fix: revert material_color_utilities to ^0.11.1 (pinned by Flutter SDK)

- Add flutter_localizations and intl to pubspec_ios.yaml

- Add generate: true flag for l10n code generation

- Add CFBundleLocalizations to Info.plist with all supported languages

- Update http to ^1.6.0 and material_color_utilities to ^0.13.0

- Update file_picker to ^10.3.8

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -16,7 +16,7 @@ body:
       options:
         - label: I have searched existing issues and this bug hasn't been reported yet
           required: true
-        - label: I am using the latest version of SpotiFLAC
+        - label: I am using the latest version of SpotiFLAC (Stable Version)
           required: true
 
   - type: textarea

.github/ISSUE_TEMPLATE/config.yml

@@ -3,3 +3,6 @@ contact_links:
   - name: README
     url: https://github.com/zarzet/SpotiFLAC-Mobile#readme
     about: Check the README for setup instructions and FAQ
+  - name: Extension Development Guide
+    url: https://zarz.moe/docs
+    about: Documentation for building SpotiFLAC extensions

.github/ISSUE_TEMPLATE/download_issue.yml

@@ -16,7 +16,7 @@ body:
       options:
         - label: I have tried downloading with a different service (Tidal/Qobuz/Amazon)
           required: true
-        - label: I am using the latest version of SpotiFLAC
+        - label: I am using the latest version of SpotiFLAC (Stable Version)
           required: true
 
   - type: dropdown

.github/ISSUE_TEMPLATE/extension_feature_request.yml

@@ -0,0 +1,117 @@
+name: Extension API Feature Request
+description: Request new API features or capabilities for extension development
+title: "[Extension API]: "
+labels: ["enhancement", "extension-api"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thanks for helping improve the SpotiFLAC Extension API! 
+        This form is for extension developers who need new features or capabilities that don't exist yet.
+
+  - type: checkboxes
+    id: checklist
+    attributes:
+      label: Checklist
+      description: Please confirm the following before submitting
+      options:
+        - label: I have read the [Extension Development Guide](https://github.com/zarzet/SpotiFLAC-Mobile/blob/main/docs/EXTENSION_DEVELOPMENT.md)
+          required: true
+        - label: I have searched existing issues and this API feature hasn't been requested yet
+          required: true
+
+  - type: textarea
+    id: extension_goal
+    attributes:
+      label: What are you trying to build?
+      description: Describe the extension or feature you're developing
+      placeholder: "I'm building an extension that downloads from [service name] / provides metadata from [source]..."
+    validations:
+      required: true
+
+  - type: textarea
+    id: current_limitation
+    attributes:
+      label: Current API Limitation
+      description: What's missing or limiting in the current extension API?
+      placeholder: |
+        The current API doesn't support:
+        - [missing feature 1]
+        - [missing feature 2]
+        
+        This prevents me from...
+    validations:
+      required: true
+
+  - type: textarea
+    id: proposed_api
+    attributes:
+      label: Proposed API / Feature
+      description: Describe the API or feature you'd like to see added
+      placeholder: |
+        I would like to have:
+        - A new function `api.newFeature()` that does X
+        - A new manifest field `newOption` that enables Y
+        - Access to Z capability...
+    validations:
+      required: true
+
+  - type: textarea
+    id: use_case
+    attributes:
+      label: Use Case Example
+      description: Provide a code example of how you would use this feature
+      placeholder: |
+        ```javascript
+        // Example usage in extension code
+        function download(request, progressCallback) {
+          const result = api.proposedFeature(params);
+          // ...
+        }
+        ```
+    validations:
+      required: false
+
+  - type: dropdown
+    id: api_category
+    attributes:
+      label: API Category
+      description: What category does this feature fall under?
+      options:
+        - HTTP/Network API
+        - File System API
+        - Storage API
+        - FFmpeg/Audio Processing
+        - Manifest Options
+        - Runtime Functions
+        - UI Integration
+        - Authentication
+        - Other
+    validations:
+      required: true
+
+  - type: dropdown
+    id: priority
+    attributes:
+      label: How critical is this for your extension?
+      options:
+        - Blocker - Cannot build my extension without this
+        - High - Major functionality depends on this
+        - Medium - Would significantly improve my extension
+        - Low - Nice to have
+    validations:
+      required: true
+
+  - type: textarea
+    id: workaround
+    attributes:
+      label: Current Workaround
+      description: Are you using any workaround currently? If so, describe it.
+      placeholder: "Currently I'm working around this by..."
+
+  - type: textarea
+    id: additional
+    attributes:
+      label: Additional Context
+      description: Add any other context, links to similar APIs, or examples from other platforms
+      placeholder: "Similar feature in other platforms: ..."

.github/workflows/release.yml

@@ -345,6 +345,8 @@ jobs:
             CHANGELOG="See CHANGELOG.md for details."
           else
             echo "Found changelog content"
+            # Remove trailing --- separator if present (CHANGELOG uses --- between versions)
+            CHANGELOG=$(echo "$CHANGELOG" | sed '/^---$/d')
           fi
 
           # Save to file for multiline support

.gitignore

@@ -13,6 +13,9 @@ Thumbs.db
 # Reference folder (development only)
 referensi/
 
+# Documentation (development only, published separately)
+docs/
+
 # Old spotiflac_android folder (moved to root)
 spotiflac_android/
 
@@ -50,3 +53,20 @@ ios/.symlinks/
 ios/Flutter/Flutter.framework/
 ios/Flutter/Flutter.podspec
 android/app/libs/gobackend-sources.jar
+
+# Extension folder
+extension/
+
+# Agent instructions
+AGENTS.md
+
+# Temp/misc
+nul
+
+# Log files
+*.log
+hs_err_*.log
+flutter_*.log
+
+# Development tools
+tool/

CHANGELOG.md

@@ -1,5 +1,769 @@
 # Changelog
 
+## [3.1.0] - 2026-01-19
+
+### Added
+
+- **Recent Access History**: Quick access to recently visited content when tapping the search bar
+  - Shows recently visited artists, albums, playlists, and downloaded tracks
+  - Merged view combining navigation history and download history
+  - Tap to quickly navigate back to previously accessed content
+  - X button to remove individual items from history
+  - "Clear All" button to clear entire history
+  - Persists across app restarts (stored in SharedPreferences)
+  - Max 20 items stored, sorted by most recent
+  - Multi-language support (Artist/Album/Song/Playlist labels localized)
+
+- **Artist Screen Redesign**
+  - Full-width header image (380px) with gradient overlay
+  - Artist name displayed at bottom of header with text shadow
+  - Monthly listeners count display (formatted with compact notation)
+  - "Popular" section showing top 5 tracks with download status indicators
+  - Dynamic download button states (queued, downloading, completed)
+  - Header image and top tracks fetched from extension metadata
+  - Image alignment set to top-center to show faces properly
+
+- **Extension Store Update Badge**: Badge indicator on Store tab icon showing number of available updates
+  - Users can see extension updates are available without opening Store tab
+  - Badge shows count of extensions with updates
+
+- **Extension Compatibility Warning**: Warning badge for extensions requiring newer app version
+  - Extensions with `minAppVersion` higher than current app show warning label
+  - Label displays "Requires vX.X.X+" to encourage users to upgrade
+  - Users can still install the extension (not blocked)
+
+- **Year in Album Folder Name** ([#50](https://github.com/zarzet/SpotiFLAC-Mobile/issues/50)): New album folder structure options with release year
+
+  - `Artist / [Year] Album`: Albums/Coldplay/[2005] X&Y/
+  - `[Year] Album Only`: Albums/[2005] X&Y/
+  - Year extracted from release date metadata
+  - Matches desktop SpotiFLAC folder structure
+
+- **Extension Album/Playlist/Artist Support**: Extensions can now return albums, playlists, and artists in search results
+
+  - Search results now properly separated into Albums, Playlists, Artists, and Songs sections
+  - Albums, playlists, and artists show chevron icon (navigate to detail) instead of download button
+  - Tap album/playlist to view track list and download
+  - Tap artist to view their albums/discography
+  - New `getAlbum()`, `getPlaylist()`, and `getArtist()` extension functions
+  - New `ExtensionAlbumScreen`, `ExtensionPlaylistScreen`, and `ExtensionArtistScreen` for fetching content from extensions
+  - YouTube Music extension updated with album/playlist/artist support
+
+- **Odesli (song.link) Integration for YouTube Music Extension**
+  - New `enrichTrack()` function to fetch ISRC and external service links
+  - Uses Odesli API to convert YouTube Music tracks to Deezer/Tidal/Qobuz
+  - Enables built-in service fallback for high-quality audio downloads
+  - Extension version updated to 1.4.0 with `api.song.link` and `odesli.io` network permissions
+- **Download Cancel**: Canceling a download now stops in-flight built-in provider downloads (Tidal/Qobuz/Amazon) and clears backend progress tracking.
+
+### Changed
+
+- **Search Bar Behavior**: Tapping search bar now immediately moves it to top position
+  - Logo and subtitle hide when search bar is focused
+  - Recent access history appears in the content area below
+  - More space for recent items, not blocked by keyboard
+
+### Fixed
+
+- Fixed search source chips still referencing removed badge props.
+- Fixed extension artist album metadata to preserve provider IDs and cover URLs for correct navigation.
+- Fixed extension playlist fetch to populate provider IDs and reject disabled extensions.
+- Fixed extension collection screens calling setState after dispose during async loads.
+- Fixed URL handler responses to include provider IDs for extension albums and artists.
+- Fixed YTMusic extension not extracting album name and duration from search results.
+  - Album name is now extracted from flexColumns/subtitle when linked to album browseId.
+  - Duration is now extracted from fixedColumns/flexColumns in addition to existing sources.
+- Fixed "Separate Singles" setting not working ([#54](https://github.com/zarzet/SpotiFLAC-Mobile/issues/54)) - singles were going to Albums folder.
+  - Root cause: `albumType` was not being extracted from Deezer API during metadata enrichment.
+  - Deezer track responses now correctly include `album_type` (single/ep/album/compilation).
+  - Track creation now preserves `albumType` and `source` fields throughout download flow.
+- Fixed PageView overscroll at edges (BouncingScrollPhysics → ClampingScrollPhysics)
+- Fixed settings item highlight on swipe (highlightColor: Colors.transparent)
+- Fixed extension duplicate load error (skip silently instead of throwing error)
+- Fixed keyboard appearing when swiping between tabs (unfocus on page change)
+- Removed "Free"/"API Key" badges from search source selector
+- Fixed cancel action briefly resuming downloads in the queue UI after ~1 second.
+- Fixed cancelled downloads being marked as failed when the backend returns after cancellation.
+- Fixed cancel triggering provider fallback (cancel now stops the download flow immediately).
+- Fixed stale ISRC cache returning deleted files after cancel.
+- Fixed search results mixing extension and built-in artists when using default provider.
+- Fixed audio files opening with non-music apps by passing audio MIME type on open.
+- Fixed album artist showing null/blank by normalizing empty metadata and using artist fallback for tags.
+- Fixed `use_build_context_synchronously` lint warnings in `home_tab.dart`
+- Fixed `unnecessary_underscores` lint warnings in error widget callbacks
+- Fixed duplicate artist entries in recent history (recording now only happens in screen's initState)
+- **Go Backend: Missing `item_type` and `album_type` fields**
+  - Added `ItemType` and `AlbumType` fields to `ExtTrackMetadata` struct
+  - Fixed `CustomSearchWithExtensionJSON` - now includes `item_type` and `album_type` in response
+  - Fixed `HandleURLWithExtensionJSON` - now includes `item_type` and `album_type` for tracks
+  - Fixed `GetAlbumWithExtensionJSON` - now includes `item_type` and `album_type` for album tracks
+  - Fixed `GetPlaylistWithExtensionJSON` - now includes `item_type` and `album_type` for playlist tracks
+- **Album/Playlist Track Thumbnails**: Tracks inside albums/playlists now use album/playlist cover as fallback when no individual cover exists
+- **YouTube Music Extension getArtist**: Fixed `getArtist()` function not being registered in extension, causing artist pages to fail with "returned null" error
+- **Recent Access UI**: Fixed recent access list disappearing when keyboard is dismissed - now stays visible until user presses Back button
+- **Extension Artist Top Tracks**: Fixed top tracks not appearing when opening artist from extension search results
+  - YT Music extension `getArtist()` now returns `top_tracks` array with up to 10 popular songs
+  - Go backend `GetArtistWithExtensionJSON` now forwards `top_tracks`, `header_image`, and `listeners` to Flutter
+  - `ExtensionArtistScreen` now parses and passes top tracks to `ArtistScreen`
+  - `ArtistScreen` with `extensionId` skips Spotify/Deezer fetch, uses extension data only (fixes "Rate Limited" errors)
+- **Search Bar Unfocus**: Fixed search bar not unfocusing when tapping outside - now properly dismisses keyboard and unfocus when tapping anywhere outside the search field
+- **Keyboard Appearing on Settings Navigation**: Fixed keyboard randomly appearing when returning from Settings sub-pages (e.g., Appearance) - now uses `FocusManager.instance.primaryFocus?.unfocus()` for more aggressive unfocus
+- **Recent Access Artist Navigation**: Fixed opening artist from recent access using wrong screen - now correctly uses `ExtensionArtistScreen` for extension artists (YT Music, Spotify Web) instead of trying to fetch from Spotify API
+
+### Extensions
+
+- **YouTube Music Extension**: Updated to v1.5.0
+  - `getArtist()` now returns `top_tracks` array with popular songs
+  - Added `header_image` and `listeners` to artist response
+- **Spotify Web Extension**: Updated to v1.6.0
+
+### Localization
+
+- **Multi-Language Support**: App now supports multiple languages with community contributions via Crowdin
+  - Available languages: English, Indonesian (Bahasa Indonesia)
+  - More languages coming soon with community translations
+  - Contribute translations at [Crowdin](https://crowdin.com/project/spotiflac-mobile)
+- Added new localization strings for recent access types:
+  - `recentTypeArtist` - "Artist" / "Artis"
+  - `recentTypeAlbum` - "Album" / "Album"
+  - `recentTypeSong` - "Song" / "Lagu"
+  - `recentTypePlaylist` - "Playlist" / "Playlist"
+  - `recentPlaylistInfo` - "Playlist: {name}"
+  - `errorGeneric` - "Error: {message}"
+
+---
+
+## [3.0.0] - 2026-01-14
+
+### Extension System (Major Feature)
+
+SpotiFLAC 3.0 introduces a powerful extension system that allows third-party integrations for metadata, downloads, and more.
+
+#### Extension Store
+
+- Browse and install extensions directly from the app
+- New "Store" tab in bottom navigation
+- Browse by category: Metadata, Download, Utility, Lyrics, Integration
+- Search extensions by name, description, or tags
+- One-tap install, update, and uninstall
+- Offline cache for browsing without internet
+
+#### Spotify Web Extension
+
+- Available in Extension Store - install and enable in Settings > Extensions
+- Metadata provider using Spotify's internal web player API
+- Download tracks from Daily Mix, Discover Weekly, and other personalized playlists
+- Useful when official Spotify API is rate-limited or unavailable
+
+#### Extension Capabilities
+
+- **Custom Search Providers**
+- **Custom URL Handlers**
+- **Custom Thumbnail Ratios**: Square (1:1), Wide (16:9), Portrait (2:3)
+- **Post-Processing Hooks**: Extensions can process downloaded files
+- **Quality Options**: Extensions can define custom quality settings
+
+#### Extension APIs
+
+- Full HTTP support: GET, POST, PUT, DELETE, PATCH
+- Persistent cookie jar per extension
+- Browser-like polyfills: `fetch()`, `atob()`/`btoa()`, `TextEncoder`/`TextDecoder`, `URL`/`URLSearchParams`
+- Storage API for persistent data
+- File API for file operations
+- HMAC-SHA1 utility for cryptographic operations
+
+#### Security
+
+- Sandboxed JavaScript runtime (goja)
+- Permission-based access control
+- Network domain whitelisting
+- Improved credential encryption with per-installation random salt
+
+### Added
+
+- **Album Folder Structure Setting**: Option to remove artist folder from album path
+
+  - `Artist / Album` (default): `Albums/Artist Name/Album Name/`
+  - `Album Only`: `Albums/Album Name/`
+
+- **Separate Singles Folder**: Organize downloads into Albums/ and Singles/ folders
+
+  - Based on `album_type` from Spotify/Deezer metadata
+  - Toggle in Settings > Download > Separate Singles Folder
+
+- **Year in Album Folder Name**: New album folder structure options with release year
+
+  - `Artist / [Year] Album`: Albums/Coldplay/[2005] X&Y/
+  - `[Year] Album Only`: Albums/[2005] X&Y/
+  - Year extracted from release date metadata
+  - Matches desktop SpotiFLAC folder structure
+
+- **Parallel API Calls**: Download URL fetching now uses parallel requests
+  - Tidal: All 8 APIs requested simultaneously, first success wins
+  - Qobuz: Both APIs requested simultaneously, first success wins
+  - Significantly reduces download URL fetch time
+
+### UI/UX Improvements
+
+- **Swipeable History Filters**: History tab now supports swipe gestures between All, Albums, and Singles filters
+
+  - Swipe left/right to switch between filter tabs
+  - Filter chips sync with swipe position
+  - Smooth edge-to-edge transition: swipe past Singles to go to Store, swipe past All to go to Home
+  - Natural gesture feel - drag connects to parent navigation
+
+  - **Improved File Open Intent**: Play button in History now correctly opens music players only
+  - Added proper MIME type (`audio/flac`, `audio/mpeg`, etc.) when opening downloaded files
+  - Prevents system from showing unrelated apps in the "Open with" dialog
+
+### Fixed
+
+- **Fixed Tab Edge Overscroll**: Home and Settings tabs now stop at edges instead of bouncing into empty space
+
+- **Fixed Extension Duplicate Load Error**: Extension loading now silently skips already-loaded extensions instead of throwing error
+
+- **Fixed Settings Item Highlight on Swipe**: Settings items no longer highlight when swiping at page edge
+
+- **Fixed Keyboard Appearing on Tab Switch**: Keyboard now auto-dismisses when swiping between tabs
+
+- **Removed Search Source Badges**: Removed "Free" and "API Key" labels from Deezer/Spotify selector in Options
+
+- **Back Gesture Freeze on Android 13+**: Fixed app freeze when using back gesture in settings
+
+  - Added `PopScope` with `canPop: true` to all settings pages
+  - Changed navigation to use `PageRouteBuilder` with proper slide transition
+
+- **Bottom Overflow in Folder Organization Dialog**: Fixed overflow in portrait and landscape mode
+
+  - Made dialog scrollable with max height constraint
+
+- **Japanese Artist Name Order**: Fixed artist mismatch for Japanese names
+
+  - "Sawano Hiroyuki" vs "Hiroyuki Sawano" now correctly matches
+
+- **Multi-Artist Matching**: Fixed artist mismatch for collaboration tracks
+
+  - "RADWIMPS feat. Toko Miura" now matches when service only shows "Toko Miura"
+
+- **Max Resolution Cover Download**: Fixed cover not upgrading to max resolution on mobile
+
+  - Mobile now correctly upgrades 300x300 → 640x640 → max resolution (~2000x2000)
+
+- **EXISTS: Prefix in File Path**: Fixed "File not found" error in metadata screen
+
+  - Duplicate detection prefix now stripped before saving to history
+
+- **Extension Search Result Parsing**: Fixed "cannot unmarshal array" error
+
+  - Go backend now handles both array and object formats from extensions
+
+- **Store Tab Unmount Crash**: Fixed "Using ref when widget is unmounted" error
+
+- **Duplicate History Entries**: Fixed duplicate entries when re-downloading same track
+
+  - Detects existing entries by Spotify ID, Deezer ID, or ISRC
+
+- **Permission Error Message**: Fixed download showing "Song not found" when actually permission error
+
+  - Now shows proper message: "Cannot write to folder, check storage permission"
+
+- **Android 13+ Storage Permission**: Fixed storage permission not working on Android 13+
+  - Now requests both `MANAGE_EXTERNAL_STORAGE` and `READ_MEDIA_AUDIO`
+
+### Changed
+
+- **Extension Manifest**: New `file` permission required for file operations
+  ```json
+  "permissions": {
+    "network": ["api.example.com"],
+    "storage": true,
+    "file": true
+  }
+  ```
+
+### Technical
+
+- Go backend: Simplified parallel download result handling in Tidal/Qobuz
+- Go backend: Removed unused functions and fixed bit shifting warnings
+- Release workflow: Fixed duplicate `---` separator in release notes
+
+---
+
+## [3.0.0-beta.2] - 2026-01-13
+
+### Added
+
+- **Album Folder Structure Setting**: Option to remove artist folder from album path
+  - New setting in Download Settings when "Separate Singles Folder" is enabled
+  - `Artist / Album` (default): `Albums/Artist Name/Album Name/`
+  - `Album Only`: `Albums/Album Name/`
+  - Requested by user who prefers flat album organization
+
+### Fixed
+
+- **Back Gesture Freeze on OnePlus/Android 13+**: Fixed app freeze when using back gesture in settings
+
+  - Added `PopScope` with `canPop: true` to all settings pages
+  - Changed navigation to use `PageRouteBuilder` with proper slide transition
+  - Fixes predictive back gesture conflict on devices with gesture navigation
+  - Affected pages: Download, Appearance, Options, Extensions, About, Logs, Extension Detail
+
+- **Extension Search Result Parsing**: Fixed "cannot unmarshal array into Go value" error
+
+  - Go backend now handles both array and object formats from extensions
+  - Extensions returning `[{track}, {track}]` now work correctly
+  - Extensions returning `{tracks: [...], total: N}` still work as before
+
+- **Max Resolution Cover Download**: Fixed cover not upgrading to max resolution on mobile
+
+  - Added missing `spotifySize300` constant (300x300 size code)
+  - Mobile now correctly upgrades 300x300 → 640x640 → max resolution (~2000x2000)
+  - Added `_upgradeToMaxQualityCover()` helper in Flutter for M4A conversion path
+  - Go backend `cover.go` now directly replaces URL without HEAD verification
+
+- **Extension Search Provider Reset**: Fixed search provider not resetting to default when disabled
+
+  - `copyWith` in `AppSettings` couldn't set `searchProvider` to `null`
+  - Added `clearSearchProvider` boolean parameter to properly clear the value
+  - Settings menu now correctly switches back to default provider
+
+- **Extension Disabled Search Fallback**: Fixed error when extension is disabled but still called
+
+  - `_performSearch` now checks if extension is still enabled before calling custom search
+  - Automatically falls back to Deezer/Spotify search if extension was disabled
+  - Clears `searchProvider` setting if extension no longer available
+
+- **Store Tab Unmount Crash**: Fixed "Using ref when widget is unmounted" error
+
+  - Added `mounted` check after async operation in `_initialize()`
+  - Prevents crash when navigating away from Store tab during initialization
+
+- **EXISTS: Prefix in File Path**: Fixed "File not found" error in metadata screen after download
+
+  - Duplicate detection was adding `EXISTS:` prefix to file paths
+  - Prefix now stripped before saving to download history
+  - Legacy history items with prefix are handled gracefully
+
+- **History Error Badge**: Fixed error badge showing on history items even when file exists
+
+  - `queue_tab.dart` now strips `EXISTS:` prefix before checking file existence
+  - File open and delete operations also use cleaned path
+
+- **Extension Artist URL Handler**: Fixed artist pages showing "0 releases" from extensions
+
+  - Extension `fetchArtist` now returns correct format: `{ type: "artist", artist: { albums } }`
+  - Go backend `HandleURLWithExtensionJSON` now includes albums in artist response
+  - Added `AlbumType` field to `ExtAlbumMetadata` struct
+
+- **Extension Artist Name in Logs**: Fixed empty artist name in extension track logs
+
+  - Now uses `firstArtist` + `otherArtists` instead of deprecated `artists.items`
+  - Logs correctly show "Fetched track: {title} by {artist}"
+
+- **Japanese Artist Name Order**: Fixed artist mismatch for Japanese names with different order
+
+  - "Sawano Hiroyuki" vs "Hiroyuki Sawano" now correctly matches
+  - Added `sameWordsUnordered` check to both Tidal and Qobuz artist matching
+  - Handles Japanese name order (family name first) vs Western name order (given name first)
+
+- **Multi-Artist Matching**: Fixed artist mismatch for collaboration tracks
+
+  - "RADWIMPS feat. Toko Miura" now matches when Qobuz/Tidal only shows "Toko Miura"
+  - Split artists by separators (`, `, `feat.`, `ft.`, `&`, `and`, `x`)
+  - Match if ANY expected artist matches ANY found artist
+
+- **Cover Download Logging**: Improved cover download logs for debugging
+  - Shows original URL, upgrade steps, and final URL
+  - Displays estimated resolution based on file size
+  - Logs now appear in Settings > Logs via GoLog
+
+---
+
+## [3.0.0-beta.1] - 2026-01-13
+
+### Security
+
+- Improved extension sandbox security
+- Improved credential encryption with per-installation random salt
+
+### Changed
+
+- **Extension Manifest**: New `file` permission required for file operations
+  ```json
+  "permissions": {
+    "network": ["api.example.com"],
+    "storage": true,
+    "file": true
+  }
+  ```
+  Extensions that need to download files must declare `"file": true` in manifest.
+
+### Fixed
+
+- Extension packages now preserve directory structure (subdirectories supported)
+- Back gesture freeze in settings pages on Android gesture navigation
+
+---
+
+## [3.0.0-alpha.4] - 2026-01-12
+
+### Added
+
+- **Extension Store**: Browse and install extensions directly from the app
+
+  - New "Store" tab in bottom navigation
+  - Browse extensions by category (Metadata, Download, Utility, Lyrics, Integration)
+  - Search extensions by name, description, or tags
+  - One-tap install and update
+  - Offline cache for browsing without internet
+  - Extensions hosted at github.com/zarzet/SpotiFLAC-Extension
+
+- **Custom URL Handler for Extensions**: Extensions can now register custom URL patterns
+
+  - Handle URLs from YouTube Music, SoundCloud, Bandcamp, etc.
+  - Manifest config: `urlHandler: { enabled: true, patterns: ["music.youtube.com"] }`
+  - Implement `handleUrl(url)` function in extension to parse and return track metadata
+  - SpotiFLAC automatically routes matching URLs to the appropriate extension
+  - Supports share intents and paste from clipboard
+
+- **Artist URL Handler Support**: Extensions can now return artist data from URL handlers
+
+  - Added `type: "artist"` handling in track_provider.dart
+  - Navigate to artist screen with albums list from extension
+
+- **HMAC-SHA1 Utility**: New `utils.hmacSHA1(key, message)` function for extensions
+  - Enables TOTP generation and other cryptographic operations
+  - Returns byte array for flexible use
+
+### Fixed
+
+- **Extension Store Refresh**: Store tab now properly refreshes after uninstalling an extension
+  - "Installed" badge correctly updates to "Install" button
+
+### Documentation
+
+- Updated `docs/EXTENSION_DEVELOPMENT.md`:
+  - Added Custom URL Handler section with examples
+  - Added `handleUrl` function documentation
+  - Added URL pattern examples for YouTube, SoundCloud, Bandcamp
+  - Added `utils.hmacSHA1` documentation with TOTP example
+
+### Extensions
+
+- **Spotify Web Extension** (example): New extension for Spotify metadata via web API
+  - Supports personalized playlists (Daily Mix, Discover Weekly, Release Radar, etc.)
+  - Search, album, playlist, track, and artist fetching
+  - Available in Extension Store (3.0.0-alpha.4)
+
+---
+
+## [3.0.0-alpha.3] - 2026-01-12
+
+### Added
+
+- **Separate Singles Folder**: Option to organize downloads into Albums/ and Singles/ folders
+  - Based on `album_type` from Spotify/Deezer metadata
+  - Toggle in Settings > Download > Separate Singles Folder
+  - Singles saved to `{output}/Singles/`, albums to `{output}/Albums/`
+- **Browser-like Polyfills**: New global APIs for easier library porting
+  - `fetch()` - Browser-compatible HTTP API with `json()`, `text()`, `arrayBuffer()` methods
+  - `atob()` / `btoa()` - Global Base64 encoding/decoding
+  - `TextEncoder` / `TextDecoder` - UTF-8 text encoding classes
+  - `URL` / `URLSearchParams` - URL parsing and manipulation classes
+  - Makes porting browser libraries (like `youtubei.js`) much easier
+
+### Performance
+
+- **Parallel API Calls**: Download URL fetching now uses parallel requests
+  - Tidal: All 8 APIs requested simultaneously, first success wins
+  - Qobuz: Both APIs requested simultaneously, first success wins
+  - Significantly reduces download URL fetch time
+
+### Fixed
+
+- **Duplicate History Entries**: Fixed duplicate entries when re-downloading same track
+  - Detects existing entries by Spotify ID, Deezer ID, or ISRC
+  - Replaces existing entry and moves to top of list
+  - Auto-deduplicates existing history on app load
+- **Extension Search Fallback**: Fixed error when extension is disabled but still called for search
+  - Now checks if extension is still enabled before calling custom search
+  - Auto-resets search provider to default if extension was disabled
+- **Permission Error Message**: Fixed download showing "Song not found" when actually a permission error
+  - Now shows proper message: "Cannot write to folder, check storage permission"
+  - Added `permission` error type detection in backend
+- **Android 13+ Storage Permission**: Fixed storage permission not working on Android 13+
+  - Android 13+ now requests both `MANAGE_EXTERNAL_STORAGE` and `READ_MEDIA_AUDIO`
+  - `MANAGE_EXTERNAL_STORAGE` opens Settings (system-level, persists across app data clear)
+  - `READ_MEDIA_AUDIO` shows dialog (app-level, resets on app data clear)
+  - Proper permission check before showing "granted" status
+
+---
+
+## [3.0.0-alpha.2] - 2026-01-12
+
+### Added
+
+- **Full HTTP Method Support**: New shortcut methods for all common HTTP verbs
+  - `http.put(url, body, headers)` - PUT requests
+  - `http.delete(url, headers)` - DELETE requests
+  - `http.patch(url, body, headers)` - PATCH requests
+  - `http.clearCookies()` - Clear all cookies for the extension
+- **Persistent Cookie Jar**: Each extension now has its own cookie jar
+  - Cookies automatically stored from `Set-Cookie` headers
+  - Cookies automatically sent with subsequent requests to same domain
+  - Useful for APIs requiring session cookies (YouTube, etc.)
+- **Multi-Value Header Support**: Response headers now return arrays for multi-value headers
+  - `Set-Cookie` and other headers with multiple values returned as arrays
+  - Single-value headers still returned as strings for convenience
+- **Generic HTTP Request Method**: New `http.request()` for full HTTP control
+  - Supports all HTTP methods (GET, POST, PUT, DELETE, PATCH, etc.)
+  - Single options object for cleaner API: `http.request(url, { method, body, headers })`
+- **Response Helper Properties**: HTTP responses now include convenience properties
+  - `response.ok` - true if status code is 2xx
+  - `response.status` - alias for `statusCode`
+
+### Fixed
+
+- **User-Agent Header Respect**: Custom `User-Agent` headers are now respected
+  - Previously, extension-provided User-Agent was overwritten
+  - Now only sets default User-Agent if extension doesn't provide one
+- **HTTP POST Body Auto-Stringify**: `http.post()` now automatically stringifies objects to JSON
+  - Previously, passing an object as body resulted in `[object Object]`
+  - Now objects and arrays are automatically JSON.stringify'd
+  - String bodies still work as before (no double-encoding)
+
+### Documentation
+
+- Updated `docs/EXTENSION_DEVELOPMENT.md`:
+  - Added complete HTTP API documentation with all methods
+  - Added Cookie Jar documentation
+  - Added `http.put()`, `http.delete()`, `http.patch()`, `http.clearCookies()` docs
+  - Added YouTube Music / Innertube API example with custom User-Agent
+  - Added common domain lists for YouTube, SoundCloud, Bandcamp
+  - Improved HTTP API documentation with response properties
+
+---
+
+## [3.0.0-alpha.1] - 2026-01-11
+
+#### Extension System
+
+- **Custom Search Providers**: Extensions can now provide custom search functionality
+  - YouTube, SoundCloud, and other platforms via extensions
+  - Custom search placeholder text per extension
+  - Configurable thumbnail aspect ratios (square, wide, portrait)
+- **Extension Upgrade System**: Upgrade extensions without losing data
+  - Preserves extension settings and cached data during upgrades
+  - Version comparison prevents downgrades
+  - Auto-detects upgrades when installing same extension
+- **Custom Thumbnail Ratios**: Extensions can specify thumbnail display format
+  - `"square"` (1:1) - Album art style (default)
+  - `"wide"` (16:9) - YouTube/video style
+  - `"portrait"` (2:3) - Poster style
+  - Custom width/height override available
+
+### Added
+
+- **Track Source Tracking**: Tracks now remember which extension provided them
+  - `Track.source` field stores extension ID
+  - `TrackState.searchExtensionId` for current search context
+  - Enables extension-specific UI customization
+- **Extension Upgrade API**: New methods for extension management
+  - `upgradeExtension(filePath)` - Upgrade existing extension
+  - `checkExtensionUpgrade(filePath)` - Check if file is an upgrade
+  - `RemoveExtensionByID` - Remove extension by ID
+- **iOS Extension Support**: Added missing iOS method handlers
+  - `upgradeExtension` - Upgrade extension from file
+  - `checkExtensionUpgrade` - Check upgrade compatibility
+- **Extension Documentation**: Comprehensive extension development guide
+  - Thumbnail ratio customization documentation
+  - Extension upgrade workflow documentation
+  - New troubleshooting entries for common issues
+
+### Changed
+
+- **Version Bump**: 2.2.7 → 3.0.0-alpha.1 (major version for extension system)
+- **Build Number**: 49 → 50
+- **Extension Manager**: Improved upgrade detection in `LoadExtensionFromFile`
+  - Auto-detects if installing same extension with higher version
+  - Calls `UpgradeExtension` automatically for seamless upgrades
+
+### Fixed
+
+- **Extension `registerExtension`**: Fixed global `extension` variable not being set
+  - Extensions can now access their own functions via `extension.functionName()`
+  - Required for `customSearch` and other provider functions
+- **Custom Search Empty Results**: Fixed error when extension returns null
+  - Now returns empty array instead of error
+  - Prevents crash when no results found
+- **Mutex Crash on Upgrade**: Fixed "Unlock of unlocked RWMutex" crash
+  - Removed `defer m.mu.Unlock()` when manual unlock is used
+  - Proper lock handling in upgrade flow
+- **Duplicate Error Messages**: Fixed extension install errors showing twice
+  - Added `clearError()` method to extension provider
+  - Improved PlatformException parsing to remove "null, null" artifacts
+- **Extension Images Field**: Fixed thumbnails not showing in search results
+  - Added `Images` field to `ExtTrackMetadata` struct
+  - Renamed `GetCoverURL` to `ResolvedCoverURL` (gomobile conflict)
+
+### Technical
+
+- **Go Backend Changes**:
+  - `go_backend/extension_manager.go`: Added `compareVersions()`, `UpgradeExtension()`, `CheckExtensionUpgradeJSON()`
+  - `go_backend/extension_providers.go`: Added `Images` field, `ResolvedCoverURL()` method
+  - `go_backend/extension_manifest.go`: Added `ThumbnailRatio`, `ThumbnailWidth`, `ThumbnailHeight` to `SearchBehaviorConfig`
+  - `go_backend/exports.go`: Added `RemoveExtensionByID`, `UpgradeExtensionFromPath`, `CheckExtensionUpgradeFromPath`
+- **Flutter Changes**:
+  - `lib/models/track.dart`: Added `source` field
+  - `lib/models/track.g.dart`: Updated for `source` field
+  - `lib/providers/track_provider.dart`: Added `searchExtensionId`, updated `_parseSearchTrack` with source parameter
+  - `lib/providers/extension_provider.dart`: Added `SearchBehavior.getThumbnailSize()`, `clearError()`
+  - `lib/screens/home_tab.dart`: Dynamic thumbnail size based on extension config
+  - `lib/screens/settings/extensions_page.dart`: Improved error handling
+  - `lib/services/platform_bridge.dart`: Added `upgradeExtension()`, `checkExtensionUpgrade()`, `removeExtension()`
+- **iOS Changes**:
+  - `ios/Runner/AppDelegate.swift`: Added `upgradeExtension`, `checkExtensionUpgrade` handlers
+- **Android Changes**:
+  - `android/app/src/main/kotlin/com/zarz/spotiflac/MainActivity.kt`: Already had upgrade methods
+
+---
+
+## [2.2.8] - 2026-01-12
+
+### Added
+
+- **Multi-Select Batch Delete**: Long-press tracks in History to enter selection mode
+  - Select multiple tracks at once
+  - "Select All" and "Delete Selected" actions
+  - Modern Material 3 bottom action bar (slides up from bottom)
+  - Works in both grid and list view modes
+- **History Filter Tabs**: Filter history by All/Albums/Singles
+  - Album = tracks where album has >1 track in history
+  - Single = tracks where album has only 1 track in history
+  - Filter chips show counts for each category
+- **Album Grouping View**: When "Albums" filter is selected, tracks are grouped by album
+  - Album cards displayed in 2-column grid with cover art and track count badge
+  - Tap album to open dedicated album detail screen
+  - Album detail shows all downloaded tracks from that album
+  - Multi-select delete support within album view
+  - Auto-navigates back when album has <2 tracks remaining
+
+### Changed
+
+- **Issue Templates**: Updated version confirmation checkbox to specify "(Stable Version)"
+
+---
+
+## [2.2.7] - 2026-01-11
+
+### Added
+
+- **CSV Import Metadata Enrichment**: Tracks imported from CSV now automatically fetch metadata from Deezer
+  - Cover art, duration, track/disc number fetched via ISRC lookup
+  - Fallback to text search (artist + track name) when ISRC not found in Deezer
+  - Progress dialog shows enrichment status during import
+  - Ensures downloaded files have proper cover art and metadata
+- **Deezer Metadata Support**: Enhanced metadata viewer for Deezer tracks
+  - "Open in Deezer" button for Deezer-sourced tracks (opens app or web)
+  - Displays "Deezer ID" instead of "Spotify ID" when applicable
+- **Smart Tag Injection**: Filename format editor intelligently handles separators
+  - Auto-detects if " - " is needed between tags
+  - Prevents double separators or missing spaces
+- **Dynamic Source Info**: Search source selector now shows helpful context
+  - "No login required" for Deezer
+  - "Requires credentials" for Spotify
+
+### Changed
+
+- **UI Modernization**: Major UI consistency updates across the app
+  - **Unified App Bars**: Home, History, and Settings now share identical behavior
+    - Lowered expanded header for easier one-handed reachability
+    - Dynamic title text scaling (20px to 34px)
+  - **Appearance Settings**: Completely redesigned appearance page
+    - New "Theme Preview" card showing visualizing current theme
+    - Modern color palette picker replacing old color dots
+    - Clean, grouped layout
+    - "AMOLED Dark" switch is now hidden when using Light Mode
+  - **App Logo**: Refined logo style on Home and About screens
+    - Inverted colors: Filled primary color circle with on-color icon
+    - Removed padding for a cleaner, bolder look
+  - **Material 3 Switches**: Added checkmark icon to active switches
+- **UI Modernization (Global)**: Complete design refresh for a cleaner, modern look
+  - **Rounded Corners**: Standardized 16px radius for all cards, buttons, and input fields
+  - **Transparent Elements**: Applied subtle transparency to input fields and containers using `surfaceContainerHighest`
+  - **Consistent Buttons**: Unified button styling across the app (pill shape, 16px radius)
+- **Options Settings Redesign**: improved layout and usability
+  - **Search Source Priority**: Moved "Search Source" section to the very top for quick access
+  - **Compact Source Selector**: Redesigned provider toggle (Deezer/Spotify) to be compact and consistent
+  - **Credentials Workflow**: Reorganized Custom Credentials settings; toggle now auto-prompts if credentials missing
+  - **Modern Credentials Dialog**: Totally redesigned input dialog for Spotify Client ID/Secret
+- **Filename Format Editor 2.0**:
+  - **Modern Sheet UI**: Replaced legacy dialog with a clean, full-width bottom sheet
+  - **Tag Chips**: Added clickable chips ({artist}, {title}) for one-tap insertion
+  - **Smart Formatting**: Automatically injects separators (" - ") when adding tags for faster editing
+
+### Fixed
+
+- **CSV Import Missing Cover Art**: Fixed tracks from CSV having no cover art in download history
+  - Cover URL now properly fetched from Deezer during enrichment
+  - Falls back to text search when ISRC lookup fails
+- **CSV Import Missing Duration**: Fixed duration showing 0:00 for CSV-imported tracks
+  - Duration now fetched from Deezer metadata during enrichment
+- **Disc Number Not Displayed**: Fixed disc number not showing in track metadata screen
+  - Changed condition from `discNumber > 0` to `discNumber > 0`
+  - Now displays disc 1 instead of hiding it
+- **Download History Using Wrong Track Data**: Fixed history using original CSV data instead of enriched data
+  - Now uses `trackToDownload` (enriched) instead of `item.track` (original)
+
+### Technical
+
+- Updated `lib/services/csv_import_service.dart`:
+  - Added `_enrichTracksMetadata()` with ISRC lookup + text search fallback
+  - Added progress callback for UI feedback
+- Updated `lib/screens/home_tab.dart`:
+  - Added progress dialog during CSV enrichment
+- Updated `lib/providers/download_queue_provider.dart`:
+  - Uses enriched track data for download history
+- Updated `lib/screens/track_metadata_screen.dart`:
+  - Show disc number when > 0 (was > 1)
+- Updated `go_backend/metadata.go`:
+  - Added `TotalSamples` to `AudioQuality` struct for duration calculation
+- Updated `go_backend/exports.go`:
+  - `ReadFileMetadata` now returns duration calculated from FLAC stream info
+- Updated `AppTheme` with new `InputDecorationTheme` and `ButtonTheme` definitions
+- Refactored `DownloadSettingsPage` to use new `_showFormatEditor` with cursor-aware capabilities
+- Optimized various dialogs to use `showModalBottomSheet` with `isScrollControlled` for better keyboard handling
+
+---
+
+## [2.2.6] - 2026-01-11
+
+### Fixed
+
+- **Release Mode Logging**: Flutter app logs now properly captured in release builds
+  - Previously only Go backend logs appeared when "Detailed Logging" was enabled
+  - Now both Flutter and Go logs are captured in release mode
+  - Bypasses Logger package which filters logs in release mode
+
+### Added
+
+- **Detailed Deezer Search Logging**: Better debugging for search issues
+  - Logs API URLs, response counts, and errors
+  - Helps diagnose geo-restriction and API issues
+  - Detects Deezer API error responses
+
+### Changed
+
+- **Home Screen Logo**: Replaced music note icon with app logo
+  - Uses `assets/images/logo.png`
+  - Rounded corners (24px radius)
+  - Fallback to music note icon if logo fails to load
+- **About Page Logo**: Removed shadow/border from logo
+  - Cleaner appearance without background container
+- **About Page Icon Alignment**: Icons now aligned with contributor avatars
+  - DoubleDouble and DAB Music icons use 40x40 area
+  - Text now properly aligned with contributor items
+
 ## [2.2.5] - 2026-01-10
 
 ### Added

README.md

@@ -1,5 +1,6 @@
 [![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/cd205e22783a179aab80a2f0cc4445c84e59615a08c11d6e722ab4692c26ac37)
+[![VirusTotal](https://img.shields.io/badge/VirusTotal-Safe-brightgreen?style=for-the-badge&logo=virustotal)](https://www.virustotal.com/gui/file/e1c527eacb6f5ce527af214a75aab8da060c2afc629825fff24af858439e7e6b)
+[![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">
 
@@ -23,34 +24,58 @@ Get Spotify tracks in true FLAC from Tidal, Qobuz & Amazon Music — no account
   <img src="assets/images/4.jpg?v=2" width="200" />
 </p>
 
-## Metadata Source
+## Search Source
 
-SpotiFLAC supports two metadata sources for searching tracks:
+SpotiFLAC supports two search sources:
 
-| Source | Pros | Cons |
+| Source | Setup |
-|--------|------|------|
+|--------|-------|
-| **Deezer** (Default) | No developer account needed, rate limit per user IP | Slightly less comprehensive catalog |
+| **Deezer** (Default) | No setup required |
-| **Spotify** | More comprehensive catalog, better search results | Requires developer API credentials to avoid rate limiting |
+| **Spotify** | Install **Spotify Web** extension from the Store, or use your own [Spotify Developer](https://developer.spotify.com) Client ID & Secret in Settings |
 
-### Using Spotify
+## Extensions
-To use Spotify as your search source without hitting rate limits:
+
-1. Create a Spotify Developer account at [developer.spotify.com](https://developer.spotify.com)
+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.
-2. Create an app to get your Client ID and Client Secret
+
-3. Go to **Settings > Options > Spotify API > Change from Deezer to Spotify > Input Custom Credentials**
+### Installing Extensions
-4. Enter your Client ID and Secret
+1. Go to **Store** tab in the app
-5. Change **Search Source** to Spotify
+2. Browse and install extensions with one tap
+3. Or download a `.spotiflac-ext` file and install manually via **Settings > Extensions**
+4. Configure extension settings if needed
+5. Set provider priority in **Settings > Extensions > Provider Priority**
+
+### Developing Extensions
+Want to create your own extension? Check out the [Extension Development Guide](https://zarz.moe/docs) for complete documentation.
 
 ## Other project
 
 ### [SpotiFLAC (Desktop)](https://github.com/afkarxyz/SpotiFLAC)
 Get Spotify tracks in true FLAC from Tidal, Qobuz & Amazon Music for Windows, macOS & Linux
 
+## FAQ
+
+**Q: Why is my download failing with "Song not found"?**  
+A: The track may not be available on Tidal, Qobuz, or Amazon Music. Try enabling more download services in Settings > Download > Provider Priority, or install additional extensions from the Store.
+
+**Q: Why are some tracks downloading in lower quality?**  
+A: Quality depends on what's available from the streaming service. Tidal offers up to 24-bit/192kHz, Qobuz up to 24-bit/192kHz, and Amazon up to 24-bit/48kHz. The app automatically selects the best available quality.
+
+**Q: Can I download my Spotify playlists?**  
+A: Yes! Just paste the Spotify playlist URL in the search bar. The app will fetch all tracks and queue them for download.
+
+**Q: Why do I need to grant storage permission?**  
+A: The app needs permission to save downloaded files to your device. On Android 13+, you may need to grant "All files access" in Settings > Apps > SpotiFLAC > Permissions.
+
+**Q: How do I download Daily Mix or Discover Weekly?**  
+A: Install the **Spotify Web** extension from the Store. This extension can access personalized playlists that aren't available through the public API.
+
+**Q: Is this app safe?**  
+A: Yes, the app is open source and you can verify the code yourself. Each release is scanned with VirusTotal (see badge at top of README).
+
 [![Ko-fi](https://img.shields.io/badge/Ko--fi-Support%20Me-FF5E5B?style=for-the-badge&logo=ko-fi&logoColor=white)](https://ko-fi.com/zarzet)
 
 ## Disclaimer
 
-> **iOS Support**: This app is primarily tested on Android. iOS support is experimental and may have bugs — the developer is too poor to afford an iPhone for proper testing. If you encounter issues on iOS, please report them!
-
 This project is for **educational and private use only**. The developer does not condone or encourage copyright infringement.
 
