';
@@ -684,6 +692,10 @@ class AppLocalizationsEn extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Download Spotify tracks in FLAC';
 
@@ -939,6 +951,11 @@ class AppLocalizationsEn extends AppLocalizations {
     return '\"$trackName\" already downloaded';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => 'History cleared';
 
@@ -1165,6 +1182,13 @@ class AppLocalizationsEn extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Show advanced tags';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Enable formatted tags for track padding and date patterns';
+
   @override
   String get folderOrganization => 'Folder Organization';
 
@@ -1895,6 +1919,10 @@ class AppLocalizationsEn extends AppLocalizations {
   String get qualityNote =>
       'Actual quality depends on track availability from the service';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'Ask Before Download';
 
@@ -1907,6 +1935,28 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'Album Folder Structure';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => 'Save Format';
 
@@ -1986,6 +2036,39 @@ class AppLocalizationsEn extends AppLocalizations {
   String get queueClearAllMessage =>
       'Are you sure you want to clear all downloads?';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'No downloads in queue';
 
@@ -2109,6 +2192,12 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'Playlist';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'Playlist: $name';
@@ -2208,4 +2297,649 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/app_localizations_hi.dart

@@ -18,6 +18,9 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get navHome => 'होम';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => 'इतिहास';
 
@@ -340,6 +343,10 @@ class AppLocalizationsHi extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify requires your own API credentials. Get them free from developer.spotify.com';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => 'Extensions';
 
@@ -450,12 +457,6 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get aboutSupport => 'Support';
 
-  @override
-  String get aboutBuyMeCoffee => 'Buy me a coffee';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Support development on Ko-fi';
-
   @override
   String get aboutApp => 'App';
 
@@ -488,6 +489,13 @@ class AppLocalizationsHi extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'The best Qobuz streaming API. Hi-Res downloads wouldn\'t be possible without this!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Download Spotify tracks in lossless quality from Tidal, Qobuz, and Amazon Music.';
@@ -684,6 +692,10 @@ class AppLocalizationsHi extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Download Spotify tracks in FLAC';
 
@@ -939,6 +951,11 @@ class AppLocalizationsHi extends AppLocalizations {
     return '\"$trackName\" already downloaded';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => 'History cleared';
 
@@ -1165,6 +1182,13 @@ class AppLocalizationsHi extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Show advanced tags';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Enable formatted tags for track padding and date patterns';
+
   @override
   String get folderOrganization => 'Folder Organization';
 
@@ -1895,6 +1919,10 @@ class AppLocalizationsHi extends AppLocalizations {
   String get qualityNote =>
       'Actual quality depends on track availability from the service';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'Ask Before Download';
 
@@ -1907,6 +1935,28 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'Album Folder Structure';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => 'Save Format';
 
@@ -1986,6 +2036,39 @@ class AppLocalizationsHi extends AppLocalizations {
   String get queueClearAllMessage =>
       'Are you sure you want to clear all downloads?';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'No downloads in queue';
 
@@ -2109,6 +2192,12 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'Playlist';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'Playlist: $name';
@@ -2208,4 +2297,649 @@ class AppLocalizationsHi extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/app_localizations_id.dart

@@ -18,6 +18,9 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get navHome => 'Beranda';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => 'Riwayat';
 
@@ -344,6 +347,10 @@ class AppLocalizationsId extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify memerlukan kredensial API Anda sendiri. Dapatkan gratis dari developer.spotify.com';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => 'Ekstensi';
 
@@ -455,12 +462,6 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get aboutSupport => 'Dukungan';
 
-  @override
-  String get aboutBuyMeCoffee => 'Belikan saya kopi';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Dukung pengembangan di Ko-fi';
-
   @override
   String get aboutApp => 'Aplikasi';
 
@@ -493,6 +494,13 @@ class AppLocalizationsId extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'API streaming Qobuz terbaik. Unduhan Hi-Res tidak akan mungkin tanpa ini!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Unduh lagu Spotify dalam kualitas lossless dari Tidal, Qobuz, dan Amazon Music.';
@@ -689,6 +697,10 @@ class AppLocalizationsId extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'Batasan iOS: Folder kosong tidak dapat dipilih. Pilih folder dengan minimal satu file.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Unduh lagu Spotify dalam format FLAC';
 
@@ -945,6 +957,11 @@ class AppLocalizationsId extends AppLocalizations {
     return '\"$trackName\" sudah diunduh';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => 'Riwayat dihapus';
 
@@ -1171,6 +1188,13 @@ class AppLocalizationsId extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Tampilkan tag lanjutan';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Aktifkan tag format untuk padding nomor lagu dan pola tanggal';
+
   @override
   String get folderOrganization => 'Organisasi Folder';
 
@@ -1907,6 +1931,10 @@ class AppLocalizationsId extends AppLocalizations {
   String get qualityNote =>
       'Kualitas sebenarnya tergantung ketersediaan lagu dari layanan';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'Tanya Sebelum Unduh';
 
@@ -1919,6 +1947,28 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'Struktur Folder Album';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => 'Simpan Format';
 
@@ -1999,6 +2049,39 @@ class AppLocalizationsId extends AppLocalizations {
   String get queueClearAllMessage =>
       'Apakah Anda yakin ingin menghapus semua unduhan?';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'Tidak ada unduhan dalam antrian';
 
@@ -2122,6 +2205,12 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'Playlist';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'Playlist: $name';
@@ -2133,70 +2222,70 @@ class AppLocalizationsId extends AppLocalizations {
   }
 
   @override
-  String get discographyDownload => 'Unduh Diskografi';
+  String get discographyDownload => 'Download Discography';
 
   @override
   String get discographyDownloadAll => 'Unduh Semua';
 
   @override
   String discographyDownloadAllSubtitle(int count, int albumCount) {
-    return '$count lagu dari $albumCount rilis';
+    return '$count tracks from $albumCount releases';
   }
 
   @override
-  String get discographyAlbumsOnly => 'Album Saja';
+  String get discographyAlbumsOnly => 'Albums Only';
 
   @override
   String discographyAlbumsOnlySubtitle(int count, int albumCount) {
-    return '$count lagu dari $albumCount album';
+    return '$count tracks from $albumCount albums';
   }
 
   @override
-  String get discographySinglesOnly => 'Single & EP Saja';
+  String get discographySinglesOnly => 'Singles & EPs Only';
 
   @override
   String discographySinglesOnlySubtitle(int count, int albumCount) {
-    return '$count lagu dari $albumCount single';
+    return '$count tracks from $albumCount singles';
   }
 
   @override
-  String get discographySelectAlbums => 'Pilih Album...';
+  String get discographySelectAlbums => 'Select Albums...';
 
   @override
   String get discographySelectAlbumsSubtitle =>
-      'Pilih album atau single tertentu';
+      'Choose specific albums or singles';
 
   @override
-  String get discographyFetchingTracks => 'Mengambil lagu...';
+  String get discographyFetchingTracks => 'Fetching tracks...';
 
   @override
   String discographyFetchingAlbum(int current, int total) {
-    return 'Mengambil $current dari $total...';
+    return 'Fetching $current of $total...';
   }
 
   @override
   String discographySelectedCount(int count) {
-    return '$count dipilih';
+    return '$count selected';
   }
 
   @override
-  String get discographyDownloadSelected => 'Unduh yang Dipilih';
+  String get discographyDownloadSelected => 'Download Selected';
 
   @override
   String discographyAddedToQueue(int count) {
-    return 'Menambahkan $count lagu ke antrian';
+    return 'Added $count tracks to queue';
   }
 
   @override
   String discographySkippedDownloaded(int added, int skipped) {
-    return '$added ditambahkan, $skipped sudah diunduh';
+    return '$added added, $skipped already downloaded';
   }
 
   @override
-  String get discographyNoAlbums => 'Tidak ada album tersedia';
+  String get discographyNoAlbums => 'No albums available';
 
   @override
-  String get discographyFailedToFetch => 'Gagal mengambil beberapa album';
+  String get discographyFailedToFetch => 'Failed to fetch some albums';
 
   @override
   String get sectionStorageAccess => 'Storage Access';
@@ -2221,4 +2310,649 @@ class AppLocalizationsId extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/app_localizations_ja.dart

@@ -18,6 +18,9 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get navHome => 'ホーム';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => '履歴';
 
@@ -337,6 +340,10 @@ class AppLocalizationsJa extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify は独自の API 認証情報が必要です。developer.spotify.com から取得できます。';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => '拡張';
 
@@ -446,12 +453,6 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get aboutSupport => 'サポート';
 
-  @override
-  String get aboutBuyMeCoffee => 'コーヒーを買ってください';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Ko-fi で開発をサポートします';
-
   @override
   String get aboutApp => 'アプリ';
 
@@ -484,6 +485,13 @@ class AppLocalizationsJa extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'The best Qobuz streaming API. Hi-Res downloads wouldn\'t be possible without this!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Tidal、Qobuz、Amazon Music から Spotify のトラックをロスレス品質でダウンロードします。';
@@ -679,6 +687,10 @@ class AppLocalizationsJa extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Spotify のトラックを FLAC でダウンロード';
 
@@ -934,6 +946,11 @@ class AppLocalizationsJa extends AppLocalizations {
     return '「$trackName」は既にダウンロードされています';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => '履歴を消去しました';
 
@@ -1159,6 +1176,13 @@ class AppLocalizationsJa extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Show advanced tags';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Enable formatted tags for track padding and date patterns';
+
   @override
   String get folderOrganization => 'フォルダ構成';
 
@@ -1883,6 +1907,10 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get qualityNote => '実際の品質はサービスからのトラックの可用性に依存します';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'ダウンロード前に確認する';
 
@@ -1895,6 +1923,28 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'アルバムフォルダの構造';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => '形式を保存';
 
@@ -1973,6 +2023,39 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get queueClearAllMessage => 'すべてのダウンロードを消去してもよろしいですか？';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'キューにダウンロードがありません';
 
@@ -2095,6 +2178,12 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'プレイリスト';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'プレイリスト: $name';
@@ -2194,4 +2283,649 @@ class AppLocalizationsJa extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/app_localizations_ko.dart

@@ -13,11 +13,14 @@ class AppLocalizationsKo extends AppLocalizations {
 
   @override
   String get appDescription =>
-      'Download Spotify tracks in lossless quality from Tidal, Qobuz, and Amazon Music.';
+      'Spotify 트랙을 Tidal, Qobuz, Amazon Music에서 무손실 음질로 다운로드하세요.';
 
   @override
   String get navHome => 'Home';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => 'History';
 
@@ -31,32 +34,32 @@ class AppLocalizationsKo extends AppLocalizations {
   String get homeTitle => 'Home';
 
   @override
-  String get homeSearchHint => 'Paste Spotify URL or search...';
+  String get homeSearchHint => 'Spotify URL을 붙여 넣거나 검색';
 