 **SpotiFLAC** is a third-party tool and is not affiliated with, endorsed by, or connected to Spotify, Tidal, Qobuz, Amazon Music, or any other streaming service.

android/app/src/main/kotlin/com/zarz/spotiflac/MainActivity.kt

@@ -117,6 +117,13 @@ class MainActivity: FlutterActivity() {
                             }
                             result.success(null)
                         }
+                        "cancelDownload" -> {
+                            val itemId = call.argument<String>("item_id") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.cancelDownload(itemId)
+                            }
+                            result.success(null)
+                        }
                         "setDownloadDirectory" -> {
                             val path = call.argument<String>("path") ?: ""
                             withContext(Dispatchers.IO) {
@@ -218,6 +225,12 @@ class MainActivity: FlutterActivity() {
                             }
                             result.success(null)
                         }
+                        "hasSpotifyCredentials" -> {
+                            val hasCredentials = withContext(Dispatchers.IO) {
+                                Gobackend.checkSpotifyCredentials()
+                            }
+                            result.success(hasCredentials)
+                        }
                         "preWarmTrackCache" -> {
                             val tracksJson = call.argument<String>("tracks") ?: "[]"
                             withContext(Dispatchers.IO) {
@@ -317,6 +330,337 @@ class MainActivity: FlutterActivity() {
                             }
                             result.success(null)
                         }
+                        // Extension System methods
+                        "initExtensionSystem" -> {
+                            val extensionsDir = call.argument<String>("extensions_dir") ?: ""
+                            val dataDir = call.argument<String>("data_dir") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.initExtensionSystem(extensionsDir, dataDir)
+                            }
+                            result.success(null)
+                        }
+                        "loadExtensionsFromDir" -> {
+                            val dirPath = call.argument<String>("dir_path") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.loadExtensionsFromDir(dirPath)
+                            }
+                            result.success(response)
+                        }
+                        "loadExtensionFromPath" -> {
+                            val filePath = call.argument<String>("file_path") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.loadExtensionFromPath(filePath)
+                            }
+                            result.success(response)
+                        }
+                        "unloadExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.unloadExtensionByID(extensionId)
+                            }
+                            result.success(null)
+                        }
+                        "removeExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.removeExtensionByID(extensionId)
+                            }
+                            result.success(null)
+                        }
+                        "upgradeExtension" -> {
+                            val filePath = call.argument<String>("file_path") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.upgradeExtensionFromPath(filePath)
+                            }
+                            result.success(response)
+                        }
+                        "checkExtensionUpgrade" -> {
+                            val filePath = call.argument<String>("file_path") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.checkExtensionUpgradeFromPath(filePath)
+                            }
+                            result.success(response)
+                        }
+                        "getInstalledExtensions" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getInstalledExtensions()
+                            }
+                            result.success(response)
+                        }
+                        "setExtensionEnabled" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val enabled = call.argument<Boolean>("enabled") ?: false
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setExtensionEnabledByID(extensionId, enabled)
+                            }
+                            result.success(null)
+                        }
+                        "setProviderPriority" -> {
+                            val priorityJson = call.argument<String>("priority") ?: "[]"
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setProviderPriorityJSON(priorityJson)
+                            }
+                            result.success(null)
+                        }
+                        "getProviderPriority" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getProviderPriorityJSON()
+                            }
+                            result.success(response)
+                        }
+                        "setMetadataProviderPriority" -> {
+                            val priorityJson = call.argument<String>("priority") ?: "[]"
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setMetadataProviderPriorityJSON(priorityJson)
+                            }
+                            result.success(null)
+                        }
+                        "getMetadataProviderPriority" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getMetadataProviderPriorityJSON()
+                            }
+                            result.success(response)
+                        }
+                        "getExtensionSettings" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getExtensionSettingsJSON(extensionId)
+                            }
+                            result.success(response)
+                        }
+                        "setExtensionSettings" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val settingsJson = call.argument<String>("settings") ?: "{}"
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setExtensionSettingsJSON(extensionId, settingsJson)
+                            }
+                            result.success(null)
+                        }
+                        "searchTracksWithExtensions" -> {
+                            val query = call.argument<String>("query") ?: ""
+                            val limit = call.argument<Int>("limit") ?: 20
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.searchTracksWithExtensionsJSON(query, limit.toLong())
+                            }
+                            result.success(response)
+                        }
+                        "downloadWithExtensions" -> {
+                            val requestJson = call.arguments as String
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.downloadWithExtensionsJSON(requestJson)
+                            }
+                            result.success(response)
+                        }
+                        "removeExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.removeExtensionByID(extensionId)
+                            }
+                            result.success(null)
+                        }
+                        "cleanupExtensions" -> {
+                            withContext(Dispatchers.IO) {
+                                Gobackend.cleanupExtensions()
+                            }
+                            result.success(null)
+                        }
+                        // Extension Auth API methods
+                        "getExtensionPendingAuth" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getExtensionPendingAuthJSON(extensionId)
+                            }
+                            if (response.isNullOrEmpty()) {
+                                result.success(null)
+                            } else {
+                                result.success(response)
+                            }
+                        }
+                        "setExtensionAuthCode" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val authCode = call.argument<String>("auth_code") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setExtensionAuthCodeByID(extensionId, authCode)
+                            }
+                            result.success(null)
+                        }
+                        "setExtensionTokens" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val accessToken = call.argument<String>("access_token") ?: ""
+                            val refreshToken = call.argument<String>("refresh_token") ?: ""
+                            val expiresIn = call.argument<Int>("expires_in") ?: 0
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setExtensionTokensByID(extensionId, accessToken, refreshToken, expiresIn.toLong())
+                            }
+                            result.success(null)
+                        }
+                        "clearExtensionPendingAuth" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.clearExtensionPendingAuthByID(extensionId)
+                            }
+                            result.success(null)
+                        }
+                        "isExtensionAuthenticated" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val isAuth = withContext(Dispatchers.IO) {
+                                Gobackend.isExtensionAuthenticatedByID(extensionId)
+                            }
+                            result.success(isAuth)
+                        }
+                        "getAllPendingAuthRequests" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getAllPendingAuthRequestsJSON()
+                            }
+                            result.success(response)
+                        }
+                        // Extension FFmpeg API
+                        "getPendingFFmpegCommand" -> {
+                            val commandId = call.argument<String>("command_id") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getPendingFFmpegCommandJSON(commandId)
+                            }
+                            if (response.isNullOrEmpty()) {
+                                result.success(null)
+                            } else {
+                                result.success(response)
+                            }
+                        }
+                        "setFFmpegCommandResult" -> {
+                            val commandId = call.argument<String>("command_id") ?: ""
+                            val success = call.argument<Boolean>("success") ?: false
+                            val output = call.argument<String>("output") ?: ""
+                            val error = call.argument<String>("error") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.setFFmpegCommandResultByID(commandId, success, output, error)
+                            }
+                            result.success(null)
+                        }
+                        "getAllPendingFFmpegCommands" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getAllPendingFFmpegCommandsJSON()
+                            }
+                            result.success(response)
+                        }
+                        // Extension Custom Search API
+                        "customSearchWithExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val query = call.argument<String>("query") ?: ""
+                            val optionsJson = call.argument<String>("options") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.customSearchWithExtensionJSON(extensionId, query, optionsJson)
+                            }
+                            result.success(response)
+                        }
+                        "getSearchProviders" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getSearchProvidersJSON()
+                            }
+                            result.success(response)
+                        }
+                        // Extension URL Handler API
+                        "handleURLWithExtension" -> {
+                            val url = call.argument<String>("url") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.handleURLWithExtensionJSON(url)
+                            }
+                            result.success(response)
+                        }
+                        "findURLHandler" -> {
+                            val url = call.argument<String>("url") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.findURLHandlerJSON(url)
+                            }
+                            result.success(response)
+                        }
+                        "getURLHandlers" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getURLHandlersJSON()
+                            }
+                            result.success(response)
+                        }
+                        "getAlbumWithExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val albumId = call.argument<String>("album_id") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getAlbumWithExtensionJSON(extensionId, albumId)
+                            }
+                            result.success(response)
+                        }
+                        "getPlaylistWithExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val playlistId = call.argument<String>("playlist_id") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getPlaylistWithExtensionJSON(extensionId, playlistId)
+                            }
+                            result.success(response)
+                        }
+                        "getArtistWithExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val artistId = call.argument<String>("artist_id") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getArtistWithExtensionJSON(extensionId, artistId)
+                            }
+                            result.success(response)
+                        }
+                        // Extension Post-Processing API
+                        "runPostProcessing" -> {
+                            val filePath = call.argument<String>("file_path") ?: ""
+                            val metadataJson = call.argument<String>("metadata") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.runPostProcessingJSON(filePath, metadataJson)
+                            }
+                            result.success(response)
+                        }
+                        "getPostProcessingProviders" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getPostProcessingProvidersJSON()
+                            }
+                            result.success(response)
+                        }
+                        // Extension Store
+                        "initExtensionStore" -> {
+                            val cacheDir = call.argument<String>("cache_dir") ?: ""
+                            withContext(Dispatchers.IO) {
+                                Gobackend.initExtensionStoreJSON(cacheDir)
+                            }
+                            result.success(null)
+                        }
+                        "getStoreExtensions" -> {
+                            val forceRefresh = call.argument<Boolean>("force_refresh") ?: false
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getStoreExtensionsJSON(forceRefresh)
+                            }
+                            result.success(response)
+                        }
+                        "searchStoreExtensions" -> {
+                            val query = call.argument<String>("query") ?: ""
+                            val category = call.argument<String>("category") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.searchStoreExtensionsJSON(query, category)
+                            }
+                            result.success(response)
+                        }
+                        "getStoreCategories" -> {
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.getStoreCategoriesJSON()
+                            }
+                            result.success(response)
+                        }
+                        "downloadStoreExtension" -> {
+                            val extensionId = call.argument<String>("extension_id") ?: ""
+                            val destDir = call.argument<String>("dest_dir") ?: ""
+                            val response = withContext(Dispatchers.IO) {
+                                Gobackend.downloadStoreExtensionJSON(extensionId, destDir)
+                            }
+                            result.success(response)
+                        }
+                        "clearStoreCache" -> {
+                            withContext(Dispatchers.IO) {
+                                Gobackend.clearStoreCacheJSON()
+                            }
+                            result.success(null)
+                        }
                         else -> result.notImplemented()
                     }
                 } catch (e: Exception) {

crowdin.yml

@@ -0,0 +1,3 @@
+files:
+  - source: /lib/l10n/arb/app_en.arb
+    translation: /lib/l10n/arb/app_%locale_with_underscore%.arb

go_backend/amazon.go

@@ -1,9 +1,11 @@
 package gobackend
 
 import (
+	"context"
 	"bufio"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -173,7 +175,7 @@ func (a *AmazonDownloader) GetAvailableAPIs() []string {
 // downloadFromDoubleDoubleService downloads a track using DoubleDouble service (same as PC)
 // This uses submit → poll → download mechanism
 // Internal function - not exported to gomobile
-func (a *AmazonDownloader) downloadFromDoubleDoubleService(amazonURL, outputDir string) (string, string, string, error) {
+func (a *AmazonDownloader) downloadFromDoubleDoubleService(amazonURL, _ string) (string, string, string, error) {
 	var lastError error
 
 	for _, region := range a.regions {
@@ -346,13 +348,21 @@ func (a *AmazonDownloader) downloadFromDoubleDoubleService(amazonURL, outputDir
 
 // DownloadFile downloads a file from URL with User-Agent and progress tracking
 func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string) error {
+	ctx := context.Background()
+
 	// Initialize item progress (required for all downloads)
 	if itemID != "" {
 		StartItemProgress(itemID)
 		defer CompleteItemProgress(itemID)
+		ctx = initDownloadCancel(itemID)
+		defer clearDownloadCancel(itemID)
 	}
 
-	req, err := http.NewRequest("GET", downloadURL, nil)
+	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)
 	}
@@ -361,6 +371,9 @@ func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string)
 
 	resp, err := a.client.Do(req)
 	if err != nil {
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		return err
 	}
 	defer resp.Body.Close()
@@ -400,6 +413,9 @@ func (a *AmazonDownloader) DownloadFile(downloadURL, outputPath, itemID string)
 	// Check for any errors
 	if err != nil {
 		os.Remove(outputPath)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		return fmt.Errorf("download interrupted: %w", err)
 	}
 	if flushErr != nil {
@@ -527,6 +543,9 @@ 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 errors.Is(err, ErrDownloadCancelled) {
+			return AmazonDownloadResult{}, ErrDownloadCancelled
+		}
 		return AmazonDownloadResult{}, fmt.Errorf("download failed: %w", err)
 	}
 

go_backend/cancel.go

@@ -0,0 +1,79 @@
+package gobackend
+
+import (
+	"context"
+	"errors"
+	"sync"
+)
+
+// ErrDownloadCancelled is returned when a download is cancelled by the user.
+var ErrDownloadCancelled = errors.New("download cancelled")
+
+type cancelEntry struct {
+	cancel   context.CancelFunc
+	canceled bool
+}
+
+var (
+	cancelMu  sync.Mutex
+	cancelMap = make(map[string]*cancelEntry)
+)
+
+func initDownloadCancel(itemID string) context.Context {
+	if itemID == "" {
+		return context.Background()
+	}
+
+	cancelMu.Lock()
+	defer cancelMu.Unlock()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancelMap[itemID] = &cancelEntry{
+		cancel:   cancel,
+		canceled: false,
+	}
+	return ctx
+}
+
+func cancelDownload(itemID string) {
+	if itemID == "" {
+		return
+	}
+
+	cancelMu.Lock()
+	entry, ok := cancelMap[itemID]
+	if ok {
+		entry.canceled = true
+		if entry.cancel != nil {
+			entry.cancel()
+		}
+	} else {
+		cancelMap[itemID] = &cancelEntry{canceled: true}
+	}
+	cancelMu.Unlock()
+
+	// Hide progress for cancelled items.
+	RemoveItemProgress(itemID)
+}
+
+func isDownloadCancelled(itemID string) bool {
+	if itemID == "" {
+		return false
+	}
+
+	cancelMu.Lock()
+	entry, ok := cancelMap[itemID]
+	canceled := ok && entry.canceled
+	cancelMu.Unlock()
+	return canceled
+}
+
+func clearDownloadCancel(itemID string) {
+	if itemID == "" {
+		return
+	}
+
+	cancelMu.Lock()
+	delete(cancelMap, itemID)
+	cancelMu.Unlock()
+}

go_backend/cover.go

@@ -9,10 +9,20 @@ import (
 
 // Spotify image size codes (same as PC version)
 const (
-	spotifySize640 = "ab67616d0000b273" // 640x640
+	spotifySize300 = "ab67616d00001e02" // 300x300 (small)
+	spotifySize640 = "ab67616d0000b273" // 640x640 (medium)
 	spotifySizeMax = "ab67616d000082c1" // Max resolution (~2000x2000)
 )
 
+// convertSmallToMedium upgrades 300x300 cover URL to 640x640
+// Same logic as PC version for consistency
+func convertSmallToMedium(imageURL string) string {
+	if strings.Contains(imageURL, spotifySize300) {
+		return strings.Replace(imageURL, spotifySize300, spotifySize640, 1)
+	}
+	return imageURL
+}
+
 // downloadCoverToMemory downloads cover art and returns as bytes (no file creation)
 // This avoids file permission issues on Android
 func downloadCoverToMemory(coverURL string, maxQuality bool) ([]byte, error) {
@@ -20,17 +30,27 @@ func downloadCoverToMemory(coverURL string, maxQuality bool) ([]byte, error) {
 		return nil, fmt.Errorf("no cover URL provided")
 	}
 
-	fmt.Printf("[Cover] Downloading cover from: %s\n", coverURL)
+	GoLog("[Cover] Original URL: %s", coverURL)
 
-	// Upgrade to max quality if requested
+	// First upgrade small (300) to medium (640) - always do this
-	downloadURL := coverURL
+	downloadURL := convertSmallToMedium(coverURL)
+	if downloadURL != coverURL {
+		GoLog("[Cover] Upgraded 300x300 → 640x640")
+	}
+
+	// Then upgrade to max quality if requested
 	if maxQuality {
-		downloadURL = upgradeToMaxQuality(coverURL)
+		maxURL := upgradeToMaxQuality(downloadURL)
-		if downloadURL != coverURL {
+		if maxURL != downloadURL {
-			fmt.Printf("[Cover] Upgraded to max quality URL: %s\n", downloadURL)
+			downloadURL = maxURL
+			GoLog("[Cover] Upgraded to max resolution (~2000x2000)")
+		} else {
+			GoLog("[Cover] Max resolution not available, using 640x640")
 		}
 	}
 
+	GoLog("[Cover] Final URL: %s", downloadURL)
+
 	client := NewHTTPClientWithTimeout(DefaultTimeout)
 
 	// Create request with User-Agent (required by Spotify CDN)
@@ -54,12 +74,25 @@ func downloadCoverToMemory(coverURL string, maxQuality bool) ([]byte, error) {
 		return nil, fmt.Errorf("failed to read cover data: %w", err)
 	}
 
-	fmt.Printf("[Cover] Downloaded %d bytes\n", len(data))
+	// Calculate approximate resolution from file size
+	// JPEG ~2000x2000 is typically 300-600KB, 640x640 is ~50-100KB
+	sizeKB := len(data) / 1024
+	var resolution string
+	if sizeKB > 200 {
+		resolution = "~2000x2000 (hi-res)"
+	} else if sizeKB > 50 {
+		resolution = "~640x640"
+	} else {
+		resolution = "~300x300"
+	}
+	GoLog("[Cover] Downloaded %d KB (%s)", sizeKB, resolution)
+
 	return data, nil
 }
 
 // upgradeToMaxQuality upgrades Spotify cover URL to maximum quality
-// Uses same logic as PC version - replaces 640x640 size code with max resolution
+// Same logic as PC version - directly replaces 640x640 size code with max resolution
+// No HEAD verification needed - Spotify CDN always serves max resolution if available
 func upgradeToMaxQuality(coverURL string) string {
 	// Spotify image URLs can be upgraded by changing the size parameter
 	// Format: https://i.scdn.co/image/ab67616d0000b273...
@@ -67,21 +100,7 @@ func upgradeToMaxQuality(coverURL string) string {
 	// ab67616d000082c1 = Max resolution (~2000x2000)
 
 	if strings.Contains(coverURL, spotifySize640) {
-		// Try max resolution first
+		return strings.Replace(coverURL, spotifySize640, spotifySizeMax, 1)
-		maxURL := strings.Replace(coverURL, spotifySize640, spotifySizeMax, 1)
-
-		// Verify max resolution URL is available
-		client := NewHTTPClientWithTimeout(DefaultTimeout)
-		req, err := http.NewRequest("HEAD", maxURL, nil)
-		if err == nil {
-			resp, err := DoRequestWithUserAgent(client, req)
-			if err == nil {
-				resp.Body.Close()
-				if resp.StatusCode == http.StatusOK {
-					return maxURL
-				}
-			}
-		}
 	}
 
 	return coverURL
@@ -93,9 +112,12 @@ func GetCoverFromSpotify(imageURL string, maxQuality bool) string {
 		return ""
 	}
 
+	// Always upgrade small to medium first
+	result := convertSmallToMedium(imageURL)
+
 	if maxQuality {
-		return upgradeToMaxQuality(imageURL)
+		result = upgradeToMaxQuality(result)
 	}
 
-	return imageURL
+	return result
 }

go_backend/deezer.go

@@ -58,27 +58,27 @@ func GetDeezerClient() *DeezerClient {
 
 // Deezer API response types
 type deezerTrack struct {
-	ID             int64  `json:"id"`
+	ID            int64             `json:"id"`
-	Title          string `json:"title"`
+	Title         string            `json:"title"`
-	Duration       int    `json:"duration"` // in seconds
+	Duration      int               `json:"duration"` // in seconds
-	TrackPosition  int    `json:"track_position"`
+	TrackPosition int               `json:"track_position"`
-	DiskNumber     int    `json:"disk_number"`
+	DiskNumber    int               `json:"disk_number"`
-	ISRC           string `json:"isrc"`
+	ISRC          string            `json:"isrc"`
-	Link           string `json:"link"`
+	Link          string            `json:"link"`
-	ReleaseDate    string `json:"release_date"` // Sometimes at track level
+	ReleaseDate   string            `json:"release_date"` // Sometimes at track level
-	Artist         deezerArtist `json:"artist"`
+	Artist        deezerArtist      `json:"artist"`
-	Album          deezerAlbumSimple `json:"album"`
+	Album         deezerAlbumSimple `json:"album"`
-	Contributors   []deezerArtist `json:"contributors"`
+	Contributors  []deezerArtist    `json:"contributors"`
 }
 
 type deezerArtist struct {
-	ID        int64  `json:"id"`
+	ID            int64  `json:"id"`
-	Name      string `json:"name"`
+	Name          string `json:"name"`
-	Picture   string `json:"picture"`
+	Picture       string `json:"picture"`
 	PictureMedium string `json:"picture_medium"`
 	PictureBig    string `json:"picture_big"`
 	PictureXL     string `json:"picture_xl"`
-	NbFan     int    `json:"nb_fan"`
+	NbFan         int    `json:"nb_fan"`
 }
 
 type deezerAlbumSimple struct {
@@ -89,10 +89,9 @@ type deezerAlbumSimple struct {
 	CoverBig    string `json:"cover_big"`
 	CoverXL     string `json:"cover_xl"`
 	ReleaseDate string `json:"release_date"` // Sometimes at album level
+	RecordType  string `json:"record_type"`  // album, single, ep, compile
 }
-// ... (skip other structs as they are fine/unchanged) ...
 
-// ... (in convertTrack) ...
 func (c *DeezerClient) convertTrack(track deezerTrack) TrackMetadata {
 	artistName := track.Artist.Name
 	if len(track.Contributors) > 0 {
@@ -137,17 +136,18 @@ func (c *DeezerClient) convertTrack(track deezerTrack) TrackMetadata {
 }
 
 type deezerAlbumFull struct {
-	ID          int64  `json:"id"`
+	ID           int64          `json:"id"`
-	Title       string `json:"title"`
+	Title        string         `json:"title"`
-	Cover       string `json:"cover"`
+	Cover        string         `json:"cover"`
-	CoverMedium string `json:"cover_medium"`
+	CoverMedium  string         `json:"cover_medium"`
-	CoverBig    string `json:"cover_big"`
+	CoverBig     string         `json:"cover_big"`
-	CoverXL     string `json:"cover_xl"`
+	CoverXL      string         `json:"cover_xl"`
-	ReleaseDate string `json:"release_date"`
+	ReleaseDate  string         `json:"release_date"`
-	NbTracks    int    `json:"nb_tracks"`
+	NbTracks     int            `json:"nb_tracks"`
-	Artist      deezerArtist `json:"artist"`
+	RecordType   string         `json:"record_type"` // album, single, ep, compile
+	Artist       deezerArtist   `json:"artist"`
 	Contributors []deezerArtist `json:"contributors"`
-	Tracks      struct {
+	Tracks       struct {
 		Data []deezerTrack `json:"data"`
 	} `json:"tracks"`
 }
@@ -164,17 +164,17 @@ type deezerArtistFull struct {
 }
 
 type deezerPlaylistFull struct {
-	ID          int64  `json:"id"`
+	ID            int64  `json:"id"`
-	Title       string `json:"title"`
+	Title         string `json:"title"`
-	Picture     string `json:"picture"`
+	Picture       string `json:"picture"`
 	PictureMedium string `json:"picture_medium"`
 	PictureBig    string `json:"picture_big"`
 	PictureXL     string `json:"picture_xl"`
-	NbTracks    int    `json:"nb_tracks"`
+	NbTracks      int    `json:"nb_tracks"`
-	Creator     struct {
+	Creator       struct {
 		Name string `json:"name"`
 	} `json:"creator"`
-	Tracks      struct {
+	Tracks struct {
 		Data []deezerTrack `json:"data"`
 	} `json:"tracks"`
 }
@@ -182,11 +182,14 @@ type deezerPlaylistFull struct {
 // SearchAll searches for tracks and artists on Deezer
 // NOTE: ISRC is NOT fetched during search for performance - use GetTrackISRC when needed for download
 func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit, artistLimit int) (*SearchAllResult, error) {
+	GoLog("[Deezer] SearchAll: query=%q, trackLimit=%d, artistLimit=%d\n", query, trackLimit, artistLimit)
+
 	cacheKey := fmt.Sprintf("deezer:all:%s:%d:%d", query, trackLimit, artistLimit)
 
 	c.cacheMu.RLock()
 	if entry, ok := c.searchCache[cacheKey]; ok && !entry.isExpired() {
 		c.cacheMu.RUnlock()
+		GoLog("[Deezer] SearchAll: returning cached result\n")
 		return entry.data.(*SearchAllResult), nil
 	}
 	c.cacheMu.RUnlock()
@@ -198,13 +201,28 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 
 	// Search tracks - NO ISRC fetch for performance
 	trackURL := fmt.Sprintf("%s/track?q=%s&limit=%d", deezerSearchURL, url.QueryEscape(query), trackLimit)
+	GoLog("[Deezer] Fetching tracks from: %s\n", trackURL)
+
 	var trackResp struct {
-		Data []deezerTrack `json:"data"`
+		Data  []deezerTrack `json:"data"`
+		Error *struct {
+			Type    string `json:"type"`
+			Message string `json:"message"`
+			Code    int    `json:"code"`
+		} `json:"error"`
 	}
 	if err := c.getJSON(ctx, trackURL, &trackResp); err != nil {
+		GoLog("[Deezer] Track search failed: %v\n", err)
 		return nil, fmt.Errorf("deezer track search failed: %w", err)
 	}
 
+	if trackResp.Error != nil {
+		GoLog("[Deezer] API error: type=%s, code=%d, message=%s\n", trackResp.Error.Type, trackResp.Error.Code, trackResp.Error.Message)
+		return nil, fmt.Errorf("deezer API error: %s (code %d)", trackResp.Error.Message, trackResp.Error.Code)
+	}
+
+	GoLog("[Deezer] Got %d tracks from API\n", len(trackResp.Data))
+
 	for _, track := range trackResp.Data {
 		// Convert directly without fetching ISRC - much faster
 		result.Tracks = append(result.Tracks, c.convertTrack(track))
@@ -212,21 +230,37 @@ func (c *DeezerClient) SearchAll(ctx context.Context, query string, trackLimit,
 
 	// Search artists
 	artistURL := fmt.Sprintf("%s/artist?q=%s&limit=%d", deezerSearchURL, url.QueryEscape(query), artistLimit)
+	GoLog("[Deezer] Fetching artists from: %s\n", artistURL)
+
 	var artistResp struct {
-		Data []deezerArtist `json:"data"`
+		Data  []deezerArtist `json:"data"`
+		Error *struct {
+			Type    string `json:"type"`
+			Message string `json:"message"`
+			Code    int    `json:"code"`
+		} `json:"error"`
 	}
 	if err := c.getJSON(ctx, artistURL, &artistResp); err == nil {
-		for _, artist := range artistResp.Data {
+		if artistResp.Error != nil {
-			result.Artists = append(result.Artists, SearchArtistResult{
+			GoLog("[Deezer] Artist API error: type=%s, code=%d, message=%s\n", artistResp.Error.Type, artistResp.Error.Code, artistResp.Error.Message)
-				ID:         fmt.Sprintf("deezer:%d", artist.ID),
+		} else {
-				Name:       artist.Name,
+			GoLog("[Deezer] Got %d artists from API\n", len(artistResp.Data))
-				Images:     c.getBestArtistImage(artist),
+			for _, artist := range artistResp.Data {
-				Followers:  artist.NbFan,
+				result.Artists = append(result.Artists, SearchArtistResult{
-				Popularity: 0,
+					ID:         fmt.Sprintf("deezer:%d", artist.ID),
-			})
+					Name:       artist.Name,
+					Images:     c.getBestArtistImage(artist),
+					Followers:  artist.NbFan,
+					Popularity: 0,
+				})
+			}
 		}
+	} else {
+		GoLog("[Deezer] Artist search failed: %v\n", err)
 	}
 
+	GoLog("[Deezer] SearchAll complete: %d tracks, %d artists\n", len(result.Tracks), len(result.Artists))
+
 	// Cache result
 	c.cacheMu.Lock()
 	c.searchCache[cacheKey] = &cacheEntry{
@@ -291,6 +325,12 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 	isrcMap := c.fetchISRCsParallel(ctx, album.Tracks.Data)
 
 	tracks := make([]AlbumTrackMetadata, 0, len(album.Tracks.Data))
+	// Normalize record_type (Deezer uses "compile" instead of "compilation")
+	albumType := album.RecordType
+	if albumType == "compile" {
+		albumType = "compilation"
+	}
+
 	for _, track := range album.Tracks.Data {
 		trackIDStr := fmt.Sprintf("%d", track.ID)
 		isrc := isrcMap[trackIDStr]
@@ -310,6 +350,7 @@ func (c *DeezerClient) GetAlbum(ctx context.Context, albumID string) (*AlbumResp
 			ExternalURL: track.Link,
 			ISRC:        isrc,
 			AlbumID:     fmt.Sprintf("deezer:%d", album.ID),
+			AlbumType:   albumType,
 		})
 	}
 
@@ -603,8 +644,6 @@ func (c *DeezerClient) GetTrackISRC(ctx context.Context, trackID string) (string
 	return fullTrack.ISRC, nil
 }
 
-
-
 func (c *DeezerClient) getBestArtistImage(artist deezerArtist) string {
 	if artist.PictureXL != "" {
 		return artist.PictureXL

go_backend/duplicate.go

@@ -103,6 +103,18 @@ 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
+	}
+
+	idx.mu.Lock()
+	defer idx.mu.Unlock()
+
+	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) {
@@ -138,7 +150,18 @@ func checkISRCExistsInternal(outputDir, isrc string) (string, bool) {
 
 	// Use index for fast lookup
 	idx := GetISRCIndex(outputDir)
-	return idx.lookup(isrc)
+	filePath, exists := idx.lookup(isrc)
+	if !exists {
+		return "", false
+	}
+
+	if !CheckFileExists(filePath) {
+		// Stale index entry; remove it and return not found.
+		idx.remove(isrc)
+		return "", false
+	}
+
+	return filePath, true
 }
 
 // CheckISRCExists is the exported version for gomobile (returns string, error)

go_backend/extension_manifest.go

@@ -0,0 +1,315 @@
+// Package gobackend provides extension manifest parsing and validation
+package gobackend
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+// ExtensionType represents the type of extension
+type ExtensionType string
+
+const (
+	ExtensionTypeMetadataProvider ExtensionType = "metadata_provider"
+	ExtensionTypeDownloadProvider ExtensionType = "download_provider"
+)
+
+// SettingType represents the type of a setting field
+type SettingType string
+
+const (
+	SettingTypeString SettingType = "string"
+	SettingTypeNumber SettingType = "number"
+	SettingTypeBool   SettingType = "boolean"
+	SettingTypeSelect SettingType = "select"
+)
+
+// 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
+}
+
+// ExtensionSetting defines a configurable setting for an extension
+type ExtensionSetting struct {
+	Key         string      `json:"key"`
+	Type        SettingType `json:"type"`
+	Label       string      `json:"label"`
+	Description string      `json:"description,omitempty"`
+	Required    bool        `json:"required,omitempty"`
+	Secret      bool        `json:"secret,omitempty"`
+	Default     interface{} `json:"default,omitempty"`
+	Options     []string    `json:"options,omitempty"` // For select type
+}
+
+// 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
+}
+
+// QualitySpecificSetting represents a setting that's specific to a quality option
+type QualitySpecificSetting struct {
+	Key         string      `json:"key"`
+	Type        SettingType `json:"type"`
+	Label       string      `json:"label"`
+	Description string      `json:"description,omitempty"`
+	Required    bool        `json:"required,omitempty"`
+	Secret      bool        `json:"secret,omitempty"`
+	Default     interface{} `json:"default,omitempty"`
+	Options     []string    `json:"options,omitempty"` // For select type
+}
+
+// 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
+}
+
+// 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")
+}
+
+// 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
+}
+
+// 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"])
+}
+
+// PostProcessingConfig defines post-processing capabilities
+type PostProcessingConfig struct {
+	Enabled bool                 `json:"enabled"`         // Whether extension provides post-processing
+	Hooks   []PostProcessingHook `json:"hooks,omitempty"` // Available hooks
+}
+
+// ExtensionManifest represents the manifest.json of an extension
+type ExtensionManifest struct {
+	Name                   string                `json:"name"`
+	DisplayName            string                `json:"displayName"`
+	Version                string                `json:"version"`
+	Author                 string                `json:"author"`
+	Description            string                `json:"description"`
+	Homepage               string                `json:"homepage,omitempty"`
+	Icon                   string                `json:"icon,omitempty"` // Icon filename (e.g., "icon.png")
+	Types                  []ExtensionType       `json:"type"`
+	Permissions            ExtensionPermissions  `json:"permissions"`
+	Settings               []ExtensionSetting    `json:"settings,omitempty"`
+	QualityOptions         []QualityOption       `json:"qualityOptions,omitempty"` // Custom quality options for download providers
+	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
+}
+
+// ManifestValidationError represents a validation error in the manifest
+type ManifestValidationError struct {
+	Field   string
+	Message string
+}
+
+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 {
+		return nil, fmt.Errorf("failed to parse manifest JSON: %w", err)
+	}
+
+	if err := manifest.Validate(); err != nil {
+		return nil, err
+	}
+
+	return &manifest, nil
+}
+
+// Validate checks if the manifest has all required fields and valid values
+func (m *ExtensionManifest) Validate() error {
+	// Check required fields
+	if strings.TrimSpace(m.Name) == "" {
+		return &ManifestValidationError{Field: "name", Message: "name is required"}
+	}
+
+	if strings.TrimSpace(m.Version) == "" {
+		return &ManifestValidationError{Field: "version", Message: "version is required"}
+	}
+
+	if strings.TrimSpace(m.Author) == "" {
+		return &ManifestValidationError{Field: "author", Message: "author is required"}
+	}
+
+	if strings.TrimSpace(m.Description) == "" {
+		return &ManifestValidationError{Field: "description", Message: "description is required"}
+	}
+
+	if len(m.Types) == 0 {
+		return &ManifestValidationError{Field: "type", Message: "at least one type is required"}
+	}
+
+	// Validate extension types
+	for _, t := range m.Types {
+		if t != ExtensionTypeMetadataProvider && t != ExtensionTypeDownloadProvider {
+			return &ManifestValidationError{
+				Field:   "type",
+				Message: fmt.Sprintf("invalid extension type: %s (must be 'metadata_provider' or 'download_provider')", t),
+			}
+		}
+	}
+
+	// Validate settings if present
+	for i, setting := range m.Settings {
+		if strings.TrimSpace(setting.Key) == "" {
+			return &ManifestValidationError{
+				Field:   fmt.Sprintf("settings[%d].key", i),
+				Message: "setting key is required",
+			}
+		}
+
+		if setting.Type == "" {
+			return &ManifestValidationError{
+				Field:   fmt.Sprintf("settings[%d].type", i),
+				Message: "setting type is required",
+			}
+		}
+
+		// Validate setting type
+		validTypes := map[SettingType]bool{
+			SettingTypeString: true,
+			SettingTypeNumber: true,
+			SettingTypeBool:   true,
+			SettingTypeSelect: true,
+		}
+		if !validTypes[setting.Type] {
+			return &ManifestValidationError{
+				Field:   fmt.Sprintf("settings[%d].type", i),
+				Message: fmt.Sprintf("invalid setting type: %s", setting.Type),
+			}
+		}
+
+		// Select type requires options
+		if setting.Type == SettingTypeSelect && len(setting.Options) == 0 {
+			return &ManifestValidationError{
+				Field:   fmt.Sprintf("settings[%d].options", i),
+				Message: "select type requires options",
+			}
+		}
+	}
+
+	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 {
+			return true
+		}
+	}
+	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 {
+		allowed = strings.ToLower(strings.TrimSpace(allowed))
+		if allowed == domain {
+			return true
+		}
+		// Support wildcard subdomains (e.g., *.example.com)
+		if strings.HasPrefix(allowed, "*.") {
+			suffix := allowed[1:] // Remove the *
+			if strings.HasSuffix(domain, suffix) {
+				return true
+			}
+		}
+	}
+	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
+	}
+
+	// Parse URL to get host
+	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
+		}
+	}
+	return false
+}
+
+// GetPostProcessingHooks returns all post-processing hooks
+func (m *ExtensionManifest) GetPostProcessingHooks() []PostProcessingHook {
+	if m.PostProcessing == nil {
+		return nil
+	}
+	return m.PostProcessing.Hooks
+}
+
+// ToJSON serializes the manifest to JSON
+func (m *ExtensionManifest) ToJSON() ([]byte, error) {
+	return json.Marshal(m)
+}

go_backend/extension_runtime.go

@@ -0,0 +1,340 @@
+// Package gobackend provides extension runtime with sandboxed execution
+package gobackend
+
+import (
+	"net/http"
+	"net/url"
+	"sync"
+	"time"
+
+	"github.com/dop251/goja"
+)
+
+// Default timeout for JS execution (30 seconds)
+const DefaultJSTimeout = 30 * time.Second
+
+// Global auth state for extensions (stores pending auth codes)
+var (
+	extensionAuthState   = make(map[string]*ExtensionAuthState)
+	extensionAuthStateMu sync.RWMutex
+)
+
+// ExtensionAuthState holds auth state for an extension
+type ExtensionAuthState struct {
+	PendingAuthURL  string
+	AuthCode        string
+	AccessToken     string
+	RefreshToken    string
+	ExpiresAt       time.Time
+	IsAuthenticated bool
+	// PKCE support
+	PKCEVerifier  string
+	PKCEChallenge string
+}
+
+// PendingAuthRequest holds a pending OAuth request that needs Flutter to open URL
+type PendingAuthRequest struct {
+	ExtensionID string
+	AuthURL     string
+	CallbackURL string
+}
+
+// Global pending auth requests (Flutter polls this)
+var (
+	pendingAuthRequests   = make(map[string]*PendingAuthRequest)
+	pendingAuthRequestsMu sync.RWMutex
+)
+
+// GetPendingAuthRequest returns pending auth request for an extension (called from Flutter)
+func GetPendingAuthRequest(extensionID string) *PendingAuthRequest {
+	pendingAuthRequestsMu.RLock()
+	defer pendingAuthRequestsMu.RUnlock()
+	return pendingAuthRequests[extensionID]
+}
+
+// ClearPendingAuthRequest clears pending auth request (called from Flutter after opening URL)
+func ClearPendingAuthRequest(extensionID string) {
+	pendingAuthRequestsMu.Lock()
+	defer pendingAuthRequestsMu.Unlock()
+	delete(pendingAuthRequests, extensionID)
+}
+
+// SetExtensionAuthCode sets auth code for an extension (called from Flutter after OAuth callback)
+func SetExtensionAuthCode(extensionID string, authCode string) {
+	extensionAuthStateMu.Lock()
+	defer extensionAuthStateMu.Unlock()
+
+	state, exists := extensionAuthState[extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[extensionID] = state
+	}
+	state.AuthCode = authCode
+}
+
+// SetExtensionTokens sets access/refresh tokens for an extension
+func SetExtensionTokens(extensionID string, accessToken, refreshToken string, expiresAt time.Time) {
+	extensionAuthStateMu.Lock()
+	defer extensionAuthStateMu.Unlock()
+
+	state, exists := extensionAuthState[extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[extensionID] = state
+	}
+	state.AccessToken = accessToken
+	state.RefreshToken = refreshToken
+	state.ExpiresAt = expiresAt
+	state.IsAuthenticated = accessToken != ""
+}
+
+// ExtensionRuntime provides sandboxed APIs for extensions
+type ExtensionRuntime struct {
+	extensionID string
+	manifest    *ExtensionManifest
+	settings    map[string]interface{}
+	httpClient  *http.Client
+	cookieJar   http.CookieJar
+	dataDir     string
+	vm          *goja.Runtime
+}
+
+// NewExtensionRuntime creates a new runtime for an extension
+func NewExtensionRuntime(ext *LoadedExtension) *ExtensionRuntime {
+	// Create a cookie jar for this extension
+	jar, _ := newSimpleCookieJar()
+
+	runtime := &ExtensionRuntime{
+		extensionID: ext.ID,
+		manifest:    ext.Manifest,
+		settings:    make(map[string]interface{}),
+		cookieJar:   jar,
+		dataDir:     ext.DataDir,
+		vm:          ext.VM,
+	}
+
+	// Create HTTP client with redirect validation to prevent SSRF via open redirect
+	client := &http.Client{
+		Timeout: 30 * time.Second,
+		Jar:     jar,
+		CheckRedirect: func(req *http.Request, via []*http.Request) error {
+			// Validate redirect target domain against allowed domains
+			domain := req.URL.Hostname()
+			if !ext.Manifest.IsDomainAllowed(domain) {
+				GoLog("[Extension:%s] Redirect blocked: domain '%s' not in allowed list\n", ext.ID, domain)
+				return &RedirectBlockedError{Domain: domain}
+			}
+			// Also block redirects to private/local networks (SSRF protection)
+			if isPrivateIP(domain) {
+				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
+			}
+			return nil
+		},
+	}
+	runtime.httpClient = client
+
+	return runtime
+}
+
+// RedirectBlockedError is returned when a redirect is blocked due to domain validation
+type RedirectBlockedError struct {
+	Domain    string
+	IsPrivate bool
+}
+
+func (e *RedirectBlockedError) Error() string {
+	if e.IsPrivate {
+		return "redirect blocked: private/local network access denied"
+	}
+	return "redirect blocked: domain '" + e.Domain + "' not in allowed list"
+}
+
+// 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.", // Link-local
+		"::1",      // IPv6 localhost
+		"fc00:",    // IPv6 private
+		"fe80:",    // IPv6 link-local
+	}
+
+	hostLower := host
+	for _, pattern := range privatePatterns {
+		if hostLower == pattern || len(hostLower) > len(pattern) && hostLower[:len(pattern)] == pattern {
+			return true
+		}
+	}
+
+	// Also block .local domains
+	if len(host) > 6 && host[len(host)-6:] == ".local" {
+		return true
+	}
+
+	return false
+}
+
+// simpleCookieJar is a simple in-memory cookie jar
+type simpleCookieJar struct {
+	cookies map[string][]*http.Cookie
+	mu      sync.RWMutex
+}
+
+func newSimpleCookieJar() (*simpleCookieJar, error) {
+	return &simpleCookieJar{
+		cookies: make(map[string][]*http.Cookie),
+	}, nil
+}
+
+func (j *simpleCookieJar) SetCookies(u *url.URL, cookies []*http.Cookie) {
+	j.mu.Lock()
+	defer j.mu.Unlock()
+	key := u.Host
+	j.cookies[key] = append(j.cookies[key], cookies...)
+}
+
+func (j *simpleCookieJar) Cookies(u *url.URL) []*http.Cookie {
+	j.mu.RLock()
+	defer j.mu.RUnlock()
+	return j.cookies[u.Host]
+}
+
+// SetSettings updates the runtime settings
+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("clearCookies", r.httpClearCookies)
+	vm.Set("http", httpObj)
+
+	// Storage API
+	storageObj := vm.NewObject()
+	storageObj.Set("get", r.storageGet)
+	storageObj.Set("set", r.storageSet)
+	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)
+	credentialsObj.Set("remove", r.credentialsRemove)
+	credentialsObj.Set("has", r.credentialsHas)
+	vm.Set("credentials", credentialsObj)
+
+	// Auth API (for OAuth and other auth flows)
+	authObj := vm.NewObject()
+	authObj.Set("openAuthUrl", r.authOpenUrl)
+	authObj.Set("getAuthCode", r.authGetCode)
+	authObj.Set("setAuthCode", r.authSetCode)
+	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)
+	fileObj.Set("delete", r.fileDelete)
+	fileObj.Set("read", r.fileRead)
+	fileObj.Set("write", r.fileWrite)
+	fileObj.Set("copy", r.fileCopy)
+	fileObj.Set("move", r.fileMove)
+	fileObj.Set("getSize", r.fileGetSize)
+	vm.Set("file", fileObj)
+
+	// FFmpeg API (for post-processing)
+	ffmpegObj := vm.NewObject()
+	ffmpegObj.Set("execute", r.ffmpegExecute)
+	ffmpegObj.Set("getInfo", r.ffmpegGetInfo)
+	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)
+	matchingObj.Set("normalizeString", r.matchingNormalizeString)
+	vm.Set("matching", matchingObj)
+
+	// Utilities
+	utilsObj := vm.NewObject()
+	utilsObj.Set("base64Encode", r.base64Encode)
+	utilsObj.Set("base64Decode", r.base64Decode)
+	utilsObj.Set("md5", r.md5Hash)
+	utilsObj.Set("sha256", r.sha256Hash)
+	utilsObj.Set("hmacSHA256", r.hmacSHA256)
+	utilsObj.Set("hmacSHA256Base64", r.hmacSHA256Base64)
+	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)
+	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)
+	logObj.Set("warn", r.logWarn)
+	logObj.Set("error", r.logError)
+	vm.Set("log", logObj)
+
+	// Go backend functions
+	gobackendObj := vm.NewObject()
+	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)
+
+	// Global atob/btoa - Base64 encoding (browser-compatible)
+	vm.Set("atob", r.atobPolyfill)
+	vm.Set("btoa", r.btoaPolyfill)
+
+	// TextEncoder/TextDecoder constructors
+	r.registerTextEncoderDecoder(vm)
+
+	// URL class for URL parsing
+	r.registerURLClass(vm)
+
+	// JSON global (browser-compatible)
+	r.registerJSONGlobal(vm)
+}