   @override
   String homeSearchHintExtension(String extensionName) {
-    return 'Search with $extensionName...';
+    return '$extensionName에서 검색';
   }
 
   @override
-  String get homeSubtitle => 'Paste a Spotify link or search by name';
+  String get homeSubtitle => 'Spotify URL을 붙여 넣거나 검색';
 
   @override
-  String get homeSupports => 'Supports: Track, Album, Playlist, Artist URLs';
+  String get homeSupports => '지원 항목: 트랙, 앨범, 플레이리스트, 아티스트 URLs';
 
   @override
-  String get homeRecent => 'Recent';
+  String get homeRecent => '최근 기록';
 
   @override
-  String get historyTitle => 'History';
+  String get historyTitle => '기록';
 
   @override
   String historyDownloading(int count) {
-    return 'Downloading ($count)';
+    return '다운로드 중... $count';
   }
 
   @override
-  String get historyDownloaded => 'Downloaded';
+  String get historyDownloaded => '다운로드 목록';
 
   @override
   String get historyFilterAll => 'All';
@@ -72,7 +75,7 @@ class AppLocalizationsKo extends AppLocalizations {
     String _temp0 = intl.Intl.pluralLogic(
       count,
       locale: localeName,
-      other: '$count tracks',
+      other: '${count}tracks',
       one: '1 track',
     );
     return '$_temp0';
@@ -242,14 +245,13 @@ class AppLocalizationsKo extends AppLocalizations {
   String get optionsAutoFallback => 'Auto Fallback';
 
   @override
-  String get optionsAutoFallbackSubtitle =>
-      'Try other services if download fails';
+  String get optionsAutoFallbackSubtitle => '다운로드가 실패한 경우, 다른 서비스로 재시도';
 
   @override
   String get optionsUseExtensionProviders => 'Use Extension Providers';
 
   @override
-  String get optionsUseExtensionProvidersOn => 'Extensions will be tried first';
+  String get optionsUseExtensionProvidersOn => '확장 기능을 우선적으로 사용합니다';
 
   @override
   String get optionsUseExtensionProvidersOff => 'Using built-in providers only';
@@ -340,6 +342,10 @@ class AppLocalizationsKo extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify requires your own API credentials. Get them free from developer.spotify.com';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => 'Extensions';
 
@@ -450,12 +456,6 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get aboutSupport => 'Support';
 
-  @override
-  String get aboutBuyMeCoffee => 'Buy me a coffee';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Support development on Ko-fi';
-
   @override
   String get aboutApp => 'App';
 
@@ -488,6 +488,13 @@ class AppLocalizationsKo extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'The best Qobuz streaming API. Hi-Res downloads wouldn\'t be possible without this!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Download Spotify tracks in lossless quality from Tidal, Qobuz, and Amazon Music.';
@@ -684,6 +691,10 @@ class AppLocalizationsKo extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Download Spotify tracks in FLAC';
 
@@ -939,6 +950,11 @@ class AppLocalizationsKo extends AppLocalizations {
     return '\"$trackName\" already downloaded';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => 'History cleared';
 
@@ -1165,6 +1181,13 @@ class AppLocalizationsKo extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Show advanced tags';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Enable formatted tags for track padding and date patterns';
+
   @override
   String get folderOrganization => 'Folder Organization';
 
@@ -1895,6 +1918,10 @@ class AppLocalizationsKo extends AppLocalizations {
   String get qualityNote =>
       'Actual quality depends on track availability from the service';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'Ask Before Download';
 
@@ -1907,6 +1934,28 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'Album Folder Structure';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => 'Save Format';
 
@@ -1986,6 +2035,39 @@ class AppLocalizationsKo extends AppLocalizations {
   String get queueClearAllMessage =>
       'Are you sure you want to clear all downloads?';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'No downloads in queue';
 
@@ -2109,6 +2191,12 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'Playlist';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'Playlist: $name';
@@ -2208,4 +2296,649 @@ class AppLocalizationsKo extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/app_localizations_nl.dart

@@ -18,6 +18,9 @@ class AppLocalizationsNl extends AppLocalizations {
   @override
   String get navHome => 'Home';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => 'History';
 
@@ -340,6 +343,10 @@ class AppLocalizationsNl extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify requires your own API credentials. Get them free from developer.spotify.com';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => 'Extensions';
 
@@ -450,12 +457,6 @@ class AppLocalizationsNl extends AppLocalizations {
   @override
   String get aboutSupport => 'Support';
 
-  @override
-  String get aboutBuyMeCoffee => 'Buy me a coffee';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Support development on Ko-fi';
-
   @override
   String get aboutApp => 'App';
 
@@ -488,6 +489,13 @@ class AppLocalizationsNl extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'The best Qobuz streaming API. Hi-Res downloads wouldn\'t be possible without this!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Download Spotify tracks in lossless quality from Tidal, Qobuz, and Amazon Music.';
@@ -684,6 +692,10 @@ class AppLocalizationsNl extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Download Spotify tracks in FLAC';
 
@@ -939,6 +951,11 @@ class AppLocalizationsNl extends AppLocalizations {
     return '\"$trackName\" already downloaded';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => 'History cleared';
 
@@ -1165,6 +1182,13 @@ class AppLocalizationsNl extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Show advanced tags';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Enable formatted tags for track padding and date patterns';
+
   @override
   String get folderOrganization => 'Folder Organization';
 
@@ -1895,6 +1919,10 @@ class AppLocalizationsNl extends AppLocalizations {
   String get qualityNote =>
       'Actual quality depends on track availability from the service';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'Ask Before Download';
 
@@ -1907,6 +1935,28 @@ class AppLocalizationsNl extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'Album Folder Structure';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => 'Save Format';
 
@@ -1986,6 +2036,39 @@ class AppLocalizationsNl extends AppLocalizations {
   String get queueClearAllMessage =>
       'Are you sure you want to clear all downloads?';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'No downloads in queue';
 
@@ -2109,6 +2192,12 @@ class AppLocalizationsNl extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'Playlist';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'Playlist: $name';
@@ -2208,4 +2297,649 @@ class AppLocalizationsNl extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/app_localizations_tr.dart

@@ -18,6 +18,9 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get navHome => 'Ara';
 
+  @override
+  String get navLibrary => 'Library';
+
   @override
   String get navHistory => 'Geçmiş';
 
@@ -345,6 +348,10 @@ class AppLocalizationsTr extends AppLocalizations {
   String get optionsSpotifyWarning =>
       'Spotify\'ın senin API kimlik bilgilerine ihtiyacı var. Onları developer.spotify.com\'dan alabilirsin';
 
+  @override
+  String get optionsSpotifyDeprecationWarning =>
+      'Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.';
+
   @override
   String get extensionsTitle => 'Eklentiler';
 
@@ -457,12 +464,6 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get aboutSupport => 'Destek';
 
-  @override
-  String get aboutBuyMeCoffee => 'Bana bir kahve ısmarla';
-
-  @override
-  String get aboutBuyMeCoffeeSubtitle => 'Ko-fi üzerinden uygulamayı destekle';
-
   @override
   String get aboutApp => 'Uygulama';
 
@@ -495,6 +496,13 @@ class AppLocalizationsTr extends AppLocalizations {
   String get aboutDabMusicDesc =>
       'En iyi Qobuz streaming API\'ı. Yüksek kalite indirmeler bunun sayesinde!';
 
+  @override
+  String get aboutSpotiSaver => 'SpotiSaver';
+
+  @override
+  String get aboutSpotiSaverDesc =>
+      'Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!';
+
   @override
   String get aboutAppDescription =>
       'Spotify şarkılarını Tidal, Qobuz ve Amazon Music\'den yüksek kalitede indir.';
@@ -691,6 +699,10 @@ class AppLocalizationsTr extends AppLocalizations {
   String get setupIosEmptyFolderWarning =>
       'iOS\'un sınırlaması: Boş klasörler seçilemiyor. İçinde en az bir dosya bulunan bir klasör seçin.';
 
+  @override
+  String get setupIcloudNotSupported =>
+      'iCloud Drive is not supported. Please use the app Documents folder.';
+
   @override
   String get setupDownloadInFlac => 'Spotify şarkılarını FLAC olarak indirin';
 
@@ -946,6 +958,11 @@ class AppLocalizationsTr extends AppLocalizations {
     return '\"$trackName\" zaten indirilmiş';
   }
 
+  @override
+  String snackbarAlreadyInLibrary(String trackName) {
+    return '\"$trackName\" already exists in your library';
+  }
+
   @override
   String get snackbarHistoryCleared => 'Geçmiş temizlendi';
 
@@ -1172,6 +1189,13 @@ class AppLocalizationsTr extends AppLocalizations {
     return '$artist - $title';
   }
 
+  @override
+  String get filenameShowAdvancedTags => 'Show advanced tags';
+
+  @override
+  String get filenameShowAdvancedTagsDescription =>
+      'Enable formatted tags for track padding and date patterns';
+
   @override
   String get folderOrganization => 'Klasör Organizasyonu';
 
@@ -1910,6 +1934,10 @@ class AppLocalizationsTr extends AppLocalizations {
   String get qualityNote =>
       'Actual quality depends on track availability from the service';
 
+  @override
+  String get youtubeQualityNote =>
+      'YouTube provides lossy audio only. Not part of lossless fallback.';
+
   @override
   String get downloadAskBeforeDownload => 'Ask Before Download';
 
@@ -1922,6 +1950,28 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get downloadAlbumFolderStructure => 'Album Folder Structure';
 
+  @override
+  String get downloadUseAlbumArtistForFolders => 'Use Album Artist for folders';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersAlbumSubtitle =>
+      'Artist folders use Album Artist when available';
+
+  @override
+  String get downloadUseAlbumArtistForFoldersTrackSubtitle =>
+      'Artist folders use Track Artist only';
+
+  @override
+  String get downloadUsePrimaryArtistOnly => 'Primary artist only for folders';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyEnabled =>
+      'Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)';
+
+  @override
+  String get downloadUsePrimaryArtistOnlyDisabled =>
+      'Full artist string used for folder name';
+
   @override
   String get downloadSaveFormat => 'Save Format';
 
@@ -2001,6 +2051,39 @@ class AppLocalizationsTr extends AppLocalizations {
   String get queueClearAllMessage =>
       'Are you sure you want to clear all downloads?';
 
+  @override
+  String get queueExportFailed => 'Export';
+
+  @override
+  String get queueExportFailedSuccess =>
+      'Failed downloads exported to TXT file';
+
+  @override
+  String get queueExportFailedClear => 'Clear Failed';
+
+  @override
+  String get queueExportFailedError => 'Failed to export downloads';
+
+  @override
+  String get settingsAutoExportFailed => 'Auto-export failed downloads';
+
+  @override
+  String get settingsAutoExportFailedSubtitle =>
+      'Save failed downloads to TXT file automatically';
+
+  @override
+  String get settingsDownloadNetwork => 'Download Network';
+
+  @override
+  String get settingsDownloadNetworkAny => 'WiFi + Mobile Data';
+
+  @override
+  String get settingsDownloadNetworkWifiOnly => 'WiFi Only';
+
+  @override
+  String get settingsDownloadNetworkSubtitle =>
+      'Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.';
+
   @override
   String get queueEmpty => 'No downloads in queue';
 