go_backend/extension_runtime_auth.go

@@ -0,0 +1,547 @@
+// Package gobackend provides Auth API and PKCE support for extension runtime
+package gobackend
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== Auth API (OAuth Support) ====================
+
+// authOpenUrl requests Flutter to open an OAuth URL
+func (r *ExtensionRuntime) authOpenUrl(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "auth URL is required",
+		})
+	}
+
+	authURL := call.Arguments[0].String()
+	callbackURL := ""
+	if len(call.Arguments) > 1 && !goja.IsUndefined(call.Arguments[1]) {
+		callbackURL = call.Arguments[1].String()
+	}
+
+	// Store pending auth request for Flutter to pick up
+	pendingAuthRequestsMu.Lock()
+	pendingAuthRequests[r.extensionID] = &PendingAuthRequest{
+		ExtensionID: r.extensionID,
+		AuthURL:     authURL,
+		CallbackURL: callbackURL,
+	}
+	pendingAuthRequestsMu.Unlock()
+
+	// Update auth state
+	extensionAuthStateMu.Lock()
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[r.extensionID] = state
+	}
+	state.PendingAuthURL = authURL
+	state.AuthCode = "" // Clear any previous auth code
+	extensionAuthStateMu.Unlock()
+
+	GoLog("[Extension:%s] Auth URL requested: %s\n", r.extensionID, authURL)
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"message": "Auth URL will be opened by the app",
+	})
+}
+
+// authGetCode gets the auth code (set by Flutter after OAuth callback)
+func (r *ExtensionRuntime) authGetCode(call goja.FunctionCall) goja.Value {
+	extensionAuthStateMu.RLock()
+	defer extensionAuthStateMu.RUnlock()
+
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists || state.AuthCode == "" {
+		return goja.Undefined()
+	}
+
+	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()
+	defer extensionAuthStateMu.Unlock()
+
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[r.extensionID] = state
+	}
+
+	switch v := arg.(type) {
+	case string:
+		state.AuthCode = v
+	case map[string]interface{}:
+		if code, ok := v["code"].(string); ok {
+			state.AuthCode = code
+		}
+		if accessToken, ok := v["access_token"].(string); ok {
+			state.AccessToken = accessToken
+			state.IsAuthenticated = true
+		}
+		if refreshToken, ok := v["refresh_token"].(string); ok {
+			state.RefreshToken = refreshToken
+		}
+		if expiresIn, ok := v["expires_in"].(float64); ok {
+			state.ExpiresAt = time.Now().Add(time.Duration(expiresIn) * time.Second)
+		}
+	}
+
+	return r.vm.ToValue(true)
+}
+
+// authClear clears all auth state for the extension
+func (r *ExtensionRuntime) authClear(call goja.FunctionCall) goja.Value {
+	extensionAuthStateMu.Lock()
+	delete(extensionAuthState, r.extensionID)
+	extensionAuthStateMu.Unlock()
+
+	pendingAuthRequestsMu.Lock()
+	delete(pendingAuthRequests, r.extensionID)
+	pendingAuthRequestsMu.Unlock()
+
+	GoLog("[Extension:%s] Auth state cleared\n", r.extensionID)
+	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()
+
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists {
+		return r.vm.ToValue(false)
+	}
+
+	// Check if token is expired
+	if state.IsAuthenticated && !state.ExpiresAt.IsZero() && time.Now().After(state.ExpiresAt) {
+		return r.vm.ToValue(false)
+	}
+
+	return r.vm.ToValue(state.IsAuthenticated)
+}
+
+// authGetTokens returns current tokens (for extension to use in API calls)
+func (r *ExtensionRuntime) authGetTokens(call goja.FunctionCall) goja.Value {
+	extensionAuthStateMu.RLock()
+	defer extensionAuthStateMu.RUnlock()
+
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists {
+		return r.vm.ToValue(map[string]interface{}{})
+	}
+
+	result := map[string]interface{}{
+		"access_token":     state.AccessToken,
+		"refresh_token":    state.RefreshToken,
+		"is_authenticated": state.IsAuthenticated,
+	}
+
+	if !state.ExpiresAt.IsZero() {
+		result["expires_at"] = state.ExpiresAt.Unix()
+		result["is_expired"] = time.Now().After(state.ExpiresAt)
+	}
+
+	return r.vm.ToValue(result)
+}
+
+// ==================== PKCE Support ====================
+
+// generatePKCEVerifier generates a cryptographically random code verifier
+// Length should be between 43-128 characters (RFC 7636)
+func generatePKCEVerifier(length int) (string, error) {
+	if length < 43 {
+		length = 43
+	}
+	if length > 128 {
+		length = 128
+	}
+
+	// Generate random bytes
+	bytes := make([]byte, length)
+	if _, err := rand.Read(bytes); err != nil {
+		return "", err
+	}
+
+	// Use base64url encoding without padding (RFC 7636 compliant)
+	verifier := base64.RawURLEncoding.EncodeToString(bytes)
+
+	// Trim to exact length
+	if len(verifier) > length {
+		verifier = verifier[:length]
+	}
+
+	return verifier, nil
+}
+
+// generatePKCEChallenge generates a code challenge from verifier using S256 method
+func generatePKCEChallenge(verifier string) string {
+	hash := sha256.Sum256([]byte(verifier))
+	// Base64url encode without padding (RFC 7636)
+	return base64.RawURLEncoding.EncodeToString(hash[:])
+}
+
+// authGeneratePKCE generates a PKCE code verifier and challenge pair
+// Returns: { verifier: string, challenge: string, method: "S256" }
+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 {
+			length = int(l)
+		}
+	}
+
+	verifier, err := generatePKCEVerifier(length)
+	if err != nil {
+		GoLog("[Extension:%s] PKCE generation error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	challenge := generatePKCEChallenge(verifier)
+
+	// Store in auth state for later use
+	extensionAuthStateMu.Lock()
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[r.extensionID] = state
+	}
+	state.PKCEVerifier = verifier
+	state.PKCEChallenge = challenge
+	extensionAuthStateMu.Unlock()
+
+	GoLog("[Extension:%s] PKCE generated (verifier length: %d)\n", r.extensionID, len(verifier))
+
+	return r.vm.ToValue(map[string]interface{}{
+		"verifier":  verifier,
+		"challenge": challenge,
+		"method":    "S256",
+	})
+}
+
+// authGetPKCE returns the current PKCE verifier and challenge (if generated)
+func (r *ExtensionRuntime) authGetPKCE(call goja.FunctionCall) goja.Value {
+	extensionAuthStateMu.RLock()
+	defer extensionAuthStateMu.RUnlock()
+
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists || state.PKCEVerifier == "" {
+		return r.vm.ToValue(map[string]interface{}{})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"verifier":  state.PKCEVerifier,
+		"challenge": state.PKCEChallenge,
+		"method":    "S256",
+	})
+}
+
+// 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{}{
+			"success": false,
+			"error":   "config object is required",
+		})
+	}
+
+	configObj := call.Arguments[0].Export()
+	config, ok := configObj.(map[string]interface{})
+	if !ok {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "config must be an object",
+		})
+	}
+
+	// Required fields
+	authURL, _ := config["authUrl"].(string)
+	clientID, _ := config["clientId"].(string)
+	redirectURI, _ := config["redirectUri"].(string)
+
+	if authURL == "" || clientID == "" || redirectURI == "" {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "authUrl, clientId, and redirectUri are required",
+		})
+	}
+
+	// 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{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to generate PKCE: %v", err),
+		})
+	}
+	challenge := generatePKCEChallenge(verifier)
+
+	// Store PKCE in auth state
+	extensionAuthStateMu.Lock()
+	state, exists := extensionAuthState[r.extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[r.extensionID] = state
+	}
+	state.PKCEVerifier = verifier
+	state.PKCEChallenge = challenge
+	state.AuthCode = "" // Clear any previous auth code
+	extensionAuthStateMu.Unlock()
+
+	// Build OAuth URL with PKCE parameters
+	parsedURL, err := url.Parse(authURL)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("invalid authUrl: %v", err),
+		})
+	}
+
+	query := parsedURL.Query()
+	query.Set("client_id", clientID)
+	query.Set("redirect_uri", redirectURI)
+	query.Set("response_type", "code")
+	query.Set("code_challenge", challenge)
+	query.Set("code_challenge_method", "S256")
+
+	if scope != "" {
+		query.Set("scope", scope)
+	}
+
+	// Add extra params
+	for k, v := range extraParams {
+		query.Set(k, fmt.Sprintf("%v", v))
+	}
+
+	parsedURL.RawQuery = query.Encode()
+	fullAuthURL := parsedURL.String()
+
+	// Store pending auth request for Flutter
+	pendingAuthRequestsMu.Lock()
+	pendingAuthRequests[r.extensionID] = &PendingAuthRequest{
+		ExtensionID: r.extensionID,
+		AuthURL:     fullAuthURL,
+		CallbackURL: redirectURI,
+	}
+	pendingAuthRequestsMu.Unlock()
+
+	GoLog("[Extension:%s] PKCE OAuth started: %s\n", r.extensionID, fullAuthURL)
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"authUrl": fullAuthURL,
+		"pkce": map[string]interface{}{
+			"verifier":  verifier,
+			"challenge": challenge,
+			"method":    "S256",
+		},
+	})
+}
+
+// authExchangeCodeWithPKCE exchanges auth code for tokens using PKCE
+// config: { tokenUrl, clientId, redirectUri, code, extraParams }
+// Uses the stored PKCE verifier automatically
+func (r *ExtensionRuntime) authExchangeCodeWithPKCE(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "config object is required",
+		})
+	}
+
+	configObj := call.Arguments[0].Export()
+	config, ok := configObj.(map[string]interface{})
+	if !ok {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "config must be an object",
+		})
+	}
+
+	// Required fields
+	tokenURL, _ := config["tokenUrl"].(string)
+	clientID, _ := config["clientId"].(string)
+	redirectURI, _ := config["redirectUri"].(string)
+	code, _ := config["code"].(string)
+
+	if tokenURL == "" || clientID == "" || code == "" {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "tokenUrl, clientId, and code are required",
+		})
+	}
+
+	// Get stored PKCE verifier
+	extensionAuthStateMu.RLock()
+	state, exists := extensionAuthState[r.extensionID]
+	var verifier string
+	if exists {
+		verifier = state.PKCEVerifier
+	}
+	extensionAuthStateMu.RUnlock()
+
+	if verifier == "" {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "no PKCE verifier found - call generatePKCE or startOAuthWithPKCE first",
+		})
+	}
+
+	// Validate domain
+	if err := r.validateDomain(tokenURL); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Build token request body
+	formData := url.Values{}
+	formData.Set("grant_type", "authorization_code")
+	formData.Set("client_id", clientID)
+	formData.Set("code", code)
+	formData.Set("code_verifier", verifier)
+	if redirectURI != "" {
+		formData.Set("redirect_uri", redirectURI)
+	}
+
+	// Add extra params
+	if extraParams, ok := config["extraParams"].(map[string]interface{}); ok {
+		for k, v := range extraParams {
+			formData.Set(k, fmt.Sprintf("%v", v))
+		}
+	}
+
+	// Make token request
+	req, err := http.NewRequest("POST", tokenURL, strings.NewReader(formData.Encode()))
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("User-Agent", "SpotiFLAC-Extension/1.0")
+
+	resp, err := r.httpClient.Do(req)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+	defer resp.Body.Close()
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Parse response
+	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),
+		})
+	}
+
+	// Check for error in response
+	if errMsg, ok := tokenResp["error"].(string); ok {
+		errDesc, _ := tokenResp["error_description"].(string)
+		return r.vm.ToValue(map[string]interface{}{
+			"success":           false,
+			"error":             errMsg,
+			"error_description": errDesc,
+		})
+	}
+
+	// Extract tokens
+	accessToken, _ := tokenResp["access_token"].(string)
+	refreshToken, _ := tokenResp["refresh_token"].(string)
+	expiresIn, _ := tokenResp["expires_in"].(float64)
+
+	if accessToken == "" {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "no access_token in response",
+			"body":    string(body),
+		})
+	}
+
+	// Store tokens in auth state
+	extensionAuthStateMu.Lock()
+	state, exists = extensionAuthState[r.extensionID]
+	if !exists {
+		state = &ExtensionAuthState{}
+		extensionAuthState[r.extensionID] = state
+	}
+	state.AccessToken = accessToken
+	state.RefreshToken = refreshToken
+	state.IsAuthenticated = true
+	if expiresIn > 0 {
+		state.ExpiresAt = time.Now().Add(time.Duration(expiresIn) * time.Second)
+	}
+	// Clear PKCE after successful exchange
+	state.PKCEVerifier = ""
+	state.PKCEChallenge = ""
+	extensionAuthStateMu.Unlock()
+
+	GoLog("[Extension:%s] PKCE token exchange successful\n", r.extensionID)
+
+	// Return full token response
+	result := map[string]interface{}{
+		"success":       true,
+		"access_token":  accessToken,
+		"refresh_token": refreshToken,
+		"token_type":    tokenResp["token_type"],
+	}
+	if expiresIn > 0 {
+		result["expires_in"] = expiresIn
+	}
+	// Include any additional fields from response
+	if scope, ok := tokenResp["scope"].(string); ok {
+		result["scope"] = scope
+	}
+
+	return r.vm.ToValue(result)
+}

go_backend/extension_runtime_ffmpeg.go

@@ -0,0 +1,204 @@
+// Package gobackend provides FFmpeg API for extension runtime
+package gobackend
+
+import (
+	"fmt"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== FFmpeg API (Post-Processing) ====================
+
+// FFmpegCommand holds a pending FFmpeg command for Flutter to execute
+type FFmpegCommand struct {
+	ExtensionID string
+	Command     string
+	InputPath   string
+	OutputPath  string
+	Completed   bool
+	Success     bool
+	Error       string
+	Output      string
+}
+
+// Global FFmpeg command queue
+var (
+	ffmpegCommands   = make(map[string]*FFmpegCommand)
+	ffmpegCommandsMu sync.RWMutex
+	ffmpegCommandID  int64
+)
+
+// GetPendingFFmpegCommand returns a pending FFmpeg command (called from Flutter)
+func GetPendingFFmpegCommand(commandID string) *FFmpegCommand {
+	ffmpegCommandsMu.RLock()
+	defer ffmpegCommandsMu.RUnlock()
+	return ffmpegCommands[commandID]
+}
+
+// SetFFmpegCommandResult sets the result of an FFmpeg command (called from Flutter)
+func SetFFmpegCommandResult(commandID string, success bool, output, errorMsg string) {
+	ffmpegCommandsMu.Lock()
+	defer ffmpegCommandsMu.Unlock()
+	if cmd, exists := ffmpegCommands[commandID]; exists {
+		cmd.Completed = true
+		cmd.Success = success
+		cmd.Output = output
+		cmd.Error = errorMsg
+	}
+}
+
+// ClearFFmpegCommand removes a completed FFmpeg command
+func ClearFFmpegCommand(commandID string) {
+	ffmpegCommandsMu.Lock()
+	defer ffmpegCommandsMu.Unlock()
+	delete(ffmpegCommands, commandID)
+}
+
+// ffmpegExecute queues an FFmpeg command for execution by Flutter
+func (r *ExtensionRuntime) ffmpegExecute(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "command is required",
+		})
+	}
+
+	command := call.Arguments[0].String()
+
+	// Generate unique command ID
+	ffmpegCommandsMu.Lock()
+	ffmpegCommandID++
+	cmdID := fmt.Sprintf("%s_%d", r.extensionID, ffmpegCommandID)
+	ffmpegCommands[cmdID] = &FFmpegCommand{
+		ExtensionID: r.extensionID,
+		Command:     command,
+		Completed:   false,
+	}
+	ffmpegCommandsMu.Unlock()
+
+	GoLog("[Extension:%s] FFmpeg command queued: %s\n", r.extensionID, cmdID)
+
+	// Wait for completion (with timeout)
+	timeout := 5 * time.Minute
+	start := time.Now()
+	for {
+		ffmpegCommandsMu.RLock()
+		cmd := ffmpegCommands[cmdID]
+		completed := cmd != nil && cmd.Completed
+		ffmpegCommandsMu.RUnlock()
+
+		if completed {
+			ffmpegCommandsMu.RLock()
+			result := map[string]interface{}{
+				"success": cmd.Success,
+				"output":  cmd.Output,
+			}
+			if cmd.Error != "" {
+				result["error"] = cmd.Error
+			}
+			ffmpegCommandsMu.RUnlock()
+
+			// Cleanup
+			ClearFFmpegCommand(cmdID)
+			return r.vm.ToValue(result)
+		}
+
+		if time.Since(start) > timeout {
+			ClearFFmpegCommand(cmdID)
+			return r.vm.ToValue(map[string]interface{}{
+				"success": false,
+				"error":   "FFmpeg command timed out",
+			})
+		}
+
+		time.Sleep(100 * time.Millisecond)
+	}
+}
+
+// ffmpegGetInfo gets audio file information using FFprobe
+func (r *ExtensionRuntime) ffmpegGetInfo(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "file path is required",
+		})
+	}
+
+	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{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success":       true,
+		"bit_depth":     quality.BitDepth,
+		"sample_rate":   quality.SampleRate,
+		"total_samples": quality.TotalSamples,
+		"duration":      float64(quality.TotalSamples) / float64(quality.SampleRate),
+	})
+}
+
+// ffmpegConvert is a helper for common conversion operations
+func (r *ExtensionRuntime) ffmpegConvert(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 2 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "input and output paths are required",
+		})
+	}
+
+	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 {
+			options = opts
+		}
+	}
+
+	// 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)},
+	}
+	return r.ffmpegExecute(execCall)
+}

go_backend/extension_runtime_file.go

@@ -0,0 +1,523 @@
+// Package gobackend provides File API for extension runtime
+package gobackend
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== File API (Sandboxed) ====================
+
+// List of allowed directories for file operations (set by Go backend for download operations)
+var (
+	allowedDownloadDirs   []string
+	allowedDownloadDirsMu sync.RWMutex
+)
+
+// SetAllowedDownloadDirs sets the list of directories where extensions can write files
+// This should be called by the Go backend when setting up download paths
+func SetAllowedDownloadDirs(dirs []string) {
+	allowedDownloadDirsMu.Lock()
+	defer allowedDownloadDirsMu.Unlock()
+	allowedDownloadDirs = dirs
+	GoLog("[Extension] Allowed download directories set: %v\n", dirs)
+}
+
+// AddAllowedDownloadDir adds a directory to the allowed list
+func AddAllowedDownloadDir(dir string) {
+	allowedDownloadDirsMu.Lock()
+	defer allowedDownloadDirsMu.Unlock()
+	absDir, err := filepath.Abs(dir)
+	if err == nil {
+		allowedDownloadDirs = append(allowedDownloadDirs, absDir)
+	}
+}
+
+// isPathInAllowedDirs checks if an absolute path is within any allowed directory
+func isPathInAllowedDirs(absPath string) bool {
+	allowedDownloadDirsMu.RLock()
+	defer allowedDownloadDirsMu.RUnlock()
+
+	for _, allowedDir := range allowedDownloadDirs {
+		if strings.HasPrefix(absPath, allowedDir) {
+			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 (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")
+	}
+
+	// Clean and resolve the path
+	cleanPath := filepath.Clean(path)
+
+	// SECURITY: Block absolute paths by default
+	// Only allow if path is in explicitly allowed download directories
+	if filepath.IsAbs(cleanPath) {
+		absPath, err := filepath.Abs(cleanPath)
+		if err != nil {
+			return "", fmt.Errorf("invalid path: %w", err)
+		}
+
+		// Check if path is in allowed download directories
+		if isPathInAllowedDirs(absPath) {
+			return absPath, nil
+		}
+
+		// Block all other absolute paths
+		return "", fmt.Errorf("file access denied: absolute paths are not allowed. Use relative paths within extension sandbox")
+	}
+
+	// For relative paths, join with data directory (extension's sandbox)
+	fullPath := filepath.Join(r.dataDir, cleanPath)
+
+	// Resolve to absolute path
+	absPath, err := filepath.Abs(fullPath)
+	if err != nil {
+		return "", fmt.Errorf("invalid path: %w", err)
+	}
+
+	// Ensure path is within data directory (prevent path traversal)
+	absDataDir, _ := filepath.Abs(r.dataDir)
+	if !strings.HasPrefix(absPath, absDataDir) {
+		return "", fmt.Errorf("file access denied: path '%s' is outside sandbox", path)
+	}
+
+	return absPath, nil
+}
+
+// fileDownload downloads a file from URL to the specified path
+// Supports progress callback via options.onProgress
+func (r *ExtensionRuntime) fileDownload(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 2 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "URL and output path are required",
+		})
+	}
+
+	urlStr := call.Arguments[0].String()
+	outputPath := call.Arguments[1].String()
+
+	// Validate domain
+	if err := r.validateDomain(urlStr); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Validate output path (allows absolute paths for download queue)
+	fullPath, err := r.validatePath(outputPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Get options if provided
+	var onProgress goja.Callable
+	var headers map[string]string
+	if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) && !goja.IsNull(call.Arguments[2]) {
+		optionsObj := call.Arguments[2].Export()
+		if opts, ok := optionsObj.(map[string]interface{}); ok {
+			// Extract headers
+			if h, ok := opts["headers"].(map[string]interface{}); ok {
+				headers = make(map[string]string)
+				for k, v := range h {
+					headers[k] = fmt.Sprintf("%v", v)
+				}
+			}
+			// Extract onProgress callback
+			if progressVal, ok := opts["onProgress"]; ok {
+				if callable, ok := goja.AssertFunction(r.vm.ToValue(progressVal)); ok {
+					onProgress = callable
+				}
+			}
+		}
+	}
+
+	// Create directory if needed
+	dir := filepath.Dir(fullPath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to create directory: %v", err),
+		})
+	}
+
+	// Create HTTP request
+	req, err := http.NewRequest("GET", urlStr, nil)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Set headers
+	for k, v := range headers {
+		req.Header.Set(k, v)
+	}
+	if req.Header.Get("User-Agent") == "" {
+		req.Header.Set("User-Agent", "SpotiFLAC-Extension/1.0")
+	}
+
+	// Download file
+	resp, err := r.httpClient.Do(req)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("HTTP error: %d", resp.StatusCode),
+		})
+	}
+
+	// Create output file
+	out, err := os.Create(fullPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to create file: %v", err),
+		})
+	}
+	defer out.Close()
+
+	// Get content length for progress
+	contentLength := resp.ContentLength
+
+	// Copy content with progress reporting
+	var written int64
+	buf := make([]byte, 32*1024) // 32KB buffer
+	for {
+		nr, er := resp.Body.Read(buf)
+		if nr > 0 {
+			nw, ew := out.Write(buf[0:nr])
+			if nw < 0 || nr < nw {
+				nw = 0
+				if ew == nil {
+					ew = fmt.Errorf("invalid write result")
+				}
+			}
+			written += int64(nw)
+			if ew != nil {
+				return r.vm.ToValue(map[string]interface{}{
+					"success": false,
+					"error":   fmt.Sprintf("failed to write file: %v", ew),
+				})
+			}
+			if nr != nw {
+				return r.vm.ToValue(map[string]interface{}{
+					"success": false,
+					"error":   "short write",
+				})
+			}
+
+			// Report progress
+			if onProgress != nil && contentLength > 0 {
+				_, _ = onProgress(goja.Undefined(), r.vm.ToValue(written), r.vm.ToValue(contentLength))
+			}
+		}
+		if er != nil {
+			if er != io.EOF {
+				return r.vm.ToValue(map[string]interface{}{
+					"success": false,
+					"error":   fmt.Sprintf("failed to read response: %v", er),
+				})
+			}
+			break
+		}
+	}
+
+	GoLog("[Extension:%s] Downloaded %d bytes to %s\n", r.extensionID, written, fullPath)
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"path":    fullPath,
+		"size":    written,
+	})
+}
+
+// fileExists checks if a file exists in the sandbox
+func (r *ExtensionRuntime) fileExists(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(false)
+	}
+
+	path := call.Arguments[0].String()
+	fullPath, err := r.validatePath(path)
+	if err != nil {
+		return r.vm.ToValue(false)
+	}
+
+	_, err = os.Stat(fullPath)
+	return r.vm.ToValue(err == nil)
+}
+
+// fileDelete deletes a file in the sandbox
+func (r *ExtensionRuntime) fileDelete(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "path is required",
+		})
+	}
+
+	path := call.Arguments[0].String()
+	fullPath, err := r.validatePath(path)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	if err := os.Remove(fullPath); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+	})
+}
+
+// fileRead reads a file from the sandbox
+func (r *ExtensionRuntime) fileRead(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "path is required",
+		})
+	}
+
+	path := call.Arguments[0].String()
+	fullPath, err := r.validatePath(path)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	data, err := os.ReadFile(fullPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"data":    string(data),
+	})
+}
+
+// fileWrite writes data to a file in the sandbox
+func (r *ExtensionRuntime) fileWrite(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 2 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "path and data are required",
+		})
+	}
+
+	path := call.Arguments[0].String()
+	data := call.Arguments[1].String()
+
+	fullPath, err := r.validatePath(path)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Create directory if needed
+	dir := filepath.Dir(fullPath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to create directory: %v", err),
+		})
+	}
+
+	if err := os.WriteFile(fullPath, []byte(data), 0644); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"path":    fullPath,
+	})
+}
+
+// fileCopy copies a file within the sandbox
+func (r *ExtensionRuntime) fileCopy(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 2 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "source and destination paths are required",
+		})
+	}
+
+	srcPath := call.Arguments[0].String()
+	dstPath := call.Arguments[1].String()
+
+	fullSrc, err := r.validatePath(srcPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	fullDst, err := r.validatePath(dstPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Read source file
+	data, err := os.ReadFile(fullSrc)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to read source: %v", err),
+		})
+	}
+
+	// Create destination directory if needed
+	dir := filepath.Dir(fullDst)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to create directory: %v", err),
+		})
+	}
+
+	// Write to destination
+	if err := os.WriteFile(fullDst, data, 0644); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to write destination: %v", err),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"path":    fullDst,
+	})
+}
+
+// fileMove moves/renames a file within the sandbox
+func (r *ExtensionRuntime) fileMove(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 2 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "source and destination paths are required",
+		})
+	}
+
+	srcPath := call.Arguments[0].String()
+	dstPath := call.Arguments[1].String()
+
+	fullSrc, err := r.validatePath(srcPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	fullDst, err := r.validatePath(dstPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	// Create destination directory if needed
+	dir := filepath.Dir(fullDst)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to create directory: %v", err),
+		})
+	}
+
+	if err := os.Rename(fullSrc, fullDst); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   fmt.Sprintf("failed to move file: %v", err),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"path":    fullDst,
+	})
+}
+
+// fileGetSize returns the size of a file in bytes
+func (r *ExtensionRuntime) fileGetSize(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "path is required",
+		})
+	}
+
+	path := call.Arguments[0].String()
+	fullPath, err := r.validatePath(path)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	info, err := os.Stat(fullPath)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"size":    info.Size(),
+	})
+}

go_backend/extension_runtime_http.go

@@ -0,0 +1,505 @@
+// Package gobackend provides HTTP API for extension runtime
+package gobackend
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== 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()
+
+	// Block private/local network access (SSRF protection)
+	if isPrivateIP(domain) {
+		return fmt.Errorf("network access denied: private/local network '%s' not allowed", domain)
+	}
+
+	if !r.manifest.IsDomainAllowed(domain) {
+		return fmt.Errorf("network access denied: domain '%s' not in allowed list", domain)
+	}
+
+	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{}{
+			"error": "URL is required",
+		})
+	}
+
+	urlStr := call.Arguments[0].String()
+
+	// Validate domain
+	if err := r.validateDomain(urlStr); err != nil {
+		GoLog("[Extension:%s] HTTP blocked: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// Get headers if provided
+	headers := make(map[string]string)
+	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 {
+			for k, v := range h {
+				headers[k] = fmt.Sprintf("%v", v)
+			}
+		}
+	}
+
+	// Create request
+	req, err := http.NewRequest("GET", urlStr, nil)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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{}{
+			"error": err.Error(),
+		})
+	}
+	defer resp.Body.Close()
+
+	// Read body
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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
+		}
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"statusCode": resp.StatusCode,
+		"status":     resp.StatusCode, // Alias for convenience
+		"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{}{
+			"error": "URL is required",
+		})
+	}
+
+	urlStr := call.Arguments[0].String()
+
+	// Validate domain
+	if err := r.validateDomain(urlStr); err != nil {
+		GoLog("[Extension:%s] HTTP blocked: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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()
+		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{}{
+					"error": fmt.Sprintf("failed to stringify body: %v", err),
+				})
+			}
+			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()
+		if h, ok := headersObj.(map[string]interface{}); ok {
+			for k, v := range h {
+				headers[k] = fmt.Sprintf("%v", v)
+			}
+		}
+	}
+
+	// Create request
+	req, err := http.NewRequest("POST", urlStr, strings.NewReader(bodyStr))
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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")
+	}
+	if req.Header.Get("Content-Type") == "" {
+		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{}{
+			"error": err.Error(),
+		})
+	}
+	defer resp.Body.Close()
+
+	// Read body
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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
+		}
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"statusCode": resp.StatusCode,
+		"status":     resp.StatusCode, // Alias for convenience
+		"ok":         resp.StatusCode >= 200 && resp.StatusCode < 300,
+		"body":       string(body),
+		"headers":    respHeaders,
+	})
+}
+
+// httpRequest performs a generic HTTP request (GET, POST, PUT, DELETE, etc.)
+// Usage: http.request(url, options) where options = { method, body, headers }
+func (r *ExtensionRuntime) httpRequest(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": "URL is required",
+		})
+	}
+
+	urlStr := call.Arguments[0].String()
+
+	// Validate domain
+	if err := r.validateDomain(urlStr); err != nil {
+		GoLog("[Extension:%s] HTTP blocked: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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{}{
+							"error": fmt.Sprintf("failed to stringify body: %v", err),
+						})
+					}
+					bodyStr = string(jsonBytes)
+				default:
+					bodyStr = fmt.Sprintf("%v", v)
+				}
+			}
+
+			// Get headers
+			if h, ok := opts["headers"].(map[string]interface{}); ok {
+				for k, v := range h {
+					headers[k] = fmt.Sprintf("%v", v)
+				}
+			}
+		}
+	}
+
+	// Create request
+	var reqBody io.Reader
+	if bodyStr != "" {
+		reqBody = strings.NewReader(bodyStr)
+	}
+
+	req, err := http.NewRequest(method, urlStr, reqBody)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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")
+	}
+	if bodyStr != "" && req.Header.Get("Content-Type") == "" {
+		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{}{
+			"error": err.Error(),
+		})
+	}
+	defer resp.Body.Close()
+
+	// Read body
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// 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
+		}
+	}
+
+	// Return response with helper properties
+	return r.vm.ToValue(map[string]interface{}{
+		"statusCode": resp.StatusCode,
+		"status":     resp.StatusCode, // Alias for convenience
+		"ok":         resp.StatusCode >= 200 && resp.StatusCode < 300,
+		"body":       string(body),
+		"headers":    respHeaders,
+	})
+}
+
+// httpPut performs a PUT request (shortcut for http.request with method: "PUT")
+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)
+}
+
+// httpPatch performs a PATCH request (shortcut for http.request with method: "PATCH")
+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{}{
+			"error": "URL is required",
+		})
+	}
+
+	urlStr := call.Arguments[0].String()
+
+	// Validate domain
+	if err := r.validateDomain(urlStr); err != nil {
+		GoLog("[Extension:%s] HTTP blocked: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	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 {
+				for k, v := range h {
+					headers[k] = fmt.Sprintf("%v", v)
+				}
+			}
+		}
+	} 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) {
+			case string:
+				bodyStr = v
+			case map[string]interface{}, []interface{}:
+				jsonBytes, err := json.Marshal(v)
+				if err != nil {
+					return r.vm.ToValue(map[string]interface{}{
+						"error": fmt.Sprintf("failed to stringify body: %v", err),
+					})
+				}
+				bodyStr = string(jsonBytes)
+			default:
+				bodyStr = call.Arguments[1].String()
+			}
+		}
+
+		if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) && !goja.IsNull(call.Arguments[2]) {
+			headersObj := call.Arguments[2].Export()
+			if h, ok := headersObj.(map[string]interface{}); ok {
+				for k, v := range h {
+					headers[k] = fmt.Sprintf("%v", v)
+				}
+			}
+		}
+	}
+
+	// Create request
+	var reqBody io.Reader
+	if bodyStr != "" {
+		reqBody = strings.NewReader(bodyStr)
+	}
+
+	req, err := http.NewRequest(method, urlStr, reqBody)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// Set headers - user headers first
+	for k, v := range headers {
+		req.Header.Set(k, v)
+	}
+	if req.Header.Get("User-Agent") == "" {
+		req.Header.Set("User-Agent", "Spotiflac-Extension/1.0")
+	}
+	if bodyStr != "" && req.Header.Get("Content-Type") == "" {
+		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{}{
+			"error": err.Error(),
+		})
+	}
+	defer resp.Body.Close()
+
+	// Read body
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"error": err.Error(),
+		})
+	}
+
+	// Extract response 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 r.vm.ToValue(map[string]interface{}{
+		"statusCode": resp.StatusCode,
+		"status":     resp.StatusCode,
+		"ok":         resp.StatusCode >= 200 && resp.StatusCode < 300,
+		"body":       string(body),
+		"headers":    respHeaders,
+	})
+}
+
+// httpClearCookies clears all cookies for this extension
+func (r *ExtensionRuntime) httpClearCookies(call goja.FunctionCall) goja.Value {
+	if jar, ok := r.cookieJar.(*simpleCookieJar); ok {
+		jar.mu.Lock()
+		jar.cookies = make(map[string][]*http.Cookie)
+		jar.mu.Unlock()
+		GoLog("[Extension:%s] Cookies cleared\n", r.extensionID)
+		return r.vm.ToValue(true)
+	}
+	return r.vm.ToValue(false)
+}

go_backend/extension_runtime_matching.go

@@ -0,0 +1,151 @@
+// Package gobackend provides Track Matching API for extension runtime
+package gobackend
+
+import (
+	"strings"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== 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)
+	}
+
+	str1 := strings.ToLower(strings.TrimSpace(call.Arguments[0].String()))
+	str2 := strings.ToLower(strings.TrimSpace(call.Arguments[1].String()))
+
+	if str1 == str2 {
+		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)
+	}
+
+	dur1 := int(call.Arguments[0].ToInteger())
+	dur2 := int(call.Arguments[1].ToInteger())
+
+	// Default tolerance: 3 seconds
+	tolerance := 3000 // milliseconds
+	if len(call.Arguments) > 2 && !goja.IsUndefined(call.Arguments[2]) {
+		tolerance = int(call.Arguments[2].ToInteger())
+	}
+
+	diff := dur1 - dur2
+	if diff < 0 {
+		diff = -diff
+	}
+
+	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("")
+	}
+
+	str := call.Arguments[0].String()
+	normalized := normalizeStringForMatching(str)
+	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
+	}
+	if len(s1) == 0 || len(s2) == 0 {
+		return 0.0
+	}
+
+	// Use Levenshtein distance
+	distance := levenshteinDistance(s1, s2)
+	maxLen := len(s1)
+	if len(s2) > maxLen {
+		maxLen = len(s2)
+	}
+
+	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)
+	}
+	if len(s2) == 0 {
+		return len(s1)
+	}
+
+	// Create matrix
+	matrix := make([][]int, len(s1)+1)
+	for i := range matrix {
+		matrix[i] = make([]int, len(s2)+1)
+		matrix[i][0] = i
+	}
+	for j := range matrix[0] {
+		matrix[0][j] = j
+	}
+
+	// Fill matrix
+	for i := 1; i <= len(s1); i++ {
+		for j := 1; j <= len(s2); j++ {
+			cost := 1
+			if s1[i-1] == s2[j-1] {
+				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
+			)
+		}
+	}
+
+	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",
+		" (explicit)", " (clean)", " [explicit]", " [clean]",
+		" (album version)", " (single version)", " (radio edit)",
+		" (feat.", " (ft.", " feat.", " ft.",
+	}
+	for _, suffix := range suffixes {
+		if idx := strings.Index(s, suffix); idx != -1 {
+			s = s[:idx]
+		}
+	}
+
+	// Remove special characters
+	var result strings.Builder
+	for _, r := range s {
+		if (r >= 'a' && r <= 'z') || (r >= '0' && r <= '9') || r == ' ' {
+			result.WriteRune(r)
+		}
+	}
+
+	// Collapse multiple spaces
+	s = strings.Join(strings.Fields(result.String()), " ")
+
+	return strings.TrimSpace(s)
+}

go_backend/extension_runtime_polyfills.go

@@ -0,0 +1,488 @@
+// Package gobackend provides Browser-like Polyfills for extension runtime
+package gobackend
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== Browser-like Polyfills ====================
+// These polyfills make porting browser/Node.js libraries easier
+// without compromising sandbox security
+
+// fetchPolyfill implements browser-compatible fetch() API
+// Returns a Promise-like object with json(), text() methods
+func (r *ExtensionRuntime) fetchPolyfill(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.createFetchError("URL is required")
+	}
+
+	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)
+
+	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)
+			}
+
+			// Body - support string, object (auto-stringify), or nil
+			if bodyArg, ok := opts["body"]; ok && bodyArg != nil {
+				switch v := bodyArg.(type) {
+				case string:
+					bodyStr = v
+				case map[string]interface{}, []interface{}:
+					jsonBytes, err := json.Marshal(v)
+					if err != nil {
+						return r.createFetchError(fmt.Sprintf("failed to stringify body: %v", err))
+					}
+					bodyStr = string(jsonBytes)
+				default:
+					bodyStr = fmt.Sprintf("%v", v)
+				}
+			}
+
+			// Headers
+			if h, ok := opts["headers"]; ok && h != nil {
+				switch hv := h.(type) {
+				case map[string]interface{}:
+					for k, v := range hv {
+						headers[k] = fmt.Sprintf("%v", v)
+					}
+				}
+			}
+		}
+	}
+
+	// Create HTTP request
+	var reqBody io.Reader
+	if bodyStr != "" {
+		reqBody = strings.NewReader(bodyStr)
+	}
+
+	req, err := http.NewRequest(method, urlStr, reqBody)
+	if err != nil {
+		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")
+	}
+	if bodyStr != "" && req.Header.Get("Content-Type") == "" {
+		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 {
+			respHeaders[k] = v[0]
+		} else {
+			respHeaders[k] = v
+		}
+	}
+
+	// Create Response object (browser-compatible)
+	responseObj := r.vm.NewObject()
+	responseObj.Set("ok", resp.StatusCode >= 200 && resp.StatusCode < 300)
+	responseObj.Set("status", resp.StatusCode)
+	responseObj.Set("statusText", http.StatusText(resp.StatusCode))
+	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 {
+			GoLog("[Extension:%s] fetch json() parse error: %v\n", r.extensionID, err)
+			return goja.Undefined()
+		}
+		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)
+		}
+		return r.vm.ToValue(byteArray)
+	})
+
+	return responseObj
+}
+
+// createFetchError creates a fetch error response
+func (r *ExtensionRuntime) createFetchError(message string) goja.Value {
+	errorObj := r.vm.NewObject()
+	errorObj.Set("ok", false)
+	errorObj.Set("status", 0)
+	errorObj.Set("statusText", "Network Error")
+	errorObj.Set("error", message)
+	errorObj.Set("text", func(call goja.FunctionCall) goja.Value {
+		return r.vm.ToValue("")
+	})
+	errorObj.Set("json", func(call goja.FunctionCall) goja.Value {
+		return goja.Undefined()
+	})
+	return errorObj
+}
+
+// atobPolyfill implements browser atob() - decode base64 to string
+func (r *ExtensionRuntime) atobPolyfill(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue("")
+	}
+	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)
+			return r.vm.ToValue("")
+		}
+	}
+	return r.vm.ToValue(string(decoded))
+}
+
+// btoaPolyfill implements browser btoa() - encode string to base64
+func (r *ExtensionRuntime) btoaPolyfill(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return r.vm.ToValue("")
+	}
+	input := call.Arguments[0].String()
+	return r.vm.ToValue(base64.StdEncoding.EncodeToString([]byte(input)))
+}
+
+// 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{})
+			}
+			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)
+			}
+			return vm.ToValue(result)
+		})
+
+		// encodeInto() method
+		encoder.Set("encodeInto", func(call goja.FunctionCall) goja.Value {
+			// Simplified implementation
+			if len(call.Arguments) < 2 {
+				return vm.ToValue(map[string]interface{}{"read": 0, "written": 0})
+			}
+			input := call.Arguments[0].String()
+			return vm.ToValue(map[string]interface{}{
+				"read":    len(input),
+				"written": len([]byte(input)),
+			})
+		})
+
+		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()
+		}
+		decoder.Set("encoding", encoding)
+		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
+
+			switch v := input.(type) {
+			case []byte:
+				bytes = v
+			case []interface{}:
+				bytes = make([]byte, len(v))
+				for i, val := range v {
+					switch n := val.(type) {
+					case int64:
+						bytes[i] = byte(n)
+					case float64:
+						bytes[i] = byte(n)
+					case int:
+						bytes[i] = byte(n)
+					}
+				}
+			case string:
+				// Already a string, just return it
+				return vm.ToValue(v)
+			default:
+				return vm.ToValue("")
+			}
+
+			return vm.ToValue(string(bytes))
+		})
+
+		return nil
+	})
+}
+
+// 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
+
+		if len(call.Arguments) < 1 {
+			urlObj.Set("href", "")
+			return nil
+		}
+
+		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)
+			if err == nil {
+				relURL, err := url.Parse(urlStr)
+				if err == nil {
+					urlStr = baseURL.ResolveReference(relURL).String()
+				}
+			}
+		}
+
+		parsed, err := url.Parse(urlStr)
+		if err != nil {
+			urlObj.Set("href", urlStr)
+			return nil
+		}
+
+		// Set URL properties
+		urlObj.Set("href", parsed.String())
+		urlObj.Set("protocol", parsed.Scheme+":")
+		urlObj.Set("host", parsed.Host)
+		urlObj.Set("hostname", parsed.Hostname())
+		urlObj.Set("port", parsed.Port())
+		urlObj.Set("pathname", parsed.Path)
+		urlObj.Set("search", "")
+		if parsed.RawQuery != "" {
+			urlObj.Set("search", "?"+parsed.RawQuery)
+		}
+		urlObj.Set("hash", "")
+		if parsed.Fragment != "" {
+			urlObj.Set("hash", "#"+parsed.Fragment)
+		}
+		urlObj.Set("origin", parsed.Scheme+"://"+parsed.Host)
+		urlObj.Set("username", parsed.User.Username())
+		password, _ := parsed.User.Password()
+		urlObj.Set("password", password)
+
+		// searchParams object
+		searchParams := vm.NewObject()
+		queryValues := parsed.Query()
+
+		searchParams.Set("get", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) < 1 {
+				return goja.Null()
+			}
+			key := call.Arguments[0].String()
+			if val := queryValues.Get(key); val != "" {
+				return vm.ToValue(val)
+			}
+			return goja.Null()
+		})
+
+		searchParams.Set("getAll", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) < 1 {
+				return vm.ToValue([]string{})
+			}
+			key := call.Arguments[0].String()
+			return vm.ToValue(queryValues[key])
+		})
+
+		searchParams.Set("has", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) < 1 {
+				return vm.ToValue(false)
+			}
+			key := call.Arguments[0].String()
+			return vm.ToValue(queryValues.Has(key))
+		})
+
+		searchParams.Set("toString", func(call goja.FunctionCall) goja.Value {
+			return vm.ToValue(queryValues.Encode())
+		})
+
+		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())
+		})
+
+		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{}:
+				for k, val := range v {
+					values.Set(k, fmt.Sprintf("%v", val))
+				}
+			}
+		}
+
+		paramsObj.Set("append", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) >= 2 {
+				values.Add(call.Arguments[0].String(), call.Arguments[1].String())
+			}
+			return goja.Undefined()
+		})
+
+		paramsObj.Set("delete", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) >= 1 {
+				values.Del(call.Arguments[0].String())
+			}
+			return goja.Undefined()
+		})
+
+		paramsObj.Set("get", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) < 1 {
+				return goja.Null()
+			}
+			if val := values.Get(call.Arguments[0].String()); val != "" {
+				return vm.ToValue(val)
+			}
+			return goja.Null()
+		})
+
+		paramsObj.Set("getAll", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) < 1 {
+				return vm.ToValue([]string{})
+			}
+			return vm.ToValue(values[call.Arguments[0].String()])
+		})
+
+		paramsObj.Set("has", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) < 1 {
+				return vm.ToValue(false)
+			}
+			return vm.ToValue(values.Has(call.Arguments[0].String()))
+		})
+
+		paramsObj.Set("set", func(call goja.FunctionCall) goja.Value {
+			if len(call.Arguments) >= 2 {
+				values.Set(call.Arguments[0].String(), call.Arguments[1].String())
+			}
+			return goja.Undefined()
+		})
+
+		paramsObj.Set("toString", func(call goja.FunctionCall) goja.Value {
+			return vm.ToValue(values.Encode())
+		})
+
+		return nil
+	})
+}
+
+// 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 = {
+				parse: function(text) {
+					return utils.parseJSON(text);
+				},
+				stringify: function(value, replacer, space) {
+					return utils.stringifyJSON(value);
+				}
+			};
+		}
+	`
+	_, _ = vm.RunString(jsonScript)
+}

go_backend/extension_runtime_storage.go

@@ -0,0 +1,381 @@
+// Package gobackend provides Storage and Credentials API for extension runtime
+package gobackend
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"crypto/sha256"
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== 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)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return make(map[string]interface{}), nil
+		}
+		return nil, err
+	}
+
+	var storage map[string]interface{}
+	if err := json.Unmarshal(data, &storage); err != nil {
+		return nil, err
+	}
+
+	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, "", "  ")
+	if err != nil {
+		return err
+	}
+
+	return os.WriteFile(storagePath, data, 0644)
+}
+
+// storageGet retrieves a value from storage
+func (r *ExtensionRuntime) storageGet(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return goja.Undefined()
+	}
+
+	key := call.Arguments[0].String()
+
+	storage, err := r.loadStorage()
+	if err != nil {
+		GoLog("[Extension:%s] Storage load error: %v\n", r.extensionID, err)
+		return goja.Undefined()
+	}
+
+	value, exists := storage[key]
+	if !exists {
+		// Return default value if provided
+		if len(call.Arguments) > 1 {
+			return call.Arguments[1]
+		}
+		return goja.Undefined()
+	}
+
+	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)
+	}
+
+	key := call.Arguments[0].String()
+	value := call.Arguments[1].Export()
+
+	storage, err := r.loadStorage()
+	if err != nil {
+		GoLog("[Extension:%s] Storage load error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(false)
+	}
+
+	storage[key] = value
+
+	if err := r.saveStorage(storage); err != nil {
+		GoLog("[Extension:%s] Storage save error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(false)
+	}
+
+	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)
+	}
+
+	key := call.Arguments[0].String()
+
+	storage, err := r.loadStorage()
+	if err != nil {
+		GoLog("[Extension:%s] Storage load error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(false)
+	}
+
+	delete(storage, key)
+
+	if err := r.saveStorage(storage); err != nil {
+		GoLog("[Extension:%s] Storage save error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(false)
+	}
+
+	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()
+
+	// Try to read existing salt
+	salt, err := os.ReadFile(saltPath)
+	if err == nil && len(salt) == 32 {
+		return salt, nil
+	}
+
+	// Generate new random salt (32 bytes)
+	salt = make([]byte, 32)
+	if _, err := io.ReadFull(rand.Reader, salt); err != nil {
+		return nil, fmt.Errorf("failed to generate salt: %w", err)
+	}
+
+	// Save salt to file
+	if err := os.WriteFile(saltPath, salt, 0600); err != nil {
+		return nil, fmt.Errorf("failed to save salt: %w", err)
+	}
+
+	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)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return make(map[string]interface{}), nil
+		}
+		return nil, err
+	}
+
+	// Decrypt the data
+	key, err := r.getEncryptionKey()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get encryption key: %w", err)
+	}
+	decrypted, err := decryptAES(data, key)
+	if err != nil {
+		return nil, fmt.Errorf("failed to decrypt credentials: %w", err)
+	}
+
+	var creds map[string]interface{}
+	if err := json.Unmarshal(decrypted, &creds); err != nil {
+		return nil, err
+	}
+
+	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 {
+		return err
+	}
+
+	// Encrypt the data
+	key, err := r.getEncryptionKey()
+	if err != nil {
+		return fmt.Errorf("failed to get encryption key: %w", err)
+	}
+	encrypted, err := encryptAES(data, key)
+	if err != nil {
+		return fmt.Errorf("failed to encrypt credentials: %w", err)
+	}
+
+	credPath := r.getCredentialsPath()
+	return os.WriteFile(credPath, encrypted, 0600) // Restrictive permissions
+}
+
+// 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{}{
+			"success": false,
+			"error":   "key and value are required",
+		})
+	}
+
+	key := call.Arguments[0].String()
+	value := call.Arguments[1].Export()
+
+	creds, err := r.loadCredentials()
+	if err != nil {
+		GoLog("[Extension:%s] Credentials load error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	creds[key] = value
+
+	if err := r.saveCredentials(creds); err != nil {
+		GoLog("[Extension:%s] Credentials save error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+	})
+}
+
+// credentialsGet retrieves a decrypted credential
+func (r *ExtensionRuntime) credentialsGet(call goja.FunctionCall) goja.Value {
+	if len(call.Arguments) < 1 {
+		return goja.Undefined()
+	}
+
+	key := call.Arguments[0].String()
+
+	creds, err := r.loadCredentials()
+	if err != nil {
+		GoLog("[Extension:%s] Credentials load error: %v\n", r.extensionID, err)
+		return goja.Undefined()
+	}
+
+	value, exists := creds[key]
+	if !exists {
+		// Return default value if provided
+		if len(call.Arguments) > 1 {
+			return call.Arguments[1]
+		}
+		return goja.Undefined()
+	}
+
+	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)
+	}
+
+	key := call.Arguments[0].String()
+
+	creds, err := r.loadCredentials()
+	if err != nil {
+		GoLog("[Extension:%s] Credentials load error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(false)
+	}
+
+	delete(creds, key)
+
+	if err := r.saveCredentials(creds); err != nil {
+		GoLog("[Extension:%s] Credentials save error: %v\n", r.extensionID, err)
+		return r.vm.ToValue(false)
+	}
+
+	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)
+	}
+
+	key := call.Arguments[0].String()
+
+	creds, err := r.loadCredentials()
+	if err != nil {
+		return r.vm.ToValue(false)
+	}
+
+	_, exists := creds[key]
+	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 {
+		return nil, err
+	}
+
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return nil, err
+	}
+
+	nonce := make([]byte, gcm.NonceSize())
+	if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
+		return nil, err
+	}
+
+	ciphertext := gcm.Seal(nonce, nonce, plaintext, nil)
+	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 {
+		return nil, err
+	}
+
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return nil, err
+	}
+
+	nonceSize := gcm.NonceSize()
+	if len(ciphertext) < nonceSize {
+		return nil, fmt.Errorf("ciphertext too short")
+	}
+
+	nonce, ciphertext := ciphertext[:nonceSize], ciphertext[nonceSize:]
+	plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	return plaintext, nil
+}