@@ -2124,6 +2207,12 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get recentTypePlaylist => 'Playlist';
 
+  @override
+  String get recentEmpty => 'No recent items yet';
+
+  @override
+  String get recentShowAllDownloads => 'Show All Downloads';
+
   @override
   String recentPlaylistInfo(String name) {
     return 'Playlist: $name';
@@ -2223,4 +2312,649 @@ class AppLocalizationsTr extends AppLocalizations {
   @override
   String get allFilesAccessDisabledMessage =>
       'All Files Access disabled. The app will use limited storage access.';
+
+  @override
+  String get settingsLocalLibrary => 'Local Library';
+
+  @override
+  String get settingsLocalLibrarySubtitle => 'Scan music & detect duplicates';
+
+  @override
+  String get settingsCache => 'Storage & Cache';
+
+  @override
+  String get settingsCacheSubtitle => 'View size and clear cached data';
+
+  @override
+  String get libraryTitle => 'Local Library';
+
+  @override
+  String get libraryStatus => 'Library Status';
+
+  @override
+  String get libraryScanSettings => 'Scan Settings';
+
+  @override
+  String get libraryEnableLocalLibrary => 'Enable Local Library';
+
+  @override
+  String get libraryEnableLocalLibrarySubtitle =>
+      'Scan and track your existing music';
+
+  @override
+  String get libraryFolder => 'Library Folder';
+
+  @override
+  String get libraryFolderHint => 'Tap to select folder';
+
+  @override
+  String get libraryShowDuplicateIndicator => 'Show Duplicate Indicator';
+
+  @override
+  String get libraryShowDuplicateIndicatorSubtitle =>
+      'Show when searching for existing tracks';
+
+  @override
+  String get libraryActions => 'Actions';
+
+  @override
+  String get libraryScan => 'Scan Library';
+
+  @override
+  String get libraryScanSubtitle => 'Scan for audio files';
+
+  @override
+  String get libraryScanSelectFolderFirst => 'Select a folder first';
+
+  @override
+  String get libraryCleanupMissingFiles => 'Cleanup Missing Files';
+
+  @override
+  String get libraryCleanupMissingFilesSubtitle =>
+      'Remove entries for files that no longer exist';
+
+  @override
+  String get libraryClear => 'Clear Library';
+
+  @override
+  String get libraryClearSubtitle => 'Remove all scanned tracks';
+
+  @override
+  String get libraryClearConfirmTitle => 'Clear Library';
+
+  @override
+  String get libraryClearConfirmMessage =>
+      'This will remove all scanned tracks from your library. Your actual music files will not be deleted.';
+
+  @override
+  String get libraryAbout => 'About Local Library';
+
+  @override
+  String get libraryAboutDescription =>
+      'Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.';
+
+  @override
+  String libraryTracksCount(int count) {
+    return '$count tracks';
+  }
+
+  @override
+  String libraryLastScanned(String time) {
+    return 'Last scanned: $time';
+  }
+
+  @override
+  String get libraryLastScannedNever => 'Never';
+
+  @override
+  String get libraryScanning => 'Scanning...';
+
+  @override
+  String libraryScanProgress(String progress, int total) {
+    return '$progress% of $total files';
+  }
+
+  @override
+  String get libraryInLibrary => 'In Library';
+
+  @override
+  String libraryRemovedMissingFiles(int count) {
+    return 'Removed $count missing files from library';
+  }
+
+  @override
+  String get libraryCleared => 'Library cleared';
+
+  @override
+  String get libraryStorageAccessRequired => 'Storage Access Required';
+
+  @override
+  String get libraryStorageAccessMessage =>
+      'SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.';
+
+  @override
+  String get libraryFolderNotExist => 'Selected folder does not exist';
+
+  @override
+  String get librarySourceDownloaded => 'Downloaded';
+
+  @override
+  String get librarySourceLocal => 'Local';
+
+  @override
+  String get libraryFilterAll => 'All';
+
+  @override
+  String get libraryFilterDownloaded => 'Downloaded';
+
+  @override
+  String get libraryFilterLocal => 'Local';
+
+  @override
+  String get libraryFilterTitle => 'Filters';
+
+  @override
+  String get libraryFilterReset => 'Reset';
+
+  @override
+  String get libraryFilterApply => 'Apply';
+
+  @override
+  String get libraryFilterSource => 'Source';
+
+  @override
+  String get libraryFilterQuality => 'Quality';
+
+  @override
+  String get libraryFilterQualityHiRes => 'Hi-Res (24bit)';
+
+  @override
+  String get libraryFilterQualityCD => 'CD (16bit)';
+
+  @override
+  String get libraryFilterQualityLossy => 'Lossy';
+
+  @override
+  String get libraryFilterFormat => 'Format';
+
+  @override
+  String get libraryFilterDate => 'Date Added';
+
+  @override
+  String get libraryFilterDateToday => 'Today';
+
+  @override
+  String get libraryFilterDateWeek => 'This Week';
+
+  @override
+  String get libraryFilterDateMonth => 'This Month';
+
+  @override
+  String get libraryFilterDateYear => 'This Year';
+
+  @override
+  String get libraryFilterSort => 'Sort';
+
+  @override
+  String get libraryFilterSortLatest => 'Latest';
+
+  @override
+  String get libraryFilterSortOldest => 'Oldest';
+
+  @override
+  String libraryFilterActive(int count) {
+    return '$count filter(s) active';
+  }
+
+  @override
+  String get timeJustNow => 'Just now';
+
+  @override
+  String timeMinutesAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count minutes ago',
+      one: '1 minute ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String timeHoursAgo(int count) {
+    String _temp0 = intl.Intl.pluralLogic(
+      count,
+      locale: localeName,
+      other: '$count hours ago',
+      one: '1 hour ago',
+    );
+    return '$_temp0';
+  }
+
+  @override
+  String get storageSwitchTitle => 'Switch Storage Mode';
+
+  @override
+  String get storageSwitchToSafTitle => 'Switch to SAF Storage?';
+
+  @override
+  String get storageSwitchToAppTitle => 'Switch to App Storage?';
+
+  @override
+  String get storageSwitchToSafMessage =>
+      'Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.';
+
+  @override
+  String get storageSwitchToAppMessage =>
+      'Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.';
+
+  @override
+  String get storageSwitchExistingDownloads => 'Existing Downloads';
+
+  @override
+  String storageSwitchExistingDownloadsInfo(int count, String mode) {
+    return '$count tracks in $mode storage';
+  }
+
+  @override
+  String get storageSwitchNewDownloads => 'New Downloads';
+
+  @override
+  String storageSwitchNewDownloadsLocation(String location) {
+    return 'Will be saved to: $location';
+  }
+
+  @override
+  String get storageSwitchContinue => 'Continue';
+
+  @override
+  String get storageSwitchSelectFolder => 'Select SAF Folder';
+
+  @override
+  String get storageAppStorage => 'App Storage';
+
+  @override
+  String get storageSafStorage => 'SAF Storage';
+
+  @override
+  String storageModeBadge(String mode) {
+    return 'Storage: $mode';
+  }
+
+  @override
+  String get storageStatsTitle => 'Storage Statistics';
+
+  @override
+  String storageStatsAppCount(int count) {
+    return '$count tracks in App Storage';
+  }
+
+  @override
+  String storageStatsSafCount(int count) {
+    return '$count tracks in SAF Storage';
+  }
+
+  @override
+  String get storageModeInfo => 'Your files are stored in multiple locations';
+
+  @override
+  String get tutorialWelcomeTitle => 'Welcome to SpotiFLAC!';
+
+  @override
+  String get tutorialWelcomeDesc =>
+      'Let\'s learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.';
+
+  @override
+  String get tutorialWelcomeTip1 =>
+      'Download music from Spotify, Deezer, or paste any supported URL';
+
+  @override
+  String get tutorialWelcomeTip2 =>
+      'Get FLAC quality audio from Tidal, Qobuz, or Amazon Music';
+
+  @override
+  String get tutorialWelcomeTip3 =>
+      'Automatic metadata, cover art, and lyrics embedding';
+
+  @override
+  String get tutorialSearchTitle => 'Finding Music';
+
+  @override
+  String get tutorialSearchDesc =>
+      'There are two easy ways to find music you want to download.';
+
+  @override
+  String get tutorialSearchTip1 =>
+      'Paste a Spotify or Deezer URL directly in the search box';
+
+  @override
+  String get tutorialSearchTip2 =>
+      'Or type the song name, artist, or album to search';
+
+  @override
+  String get tutorialSearchTip3 =>
+      'Supports tracks, albums, playlists, and artist pages';
+
+  @override
+  String get tutorialDownloadTitle => 'Downloading Music';
+
+  @override
+  String get tutorialDownloadDesc =>
+      'Downloading music is simple and fast. Here\'s how it works.';
+
+  @override
+  String get tutorialDownloadTip1 =>
+      'Tap the download button next to any track to start downloading';
+
+  @override
+  String get tutorialDownloadTip2 =>
+      'Choose your preferred quality (FLAC, Hi-Res, or MP3)';
+
+  @override
+  String get tutorialDownloadTip3 =>
+      'Download entire albums or playlists with one tap';
+
+  @override
+  String get tutorialLibraryTitle => 'Your Library';
+
+  @override
+  String get tutorialLibraryDesc =>
+      'All your downloaded music is organized in the Library tab.';
+
+  @override
+  String get tutorialLibraryTip1 =>
+      'View download progress and queue in the Library tab';
+
+  @override
+  String get tutorialLibraryTip2 =>
+      'Tap any track to play it with your music player';
+
+  @override
+  String get tutorialLibraryTip3 =>
+      'Switch between list and grid view for better browsing';
+
+  @override
+  String get tutorialExtensionsTitle => 'Extensions';
+
+  @override
+  String get tutorialExtensionsDesc =>
+      'Extend the app\'s capabilities with community extensions.';
+
+  @override
+  String get tutorialExtensionsTip1 =>
+      'Browse the Store tab to discover useful extensions';
+
+  @override
+  String get tutorialExtensionsTip2 =>
+      'Add new download providers or search sources';
+
+  @override
+  String get tutorialExtensionsTip3 =>
+      'Get lyrics, enhanced metadata, and more features';
+
+  @override
+  String get tutorialSettingsTitle => 'Customize Your Experience';
+
+  @override
+  String get tutorialSettingsDesc =>
+      'Personalize the app in Settings to match your preferences.';
+
+  @override
+  String get tutorialSettingsTip1 =>
+      'Change download location and folder organization';
+
+  @override
+  String get tutorialSettingsTip2 =>
+      'Set default audio quality and format preferences';
+
+  @override
+  String get tutorialSettingsTip3 => 'Customize app theme and appearance';
+
+  @override
+  String get tutorialReadyMessage =>
+      'You\'re all set! Start downloading your favorite music now.';
+
+  @override
+  String get tutorialExample => 'EXAMPLE';
+
+  @override
+  String get libraryForceFullScan => 'Force Full Scan';
+
+  @override
+  String get libraryForceFullScanSubtitle => 'Rescan all files, ignoring cache';
+
+  @override
+  String get cleanupOrphanedDownloads => 'Cleanup Orphaned Downloads';
+
+  @override
+  String get cleanupOrphanedDownloadsSubtitle =>
+      'Remove history entries for files that no longer exist';
+
+  @override
+  String cleanupOrphanedDownloadsResult(int count) {
+    return 'Removed $count orphaned entries from history';
+  }
+
+  @override
+  String get cleanupOrphanedDownloadsNone => 'No orphaned entries found';
+
+  @override
+  String get cacheTitle => 'Storage & Cache';
+
+  @override
+  String get cacheSummaryTitle => 'Cache overview';
+
+  @override
+  String get cacheSummarySubtitle =>
+      'Clearing cache will not remove downloaded music files.';
+
+  @override
+  String cacheEstimatedTotal(String size) {
+    return 'Estimated cache usage: $size';
+  }
+
+  @override
+  String get cacheSectionStorage => 'Cached Data';
+
+  @override
+  String get cacheSectionMaintenance => 'Maintenance';
+
+  @override
+  String get cacheAppDirectory => 'App cache directory';
+
+  @override
+  String get cacheAppDirectoryDesc =>
+      'HTTP responses, WebView data, and other temporary app data.';
+
+  @override
+  String get cacheTempDirectory => 'Temporary directory';
+
+  @override
+  String get cacheTempDirectoryDesc =>
+      'Temporary files from downloads and audio conversion.';
+
+  @override
+  String get cacheCoverImage => 'Cover image cache';
+
+  @override
+  String get cacheCoverImageDesc =>
+      'Downloaded album and track cover art. Will re-download when viewed.';
+
+  @override
+  String get cacheLibraryCover => 'Library cover cache';
+
+  @override
+  String get cacheLibraryCoverDesc =>
+      'Cover art extracted from local music files. Will re-extract on next scan.';
+
+  @override
+  String get cacheExploreFeed => 'Explore feed cache';
+
+  @override
+  String get cacheExploreFeedDesc =>
+      'Explore tab content (new releases, trending). Will refresh on next visit.';
+
+  @override
+  String get cacheTrackLookup => 'Track lookup cache';
+
+  @override
+  String get cacheTrackLookupDesc =>
+      'Spotify/Deezer track ID lookups. Clearing may slow next few searches.';
+
+  @override
+  String get cacheCleanupUnusedDesc =>
+      'Remove orphaned download history and library entries for missing files.';
+
+  @override
+  String get cacheNoData => 'No cached data';
+
+  @override
+  String cacheSizeWithFiles(String size, int count) {
+    return '$size in $count files';
+  }
+
+  @override
+  String cacheSizeOnly(String size) {
+    return '$size';
+  }
+
+  @override
+  String cacheEntries(int count) {
+    return '$count entries';
+  }
+
+  @override
+  String cacheClearSuccess(String target) {
+    return 'Cleared: $target';
+  }
+
+  @override
+  String get cacheClearConfirmTitle => 'Clear cache?';
+
+  @override
+  String cacheClearConfirmMessage(String target) {
+    return 'This will clear cached data for $target. Downloaded music files will not be deleted.';
+  }
+
+  @override
+  String get cacheClearAllConfirmTitle => 'Clear all cache?';
+
+  @override
+  String get cacheClearAllConfirmMessage =>
+      'This will clear all cache categories on this page. Downloaded music files will not be deleted.';
+
+  @override
+  String get cacheClearAll => 'Clear all cache';
+
+  @override
+  String get cacheCleanupUnused => 'Cleanup unused data';
+
+  @override
+  String get cacheCleanupUnusedSubtitle =>
+      'Remove orphaned download history and missing library entries';
+
+  @override
+  String cacheCleanupResult(int downloadCount, int libraryCount) {
+    return 'Cleanup completed: $downloadCount orphaned downloads, $libraryCount missing library entries';
+  }
+
+  @override
+  String get cacheRefreshStats => 'Refresh stats';
+
+  @override
+  String get trackSaveCoverArt => 'Save Cover Art';
+
+  @override
+  String get trackSaveCoverArtSubtitle => 'Save album art as .jpg file';
+
+  @override
+  String get trackSaveLyrics => 'Save Lyrics (.lrc)';
+
+  @override
+  String get trackSaveLyricsSubtitle => 'Fetch and save lyrics as .lrc file';
+
+  @override
+  String get trackSaveLyricsProgress => 'Saving lyrics...';
+
+  @override
+  String get trackReEnrich => 'Re-enrich Metadata';
+
+  @override
+  String get trackReEnrichSubtitle =>
+      'Re-embed metadata without re-downloading';
+
+  @override
+  String get trackReEnrichOnlineSubtitle =>
+      'Search metadata online and embed into file';
+
+  @override
+  String get trackEditMetadata => 'Edit Metadata';
+
+  @override
+  String trackCoverSaved(String fileName) {
+    return 'Cover art saved to $fileName';
+  }
+
+  @override
+  String get trackCoverNoSource => 'No cover art source available';
+
+  @override
+  String trackLyricsSaved(String fileName) {
+    return 'Lyrics saved to $fileName';
+  }
+
+  @override
+  String get trackReEnrichProgress => 'Re-enriching metadata...';
+
+  @override
+  String get trackReEnrichSearching => 'Searching metadata online...';
+
+  @override
+  String get trackReEnrichSuccess => 'Metadata re-enriched successfully';
+
+  @override
+  String get trackReEnrichFfmpegFailed => 'FFmpeg metadata embed failed';
+
+  @override
+  String trackSaveFailed(String error) {
+    return 'Failed: $error';
+  }
+
+  @override
+  String get trackConvertFormat => 'Convert Format';
+
+  @override
+  String get trackConvertFormatSubtitle => 'Convert to MP3 or Opus';
+
+  @override
+  String get trackConvertTitle => 'Convert Audio';
+
+  @override
+  String get trackConvertTargetFormat => 'Target Format';
+
+  @override
+  String get trackConvertBitrate => 'Bitrate';
+
+  @override
+  String get trackConvertConfirmTitle => 'Confirm Conversion';
+
+  @override
+  String trackConvertConfirmMessage(
+    String sourceFormat,
+    String targetFormat,
+    String bitrate,
+  ) {
+    return 'Convert from $sourceFormat to $targetFormat at $bitrate?\n\nThe original file will be deleted after conversion.';
+  }
+
+  @override
+  String get trackConvertConverting => 'Converting audio...';
+
+  @override
+  String trackConvertSuccess(String format) {
+    return 'Converted to $format successfully';
+  }
+
+  @override
+  String get trackConvertFailed => 'Conversion failed';
 }

lib/l10n/arb/app_en.arb

@@ -9,8 +9,10 @@
 
   "navHome": "Home",
   "@navHome": {"description": "Bottom navigation - Home tab"},
+  "navLibrary": "Library",
+  "@navLibrary": {"description": "Bottom navigation - Library tab"},
   "navHistory": "History",
-  "@navHistory": {"description": "Bottom navigation - History tab"},
+  "@navHistory": {"description": "Bottom navigation - History tab (legacy)"},
   "navSettings": "Settings",
   "@navSettings": {"description": "Bottom navigation - Settings tab"},
   "navStore": "Store",
@@ -239,6 +241,8 @@
   "@optionsSpotifyCredentialsRequired": {"description": "Prompt to set up credentials"},
   "optionsSpotifyWarning": "Spotify requires your own API credentials. Get them free from developer.spotify.com",
   "@optionsSpotifyWarning": {"description": "Info about Spotify API requirement"},
+  "optionsSpotifyDeprecationWarning": "Spotify search will be deprecated on March 3, 2026 due to Spotify API changes. Please switch to Deezer.",
+  "@optionsSpotifyDeprecationWarning": {"description": "Warning about Spotify API deprecation"},
 
   "extensionsTitle": "Extensions",
   "@extensionsTitle": {"description": "Extensions page title"},
@@ -322,10 +326,6 @@
   "@aboutSocial": {"description": "Section for social links"},
   "aboutSupport": "Support",
   "@aboutSupport": {"description": "Section for support/donation links"},
-  "aboutBuyMeCoffee": "Buy me a coffee",
-  "@aboutBuyMeCoffee": {"description": "Donation link"},
-  "aboutBuyMeCoffeeSubtitle": "Support development on Ko-fi",
-  "@aboutBuyMeCoffeeSubtitle": {"description": "Subtitle for donation"},
   "aboutApp": "App",
   "@aboutApp": {"description": "Section for app info"},
   "aboutVersion": "Version",
@@ -344,6 +344,10 @@
   "@aboutDabMusic": {"description": "Name of Qobuz API service - DO NOT TRANSLATE"},
   "aboutDabMusicDesc": "The best Qobuz streaming API. Hi-Res downloads wouldn't be possible without this!",
   "@aboutDabMusicDesc": {"description": "Credit for DAB Music API"},
+  "aboutSpotiSaver": "SpotiSaver",
+  "@aboutSpotiSaver": {"description": "Name of SpotiSaver API service - DO NOT TRANSLATE"},
+  "aboutSpotiSaverDesc": "Tidal Hi-Res FLAC streaming endpoints. A key piece of the lossless puzzle!",
+  "@aboutSpotiSaverDesc": {"description": "Credit for SpotiSaver API"},
   "aboutAppDescription": "Download Spotify tracks in lossless quality from Tidal, Qobuz, and Amazon Music.",
   "@aboutAppDescription": {"description": "App description in header card"},
 