go_backend/extension_runtime_utils.go

@@ -0,0 +1,372 @@
+// Package gobackend provides Utility functions for extension runtime
+package gobackend
+
+import (
+	"crypto/hmac"
+	"crypto/md5"
+	"crypto/rand"
+	"crypto/sha1"
+	"crypto/sha256"
+	"encoding/base64"
+	"encoding/hex"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"github.com/dop251/goja"
+)
+
+// ==================== 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("")
+	}
+	input := call.Arguments[0].String()
+	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("")
+	}
+	input := call.Arguments[0].String()
+	decoded, err := base64.StdEncoding.DecodeString(input)
+	if err != nil {
+		return r.vm.ToValue("")
+	}
+	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("")
+	}
+	input := call.Arguments[0].String()
+	hash := md5.Sum([]byte(input))
+	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("")
+	}
+	input := call.Arguments[0].String()
+	hash := sha256.Sum256([]byte(input))
+	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("")
+	}
+	message := call.Arguments[0].String()
+	key := call.Arguments[1].String()
+
+	mac := hmac.New(sha256.New, []byte(key))
+	mac.Write([]byte(message))
+	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("")
+	}
+	message := call.Arguments[0].String()
+	key := call.Arguments[1].String()
+
+	mac := hmac.New(sha256.New, []byte(key))
+	mac.Write([]byte(message))
+	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{})
+	}
+
+	// Get key - can be string or array of bytes
+	var keyBytes []byte
+	keyArg := call.Arguments[0].Export()
+	switch k := keyArg.(type) {
+	case string:
+		keyBytes = []byte(k)
+	case []interface{}:
+		keyBytes = make([]byte, len(k))
+		for i, v := range k {
+			if num, ok := v.(int64); ok {
+				keyBytes[i] = byte(num)
+			} else if num, ok := v.(float64); ok {
+				keyBytes[i] = byte(int(num))
+			}
+		}
+	default:
+		return r.vm.ToValue([]byte{})
+	}
+
+	// Get message - can be string or array of bytes
+	var msgBytes []byte
+	msgArg := call.Arguments[1].Export()
+	switch m := msgArg.(type) {
+	case string:
+		msgBytes = []byte(m)
+	case []interface{}:
+		msgBytes = make([]byte, len(m))
+		for i, v := range m {
+			if num, ok := v.(int64); ok {
+				msgBytes[i] = byte(num)
+			} else if num, ok := v.(float64); ok {
+				msgBytes[i] = byte(int(num))
+			}
+		}
+	default:
+		return r.vm.ToValue([]byte{})
+	}
+
+	mac := hmac.New(sha1.New, keyBytes)
+	mac.Write(msgBytes)
+	result := mac.Sum(nil)
+
+	// Convert to array of numbers for JavaScript
+	jsArray := make([]interface{}, len(result))
+	for i, b := range result {
+		jsArray[i] = int(b)
+	}
+	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()
+	}
+	input := call.Arguments[0].String()
+
+	var result interface{}
+	if err := json.Unmarshal([]byte(input), &result); err != nil {
+		GoLog("[Extension:%s] JSON parse error: %v\n", r.extensionID, err)
+		return goja.Undefined()
+	}
+
+	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("")
+	}
+	input := call.Arguments[0].Export()
+
+	data, err := json.Marshal(input)
+	if err != nil {
+		GoLog("[Extension:%s] JSON stringify error: %v\n", r.extensionID, err)
+		return r.vm.ToValue("")
+	}
+
+	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{}{
+			"success": false,
+			"error":   "plaintext and key are required",
+		})
+	}
+
+	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[:])
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"data":    base64.StdEncoding.EncodeToString(encrypted),
+	})
+}
+
+// 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{}{
+			"success": false,
+			"error":   "ciphertext and key are required",
+		})
+	}
+
+	ciphertextB64 := call.Arguments[0].String()
+	keyStr := call.Arguments[1].String()
+
+	ciphertext, err := base64.StdEncoding.DecodeString(ciphertextB64)
+	if err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   "invalid base64 ciphertext",
+		})
+	}
+
+	// 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(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"data":    string(decrypted),
+	})
+}
+
+// cryptoGenerateKey generates a random encryption key
+func (r *ExtensionRuntime) cryptoGenerateKey(call goja.FunctionCall) goja.Value {
+	length := 32 // Default 256-bit key
+	if len(call.Arguments) > 0 && !goja.IsUndefined(call.Arguments[0]) {
+		if l, ok := call.Arguments[0].Export().(float64); ok {
+			length = int(l)
+		}
+	}
+
+	key := make([]byte, length)
+	if _, err := rand.Read(key); err != nil {
+		return r.vm.ToValue(map[string]interface{}{
+			"success": false,
+			"error":   err.Error(),
+		})
+	}
+
+	return r.vm.ToValue(map[string]interface{}{
+		"success": true,
+		"key":     base64.StdEncoding.EncodeToString(key),
+		"hex":     hex.EncodeToString(key),
+	})
+}
+
+// ==================== 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)
+	return goja.Undefined()
+}
+
+func (r *ExtensionRuntime) logInfo(call goja.FunctionCall) goja.Value {
+	msg := r.formatLogArgs(call.Arguments)
+	GoLog("[Extension:%s:INFO] %s\n", r.extensionID, msg)
+	return goja.Undefined()
+}
+
+func (r *ExtensionRuntime) logWarn(call goja.FunctionCall) goja.Value {
+	msg := r.formatLogArgs(call.Arguments)
+	GoLog("[Extension:%s:WARN] %s\n", r.extensionID, msg)
+	return goja.Undefined()
+}
+
+func (r *ExtensionRuntime) logError(call goja.FunctionCall) goja.Value {
+	msg := r.formatLogArgs(call.Arguments)
+	GoLog("[Extension:%s:ERROR] %s\n", r.extensionID, msg)
+	return goja.Undefined()
+}
+
+func (r *ExtensionRuntime) formatLogArgs(args []goja.Value) string {
+	parts := make([]string, len(args))
+	for i, arg := range args {
+		parts[i] = fmt.Sprintf("%v", arg.Export())
+	}
+	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("")
+	}
+	input := call.Arguments[0].String()
+	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) {
+		gobackendObj = vm.NewObject()
+		vm.Set("gobackend", gobackendObj)
+	}
+
+	obj := gobackendObj.(*goja.Object)
+
+	// Expose sanitizeFilename
+	obj.Set("sanitizeFilename", func(call goja.FunctionCall) goja.Value {
+		if len(call.Arguments) < 1 {
+			return vm.ToValue("")
+		}
+		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{}{
+				"error": "file path is required",
+			})
+		}
+
+		filePath := call.Arguments[0].String()
+		quality, err := GetAudioQuality(filePath)
+		if err != nil {
+			return vm.ToValue(map[string]interface{}{
+				"error": err.Error(),
+			})
+		}
+
+		return vm.ToValue(map[string]interface{}{
+			"bitDepth":     quality.BitDepth,
+			"sampleRate":   quality.SampleRate,
+			"totalSamples": quality.TotalSamples,
+		})
+	})
+
+	// Expose buildFilename
+	obj.Set("buildFilename", func(call goja.FunctionCall) goja.Value {
+		if len(call.Arguments) < 2 {
+			return vm.ToValue("")
+		}
+
+		template := call.Arguments[0].String()
+		metadataObj := call.Arguments[1].Export()
+
+		metadata, ok := metadataObj.(map[string]interface{})
+		if !ok {
+			return vm.ToValue("")
+		}
+
+		return vm.ToValue(buildFilenameFromTemplate(template, metadata))
+	})
+}

go_backend/extension_settings.go

@@ -0,0 +1,221 @@
+// Package gobackend provides extension settings storage
+package gobackend
+
+import (
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"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{
+			settings: make(map[string]map[string]interface{}),
+		}
+	})
+	return globalSettingsStore
+}
+
+// SetDataDir sets the data directory for settings storage
+func (s *ExtensionSettingsStore) SetDataDir(dataDir string) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	s.dataDir = dataDir
+	if err := os.MkdirAll(dataDir, 0755); err != nil {
+		return fmt.Errorf("failed to create settings directory: %w", err)
+	}
+
+	// Load all existing settings
+	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 {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		return err
+	}
+
+	for _, entry := range entries {
+		if entry.IsDir() {
+			extensionID := entry.Name()
+			settings, err := s.loadSettings(extensionID)
+			if err != nil {
+				GoLog("[ExtensionSettings] Failed to load settings for %s: %v\n", extensionID, err)
+				continue
+			}
+			s.settings[extensionID] = settings
+		}
+	}
+
+	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)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return make(map[string]interface{}), nil
+		}
+		return nil, err
+	}
+
+	var settings map[string]interface{}
+	if err := json.Unmarshal(data, &settings); err != nil {
+		return nil, err
+	}
+
+	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)
+
+	// Create directory if needed
+	dir := filepath.Dir(settingsPath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return err
+	}
+
+	data, err := json.MarshalIndent(settings, "", "  ")
+	if err != nil {
+		return err
+	}
+
+	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()
+
+	extSettings, exists := s.settings[extensionID]
+	if !exists {
+		return nil, fmt.Errorf("extension '%s' settings not found", extensionID)
+	}
+
+	value, exists := extSettings[key]
+	if !exists {
+		return nil, fmt.Errorf("setting '%s' not found for extension '%s'", key, extensionID)
+	}
+	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()
+
+	extSettings, exists := s.settings[extensionID]
+	if !exists {
+		return make(map[string]interface{})
+	}
+
+	// Return a copy
+	result := make(map[string]interface{})
+	for k, v := range extSettings {
+		result[k] = v
+	}
+	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()
+
+	if _, exists := s.settings[extensionID]; !exists {
+		s.settings[extensionID] = make(map[string]interface{})
+	}
+
+	s.settings[extensionID][key] = value
+
+	// Persist to disk
+	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()
+
+	extSettings, exists := s.settings[extensionID]
+	if !exists {
+		return nil
+	}
+
+	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()
+
+	delete(s.settings, extensionID)
+
+	// Remove settings file
+	settingsPath := s.getSettingsPath(extensionID)
+	if err := os.Remove(settingsPath); err != nil && !os.IsNotExist(err) {
+		return err
+	}
+
+	return nil
+}
+
+// GetAllExtensionSettings returns settings for all extensions as JSON
+func (s *ExtensionSettingsStore) GetAllExtensionSettingsJSON() (string, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	data, err := json.Marshal(s.settings)
+	if err != nil {
+		return "", err
+	}
+
+	return string(data), nil
+}

go_backend/extension_store.go

@@ -0,0 +1,453 @@
+package gobackend
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path/filepath"
+	"sync"
+	"time"
+)
+
+// Extension categories
+const (
+	CategoryMetadata    = "metadata"
+	CategoryDownload    = "download"
+	CategoryUtility     = "utility"
+	CategoryLyrics      = "lyrics"
+	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"`
+	// Alternative camelCase fields (for flexibility)
+	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
+	}
+	if e.DisplayNameAlt != "" {
+		return e.DisplayNameAlt
+	}
+	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
+	}
+	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
+	}
+	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
+	}
+	return e.MinAppVersionAlt
+}
+
+// StoreRegistry represents the extension registry
+type StoreRegistry struct {
+	Version    int              `json:"version"`
+	UpdatedAt  string           `json:"updated_at"`
+	Extensions []StoreExtension `json:"extensions"`
+}
+
+// StoreExtensionResponse is the normalized response sent to Flutter
+type StoreExtensionResponse struct {
+	ID               string   `json:"id"`
+	Name             string   `json:"name"`
+	DisplayName      string   `json:"display_name"`
+	Version          string   `json:"version"`
+	Author           string   `json:"author"`
+	Description      string   `json:"description"`
+	DownloadURL      string   `json:"download_url"`
+	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"`
+	IsInstalled      bool     `json:"is_installed"`
+	InstalledVersion string   `json:"installed_version,omitempty"`
+	HasUpdate        bool     `json:"has_update"`
+}
+
+// ToResponse converts StoreExtension to normalized response
+func (e *StoreExtension) ToResponse() StoreExtensionResponse {
+	return StoreExtensionResponse{
+		ID:            e.ID,
+		Name:          e.Name,
+		DisplayName:   e.getDisplayName(),
+		Version:       e.Version,
+		Author:        e.Author,
+		Description:   e.Description,
+		DownloadURL:   e.getDownloadURL(),
+		IconURL:       e.getIconURL(),
+		Category:      e.Category,
+		Tags:          e.Tags,
+		Downloads:     e.Downloads,
+		UpdatedAt:     e.UpdatedAt,
+		MinAppVersion: e.getMinAppVersion(),
+	}
+}
+
+// ExtensionStore manages the extension store
+type ExtensionStore struct {
+	registryURL string
+	cacheDir    string
+	cache       *StoreRegistry
+	cacheMu     sync.RWMutex
+	cacheTime   time.Time
+	cacheTTL    time.Duration
+}
+
+var (
+	extensionStore   *ExtensionStore
+	extensionStoreMu sync.Mutex
+)
+
+const (
+	defaultRegistryURL = "https://raw.githubusercontent.com/zarzet/SpotiFLAC-Extension/main/registry.json"
+	cacheTTL           = 30 * time.Minute
+	cacheFileName      = "store_cache.json"
+)
+
+// InitExtensionStore initializes the extension store
+func InitExtensionStore(cacheDir string) *ExtensionStore {
+	extensionStoreMu.Lock()
+	defer extensionStoreMu.Unlock()
+
+	if extensionStore == nil {
+		extensionStore = &ExtensionStore{
+			registryURL: defaultRegistryURL,
+			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
+	}
+
+	cachePath := filepath.Join(s.cacheDir, cacheFileName)
+	data, err := os.ReadFile(cachePath)
+	if err != nil {
+		return
+	}
+
+	var cacheData struct {
+		Registry  StoreRegistry `json:"registry"`
+		CacheTime int64         `json:"cache_time"`
+	}
+
+	if err := json.Unmarshal(data, &cacheData); err != nil {
+		return
+	}
+
+	s.cache = &cacheData.Registry
+	s.cacheTime = time.Unix(cacheData.CacheTime, 0)
+	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
+	}
+
+	cacheData := struct {
+		Registry  StoreRegistry `json:"registry"`
+		CacheTime int64         `json:"cache_time"`
+	}{
+		Registry:  *s.cache,
+		CacheTime: s.cacheTime.Unix(),
+	}
+
+	data, err := json.Marshal(cacheData)
+	if err != nil {
+		return
+	}
+
+	cachePath := filepath.Join(s.cacheDir, cacheFileName)
+	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
+	}
+
+	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
+		}
+		return nil, fmt.Errorf("failed to fetch registry: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		if s.cache != nil {
+			LogWarn("ExtensionStore", "HTTP %d, using cached registry", resp.StatusCode)
+			return s.cache, nil
+		}
+		return nil, fmt.Errorf("registry returned HTTP %d", resp.StatusCode)
+	}
+
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read registry: %w", err)
+	}
+
+	var registry StoreRegistry
+	if err := json.Unmarshal(body, &registry); err != nil {
+		return nil, fmt.Errorf("failed to parse registry: %w", err)
+	}
+
+	s.cache = &registry
+	s.cacheTime = time.Now()
+	s.saveDiskCache()
+
+	LogInfo("ExtensionStore", "Fetched %d extensions from registry", len(registry.Extensions))
+	return &registry, nil
+}
+
+// GetExtensionsWithStatus returns extensions with installation status
+func (s *ExtensionStore) GetExtensionsWithStatus() ([]StoreExtensionResponse, error) {
+	registry, err := s.FetchRegistry(false)
+	if err != nil {
+		return nil, err
+	}
+
+	manager := GetExtensionManager()
+	installed := make(map[string]string) // id -> version
+
+	if manager != nil {
+		for _, ext := range manager.GetAllExtensions() {
+			installed[ext.ID] = ext.Manifest.Version
+		}
+	}
+
+	result := make([]StoreExtensionResponse, len(registry.Extensions))
+	for i, ext := range registry.Extensions {
+		resp := ext.ToResponse()
+
+		if installedVersion, ok := installed[ext.ID]; ok {
+			resp.IsInstalled = true
+			resp.InstalledVersion = installedVersion
+			resp.HasUpdate = compareVersions(ext.Version, installedVersion) > 0
+		}
+
+		result[i] = resp
+	}
+
+	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 {
+		return err
+	}
+
+	var ext *StoreExtension
+	for _, e := range registry.Extensions {
+		if e.ID == extensionID {
+			ext = &e
+			break
+		}
+	}
+
+	if ext == nil {
+		return fmt.Errorf("extension %s not found in store", extensionID)
+	}
+
+	LogInfo("ExtensionStore", "Downloading %s from %s", ext.getDisplayName(), ext.getDownloadURL())
+
+	client := &http.Client{Timeout: 5 * time.Minute}
+	resp, err := client.Get(ext.getDownloadURL())
+	if err != nil {
+		return fmt.Errorf("failed to download: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("download returned HTTP %d", resp.StatusCode)
+	}
+
+	// Create destination file
+	out, err := os.Create(destPath)
+	if err != nil {
+		return fmt.Errorf("failed to create file: %w", err)
+	}
+	defer out.Close()
+
+	_, err = io.Copy(out, resp.Body)
+	if err != nil {
+		os.Remove(destPath)
+		return fmt.Errorf("failed to write file: %w", err)
+	}
+
+	LogInfo("ExtensionStore", "Downloaded %s to %s", ext.getDisplayName(), destPath)
+	return nil
+}
+
+// GetCategories returns all available categories
+func (s *ExtensionStore) GetCategories() []string {
+	return []string{
+		CategoryMetadata,
+		CategoryDownload,
+		CategoryUtility,
+		CategoryLyrics,
+		CategoryIntegration,
+	}
+}
+
+// SearchExtensions searches extensions by query
+func (s *ExtensionStore) SearchExtensions(query string, category string) ([]StoreExtensionResponse, error) {
+	extensions, err := s.GetExtensionsWithStatus()
+	if err != nil {
+		return nil, err
+	}
+
+	if query == "" && category == "" {
+		return extensions, nil
+	}
+
+	var result []StoreExtensionResponse
+	queryLower := toLower(query)
+
+	for _, ext := range extensions {
+		// Filter by category
+		if category != "" && ext.Category != category {
+			continue
+		}
+
+		// Filter by query
+		if query != "" {
+			if !containsIgnoreCase(ext.Name, queryLower) &&
+				!containsIgnoreCase(ext.DisplayName, queryLower) &&
+				!containsIgnoreCase(ext.Description, queryLower) &&
+				!containsIgnoreCase(ext.Author, queryLower) {
+				// Check tags
+				found := false
+				for _, tag := range ext.Tags {
+					if containsIgnoreCase(tag, queryLower) {
+						found = true
+						break
+					}
+				}
+				if !found {
+					continue
+				}
+			}
+		}
+
+		result = append(result, ext)
+	}
+
+	return result, nil
+}
+
+// ClearCache clears the in-memory and disk cache
+func (s *ExtensionStore) ClearCache() {
+	s.cacheMu.Lock()
+	defer s.cacheMu.Unlock()
+
+	s.cache = nil
+	s.cacheTime = time.Time{}
+
+	if s.cacheDir != "" {
+		cachePath := filepath.Join(s.cacheDir, cacheFileName)
+		os.Remove(cachePath)
+	}
+
+	LogInfo("ExtensionStore", "Cache cleared")
+}
+
+// Helper: case-insensitive contains
+func containsIgnoreCase(s, substr string) bool {
+	return containsStr(toLower(s), substr)
+}
+
+func toLower(s string) string {
+	result := make([]byte, len(s))
+	for i := 0; i < len(s); i++ {
+		c := s[i]
+		if c >= 'A' && c <= 'Z' {
+			c += 'a' - 'A'
+		}
+		result[i] = c
+	}
+	return string(result)
+}
+
+func containsStr(s, substr string) bool {
+	return len(substr) == 0 || (len(s) >= len(substr) && findSubstring(s, substr) >= 0)
+}
+
+func findSubstring(s, substr string) int {
+	for i := 0; i <= len(s)-len(substr); i++ {
+		if s[i:i+len(substr)] == substr {
+			return i
+		}
+	}
+	return -1
+}

go_backend/extension_test.go

@@ -0,0 +1,329 @@
+package gobackend
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/dop251/goja"
+)
+
+func TestParseManifest_Valid(t *testing.T) {
+	validManifest := `{
+		"name": "test-provider",
+		"displayName": "Test Provider",
+		"version": "1.0.0",
+		"author": "Test Author",
+		"description": "A test extension",
+		"type": ["metadata_provider"],
+		"permissions": {
+			"network": ["api.test.com"],
+			"storage": true
+		}
+	}`
+
+	manifest, err := ParseManifest([]byte(validManifest))
+	if err != nil {
+		t.Fatalf("Expected valid manifest to parse, got error: %v", err)
+	}
+
+	if manifest.Name != "test-provider" {
+		t.Errorf("Expected name 'test-provider', got '%s'", manifest.Name)
+	}
+
+	if manifest.Version != "1.0.0" {
+		t.Errorf("Expected version '1.0.0', got '%s'", manifest.Version)
+	}
+
+	if !manifest.IsMetadataProvider() {
+		t.Error("Expected IsMetadataProvider() to return true")
+	}
+
+	if manifest.IsDownloadProvider() {
+		t.Error("Expected IsDownloadProvider() to return false")
+	}
+}
+
+func TestParseManifest_MissingName(t *testing.T) {
+	invalidManifest := `{
+		"version": "1.0.0",
+		"author": "Test Author",
+		"description": "A test extension",
+		"type": ["metadata_provider"]
+	}`
+
+	_, err := ParseManifest([]byte(invalidManifest))
+	if err == nil {
+		t.Fatal("Expected error for missing name")
+	}
+}
+
+func TestParseManifest_MissingType(t *testing.T) {
+	invalidManifest := `{
+		"name": "test-provider",
+		"version": "1.0.0",
+		"author": "Test Author",
+		"description": "A test extension"
+	}`
+
+	_, err := ParseManifest([]byte(invalidManifest))
+	if err == nil {
+		t.Fatal("Expected error for missing type")
+	}
+}
+
+func TestIsDomainAllowed(t *testing.T) {
+	manifest := &ExtensionManifest{
+		Permissions: ExtensionPermissions{
+			Network: []string{"api.test.com", "*.example.com"},
+		},
+	}
+
+	tests := []struct {
+		domain   string
+		expected bool
+	}{
+		{"api.test.com", true},
+		{"api.example.com", true},
+		{"sub.example.com", true},
+		{"notallowed.com", false},
+		{"test.com", false},
+	}
+
+	for _, tt := range tests {
+		result := manifest.IsDomainAllowed(tt.domain)
+		if result != tt.expected {
+			t.Errorf("IsDomainAllowed(%s) = %v, expected %v", tt.domain, result, tt.expected)
+		}
+	}
+}
+
+func TestExtensionRuntime_NetworkSandbox(t *testing.T) {
+	// Create a mock extension with limited network permissions
+	ext := &LoadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+			Permissions: ExtensionPermissions{
+				Network: []string{"api.allowed.com", "*.wildcard.com"},
+			},
+		},
+		DataDir: t.TempDir(),
+	}
+
+	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)
+	}
+
+	if err := runtime.validateDomain("https://sub.wildcard.com/path"); err != nil {
+		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")
+	}
+
+	if err := runtime.validateDomain("https://notallowed.com/path"); err == nil {
+		t.Error("Expected notallowed.com to be denied")
+	}
+}
+
+func TestExtensionRuntime_FileSandbox(t *testing.T) {
+	tempDir := t.TempDir()
+
+	ext := &LoadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+			Permissions: ExtensionPermissions{
+				File: true, // Enable file permission for test
+			},
+		},
+		DataDir: tempDir,
+	}
+
+	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)
+	}
+	if validPath == "" {
+		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)
+	}
+	if nestedPath == "" {
+		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
+	} else {
+		absPath = "/etc/passwd" // Unix
+	}
+	_, 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
+			},
+		},
+		DataDir: tempDir,
+	}
+	runtimeNoFile := NewExtensionRuntime(extNoFile)
+	_, err = runtimeNoFile.validatePath("test.txt")
+	if err == nil {
+		t.Error("Expected file access to be denied without file permission")
+	}
+}
+
+func TestExtensionRuntime_UtilityFunctions(t *testing.T) {
+	ext := &LoadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+		},
+		DataDir: t.TempDir(),
+	}
+
+	runtime := NewExtensionRuntime(ext)
+	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)
+	}
+	if result.String() != "aGVsbG8=" {
+		t.Errorf("Expected 'aGVsbG8=', got '%s'", result.String())
+	}
+
+	result, err = vm.RunString(`utils.base64Decode("aGVsbG8=")`)
+	if err != nil {
+		t.Fatalf("base64Decode failed: %v", err)
+	}
+	if result.String() != "hello" {
+		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)
+	}
+	if result.String() != "5d41402abc4b2a76b9719d911017c592" {
+		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)
+	}
+	// JSON output may vary in order, just check it's valid
+	if result.String() == "" {
+		t.Error("Expected non-empty JSON string")
+	}
+}
+
+func TestExtensionRuntime_SSRFProtection(t *testing.T) {
+	// Create extension with limited network permissions
+	ext := &LoadedExtension{
+		ID: "test-ext",
+		Manifest: &ExtensionManifest{
+			Name: "test-ext",
+			Permissions: ExtensionPermissions{
+				Network: []string{"api.example.com"},
+			},
+		},
+		DataDir: t.TempDir(),
+	}
+
+	runtime := NewExtensionRuntime(ext)
+
+	// Test that private IPs are blocked (SSRF protection)
+	privateIPs := []string{
+		"http://localhost/admin",
+		"http://127.0.0.1/admin",
+		"http://192.168.1.1/admin",
+		"http://10.0.0.1/admin",
+		"http://172.16.0.1/admin",
+		"http://169.254.169.254/latest/meta-data/", // AWS metadata
+		"http://router.local/admin",
+	}
+
+	for _, url := range privateIPs {
+		err := runtime.validateDomain(url)
+		if err == nil {
+			t.Errorf("Expected private IP/host '%s' to be blocked", url)
+		}
+	}
+
+	// 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)
+	}
+}
+
+func TestIsPrivateIP(t *testing.T) {
+	tests := []struct {
+		host     string
+		expected bool
+	}{
+		// Private IPs should be blocked
+		{"localhost", true},
+		{"127.0.0.1", true},
+		{"127.0.0.2", true},
+		{"10.0.0.1", true},
+		{"10.255.255.255", true},
+		{"172.16.0.1", true},
+		{"172.31.255.255", true},
+		{"192.168.0.1", true},
+		{"192.168.255.255", true},
+		{"169.254.169.254", true}, // AWS metadata
+		{"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
+	}
+
+	for _, tt := range tests {
+		result := isPrivateIP(tt.host)
+		if result != tt.expected {
+			t.Errorf("isPrivateIP(%s) = %v, expected %v", tt.host, result, tt.expected)
+		}
+	}
+}

go_backend/extension_timeout.go

@@ -0,0 +1,118 @@
+// Package gobackend provides timeout execution for extension JS code
+package gobackend
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	"github.com/dop251/goja"
+)
+
+// JSExecutionError represents an error during JS execution
+type JSExecutionError struct {
+	Message   string
+	IsTimeout bool
+}
+
+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
+	}
+
+	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()
+
+				if wasInterrupted {
+					resultCh <- result{nil, &JSExecutionError{
+						Message:   "execution timeout exceeded",
+						IsTimeout: true,
+					}}
+				} else {
+					resultCh <- result{nil, fmt.Errorf("panic during execution: %v", r)}
+				}
+			}
+		}()
+
+		val, err := vm.RunString(script)
+		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
+			}
+			return nil, &JSExecutionError{
+				Message:   "execution timeout exceeded",
+				IsTimeout: true,
+			}
+		case <-time.After(1 * time.Second):
+			// Force return timeout error
+			return nil, &JSExecutionError{
+				Message:   "execution timeout exceeded (force)",
+				IsTimeout: true,
+			}
+		}
+	}
+}
+
+// RunWithTimeoutAndRecover runs JS with timeout and clears interrupt state after
+// This should be used when you want to continue using the VM after a timeout
+func RunWithTimeoutAndRecover(vm *goja.Runtime, script string, timeout time.Duration) (goja.Value, error) {
+	result, err := RunWithTimeout(vm, script, timeout)
+
+	// Clear any interrupt state so VM can be reused
+	vm.ClearInterrupt()
+
+	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
+	}
+	return false
+}

go_backend/go.mod

@@ -5,14 +5,19 @@ go 1.24.0
 toolchain go1.24.5
 
 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
 )
 
 require (
+	github.com/dlclark/regexp2 v1.11.4 // indirect
+	github.com/go-sourcemap/sourcemap v2.1.3+incompatible // indirect
+	github.com/google/pprof v0.0.0-20230207041349-798e818bf904 // indirect
 	golang.org/x/mobile v0.0.0-20251209145715-2553ed8ce294 // indirect
 	golang.org/x/mod v0.31.0 // indirect
 	golang.org/x/sync v0.19.0 // indirect
+	golang.org/x/text v0.3.8 // indirect
 	golang.org/x/tools v0.40.0 // indirect
 )

go_backend/go.sum

@@ -1,14 +1,28 @@
+github.com/Masterminds/semver/v3 v3.2.1 h1:RN9w6+7QoMeJVGyfmbcgs28Br8cvmnucEXnY0rYXWg0=
+github.com/Masterminds/semver/v3 v3.2.1/go.mod h1:qvl/7zhW3nngYb5+80sSMF+FG2BjYrf8m9wsX0PNOMQ=
+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-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/pprof v0.0.0-20230207041349-798e818bf904 h1:4/hN5RUoecvl+RmJRE2YxKWtnnQls6rQjjW5oV7qg2U=
+github.com/google/pprof v0.0.0-20230207041349-798e818bf904/go.mod h1:uglQLonpP8qtYCYyzA+8c/9qtqgA3qsXGYqCPKARAFg=
 golang.org/x/mobile v0.0.0-20251209145715-2553ed8ce294 h1:Cr6kbEvA6nqvdHynE4CtVKlqpZB9dS1Jva/6IsHA19g=
 golang.org/x/mobile v0.0.0-20251209145715-2553ed8ce294/go.mod h1:RdZ+3sb4CVgpCFnzv+I4haEpwqFfsfzlLHs3L7ok+e0=
 golang.org/x/mod v0.31.0 h1:HaW9xtz0+kOcWKwli0ZXy79Ix+UW/vOfmWI5QVd2tgI=
 golang.org/x/mod v0.31.0/go.mod h1:43JraMp9cGx1Rx3AqioxrbrhNsLl2l/iNAvuBkrezpg=
 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/text v0.3.8 h1:nAL+RVCQ9uMn3vJZbV+MRnydTJFPf8qqY42YiA6MrqY=
+golang.org/x/text v0.3.8/go.mod h1:E6s5w1FMmriuDzIBO73fBruAKo1PCIq6d2Q6DHfQ8WQ=
 golang.org/x/tools v0.40.0 h1:yLkxfA+Qnul4cs9QA3KnlFu0lVmd8JJfoq+E41uSutA=
 golang.org/x/tools v0.40.0/go.mod h1:Ik/tzLRlbscWpqqMRjyWYDisX8bG13FrdXp3o4Sr9lc=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=

go_backend/httputil.go

@@ -22,11 +22,11 @@ import (
 func getRandomUserAgent() string {
 	// Windows 10/11 Chrome format - same as PC version for maximum compatibility
 	// Some APIs may block mobile User-Agents, so we use desktop format
-	winMajor := rand.Intn(2) + 10  // Windows 10 or 11
+	winMajor := rand.Intn(2) + 10 // Windows 10 or 11
 
-	chromeVersion := rand.Intn(25) + 100 // Chrome 100-124
+	chromeVersion := rand.Intn(25) + 100  // Chrome 100-124
 	chromeBuild := rand.Intn(1500) + 3000 // Build 3000-4500
-	chromePatch := rand.Intn(65) + 60 // Patch 60-125
+	chromePatch := rand.Intn(65) + 60     // Patch 60-125
 
 	return fmt.Sprintf(
 		"Mozilla/5.0 (Windows NT %d.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/%d.0.%d.%d Safari/537.36",
@@ -39,46 +39,48 @@ func getRandomUserAgent() string {
 
 // getRandomMacUserAgent generates a random Mac Chrome User-Agent string
 // Alternative format matching referensi/backend/spotify_metadata.go exactly
-func getRandomMacUserAgent() string {
+// Kept for potential future use
-	macMajor := rand.Intn(4) + 11  // macOS 11-14
+// func getRandomMacUserAgent() string {
-	macMinor := rand.Intn(5) + 4   // Minor 4-8
+// 	macMajor := rand.Intn(4) + 11 // macOS 11-14
-	webkitMajor := rand.Intn(7) + 530
+// 	macMinor := rand.Intn(5) + 4  // Minor 4-8
-	webkitMinor := rand.Intn(7) + 30
+// 	webkitMajor := rand.Intn(7) + 530
-	chromeMajor := rand.Intn(25) + 80
+// 	webkitMinor := rand.Intn(7) + 30
-	chromeBuild := rand.Intn(1500) + 3000
+// 	chromeMajor := rand.Intn(25) + 80
-	chromePatch := rand.Intn(65) + 60
+// 	chromeBuild := rand.Intn(1500) + 3000
-	safariMajor := rand.Intn(7) + 530
+// 	chromePatch := rand.Intn(65) + 60
-	safariMinor := rand.Intn(6) + 30
+// 	safariMajor := rand.Intn(7) + 530
-
+// 	safariMinor := rand.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",
+// 	return fmt.Sprintf(
-		macMajor,
+// 		"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",
-		macMinor,
+// 		macMajor,
-		webkitMajor,
+// 		macMinor,
-		webkitMinor,
+// 		webkitMajor,
-		chromeMajor,
+// 		webkitMinor,
-		chromeBuild,
+// 		chromeMajor,
-		chromePatch,
+// 		chromeBuild,
-		safariMajor,
+// 		chromePatch,
-		safariMinor,
+// 		safariMajor,
-	)
+// 		safariMinor,
-}
+// 	)
+// }
 
 // getRandomDesktopUserAgent randomly picks between Windows and Mac User-Agent
-func getRandomDesktopUserAgent() string {
+// Kept for potential future use
-	if rand.Intn(2) == 0 {
+// func getRandomDesktopUserAgent() string {
-		return getRandomUserAgent() // Windows
+// 	if rand.Intn(2) == 0 {
-	}
+// 		return getRandomUserAgent() // Windows
-	return getRandomMacUserAgent() // Mac
+// 	}
-}
+// 	return getRandomMacUserAgent() // Mac
+// }
 
 // Default timeout values
 const (
-	DefaultTimeout     = 60 * time.Second  // Default HTTP timeout
+	DefaultTimeout    = 60 * time.Second  // Default HTTP timeout
-	DownloadTimeout    = 120 * time.Second // Timeout for file downloads
+	DownloadTimeout   = 120 * time.Second // Timeout for file downloads
-	SongLinkTimeout    = 30 * time.Second  // Timeout for SongLink API
+	SongLinkTimeout   = 30 * time.Second  // Timeout for SongLink API
-	DefaultMaxRetries  = 3                 // Default retry count
+	DefaultMaxRetries = 3                 // Default retry count
-	DefaultRetryDelay  = 1 * time.Second   // Initial retry delay
+	DefaultRetryDelay = 1 * time.Second   // Initial retry delay
 )
 
 // Shared transport with connection pooling to prevent TCP exhaustion
@@ -96,9 +98,9 @@ var sharedTransport = &http.Transport{
 	ExpectContinueTimeout: 1 * time.Second,
 	DisableKeepAlives:     false, // Enable keep-alives for connection reuse
 	ForceAttemptHTTP2:     true,
-	WriteBufferSize:       64 * 1024,  // 64KB write buffer
+	WriteBufferSize:       64 * 1024, // 64KB write buffer
-	ReadBufferSize:        64 * 1024,  // 64KB read buffer
+	ReadBufferSize:        64 * 1024, // 64KB read buffer
-	DisableCompression:    true,       // FLAC is already compressed
+	DisableCompression:    true,      // FLAC is already compressed
 }
 
 // Shared HTTP client for general requests (reuses connections)
@@ -267,10 +269,7 @@ func DoRequestWithRetry(client *http.Client, req *http.Request, config RetryConf
 // calculateNextDelay calculates the next delay with exponential backoff
 func calculateNextDelay(currentDelay time.Duration, config RetryConfig) time.Duration {
 	nextDelay := time.Duration(float64(currentDelay) * config.BackoffFactor)
-	if nextDelay > config.MaxDelay {
+	return min(nextDelay, config.MaxDelay)
-		nextDelay = config.MaxDelay
-	}
-	return nextDelay
 }
 
 // getRetryAfterDuration parses Retry-After header and returns duration

go_backend/logbuffer.go

@@ -33,9 +33,9 @@ var (
 func GetLogBuffer() *LogBuffer {
 	logBufferOnce.Do(func() {
 		globalLogBuffer = &LogBuffer{
-			entries:        make([]LogEntry, 0, 500),
+			entries:        make([]LogEntry, 0, 1000),
-			maxSize:        500,
+			maxSize:        1000,
-			loggingEnabled: false, // Default: disabled for performance
+			loggingEnabled: false, // Default: disabled for performance (user can enable in settings)
 		}
 	})
 	return globalLogBuffer

go_backend/lyrics.go

@@ -250,29 +250,30 @@ func msToLRCTimestamp(ms int64) string {
 
 // convertToLRC converts lyrics to LRC format string (without metadata headers)
 // Use convertToLRCWithMetadata for full LRC with headers
-func convertToLRC(lyrics *LyricsResponse) string {
+// Kept for potential future use
-	if lyrics == nil || len(lyrics.Lines) == 0 {
+// func convertToLRC(lyrics *LyricsResponse) string {
-		return ""
+// 	if lyrics == nil || len(lyrics.Lines) == 0 {
-	}
+// 		return ""
-
+// 	}
-	var builder strings.Builder
+//
-
+// 	var builder strings.Builder
-	if lyrics.SyncType == "LINE_SYNCED" {
+//
-		for _, line := range lyrics.Lines {
+// 	if lyrics.SyncType == "LINE_SYNCED" {
-			timestamp := msToLRCTimestamp(line.StartTimeMs)
+// 		for _, line := range lyrics.Lines {
-			builder.WriteString(timestamp)
+// 			timestamp := msToLRCTimestamp(line.StartTimeMs)
-			builder.WriteString(line.Words)
+// 			builder.WriteString(timestamp)
-			builder.WriteString("\n")
+// 			builder.WriteString(line.Words)
-		}
+// 			builder.WriteString("\n")
-	} else {
+// 		}
-		for _, line := range lyrics.Lines {
+// 	} else {
-			builder.WriteString(line.Words)
+// 		for _, line := range lyrics.Lines {
-			builder.WriteString("\n")
+// 			builder.WriteString(line.Words)
-		}
+// 			builder.WriteString("\n")
-	}
+// 		}
-
+// 	}
-	return builder.String()
+//
-}
+// 	return builder.String()
+// }
 
 // convertToLRCWithMetadata converts lyrics to LRC format with metadata headers
 // Includes [ti:], [ar:], [by:] headers

go_backend/metadata.go

@@ -400,8 +400,9 @@ func ExtractLyrics(filePath string) (string, error) {
 
 // AudioQuality represents audio quality info from a FLAC file
 type AudioQuality struct {
-	BitDepth   int `json:"bit_depth"`
+	BitDepth     int   `json:"bit_depth"`
-	SampleRate int `json:"sample_rate"`
+	SampleRate   int   `json:"sample_rate"`
+	TotalSamples int64 `json:"total_samples"`
 }
 
 // GetAudioQuality reads bit depth and sample rate from a FLAC file's StreamInfo block
@@ -446,9 +447,17 @@ func GetAudioQuality(filePath string) (AudioQuality, error) {
 		// Parse bits per sample (5 bits)
 		bitsPerSample := ((int(streamInfo[12]) & 0x01) << 4) | (int(streamInfo[13]) >> 4) + 1
 
+		// Parse total samples (36 bits: 4 bits from byte 13, all of bytes 14-17)
+		totalSamples := int64(streamInfo[13]&0x0F)<<32 |
+			int64(streamInfo[14])<<24 |
+			int64(streamInfo[15])<<16 |
+			int64(streamInfo[16])<<8 |
+			int64(streamInfo[17])
+
 		return AudioQuality{
-			BitDepth:   bitsPerSample,
+			BitDepth:     bitsPerSample,
-			SampleRate: sampleRate,
+			SampleRate:   sampleRate,
+			TotalSamples: totalSamples,
 		}, nil
 	}
 
@@ -469,7 +478,6 @@ func GetAudioQuality(filePath string) (AudioQuality, error) {
 	return AudioQuality{}, fmt.Errorf("unsupported file format (not FLAC or M4A)")
 }
 
-
 // ========================================
 // M4A (MP4/AAC) Metadata Embedding
 // ========================================
@@ -490,7 +498,7 @@ func EmbedM4AMetadata(filePath string, metadata Metadata, coverData []byte) erro
 	}
 
 	// Find udta atom inside moov, or create one
-	moovSize := int(data[moovPos]<<24 | data[moovPos+1]<<16 | data[moovPos+2]<<8 | data[moovPos+3])
+	moovSize := int(uint32(data[moovPos])<<24 | uint32(data[moovPos+1])<<16 | uint32(data[moovPos+2])<<8 | uint32(data[moovPos+3]))
 	udtaPos := findAtom(data, "udta", moovPos+8)
 
 	// Build new metadata atoms
@@ -499,12 +507,12 @@ func EmbedM4AMetadata(filePath string, metadata Metadata, coverData []byte) erro
 	var newData []byte
 	if udtaPos >= 0 && udtaPos < moovPos+moovSize {
 		// udta exists, find meta inside it or replace
-		udtaSize := int(data[udtaPos]<<24 | data[udtaPos+1]<<16 | data[udtaPos+2]<<8 | data[udtaPos+3])
+		udtaSize := int(uint32(data[udtaPos])<<24 | uint32(data[udtaPos+1])<<16 | uint32(data[udtaPos+2])<<8 | uint32(data[udtaPos+3]))
 		metaPos := findAtom(data, "meta", udtaPos+8)
 
 		if metaPos >= 0 && metaPos < udtaPos+udtaSize {
 			// Replace existing meta atom
-			metaSize := int(data[metaPos]<<24 | data[metaPos+1]<<16 | data[metaPos+2]<<8 | data[metaPos+3])
+			metaSize := int(uint32(data[metaPos])<<24 | uint32(data[metaPos+1])<<16 | uint32(data[metaPos+2])<<8 | uint32(data[metaPos+3]))
 			newData = append(newData, data[:metaPos]...)
 			newData = append(newData, metaAtom...)
 			newData = append(newData, data[metaPos+metaSize:]...)
@@ -562,7 +570,7 @@ func EmbedM4AMetadata(filePath string, metadata Metadata, coverData []byte) erro
 // findAtom finds an atom by name starting from offset
 func findAtom(data []byte, name string, offset int) int {
 	for i := offset; i < len(data)-8; {
-		size := int(data[i]<<24 | data[i+1]<<16 | data[i+2]<<8 | data[i+3])
+		size := int(uint32(data[i])<<24 | uint32(data[i+1])<<16 | uint32(data[i+2])<<8 | uint32(data[i+3]))
 		if size < 8 {
 			break
 		}

go_backend/parallel.go

@@ -233,7 +233,7 @@ func PreWarmTrackCache(requests []PreWarmCacheRequest) {
 	fmt.Printf("[Cache] Pre-warm complete. Cache size: %d\n", cache.Size())
 }
 
-func preWarmTidalCache(isrc, trackName, artistName string) {
+func preWarmTidalCache(isrc, _, _ string) {
 	downloader := NewTidalDownloader()
 	track, err := downloader.SearchTrackByISRC(isrc)
 	if err == nil && track != nil {

go_backend/progress.go

@@ -23,7 +23,7 @@ type ItemProgress struct {
 	ItemID        string  `json:"item_id"`
 	BytesTotal    int64   `json:"bytes_total"`
 	BytesReceived int64   `json:"bytes_received"`
-	Progress      float64 `json:"progress"` // 0.0 to 1.0
+	Progress      float64 `json:"progress"`   // 0.0 to 1.0
 	SpeedMBps     float64 `json:"speed_mbps"` // Download speed in MB/s
 	IsDownloading bool    `json:"is_downloading"`
 	Status        string  `json:"status"` // "downloading", "finalizing", "completed"
@@ -204,11 +204,12 @@ func setDownloadDir(path string) error {
 }
 
 // getDownloadDir returns the default download directory
-func getDownloadDir() string {
+// Kept for potential future use
-	downloadDirMu.RLock()
+// func getDownloadDir() string {
-	defer downloadDirMu.RUnlock()
+// 	downloadDirMu.RLock()
-	return downloadDir
+// 	defer downloadDirMu.RUnlock()
-}
+// 	return downloadDir
+// }
 
 // ItemProgressWriter wraps io.Writer to track download progress for a specific item
 type ItemProgressWriter struct {
@@ -239,6 +240,9 @@ 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
+	}
 	n, err := pw.writer.Write(p)
 	if err != nil {
 		return n, err

go_backend/qobuz.go

@@ -1,9 +1,11 @@
 package gobackend
 
 import (
+	"context"
 	"bufio"
 	"encoding/base64"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -12,6 +14,7 @@ import (
 	"path/filepath"
 	"strings"
 	"sync"
+	"time"
 )
 
 // QobuzDownloader handles Qobuz downloads
@@ -63,24 +66,27 @@ func qobuzArtistsMatch(expectedArtist, foundArtist string) bool {
 		return true
 	}
 
-	// Check first artist (before comma or feat)
+	// Split expected artists by common separators (comma, feat, ft., &, and)
-	expectedFirst := strings.Split(normExpected, ",")[0]
+	// e.g., "RADWIMPS, Toko Miura" or "RADWIMPS feat. Toko Miura"
-	expectedFirst = strings.Split(expectedFirst, " feat")[0]
+	expectedArtists := qobuzSplitArtists(normExpected)
-	expectedFirst = strings.Split(expectedFirst, " ft.")[0]
+	foundArtists := qobuzSplitArtists(normFound)
-	expectedFirst = strings.TrimSpace(expectedFirst)
 
-	foundFirst := strings.Split(normFound, ",")[0]
+	// Check if ANY expected artist matches ANY found artist
-	foundFirst = strings.Split(foundFirst, " feat")[0]
+	for _, exp := range expectedArtists {
-	foundFirst = strings.Split(foundFirst, " ft.")[0]
+		for _, fnd := range foundArtists {
-	foundFirst = strings.TrimSpace(foundFirst)
+			if exp == fnd {
-
+				return true
-	if expectedFirst == foundFirst {
+			}
-		return true
+			// Also check contains for partial matches
-	}
+			if strings.Contains(exp, fnd) || strings.Contains(fnd, exp) {
-
+				return true
-	// Check if first artist is contained in the other
+			}
-	if strings.Contains(expectedFirst, foundFirst) || strings.Contains(foundFirst, expectedFirst) {
+			// Check same words different order
-		return true
+			if qobuzSameWordsUnordered(exp, fnd) {
+				GoLog("[Qobuz] Artist names have same words in different order: '%s' vs '%s'\n", exp, fnd)
+				return true
+			}
+		}
 	}
 
 	// If scripts are TRULY different (Latin vs CJK/Arabic/Cyrillic), assume match (transliteration)
@@ -95,6 +101,67 @@ func qobuzArtistsMatch(expectedArtist, foundArtist string) bool {
 	return false
 }
 