@@ -481,8 +485,10 @@
   "@setupChooseFromFiles": {"description": "iOS file picker option"},
   "setupChooseFromFilesSubtitle": "Select iCloud or other location",
   "@setupChooseFromFilesSubtitle": {"description": "Subtitle for file picker"},
-  "setupIosEmptyFolderWarning": "iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.",
+"setupIosEmptyFolderWarning": "iOS limitation: Empty folders cannot be selected. Choose a folder with at least one file.",
   "@setupIosEmptyFolderWarning": {"description": "iOS folder selection warning"},
+  "setupIcloudNotSupported": "iCloud Drive is not supported. Please use the app Documents folder.",
+  "@setupIcloudNotSupported": {"description": "Error when user selects iCloud Drive on iOS"},
   "setupDownloadInFlac": "Download Spotify tracks in FLAC",
   "@setupDownloadInFlac": {"description": "App tagline in setup"},
   "setupStepStorage": "Storage",
@@ -668,6 +674,13 @@
       "trackName": {"type": "String"}
     }
   },
+  "snackbarAlreadyInLibrary": "\"{trackName}\" already exists in your library",
+  "@snackbarAlreadyInLibrary": {
+    "description": "Snackbar - track already exists in local library",
+    "placeholders": {
+      "trackName": {"type": "String"}
+    }
+  },
   "snackbarHistoryCleared": "History cleared",
   "@snackbarHistoryCleared": {"description": "Snackbar - history deleted"},
   "snackbarCredentialsSaved": "Credentials saved",
@@ -861,6 +874,14 @@
   "@filenameAvailablePlaceholders": {"description": "Label for placeholder list"},
   "filenameHint": "{artist} - {title}",
   "@filenameHint": {"description": "Default filename format hint"},
+  "filenameShowAdvancedTags": "Show advanced tags",
+  "@filenameShowAdvancedTags": {
+    "description": "Toggle label for showing advanced filename tags"
+  },
+  "filenameShowAdvancedTagsDescription": "Enable formatted tags for track padding and date patterns",
+  "@filenameShowAdvancedTagsDescription": {
+    "description": "Description for advanced filename tag toggle"
+  },
 
   "folderOrganization": "Folder Organization",
   "@folderOrganization": {"description": "Setting title - folder structure"},
@@ -1397,6 +1418,8 @@
   "@lossyFormatOpusSubtitle": {"description": "Opus format description"},
   "qualityNote": "Actual quality depends on track availability from the service",
   "@qualityNote": {"description": "Note about quality availability"},
+  "youtubeQualityNote": "YouTube provides lossy audio only. Not part of lossless fallback.",
+  "@youtubeQualityNote": {"description": "Note for YouTube service explaining lossy-only quality"},
 
   "downloadAskBeforeDownload": "Ask Before Download",
   "@downloadAskBeforeDownload": {"description": "Setting - show quality picker"},
@@ -1406,6 +1429,18 @@
   "@downloadSeparateSinglesFolder": {"description": "Setting - separate folder for singles"},
   "downloadAlbumFolderStructure": "Album Folder Structure",
   "@downloadAlbumFolderStructure": {"description": "Setting - album folder organization"},
+  "downloadUseAlbumArtistForFolders": "Use Album Artist for folders",
+  "@downloadUseAlbumArtistForFolders": {"description": "Setting - choose whether artist folders use Album Artist or Track Artist"},
+  "downloadUseAlbumArtistForFoldersAlbumSubtitle": "Artist folders use Album Artist when available",
+  "@downloadUseAlbumArtistForFoldersAlbumSubtitle": {"description": "Subtitle when Album Artist is used for folder naming"},
+  "downloadUseAlbumArtistForFoldersTrackSubtitle": "Artist folders use Track Artist only",
+  "@downloadUseAlbumArtistForFoldersTrackSubtitle": {"description": "Subtitle when Track Artist is used for folder naming"},
+  "downloadUsePrimaryArtistOnly": "Primary artist only for folders",
+  "@downloadUsePrimaryArtistOnly": {"description": "Setting - strip featured artists from folder name"},
+  "downloadUsePrimaryArtistOnlyEnabled": "Featured artists removed from folder name (e.g. Justin Bieber, Quavo → Justin Bieber)",
+  "@downloadUsePrimaryArtistOnlyEnabled": {"description": "Subtitle when primary artist only is enabled"},
+  "downloadUsePrimaryArtistOnlyDisabled": "Full artist string used for folder name",
+  "@downloadUsePrimaryArtistOnlyDisabled": {"description": "Subtitle when primary artist only is disabled"},
   "downloadSaveFormat": "Save Format",
   "@downloadSaveFormat": {"description": "Setting - output file format"},
   "downloadSelectService": "Select Service",
@@ -1458,10 +1493,32 @@
 
   "queueTitle": "Download Queue",
   "@queueTitle": {"description": "Queue screen title"},
-  "queueClearAll": "Clear All",
+"queueClearAll": "Clear All",
   "@queueClearAll": {"description": "Button - clear all queue items"},
   "queueClearAllMessage": "Are you sure you want to clear all downloads?",
   "@queueClearAllMessage": {"description": "Clear queue confirmation"},
+  "queueExportFailed": "Export",
+  "@queueExportFailed": {"description": "Button - export failed downloads to TXT"},
+  "queueExportFailedSuccess": "Failed downloads exported to TXT file",
+  "@queueExportFailedSuccess": {"description": "Success message after exporting failed downloads"},
+  "queueExportFailedClear": "Clear Failed",
+  "@queueExportFailedClear": {"description": "Action to clear failed downloads after export"},
+  "queueExportFailedError": "Failed to export downloads",
+  "@queueExportFailedError": {"description": "Error message when export fails"},
+  "settingsAutoExportFailed": "Auto-export failed downloads",
+  "@settingsAutoExportFailed": {"description": "Setting toggle for auto-export"},
+  "settingsAutoExportFailedSubtitle": "Save failed downloads to TXT file automatically",
+  "@settingsAutoExportFailedSubtitle": {"description": "Subtitle for auto-export setting"},
+
+  "settingsDownloadNetwork": "Download Network",
+  "@settingsDownloadNetwork": {"description": "Setting for network type preference"},
+  "settingsDownloadNetworkAny": "WiFi + Mobile Data",
+  "@settingsDownloadNetworkAny": {"description": "Network option - use any connection"},
+  "settingsDownloadNetworkWifiOnly": "WiFi Only",
+  "@settingsDownloadNetworkWifiOnly": {"description": "Network option - only use WiFi"},
+  "settingsDownloadNetworkSubtitle": "Choose which network to use for downloads. When set to WiFi Only, downloads will pause on mobile data.",
+  "@settingsDownloadNetworkSubtitle": {"description": "Subtitle explaining network preference"},
+
   "queueEmpty": "No downloads in queue",
   "@queueEmpty": {"description": "Empty queue state title"},
   "queueEmptySubtitle": "Add tracks from the home screen",
@@ -1557,6 +1614,12 @@
   "@recentTypeSong": {"description": "Recent access item type - song/track"},
   "recentTypePlaylist": "Playlist",
   "@recentTypePlaylist": {"description": "Recent access item type - playlist"},
+  "recentEmpty": "No recent items yet",
+  "@recentEmpty": {"description": "Empty state text for recent access list"},
+  "recentShowAllDownloads": "Show All Downloads",
+  "@recentShowAllDownloads": {
+    "description": "Button label to unhide hidden downloads in recent access"
+  },
 