+// qobuzSplitArtists splits artist string by common separators
+func qobuzSplitArtists(artists string) []string {
+	// Replace common separators with a standard one
+	normalized := artists
+	normalized = strings.ReplaceAll(normalized, " feat. ", "|")
+	normalized = strings.ReplaceAll(normalized, " feat ", "|")
+	normalized = strings.ReplaceAll(normalized, " ft. ", "|")
+	normalized = strings.ReplaceAll(normalized, " ft ", "|")
+	normalized = strings.ReplaceAll(normalized, " & ", "|")
+	normalized = strings.ReplaceAll(normalized, " and ", "|")
+	normalized = strings.ReplaceAll(normalized, ", ", "|")
+	normalized = strings.ReplaceAll(normalized, " x ", "|")
+
+	parts := strings.Split(normalized, "|")
+	result := make([]string, 0, len(parts))
+	for _, p := range parts {
+		trimmed := strings.TrimSpace(p)
+		if trimmed != "" {
+			result = append(result, trimmed)
+		}
+	}
+	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] {
+				sortedA[i], sortedA[j] = sortedA[j], sortedA[i]
+			}
+			if sortedB[i] > sortedB[j] {
+				sortedB[i], sortedB[j] = sortedB[j], sortedB[i]
+			}
+		}
+	}
+
+	for i := range sortedA {
+		if sortedA[i] != sortedB[i] {
+			return false
+		}
+	}
+	return true
+}
+
 // qobuzTitlesMatch checks if track titles are similar enough
 func qobuzTitlesMatch(expectedTitle, foundTitle string) bool {
 	normExpected := strings.ToLower(strings.TrimSpace(expectedTitle))
@@ -271,14 +338,15 @@ func qobuzIsLatinScript(s string) bool {
 }
 
 // qobuzIsASCIIString checks if a string contains only ASCII characters
-func qobuzIsASCIIString(s string) bool {
+// Kept for potential future use
-	for _, r := range s {
+// func qobuzIsASCIIString(s string) bool {
-		if r > 127 {
+// 	for _, r := range s {
-			return false
+// 		if r > 127 {
-		}
+// 			return false
-	}
+// 		}
-	return true
+// 	}
-}
+// 	return true
+// }
 
 // containsQueryQobuz checks if a query already exists in the list
 func containsQueryQobuz(queries []string, query string) bool {
@@ -301,6 +369,35 @@ func NewQobuzDownloader() *QobuzDownloader {
 	return globalQobuzDownloader
 }
 
+// GetTrackByID fetches track info directly by Qobuz track ID
+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)
+
+	req, err := http.NewRequest("GET", trackURL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := DoRequestWithUserAgent(q.client, req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("get track failed: HTTP %d", resp.StatusCode)
+	}
+
+	var track QobuzTrack
+	if err := json.NewDecoder(resp.Body).Decode(&track); err != nil {
+		return nil, err
+	}
+
+	return &track, nil
+}
+
 // GetAvailableAPIs returns list of available Qobuz APIs
 // Uses same APIs as PC version for compatibility
 func (q *QobuzDownloader) GetAvailableAPIs() []string {
@@ -634,85 +731,132 @@ func (q *QobuzDownloader) SearchTrackByMetadataWithDuration(trackName, artistNam
 	return nil, fmt.Errorf("no matching track found for: %s - %s", artistName, trackName)
 }
 
-// getQobuzDownloadURLSequential requests download URL from APIs sequentially
+// qobuzAPIResult holds the result from a parallel API request
-// Uses same URL format as PC version: /api/stream?trackId={id}&quality={quality}
+type qobuzAPIResult struct {
-func getQobuzDownloadURLSequential(apis []string, trackID int64, quality string) (string, string, error) {
+	apiURL      string
+	downloadURL string
+	err         error
+	duration    time.Duration
+}
+
+// getQobuzDownloadURLParallel requests download URL from all APIs in parallel
+// "Siapa cepat dia dapat" - first successful response wins
+func getQobuzDownloadURLParallel(apis []string, trackID int64, quality string) (string, string, error) {
 	if len(apis) == 0 {
 		return "", "", fmt.Errorf("no APIs available")
 	}
 
-	client := NewHTTPClientWithTimeout(DefaultTimeout)
+	GoLog("[Qobuz] Requesting download URL from %d APIs in parallel...\n", len(apis))
-	retryConfig := DefaultRetryConfig()
-	var errors []string
 
+	resultChan := make(chan qobuzAPIResult, len(apis))
+	startTime := time.Now()
+
+	// Start all requests in parallel
 	for _, apiURL := range apis {
-		// All APIs now use same format: https://domain/api/stream?trackId={id}&quality={quality}
+		go func(api string) {
-		// The apiURL already includes the path, just append trackID and quality
+			reqStart := time.Now()
-		reqURL := fmt.Sprintf("%s%d&quality=%s", apiURL, trackID, quality)
 
-		GoLog("[Qobuz] Trying: %s\n", reqURL)
+			client := &http.Client{
+				Timeout: 15 * time.Second,
+			}
 
-		req, err := http.NewRequest("GET", reqURL, nil)
+			reqURL := fmt.Sprintf("%s%d&quality=%s", api, trackID, quality)
-		if err != nil {
-			errors = append(errors, BuildErrorMessage(apiURL, 0, err.Error()))
-			continue
-		}
 
-		resp, err := DoRequestWithRetry(client, req, retryConfig)
+			req, err := http.NewRequest("GET", reqURL, nil)
-		if err != nil {
+			if err != nil {
-			errors = append(errors, BuildErrorMessage(apiURL, 0, err.Error()))
+				resultChan <- qobuzAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-			continue
+				return
-		}
+			}
 
-		body, err := ReadResponseBody(resp)
+			resp, err := client.Do(req)
-		resp.Body.Close()
+			if err != nil {
-		if err != nil {
+				resultChan <- qobuzAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-			errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, err.Error()))
+				return
-			continue
+			}
-		}
+			defer resp.Body.Close()
 
-		// Check if response is HTML (error page)
+			if resp.StatusCode != 200 {
-		if len(body) > 0 && body[0] == '<' {
+				resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("HTTP %d", resp.StatusCode), duration: time.Since(reqStart)}
-			errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, "received HTML instead of JSON"))
+				return
-			continue
+			}
-		}
 
-		// Check for error in JSON response
+			body, err := io.ReadAll(resp.Body)
-		var errorResp struct {
+			if err != nil {
-			Error string `json:"error"`
+				resultChan <- qobuzAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-		}
+				return
-		if json.Unmarshal(body, &errorResp) == nil && errorResp.Error != "" {
+			}
-			errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, errorResp.Error))
-			continue
-		}
 
-		var result struct {
+			// Check if response is HTML (error page)
-			URL string `json:"url"`
+			if len(body) > 0 && body[0] == '<' {
-		}
+				resultChan <- qobuzAPIResult{apiURL: api, err: fmt.Errorf("received HTML instead of JSON"), duration: time.Since(reqStart)}
-		if err := json.Unmarshal(body, &result); err != nil {
+				return
-			errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, "invalid JSON: "+err.Error()))
+			}
-			continue
-		}
 
-		if result.URL != "" {
+			// Check for error in JSON response
-			GoLog("[Qobuz] Got download URL from: %s\n", apiURL)
+			var errorResp struct {
-			return apiURL, result.URL, nil
+				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
+			}
 
-		errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, "no download URL in response"))
+			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++ {
+		result := <-resultChan
+		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
+				}
+			}(len(apis) - i - 1)
+
+			GoLog("[Qobuz] [Parallel] Total time: %v (first success)\n", time.Since(startTime))
+			return result.apiURL, result.downloadURL, nil
+		}
+		errMsg := result.err.Error()
+		if len(errMsg) > 50 {
+			errMsg = errMsg[:50] + "..."
+		}
+		errors = append(errors, fmt.Sprintf("%s: %s", result.apiURL, errMsg))
+	}
+
+	GoLog("[Qobuz] [Parallel] All %d APIs failed in %v\n", len(apis), time.Since(startTime))
 	return "", "", fmt.Errorf("all %d Qobuz APIs failed. Errors: %v", len(apis), errors)
 }
 
-// GetDownloadURL gets download URL for a track - tries APIs sequentially
+// GetDownloadURL gets download URL for a track - tries ALL APIs in parallel
+// "Siapa cepat dia dapat" - first successful response wins
 func (q *QobuzDownloader) GetDownloadURL(trackID int64, quality string) (string, error) {
 	apis := q.GetAvailableAPIs()
 	if len(apis) == 0 {
 		return "", fmt.Errorf("no Qobuz API available")
 	}
 
-	_, downloadURL, err := getQobuzDownloadURLSequential(apis, trackID, quality)
+	// Use parallel approach - request from all APIs simultaneously
+	_, downloadURL, err := getQobuzDownloadURLParallel(apis, trackID, quality)
 	if err != nil {
 		return "", err
 	}
@@ -722,19 +866,30 @@ func (q *QobuzDownloader) GetDownloadURL(trackID int64, quality string) (string,
 
 // DownloadFile downloads a file from URL with User-Agent and progress tracking
 func (q *QobuzDownloader) DownloadFile(downloadURL, outputPath, itemID string) error {
+	ctx := context.Background()
+
 	// Initialize item progress (required for all downloads)
 	if itemID != "" {
 		StartItemProgress(itemID)
 		defer CompleteItemProgress(itemID)
+		ctx = initDownloadCancel(itemID)
+		defer clearDownloadCancel(itemID)
 	}
 
-	req, err := http.NewRequest("GET", downloadURL, nil)
+	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(q.client, req)
 	if err != nil {
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		return err
 	}
 	defer resp.Body.Close()
@@ -774,6 +929,9 @@ func (q *QobuzDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 	// Check for any errors
 	if err != nil {
 		os.Remove(outputPath)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		return fmt.Errorf("download interrupted: %w", err)
 	}
 	if flushErr != nil {
@@ -823,8 +981,23 @@ func downloadFromQobuz(req DownloadRequest) (QobuzDownloadResult, error) {
 	var track *QobuzTrack
 	var err error
 
+	// STRATEGY 0: Use pre-fetched Qobuz ID from Odesli enrichment (highest priority)
+	if req.QobuzID != "" {
+		GoLog("[Qobuz] Using Qobuz ID from Odesli enrichment: %s\n", req.QobuzID)
+		var trackID int64
+		if _, parseErr := fmt.Sscanf(req.QobuzID, "%d", &trackID); parseErr == nil && trackID > 0 {
+			track, err = downloader.GetTrackByID(trackID)
+			if err != nil {
+				GoLog("[Qobuz] Failed to get track by Odesli ID %d: %v\n", trackID, err)
+				track = nil
+			} else if track != nil {
+				GoLog("[Qobuz] Successfully found track via Odesli ID: '%s' by '%s'\n", track.Title, track.Performer.Name)
+			}
+		}
+	}
+
 	// OPTIMIZATION: Check cache first for track ID
-	if req.ISRC != "" {
+	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
@@ -938,6 +1111,9 @@ 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 errors.Is(err, ErrDownloadCancelled) {
+			return QobuzDownloadResult{}, ErrDownloadCancelled
+		}
 		return QobuzDownloadResult{}, fmt.Errorf("download failed: %w", err)
 	}
 

go_backend/spotify.go

@@ -2,7 +2,6 @@ package gobackend
 
 import (
 	"context"
-	"encoding/base64"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -17,13 +16,13 @@ import (
 )
 
 const (
-	spotifyTokenURL     = "https://accounts.spotify.com/api/token"
+	spotifyTokenURL = "https://accounts.spotify.com/api/token"
-	playlistBaseURL     = "https://api.spotify.com/v1/playlists/%s"
+	playlistBaseURL = "https://api.spotify.com/v1/playlists/%s"
-	albumBaseURL        = "https://api.spotify.com/v1/albums/%s"
+	albumBaseURL    = "https://api.spotify.com/v1/albums/%s"
-	trackBaseURL        = "https://api.spotify.com/v1/tracks/%s"
+	trackBaseURL    = "https://api.spotify.com/v1/tracks/%s"
-	artistBaseURL       = "https://api.spotify.com/v1/artists/%s"
+	artistBaseURL   = "https://api.spotify.com/v1/artists/%s"
-	artistAlbumsURL     = "https://api.spotify.com/v1/artists/%s/albums"
+	artistAlbumsURL = "https://api.spotify.com/v1/artists/%s/albums"
-	searchBaseURL       = "https://api.spotify.com/v1/search"
+	searchBaseURL   = "https://api.spotify.com/v1/search"
 
 	// Cache TTL settings
 	artistCacheTTL = 10 * time.Minute
@@ -69,8 +68,10 @@ 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
-// Pass empty strings to use default credentials
 func SetSpotifyCredentials(clientID, clientSecret string) {
 	credentialsMu.Lock()
 	defer credentialsMu.Unlock()
@@ -78,39 +79,56 @@ func SetSpotifyCredentials(clientID, clientSecret string) {
 	customClientSecret = clientSecret
 }
 
-// getCredentials returns the current credentials (custom or default)
+// HasSpotifyCredentials checks if Spotify credentials are configured
-func getCredentials() (string, string) {
+func HasSpotifyCredentials() bool {
 	credentialsMu.RLock()
 	defer credentialsMu.RUnlock()
 
+	// Check custom credentials first
 	if customClientID != "" && customClientSecret != "" {
-		return customClientID, customClientSecret
+		return true
 	}
 
-	// Fall back to default credentials
+	// Check environment variables
+	if os.Getenv("SPOTIFY_CLIENT_ID") != "" && os.Getenv("SPOTIFY_CLIENT_SECRET") != "" {
+		return true
+	}
+
+	return false
+}
+
+// getCredentials returns the current credentials or error if not configured
+func getCredentials() (string, string, error) {
+	credentialsMu.RLock()
+	defer credentialsMu.RUnlock()
+
+	// Check custom credentials first
+	if customClientID != "" && customClientSecret != "" {
+		return customClientID, customClientSecret, nil
+	}
+
+	// Check environment variables
 	clientID := os.Getenv("SPOTIFY_CLIENT_ID")
-	if clientID == "" {
-		if decoded, err := base64.StdEncoding.DecodeString("NWY1NzNjOTYyMDQ5NGJhZTg3ODkwYzBmMDhhNjAyOTM="); err == nil {
-			clientID = string(decoded)
-		}
-	}
-
 	clientSecret := os.Getenv("SPOTIFY_CLIENT_SECRET")
-	if clientSecret == "" {
+
-		if decoded, err := base64.StdEncoding.DecodeString("MjEyNDc2ZDliMGYzNDcyZWFhNzYyZDkwYjE5YjBiYTg="); err == nil {
+	if clientID != "" && clientSecret != "" {
-			clientSecret = string(decoded)
+		return clientID, clientSecret, nil
-		}
 	}
 
-	return clientID, clientSecret
+	// No credentials available
+	return "", "", ErrNoSpotifyCredentials
 }
 
 // NewSpotifyMetadataClient creates a new Spotify client
-func NewSpotifyMetadataClient() *SpotifyMetadataClient {
+// Returns error if credentials are not configured
-	src := rand.NewSource(time.Now().UnixNano())
+func NewSpotifyMetadataClient() (*SpotifyMetadataClient, error) {
+	// Get credentials - will error if not configured
+	clientID, clientSecret, err := getCredentials()
+	if err != nil {
+		return nil, err
+	}
 
-	// Get credentials (custom or default)
+	src := rand.NewSource(time.Now().UnixNano())
-	clientID, clientSecret := getCredentials()
 
 	c := &SpotifyMetadataClient{
 		httpClient:   NewHTTPClientWithTimeout(15 * time.Second), // Use shared transport for connection pooling
@@ -122,7 +140,7 @@ func NewSpotifyMetadataClient() *SpotifyMetadataClient {
 		albumCache:   make(map[string]*cacheEntry),
 	}
 	c.userAgent = c.randomUserAgent()
-	return c
+	return c, nil
 }
 
 // TrackMetadata represents track information
@@ -140,6 +158,7 @@ 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
 }
 
 // AlbumTrackMetadata holds per-track info for album/playlist
@@ -159,6 +178,7 @@ type AlbumTrackMetadata struct {
 	ISRC        string `json:"isrc"`
 	AlbumID     string `json:"album_id,omitempty"`
 	AlbumURL    string `json:"album_url,omitempty"`
+	AlbumType   string `json:"album_type,omitempty"` // album, single, ep, compilation
 }
 
 // AlbumInfoMetadata holds album information
@@ -283,6 +303,7 @@ type albumSimplified struct {
 	Images      []image     `json:"images"`
 	ExternalURL externalURL `json:"external_urls"`
 	Artists     []artist    `json:"artists"`
+	AlbumType   string      `json:"album_type"` // album, single, compilation
 }
 
 type trackFull struct {
@@ -363,6 +384,7 @@ func (c *SpotifyMetadataClient) SearchTracks(ctx context.Context, query string,
 			DiscNumber:  track.DiscNumber,
 			ExternalURL: track.ExternalURL.Spotify,
 			ISRC:        track.ExternalID.ISRC,
+			AlbumType:   track.Album.AlbumType,
 		})
 	}
 
@@ -395,10 +417,10 @@ func (c *SpotifyMetadataClient) SearchAll(ctx context.Context, query string, tra
 		} `json:"tracks"`
 		Artists struct {
 			Items []struct {
-				ID         string  `json:"id"`
+				ID        string  `json:"id"`
-				Name       string  `json:"name"`
+				Name      string  `json:"name"`
-				Images     []image `json:"images"`
+				Images    []image `json:"images"`
-				Followers  struct {
+				Followers struct {
 					Total int `json:"total"`
 				} `json:"followers"`
 				Popularity int `json:"popularity"`
@@ -430,6 +452,7 @@ func (c *SpotifyMetadataClient) SearchAll(ctx context.Context, query string, tra
 			DiscNumber:  track.DiscNumber,
 			ExternalURL: track.ExternalURL.Spotify,
 			ISRC:        track.ExternalID.ISRC,
+			AlbumType:   track.Album.AlbumType,
 		})
 	}
 
@@ -755,10 +778,10 @@ func (c *SpotifyMetadataClient) fetchArtist(ctx context.Context, artistID, token
 
 	// Fetch artist info
 	var artistData struct {
-		ID         string  `json:"id"`
+		ID        string  `json:"id"`
-		Name       string  `json:"name"`
+		Name      string  `json:"name"`
-		Images     []image `json:"images"`
+		Images    []image `json:"images"`
-		Followers  struct {
+		Followers struct {
 			Total int `json:"total"`
 		} `json:"followers"`
 		Popularity int `json:"popularity"`
@@ -941,15 +964,15 @@ func (c *SpotifyMetadataClient) randomUserAgent() string {
 	defer c.rngMu.Unlock()
 
 	// Use Mac User-Agent format (same as PC version)
-	macMajor := c.rng.Intn(4) + 11    // 11-14
+	macMajor := c.rng.Intn(4) + 11         // 11-14
-	macMinor := c.rng.Intn(5) + 4     // 4-8
+	macMinor := c.rng.Intn(5) + 4          // 4-8
-	webkitMajor := c.rng.Intn(7) + 530 // 530-536
+	webkitMajor := c.rng.Intn(7) + 530     // 530-536
-	webkitMinor := c.rng.Intn(7) + 30  // 30-36
+	webkitMinor := c.rng.Intn(7) + 30      // 30-36
-	chromeMajor := c.rng.Intn(25) + 80 // 80-104
+	chromeMajor := c.rng.Intn(25) + 80     // 80-104
 	chromeBuild := c.rng.Intn(1500) + 3000 // 3000-4499
-	chromePatch := c.rng.Intn(65) + 60 // 60-124
+	chromePatch := c.rng.Intn(65) + 60     // 60-124
-	safariMajor := c.rng.Intn(7) + 530 // 530-536
+	safariMajor := c.rng.Intn(7) + 530     // 530-536
-	safariMinor := c.rng.Intn(6) + 30  // 30-35
+	safariMinor := c.rng.Intn(6) + 30      // 30-35
 
 	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

@@ -1,10 +1,12 @@
 package gobackend
 
 import (
+	"context"
 	"bufio"
 	"encoding/base64"
 	"encoding/json"
 	"encoding/xml"
+	"errors"
 	"fmt"
 	"io"
 	"net/http"
@@ -345,27 +347,28 @@ func (t *TidalDownloader) SearchTrackByISRC(isrc string) (*TidalTrack, error) {
 	return nil, fmt.Errorf("no exact ISRC match found for: %s", isrc)
 }
 
-// normalizeTitle normalizes a track title for comparison (kept for potential future use)
+// normalizeTitle normalizes a track title for comparison
-func normalizeTitle(title string) string {
+// Kept for potential future use
-	normalized := strings.ToLower(strings.TrimSpace(title))
+// func normalizeTitle(title string) string {
-
+// 	normalized := strings.ToLower(strings.TrimSpace(title))
-	// Remove common suffixes in parentheses or brackets
+//
-	suffixPatterns := []string{
+// 	// Remove common suffixes in parentheses or brackets
-		" (remaster)", " (remastered)", " (deluxe)", " (deluxe edition)",
+// 	suffixPatterns := []string{
-		" (bonus track)", " (single)", " (album version)", " (radio edit)",
+// 		" (remaster)", " (remastered)", " (deluxe)", " (deluxe edition)",
-		" [remaster]", " [remastered]", " [deluxe]", " [bonus track]",
+// 		" (bonus track)", " (single)", " (album version)", " (radio edit)",
-	}
+// 		" [remaster]", " [remastered]", " [deluxe]", " [bonus track]",
-	for _, suffix := range suffixPatterns {
+// 	}
-		normalized = strings.TrimSuffix(normalized, suffix)
+// 	for _, suffix := range suffixPatterns {
-	}
+// 		normalized = strings.TrimSuffix(normalized, suffix)
-
+// 	}
-	// Remove multiple spaces
+//
-	for strings.Contains(normalized, "  ") {
+// 	// Remove multiple spaces
-		normalized = strings.ReplaceAll(normalized, "  ", " ")
+// 	for strings.Contains(normalized, "  ") {
-	}
+// 		normalized = strings.ReplaceAll(normalized, "  ", " ")
-
+// 	}
-	return normalized
+//
-}
+// 	return normalized
+// }
 
 // SearchTrackByMetadataWithISRC searches for a track with ISRC matching priority
 // Now includes romaji conversion for Japanese text (4 search strategies like PC)
@@ -638,103 +641,144 @@ type TidalDownloadInfo struct {
 	SampleRate int
 }
 
-// getDownloadURLSequential requests download URL from APIs sequentially
+// tidalAPIResult holds the result from a parallel API request
+type tidalAPIResult struct {
+	apiURL   string
+	info     TidalDownloadInfo
+	err      error
+	duration time.Duration
+}
+
+// getDownloadURLParallel requests download URL from all APIs in parallel
 // Returns the first successful result (supports both v1 and v2 API formats)
-func getDownloadURLSequential(apis []string, trackID int64, quality string) (string, TidalDownloadInfo, error) {
+// "Siapa cepat dia dapat" - first success wins
+func getDownloadURLParallel(apis []string, trackID int64, quality string) (string, TidalDownloadInfo, error) {
 	if len(apis) == 0 {
 		return "", TidalDownloadInfo{}, fmt.Errorf("no APIs available")
 	}
 
-	client := NewHTTPClientWithTimeout(DefaultTimeout)
+	GoLog("[Tidal] Requesting download URL from %d APIs in parallel...\n", len(apis))
-	retryConfig := DefaultRetryConfig()
-	var errors []string
 
+	resultChan := make(chan tidalAPIResult, len(apis))
+	startTime := time.Now()
+
+	// Start all requests in parallel
 	for _, apiURL := range apis {
-		reqURL := fmt.Sprintf("%s/track/?id=%d&quality=%s", apiURL, trackID, quality)
+		go func(api string) {
-		GoLog("[Tidal] Trying API: %s\n", reqURL)
+			reqStart := time.Now()
 
-		req, err := http.NewRequest("GET", reqURL, nil)
+			// Create client with timeout for parallel requests
-		if err != nil {
+			client := &http.Client{
-			errors = append(errors, BuildErrorMessage(apiURL, 0, err.Error()))
+				Timeout: 15 * time.Second,
-			continue
-		}
-
-		resp, err := DoRequestWithRetry(client, req, retryConfig)
-		if err != nil {
-			GoLog("[Tidal] API error: %v\n", err)
-			errors = append(errors, BuildErrorMessage(apiURL, 0, err.Error()))
-			continue
-		}
-
-		body, err := ReadResponseBody(resp)
-		resp.Body.Close()
-		if err != nil {
-			GoLog("[Tidal] Read body error: %v\n", err)
-			errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, err.Error()))
-			continue
-		}
-
-		// Log response preview
-		bodyPreview := string(body)
-		if len(bodyPreview) > 300 {
-			bodyPreview = bodyPreview[:300] + "..."
-		}
-		GoLog("[Tidal] API response (HTTP %d): %s\n", resp.StatusCode, bodyPreview)
-
-		// Try v2 format first (object with manifest)
-		var v2Response TidalAPIResponseV2
-		if err := json.Unmarshal(body, &v2Response); err == nil && v2Response.Data.Manifest != "" {
-			GoLog("[Tidal] Got v2 response from %s - Quality: %d-bit/%dHz, AssetPresentation: %s\n",
-				apiURL, v2Response.Data.BitDepth, v2Response.Data.SampleRate, v2Response.Data.AssetPresentation)
-
-			// IMPORTANT: Reject PREVIEW responses - we need FULL tracks
-			if v2Response.Data.AssetPresentation == "PREVIEW" {
-				GoLog("[Tidal] ✗ Rejecting PREVIEW response from %s, trying next API...\n", apiURL)
-				errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, "returned PREVIEW instead of FULL"))
-				continue
 			}
 
-			GoLog("[Tidal] ✓ Got FULL track from %s\n", apiURL)
+			reqURL := fmt.Sprintf("%s/track/?id=%d&quality=%s", api, trackID, quality)
-			info := TidalDownloadInfo{
-				URL:        "MANIFEST:" + v2Response.Data.Manifest,
-				BitDepth:   v2Response.Data.BitDepth,
-				SampleRate: v2Response.Data.SampleRate,
-			}
-			return apiURL, info, nil
-		}
 
-		// Fallback to v1 format (array with OriginalTrackUrl)
+			req, err := http.NewRequest("GET", reqURL, nil)
-		var v1Responses []struct {
+			if err != nil {
-			OriginalTrackURL string `json:"OriginalTrackUrl"`
+				resultChan <- tidalAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-		}
+				return
-		if err := json.Unmarshal(body, &v1Responses); err == nil {
+			}
-			for _, item := range v1Responses {
+
-				if item.OriginalTrackURL != "" {
+			resp, err := client.Do(req)
-					// v1 format doesn't have quality info, assume 16-bit/44.1kHz
+			if err != nil {
-					info := TidalDownloadInfo{
+				resultChan <- tidalAPIResult{apiURL: api, err: err, duration: time.Since(reqStart)}
-						URL:        item.OriginalTrackURL,
+				return
-						BitDepth:   16,
+			}
-						SampleRate: 44100,
+			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
+			}
+
+			// Try v2 format first (object with manifest)
+			var v2Response TidalAPIResponseV2
+			if err := json.Unmarshal(body, &v2Response); err == nil && v2Response.Data.Manifest != "" {
+				// IMPORTANT: Reject PREVIEW responses - we need FULL tracks
+				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
+			}
+
+			// Fallback to v1 format (array with OriginalTrackUrl)
+			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
 					}
-					return apiURL, info, nil
 				}
 			}
-		}
 
-		errors = append(errors, BuildErrorMessage(apiURL, resp.StatusCode, "no download URL or manifest in response"))
+			resultChan <- tidalAPIResult{apiURL: api, err: fmt.Errorf("no download URL or manifest in response"), duration: time.Since(reqStart)}
+		}(apiURL)
 	}
 
+	// Collect results - return first success
+	var errors []string
+
+	for i := 0; i < len(apis); i++ {
+		result := <-resultChan
+		if result.err == nil {
+			// First success - use this one
+			GoLog("[Tidal] [Parallel] ✓ Got response from %s (%d-bit/%dHz) in %v\n",
+				result.apiURL, result.info.BitDepth, result.info.SampleRate, result.duration)
+
+			// Don't return immediately - drain remaining results to avoid goroutine leaks
+			go func(remaining int) {
+				for j := 0; j < remaining; j++ {
+					<-resultChan
+				}
+			}(len(apis) - i - 1)
+
+			GoLog("[Tidal] [Parallel] Total time: %v (first success)\n", time.Since(startTime))
+			return result.apiURL, result.info, nil
+		}
+		errMsg := result.err.Error()
+		if len(errMsg) > 50 {
+			errMsg = errMsg[:50] + "..."
+		}
+		errors = append(errors, fmt.Sprintf("%s: %s", result.apiURL, errMsg))
+	}
+
+	GoLog("[Tidal] [Parallel] All %d APIs failed in %v\n", len(apis), time.Since(startTime))
 	return "", TidalDownloadInfo{}, fmt.Errorf("all %d Tidal APIs failed. Errors: %v", len(apis), errors)
 }
 
-// GetDownloadURL gets download URL for a track - tries APIs sequentially
+// GetDownloadURL gets download URL for a track - tries ALL APIs in parallel
+// "Siapa cepat dia dapat" - first successful response wins
 func (t *TidalDownloader) GetDownloadURL(trackID int64, quality string) (TidalDownloadInfo, error) {
 	apis := t.GetAvailableAPIs()
 	if len(apis) == 0 {
 		return TidalDownloadInfo{}, fmt.Errorf("no API URL configured")
 	}
 
-	_, info, err := getDownloadURLSequential(apis, trackID, quality)
+	// Use parallel approach - request from all APIs simultaneously
+	_, info, err := getDownloadURLParallel(apis, trackID, quality)
 	if err != nil {
 		return TidalDownloadInfo{}, fmt.Errorf("failed to get download URL: %w", err)
 	}
@@ -844,29 +888,45 @@ func parseManifest(manifestB64 string) (directURL string, initURL string, mediaU
 
 // DownloadFile downloads a file from URL with progress tracking
 func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) error {
+	ctx := context.Background()
+
 	// Handle manifest-based download (DASH/BTS)
 	if strings.HasPrefix(downloadURL, "MANIFEST:") {
 		// Initialize progress tracking for manifest downloads
 		if itemID != "" {
 			StartItemProgress(itemID)
 			defer CompleteItemProgress(itemID)
+			ctx = initDownloadCancel(itemID)
+			defer clearDownloadCancel(itemID)
 		}
-		return t.downloadFromManifest(strings.TrimPrefix(downloadURL, "MANIFEST:"), outputPath, itemID)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
+		return t.downloadFromManifest(ctx, strings.TrimPrefix(downloadURL, "MANIFEST:"), outputPath, itemID)
 	}
 
 	// Initialize item progress for direct downloads
 	if itemID != "" {
 		StartItemProgress(itemID)
 		defer CompleteItemProgress(itemID)
+		ctx = initDownloadCancel(itemID)
+		defer clearDownloadCancel(itemID)
 	}
 
-	req, err := http.NewRequest("GET", downloadURL, nil)
+	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(t.client, req)
 	if err != nil {
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		return err
 	}
 	defer resp.Body.Close()
@@ -906,6 +966,9 @@ func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 	// Check for any errors
 	if err != nil {
 		os.Remove(outputPath)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		return fmt.Errorf("download interrupted: %w", err)
 	}
 	if flushErr != nil {
@@ -926,7 +989,7 @@ func (t *TidalDownloader) DownloadFile(downloadURL, outputPath, itemID string) e
 	return nil
 }
 
-func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID string) error {
+func (t *TidalDownloader) downloadFromManifest(ctx context.Context, manifestB64, outputPath, itemID string) error {
 	fmt.Println("[Tidal] Parsing manifest...")
 	directURL, initURL, mediaURLs, err := parseManifest(manifestB64)
 	if err != nil {
@@ -945,7 +1008,11 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 		GoLog("[Tidal] BTS format - downloading from direct URL: %s...\n", directURL[:min(80, len(directURL))])
 		// Note: Progress tracking is initialized by the caller (DownloadFile)
 
-		req, err := http.NewRequest("GET", directURL, nil)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
+
+		req, err := http.NewRequestWithContext(ctx, "GET", directURL, nil)
 		if err != nil {
 			GoLog("[Tidal] BTS request creation failed: %v\n", err)
 			return fmt.Errorf("failed to create request: %w", err)
@@ -953,6 +1020,9 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 
 		resp, err := client.Do(req)
 		if err != nil {
+			if isDownloadCancelled(itemID) {
+				return ErrDownloadCancelled
+			}
 			GoLog("[Tidal] BTS download failed: %v\n", err)
 			return fmt.Errorf("failed to download file: %w", err)
 		}
@@ -988,6 +1058,9 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 
 		if err != nil {
 			os.Remove(outputPath)
+			if isDownloadCancelled(itemID) {
+				return ErrDownloadCancelled
+			}
 			return fmt.Errorf("download interrupted: %w", err)
 		}
 		if closeErr != nil {
@@ -1020,10 +1093,25 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 
 	// Download initialization segment
 	GoLog("[Tidal] Downloading init segment...\n")
-	resp, err := client.Get(initURL)
+	if isDownloadCancelled(itemID) {
+		out.Close()
+		os.Remove(m4aPath)
+		return ErrDownloadCancelled
+	}
+	req, err := http.NewRequestWithContext(ctx, "GET", initURL, nil)
 	if err != nil {
 		out.Close()
 		os.Remove(m4aPath)
+		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)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		GoLog("[Tidal] Init segment download failed: %v\n", err)
 		return fmt.Errorf("failed to download init segment: %w", err)
 	}
@@ -1039,6 +1127,9 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 	if err != nil {
 		out.Close()
 		os.Remove(m4aPath)
+		if isDownloadCancelled(itemID) {
+			return ErrDownloadCancelled
+		}
 		GoLog("[Tidal] Init segment write failed: %v\n", err)
 		return fmt.Errorf("failed to write init segment: %w", err)
 	}
@@ -1046,6 +1137,12 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 	// Download media segments with progress
 	totalSegments := len(mediaURLs)
 	for i, mediaURL := range mediaURLs {
+		if isDownloadCancelled(itemID) {
+			out.Close()
+			os.Remove(m4aPath)
+			return ErrDownloadCancelled
+		}
+
 		if i%10 == 0 || i == totalSegments-1 {
 			GoLog("[Tidal] Downloading segment %d/%d...\n", i+1, totalSegments)
 		}
@@ -1056,10 +1153,20 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 			SetItemProgress(itemID, progress, 0, 0)
 		}
 
-		resp, err := client.Get(mediaURL)
+		req, err := http.NewRequestWithContext(ctx, "GET", mediaURL, nil)
 		if err != nil {
 			out.Close()
 			os.Remove(m4aPath)
+			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)
+			if isDownloadCancelled(itemID) {
+				return ErrDownloadCancelled
+			}
 			GoLog("[Tidal] Segment %d download failed: %v\n", i+1, err)
 			return fmt.Errorf("failed to download segment %d: %w", i+1, err)
 		}
@@ -1075,6 +1182,9 @@ func (t *TidalDownloader) downloadFromManifest(manifestB64, outputPath, itemID s
 		if err != nil {
 			out.Close()
 			os.Remove(m4aPath)
+			if isDownloadCancelled(itemID) {
+				return ErrDownloadCancelled
+			}
 			GoLog("[Tidal] Segment %d write failed: %v\n", i+1, err)
 			return fmt.Errorf("failed to write segment %d: %w", i+1, err)
 		}
@@ -1119,24 +1229,27 @@ func artistsMatch(spotifyArtist, tidalArtist string) bool {
 		return true
 	}
 
-	// Check first artist (before comma or feat)
+	// Split artists by common separators (comma, feat, ft., &, and)
-	spotifyFirst := strings.Split(normSpotify, ",")[0]
+	// e.g., "RADWIMPS, Toko Miura" or "RADWIMPS feat. Toko Miura"
-	spotifyFirst = strings.Split(spotifyFirst, " feat")[0]
+	spotifyArtists := splitArtists(normSpotify)
-	spotifyFirst = strings.Split(spotifyFirst, " ft.")[0]
+	tidalArtists := splitArtists(normTidal)
-	spotifyFirst = strings.TrimSpace(spotifyFirst)
 
-	tidalFirst := strings.Split(normTidal, ",")[0]
+	// Check if ANY expected artist matches ANY found artist
-	tidalFirst = strings.Split(tidalFirst, " feat")[0]
+	for _, exp := range spotifyArtists {
-	tidalFirst = strings.Split(tidalFirst, " ft.")[0]
+		for _, fnd := range tidalArtists {
-	tidalFirst = strings.TrimSpace(tidalFirst)
+			if exp == fnd {
-
+				return true
-	if spotifyFirst == tidalFirst {
+			}
-		return true
+			// Also check contains for partial matches
-	}
+			if strings.Contains(exp, fnd) || strings.Contains(fnd, exp) {
-
+				return true
-	// Check if first artist is contained in the other
+			}
-	if strings.Contains(spotifyFirst, tidalFirst) || strings.Contains(tidalFirst, spotifyFirst) {
+			// Check same words different order
-		return true
+			if sameWordsUnordered(exp, fnd) {
+				GoLog("[Tidal] Artist names have same words in different order: '%s' vs '%s'\n", exp, fnd)
+				return true
+			}
+		}
 	}
 
 	// If scripts are TRULY different (Latin vs CJK/Arabic/Cyrillic), assume match (transliteration)
@@ -1152,6 +1265,67 @@ func artistsMatch(spotifyArtist, tidalArtist string) bool {
 	return false
 }
 
+// splitArtists splits artist string by common separators
+func splitArtists(artists string) []string {
+	// Replace common separators with a standard one
+	normalized := artists
+	normalized = strings.ReplaceAll(normalized, " feat. ", "|")
+	normalized = strings.ReplaceAll(normalized, " feat ", "|")
+	normalized = strings.ReplaceAll(normalized, " ft. ", "|")
+	normalized = strings.ReplaceAll(normalized, " ft ", "|")
+	normalized = strings.ReplaceAll(normalized, " & ", "|")
+	normalized = strings.ReplaceAll(normalized, " and ", "|")
+	normalized = strings.ReplaceAll(normalized, ", ", "|")
+	normalized = strings.ReplaceAll(normalized, " x ", "|")
+
+	parts := strings.Split(normalized, "|")
+	result := make([]string, 0, len(parts))
+	for _, p := range parts {
+		trimmed := strings.TrimSpace(p)
+		if trimmed != "" {
+			result = append(result, trimmed)
+		}
+	}
+	return result
+}
+
+// sameWordsUnordered checks if two strings have the same words regardless of order
+// Useful for Japanese names: "Sawano Hiroyuki" vs "Hiroyuki Sawano"
+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
+	}
+
+	// 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] {
+				sortedA[i], sortedA[j] = sortedA[j], sortedA[i]
+			}
+			if sortedB[i] > sortedB[j] {
+				sortedB[i], sortedB[j] = sortedB[j], sortedB[i]
+			}
+		}
+	}
+
+	for i := range sortedA {
+		if sortedA[i] != sortedB[i] {
+			return false
+		}
+	}
+	return true
+}
+
 // titlesMatch checks if track titles are similar enough
 func titlesMatch(expectedTitle, foundTitle string) bool {
 	normExpected := strings.ToLower(strings.TrimSpace(expectedTitle))
@@ -1326,14 +1500,15 @@ func isLatinScript(s string) bool {
 }
 
 // isASCIIString checks if a string contains only ASCII characters
-func isASCIIString(s string) bool {
+// Kept for potential future use
-	for _, r := range s {
+// func isASCIIString(s string) bool {
-		if r > 127 {
+// 	for _, r := range s {
-			return false
+// 		if r > 127 {
-		}
+// 			return false
-	}
+// 		}
-	return true
+// 	}
-}
+// 	return true
+// }
 
 // downloadFromTidal downloads a track using the request parameters
 func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
@@ -1350,8 +1525,24 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 	var track *TidalTrack
 	var err error
 
+	// STRATEGY 0: Use pre-fetched Tidal ID from Odesli enrichment (highest priority)
+	if req.TidalID != "" {
+		GoLog("[Tidal] Using Tidal ID from Odesli enrichment: %s\n", req.TidalID)
+		// Parse track ID (could be a number or extracted from URL)
+		var trackID int64
+		if _, parseErr := fmt.Sscanf(req.TidalID, "%d", &trackID); parseErr == nil && trackID > 0 {
+			track, err = downloader.GetTrackInfoByID(trackID)
+			if err != nil {
+				GoLog("[Tidal] Failed to get track by Odesli ID %d: %v\n", trackID, err)
+				track = nil
+			} else if track != nil {
+				GoLog("[Tidal] Successfully found track via Odesli ID: '%s' by '%s'\n", track.Title, track.Artist.Name)
+			}
+		}
+	}
+
 	// OPTIMIZATION: Check cache first for track ID
-	if req.ISRC != "" {
+	if track == nil && req.ISRC != "" {
 		if cached := GetTrackIDCache().Get(req.ISRC); cached != nil && cached.TidalTrackID > 0 {
 			GoLog("[Tidal] Cache hit! Using cached track ID: %d\n", cached.TidalTrackID)
 			track, err = downloader.GetTrackInfoByID(cached.TidalTrackID)
@@ -1385,7 +1576,7 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 		}
 	}
 
-	// Strategy 2: Try SongLink only if ISRC search failed (slower but more accurate)
+	// Strategy 2: Try SongLink if we have Spotify ID
 	if track == nil && req.SpotifyID != "" {
 		GoLog("[Tidal] ISRC search failed, trying SongLink...\n")
 		var tidalURL string
@@ -1563,6 +1754,9 @@ func downloadFromTidal(req DownloadRequest) (TidalDownloadResult, error) {
 	}())
 
 	if err := downloader.DownloadFile(downloadInfo.URL, outputPath, req.ItemID); err != nil {
+		if errors.Is(err, ErrDownloadCancelled) {
+			return TidalDownloadResult{}, ErrDownloadCancelled
+		}
 		GoLog("[Tidal] Download failed with error: %v\n", err)
 		return TidalDownloadResult{}, fmt.Errorf("download failed: %w", err)
 	}

ios/Runner/AppDelegate.swift

@@ -121,6 +121,12 @@ import Gobackend  // Import Go framework
             GobackendClearItemProgress(itemId)
             return nil
 
+        case "cancelDownload":
+            let args = call.arguments as! [String: Any]
+            let itemId = args["item_id"] as! String
+            GobackendCancelDownload(itemId)
+            return nil
+            
         case "setDownloadDirectory":
             let args = call.arguments as! [String: Any]
             let path = args["path"] as! String
@@ -256,6 +262,10 @@ import Gobackend  // Import Go framework
             GobackendSetSpotifyAPICredentials(clientId, clientSecret)
             return nil
             
+        case "hasSpotifyCredentials":
+            let hasCredentials = GobackendCheckSpotifyCredentials()
+            return hasCredentials
+            
         // Log methods
         case "getLogs":
             let response = GobackendGetLogs()
@@ -281,6 +291,303 @@ import Gobackend  // Import Go framework
             GobackendSetLoggingEnabled(enabled)
             return nil
             
+        // Extension System methods
+        case "initExtensionSystem":
+            let args = call.arguments as! [String: Any]
+            let extensionsDir = args["extensions_dir"] as! String
+            let dataDir = args["data_dir"] as! String
+            GobackendInitExtensionSystem(extensionsDir, dataDir, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "loadExtensionsFromDir":
+            let args = call.arguments as! [String: Any]
+            let dirPath = args["dir_path"] as! String
+            let response = GobackendLoadExtensionsFromDir(dirPath, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "loadExtensionFromPath":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let response = GobackendLoadExtensionFromPath(filePath, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "unloadExtension":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            GobackendUnloadExtensionByID(extensionId, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "getInstalledExtensions":
+            let response = GobackendGetInstalledExtensions(&error)
+            if let error = error { throw error }
+            return response
+            
+        case "setExtensionEnabled":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let enabled = args["enabled"] as? Bool ?? false
+            GobackendSetExtensionEnabledByID(extensionId, enabled, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "setProviderPriority":
+            let args = call.arguments as! [String: Any]
+            let priorityJson = args["priority"] as! String
+            GobackendSetProviderPriorityJSON(priorityJson, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "getProviderPriority":
+            let response = GobackendGetProviderPriorityJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        case "setMetadataProviderPriority":
+            let args = call.arguments as! [String: Any]
+            let priorityJson = args["priority"] as! String
+            GobackendSetMetadataProviderPriorityJSON(priorityJson, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "getMetadataProviderPriority":
+            let response = GobackendGetMetadataProviderPriorityJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        case "getExtensionSettings":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let response = GobackendGetExtensionSettingsJSON(extensionId, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "setExtensionSettings":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let settingsJson = args["settings"] as! String
+            GobackendSetExtensionSettingsJSON(extensionId, settingsJson, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "searchTracksWithExtensions":
+            let args = call.arguments as! [String: Any]
+            let query = args["query"] as! String
+            let limit = args["limit"] as? Int ?? 20
+            let response = GobackendSearchTracksWithExtensionsJSON(query, Int(limit), &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]
+            let extensionId = args["extension_id"] as! String
+            GobackendRemoveExtensionByID(extensionId, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "upgradeExtension":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let response = GobackendUpgradeExtensionFromPath(filePath, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "checkExtensionUpgrade":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let response = GobackendCheckExtensionUpgradeFromPath(filePath, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "cleanupExtensions":
+            GobackendCleanupExtensions()
+            return nil
+            
+        // Extension Auth API
+        case "getExtensionPendingAuth":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let response = GobackendGetExtensionPendingAuthJSON(extensionId, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "setExtensionAuthCode":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let authCode = args["auth_code"] as! String
+            GobackendSetExtensionAuthCodeByID(extensionId, authCode)
+            return nil
+            
+        case "setExtensionTokens":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let accessToken = args["access_token"] as! String
+            let refreshToken = args["refresh_token"] as? String ?? ""
+            let expiresIn = args["expires_in"] as? Int ?? 0
+            GobackendSetExtensionTokensByID(extensionId, accessToken, refreshToken, Int(expiresIn))
+            return nil
+            
+        case "clearExtensionPendingAuth":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            GobackendClearExtensionPendingAuthByID(extensionId)
+            return nil
+            
+        case "isExtensionAuthenticated":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let response = GobackendIsExtensionAuthenticatedByID(extensionId)
+            return response
+            
+        case "getAllPendingAuthRequests":
+            let response = GobackendGetAllPendingAuthRequestsJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        // Extension FFmpeg API
+        case "getPendingFFmpegCommand":
+            let args = call.arguments as! [String: Any]
+            let commandId = args["command_id"] as! String
+            let response = GobackendGetPendingFFmpegCommandJSON(commandId, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "setFFmpegCommandResult":
+            let args = call.arguments as! [String: Any]
+            let commandId = args["command_id"] as! String
+            let success = args["success"] as? Bool ?? false
+            let output = args["output"] as? String ?? ""
+            let errorMsg = args["error"] as? String ?? ""
+            GobackendSetFFmpegCommandResult(commandId, success, output, errorMsg)
+            return nil
+            
+        case "getAllPendingFFmpegCommands":
+            let response = GobackendGetAllPendingFFmpegCommandsJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        // Extension Custom Search API
+        case "customSearchWithExtension":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let query = args["query"] as! String
+            let optionsJson = args["options"] as? String ?? ""
+            let response = GobackendCustomSearchWithExtensionJSON(extensionId, query, optionsJson, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "getSearchProviders":
+            let response = GobackendGetSearchProvidersJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        // Extension URL Handler API
+        case "handleURLWithExtension":
+            let args = call.arguments as! [String: Any]
+            let url = args["url"] as! String
+            let response = GobackendHandleURLWithExtensionJSON(url, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "findURLHandler":
+            let args = call.arguments as! [String: Any]
+            let url = args["url"] as! String
+            let response = GobackendFindURLHandlerJSON(url)
+            return response
+            
+        case "getURLHandlers":
+            let response = GobackendGetURLHandlersJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        case "getAlbumWithExtension":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let albumId = args["album_id"] as! String
+            let response = GobackendGetAlbumWithExtensionJSON(extensionId, albumId, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "getPlaylistWithExtension":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let playlistId = args["playlist_id"] as! String
+            let response = GobackendGetPlaylistWithExtensionJSON(extensionId, playlistId, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "getArtistWithExtension":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let artistId = args["artist_id"] as! String
+            let response = GobackendGetArtistWithExtensionJSON(extensionId, artistId, &error)
+            if let error = error { throw error }
+            return response
+            
+        // Extension Post-Processing API
+        case "runPostProcessing":
+            let args = call.arguments as! [String: Any]
+            let filePath = args["file_path"] as! String
+            let metadataJson = args["metadata"] as? String ?? ""
+            let response = GobackendRunPostProcessingJSON(filePath, metadataJson, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "getPostProcessingProviders":
+            let response = GobackendGetPostProcessingProvidersJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        // Extension Store
+        case "initExtensionStore":
+            let args = call.arguments as! [String: Any]
+            let cacheDir = args["cache_dir"] as! String
+            GobackendInitExtensionStoreJSON(cacheDir, &error)
+            if let error = error { throw error }
+            return nil
+            
+        case "getStoreExtensions":
+            let args = call.arguments as! [String: Any]
+            let forceRefresh = args["force_refresh"] as? Bool ?? false
+            let response = GobackendGetStoreExtensionsJSON(forceRefresh, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "searchStoreExtensions":
+            let args = call.arguments as! [String: Any]
+            let query = args["query"] as? String ?? ""
+            let category = args["category"] as? String ?? ""
+            let response = GobackendSearchStoreExtensionsJSON(query, category, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "getStoreCategories":
+            let response = GobackendGetStoreCategoriesJSON(&error)
+            if let error = error { throw error }
+            return response
+            
+        case "downloadStoreExtension":
+            let args = call.arguments as! [String: Any]
+            let extensionId = args["extension_id"] as! String
+            let destDir = args["dest_dir"] as! String
+            let response = GobackendDownloadStoreExtensionJSON(extensionId, destDir, &error)
+            if let error = error { throw error }
+            return response
+            
+        case "clearStoreCache":
+            GobackendClearStoreCacheJSON(&error)
+            if let error = error { throw error }
+            return nil
+            
         default:
             throw NSError(
                 domain: "SpotiFLAC",

ios/Runner/Info.plist

@@ -4,6 +4,23 @@
 <dict>
 	<key>CFBundleDevelopmentRegion</key>
 	<string>$(DEVELOPMENT_LANGUAGE)</string>
+	<key>CFBundleLocalizations</key>
+	<array>
+		<string>en</string>
+		<string>de</string>
+		<string>es</string>
+		<string>fr</string>
+		<string>hi</string>
+		<string>id</string>
+		<string>ja</string>
+		<string>ko</string>
+		<string>nl</string>
+		<string>pt</string>
+		<string>ru</string>
+		<string>zh</string>
+		<string>zh-Hans</string>
+		<string>zh-Hant</string>
+	</array>
 	<key>CFBundleDisplayName</key>
 	<string>SpotiFLAC</string>
 	<key>CFBundleExecutable</key>

l10n.yaml

@@ -0,0 +1,6 @@
+arb-dir: lib/l10n/arb
+template-arb-file: app_en.arb
+output-localization-file: app_localizations.dart
+output-class: AppLocalizations
+output-dir: lib/l10n
+nullable-getter: false

lib/app.dart

@@ -1,10 +1,12 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+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/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) {
   // Only watch isFirstLaunch to prevent router rebuild on other settings changes
@@ -31,6 +33,13 @@ class SpotiFLACApp extends ConsumerWidget {
   @override
   Widget build(BuildContext context, WidgetRef ref) {
     final router = ref.watch(_routerProvider);
+    final localeString = ref.watch(settingsProvider.select((s) => s.locale));
+    
+    // Convert locale string to Locale object
+    Locale? locale;
+    if (localeString != 'system') {
+      locale = Locale(localeString);
+    }
     
     return DynamicColorWrapper(
       builder: (lightTheme, darkTheme, themeMode) {
@@ -43,6 +52,15 @@ class SpotiFLACApp extends ConsumerWidget {
           themeAnimationDuration: const Duration(milliseconds: 300),
           themeAnimationCurve: Curves.easeInOut,
           routerConfig: router,
+          // Localization
+          locale: locale, // null = follow system
+          localizationsDelegates: const [
+            AppLocalizations.delegate,
+            GlobalMaterialLocalizations.delegate,
+            GlobalWidgetsLocalizations.delegate,
+            GlobalCupertinoLocalizations.delegate,
+          ],
+          supportedLocales: AppLocalizations.supportedLocales,
         );
       },
     );

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 = '2.2.5';
+  static const String version = '3.1.0';
-  static const String buildNumber = '47';
+  static const String buildNumber = '59';
   static const String fullVersion = '$version+$buildNumber';
   
   

lib/l10n/arb/app_id.arb

@@ -0,0 +1,681 @@
+{
+  "@@locale": "id",
+  "@@last_modified": "2026-01-16",
+
+  "appName": "SpotiFLAC",
+  "appDescription": "Unduh lagu Spotify dalam kualitas lossless dari Tidal, Qobuz, dan Amazon Music.",
+
+  "navHome": "Beranda",
+  "navHistory": "Riwayat",
+  "navSettings": "Pengaturan",
+  "navStore": "Toko",
+
+  "homeTitle": "Beranda",
+  "homeSearchHint": "Tempel URL Spotify atau cari...",
+  "homeSearchHintExtension": "Cari dengan {extensionName}...",
+  "homeSubtitle": "Tempel link Spotify atau cari berdasarkan nama",
+  "homeSupports": "Mendukung: URL Track, Album, Playlist, Artis",
+  "homeRecent": "Terbaru",
+
+  "historyTitle": "Riwayat",
+  "historyDownloading": "Mengunduh ({count})",
+  "historyDownloaded": "Terunduh",
+  "historyFilterAll": "Semua",
+  "historyFilterAlbums": "Album",
+  "historyFilterSingles": "Single",
+  "historyTracksCount": "{count, plural, =1{1 lagu} other{{count} lagu}}",
+  "historyAlbumsCount": "{count, plural, =1{1 album} other{{count} album}}",
+  "historyNoDownloads": "Tidak ada riwayat unduhan",
+  "historyNoDownloadsSubtitle": "Lagu yang diunduh akan muncul di sini",
+  "historyNoAlbums": "Tidak ada unduhan album",
+  "historyNoAlbumsSubtitle": "Unduh beberapa lagu dari album untuk melihatnya di sini",
+  "historyNoSingles": "Tidak ada unduhan single",
+  "historyNoSinglesSubtitle": "Unduhan lagu satuan akan muncul di sini",
+
+  "settingsTitle": "Pengaturan",
+  "settingsDownload": "Unduhan",
+  "settingsAppearance": "Tampilan",
+  "settingsOptions": "Opsi",
+  "settingsExtensions": "Ekstensi",
+  "settingsAbout": "Tentang",
+
+  "downloadTitle": "Unduhan",
+  "downloadLocation": "Lokasi Unduhan",
+  "downloadLocationSubtitle": "Pilih tempat menyimpan file",
+  "downloadLocationDefault": "Lokasi default",
+  "downloadDefaultService": "Layanan Default",
+  "downloadDefaultServiceSubtitle": "Layanan yang digunakan untuk unduhan",
+  "downloadDefaultQuality": "Kualitas Default",
+  "downloadAskQuality": "Tanya Kualitas Sebelum Unduh",
+  "downloadAskQualitySubtitle": "Tampilkan pemilih kualitas untuk setiap unduhan",
+  "downloadFilenameFormat": "Format Nama File",
+  "downloadFolderOrganization": "Organisasi Folder",
+  "downloadSeparateSingles": "Pisahkan Single",
+  "downloadSeparateSinglesSubtitle": "Letakkan lagu satuan di folder terpisah",
+
+  "qualityBest": "Terbaik",
+  "qualityFlac": "FLAC",
+  "quality320": "320 kbps",
+  "quality128": "128 kbps",
+
+  "appearanceTitle": "Tampilan",
+  "appearanceTheme": "Tema",
+  "appearanceThemeSystem": "Sistem",
+  "appearanceThemeLight": "Terang",
+  "appearanceThemeDark": "Gelap",
+  "appearanceDynamicColor": "Warna Dinamis",
+  "appearanceDynamicColorSubtitle": "Gunakan warna dari wallpaper Anda",
+  "appearanceAccentColor": "Warna Aksen",
+  "appearanceHistoryView": "Tampilan Riwayat",
+  "appearanceHistoryViewList": "Daftar",
+  "appearanceHistoryViewGrid": "Grid",
+
+  "optionsTitle": "Opsi",
+  "optionsSearchSource": "Sumber Pencarian",
+  "optionsPrimaryProvider": "Provider Utama",
+  "optionsPrimaryProviderSubtitle": "Layanan yang digunakan saat mencari berdasarkan nama lagu.",
+  "optionsUsingExtension": "Menggunakan ekstensi: {extensionName}",
+  "optionsSwitchBack": "Ketuk Deezer atau Spotify untuk beralih dari ekstensi",
+  "optionsAutoFallback": "Auto Fallback",
+  "optionsAutoFallbackSubtitle": "Coba layanan lain jika unduhan gagal",
+  "optionsUseExtensionProviders": "Gunakan Provider Ekstensi",
+  "optionsUseExtensionProvidersOn": "Ekstensi akan dicoba terlebih dahulu",
+  "optionsUseExtensionProvidersOff": "Hanya menggunakan provider bawaan",
+  "optionsEmbedLyrics": "Sematkan Lirik",
+  "optionsEmbedLyricsSubtitle": "Sematkan lirik sinkron ke file FLAC",
+  "optionsMaxQualityCover": "Cover Kualitas Maksimal",
+  "optionsMaxQualityCoverSubtitle": "Unduh cover art resolusi tertinggi",
+  "optionsConcurrentDownloads": "Unduhan Bersamaan",
+  "optionsConcurrentSequential": "Berurutan (1 per waktu)",
+  "optionsConcurrentParallel": "{count} unduhan paralel",
+  "optionsConcurrentWarning": "Unduhan paralel dapat memicu pembatasan rate",
+  "optionsExtensionStore": "Toko Ekstensi",
+  "optionsExtensionStoreSubtitle": "Tampilkan tab Toko di navigasi",
+  "optionsCheckUpdates": "Periksa Pembaruan",
+  "optionsCheckUpdatesSubtitle": "Beritahu saat versi baru tersedia",
+  "optionsUpdateChannel": "Saluran Pembaruan",
+  "optionsUpdateChannelStable": "Hanya rilis stabil",
+  "optionsUpdateChannelPreview": "Dapatkan rilis preview",
+  "optionsUpdateChannelWarning": "Preview mungkin mengandung bug atau fitur belum lengkap",
+  "optionsClearHistory": "Hapus Riwayat Unduhan",
+  "optionsClearHistorySubtitle": "Hapus semua lagu dari riwayat",
+  "optionsDetailedLogging": "Log Detail",
+  "optionsDetailedLoggingOn": "Log detail sedang direkam",
+  "optionsDetailedLoggingOff": "Aktifkan untuk laporan bug",
+  "optionsSpotifyCredentials": "Kredensial Spotify",
+  "optionsSpotifyCredentialsConfigured": "Client ID: {clientId}...",
+  "optionsSpotifyCredentialsRequired": "Diperlukan - ketuk untuk mengatur",
+  "optionsSpotifyWarning": "Spotify memerlukan kredensial API Anda sendiri. Dapatkan gratis dari developer.spotify.com",
+
+  "extensionsTitle": "Ekstensi",
+  "extensionsInstalled": "Ekstensi Terpasang",
+  "extensionsNone": "Tidak ada ekstensi terpasang",
+  "extensionsNoneSubtitle": "Pasang ekstensi dari tab Toko",
+  "extensionsEnabled": "Aktif",
+  "extensionsDisabled": "Nonaktif",
+  "extensionsVersion": "Versi {version}",
+  "extensionsAuthor": "oleh {author}",
+  "extensionsUninstall": "Copot",
+  "extensionsSetAsSearch": "Jadikan Provider Pencarian",
+
+  "storeTitle": "Toko Ekstensi",
+  "storeSearch": "Cari ekstensi...",
+  "storeInstall": "Pasang",
+  "storeInstalled": "Terpasang",
+  "storeUpdate": "Perbarui",
+
+  "aboutTitle": "Tentang",
+  "aboutContributors": "Kontributor",
+  "aboutMobileDeveloper": "Pengembang versi mobile",
+  "aboutOriginalCreator": "Pencipta SpotiFLAC asli",
+  "aboutLogoArtist": "Seniman berbakat yang membuat logo aplikasi kami yang indah!",
+  "aboutSpecialThanks": "Terima Kasih Khusus",
+  "aboutLinks": "Tautan",
+  "aboutMobileSource": "Kode sumber mobile",
+  "aboutPCSource": "Kode sumber PC",
+  "aboutReportIssue": "Laporkan masalah",
+  "aboutReportIssueSubtitle": "Laporkan masalah yang Anda temui",
+  "aboutFeatureRequest": "Permintaan fitur",
+  "aboutFeatureRequestSubtitle": "Sarankan fitur baru untuk aplikasi",
+  "aboutSupport": "Dukungan",
+  "aboutBuyMeCoffee": "Traktir saya kopi",
+  "aboutBuyMeCoffeeSubtitle": "Dukung pengembangan di Ko-fi",
+  "aboutApp": "Aplikasi",
+  "aboutVersion": "Versi",
+
+  "albumTitle": "Album",
+  "albumTracks": "{count, plural, =1{1 lagu} other{{count} lagu}}",
+  "albumDownloadAll": "Unduh Semua",
+  "albumDownloadRemaining": "Unduh Sisanya",
+
+  "playlistTitle": "Playlist",
+  "artistTitle": "Artis",
+  "artistAlbums": "Album",
+  "artistSingles": "Single & EP",
+
+  "trackMetadataTitle": "Info Lagu",
+  "trackMetadataArtist": "Artis",
+  "trackMetadataAlbum": "Album",
+  "trackMetadataDuration": "Durasi",
+  "trackMetadataQuality": "Kualitas",
+  "trackMetadataPath": "Lokasi File",
+  "trackMetadataDownloadedAt": "Diunduh",
+  "trackMetadataService": "Layanan",
+  "trackMetadataPlay": "Putar",
+  "trackMetadataShare": "Bagikan",
+  "trackMetadataDelete": "Hapus",
+  "trackMetadataRedownload": "Unduh ulang",
+  "trackMetadataOpenFolder": "Buka Folder",
+
+  "setupTitle": "Selamat Datang di SpotiFLAC",
+  "setupSubtitle": "Mari mulai pengaturan",
+  "setupStoragePermission": "Izin Penyimpanan",
+  "setupStoragePermissionSubtitle": "Diperlukan untuk menyimpan file unduhan",
+  "setupStoragePermissionGranted": "Izin diberikan",
+  "setupStoragePermissionDenied": "Izin ditolak",
+  "setupGrantPermission": "Berikan Izin",
+  "setupDownloadLocation": "Lokasi Unduhan",
+  "setupChooseFolder": "Pilih Folder",
+  "setupContinue": "Lanjutkan",
+  "setupSkip": "Lewati untuk sekarang",
+
+  "dialogCancel": "Batal",
+  "dialogOk": "OK",
+  "dialogSave": "Simpan",
+  "dialogDelete": "Hapus",
+  "dialogRetry": "Coba Lagi",
+  "dialogClose": "Tutup",
+  "dialogYes": "Ya",
+  "dialogNo": "Tidak",
+  "dialogClear": "Hapus",
+  "dialogConfirm": "Konfirmasi",
+  "dialogDone": "Selesai",
+
+  "dialogClearHistoryTitle": "Hapus Riwayat",
+  "dialogClearHistoryMessage": "Apakah Anda yakin ingin menghapus semua riwayat unduhan? Ini tidak dapat dibatalkan.",
+  "dialogDeleteSelectedTitle": "Hapus yang Dipilih",
+  "dialogDeleteSelectedMessage": "Hapus {count} {count, plural, =1{lagu} other{lagu}} dari riwayat?\n\nIni juga akan menghapus file dari penyimpanan.",
+  "dialogImportPlaylistTitle": "Impor Playlist",
+  "dialogImportPlaylistMessage": "Ditemukan {count} lagu di CSV. Tambahkan ke antrian unduhan?",
+
+  "snackbarAddedToQueue": "Menambahkan \"{trackName}\" ke antrian",
+  "snackbarAddedTracksToQueue": "Menambahkan {count} lagu ke antrian",
+  "snackbarAlreadyDownloaded": "\"{trackName}\" sudah diunduh",
+  "snackbarHistoryCleared": "Riwayat dihapus",
+  "snackbarCredentialsSaved": "Kredensial disimpan",
+  "snackbarCredentialsCleared": "Kredensial dihapus",
+  "snackbarDeletedTracks": "Menghapus {count} {count, plural, =1{lagu} other{lagu}}",
+  "snackbarCannotOpenFile": "Tidak dapat membuka file: {error}",
+  "snackbarFillAllFields": "Harap isi semua field",
+  "snackbarViewQueue": "Lihat Antrian",
+
+  "errorRateLimited": "Dibatasi",
+  "errorRateLimitedMessage": "Terlalu banyak permintaan. Harap tunggu sebentar sebelum mencari lagi.",
+  "errorFailedToLoad": "Gagal memuat {item}",
+  "errorNoTracksFound": "Tidak ada lagu ditemukan",
+  "errorMissingExtensionSource": "Tidak dapat memuat {item}: sumber ekstensi tidak ada",
+
+  "statusQueued": "Mengantri",
+  "statusDownloading": "Mengunduh",
+  "statusFinalizing": "Menyelesaikan",
+  "statusCompleted": "Selesai",
+  "statusFailed": "Gagal",
+  "statusSkipped": "Dilewati",
+  "statusPaused": "Dijeda",
+
+  "actionPause": "Jeda",
+  "actionResume": "Lanjutkan",
+  "actionCancel": "Batal",
+  "actionStop": "Hentikan",
+  "actionSelect": "Pilih",
+  "actionSelectAll": "Pilih Semua",
+  "actionDeselect": "Batal Pilih",
+  "actionPaste": "Tempel",
+  "actionImportCsv": "Impor CSV",
+  "actionRemoveCredentials": "Hapus Kredensial",
+  "actionSaveCredentials": "Simpan Kredensial",
+
+  "selectionSelected": "{count} dipilih",
+  "selectionAllSelected": "Semua lagu dipilih",
+  "selectionTapToSelect": "Ketuk lagu untuk memilih",
+  "selectionDeleteTracks": "Hapus {count} {count, plural, =1{lagu} other{lagu}}",
+  "selectionSelectToDelete": "Pilih lagu untuk dihapus",
+
+  "progressFetchingMetadata": "Mengambil metadata... {current}/{total}",
+  "progressReadingCsv": "Membaca CSV...",
+
+  "searchSongs": "Lagu",
+  "searchArtists": "Artis",
+  "searchAlbums": "Album",
+  "searchPlaylists": "Playlist",
+
+  "tooltipPlay": "Putar",
+  "tooltipCancel": "Batal",
+  "tooltipStop": "Hentikan",
+  "tooltipRetry": "Coba Lagi",
+  "tooltipRemove": "Hapus",
+  "tooltipClear": "Hapus",
+  "tooltipPaste": "Tempel",
+
+  "filenameFormat": "Format Nama File",
+  "filenameFormatPreview": "Pratinjau: {preview}",
+  "folderOrganization": "Organisasi Folder",
+  "folderOrganizationNone": "Tanpa organisasi",
+  "folderOrganizationByArtist": "Berdasarkan Artis",
+  "folderOrganizationByAlbum": "Berdasarkan Album",
+  "folderOrganizationByArtistAlbum": "Artis/Album",
+
+  "updateAvailable": "Pembaruan Tersedia",
+  "updateNewVersion": "Versi {version} tersedia",
+  "updateDownload": "Unduh",
+  "updateLater": "Nanti",
+  "updateChangelog": "Log Perubahan",
+
+  "providerPriority": "Prioritas Provider",
+  "providerPrioritySubtitle": "Seret untuk mengatur ulang provider unduhan",
+  "metadataProviderPriority": "Prioritas Provider Metadata",
+  "metadataProviderPrioritySubtitle": "Urutan yang digunakan saat mengambil metadata lagu",
+
+  "logTitle": "Log",
+  "logCopy": "Salin Log",
+  "logClear": "Hapus Log",
+  "logShare": "Bagikan Log",
+  "logEmpty": "Belum ada log",
+  "logCopied": "Log disalin ke clipboard",
+
+  "credentialsTitle": "Kredensial Spotify",
+  "credentialsDescription": "Masukkan Client ID dan Secret Anda untuk menggunakan kuota aplikasi Spotify Anda sendiri.",
+  "credentialsClientId": "Client ID",
+  "credentialsClientIdHint": "Tempel Client ID",
+  "credentialsClientSecret": "Client Secret",
+  "credentialsClientSecretHint": "Tempel Client Secret",
+
+  "channelStable": "Stabil",
+  "channelPreview": "Preview",
+
+  "sectionSearchSource": "Sumber Pencarian",
+  "sectionDownload": "Unduhan",
+  "sectionPerformance": "Performa",
+  "sectionApp": "Aplikasi",
+  "sectionData": "Data",
+  "sectionDebug": "Debug",
+  "sectionService": "Layanan",
+  "sectionAudioQuality": "Kualitas Audio",
+  "sectionFileSettings": "Pengaturan File",
+  "sectionColor": "Warna",
+  "sectionTheme": "Tema",
+  "sectionLayout": "Tata Letak",
+  "sectionLanguage": "Bahasa",
+
+  "appearanceLanguage": "Bahasa Aplikasi",
+  "appearanceLanguageSubtitle": "Pilih bahasa yang kamu inginkan",
+  "languageSystem": "Bawaan Sistem",
+  "languageEnglish": "English",
+  "languageIndonesian": "Bahasa Indonesia",
+
+  "settingsAppearanceSubtitle": "Tema, warna, tampilan",
+  "settingsDownloadSubtitle": "Layanan, kualitas, format nama file",
+  "settingsOptionsSubtitle": "Fallback, lirik, cover art, pembaruan",
+  "settingsExtensionsSubtitle": "Kelola provider unduhan",
+  "settingsLogsSubtitle": "Lihat log aplikasi untuk debugging",
+
+  "loadingSharedLink": "Memuat link yang dibagikan...",
+  "pressBackAgainToExit": "Tekan kembali sekali lagi untuk keluar",
+
+  "artistReleases": "{count, plural, =1{1 rilis} other{{count} rilis}}",
+  "artistCompilations": "Kompilasi",
+  "artistPopular": "Populer",
+  "artistMonthlyListeners": "{count} pendengar bulanan",
+
+  "tracksHeader": "Lagu",
+  "downloadAllCount": "Unduh Semua ({count})",
+  "tracksCount": "{count, plural, =1{1 lagu} other{{count} lagu}}",
+
+  "setupStorageAccessRequired": "Akses Penyimpanan Diperlukan",
+  "setupStorageAccessMessage": "SpotiFLAC membutuhkan izin \"Akses semua file\" untuk menyimpan file musik ke folder pilihan Anda.",
+  "setupStorageAccessMessageAndroid11": "Android 11+ memerlukan izin \"Akses semua file\" untuk menyimpan file ke folder unduhan pilihan Anda.",
+  "setupOpenSettings": "Buka Pengaturan",
+  "setupPermissionDeniedMessage": "Izin ditolak. Harap berikan semua izin untuk melanjutkan.",
+  "setupPermissionRequired": "Izin {permissionType} Diperlukan",
+  "setupPermissionRequiredMessage": "Izin {permissionType} diperlukan untuk pengalaman terbaik. Anda dapat mengubahnya nanti di Pengaturan.",
+  "setupSelectDownloadFolder": "Pilih Folder Unduhan",
+  "setupUseDefaultFolder": "Gunakan Folder Default?",
+  "setupNoFolderSelected": "Tidak ada folder dipilih. Apakah Anda ingin menggunakan folder Musik default?",
+  "setupUseDefault": "Gunakan Default",
+  "setupDownloadLocationTitle": "Lokasi Unduhan",
+  "setupDownloadLocationIosMessage": "Di iOS, unduhan disimpan ke folder Documents aplikasi. Anda dapat mengaksesnya melalui aplikasi Files.",
+  "setupAppDocumentsFolder": "Folder Documents Aplikasi",
+  "setupAppDocumentsFolderSubtitle": "Direkomendasikan - dapat diakses via aplikasi Files",
+  "setupChooseFromFiles": "Pilih dari Files",
+  "setupChooseFromFilesSubtitle": "Pilih lokasi iCloud atau lainnya",
+  "setupIosEmptyFolderWarning": "Batasan iOS: Folder kosong tidak dapat dipilih. Pilih folder dengan minimal satu file.",
+  "setupDownloadInFlac": "Unduh lagu Spotify dalam format FLAC",
+  "setupStepStorage": "Penyimpanan",
+  "setupStepNotification": "Notifikasi",
+  "setupStepFolder": "Folder",
+  "setupStepSpotify": "Spotify",
+  "setupStepPermission": "Izin",
+  "setupStorageGranted": "Izin Penyimpanan Diberikan!",
+  "setupStorageRequired": "Izin Penyimpanan Diperlukan",
+  "setupStorageDescription": "SpotiFLAC membutuhkan izin penyimpanan untuk menyimpan file musik yang diunduh.",
+  "setupNotificationGranted": "Izin Notifikasi Diberikan!",
+  "setupNotificationEnable": "Aktifkan Notifikasi",
+  "setupNotificationDescription": "Dapatkan pemberitahuan saat unduhan selesai atau membutuhkan perhatian.",
+  "setupFolderSelected": "Folder Unduhan Dipilih!",
+  "setupFolderChoose": "Pilih Folder Unduhan",
+  "setupFolderDescription": "Pilih folder tempat musik yang diunduh akan disimpan.",
+  "setupChangeFolder": "Ubah Folder",
+  "setupSelectFolder": "Pilih Folder",
+  "setupSpotifyApiOptional": "Spotify API (Opsional)",
+  "setupSpotifyApiDescription": "Tambahkan kredensial Spotify API untuk hasil pencarian lebih baik dan akses ke konten eksklusif Spotify.",
+  "setupUseSpotifyApi": "Gunakan Spotify API",
+  "setupEnterCredentialsBelow": "Masukkan kredensial Anda di bawah",
+  "setupUsingDeezer": "Menggunakan Deezer (tidak perlu akun)",
+  "setupEnterClientId": "Masukkan Spotify Client ID",
+  "setupEnterClientSecret": "Masukkan Spotify Client Secret",
+  "setupGetFreeCredentials": "Dapatkan kredensial API gratis dari Spotify Developer Dashboard.",
+  "setupEnableNotifications": "Aktifkan Notifikasi",
+
+  "dialogImport": "Impor",
+  "dialogDiscard": "Buang",
+  "dialogRemove": "Hapus",
+  "dialogUninstall": "Copot",
+  "dialogDiscardChanges": "Buang Perubahan?",
+  "dialogUnsavedChanges": "Anda memiliki perubahan yang belum disimpan. Apakah Anda ingin membuangnya?",
+  "dialogDownloadFailed": "Unduhan Gagal",
+  "dialogTrackLabel": "Lagu:",
+  "dialogArtistLabel": "Artis:",
+  "dialogErrorLabel": "Error:",
+  "dialogClearAll": "Hapus Semua",
+  "dialogClearAllDownloads": "Apakah Anda yakin ingin menghapus semua unduhan?",
+  "dialogRemoveFromDevice": "Hapus dari perangkat?",
+  "dialogRemoveExtension": "Hapus Ekstensi",
+  "dialogRemoveExtensionMessage": "Apakah Anda yakin ingin menghapus ekstensi ini? Tindakan ini tidak dapat dibatalkan.",
+  "dialogUninstallExtension": "Copot Ekstensi?",
+  "dialogUninstallExtensionMessage": "Apakah Anda yakin ingin menghapus {extensionName}?",
+
+  "snackbarFailedToLoad": "Gagal memuat: {error}",
+  "snackbarUrlCopied": "URL {platform} disalin ke clipboard",
+  "snackbarFileNotFound": "File tidak ditemukan",
+  "snackbarSelectExtFile": "Harap pilih file .spotiflac-ext",
+  "snackbarProviderPrioritySaved": "Prioritas provider disimpan",
+  "snackbarMetadataProviderSaved": "Prioritas provider metadata disimpan",
+  "snackbarExtensionInstalled": "{extensionName} terpasang.",
+  "snackbarExtensionUpdated": "{extensionName} diperbarui.",
+  "snackbarFailedToInstall": "Gagal memasang ekstensi",
+  "snackbarFailedToUpdate": "Gagal memperbarui ekstensi",
+
+  "storeFilterAll": "Semua",
+  "storeFilterMetadata": "Metadata",
+  "storeFilterDownload": "Unduhan",
+  "storeFilterUtility": "Utilitas",
+  "storeFilterLyrics": "Lirik",
+  "storeFilterIntegration": "Integrasi",
+  "storeClearFilters": "Hapus filter",
+  "storeNoResults": "Tidak ada ekstensi ditemukan",
+
+  "extensionProviderPriority": "Prioritas Provider",
+  "extensionInstallButton": "Pasang Ekstensi",
+  "extensionDefaultProvider": "Default (Deezer/Spotify)",
+  "extensionDefaultProviderSubtitle": "Gunakan pencarian bawaan",
+  "extensionAuthor": "Pembuat",
+  "extensionId": "ID",
+  "extensionError": "Error",
+  "extensionCapabilities": "Kemampuan",
+  "extensionMetadataProvider": "Provider Metadata",
+  "extensionDownloadProvider": "Provider Unduhan",
+  "extensionLyricsProvider": "Provider Lirik",
+  "extensionUrlHandler": "Penanganan URL",
+  "extensionQualityOptions": "Opsi Kualitas",
+  "extensionPostProcessingHooks": "Hook Pasca-Pemrosesan",
+  "extensionPermissions": "Izin",
+  "extensionSettings": "Pengaturan",
+  "extensionRemoveButton": "Hapus Ekstensi",
+  "extensionUpdated": "Diperbarui",
+  "extensionMinAppVersion": "Versi App Minimum",
+
+  "qualityFlacLossless": "FLAC Lossless",
+  "qualityFlacLosslessSubtitle": "16-bit / 44.1kHz",
+  "qualityHiResFlac": "Hi-Res FLAC",
+  "qualityHiResFlacSubtitle": "24-bit / hingga 96kHz",
+  "qualityHiResFlacMax": "Hi-Res FLAC Max",
+  "qualityHiResFlacMaxSubtitle": "24-bit / hingga 192kHz",
+  "qualityNote": "Kualitas sebenarnya tergantung ketersediaan lagu dari layanan",
+
+  "downloadAskBeforeDownload": "Tanya Sebelum Unduh",
+  "downloadDirectory": "Direktori Unduhan",
+  "downloadSeparateSinglesFolder": "Folder Singles Terpisah",
+  "downloadAlbumFolderStructure": "Struktur Folder Album",
+  "downloadSaveFormat": "Simpan Format",
+  "downloadSelectService": "Pilih Layanan",
+  "downloadSelectQuality": "Pilih Kualitas",
+  "downloadFrom": "Unduh Dari",
+  "downloadDefaultQualityLabel": "Kualitas Default",
+  "downloadBestAvailable": "Terbaik tersedia",
+
+  "folderNone": "Tidak ada",
+  "folderNoneSubtitle": "Simpan semua file langsung ke folder unduhan",
+  "folderArtist": "Artis",
+  "folderArtistSubtitle": "Nama Artis/namafile",
+  "folderAlbum": "Album",
+  "folderAlbumSubtitle": "Nama Album/namafile",
+  "folderArtistAlbum": "Artis/Album",
+  "folderArtistAlbumSubtitle": "Nama Artis/Nama Album/namafile",
+
+  "serviceTidal": "Tidal",
+  "serviceQobuz": "Qobuz",
+  "serviceAmazon": "Amazon",
+  "serviceDeezer": "Deezer",
+  "serviceSpotify": "Spotify",
+
+  "logSearchHint": "Cari log...",
+  "logFilterLevel": "Level",
+  "logFilterSection": "Filter",
+  "logShareLogs": "Bagikan log",
+  "logClearLogs": "Hapus log",
+  "logClearLogsTitle": "Hapus Log",
+  "logClearLogsMessage": "Apakah Anda yakin ingin menghapus semua log?",
+  "logIspBlocking": "PEMBLOKIRAN ISP TERDETEKSI",
+  "logRateLimited": "DIBATASI",
+  "logNetworkError": "ERROR JARINGAN",
+  "logTrackNotFound": "LAGU TIDAK DITEMUKAN",
+
+  "appearanceAmoledDark": "AMOLED Gelap",
+  "appearanceAmoledDarkSubtitle": "Latar belakang hitam murni",
+  "appearanceChooseAccentColor": "Pilih Warna Aksen",
+  "appearanceChooseTheme": "Mode Tema",
+
+  "updateStartingDownload": "Memulai unduhan...",
+  "updateDownloadFailed": "Unduhan gagal",
+  "updateFailedMessage": "Gagal mengunduh pembaruan",
+  "updateNewVersionReady": "Versi baru sudah siap",
+  "updateCurrent": "Saat ini",
+  "updateNew": "Baru",
+  "updateDownloading": "Mengunduh...",
+  "updateWhatsNew": "Yang Baru",
+  "updateDownloadInstall": "Unduh & Pasang",
+  "updateDontRemind": "Jangan ingatkan",
+
+  "trackCopyFilePath": "Salin lokasi file",
+  "trackRemoveFromDevice": "Hapus dari perangkat",
+  "trackLoadLyrics": "Muat Lirik",
+
+  "dateToday": "Hari ini",
+  "dateYesterday": "Kemarin",
+  "dateDaysAgo": "{count} hari lalu",
+  "dateWeeksAgo": "{count} minggu lalu",
+  "dateMonthsAgo": "{count} bulan lalu",
+
+  "concurrentSequential": "Berurutan",
+  "concurrentParallel2": "2 Paralel",
+  "concurrentParallel3": "3 Paralel",
+
+  "filenameAvailablePlaceholders": "Placeholder yang tersedia:",
+  "filenameHint": "{artist} - {title}",
+
+  "tapToSeeError": "Ketuk untuk melihat detail error",
+
+  "setupProceedToNextStep": "Anda dapat melanjutkan ke langkah berikutnya.",
+  "setupNotificationProgressDescription": "Anda akan menerima notifikasi progres unduhan.",
+  "setupNotificationBackgroundDescription": "Dapatkan notifikasi tentang progres dan penyelesaian unduhan. Ini membantu Anda melacak unduhan saat aplikasi di latar belakang.",
+  "setupSkipForNow": "Lewati untuk sekarang",
+  "setupBack": "Kembali",
+  "setupNext": "Lanjut",
+  "setupGetStarted": "Mulai",
+  "setupSkipAndStart": "Lewati & Mulai",
+  "setupAllowAccessToManageFiles": "Harap aktifkan \"Izinkan akses untuk mengelola semua file\" di layar berikutnya.",
+  "setupGetCredentialsFromSpotify": "Dapatkan kredensial dari developer.spotify.com",
+
+  "trackMetadata": "Metadata",
+  "trackFileInfo": "Info File",
+  "trackLyrics": "Lirik",
+  "trackFileNotFound": "File tidak ditemukan",
+  "trackOpenInDeezer": "Buka di Deezer",
+  "trackOpenInSpotify": "Buka di Spotify",
+  "trackTrackName": "Nama lagu",
+  "trackArtist": "Artis",
+  "trackAlbumArtist": "Artis album",
+  "trackAlbum": "Album",
+  "trackTrackNumber": "Nomor lagu",
+  "trackDiscNumber": "Nomor disc",
+  "trackDuration": "Durasi",
+  "trackAudioQuality": "Kualitas audio",
+  "trackReleaseDate": "Tanggal rilis",
+  "trackDownloaded": "Diunduh",
+  "trackCopyLyrics": "Salin lirik",
+  "trackLyricsNotAvailable": "Lirik tidak tersedia untuk lagu ini",
+  "trackLyricsTimeout": "Permintaan timeout. Coba lagi nanti.",
+  "trackLyricsLoadFailed": "Gagal memuat lirik",
+  "trackCopiedToClipboard": "Disalin ke clipboard",
+  "trackDeleteConfirmTitle": "Hapus dari perangkat?",
+  "trackDeleteConfirmMessage": "Ini akan menghapus file unduhan secara permanen dan menghapusnya dari riwayat Anda.",
+  "trackCannotOpen": "Tidak dapat membuka: {message}",
+
+  "logFilterBySeverity": "Filter log berdasarkan tingkat keparahan",
+  "logNoLogsYet": "Belum ada log",
+  "logNoLogsYetSubtitle": "Log akan muncul di sini saat Anda menggunakan aplikasi",
+  "logIssueSummary": "Ringkasan Masalah",
+  "logIspBlockingDescription": "ISP Anda mungkin memblokir akses ke layanan unduhan",
+  "logIspBlockingSuggestion": "Coba gunakan VPN atau ubah DNS ke 1.1.1.1 atau 8.8.8.8",
+  "logRateLimitedDescription": "Terlalu banyak permintaan ke layanan",
+  "logRateLimitedSuggestion": "Tunggu beberapa menit sebelum mencoba lagi",
+  "logNetworkErrorDescription": "Masalah koneksi terdeteksi",
+  "logNetworkErrorSuggestion": "Periksa koneksi internet Anda",
+  "logTrackNotFoundDescription": "Beberapa lagu tidak dapat ditemukan di layanan unduhan",
+  "logTrackNotFoundSuggestion": "Lagu mungkin tidak tersedia dalam kualitas lossless",
+  "logTotalErrors": "Total error: {count}",
+  "logAffected": "Terpengaruh: {domains}",
+  "logEntriesFiltered": "Entri ({count} difilter)",
+  "logEntries": "Entri ({count})",
+
+  "extensionsProviderPrioritySection": "Prioritas Provider",
+  "extensionsInstalledSection": "Ekstensi Terpasang",
+  "extensionsNoExtensions": "Tidak ada ekstensi terpasang",
+  "extensionsNoExtensionsSubtitle": "Pasang file .spotiflac-ext untuk menambahkan provider baru",
+  "extensionsInstallButton": "Pasang Ekstensi",
+  "extensionsInfoTip": "Ekstensi dapat menambahkan provider metadata dan unduhan baru. Hanya pasang ekstensi dari sumber terpercaya.",
+  "extensionsInstalledSuccess": "Ekstensi berhasil dipasang",
+  "extensionsDownloadPriority": "Prioritas Unduhan",
+  "extensionsDownloadPrioritySubtitle": "Atur urutan layanan unduhan",
+  "extensionsNoDownloadProvider": "Tidak ada ekstensi dengan provider unduhan",
+  "extensionsMetadataPriority": "Prioritas Metadata",
+  "extensionsMetadataPrioritySubtitle": "Atur urutan sumber pencarian & metadata",
+  "extensionsNoMetadataProvider": "Tidak ada ekstensi dengan provider metadata",
+  "extensionsSearchProvider": "Provider Pencarian",
+  "extensionsNoCustomSearch": "Tidak ada ekstensi dengan pencarian kustom",
+  "extensionsSearchProviderDescription": "Pilih layanan yang digunakan untuk mencari lagu",
+  "extensionsCustomSearch": "Pencarian kustom",
+  "extensionsErrorLoading": "Error memuat ekstensi",
+
+  "extensionCustomTrackMatching": "Pencocokan Lagu Kustom",
+  "extensionPostProcessing": "Pasca-Pemrosesan",
+  "extensionHooksAvailable": "{count} hook tersedia",
+  "extensionPatternsCount": "{count} pola",
+  "extensionStrategy": "Strategi: {strategy}",
+
+  "aboutDoubleDouble": "DoubleDouble",
+  "aboutDoubleDoubleDesc": "API luar biasa untuk unduhan Amazon Music. Terima kasih sudah membuatnya gratis!",
+  "aboutDabMusic": "DAB Music",
+  "aboutDabMusicDesc": "API streaming Qobuz terbaik. Unduhan Hi-Res tidak akan mungkin tanpa ini!",
+
+  "queueTitle": "Antrian Unduhan",
+  "queueClearAll": "Hapus Semua",
+  "queueClearAllMessage": "Apakah Anda yakin ingin menghapus semua unduhan?",
+
+  "albumFolderArtistAlbum": "Artis / Album",
+  "albumFolderArtistAlbumSubtitle": "Albums/Nama Artis/Nama Album/",
+  "albumFolderArtistYearAlbum": "Artis / [Tahun] Album",
+  "albumFolderArtistYearAlbumSubtitle": "Albums/Nama Artis/[2005] Nama Album/",
+  "albumFolderAlbumOnly": "Album Saja",
+  "albumFolderAlbumOnlySubtitle": "Albums/Nama Album/",
+  "albumFolderYearAlbum": "[Tahun] Album",
+  "albumFolderYearAlbumSubtitle": "Albums/[2005] Nama Album/",
+
+  "downloadedAlbumDeleteSelected": "Hapus yang Dipilih",
+  "downloadedAlbumDeleteMessage": "Hapus {count} {count, plural, =1{lagu} other{lagu}} dari album ini?\n\nIni juga akan menghapus file dari penyimpanan.",
+
+  "utilityFunctions": "Fungsi Utilitas",
+
+  "aboutMobileDeveloper": "Pengembang versi mobile",
+  "aboutOriginalCreator": "Pembuat SpotiFLAC asli",
+  "aboutLogoArtist": "Seniman berbakat yang membuat logo aplikasi kita yang indah!",
+  "aboutBinimumDesc": "Pembuat QQDL & HiFi API. Tanpa API ini, unduhan Tidal tidak akan ada!",
+  "aboutSachinsenalDesc": "Pembuat proyek HiFi asli. Fondasi dari integrasi Tidal!",
+  "aboutMobileSource": "Kode sumber mobile",
+  "aboutPCSource": "Kode sumber PC",
+  "aboutReportIssue": "Laporkan masalah",
+  "aboutReportIssueSubtitle": "Laporkan masalah yang Anda temui",
+  "aboutFeatureRequest": "Permintaan fitur",
+  "aboutFeatureRequestSubtitle": "Sarankan fitur baru untuk aplikasi",
+  "aboutBuyMeCoffee": "Belikan saya kopi",
+  "aboutBuyMeCoffeeSubtitle": "Dukung pengembangan di Ko-fi",
+  "aboutVersion": "Versi",
+  "aboutAppDescription": "Unduh lagu Spotify dalam kualitas lossless dari Tidal, Qobuz, dan Amazon Music.",
+
+  "providerPriorityTitle": "Prioritas Provider",
+  "providerPriorityDescription": "Seret untuk mengatur ulang urutan provider unduhan. Aplikasi akan mencoba provider dari atas ke bawah saat mengunduh lagu.",
+  "providerPriorityInfo": "Jika lagu tidak tersedia di provider pertama, aplikasi akan otomatis mencoba yang berikutnya.",
+  "providerBuiltIn": "Bawaan",
+  "providerExtension": "Ekstensi",
+
+  "metadataProviderPriorityTitle": "Prioritas Metadata",
+  "metadataProviderPriorityDescription": "Seret untuk mengatur ulang urutan provider metadata. Aplikasi akan mencoba provider dari atas ke bawah saat mencari lagu dan mengambil metadata.",
+  "metadataProviderPriorityInfo": "Deezer tidak memiliki batas rate dan direkomendasikan sebagai utama. Spotify mungkin membatasi rate setelah banyak permintaan.",
+  "metadataNoRateLimits": "Tidak ada batas rate",
+  "metadataMayRateLimit": "Mungkin dibatasi rate",
+
+  "queueEmpty": "Tidak ada unduhan dalam antrian",
+  "queueEmptySubtitle": "Tambahkan lagu dari layar beranda",
+  "queueClearCompleted": "Hapus yang selesai",
+  "queueDownloadFailed": "Unduhan Gagal",
+  "queueTrackLabel": "Lagu:",
+  "queueArtistLabel": "Artis:",
+  "queueErrorLabel": "Error:",
+  "queueUnknownError": "Error tidak diketahui",
+
+  "downloadedAlbumTracksHeader": "Lagu",
+  "downloadedAlbumDownloadedCount": "{count} diunduh",
+  "downloadedAlbumSelectedCount": "{count} dipilih",
+  "downloadedAlbumAllSelected": "Semua lagu dipilih",
+  "downloadedAlbumTapToSelect": "Ketuk lagu untuk memilih",
+  "downloadedAlbumDeleteCount": "Hapus {count} {count, plural, =1{lagu} other{lagu}}",
+  "downloadedAlbumSelectToDelete": "Pilih lagu untuk dihapus",
+
+  "folderOrganizationDescription": "Atur file yang diunduh ke dalam folder",
+  "folderOrganizationNone": "Tidak ada",
+  "folderOrganizationNoneSubtitle": "Semua file di folder unduhan",
+  "folderOrganizationByArtist": "Berdasarkan Artis",
+  "folderOrganizationByArtistSubtitle": "Folder terpisah untuk setiap artis",
+  "folderOrganizationByAlbum": "Berdasarkan Album",
+  "folderOrganizationByAlbumSubtitle": "Folder terpisah untuk setiap album",
+  "folderOrganizationByArtistAlbum": "Berdasarkan Artis & Album",
+  "folderOrganizationByArtistAlbumSubtitle": "Folder bersarang untuk artis dan album",
+
+  "recentTypeArtist": "Artis",
+  "recentTypeAlbum": "Album",
+  "recentTypeSong": "Lagu",
+  "recentTypePlaylist": "Playlist",
+
+  "recentPlaylistInfo": "Playlist: {name}",
+  "errorGeneric": "Error: {message}"
+}

lib/l10n/l10n.dart

@@ -0,0 +1,11 @@
+import 'package:flutter/material.dart';
+import 'package:spotiflac_android/l10n/app_localizations.dart';
+
+export 'package:spotiflac_android/l10n/app_localizations.dart';
+
+/// Extension to easily access AppLocalizations from BuildContext
+extension AppLocalizationsX on BuildContext {
+  /// Get the AppLocalizations instance
+  /// Usage: context.l10n.navHome
+  AppLocalizations get l10n => AppLocalizations.of(this);
+}

lib/l10n/supported_locales.dart

@@ -0,0 +1,24 @@
+// GENERATED FILE - DO NOT EDIT
+// Generated by: dart run tool/check_translations.dart 70
+// Only languages with >= 70% translation completion are included.
+// Translation is measured by comparing VALUES (not just key existence).
+//
+// To regenerate, run: dart run tool/check_translations.dart 70
+
+import 'package:flutter/widgets.dart';
+
+/// Minimum translation completion threshold used to filter languages.
+const int translationThreshold = 70;
+
+/// List of locales that meet the translation threshold.
+/// Only these languages will be available in the app.
+const List<Locale> filteredSupportedLocales = <Locale>[
+  Locale('en'),
+  Locale('id'),
+];
+
+/// Set of locale codes for quick lookup.
+const Set<String> filteredLocaleCodes = <String>{
+  'en',
+  'id',
+};

lib/main.dart

@@ -1,7 +1,10 @@
+import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:path_provider/path_provider.dart';
 import 'package:spotiflac_android/app.dart';
 import 'package:spotiflac_android/providers/download_queue_provider.dart';
+import 'package:spotiflac_android/providers/extension_provider.dart';
 import 'package:spotiflac_android/services/notification_service.dart';
 import 'package:spotiflac_android/services/share_intent_service.dart';
 