   "recentPlaylistInfo": "Playlist: {name}",
   "@recentPlaylistInfo": {
@@ -1661,5 +1724,508 @@
   "allFilesAccessDeniedMessage": "Permission was denied. Please enable 'All files access' manually in system settings.",
   "@allFilesAccessDeniedMessage": {"description": "Message when permission is permanently denied"},
   "allFilesAccessDisabledMessage": "All Files Access disabled. The app will use limited storage access.",
-  "@allFilesAccessDisabledMessage": {"description": "Snackbar message when user disables all files access"}
+  "@allFilesAccessDisabledMessage": {"description": "Snackbar message when user disables all files access"},
+
+  "settingsLocalLibrary": "Local Library",
+  "@settingsLocalLibrary": {"description": "Settings menu item - local library"},
+  "settingsLocalLibrarySubtitle": "Scan music & detect duplicates",
+  "@settingsLocalLibrarySubtitle": {"description": "Subtitle for local library settings"},
+  "settingsCache": "Storage & Cache",
+  "@settingsCache": {"description": "Settings menu item - cache management"},
+  "settingsCacheSubtitle": "View size and clear cached data",
+  "@settingsCacheSubtitle": {"description": "Subtitle for cache management menu"},
+  "libraryTitle": "Local Library",
+  "@libraryTitle": {"description": "Library settings page title"},
+  "libraryStatus": "Library Status",
+  "@libraryStatus": {"description": "Section header for library status"},
+  "libraryScanSettings": "Scan Settings",
+  "@libraryScanSettings": {"description": "Section header for scan settings"},
+  "libraryEnableLocalLibrary": "Enable Local Library",
+  "@libraryEnableLocalLibrary": {"description": "Toggle to enable library scanning"},
+  "libraryEnableLocalLibrarySubtitle": "Scan and track your existing music",
+  "@libraryEnableLocalLibrarySubtitle": {"description": "Subtitle for enable toggle"},
+  "libraryFolder": "Library Folder",
+  "@libraryFolder": {"description": "Folder selection setting"},
+  "libraryFolderHint": "Tap to select folder",
+  "@libraryFolderHint": {"description": "Placeholder when no folder selected"},
+  "libraryShowDuplicateIndicator": "Show Duplicate Indicator",
+  "@libraryShowDuplicateIndicator": {"description": "Toggle for duplicate indicator in search"},
+  "libraryShowDuplicateIndicatorSubtitle": "Show when searching for existing tracks",
+  "@libraryShowDuplicateIndicatorSubtitle": {"description": "Subtitle for duplicate indicator toggle"},
+  "libraryActions": "Actions",
+  "@libraryActions": {"description": "Section header for library actions"},
+  "libraryScan": "Scan Library",
+  "@libraryScan": {"description": "Button to start library scan"},
+  "libraryScanSubtitle": "Scan for audio files",
+  "@libraryScanSubtitle": {"description": "Subtitle for scan button"},
+  "libraryScanSelectFolderFirst": "Select a folder first",
+  "@libraryScanSelectFolderFirst": {"description": "Message when trying to scan without folder"},
+  "libraryCleanupMissingFiles": "Cleanup Missing Files",
+  "@libraryCleanupMissingFiles": {"description": "Button to remove entries for missing files"},
+  "libraryCleanupMissingFilesSubtitle": "Remove entries for files that no longer exist",
+  "@libraryCleanupMissingFilesSubtitle": {"description": "Subtitle for cleanup button"},
+  "libraryClear": "Clear Library",
+  "@libraryClear": {"description": "Button to clear all library entries"},
+  "libraryClearSubtitle": "Remove all scanned tracks",
+  "@libraryClearSubtitle": {"description": "Subtitle for clear button"},
+  "libraryClearConfirmTitle": "Clear Library",
+  "@libraryClearConfirmTitle": {"description": "Dialog title for clear confirmation"},
+  "libraryClearConfirmMessage": "This will remove all scanned tracks from your library. Your actual music files will not be deleted.",
+  "@libraryClearConfirmMessage": {"description": "Dialog message for clear confirmation"},
+  "libraryAbout": "About Local Library",
+  "@libraryAbout": {"description": "Section header for about info"},
+  "libraryAboutDescription": "Scans your existing music collection to detect duplicates when downloading. Supports FLAC, M4A, MP3, Opus, and OGG formats. Metadata is read from file tags when available.",
+  "@libraryAboutDescription": {"description": "Description of local library feature"},
+  "libraryTracksCount": "{count} tracks",
+  "@libraryTracksCount": {
+    "description": "Track count in library",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "libraryLastScanned": "Last scanned: {time}",
+  "@libraryLastScanned": {
+    "description": "Last scan time display",
+    "placeholders": {
+      "time": {"type": "String"}
+    }
+  },
+  "libraryLastScannedNever": "Never",
+  "@libraryLastScannedNever": {"description": "Shown when library has never been scanned"},
+  "libraryScanning": "Scanning...",
+  "@libraryScanning": {"description": "Status during scan"},
+  "libraryScanProgress": "{progress}% of {total} files",
+  "@libraryScanProgress": {
+    "description": "Scan progress display",
+    "placeholders": {
+      "progress": {"type": "String"},
+      "total": {"type": "int"}
+    }
+  },
+  "libraryInLibrary": "In Library",
+  "@libraryInLibrary": {"description": "Badge shown on tracks that exist in local library"},
+  "libraryRemovedMissingFiles": "Removed {count} missing files from library",
+  "@libraryRemovedMissingFiles": {
+    "description": "Snackbar after cleanup",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "libraryCleared": "Library cleared",
+  "@libraryCleared": {"description": "Snackbar after clearing library"},
+  "libraryStorageAccessRequired": "Storage Access Required",
+  "@libraryStorageAccessRequired": {"description": "Dialog title for storage permission"},
+  "libraryStorageAccessMessage": "SpotiFLAC needs storage access to scan your music library. Please grant permission in settings.",
+  "@libraryStorageAccessMessage": {"description": "Dialog message for storage permission"},
+  "libraryFolderNotExist": "Selected folder does not exist",
+  "@libraryFolderNotExist": {"description": "Error when folder doesn't exist"},
+  "librarySourceDownloaded": "Downloaded",
+  "@librarySourceDownloaded": {"description": "Badge for tracks downloaded via SpotiFLAC"},
+  "librarySourceLocal": "Local",
+  "@librarySourceLocal": {"description": "Badge for tracks from local library scan"},
+  "libraryFilterAll": "All",
+  "@libraryFilterAll": {"description": "Filter chip - show all library items"},
+  "libraryFilterDownloaded": "Downloaded",
+  "@libraryFilterDownloaded": {"description": "Filter chip - show only downloaded items"},
+  "libraryFilterLocal": "Local",
+  "@libraryFilterLocal": {"description": "Filter chip - show only local library items"},
+
+  "libraryFilterTitle": "Filters",
+  "@libraryFilterTitle": {"description": "Filter bottom sheet title"},
+  "libraryFilterReset": "Reset",
+  "@libraryFilterReset": {"description": "Reset all filters button"},
+  "libraryFilterApply": "Apply",
+  "@libraryFilterApply": {"description": "Apply filters button"},
+  "libraryFilterSource": "Source",
+  "@libraryFilterSource": {"description": "Filter section - source type"},
+  "libraryFilterQuality": "Quality",
+  "@libraryFilterQuality": {"description": "Filter section - audio quality"},
+  "libraryFilterQualityHiRes": "Hi-Res (24bit)",
+  "@libraryFilterQualityHiRes": {"description": "Filter option - high resolution audio"},
+  "libraryFilterQualityCD": "CD (16bit)",
+  "@libraryFilterQualityCD": {"description": "Filter option - CD quality audio"},
+  "libraryFilterQualityLossy": "Lossy",
+  "@libraryFilterQualityLossy": {"description": "Filter option - lossy compressed audio"},
+  "libraryFilterFormat": "Format",
+  "@libraryFilterFormat": {"description": "Filter section - file format"},
+  "libraryFilterDate": "Date Added",
+  "@libraryFilterDate": {"description": "Filter section - date range"},
+  "libraryFilterDateToday": "Today",
+  "@libraryFilterDateToday": {"description": "Filter option - today only"},
+  "libraryFilterDateWeek": "This Week",
+  "@libraryFilterDateWeek": {"description": "Filter option - this week"},
+  "libraryFilterDateMonth": "This Month",
+  "@libraryFilterDateMonth": {"description": "Filter option - this month"},
+  "libraryFilterDateYear": "This Year",
+  "@libraryFilterDateYear": {"description": "Filter option - this year"},
+  "libraryFilterSort": "Sort",
+  "@libraryFilterSort": {"description": "Filter section - sort order"},
+  "libraryFilterSortLatest": "Latest",
+  "@libraryFilterSortLatest": {"description": "Sort option - newest first"},
+  "libraryFilterSortOldest": "Oldest",
+  "@libraryFilterSortOldest": {"description": "Sort option - oldest first"},
+  "libraryFilterActive": "{count} filter(s) active",
+  "@libraryFilterActive": {
+    "description": "Badge showing number of active filters",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+
+  "timeJustNow": "Just now",
+  "@timeJustNow": {"description": "Relative time - less than a minute ago"},
+  "timeMinutesAgo": "{count, plural, =1{1 minute ago} other{{count} minutes ago}}",
+  "@timeMinutesAgo": {
+    "description": "Relative time - minutes ago",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "timeHoursAgo": "{count, plural, =1{1 hour ago} other{{count} hours ago}}",
+  "@timeHoursAgo": {
+    "description": "Relative time - hours ago",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+
+  "storageSwitchTitle": "Switch Storage Mode",
+  "@storageSwitchTitle": {"description": "Dialog title when switching storage mode"},
+  "storageSwitchToSafTitle": "Switch to SAF Storage?",
+  "@storageSwitchToSafTitle": {"description": "Dialog title when switching to SAF"},
+  "storageSwitchToAppTitle": "Switch to App Storage?",
+  "@storageSwitchToAppTitle": {"description": "Dialog title when switching to app storage"},
+  "storageSwitchToSafMessage": "Your existing downloads will remain in the current location and stay accessible.\n\nNew downloads will be saved to your selected SAF folder.",
+  "@storageSwitchToSafMessage": {"description": "Explanation when switching to SAF"},
+  "storageSwitchToAppMessage": "Your existing downloads will remain in the current SAF location and stay accessible.\n\nNew downloads will be saved to Music/SpotiFLAC folder.",
+  "@storageSwitchToAppMessage": {"description": "Explanation when switching to app storage"},
+  "storageSwitchExistingDownloads": "Existing Downloads",
+  "@storageSwitchExistingDownloads": {"description": "Section header for existing downloads info"},
+  "storageSwitchExistingDownloadsInfo": "{count} tracks in {mode} storage",
+  "@storageSwitchExistingDownloadsInfo": {
+    "description": "Info about existing downloads count",
+    "placeholders": {
+      "count": {"type": "int"},
+      "mode": {"type": "String"}
+    }
+  },
+  "storageSwitchNewDownloads": "New Downloads",
+  "@storageSwitchNewDownloads": {"description": "Section header for new downloads info"},
+  "storageSwitchNewDownloadsLocation": "Will be saved to: {location}",
+  "@storageSwitchNewDownloadsLocation": {
+    "description": "Shows where new downloads will go",
+    "placeholders": {
+      "location": {"type": "String"}
+    }
+  },
+  "storageSwitchContinue": "Continue",
+  "@storageSwitchContinue": {"description": "Button to proceed with storage switch"},
+  "storageSwitchSelectFolder": "Select SAF Folder",
+  "@storageSwitchSelectFolder": {"description": "Button to select SAF folder"},
+  "storageAppStorage": "App Storage",
+  "@storageAppStorage": {"description": "Label for app storage mode"},
+  "storageSafStorage": "SAF Storage",
+  "@storageSafStorage": {"description": "Label for SAF storage mode"},
+  "storageModeBadge": "Storage: {mode}",
+  "@storageModeBadge": {
+    "description": "Badge showing storage mode for a track",
+    "placeholders": {
+      "mode": {"type": "String"}
+    }
+  },
+  "storageStatsTitle": "Storage Statistics",
+  "@storageStatsTitle": {"description": "Section title for storage stats"},
+  "storageStatsAppCount": "{count} tracks in App Storage",
+  "@storageStatsAppCount": {
+    "description": "Count of tracks in app storage",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "storageStatsSafCount": "{count} tracks in SAF Storage",
+  "@storageStatsSafCount": {
+    "description": "Count of tracks in SAF storage",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "storageModeInfo": "Your files are stored in multiple locations",
+  "@storageModeInfo": {"description": "Info when user has files in both storage modes"},
+
+  "tutorialWelcomeTitle": "Welcome to SpotiFLAC!",
+  "@tutorialWelcomeTitle": {"description": "Tutorial welcome page title"},
+  "tutorialWelcomeDesc": "Let's learn how to download your favorite music in lossless quality. This quick tutorial will show you the basics.",
+  "@tutorialWelcomeDesc": {"description": "Tutorial welcome page description"},
+  "tutorialWelcomeTip1": "Download music from Spotify, Deezer, or paste any supported URL",
+  "@tutorialWelcomeTip1": {"description": "Tutorial welcome tip 1"},
+  "tutorialWelcomeTip2": "Get FLAC quality audio from Tidal, Qobuz, or Amazon Music",
+  "@tutorialWelcomeTip2": {"description": "Tutorial welcome tip 2"},
+  "tutorialWelcomeTip3": "Automatic metadata, cover art, and lyrics embedding",
+  "@tutorialWelcomeTip3": {"description": "Tutorial welcome tip 3"},
+
+  "tutorialSearchTitle": "Finding Music",
+  "@tutorialSearchTitle": {"description": "Tutorial search page title"},
+  "tutorialSearchDesc": "There are two easy ways to find music you want to download.",
+  "@tutorialSearchDesc": {"description": "Tutorial search page description"},
+  "tutorialSearchTip1": "Paste a Spotify or Deezer URL directly in the search box",
+  "@tutorialSearchTip1": {"description": "Tutorial search tip 1"},
+  "tutorialSearchTip2": "Or type the song name, artist, or album to search",
+  "@tutorialSearchTip2": {"description": "Tutorial search tip 2"},
+  "tutorialSearchTip3": "Supports tracks, albums, playlists, and artist pages",
+  "@tutorialSearchTip3": {"description": "Tutorial search tip 3"},
+
+  "tutorialDownloadTitle": "Downloading Music",
+  "@tutorialDownloadTitle": {"description": "Tutorial download page title"},
+  "tutorialDownloadDesc": "Downloading music is simple and fast. Here's how it works.",
+  "@tutorialDownloadDesc": {"description": "Tutorial download page description"},
+  "tutorialDownloadTip1": "Tap the download button next to any track to start downloading",
+  "@tutorialDownloadTip1": {"description": "Tutorial download tip 1"},
+  "tutorialDownloadTip2": "Choose your preferred quality (FLAC, Hi-Res, or MP3)",
+  "@tutorialDownloadTip2": {"description": "Tutorial download tip 2"},
+  "tutorialDownloadTip3": "Download entire albums or playlists with one tap",
+  "@tutorialDownloadTip3": {"description": "Tutorial download tip 3"},
+
+  "tutorialLibraryTitle": "Your Library",
+  "@tutorialLibraryTitle": {"description": "Tutorial library page title"},
+  "tutorialLibraryDesc": "All your downloaded music is organized in the Library tab.",
+  "@tutorialLibraryDesc": {"description": "Tutorial library page description"},
+  "tutorialLibraryTip1": "View download progress and queue in the Library tab",
+  "@tutorialLibraryTip1": {"description": "Tutorial library tip 1"},
+  "tutorialLibraryTip2": "Tap any track to play it with your music player",
+  "@tutorialLibraryTip2": {"description": "Tutorial library tip 2"},
+  "tutorialLibraryTip3": "Switch between list and grid view for better browsing",
+  "@tutorialLibraryTip3": {"description": "Tutorial library tip 3"},
+
+  "tutorialExtensionsTitle": "Extensions",
+  "@tutorialExtensionsTitle": {"description": "Tutorial extensions page title"},
+  "tutorialExtensionsDesc": "Extend the app's capabilities with community extensions.",
+  "@tutorialExtensionsDesc": {"description": "Tutorial extensions page description"},
+  "tutorialExtensionsTip1": "Browse the Store tab to discover useful extensions",
+  "@tutorialExtensionsTip1": {"description": "Tutorial extensions tip 1"},
+  "tutorialExtensionsTip2": "Add new download providers or search sources",
+  "@tutorialExtensionsTip2": {"description": "Tutorial extensions tip 2"},
+  "tutorialExtensionsTip3": "Get lyrics, enhanced metadata, and more features",
+  "@tutorialExtensionsTip3": {"description": "Tutorial extensions tip 3"},
+
+  "tutorialSettingsTitle": "Customize Your Experience",
+  "@tutorialSettingsTitle": {"description": "Tutorial settings page title"},
+  "tutorialSettingsDesc": "Personalize the app in Settings to match your preferences.",
+  "@tutorialSettingsDesc": {"description": "Tutorial settings page description"},
+  "tutorialSettingsTip1": "Change download location and folder organization",
+  "@tutorialSettingsTip1": {"description": "Tutorial settings tip 1"},
+  "tutorialSettingsTip2": "Set default audio quality and format preferences",
+  "@tutorialSettingsTip2": {"description": "Tutorial settings tip 2"},
+  "tutorialSettingsTip3": "Customize app theme and appearance",
+  "@tutorialSettingsTip3": {"description": "Tutorial settings tip 3"},
+
+  "tutorialReadyMessage": "You're all set! Start downloading your favorite music now.",
+  "@tutorialReadyMessage": {"description": "Tutorial completion message"},
+  "tutorialExample": "EXAMPLE",
+  "@tutorialExample": {"description": "Example label in tutorial"},
+
+  "libraryForceFullScan": "Force Full Scan",
+  "@libraryForceFullScan": {"description": "Button to force a complete rescan of library"},
+  "libraryForceFullScanSubtitle": "Rescan all files, ignoring cache",
+  "@libraryForceFullScanSubtitle": {"description": "Subtitle for force full scan button"},
+
+  "cleanupOrphanedDownloads": "Cleanup Orphaned Downloads",
+  "@cleanupOrphanedDownloads": {"description": "Button to remove history entries for deleted files"},
+  "cleanupOrphanedDownloadsSubtitle": "Remove history entries for files that no longer exist",
+  "@cleanupOrphanedDownloadsSubtitle": {"description": "Subtitle for orphaned cleanup button"},
+  "cleanupOrphanedDownloadsResult": "Removed {count} orphaned entries from history",
+  "@cleanupOrphanedDownloadsResult": {
+    "description": "Snackbar after orphan cleanup",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "cleanupOrphanedDownloadsNone": "No orphaned entries found",
+  "@cleanupOrphanedDownloadsNone": {"description": "Snackbar when no orphans found"},
+
+  "cacheTitle": "Storage & Cache",
+  "@cacheTitle": {"description": "Cache management page title"},
+  "cacheSummaryTitle": "Cache overview",
+  "@cacheSummaryTitle": {"description": "Heading for cache summary card"},
+  "cacheSummarySubtitle": "Clearing cache will not remove downloaded music files.",
+  "@cacheSummarySubtitle": {"description": "Helper text for cache summary card"},
+  "cacheEstimatedTotal": "Estimated cache usage: {size}",
+  "@cacheEstimatedTotal": {
+    "description": "Total cache size shown in summary",
+    "placeholders": {
+      "size": {"type": "String"}
+    }
+  },
+  "cacheSectionStorage": "Cached Data",
+  "@cacheSectionStorage": {"description": "Section header for cache entries"},
+  "cacheSectionMaintenance": "Maintenance",
+  "@cacheSectionMaintenance": {"description": "Section header for cleanup actions"},
+  "cacheAppDirectory": "App cache directory",
+  "@cacheAppDirectory": {"description": "Cache item title for app cache directory"},
+  "cacheAppDirectoryDesc": "HTTP responses, WebView data, and other temporary app data.",
+  "@cacheAppDirectoryDesc": {"description": "Description of what app cache directory contains"},
+  "cacheTempDirectory": "Temporary directory",
+  "@cacheTempDirectory": {"description": "Cache item title for temporary files directory"},
+  "cacheTempDirectoryDesc": "Temporary files from downloads and audio conversion.",
+  "@cacheTempDirectoryDesc": {"description": "Description of what temporary directory contains"},
+  "cacheCoverImage": "Cover image cache",
+  "@cacheCoverImage": {"description": "Cache item title for persistent cover images"},
+  "cacheCoverImageDesc": "Downloaded album and track cover art. Will re-download when viewed.",
+  "@cacheCoverImageDesc": {"description": "Description of what cover image cache contains"},
+  "cacheLibraryCover": "Library cover cache",
+  "@cacheLibraryCover": {"description": "Cache item title for local library cover art images"},
+  "cacheLibraryCoverDesc": "Cover art extracted from local music files. Will re-extract on next scan.",
+  "@cacheLibraryCoverDesc": {"description": "Description of what library cover cache contains"},
+  "cacheExploreFeed": "Explore feed cache",
+  "@cacheExploreFeed": {"description": "Cache item title for explore home feed cache"},
+  "cacheExploreFeedDesc": "Explore tab content (new releases, trending). Will refresh on next visit.",
+  "@cacheExploreFeedDesc": {"description": "Description of what explore feed cache contains"},
+  "cacheTrackLookup": "Track lookup cache",
+  "@cacheTrackLookup": {"description": "Cache item title for track ID lookup cache"},
+  "cacheTrackLookupDesc": "Spotify/Deezer track ID lookups. Clearing may slow next few searches.",
+  "@cacheTrackLookupDesc": {"description": "Description of what track lookup cache contains"},
+  "cacheCleanupUnusedDesc": "Remove orphaned download history and library entries for missing files.",
+  "@cacheCleanupUnusedDesc": {"description": "Description of what cleanup unused data does"},
+  "cacheNoData": "No cached data",
+  "@cacheNoData": {"description": "Label when cache category has no data"},
+  "cacheSizeWithFiles": "{size} in {count} files",
+  "@cacheSizeWithFiles": {
+    "description": "Cache size and file count",
+    "placeholders": {
+      "size": {"type": "String"},
+      "count": {"type": "int"}
+    }
+  },
+  "cacheSizeOnly": "{size}",
+  "@cacheSizeOnly": {
+    "description": "Cache size only",
+    "placeholders": {
+      "size": {"type": "String"}
+    }
+  },
+  "cacheEntries": "{count} entries",
+  "@cacheEntries": {
+    "description": "Track cache entry count",
+    "placeholders": {
+      "count": {"type": "int"}
+    }
+  },
+  "cacheClearSuccess": "Cleared: {target}",
+  "@cacheClearSuccess": {
+    "description": "Snackbar after clearing selected cache",
+    "placeholders": {
+      "target": {"type": "String"}
+    }
+  },
+  "cacheClearConfirmTitle": "Clear cache?",
+  "@cacheClearConfirmTitle": {"description": "Dialog title before clearing one cache category"},
+  "cacheClearConfirmMessage": "This will clear cached data for {target}. Downloaded music files will not be deleted.",
+  "@cacheClearConfirmMessage": {
+    "description": "Dialog message before clearing selected cache",
+    "placeholders": {
+      "target": {"type": "String"}
+    }
+  },
+  "cacheClearAllConfirmTitle": "Clear all cache?",
+  "@cacheClearAllConfirmTitle": {"description": "Dialog title before clearing all caches"},
+  "cacheClearAllConfirmMessage": "This will clear all cache categories on this page. Downloaded music files will not be deleted.",
+  "@cacheClearAllConfirmMessage": {"description": "Dialog message before clearing all caches"},
+  "cacheClearAll": "Clear all cache",
+  "@cacheClearAll": {"description": "Button label to clear all caches"},
+  "cacheCleanupUnused": "Cleanup unused data",
+  "@cacheCleanupUnused": {"description": "Action title for cleaning unused entries"},
+  "cacheCleanupUnusedSubtitle": "Remove orphaned download history and missing library entries",
+  "@cacheCleanupUnusedSubtitle": {"description": "Subtitle for cleanup unused data action"},
+  "cacheCleanupResult": "Cleanup completed: {downloadCount} orphaned downloads, {libraryCount} missing library entries",
+  "@cacheCleanupResult": {
+    "description": "Snackbar after unused data cleanup",
+    "placeholders": {
+      "downloadCount": {"type": "int"},
+      "libraryCount": {"type": "int"}
+    }
+  },
+  "cacheRefreshStats": "Refresh stats",
+  "@cacheRefreshStats": {"description": "Button label to refresh cache statistics"},
+
+  "trackSaveCoverArt": "Save Cover Art",
+  "@trackSaveCoverArt": {"description": "Menu action - save album cover art as file"},
+  "trackSaveCoverArtSubtitle": "Save album art as .jpg file",
+  "@trackSaveCoverArtSubtitle": {"description": "Subtitle for save cover art action"},
+  "trackSaveLyrics": "Save Lyrics (.lrc)",
+  "@trackSaveLyrics": {"description": "Menu action - save lyrics as .lrc file"},
+  "trackSaveLyricsSubtitle": "Fetch and save lyrics as .lrc file",
+  "@trackSaveLyricsSubtitle": {"description": "Subtitle for save lyrics action"},
+  "trackSaveLyricsProgress": "Saving lyrics...",
+  "@trackSaveLyricsProgress": {"description": "Snackbar while saving lyrics to file"},
+  "trackReEnrich": "Re-enrich Metadata",
+  "@trackReEnrich": {"description": "Menu action - re-embed metadata into audio file"},
+  "trackReEnrichSubtitle": "Re-embed metadata without re-downloading",
+  "@trackReEnrichSubtitle": {"description": "Subtitle for re-enrich metadata action"},
+  "trackReEnrichOnlineSubtitle": "Search metadata online and embed into file",
+  "@trackReEnrichOnlineSubtitle": {"description": "Subtitle for re-enrich metadata action for local items"},
+  "trackEditMetadata": "Edit Metadata",
+  "@trackEditMetadata": {"description": "Menu action - edit embedded metadata"},
+  "trackCoverSaved": "Cover art saved to {fileName}",
+  "@trackCoverSaved": {
+    "description": "Snackbar after cover art saved",
+    "placeholders": {
+      "fileName": {"type": "String"}
+    }
+  },
+  "trackCoverNoSource": "No cover art source available",
+  "@trackCoverNoSource": {"description": "Snackbar when no cover art URL or embedded cover"},
+  "trackLyricsSaved": "Lyrics saved to {fileName}",
+  "@trackLyricsSaved": {
+    "description": "Snackbar after lyrics saved",
+    "placeholders": {
+      "fileName": {"type": "String"}
+    }
+  },
+  "trackReEnrichProgress": "Re-enriching metadata...",
+  "@trackReEnrichProgress": {"description": "Snackbar while re-enriching metadata"},
+  "trackReEnrichSearching": "Searching metadata online...",
+  "@trackReEnrichSearching": {"description": "Snackbar while searching metadata from internet for local items"},
+  "trackReEnrichSuccess": "Metadata re-enriched successfully",
+  "@trackReEnrichSuccess": {"description": "Snackbar after successful re-enrichment"},
+  "trackReEnrichFfmpegFailed": "FFmpeg metadata embed failed",
+  "@trackReEnrichFfmpegFailed": {"description": "Snackbar when FFmpeg embed fails for MP3/Opus"},
+  "trackSaveFailed": "Failed: {error}",
+  "@trackSaveFailed": {
+    "description": "Snackbar when save operation fails",
+    "placeholders": {
+      "error": {"type": "String"}
+    }
+  },
+
+  "trackConvertFormat": "Convert Format",
+  "@trackConvertFormat": {"description": "Menu item - convert audio format"},
+  "trackConvertFormatSubtitle": "Convert to MP3 or Opus",
+  "@trackConvertFormatSubtitle": {"description": "Subtitle for convert format menu item"},
+  "trackConvertTitle": "Convert Audio",
+  "@trackConvertTitle": {"description": "Title of convert bottom sheet"},
+  "trackConvertTargetFormat": "Target Format",
+  "@trackConvertTargetFormat": {"description": "Label for format selection"},
+  "trackConvertBitrate": "Bitrate",
+  "@trackConvertBitrate": {"description": "Label for bitrate selection"},
+  "trackConvertConfirmTitle": "Confirm Conversion",
+  "@trackConvertConfirmTitle": {"description": "Confirmation dialog title"},
+  "trackConvertConfirmMessage": "Convert from {sourceFormat} to {targetFormat} at {bitrate}?\n\nThe original file will be deleted after conversion.",
+  "@trackConvertConfirmMessage": {
+    "description": "Confirmation dialog message",
+    "placeholders": {
+      "sourceFormat": {"type": "String"},
+      "targetFormat": {"type": "String"},
+      "bitrate": {"type": "String"}
+    }
+  },
+  "trackConvertConverting": "Converting audio...",
+  "@trackConvertConverting": {"description": "Snackbar while converting"},
+  "trackConvertSuccess": "Converted to {format} successfully",
+  "@trackConvertSuccess": {
+    "description": "Snackbar after successful conversion",
+    "placeholders": {
+      "format": {"type": "String"}
+    }
+  },
+  "trackConvertFailed": "Conversion failed",
+  "@trackConvertFailed": {"description": "Snackbar when conversion fails"}
 }