@@ -24,14 +27,42 @@ void main() async {
 }
 
 /// Widget to eagerly initialize providers that need to load data on startup
-class _EagerInitialization extends ConsumerWidget {
+class _EagerInitialization extends ConsumerStatefulWidget {
   const _EagerInitialization({required this.child});
   final Widget child;
 
   @override
-  Widget build(BuildContext context, WidgetRef ref) {
+  ConsumerState<_EagerInitialization> createState() => _EagerInitializationState();
+}
+
+class _EagerInitializationState extends ConsumerState<_EagerInitialization> {
+  @override
+  void initState() {
+    super.initState();
+    _initializeExtensions();
+  }
+
+  Future<void> _initializeExtensions() async {
+    try {
+      final appDir = await getApplicationDocumentsDirectory();
+      final extensionsDir = '${appDir.path}/extensions';
+      final dataDir = '${appDir.path}/extension_data';
+      
+      // Create directories if needed
+      await Directory(extensionsDir).create(recursive: true);
+      await Directory(dataDir).create(recursive: true);
+      
+      // Initialize extension system
+      await ref.read(extensionProvider.notifier).initialize(extensionsDir, dataDir);
+    } catch (e) {
+      debugPrint('Failed to initialize extensions: $e');
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
     // Eagerly initialize download history provider to load from storage
     ref.watch(downloadHistoryProvider);
-    return child;
+    return widget.child;
   }
 }

lib/models/download_item.dart

@@ -19,6 +19,7 @@ enum DownloadErrorType {
   notFound,    // Track not found on any service
   rateLimit,   // Rate limited by service
   network,     // Network/connection error
+  permission,  // File/folder permission error
 }
 
 @JsonSerializable()
@@ -88,6 +89,8 @@ class DownloadItem {
         return 'Rate limit reached, try again later';
       case DownloadErrorType.network:
         return 'Connection failed, check your internet';
+      case DownloadErrorType.permission:
+        return 'Cannot write to folder, check storage permission';
       default:
         return error ?? 'An error occurred';
     }

lib/models/download_item.g.dart

@@ -51,4 +51,5 @@ const _$DownloadErrorTypeEnumMap = {
   DownloadErrorType.notFound: 'notFound',
   DownloadErrorType.rateLimit: 'rateLimit',
   DownloadErrorType.network: 'network',
+  DownloadErrorType.permission: 'permission',
 };

lib/models/settings.dart

@@ -18,12 +18,19 @@ class AppSettings {
   final bool hasSearchedBefore; // Hide helper text after first search
   final String folderOrganization; // none, artist, album, artist_album
   final String historyViewMode; // list, grid
+  final String historyFilterMode; // all, albums, singles
   final bool askQualityBeforeDownload; // Show quality picker before each download
   final String spotifyClientId; // Custom Spotify client ID (empty = use default)
   final String spotifyClientSecret; // Custom Spotify client secret (empty = use default)
   final bool useCustomSpotifyCredentials; // Whether to use custom credentials (if set)
   final String metadataSource; // spotify, deezer - source for search and metadata
   final bool enableLogging; // Enable detailed logging for debugging
+  final bool useExtensionProviders; // Use extension providers for downloads when available
+  final String? searchProvider; // null/empty = default (Deezer/Spotify), otherwise extension ID
+  final bool separateSingles; // Separate singles/EPs into their own folder
+  final String albumFolderStructure; // artist_album, album_only, artist_year_album, year_album
+  final bool showExtensionStore; // Show Extension Store tab in navigation
+  final String locale; // App language: 'system', 'en', 'id', etc.
 
   const AppSettings({
     this.defaultService = 'tidal',
@@ -40,12 +47,19 @@ class AppSettings {
     this.hasSearchedBefore = false, // Default: show helper text
     this.folderOrganization = 'none', // Default: no folder organization
     this.historyViewMode = 'grid', // Default: grid view
+    this.historyFilterMode = 'all', // Default: show all
     this.askQualityBeforeDownload = true, // Default: ask quality before download
     this.spotifyClientId = '', // Default: use built-in credentials
     this.spotifyClientSecret = '', // Default: use built-in credentials
     this.useCustomSpotifyCredentials = true, // Default: use custom if set
     this.metadataSource = 'deezer', // Default: Deezer (no rate limit)
     this.enableLogging = false, // Default: disabled for performance
+    this.useExtensionProviders = true, // Default: use extensions when available
+    this.searchProvider, // Default: null (use Deezer/Spotify)
+    this.separateSingles = false, // Default: disabled
+    this.albumFolderStructure = 'artist_album', // Default: Albums/Artist/Album
+    this.showExtensionStore = true, // Default: show store
+    this.locale = 'system', // Default: follow system language
   });
 
   AppSettings copyWith({
@@ -63,12 +77,20 @@ class AppSettings {
     bool? hasSearchedBefore,
     String? folderOrganization,
     String? historyViewMode,
+    String? historyFilterMode,
     bool? askQualityBeforeDownload,
     String? spotifyClientId,
     String? spotifyClientSecret,
     bool? useCustomSpotifyCredentials,
     String? metadataSource,
     bool? enableLogging,
+    bool? useExtensionProviders,
+    String? searchProvider,
+    bool clearSearchProvider = false, // Set to true to clear searchProvider to null
+    bool? separateSingles,
+    String? albumFolderStructure,
+    bool? showExtensionStore,
+    String? locale,
   }) {
     return AppSettings(
       defaultService: defaultService ?? this.defaultService,
@@ -85,12 +107,19 @@ class AppSettings {
       hasSearchedBefore: hasSearchedBefore ?? this.hasSearchedBefore,
       folderOrganization: folderOrganization ?? this.folderOrganization,
       historyViewMode: historyViewMode ?? this.historyViewMode,
+      historyFilterMode: historyFilterMode ?? this.historyFilterMode,
       askQualityBeforeDownload: askQualityBeforeDownload ?? this.askQualityBeforeDownload,
       spotifyClientId: spotifyClientId ?? this.spotifyClientId,
       spotifyClientSecret: spotifyClientSecret ?? this.spotifyClientSecret,
       useCustomSpotifyCredentials: useCustomSpotifyCredentials ?? this.useCustomSpotifyCredentials,
       metadataSource: metadataSource ?? this.metadataSource,
       enableLogging: enableLogging ?? this.enableLogging,
+      useExtensionProviders: useExtensionProviders ?? this.useExtensionProviders,
+      searchProvider: clearSearchProvider ? null : (searchProvider ?? this.searchProvider),
+      separateSingles: separateSingles ?? this.separateSingles,
+      albumFolderStructure: albumFolderStructure ?? this.albumFolderStructure,
+      showExtensionStore: showExtensionStore ?? this.showExtensionStore,
+      locale: locale ?? this.locale,
     );
   }
 

lib/models/settings.g.dart

@@ -21,6 +21,7 @@ AppSettings _$AppSettingsFromJson(Map<String, dynamic> json) => AppSettings(
   hasSearchedBefore: json['hasSearchedBefore'] as bool? ?? false,
   folderOrganization: json['folderOrganization'] as String? ?? 'none',
   historyViewMode: json['historyViewMode'] as String? ?? 'grid',
+  historyFilterMode: json['historyFilterMode'] as String? ?? 'all',
   askQualityBeforeDownload: json['askQualityBeforeDownload'] as bool? ?? true,
   spotifyClientId: json['spotifyClientId'] as String? ?? '',
   spotifyClientSecret: json['spotifyClientSecret'] as String? ?? '',
@@ -28,6 +29,13 @@ AppSettings _$AppSettingsFromJson(Map<String, dynamic> json) => AppSettings(
       json['useCustomSpotifyCredentials'] as bool? ?? true,
   metadataSource: json['metadataSource'] as String? ?? 'deezer',
   enableLogging: json['enableLogging'] as bool? ?? false,
+  useExtensionProviders: json['useExtensionProviders'] as bool? ?? true,
+  searchProvider: json['searchProvider'] as String?,
+  separateSingles: json['separateSingles'] as bool? ?? false,
+  albumFolderStructure:
+      json['albumFolderStructure'] as String? ?? 'artist_album',
+  showExtensionStore: json['showExtensionStore'] as bool? ?? true,
+  locale: json['locale'] as String? ?? 'system',
 );
 
 Map<String, dynamic> _$AppSettingsToJson(AppSettings instance) =>
@@ -46,10 +54,17 @@ Map<String, dynamic> _$AppSettingsToJson(AppSettings instance) =>
       'hasSearchedBefore': instance.hasSearchedBefore,
       'folderOrganization': instance.folderOrganization,
       'historyViewMode': instance.historyViewMode,
+      'historyFilterMode': instance.historyFilterMode,
       'askQualityBeforeDownload': instance.askQualityBeforeDownload,
       'spotifyClientId': instance.spotifyClientId,
       'spotifyClientSecret': instance.spotifyClientSecret,
       'useCustomSpotifyCredentials': instance.useCustomSpotifyCredentials,
       'metadataSource': instance.metadataSource,
       'enableLogging': instance.enableLogging,
+      'useExtensionProviders': instance.useExtensionProviders,
+      'searchProvider': instance.searchProvider,
+      'separateSingles': instance.separateSingles,
+      'albumFolderStructure': instance.albumFolderStructure,
+      'showExtensionStore': instance.showExtensionStore,
+      'locale': instance.locale,
     };

lib/models/track.dart

@@ -18,6 +18,9 @@ class Track {
   final String? releaseDate;
   final String? deezerId;
   final ServiceAvailability? availability;
+  final String? source; // Extension ID that provided this track (null for built-in sources)
+  final String? albumType; // album, single, ep, compilation (from metadata API)
+  final String? itemType; // track, album, playlist - for extension search results
 
   const Track({
     required this.id,
@@ -33,10 +36,31 @@ class Track {
     this.releaseDate,
     this.deezerId,
     this.availability,
+    this.source,
+    this.albumType,
+    this.itemType,
   });
 
+  /// Check if this track is a single (based on album_type metadata)
+  bool get isSingle => albumType == 'single' || albumType == 'ep';
+  
+  /// Check if this is an album item (not a track)
+  bool get isAlbumItem => itemType == 'album';
+  
+  /// Check if this is a playlist item (not a track)
+  bool get isPlaylistItem => itemType == 'playlist';
+  
+  /// Check if this is an artist item (not a track)
+  bool get isArtistItem => itemType == 'artist';
+  
+  /// Check if this is a collection (album, playlist, or artist)
+  bool get isCollection => isAlbumItem || isPlaylistItem || isArtistItem;
+
   factory Track.fromJson(Map<String, dynamic> json) => _$TrackFromJson(json);
   Map<String, dynamic> toJson() => _$TrackToJson(this);
+  
+  /// Check if this track is from an extension
+  bool get isFromExtension => source != null && source!.isNotEmpty;
 }
 
 @JsonSerializable()

lib/models/track.g.dart

@@ -24,6 +24,9 @@ Track _$TrackFromJson(Map<String, dynamic> json) => Track(
       : ServiceAvailability.fromJson(
           json['availability'] as Map<String, dynamic>,
         ),
+  source: json['source'] as String?,
+  albumType: json['albumType'] as String?,
+  itemType: json['itemType'] as String?,
 );
 
 Map<String, dynamic> _$TrackToJson(Track instance) => <String, dynamic>{
@@ -40,6 +43,9 @@ Map<String, dynamic> _$TrackToJson(Track instance) => <String, dynamic>{
   'releaseDate': instance.releaseDate,
   'deezerId': instance.deezerId,
   'availability': instance.availability,
+  'source': instance.source,
+  'albumType': instance.albumType,
+  'itemType': instance.itemType,
 };
 
 ServiceAvailability _$ServiceAvailabilityFromJson(Map<String, dynamic> json) =>

lib/providers/extension_provider.dart

@@ -0,0 +1,715 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:spotiflac_android/services/platform_bridge.dart';
+import 'package:spotiflac_android/utils/logger.dart';
+import 'package:spotiflac_android/providers/settings_provider.dart';
+
+final _log = AppLogger('ExtensionProvider');
+
+/// Represents an installed extension
+class Extension {
+  final String id;
+  final String name;
+  final String displayName;
+  final String version;
+  final String author;
+  final String description;
+  final bool enabled;
+  final String status; // 'loaded', 'error', 'disabled'
+  final String? errorMessage;
+  final String? iconPath; // Path to extension icon
+  final List<String> permissions;
+  final List<ExtensionSetting> settings;
+  final List<QualityOption> qualityOptions; // Custom quality options for download providers
+  final bool hasMetadataProvider;
+  final bool hasDownloadProvider;
+  final bool skipMetadataEnrichment; // If true, use metadata from extension instead of enriching
+  final SearchBehavior? searchBehavior; // Custom search behavior
+  final URLHandler? urlHandler; // Custom URL handling
+  final TrackMatching? trackMatching; // Custom track matching
+  final PostProcessing? postProcessing; // Post-processing hooks
+
+  const Extension({
+    required this.id,
+    required this.name,
+    required this.displayName,
+    required this.version,
+    required this.author,
+    required this.description,
+    required this.enabled,
+    required this.status,
+    this.errorMessage,
+    this.iconPath,
+    this.permissions = const [],
+    this.settings = const [],
+    this.qualityOptions = const [],
+    this.hasMetadataProvider = false,
+    this.hasDownloadProvider = false,
+    this.skipMetadataEnrichment = false,
+    this.searchBehavior,
+    this.urlHandler,
+    this.trackMatching,
+    this.postProcessing,
+  });
+
+  factory Extension.fromJson(Map<String, dynamic> json) {
+    return Extension(
+      id: json['id'] as String? ?? '',
+      name: json['name'] as String? ?? '',
+      displayName: json['display_name'] as String? ?? json['name'] as String? ?? '',
+      version: json['version'] as String? ?? '0.0.0',
+      author: json['author'] as String? ?? 'Unknown',
+      description: json['description'] as String? ?? '',
+      enabled: json['enabled'] as bool? ?? false,
+      status: json['status'] as String? ?? 'loaded',
+      errorMessage: json['error_message'] as String?,
+      iconPath: json['icon_path'] as String?,
+      permissions: (json['permissions'] as List<dynamic>?)?.cast<String>() ?? [],
+      settings: (json['settings'] as List<dynamic>?)
+          ?.map((s) => ExtensionSetting.fromJson(s as Map<String, dynamic>))
+          .toList() ?? [],
+      qualityOptions: (json['quality_options'] as List<dynamic>?)
+          ?.map((q) => QualityOption.fromJson(q as Map<String, dynamic>))
+          .toList() ?? [],
+      hasMetadataProvider: json['has_metadata_provider'] as bool? ?? false,
+      hasDownloadProvider: json['has_download_provider'] as bool? ?? false,
+      skipMetadataEnrichment: json['skip_metadata_enrichment'] as bool? ?? false,
+      searchBehavior: json['search_behavior'] != null 
+          ? SearchBehavior.fromJson(json['search_behavior'] as Map<String, dynamic>)
+          : null,
+      urlHandler: json['url_handler'] != null
+          ? URLHandler.fromJson(json['url_handler'] as Map<String, dynamic>)
+          : null,
+      trackMatching: json['track_matching'] != null
+          ? TrackMatching.fromJson(json['track_matching'] as Map<String, dynamic>)
+          : null,
+      postProcessing: json['post_processing'] != null
+          ? PostProcessing.fromJson(json['post_processing'] as Map<String, dynamic>)
+          : null,
+    );
+  }
+
+  Extension copyWith({
+    String? id,
+    String? name,
+    String? displayName,
+    String? version,
+    String? author,
+    String? description,
+    bool? enabled,
+    String? status,
+    String? errorMessage,
+    String? iconPath,
+    List<String>? permissions,
+    List<ExtensionSetting>? settings,
+    List<QualityOption>? qualityOptions,
+    bool? hasMetadataProvider,
+    bool? hasDownloadProvider,
+    bool? skipMetadataEnrichment,
+    SearchBehavior? searchBehavior,
+    URLHandler? urlHandler,
+    TrackMatching? trackMatching,
+    PostProcessing? postProcessing,
+  }) {
+    return Extension(
+      id: id ?? this.id,
+      name: name ?? this.name,
+      displayName: displayName ?? this.displayName,
+      version: version ?? this.version,
+      author: author ?? this.author,
+      description: description ?? this.description,
+      enabled: enabled ?? this.enabled,
+      status: status ?? this.status,
+      errorMessage: errorMessage ?? this.errorMessage,
+      iconPath: iconPath ?? this.iconPath,
+      permissions: permissions ?? this.permissions,
+      settings: settings ?? this.settings,
+      qualityOptions: qualityOptions ?? this.qualityOptions,
+      hasMetadataProvider: hasMetadataProvider ?? this.hasMetadataProvider,
+      hasDownloadProvider: hasDownloadProvider ?? this.hasDownloadProvider,
+      skipMetadataEnrichment: skipMetadataEnrichment ?? this.skipMetadataEnrichment,
+      searchBehavior: searchBehavior ?? this.searchBehavior,
+      urlHandler: urlHandler ?? this.urlHandler,
+      trackMatching: trackMatching ?? this.trackMatching,
+      postProcessing: postProcessing ?? this.postProcessing,
+    );
+  }
+
+  bool get hasCustomSearch => searchBehavior?.enabled ?? false;
+  bool get hasURLHandler => urlHandler?.enabled ?? false;
+  bool get hasCustomMatching => trackMatching?.customMatching ?? false;
+  bool get hasPostProcessing => postProcessing?.enabled ?? false;
+}
+
+/// Custom search behavior configuration
+class SearchBehavior {
+  final bool enabled;
+  final String? placeholder;
+  final bool primary;
+  final String? icon;
+  final String? thumbnailRatio; // "square" (1:1), "wide" (16:9), "portrait" (2:3)
+  final int? thumbnailWidth;
+  final int? thumbnailHeight;
+
+  const SearchBehavior({
+    required this.enabled,
+    this.placeholder,
+    this.primary = false,
+    this.icon,
+    this.thumbnailRatio,
+    this.thumbnailWidth,
+    this.thumbnailHeight,
+  });
+
+  factory SearchBehavior.fromJson(Map<String, dynamic> json) {
+    return SearchBehavior(
+      enabled: json['enabled'] as bool? ?? false,
+      placeholder: json['placeholder'] as String?,
+      primary: json['primary'] as bool? ?? false,
+      icon: json['icon'] as String?,
+      thumbnailRatio: json['thumbnailRatio'] as String?,
+      thumbnailWidth: json['thumbnailWidth'] as int?,
+      thumbnailHeight: json['thumbnailHeight'] as int?,
+    );
+  }
+
+  /// Get thumbnail size based on configuration
+  /// Returns (width, height) tuple
+  (double, double) getThumbnailSize({double defaultSize = 56}) {
+    // If custom dimensions specified, use them
+    if (thumbnailWidth != null && thumbnailHeight != null) {
+      return (thumbnailWidth!.toDouble(), thumbnailHeight!.toDouble());
+    }
+    
+    // Otherwise use ratio presets
+    switch (thumbnailRatio) {
+      case 'wide': // 16:9 - YouTube style
+        return (defaultSize * 16 / 9, defaultSize);
+      case 'portrait': // 2:3 - Poster style
+        return (defaultSize * 2 / 3, defaultSize);
+      case 'square': // 1:1 - Album art style
+      default:
+        return (defaultSize, defaultSize);
+    }
+  }
+}
+
+/// Custom track matching configuration
+class TrackMatching {
+  final bool customMatching;
+  final String? strategy; // "isrc", "name", "duration", "custom"
+  final int durationTolerance; // in seconds
+
+  const TrackMatching({
+    required this.customMatching,
+    this.strategy,
+    this.durationTolerance = 3,
+  });
+
+  factory TrackMatching.fromJson(Map<String, dynamic> json) {
+    return TrackMatching(
+      customMatching: json['customMatching'] as bool? ?? false,
+      strategy: json['strategy'] as String?,
+      durationTolerance: json['durationTolerance'] as int? ?? 3,
+    );
+  }
+}
+
+/// Post-processing configuration
+class PostProcessing {
+  final bool enabled;
+  final List<PostProcessingHook> hooks;
+
+  const PostProcessing({
+    required this.enabled,
+    this.hooks = const [],
+  });
+
+  factory PostProcessing.fromJson(Map<String, dynamic> json) {
+    return PostProcessing(
+      enabled: json['enabled'] as bool? ?? false,
+      hooks: (json['hooks'] as List<dynamic>?)
+          ?.map((h) => PostProcessingHook.fromJson(h as Map<String, dynamic>))
+          .toList() ?? [],
+    );
+  }
+}
+
+/// URL handler configuration for custom URL patterns
+class URLHandler {
+  final bool enabled;
+  final List<String> patterns;
+
+  const URLHandler({
+    required this.enabled,
+    this.patterns = const [],
+  });
+
+  factory URLHandler.fromJson(Map<String, dynamic> json) {
+    return URLHandler(
+      enabled: json['enabled'] as bool? ?? false,
+      patterns: (json['patterns'] as List<dynamic>?)?.cast<String>() ?? [],
+    );
+  }
+
+  /// Check if a URL matches any of the patterns
+  bool matchesURL(String url) {
+    if (!enabled || patterns.isEmpty) return false;
+    final lowerUrl = url.toLowerCase();
+    for (final pattern in patterns) {
+      if (lowerUrl.contains(pattern.toLowerCase())) {
+        return true;
+      }
+    }
+    return false;
+  }
+}
+
+/// A post-processing hook
+class PostProcessingHook {
+  final String id;
+  final String name;
+  final String? description;
+  final bool defaultEnabled;
+  final List<String> supportedFormats;
+
+  const PostProcessingHook({
+    required this.id,
+    required this.name,
+    this.description,
+    this.defaultEnabled = false,
+    this.supportedFormats = const [],
+  });
+
+  factory PostProcessingHook.fromJson(Map<String, dynamic> json) {
+    return PostProcessingHook(
+      id: json['id'] as String? ?? '',
+      name: json['name'] as String? ?? '',
+      description: json['description'] as String?,
+      defaultEnabled: json['defaultEnabled'] as bool? ?? false,
+      supportedFormats: (json['supportedFormats'] as List<dynamic>?)?.cast<String>() ?? [],
+    );
+  }
+}
+
+/// Represents a quality option for download providers
+class QualityOption {
+  final String id;
+  final String label;
+  final String? description;
+  final List<QualitySpecificSetting> settings; // Quality-specific settings
+
+  const QualityOption({
+    required this.id,
+    required this.label,
+    this.description,
+    this.settings = const [],
+  });
+
+  factory QualityOption.fromJson(Map<String, dynamic> json) {
+    return QualityOption(
+      id: json['id'] as String? ?? '',
+      label: json['label'] as String? ?? '',
+      description: json['description'] as String?,
+      settings: (json['settings'] as List<dynamic>?)
+          ?.map((s) => QualitySpecificSetting.fromJson(s as Map<String, dynamic>))
+          .toList() ?? [],
+    );
+  }
+}
+
+/// Represents a setting that's specific to a quality option
+class QualitySpecificSetting {
+  final String key;
+  final String label;
+  final String type; // 'string', 'number', 'boolean', 'select'
+  final dynamic defaultValue;
+  final String? description;
+  final List<String>? options; // For select type
+  final bool required;
+  final bool secret;
+
+  const QualitySpecificSetting({
+    required this.key,
+    required this.label,
+    required this.type,
+    this.defaultValue,
+    this.description,
+    this.options,
+    this.required = false,
+    this.secret = false,
+  });
+
+  factory QualitySpecificSetting.fromJson(Map<String, dynamic> json) {
+    return QualitySpecificSetting(
+      key: json['key'] as String? ?? '',
+      label: json['label'] as String? ?? '',
+      type: json['type'] as String? ?? 'string',
+      defaultValue: json['default'],
+      description: json['description'] as String?,
+      options: (json['options'] as List<dynamic>?)?.cast<String>(),
+      required: json['required'] as bool? ?? false,
+      secret: json['secret'] as bool? ?? false,
+    );
+  }
+}
+
+/// Represents a setting field for an extension
+class ExtensionSetting {
+  final String key;
+  final String label;
+  final String type; // 'string', 'number', 'boolean', 'select'
+  final dynamic defaultValue;
+  final String? description;
+  final List<String>? options; // For select type
+  final bool required;
+
+  const ExtensionSetting({
+    required this.key,
+    required this.label,
+    required this.type,
+    this.defaultValue,
+    this.description,
+    this.options,
+    this.required = false,
+  });
+
+  factory ExtensionSetting.fromJson(Map<String, dynamic> json) {
+    return ExtensionSetting(
+      key: json['key'] as String? ?? '',
+      label: json['label'] as String? ?? '',
+      type: json['type'] as String? ?? 'string',
+      defaultValue: json['default'],
+      description: json['description'] as String?,
+      options: (json['options'] as List<dynamic>?)?.cast<String>(),
+      required: json['required'] as bool? ?? false,
+    );
+  }
+}
+
+/// State for extension management
+class ExtensionState {
+  final List<Extension> extensions;
+  final List<String> providerPriority;
+  final List<String> metadataProviderPriority;
+  final bool isLoading;
+  final String? error;
+  final bool isInitialized;
+
+  const ExtensionState({
+    this.extensions = const [],
+    this.providerPriority = const [],
+    this.metadataProviderPriority = const [],
+    this.isLoading = false,
+    this.error,
+    this.isInitialized = false,
+  });
+
+  ExtensionState copyWith({
+    List<Extension>? extensions,
+    List<String>? providerPriority,
+    List<String>? metadataProviderPriority,
+    bool? isLoading,
+    String? error,
+    bool? isInitialized,
+  }) {
+    return ExtensionState(
+      extensions: extensions ?? this.extensions,
+      providerPriority: providerPriority ?? this.providerPriority,
+      metadataProviderPriority: metadataProviderPriority ?? this.metadataProviderPriority,
+      isLoading: isLoading ?? this.isLoading,
+      error: error,
+      isInitialized: isInitialized ?? this.isInitialized,
+    );
+  }
+}
+
+
+/// Provider for managing extensions
+class ExtensionNotifier extends Notifier<ExtensionState> {
+  @override
+  ExtensionState build() {
+    return const ExtensionState();
+  }
+
+  /// Initialize the extension system
+  Future<void> initialize(String extensionsDir, String dataDir) async {
+    if (state.isInitialized) return;
+    
+    state = state.copyWith(isLoading: true, error: null);
+    
+    try {
+      await PlatformBridge.initExtensionSystem(extensionsDir, dataDir);
+      await loadExtensions(extensionsDir);
+      await loadProviderPriority();
+      await loadMetadataProviderPriority();
+      state = state.copyWith(isInitialized: true, isLoading: false);
+      _log.i('Extension system initialized');
+    } catch (e) {
+      _log.e('Failed to initialize extension system: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+    }
+  }
+
+  /// Load all extensions from directory
+  Future<void> loadExtensions(String dirPath) async {
+    state = state.copyWith(isLoading: true, error: null);
+    
+    try {
+      final result = await PlatformBridge.loadExtensionsFromDir(dirPath);
+      _log.d('Load extensions result: $result');
+      await refreshExtensions();
+      state = state.copyWith(isLoading: false);
+    } catch (e) {
+      _log.e('Failed to load extensions: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+    }
+  }
+
+  /// Refresh the list of installed extensions
+  Future<void> refreshExtensions() async {
+    try {
+      final list = await PlatformBridge.getInstalledExtensions();
+      final extensions = list.map((e) => Extension.fromJson(e)).toList();
+      state = state.copyWith(extensions: extensions);
+      _log.d('Loaded ${extensions.length} extensions');
+      
+      // Log search behavior for extensions that have it
+      for (final ext in extensions) {
+        if (ext.searchBehavior != null) {
+          _log.d('Extension ${ext.id}: thumbnailRatio=${ext.searchBehavior!.thumbnailRatio}');
+        }
+      }
+    } catch (e) {
+      _log.e('Failed to refresh extensions: $e');
+      state = state.copyWith(error: e.toString());
+    }
+  }
+
+  /// Clear any error state
+  void clearError() {
+    state = state.copyWith(error: null);
+  }
+
+  /// Install extension from file (auto-upgrades if already installed with newer version)
+  Future<bool> installExtension(String filePath) async {
+    state = state.copyWith(isLoading: true, error: null);
+    
+    try {
+      final result = await PlatformBridge.loadExtensionFromPath(filePath);
+      _log.i('Installed extension: ${result['name']}');
+      await refreshExtensions();
+      state = state.copyWith(isLoading: false);
+      return true;
+    } catch (e) {
+      _log.e('Failed to install extension: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+      return false;
+    }
+  }
+
+  /// Check if a package file is an upgrade for an existing extension
+  /// Returns: {extension_id, current_version, new_version, can_upgrade, is_installed}
+  Future<Map<String, dynamic>> checkExtensionUpgrade(String filePath) async {
+    try {
+      return await PlatformBridge.checkExtensionUpgrade(filePath);
+    } catch (e) {
+      _log.e('Failed to check extension upgrade: $e');
+      return {'error': e.toString()};
+    }
+  }
+
+  /// Upgrade an existing extension from a new package file
+  Future<bool> upgradeExtension(String filePath) async {
+    state = state.copyWith(isLoading: true, error: null);
+    
+    try {
+      final result = await PlatformBridge.upgradeExtension(filePath);
+      _log.i('Upgraded extension: ${result['display_name']} to v${result['version']}');
+      await refreshExtensions();
+      state = state.copyWith(isLoading: false);
+      return true;
+    } catch (e) {
+      _log.e('Failed to upgrade extension: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+      return false;
+    }
+  }
+
+  /// Uninstall/remove an extension
+  Future<bool> removeExtension(String extensionId) async {
+    state = state.copyWith(isLoading: true, error: null);
+    
+    try {
+      await PlatformBridge.removeExtension(extensionId);
+      _log.i('Removed extension: $extensionId');
+      await refreshExtensions();
+      state = state.copyWith(isLoading: false);
+      return true;
+    } catch (e) {
+      _log.e('Failed to remove extension: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+      return false;
+    }
+  }
+
+  /// Enable or disable an extension
+  Future<void> setExtensionEnabled(String extensionId, bool enabled) async {
+    try {
+      await PlatformBridge.setExtensionEnabled(extensionId, enabled);
+      _log.d('Set extension $extensionId enabled: $enabled');
+      
+      // Get extension info before updating state
+      final ext = state.extensions.where((e) => e.id == extensionId).firstOrNull;
+      
+      // Update local state
+      final extensions = state.extensions.map((e) {
+        if (e.id == extensionId) {
+          return e.copyWith(enabled: enabled);
+        }
+        return e;
+      }).toList();
+      
+      state = state.copyWith(extensions: extensions);
+      
+      // If disabling an extension, reset related settings
+      if (!enabled && ext != null) {
+        final settings = ref.read(settingsProvider);
+        
+        // If this extension was the search provider, clear it and reset to Deezer
+        if (settings.searchProvider == extensionId) {
+          ref.read(settingsProvider.notifier).setSearchProvider(null);
+          ref.read(settingsProvider.notifier).setMetadataSource('deezer');
+          _log.d('Cleared search provider and reset to Deezer because extension $extensionId was disabled');
+        }
+        
+        // If this extension was the default download service, reset to Tidal
+        if (ext.hasDownloadProvider && settings.defaultService == extensionId) {
+          ref.read(settingsProvider.notifier).setDefaultService('tidal');
+          _log.d('Reset default service to Tidal because extension $extensionId was disabled');
+        }
+      }
+    } catch (e) {
+      _log.e('Failed to set extension enabled: $e');
+      state = state.copyWith(error: e.toString());
+    }
+  }
+
+  /// Get settings for an extension
+  Future<Map<String, dynamic>> getExtensionSettings(String extensionId) async {
+    try {
+      return await PlatformBridge.getExtensionSettings(extensionId);
+    } catch (e) {
+      _log.e('Failed to get extension settings: $e');
+      return {};
+    }
+  }
+
+  /// Update settings for an extension
+  Future<void> setExtensionSettings(String extensionId, Map<String, dynamic> settings) async {
+    try {
+      await PlatformBridge.setExtensionSettings(extensionId, settings);
+      _log.d('Updated settings for extension: $extensionId');
+    } catch (e) {
+      _log.e('Failed to set extension settings: $e');
+      state = state.copyWith(error: e.toString());
+    }
+  }
+
+  /// Load provider priority order
+  Future<void> loadProviderPriority() async {
+    try {
+      final priority = await PlatformBridge.getProviderPriority();
+      state = state.copyWith(providerPriority: priority);
+    } catch (e) {
+      _log.e('Failed to load provider priority: $e');
+    }
+  }
+
+  /// Set provider priority order
+  Future<void> setProviderPriority(List<String> priority) async {
+    try {
+      await PlatformBridge.setProviderPriority(priority);
+      state = state.copyWith(providerPriority: priority);
+      _log.d('Updated provider priority: $priority');
+    } catch (e) {
+      _log.e('Failed to set provider priority: $e');
+      state = state.copyWith(error: e.toString());
+    }
+  }
+
+  /// Load metadata provider priority order
+  Future<void> loadMetadataProviderPriority() async {
+    try {
+      final priority = await PlatformBridge.getMetadataProviderPriority();
+      state = state.copyWith(metadataProviderPriority: priority);
+    } catch (e) {
+      _log.e('Failed to load metadata provider priority: $e');
+    }
+  }
+
+  /// Set metadata provider priority order
+  Future<void> setMetadataProviderPriority(List<String> priority) async {
+    try {
+      await PlatformBridge.setMetadataProviderPriority(priority);
+      state = state.copyWith(metadataProviderPriority: priority);
+      _log.d('Updated metadata provider priority: $priority');
+    } catch (e) {
+      _log.e('Failed to set metadata provider priority: $e');
+      state = state.copyWith(error: e.toString());
+    }
+  }
+
+  /// Cleanup all extensions (call on app close)
+  Future<void> cleanup() async {
+    try {
+      await PlatformBridge.cleanupExtensions();
+      _log.d('Extensions cleaned up');
+    } catch (e) {
+      _log.e('Failed to cleanup extensions: $e');
+    }
+  }
+
+  /// Get extension by ID
+  Extension? getExtension(String extensionId) {
+    try {
+      return state.extensions.firstWhere((ext) => ext.id == extensionId);
+    } catch (_) {
+      return null;
+    }
+  }
+
+  /// Get all enabled extensions
+  List<Extension> get enabledExtensions {
+    return state.extensions.where((ext) => ext.enabled).toList();
+  }
+
+  /// Get all download providers (built-in + extensions)
+  List<String> getAllDownloadProviders() {
+    final providers = ['tidal', 'qobuz', 'amazon'];
+    for (final ext in state.extensions) {
+      if (ext.enabled && ext.hasDownloadProvider) {
+        providers.add(ext.id);
+      }
+    }
+    return providers;
+  }
+
+  /// Get all metadata providers (built-in + extensions)
+  List<String> getAllMetadataProviders() {
+    final providers = ['deezer', 'spotify'];
+    for (final ext in state.extensions) {
+      if (ext.enabled && ext.hasMetadataProvider) {
+        providers.add(ext.id);
+      }
+    }
+    return providers;
+  }
+  /// Get all extensions that provide custom search
+  List<Extension> get searchProviders {
+    return state.extensions.where((ext) => ext.enabled && ext.hasCustomSearch).toList();
+  }
+}
+
+final extensionProvider = NotifierProvider<ExtensionNotifier, ExtensionState>(
+  ExtensionNotifier.new,
+);

lib/providers/recent_access_provider.dart

@@ -0,0 +1,248 @@
+import 'dart:convert';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+const _recentAccessKey = 'recent_access_history';
+const _maxRecentItems = 20;
+
+/// Types of items that can be accessed
+enum RecentAccessType {
+  artist,
+  album,
+  track,
+  playlist,
+}
+
+/// Represents a recently accessed item
+class RecentAccessItem {
+  final String id;
+  final String name;
+  final String? subtitle; // Artist name for tracks/albums, null for artists
+  final String? imageUrl;
+  final RecentAccessType type;
+  final DateTime accessedAt;
+  final String? providerId; // Extension ID or 'deezer' for built-in
+
+  const RecentAccessItem({
+    required this.id,
+    required this.name,
+    this.subtitle,
+    this.imageUrl,
+    required this.type,
+    required this.accessedAt,
+    this.providerId,
+  });
+
+  Map<String, dynamic> toJson() => {
+    'id': id,
+    'name': name,
+    'subtitle': subtitle,
+    'imageUrl': imageUrl,
+    'type': type.name,
+    'accessedAt': accessedAt.toIso8601String(),
+    'providerId': providerId,
+  };
+
+  factory RecentAccessItem.fromJson(Map<String, dynamic> json) {
+    return RecentAccessItem(
+      id: json['id'] as String,
+      name: json['name'] as String,
+      subtitle: json['subtitle'] as String?,
+      imageUrl: json['imageUrl'] as String?,
+      type: RecentAccessType.values.firstWhere(
+        (e) => e.name == json['type'],
+        orElse: () => RecentAccessType.track,
+      ),
+      accessedAt: DateTime.parse(json['accessedAt'] as String),
+      providerId: json['providerId'] as String?,
+    );
+  }
+
+  /// Create a unique key for deduplication
+  String get uniqueKey => '${type.name}:${providerId ?? 'default'}:$id';
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is RecentAccessItem &&
+          runtimeType == other.runtimeType &&
+          uniqueKey == other.uniqueKey;
+
+  @override
+  int get hashCode => uniqueKey.hashCode;
+}
+
+/// State for recent access history
+class RecentAccessState {
+  final List<RecentAccessItem> items;
+  final bool isLoaded;
+
+  const RecentAccessState({
+    this.items = const [],
+    this.isLoaded = false,
+  });
+
+  RecentAccessState copyWith({
+    List<RecentAccessItem>? items,
+    bool? isLoaded,
+  }) {
+    return RecentAccessState(
+      items: items ?? this.items,
+      isLoaded: isLoaded ?? this.isLoaded,
+    );
+  }
+}
+
+/// Provider for managing recent access history
+class RecentAccessNotifier extends Notifier<RecentAccessState> {
+  @override
+  RecentAccessState build() {
+    _loadHistory();
+    return const RecentAccessState();
+  }
+
+  Future<void> _loadHistory() async {
+    final prefs = await SharedPreferences.getInstance();
+    final json = prefs.getString(_recentAccessKey);
+    if (json != null) {
+      try {
+        final List<dynamic> decoded = jsonDecode(json);
+        final items = decoded
+            .map((e) => RecentAccessItem.fromJson(e as Map<String, dynamic>))
+            .toList();
+        state = state.copyWith(items: items, isLoaded: true);
+      } catch (e) {
+        // Invalid JSON, start fresh
+        state = state.copyWith(isLoaded: true);
+      }
+    } else {
+      state = state.copyWith(isLoaded: true);
+    }
+  }
+
+  Future<void> _saveHistory() async {
+    final prefs = await SharedPreferences.getInstance();
+    final json = jsonEncode(state.items.map((e) => e.toJson()).toList());
+    await prefs.setString(_recentAccessKey, json);
+  }
+
+  /// Record an access to an artist
+  void recordArtistAccess({
+    required String id,
+    required String name,
+    String? imageUrl,
+    String? providerId,
+  }) {
+    _recordAccess(RecentAccessItem(
+      id: id,
+      name: name,
+      imageUrl: imageUrl,
+      type: RecentAccessType.artist,
+      accessedAt: DateTime.now(),
+      providerId: providerId,
+    ));
+  }
+
+  /// Record an access to an album
+  void recordAlbumAccess({
+    required String id,
+    required String name,
+    String? artistName,
+    String? imageUrl,
+    String? providerId,
+  }) {
+    _recordAccess(RecentAccessItem(
+      id: id,
+      name: name,
+      subtitle: artistName,
+      imageUrl: imageUrl,
+      type: RecentAccessType.album,
+      accessedAt: DateTime.now(),
+      providerId: providerId,
+    ));
+  }
+
+  /// Record an access to a track
+  void recordTrackAccess({
+    required String id,
+    required String name,
+    String? artistName,
+    String? imageUrl,
+    String? providerId,
+  }) {
+    _recordAccess(RecentAccessItem(
+      id: id,
+      name: name,
+      subtitle: artistName,
+      imageUrl: imageUrl,
+      type: RecentAccessType.track,
+      accessedAt: DateTime.now(),
+      providerId: providerId,
+    ));
+  }
+
+  /// Record an access to a playlist
+  void recordPlaylistAccess({
+    required String id,
+    required String name,
+    String? ownerName,
+    String? imageUrl,
+    String? providerId,
+  }) {
+    _recordAccess(RecentAccessItem(
+      id: id,
+      name: name,
+      subtitle: ownerName,
+      imageUrl: imageUrl,
+      type: RecentAccessType.playlist,
+      accessedAt: DateTime.now(),
+      providerId: providerId,
+    ));
+  }
+
+  void _recordAccess(RecentAccessItem item) {
+    // Debug log
+    // ignore: avoid_print
+    print('[RecentAccess] Recording: ${item.type.name} - ${item.name} (${item.id})');
+    
+    // Remove any existing entry with same unique key
+    final updatedItems = state.items
+        .where((e) => e.uniqueKey != item.uniqueKey)
+        .toList();
+    
+    // Add new item at the beginning
+    updatedItems.insert(0, item);
+    
+    // Limit to max items
+    if (updatedItems.length > _maxRecentItems) {
+      updatedItems.removeRange(_maxRecentItems, updatedItems.length);
+    }
+    
+    state = state.copyWith(items: updatedItems);
+    _saveHistory();
+    
+    // Debug log
+    // ignore: avoid_print
+    print('[RecentAccess] Total items now: ${updatedItems.length}');
+  }
+
+  /// Remove a specific item from history
+  void removeItem(RecentAccessItem item) {
+    final updatedItems = state.items
+        .where((e) => e.uniqueKey != item.uniqueKey)
+        .toList();
+    state = state.copyWith(items: updatedItems);
+    _saveHistory();
+  }
+
+  /// Clear all history
+  void clearHistory() {
+    state = state.copyWith(items: []);
+    _saveHistory();
+  }
+}
+
+/// Provider instance
+final recentAccessProvider = NotifierProvider<RecentAccessNotifier, RecentAccessState>(
+  RecentAccessNotifier.new,
+);

lib/providers/settings_provider.dart

@@ -60,18 +60,16 @@ class SettingsNotifier extends Notifier<AppSettings> {
 
   /// Apply current Spotify credentials to Go backend
   Future<void> _applySpotifyCredentials() async {
-    // Only apply custom credentials if enabled and both fields are set
+    // Only apply if both fields are set
-    if (state.useCustomSpotifyCredentials && 
+    if (state.spotifyClientId.isNotEmpty && 
-        state.spotifyClientId.isNotEmpty && 
         state.spotifyClientSecret.isNotEmpty) {
       await PlatformBridge.setSpotifyCredentials(
         state.spotifyClientId,
         state.spotifyClientSecret,
       );
-    } else {
-      // Clear to use default
-      await PlatformBridge.setSpotifyCredentials('', '');
     }
+    // Note: If credentials are empty, Spotify API will return error
+    // User should use Deezer as metadata source instead
   }
 
   void setDefaultService(String service) {
@@ -148,6 +146,11 @@ class SettingsNotifier extends Notifier<AppSettings> {
     _saveSettings();
   }
 
+  void setHistoryFilterMode(String mode) {
+    state = state.copyWith(historyFilterMode: mode);
+    _saveSettings();
+  }
+
   void setAskQualityBeforeDownload(bool enabled) {
     state = state.copyWith(askQualityBeforeDownload: enabled);
     _saveSettings();
@@ -192,12 +195,46 @@ class SettingsNotifier extends Notifier<AppSettings> {
     _saveSettings();
   }
 