lib/l10n/arb/app_es.arb

@@ -548,14 +548,6 @@
   "@aboutSupport": {
     "description": "Section for support/donation links"
   },
-  "aboutBuyMeCoffee": "Buy me a coffee",
-  "@aboutBuyMeCoffee": {
-    "description": "Donation link"
-  },
-  "aboutBuyMeCoffeeSubtitle": "Support development on Ko-fi",
-  "@aboutBuyMeCoffeeSubtitle": {
-    "description": "Subtitle for donation"
-  },
   "aboutApp": "App",
   "@aboutApp": {
     "description": "Section for app info"

lib/l10n/arb/app_pt.arb

@@ -548,14 +548,6 @@
   "@aboutSupport": {
     "description": "Section for support/donation links"
   },
-  "aboutBuyMeCoffee": "Buy me a coffee",
-  "@aboutBuyMeCoffee": {
-    "description": "Donation link"
-  },
-  "aboutBuyMeCoffeeSubtitle": "Support development on Ko-fi",
-  "@aboutBuyMeCoffeeSubtitle": {
-    "description": "Subtitle for donation"
-  },
   "aboutApp": "App",
   "@aboutApp": {
     "description": "Section for app info"

lib/l10n/arb/app_zh.arb

@@ -548,14 +548,6 @@
   "@aboutSupport": {
     "description": "Section for support/donation links"
   },
-  "aboutBuyMeCoffee": "Buy me a coffee",
-  "@aboutBuyMeCoffee": {
-    "description": "Donation link"
-  },
-  "aboutBuyMeCoffeeSubtitle": "Support development on Ko-fi",
-  "@aboutBuyMeCoffeeSubtitle": {
-    "description": "Subtitle for donation"
-  },
   "aboutApp": "App",
   "@aboutApp": {
     "description": "Section for app info"

lib/main.dart

@@ -1,4 +1,5 @@
 import 'dart:io';
+import 'package:device_info_plus/device_info_plus.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:path_provider/path_provider.dart';
@@ -11,52 +12,113 @@ import 'package:spotiflac_android/services/cover_cache_manager.dart';
 
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
-  
-  await CoverCacheManager.initialize();
-  debugPrint('CoverCacheManager initialized: ${CoverCacheManager.isInitialized}');
-  
-  await Future.wait([
-    NotificationService().initialize(),
-    ShareIntentService().initialize(),
-  ]);
-  
+  final runtimeProfile = await _resolveRuntimeProfile();
+  _configureImageCache(runtimeProfile);
+
   runApp(
     ProviderScope(
-      child: const _EagerInitialization(
-        child: SpotiFLACApp(),
+      child: _EagerInitialization(
+        child: SpotiFLACApp(
+          disableOverscrollEffects: runtimeProfile.disableOverscrollEffects,
+        ),
       ),
     ),
   );
 }
 
+Future<_RuntimeProfile> _resolveRuntimeProfile() async {
+  const defaults = _RuntimeProfile(
+    imageCacheMaximumSize: 240,
+    imageCacheMaximumSizeBytes: 60 << 20,
+    disableOverscrollEffects: false,
+  );
+
+  if (!Platform.isAndroid) return defaults;
+
+  try {
+    final androidInfo = await DeviceInfoPlugin().androidInfo;
+    final isArm32Only = androidInfo.supported64BitAbis.isEmpty;
+    final isLowRamDevice =
+        androidInfo.isLowRamDevice || androidInfo.physicalRamSize <= 2500;
+
+    if (!isArm32Only && !isLowRamDevice) {
+      return defaults;
+    }
+
+    return _RuntimeProfile(
+      imageCacheMaximumSize: 120,
+      imageCacheMaximumSizeBytes: 24 << 20,
+      disableOverscrollEffects: true,
+    );
+  } catch (e) {
+    debugPrint('Failed to resolve runtime profile: $e');
+    return defaults;
+  }
+}
+
+void _configureImageCache(_RuntimeProfile runtimeProfile) {
+  final imageCache = PaintingBinding.instance.imageCache;
+  // Keep memory cache bounded so cover-heavy pages don't retain too many
+  // full-resolution images simultaneously.
+  imageCache.maximumSize = runtimeProfile.imageCacheMaximumSize;
+  imageCache.maximumSizeBytes = runtimeProfile.imageCacheMaximumSizeBytes;
+}
+
+class _RuntimeProfile {
+  final int imageCacheMaximumSize;
+  final int imageCacheMaximumSizeBytes;
+  final bool disableOverscrollEffects;
+
+  const _RuntimeProfile({
+    required this.imageCacheMaximumSize,
+    required this.imageCacheMaximumSizeBytes,
+    required this.disableOverscrollEffects,
+  });
+}
+
 /// Widget to eagerly initialize providers that need to load data on startup
 class _EagerInitialization extends ConsumerStatefulWidget {
   const _EagerInitialization({required this.child});
   final Widget child;
 
   @override
-  ConsumerState<_EagerInitialization> createState() => _EagerInitializationState();
+  ConsumerState<_EagerInitialization> createState() =>
+      _EagerInitializationState();
 }
 
 class _EagerInitializationState extends ConsumerState<_EagerInitialization> {
   @override
   void initState() {
     super.initState();
+    _initializeAppServices();
     _initializeExtensions();
-    // Trigger history provider initialization without subscribing to updates.
     ref.read(downloadHistoryProvider);
   }
 
+  Future<void> _initializeAppServices() async {
+    try {
+      await CoverCacheManager.initialize();
+      await Future.wait([
+        NotificationService().initialize(),
+        ShareIntentService().initialize(),
+      ]);
+    } catch (e) {
+      debugPrint('Failed to initialize app services: $e');
+    }
+  }
+
   Future<void> _initializeExtensions() async {
     try {
       final appDir = await getApplicationDocumentsDirectory();
       final extensionsDir = '${appDir.path}/extensions';
       final dataDir = '${appDir.path}/extension_data';
-      
+
       await Directory(extensionsDir).create(recursive: true);
       await Directory(dataDir).create(recursive: true);
-      
-      await ref.read(extensionProvider.notifier).initialize(extensionsDir, dataDir);
+
+      await ref
+          .read(extensionProvider.notifier)
+          .initialize(extensionsDir, dataDir);
     } catch (e) {
       debugPrint('Failed to initialize extensions: $e');
     }

lib/models/download_item.dart

@@ -28,6 +28,7 @@ class DownloadItem {
   final DownloadStatus status;
   final double progress;
   final double speedMBps;
+  final int bytesReceived; // Bytes downloaded so far (for unknown size downloads)
   final String? filePath;
   final String? error;
   final DownloadErrorType? errorType;
@@ -41,6 +42,7 @@ class DownloadItem {
     this.status = DownloadStatus.queued,
     this.progress = 0.0,
     this.speedMBps = 0.0,
+    this.bytesReceived = 0,
     this.filePath,
     this.error,
     this.errorType,
@@ -55,6 +57,7 @@ class DownloadItem {
     DownloadStatus? status,
     double? progress,
     double? speedMBps,
+    int? bytesReceived,
     String? filePath,
     String? error,
     DownloadErrorType? errorType,
@@ -68,6 +71,7 @@ class DownloadItem {
       status: status ?? this.status,
       progress: progress ?? this.progress,
       speedMBps: speedMBps ?? this.speedMBps,
+      bytesReceived: bytesReceived ?? this.bytesReceived,
       filePath: filePath ?? this.filePath,
       error: error ?? this.error,
       errorType: errorType ?? this.errorType,