+  void setSearchProvider(String? provider) {
+    if (provider == null || provider.isEmpty) {
+      state = state.copyWith(clearSearchProvider: true);
+    } else {
+      state = state.copyWith(searchProvider: provider);
+    }
+    _saveSettings();
+  }
+
   void setEnableLogging(bool enabled) {
     state = state.copyWith(enableLogging: enabled);
     _saveSettings();
     // Sync logging state to LogBuffer
     LogBuffer.loggingEnabled = enabled;
   }
+
+  void setUseExtensionProviders(bool enabled) {
+    state = state.copyWith(useExtensionProviders: enabled);
+    _saveSettings();
+  }
+
+  void setSeparateSingles(bool enabled) {
+    state = state.copyWith(separateSingles: enabled);
+    _saveSettings();
+  }
+
+  void setAlbumFolderStructure(String structure) {
+    state = state.copyWith(albumFolderStructure: structure);
+    _saveSettings();
+  }
+
+  void setShowExtensionStore(bool enabled) {
+    state = state.copyWith(showExtensionStore: enabled);
+    _saveSettings();
+  }
+
+  void setLocale(String locale) {
+    state = state.copyWith(locale: locale);
+    _saveSettings();
+  }
 }
 
 final settingsProvider = NotifierProvider<SettingsNotifier, AppSettings>(

lib/providers/store_provider.dart

@@ -0,0 +1,316 @@
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:spotiflac_android/constants/app_info.dart';
+import 'package:spotiflac_android/services/platform_bridge.dart';
+import 'package:spotiflac_android/utils/logger.dart';
+import 'package:spotiflac_android/providers/extension_provider.dart';
+
+final _log = AppLogger('StoreProvider');
+
+/// Compare two semantic version strings
+/// Returns: -1 if v1 < v2, 0 if equal, 1 if v1 > v2
+int compareVersions(String v1, String v2) {
+  final parts1 = v1.replaceAll(RegExp(r'^v'), '').split('.');
+  final parts2 = v2.replaceAll(RegExp(r'^v'), '').split('.');
+  
+  final maxLen = parts1.length > parts2.length ? parts1.length : parts2.length;
+  
+  for (var i = 0; i < maxLen; i++) {
+    final n1 = i < parts1.length ? (int.tryParse(parts1[i]) ?? 0) : 0;
+    final n2 = i < parts2.length ? (int.tryParse(parts2[i]) ?? 0) : 0;
+    
+    if (n1 < n2) return -1;
+    if (n1 > n2) return 1;
+  }
+  return 0;
+}
+
+/// Extension categories
+class StoreCategory {
+  static const String metadata = 'metadata';
+  static const String download = 'download';
+  static const String utility = 'utility';
+  static const String lyrics = 'lyrics';
+  static const String integration = 'integration';
+
+  static const List<String> all = [metadata, download, utility, lyrics, integration];
+
+  static String getDisplayName(String category) {
+    switch (category) {
+      case metadata:
+        return 'Metadata';
+      case download:
+        return 'Download';
+      case utility:
+        return 'Utility';
+      case lyrics:
+        return 'Lyrics';
+      case integration:
+        return 'Integration';
+      default:
+        return category;
+    }
+  }
+}
+
+/// Represents an extension in the store
+class StoreExtension {
+  final String id;
+  final String name;
+  final String displayName;
+  final String version;
+  final String author;
+  final String description;
+  final String downloadUrl;
+  final String? iconUrl;
+  final String category;
+  final List<String> tags;
+  final int downloads;
+  final String updatedAt;
+  final String? minAppVersion;
+  final bool isInstalled;
+  final String? installedVersion;
+  final bool hasUpdate;
+
+  const StoreExtension({
+    required this.id,
+    required this.name,
+    required this.displayName,
+    required this.version,
+    required this.author,
+    required this.description,
+    required this.downloadUrl,
+    this.iconUrl,
+    required this.category,
+    this.tags = const [],
+    this.downloads = 0,
+    required this.updatedAt,
+    this.minAppVersion,
+    this.isInstalled = false,
+    this.installedVersion,
+    this.hasUpdate = false,
+  });
+
+  factory StoreExtension.fromJson(Map<String, dynamic> json) {
+    return StoreExtension(
+      id: json['id'] as String? ?? '',
+      name: json['name'] as String? ?? '',
+      displayName: json['display_name'] as String? ?? json['name'] as String? ?? '',
+      version: json['version'] as String? ?? '0.0.0',
+      author: json['author'] as String? ?? 'Unknown',
+      description: json['description'] as String? ?? '',
+      downloadUrl: json['download_url'] as String? ?? '',
+      iconUrl: json['icon_url'] as String?,
+      category: json['category'] as String? ?? 'utility',
+      tags: (json['tags'] as List<dynamic>?)?.cast<String>() ?? [],
+      downloads: json['downloads'] as int? ?? 0,
+      updatedAt: json['updated_at'] as String? ?? '',
+      minAppVersion: json['min_app_version'] as String?,
+      isInstalled: json['is_installed'] as bool? ?? false,
+      installedVersion: json['installed_version'] as String?,
+      hasUpdate: json['has_update'] as bool? ?? false,
+    );
+  }
+
+  /// Check if this extension requires a higher app version than current
+  bool get requiresNewerApp {
+    if (minAppVersion == null || minAppVersion!.isEmpty) return false;
+    return compareVersions(minAppVersion!, AppInfo.version) > 0;
+  }
+}
+
+/// State for extension store
+class StoreState {
+  final List<StoreExtension> extensions;
+  final String? selectedCategory;
+  final String searchQuery;
+  final bool isLoading;
+  final bool isDownloading;
+  final String? downloadingId;
+  final String? error;
+  final bool isInitialized;
+
+  const StoreState({
+    this.extensions = const [],
+    this.selectedCategory,
+    this.searchQuery = '',
+    this.isLoading = false,
+    this.isDownloading = false,
+    this.downloadingId,
+    this.error,
+    this.isInitialized = false,
+  });
+
+  StoreState copyWith({
+    List<StoreExtension>? extensions,
+    String? selectedCategory,
+    bool clearCategory = false,
+    String? searchQuery,
+    bool? isLoading,
+    bool? isDownloading,
+    String? downloadingId,
+    bool clearDownloadingId = false,
+    String? error,
+    bool clearError = false,
+    bool? isInitialized,
+  }) {
+    return StoreState(
+      extensions: extensions ?? this.extensions,
+      selectedCategory: clearCategory ? null : (selectedCategory ?? this.selectedCategory),
+      searchQuery: searchQuery ?? this.searchQuery,
+      isLoading: isLoading ?? this.isLoading,
+      isDownloading: isDownloading ?? this.isDownloading,
+      downloadingId: clearDownloadingId ? null : (downloadingId ?? this.downloadingId),
+      error: clearError ? null : (error ?? this.error),
+      isInitialized: isInitialized ?? this.isInitialized,
+    );
+  }
+
+  /// Get filtered extensions based on category and search
+  List<StoreExtension> get filteredExtensions {
+    var result = extensions;
+
+    if (selectedCategory != null) {
+      result = result.where((e) => e.category == selectedCategory).toList();
+    }
+
+    if (searchQuery.isNotEmpty) {
+      final query = searchQuery.toLowerCase();
+      result = result.where((e) =>
+        e.name.toLowerCase().contains(query) ||
+        e.displayName.toLowerCase().contains(query) ||
+        e.description.toLowerCase().contains(query) ||
+        e.author.toLowerCase().contains(query) ||
+        e.tags.any((t) => t.toLowerCase().contains(query))
+      ).toList();
+    }
+
+    return result;
+  }
+
+  /// Count of extensions with updates available
+  int get updatesAvailableCount {
+    return extensions.where((e) => e.hasUpdate).length;
+  }
+}
+
+/// Provider for managing extension store
+class StoreNotifier extends Notifier<StoreState> {
+  @override
+  StoreState build() {
+    return const StoreState();
+  }
+
+  /// Initialize the store
+  Future<void> initialize(String cacheDir) async {
+    if (state.isInitialized) return;
+
+    state = state.copyWith(isLoading: true, clearError: true);
+
+    try {
+      await PlatformBridge.initExtensionStore(cacheDir);
+      await refresh();
+      state = state.copyWith(isInitialized: true, isLoading: false);
+      _log.i('Extension store initialized');
+    } catch (e) {
+      _log.e('Failed to initialize store: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+    }
+  }
+
+  /// Refresh extensions from store
+  Future<void> refresh({bool forceRefresh = false}) async {
+    state = state.copyWith(isLoading: true, clearError: true);
+
+    try {
+      final extensions = await PlatformBridge.getStoreExtensions(forceRefresh: forceRefresh);
+      state = state.copyWith(
+        extensions: extensions.map((e) => StoreExtension.fromJson(e)).toList(),
+        isLoading: false,
+      );
+      _log.d('Loaded ${state.extensions.length} extensions from store');
+    } catch (e) {
+      _log.e('Failed to refresh store: $e');
+      state = state.copyWith(isLoading: false, error: e.toString());
+    }
+  }
+
+  /// Set category filter
+  void setCategory(String? category) {
+    if (category == null) {
+      state = state.copyWith(clearCategory: true);
+    } else {
+      state = state.copyWith(selectedCategory: category);
+    }
+  }
+
+  /// Set search query
+  void setSearchQuery(String query) {
+    state = state.copyWith(searchQuery: query);
+  }
+
+  /// Clear search
+  void clearSearch() {
+    state = state.copyWith(searchQuery: '', clearCategory: true);
+  }
+
+  /// Download and install extension
+  Future<bool> installExtension(String extensionId, String tempDir, String extensionsDir) async {
+    state = state.copyWith(isDownloading: true, downloadingId: extensionId, clearError: true);
+
+    try {
+      _log.i('Downloading extension: $extensionId');
+      final downloadPath = await PlatformBridge.downloadStoreExtension(extensionId, tempDir);
+
+      _log.i('Installing extension from: $downloadPath');
+      final extNotifier = ref.read(extensionProvider.notifier);
+      final success = await extNotifier.installExtension(downloadPath);
+
+      if (success) {
+        _log.i('Extension installed: $extensionId');
+        await refresh();
+      }
+
+      state = state.copyWith(isDownloading: false, clearDownloadingId: true);
+      return success;
+    } catch (e) {
+      _log.e('Failed to install extension: $e');
+      state = state.copyWith(isDownloading: false, clearDownloadingId: true, error: e.toString());
+      return false;
+    }
+  }
+
+  /// Update an installed extension
+  Future<bool> updateExtension(String extensionId, String tempDir) async {
+    state = state.copyWith(isDownloading: true, downloadingId: extensionId, clearError: true);
+
+    try {
+      _log.i('Downloading update for: $extensionId');
+      final downloadPath = await PlatformBridge.downloadStoreExtension(extensionId, tempDir);
+
+      _log.i('Upgrading extension from: $downloadPath');
+      final extNotifier = ref.read(extensionProvider.notifier);
+      final success = await extNotifier.upgradeExtension(downloadPath);
+
+      if (success) {
+        _log.i('Extension updated: $extensionId');
+        await refresh();
+      }
+
+      state = state.copyWith(isDownloading: false, clearDownloadingId: true);
+      return success;
+    } catch (e) {
+      _log.e('Failed to update extension: $e');
+      state = state.copyWith(isDownloading: false, clearDownloadingId: true, error: e.toString());
+      return false;
+    }
+  }
+
+  /// Clear error
+  void clearError() {
+    state = state.copyWith(clearError: true);
+  }
+}
+
+final storeProvider = NotifierProvider<StoreNotifier, StoreState>(
+  StoreNotifier.new,
+);

lib/providers/track_provider.dart

@@ -1,6 +1,11 @@
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:spotiflac_android/models/track.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
+import 'package:spotiflac_android/utils/logger.dart';
+import 'package:spotiflac_android/providers/settings_provider.dart';
+import 'package:spotiflac_android/providers/extension_provider.dart';
+
+final _log = AppLogger('TrackProvider');
 
 class TrackState {
   final List<Track> tracks;
@@ -12,9 +17,14 @@ class TrackState {
   final String? artistId;
   final String? artistName;
   final String? coverUrl;
+  final String? headerImageUrl; // Artist header image for background
+  final int? monthlyListeners; // Artist monthly listeners
   final List<ArtistAlbum>? artistAlbums; // For artist page
+  final List<Track>? artistTopTracks; // Artist's popular tracks
   final List<SearchArtist>? searchArtists; // For search results
   final bool hasSearchText; // For back button handling
+  final bool isShowingRecentAccess; // For recent access mode
+  final String? searchExtensionId; // Extension ID used for current search results
 
   const TrackState({
     this.tracks = const [],
@@ -26,9 +36,14 @@ class TrackState {
     this.artistId,
     this.artistName,
     this.coverUrl,
+    this.headerImageUrl,
+    this.monthlyListeners,
     this.artistAlbums,
+    this.artistTopTracks,
     this.searchArtists,
     this.hasSearchText = false,
+    this.isShowingRecentAccess = false,
+    this.searchExtensionId,
   });
 
   bool get hasContent => tracks.isNotEmpty || artistAlbums != null || (searchArtists != null && searchArtists!.isNotEmpty);
@@ -43,9 +58,14 @@ class TrackState {
     String? artistId,
     String? artistName,
     String? coverUrl,
+    String? headerImageUrl,
+    int? monthlyListeners,
     List<ArtistAlbum>? artistAlbums,
+    List<Track>? artistTopTracks,
     List<SearchArtist>? searchArtists,
     bool? hasSearchText,
+    bool? isShowingRecentAccess,
+    String? searchExtensionId,
   }) {
     return TrackState(
       tracks: tracks ?? this.tracks,
@@ -57,9 +77,14 @@ class TrackState {
       artistId: artistId ?? this.artistId,
       artistName: artistName ?? this.artistName,
       coverUrl: coverUrl ?? this.coverUrl,
+      headerImageUrl: headerImageUrl ?? this.headerImageUrl,
+      monthlyListeners: monthlyListeners ?? this.monthlyListeners,
       artistAlbums: artistAlbums ?? this.artistAlbums,
+      artistTopTracks: artistTopTracks ?? this.artistTopTracks,
       searchArtists: searchArtists ?? this.searchArtists,
       hasSearchText: hasSearchText ?? this.hasSearchText,
+      isShowingRecentAccess: isShowingRecentAccess ?? this.isShowingRecentAccess,
+      searchExtensionId: searchExtensionId,
     );
   }
 }
@@ -73,6 +98,7 @@ class ArtistAlbum {
   final String? coverUrl;
   final String albumType; // album, single, compilation
   final String artists;
+  final String? providerId; // Extension ID if from extension
 
   const ArtistAlbum({
     required this.id,
@@ -82,6 +108,7 @@ class ArtistAlbum {
     this.coverUrl,
     required this.albumType,
     required this.artists,
+    this.providerId,
   });
 }
 
@@ -122,6 +149,67 @@ class TrackNotifier extends Notifier<TrackState> {
     state = TrackState(isLoading: true, hasSearchText: state.hasSearchText);
 
     try {
+      // First, check if any extension can handle this URL
+      final extensionHandler = await PlatformBridge.findURLHandler(url);
+      if (extensionHandler != null) {
+        _log.i('Found extension URL handler: $extensionHandler for URL: $url');
+        final result = await PlatformBridge.handleURLWithExtension(url);
+        if (!_isRequestValid(requestId)) return;
+        
+        if (result != null) {
+          final type = result['type'] as String?;
+          final extensionId = result['extension_id'] as String?;
+          
+          if (type == 'track' && result['track'] != null) {
+            final trackData = result['track'] as Map<String, dynamic>;
+            final track = _parseSearchTrack(trackData, source: extensionId);
+            state = TrackState(
+              tracks: [track],
+              isLoading: false,
+              coverUrl: track.coverUrl,
+              searchExtensionId: extensionId,
+            );
+            return;
+          } else if ((type == 'album' || type == 'playlist') && result['tracks'] != null) {
+            final trackList = result['tracks'] as List<dynamic>;
+            final tracks = trackList.map((t) => _parseSearchTrack(t as Map<String, dynamic>, source: extensionId)).toList();
+            state = TrackState(
+              tracks: tracks,
+              isLoading: false,
+              albumId: result['album']?['id'] as String?,
+              albumName: result['name'] as String? ?? result['album']?['name'] as String?,
+              playlistName: type == 'playlist' ? result['name'] as String? : null,
+              coverUrl: result['cover_url'] as String?,
+              searchExtensionId: extensionId,
+            );
+            return;
+          } else if (type == 'artist' && result['artist'] != null) {
+            final artistData = result['artist'] as Map<String, dynamic>;
+            final albumsList = artistData['albums'] as List<dynamic>? ?? [];
+            final albums = albumsList.map((a) => _parseArtistAlbum(a as Map<String, dynamic>)).toList();
+            
+            // Parse top tracks if available
+            final topTracksList = artistData['top_tracks'] as List<dynamic>? ?? [];
+            final topTracks = topTracksList.map((t) => _parseSearchTrack(t as Map<String, dynamic>, source: extensionId)).toList();
+            
+            state = TrackState(
+              tracks: [],
+              isLoading: false,
+              artistId: artistData['id'] as String?,
+              artistName: artistData['name'] as String?,
+              coverUrl: artistData['image_url'] as String? ?? artistData['images'] as String?,
+              headerImageUrl: artistData['header_image'] as String?,
+              monthlyListeners: artistData['listeners'] as int?,
+              artistAlbums: albums,
+              artistTopTracks: topTracks.isNotEmpty ? topTracks : null,
+              searchExtensionId: extensionId,
+            );
+            return;
+          }
+        }
+      }
+      
+      // No extension handler found, try Spotify URL parsing
       final parsed = await PlatformBridge.parseSpotifyUrl(url);
       if (!_isRequestValid(requestId)) return; // Request cancelled
       
@@ -207,57 +295,116 @@ class TrackNotifier extends Notifier<TrackState> {
     state = TrackState(isLoading: true, hasSearchText: state.hasSearchText);
 
     try {
+      // Check if extension providers should be used for search
+      final settings = ref.read(settingsProvider);
+      final extensionState = ref.read(extensionProvider);
+      final hasActiveMetadataExtensions = extensionState.extensions.any(
+        (e) => e.enabled && e.hasMetadataProvider,
+      );
+      final searchProvider = settings.searchProvider;
+      final useExtensions =
+          settings.useExtensionProviders &&
+          hasActiveMetadataExtensions &&
+          searchProvider != null &&
+          searchProvider.isNotEmpty;
+
       // Use Deezer or Spotify based on settings
       final source = metadataSource ?? 'deezer';
       
-      // Debug log to show which source is being used
+      _log.i(
-      // ignore: avoid_print
+        'Search started: source=$source, query="$query", useExtensions=$useExtensions',
-      print('[Search] Using metadata source: $source for query: "$query"');
+      );
       
       Map<String, dynamic> results;
-      if (source == 'deezer') {
+      List<Track> extensionTracks = [];
-        results = await PlatformBridge.searchDeezerAll(query, trackLimit: 20, artistLimit: 5);
+      
-        // ignore: avoid_print
+      // Try extension providers first if enabled
-        print('[Search] Deezer returned ${(results['tracks'] as List?)?.length ?? 0} tracks');
+      if (useExtensions) {
-      } else {
+        try {
-        results = await PlatformBridge.searchSpotifyAll(query, trackLimit: 20, artistLimit: 5);
+          _log.d('Calling extension search API...');
-        // ignore: avoid_print
+          final extResults = await PlatformBridge.searchTracksWithExtensions(query, limit: 20);
-        print('[Search] Spotify returned ${(results['tracks'] as List?)?.length ?? 0} tracks');
+          _log.i('Extensions returned ${extResults.length} tracks');
+          
+          // Parse extension results
+          for (final t in extResults) {
+            try {
+              extensionTracks.add(_parseSearchTrack(t));
+            } catch (e) {
+              _log.e('Failed to parse extension track: $e', e);
+            }
+          }
+        } catch (e) {
+          _log.w('Extension search failed, falling back to built-in: $e');
+        }
       }
       
-      if (!_isRequestValid(requestId)) return; // Request cancelled
+      // Also search with built-in providers
+      if (source == 'deezer') {
+        _log.d('Calling Deezer search API...');
+        results = await PlatformBridge.searchDeezerAll(query, trackLimit: 20, artistLimit: 5);
+        _log.i('Deezer returned ${(results['tracks'] as List?)?.length ?? 0} tracks, ${(results['artists'] as List?)?.length ?? 0} artists');
+      } else {
+        _log.d('Calling Spotify search API...');
+        results = await PlatformBridge.searchSpotifyAll(query, trackLimit: 20, artistLimit: 5);
+        _log.i('Spotify returned ${(results['tracks'] as List?)?.length ?? 0} tracks, ${(results['artists'] as List?)?.length ?? 0} artists');
+      }
+      
+      if (!_isRequestValid(requestId)) {
+        _log.w('Search request cancelled (requestId=$requestId)');
+        return;
+      }
       
       final trackList = results['tracks'] as List<dynamic>? ?? [];
       final artistList = results['artists'] as List<dynamic>? ?? [];
       
+      _log.d('Raw results: ${trackList.length} tracks, ${artistList.length} artists');
+      
       // Parse tracks with error handling per item
       final tracks = <Track>[];
-      for (final t in trackList) {
+      
+      // Add extension tracks first (they have priority)
+      tracks.addAll(extensionTracks);
+      
+      // Add built-in provider tracks, avoiding duplicates by ISRC
+      final existingIsrcs = extensionTracks
+          .where((t) => t.isrc != null && t.isrc!.isNotEmpty)
+          .map((t) => t.isrc!)
+          .toSet();
+      
+      for (int i = 0; i < trackList.length; i++) {
+        final t = trackList[i];
         try {
           if (t is Map<String, dynamic>) {
-            tracks.add(_parseSearchTrack(t));
+            final track = _parseSearchTrack(t);
+            // Skip if we already have this track from extensions
+            if (track.isrc != null && existingIsrcs.contains(track.isrc)) {
+              continue;
+            }
+            tracks.add(track);
+          } else {
+            _log.w('Track[$i] is not a Map: ${t.runtimeType}');
           }
         } catch (e) {
-          // ignore: avoid_print
+          _log.e('Failed to parse track[$i]: $e', e);
-          print('[Search] Failed to parse track: $e');
         }
       }
       
       // Parse artists with error handling per item
       final artists = <SearchArtist>[];
-      for (final a in artistList) {
+      for (int i = 0; i < artistList.length; i++) {
+        final a = artistList[i];
         try {
           if (a is Map<String, dynamic>) {
             artists.add(_parseSearchArtist(a));
+          } else {
+            _log.w('Artist[$i] is not a Map: ${a.runtimeType}');
           }
         } catch (e) {
-          // ignore: avoid_print
+          _log.e('Failed to parse artist[$i]: $e', e);
-          print('[Search] Failed to parse artist: $e');
         }
       }
       
-      // ignore: avoid_print
+      _log.i('Search complete: ${tracks.length} tracks (${extensionTracks.length} from extensions), ${artists.length} artists parsed successfully');
-      print('[Search] Parsed ${tracks.length} tracks, ${artists.length} artists');
       
       state = TrackState(
         tracks: tracks,
@@ -265,9 +412,56 @@ class TrackNotifier extends Notifier<TrackState> {
         isLoading: false,
         hasSearchText: state.hasSearchText,
       );
-    } catch (e) {
+    } catch (e, stackTrace) {
-      if (!_isRequestValid(requestId)) return; // Request cancelled
+      if (!_isRequestValid(requestId)) return;
-      // Preserve hasSearchText on error so user stays on search screen
+      _log.e('Search failed: $e', e, stackTrace);
+      state = TrackState(isLoading: false, error: e.toString(), hasSearchText: state.hasSearchText);
+    }
+  }
+
+  /// Perform custom search using a specific extension
+  Future<void> customSearch(String extensionId, String query, {Map<String, dynamic>? options}) async {
+    // Increment request ID to cancel any pending requests
+    final requestId = ++_currentRequestId;
+
+    // Preserve hasSearchText during search
+    state = TrackState(isLoading: true, hasSearchText: state.hasSearchText);
+
+    try {
+      _log.i('Custom search started: extension=$extensionId, query="$query"');
+      
+      final results = await PlatformBridge.customSearchWithExtension(extensionId, query, options: options);
+      
+      if (!_isRequestValid(requestId)) {
+        _log.w('Custom search request cancelled (requestId=$requestId)');
+        return;
+      }
+      
+      _log.i('Custom search returned ${results.length} tracks');
+      
+      // Parse tracks with error handling per item, setting source to extension ID
+      final tracks = <Track>[];
+      for (int i = 0; i < results.length; i++) {
+        final t = results[i];
+        try {
+          tracks.add(_parseSearchTrack(t, source: extensionId));
+        } catch (e) {
+          _log.e('Failed to parse custom search track[$i]: $e', e);
+        }
+      }
+      
+      _log.i('Custom search complete: ${tracks.length} tracks parsed (source=$extensionId)');
+      
+      state = TrackState(
+        tracks: tracks,
+        searchArtists: [], // Custom search doesn't return artists
+        isLoading: false,
+        hasSearchText: state.hasSearchText,
+        searchExtensionId: extensionId, // Store which extension was used
+      );
+    } catch (e, stackTrace) {
+      if (!_isRequestValid(requestId)) return;
+      _log.e('Custom search failed: $e', e, stackTrace);
       state = TrackState(isLoading: false, error: e.toString(), hasSearchText: state.hasSearchText);
     }
   }
@@ -292,6 +486,8 @@ class TrackNotifier extends Notifier<TrackState> {
         trackNumber: track.trackNumber,
         discNumber: track.discNumber,
         releaseDate: track.releaseDate,
+        albumType: track.albumType,
+        source: track.source,
         availability: ServiceAvailability(
           tidal: availability['tidal'] as bool? ?? false,
           qobuz: availability['qobuz'] as bool? ?? false,
@@ -319,6 +515,28 @@ class TrackNotifier extends Notifier<TrackState> {
     state = state.copyWith(hasSearchText: hasText);
   }
   
+  /// Set recent access mode state
+  void setShowingRecentAccess(bool showing) {
+    state = state.copyWith(isShowingRecentAccess: showing);
+  }
+  
+  /// Set tracks from a collection (album/playlist) opened from search results
+  void setTracksFromCollection({
+    required List<Track> tracks,
+    String? albumName,
+    String? playlistName,
+    String? coverUrl,
+  }) {
+    state = TrackState(
+      tracks: tracks,
+      isLoading: false,
+      albumName: albumName,
+      playlistName: playlistName,
+      coverUrl: coverUrl,
+      hasSearchText: state.hasSearchText,
+    );
+  }
+
   Track _parseTrack(Map<String, dynamic> data) {
     return Track(
       id: data['spotify_id'] as String? ?? '',
@@ -335,7 +553,7 @@ class TrackNotifier extends Notifier<TrackState> {
     );
   }
 
-  Track _parseSearchTrack(Map<String, dynamic> data) {
+  Track _parseSearchTrack(Map<String, dynamic> data, {String? source}) {
     // Handle duration_ms which might be int or double
     int durationMs = 0;
     final durationValue = data['duration_ms'];
@@ -345,18 +563,24 @@ class TrackNotifier extends Notifier<TrackState> {
       durationMs = durationValue.toInt();
     }
     
+    // Get item_type - can be 'track', 'album', or 'playlist'
+    final itemType = data['item_type']?.toString();
+    
     return Track(
       id: (data['spotify_id'] ?? data['id'] ?? '').toString(),
       name: (data['name'] ?? '').toString(),
       artistName: (data['artists'] ?? data['artist'] ?? '').toString(),
       albumName: (data['album_name'] ?? data['album'] ?? '').toString(),
       albumArtist: data['album_artist']?.toString(),
-      coverUrl: data['images']?.toString(),
+      coverUrl: (data['cover_url'] ?? data['images'])?.toString(),
       isrc: data['isrc']?.toString(),
       duration: (durationMs / 1000).round(),
       trackNumber: data['track_number'] as int?,
       discNumber: data['disc_number'] as int?,
       releaseDate: data['release_date']?.toString(),
+      source: source ?? data['source']?.toString() ?? data['provider_id']?.toString(),
+      albumType: data['album_type']?.toString(),
+      itemType: itemType,
     );
   }
 
@@ -366,9 +590,10 @@ class TrackNotifier extends Notifier<TrackState> {
       name: data['name'] as String? ?? '',
       releaseDate: data['release_date'] as String? ?? '',
       totalTracks: data['total_tracks'] as int? ?? 0,
-      coverUrl: data['images'] as String?,
+      coverUrl: (data['cover_url'] ?? data['images'])?.toString(),
       albumType: data['album_type'] as String? ?? 'album',
       artists: data['artists'] as String? ?? '',
+      providerId: data['provider_id']?.toString(),
     );
   }
 

lib/screens/album_screen.dart

@@ -2,11 +2,14 @@ import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:cached_network_image/cached_network_image.dart';
+import 'package:spotiflac_android/l10n/l10n.dart';
 import 'package:spotiflac_android/models/track.dart';
 import 'package:spotiflac_android/models/download_item.dart';
 import 'package:spotiflac_android/providers/download_queue_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
+import 'package:spotiflac_android/providers/recent_access_provider.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
+import 'package:spotiflac_android/widgets/download_service_picker.dart';
 
 /// Simple in-memory cache for album tracks
 class _AlbumCache {
@@ -61,6 +64,19 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
   @override
   void initState() {
     super.initState();
+    
+    // Record access for recent history
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      final providerId = widget.albumId.startsWith('deezer:') ? 'deezer' : 'spotify';
+      ref.read(recentAccessProvider.notifier).recordAlbumAccess(
+        id: widget.albumId,
+        name: widget.albumName,
+        artistName: widget.tracks?.firstOrNull?.artistName,
+        imageUrl: widget.coverUrl,
+        providerId: providerId,
+      );
+    });
+    
     // Priority: widget.tracks > cache > fetch
     _tracks = widget.tracks ?? _AlbumCache.get(widget.albumId);
     if (_tracks == null) {
@@ -259,7 +275,7 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
                       children: [
                         Icon(Icons.music_note, size: 14, color: colorScheme.onSecondaryContainer),
                         const SizedBox(width: 4),
-                        Text('${tracks.length} tracks', style: TextStyle(color: colorScheme.onSecondaryContainer, fontWeight: FontWeight.w600, fontSize: 12)),
+                        Text(context.l10n.tracksCount(tracks.length), style: TextStyle(color: colorScheme.onSecondaryContainer, fontWeight: FontWeight.w600, fontSize: 12)),
                       ],
                     ),
                   ),
@@ -268,7 +284,7 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
                   FilledButton.icon(
                     onPressed: () => _downloadAll(context),
                     icon: const Icon(Icons.download),
-                    label: Text('Download All (${tracks.length})'),
+                    label: Text(context.l10n.downloadAllCount(tracks.length)),
                     style: FilledButton.styleFrom(minimumSize: const Size.fromHeight(52), shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16))),
                   ),
                 ],
@@ -288,7 +304,7 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
           children: [
             Icon(Icons.queue_music, size: 20, color: colorScheme.primary),
             const SizedBox(width: 8),
-            Text('Tracks', style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w600, color: colorScheme.onSurface)),
+            Text(context.l10n.tracksHeader, style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w600, color: colorScheme.onSurface)),
           ],
         ),
       ),
@@ -316,13 +332,19 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
   void _downloadTrack(BuildContext context, Track track) {
     final settings = ref.read(settingsProvider);
     if (settings.askQualityBeforeDownload) {
-      _showQualityPicker(context, (quality, service) {
+      DownloadServicePicker.show(
-        ref.read(downloadQueueProvider.notifier).addToQueue(track, service, qualityOverride: quality);
+        context,
-        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Added "${track.name}" to queue')));
+        trackName: track.name,
-      }, trackName: track.name, artistName: track.artistName, coverUrl: track.coverUrl);
+        artistName: track.artistName,
+        coverUrl: track.coverUrl,
+        onSelect: (quality, service) {
+          ref.read(downloadQueueProvider.notifier).addToQueue(track, service, qualityOverride: quality);
+          ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAddedToQueue(track.name))));
+        },
+      );
     } else {
       ref.read(downloadQueueProvider.notifier).addToQueue(track, settings.defaultService);
-      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Added "${track.name}" to queue')));
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAddedToQueue(track.name))));
     }
   }
 
@@ -331,84 +353,21 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
     if (tracks == null || tracks.isEmpty) return;
     final settings = ref.read(settingsProvider);
     if (settings.askQualityBeforeDownload) {
-      _showQualityPicker(context, (quality, service) {
+      DownloadServicePicker.show(
-        ref.read(downloadQueueProvider.notifier).addMultipleToQueue(tracks, service, qualityOverride: quality);
+        context,
-        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Added ${tracks.length} tracks to queue')));
+        trackName: '${tracks.length} tracks',
-      }, trackName: '${tracks.length} tracks', artistName: widget.albumName);
+        artistName: widget.albumName,
+        onSelect: (quality, service) {
+          ref.read(downloadQueueProvider.notifier).addMultipleToQueue(tracks, service, qualityOverride: quality);
+          ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAddedTracksToQueue(tracks.length))));
+        },
+      );
     } else {
       ref.read(downloadQueueProvider.notifier).addMultipleToQueue(tracks, settings.defaultService);
-      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('Added ${tracks.length} tracks to queue')));
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAddedTracksToQueue(tracks.length))));
     }
   }
 
-  void _showQualityPicker(BuildContext context, void Function(String quality, String service) onSelect, {String? trackName, String? artistName, String? coverUrl}) {
-    final colorScheme = Theme.of(context).colorScheme;
-    final settings = ref.read(settingsProvider);
-    String selectedService = settings.defaultService;
-    
-    showModalBottomSheet(
-      context: context,
-      backgroundColor: colorScheme.surfaceContainerHigh,
-      shape: const RoundedRectangleBorder(borderRadius: BorderRadius.vertical(top: Radius.circular(28))),
-      isScrollControlled: true,
-      builder: (context) => StatefulBuilder(
-        builder: (context, setModalState) => SafeArea(
-          child: SingleChildScrollView(
-            child: Column(
-              mainAxisSize: MainAxisSize.min,
-              crossAxisAlignment: CrossAxisAlignment.start,
-              children: [
-                if (trackName != null) ...[
-                  _TrackInfoHeader(trackName: trackName, artistName: artistName, coverUrl: coverUrl),
-                  Divider(height: 1, color: colorScheme.outlineVariant.withValues(alpha: 0.5)),
-                ] else ...[
-                  const SizedBox(height: 8),
-                  Center(child: Container(width: 40, height: 4, decoration: BoxDecoration(color: colorScheme.onSurfaceVariant.withValues(alpha: 0.4), borderRadius: BorderRadius.circular(2)))),
-                ],
-                // Service selector
-                Padding(
-                  padding: const EdgeInsets.fromLTRB(24, 16, 24, 8),
-                  child: Text('Download From', style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold)),
-                ),
-                Padding(
-                  padding: const EdgeInsets.symmetric(horizontal: 20),
-                  child: Row(
-                    children: [
-                      _ServiceChip(label: 'Tidal', isSelected: selectedService == 'tidal', onTap: () => setModalState(() => selectedService = 'tidal')),
-                      const SizedBox(width: 8),
-                      _ServiceChip(label: 'Qobuz', isSelected: selectedService == 'qobuz', onTap: () => setModalState(() => selectedService = 'qobuz')),
-                      const SizedBox(width: 8),
-                      _ServiceChip(label: 'Amazon', isSelected: selectedService == 'amazon', onTap: () => setModalState(() => selectedService = 'amazon')),
-                    ],
-                  ),
-                ),
-                Padding(
-                  padding: const EdgeInsets.fromLTRB(24, 16, 24, 8),
-                  child: Text('Select Quality', style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold)),
-                ),
-                // Disclaimer
-                Padding(
-                  padding: const EdgeInsets.fromLTRB(24, 0, 24, 12),
-                  child: Text(
-                    'Actual quality depends on track availability. Hi-Res may not be available for all tracks.',
-                    style: Theme.of(context).textTheme.bodySmall?.copyWith(
-                      color: colorScheme.onSurfaceVariant,
-                      fontStyle: FontStyle.italic,
-                    ),
-                  ),
-                ),
-                _QualityOption(title: 'FLAC Lossless', subtitle: '16-bit / 44.1kHz', icon: Icons.music_note, onTap: () { Navigator.pop(context); onSelect('LOSSLESS', selectedService); }),
-                _QualityOption(title: 'Hi-Res FLAC', subtitle: '24-bit / up to 96kHz', icon: Icons.high_quality, onTap: () { Navigator.pop(context); onSelect('HI_RES', selectedService); }),
-                _QualityOption(title: 'Hi-Res FLAC Max', subtitle: '24-bit / up to 192kHz', icon: Icons.four_k, onTap: () { Navigator.pop(context); onSelect('HI_RES_LOSSLESS', selectedService); }),
-                const SizedBox(height: 16),
-              ],
-            ),
-          ),
-        ),
-      ),
-    );
-  }
-
   /// Build error widget with special handling for rate limit (429)
   Widget _buildErrorWidget(String error, ColorScheme colorScheme) {
     final isRateLimit = error.contains('429') || 
@@ -431,7 +390,7 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
                   crossAxisAlignment: CrossAxisAlignment.start,
                   children: [
                     Text(
-                      'Rate Limited',
+                      context.l10n.errorRateLimited,
                       style: TextStyle(
                         color: colorScheme.onErrorContainer,
                         fontWeight: FontWeight.bold,
@@ -439,7 +398,7 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
                     ),
                     const SizedBox(height: 4),
                     Text(
-                      'Too many requests. Please wait a moment and try again.',
+                      context.l10n.errorRateLimitedMessage,
                       style: TextStyle(
                         color: colorScheme.onErrorContainer,
                         fontSize: 12,
@@ -473,148 +432,6 @@ class _AlbumScreenState extends ConsumerState<AlbumScreen> {
   }
 }
 
-class _QualityOption extends StatelessWidget {
-  final String title;
-  final String subtitle;
-  final IconData icon;
-  final VoidCallback onTap;
-
-  const _QualityOption({required this.title, required this.subtitle, required this.icon, required this.onTap});
-
-  @override
-  Widget build(BuildContext context) {
-    final colorScheme = Theme.of(context).colorScheme;
-    return ListTile(
-      contentPadding: const EdgeInsets.symmetric(horizontal: 24, vertical: 4),
-      leading: Container(padding: const EdgeInsets.all(10), decoration: BoxDecoration(color: colorScheme.primaryContainer, borderRadius: BorderRadius.circular(12)), child: Icon(icon, color: colorScheme.onPrimaryContainer, size: 20)),
-      title: Text(title, style: const TextStyle(fontWeight: FontWeight.w500)),
-      subtitle: Text(subtitle, style: TextStyle(color: colorScheme.onSurfaceVariant)),
-      onTap: onTap,
-    );
-  }
-}
-
-class _ServiceChip extends StatelessWidget {
-  final String label;
-  final bool isSelected;
-  final VoidCallback onTap;
-  const _ServiceChip({required this.label, required this.isSelected, required this.onTap});
-
-  @override
-  Widget build(BuildContext context) {
-    final colorScheme = Theme.of(context).colorScheme;
-    return Expanded(
-      child: GestureDetector(
-        onTap: onTap,
-        child: AnimatedContainer(
-          duration: const Duration(milliseconds: 200),
-          padding: const EdgeInsets.symmetric(vertical: 10),
-          decoration: BoxDecoration(
-            color: isSelected ? colorScheme.primaryContainer : colorScheme.surfaceContainerHighest,
-            borderRadius: BorderRadius.circular(12),
-            border: isSelected ? null : Border.all(color: colorScheme.outlineVariant.withValues(alpha: 0.5)),
-          ),
-          child: Text(
-            label,
-            textAlign: TextAlign.center,
-            style: TextStyle(
-              fontWeight: isSelected ? FontWeight.w600 : FontWeight.normal,
-              color: isSelected ? colorScheme.onPrimaryContainer : colorScheme.onSurfaceVariant,
-            ),
-          ),
-        ),
-      ),
-    );
-  }
-}
-
-class _TrackInfoHeader extends StatefulWidget {
-  final String trackName;
-  final String? artistName;
-  final String? coverUrl;
-  const _TrackInfoHeader({required this.trackName, this.artistName, this.coverUrl});
-
-  @override
-  State<_TrackInfoHeader> createState() => _TrackInfoHeaderState();
-}
-
-class _TrackInfoHeaderState extends State<_TrackInfoHeader> {
-  bool _expanded = false;
-  bool _isOverflowing = false;
-
-  @override
-  Widget build(BuildContext context) {
-    final colorScheme = Theme.of(context).colorScheme;
-    return Material(
-      color: Colors.transparent,
-      child: InkWell(
-        onTap: _isOverflowing ? () => setState(() => _expanded = !_expanded) : null,
-        borderRadius: const BorderRadius.only(topLeft: Radius.circular(28), topRight: Radius.circular(28)),
-        child: Column(
-          children: [
-            const SizedBox(height: 8),
-            Container(width: 40, height: 4, decoration: BoxDecoration(color: colorScheme.onSurfaceVariant.withValues(alpha: 0.4), borderRadius: BorderRadius.circular(2))),
-            Padding(
-              padding: const EdgeInsets.fromLTRB(16, 12, 16, 12),
-              child: Row(
-                children: [
-                  ClipRRect(
-                    borderRadius: BorderRadius.circular(8),
-                    child: widget.coverUrl != null
-                        ? Image.network(widget.coverUrl!, width: 56, height: 56, fit: BoxFit.cover,
-                            errorBuilder: (_, e, s) => Container(width: 56, height: 56, color: colorScheme.surfaceContainerHighest, child: Icon(Icons.music_note, color: colorScheme.onSurfaceVariant)))
-                        : Container(width: 56, height: 56, color: colorScheme.surfaceContainerHighest, child: Icon(Icons.music_note, color: colorScheme.onSurfaceVariant)),
-                  ),
-                  const SizedBox(width: 12),
-                  Expanded(
-                    child: LayoutBuilder(
-                      builder: (context, constraints) {
-                        final titleStyle = Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w600);
-                        final titleSpan = TextSpan(text: widget.trackName, style: titleStyle);
-                        final titlePainter = TextPainter(text: titleSpan, maxLines: 1, textDirection: TextDirection.ltr)..layout(maxWidth: constraints.maxWidth);
-                        final titleOverflows = titlePainter.didExceedMaxLines;
-                        
-                        WidgetsBinding.instance.addPostFrameCallback((_) {
-                          if (mounted && _isOverflowing != titleOverflows) {
-                            setState(() => _isOverflowing = titleOverflows);
-                          }
-                        });
-                        
-                        return Column(
-                          crossAxisAlignment: CrossAxisAlignment.start,
-                          children: [
-                            Text(
-                              widget.trackName,
-                              style: titleStyle,
-                              maxLines: _expanded ? 10 : 1,
-                              overflow: _expanded ? TextOverflow.visible : TextOverflow.ellipsis,
-                            ),
-                            if (widget.artistName != null) ...[
-                              const SizedBox(height: 2),
-                              Text(
-                                widget.artistName!,
-                                style: Theme.of(context).textTheme.bodyMedium?.copyWith(color: colorScheme.onSurfaceVariant),
-                                maxLines: _expanded ? 3 : 1,
-                                overflow: _expanded ? TextOverflow.visible : TextOverflow.ellipsis,
-                              ),
-                            ],
-                          ],
-                        );
-                      },
-                    ),
-                  ),
-                  if (_isOverflowing || _expanded)
-                    Icon(_expanded ? Icons.expand_less : Icons.expand_more, color: colorScheme.onSurfaceVariant, size: 20),
-                ],
-              ),
-            ),
-          ],
-        ),
-      ),
-    );
-  }
-}
-
 /// Separate Consumer widget for each track - only rebuilds when this specific track's status changes
 class _AlbumTrackItem extends ConsumerWidget {
   final Track track;
@@ -674,7 +491,7 @@ class _AlbumTrackItem extends ConsumerWidget {
         final fileExists = await File(historyItem.filePath).exists();
         if (fileExists) {
           if (context.mounted) {
-            ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('"${track.name}" already downloaded')));
+            ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(context.l10n.snackbarAlreadyDownloaded(track.name))));
           }
           return;
         } else {

lib/screens/artist_screen.dart

@@ -1,50 +1,87 @@
+import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:cached_network_image/cached_network_image.dart';
+import 'package:intl/intl.dart';
+import 'package:spotiflac_android/l10n/l10n.dart';
+import 'package:spotiflac_android/models/track.dart';
+import 'package:spotiflac_android/models/download_item.dart';
 import 'package:spotiflac_android/providers/track_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
+import 'package:spotiflac_android/providers/download_queue_provider.dart';
+import 'package:spotiflac_android/providers/recent_access_provider.dart';
 import 'package:spotiflac_android/services/platform_bridge.dart';
 import 'package:spotiflac_android/screens/album_screen.dart';
+import 'package:spotiflac_android/screens/home_tab.dart' show ExtensionAlbumScreen;
 
-/// Simple in-memory cache for artist discography
+/// Simple in-memory cache for artist data
 class _ArtistCache {
   static final Map<String, _CacheEntry> _cache = {};
   static const Duration _ttl = Duration(minutes: 10);
 
-  static List<ArtistAlbum>? get(String artistId) {
+  static _CacheEntry? get(String artistId) {
     final entry = _cache[artistId];
     if (entry == null) return null;
     if (DateTime.now().isAfter(entry.expiresAt)) {
       _cache.remove(artistId);
       return null;
     }
-    return entry.albums;
+    return entry;
   }
 
-  static void set(String artistId, List<ArtistAlbum> albums) {
+  static void set(String artistId, {
-    _cache[artistId] = _CacheEntry(albums, DateTime.now().add(_ttl));
+    required List<ArtistAlbum> albums,
+    List<Track>? topTracks,
+    String? headerImageUrl,
+    int? monthlyListeners,
+  }) {
+    _cache[artistId] = _CacheEntry(
+      albums: albums,
+      topTracks: topTracks,
+      headerImageUrl: headerImageUrl,
+      monthlyListeners: monthlyListeners,
+      expiresAt: DateTime.now().add(_ttl),
+    );
   }
 }
 
 class _CacheEntry {
   final List<ArtistAlbum> albums;
+  final List<Track>? topTracks;
+  final String? headerImageUrl;
+  final int? monthlyListeners;
   final DateTime expiresAt;
-  _CacheEntry(this.albums, this.expiresAt);
+  
+  _CacheEntry({
+    required this.albums,
+    this.topTracks,
+    this.headerImageUrl,
+    this.monthlyListeners,
+    required this.expiresAt,
+  });
 }
 
-/// Artist screen with Material Expressive 3 design - shows discography
+/// Artist screen with Spotify-like design
 class ArtistScreen extends ConsumerStatefulWidget {
   final String artistId;
   final String artistName;
   final String? coverUrl;
-  final List<ArtistAlbum>? albums; // Optional - will fetch if null
+  final String? headerImageUrl;
+  final int? monthlyListeners;
+  final List<ArtistAlbum>? albums;
+  final List<Track>? topTracks;
+  final String? extensionId; // If set, skip fetching from Spotify/Deezer
 
   const ArtistScreen({
     super.key,
     required this.artistId,
     required this.artistName,
     this.coverUrl,
+    this.headerImageUrl,
+    this.monthlyListeners,
     this.albums,
+    this.topTracks,
+    this.extensionId,
   });
 
   @override
@@ -54,14 +91,62 @@ class ArtistScreen extends ConsumerStatefulWidget {
 class _ArtistScreenState extends ConsumerState<ArtistScreen> {
   bool _isLoadingDiscography = false;
   List<ArtistAlbum>? _albums;
+  List<Track>? _topTracks;
+  String? _headerImageUrl;
+  int? _monthlyListeners;
   String? _error;
 
   @override
   void initState() {
     super.initState();
-    // Priority: widget.albums > cache > fetch
+    
-    _albums = widget.albums ?? _ArtistCache.get(widget.artistId);
+    // Record access for recent history
-    if (_albums == null) {
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      final providerId = widget.extensionId ?? 
+                        (widget.artistId.startsWith('deezer:') ? 'deezer' : 'spotify');
+      ref.read(recentAccessProvider.notifier).recordArtistAccess(
+        id: widget.artistId,
+        name: widget.artistName,
+        imageUrl: widget.coverUrl,
+        providerId: providerId,
+      );
+    });
+    
+    // If this is an extension artist, use provided data only - don't fetch from Spotify/Deezer
+    if (widget.extensionId != null) {
+      _albums = widget.albums;
+      _topTracks = widget.topTracks;
+      _headerImageUrl = widget.headerImageUrl;
+      _monthlyListeners = widget.monthlyListeners;
+      // Extension artists don't need additional fetching
+      return;
+    }
+    
+    // Priority: widget data > cache > fetch
+    // But always fetch if topTracks is missing (to get popular tracks)
+    final cached = _ArtistCache.get(widget.artistId);
+    
+    if (widget.albums != null) {
+      _albums = widget.albums;
+      _topTracks = widget.topTracks;
+      _headerImageUrl = widget.headerImageUrl;
+      _monthlyListeners = widget.monthlyListeners;
+      
+      // If we have albums but no top tracks, fetch to get them
+      if (_topTracks == null || _topTracks!.isEmpty) {
+        _fetchDiscography();
+      }
+    } else if (cached != null) {
+      _albums = cached.albums;
+      _topTracks = cached.topTracks;
+      _headerImageUrl = cached.headerImageUrl;
+      _monthlyListeners = cached.monthlyListeners;
+      
+      // If cache has no top tracks, fetch
+      if (_topTracks == null || _topTracks!.isEmpty) {
+        _fetchDiscography();
+      }
+    } else {
       _fetchDiscography();
     }
   }
@@ -70,31 +155,60 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
     setState(() => _isLoadingDiscography = true);
     try {
       List<ArtistAlbum> albums;
+      List<Track>? topTracks;
+      String? headerImage;
+      int? listeners;
       
       // Check if this is a Deezer artist ID (format: "deezer:123456")
       if (widget.artistId.startsWith('deezer:')) {
         final deezerArtistId = widget.artistId.replaceFirst('deezer:', '');
-        // ignore: avoid_print
-        print('[ArtistScreen] Fetching from Deezer: $deezerArtistId');
         final metadata = await PlatformBridge.getDeezerMetadata('artist', deezerArtistId);
         final albumsList = metadata['albums'] as List<dynamic>;
         albums = albumsList.map((a) => _parseArtistAlbum(a as Map<String, dynamic>)).toList();
       } else {
-        // Spotify artist - use fallback method
+        // Spotify artist - use extension handler via URL
-        // ignore: avoid_print
-        print('[ArtistScreen] Fetching from Spotify with fallback: ${widget.artistId}');
         final url = 'https://open.spotify.com/artist/${widget.artistId}';
-        final metadata = await PlatformBridge.getSpotifyMetadataWithFallback(url);
+        final result = await PlatformBridge.handleURLWithExtension(url);
-        final albumsList = metadata['albums'] as List<dynamic>;
+        
-        albums = albumsList.map((a) => _parseArtistAlbum(a as Map<String, dynamic>)).toList();
+        if (result != null && result['artist'] != null) {
+          final artistData = result['artist'] as Map<String, dynamic>;
+          final albumsList = artistData['albums'] as List<dynamic>? ?? [];
+          albums = albumsList.map((a) => _parseArtistAlbum(a as Map<String, dynamic>)).toList();
+          
+          // Parse top tracks if available
+          final topTracksList = artistData['top_tracks'] as List<dynamic>? ?? [];
+          if (topTracksList.isNotEmpty) {
+            topTracks = topTracksList.map((t) => _parseTrack(t as Map<String, dynamic>)).toList();
+          }
+          
+          headerImage = artistData['header_image'] as String?;
+          listeners = artistData['listeners'] as int?;
+        } else {
+          // Fallback to Spotify API metadata
+          final metadata = await PlatformBridge.getSpotifyMetadataWithFallback(url);
+          final albumsList = metadata['albums'] as List<dynamic>;
+          albums = albumsList.map((a) => _parseArtistAlbum(a as Map<String, dynamic>)).toList();
+        }
       }
       
-      // Store in cache
+      // Store in cache (preserve existing values if new ones are null)
-      _ArtistCache.set(widget.artistId, albums);
+      final finalHeaderImage = headerImage ?? _headerImageUrl ?? widget.headerImageUrl;
+      final finalListeners = listeners ?? _monthlyListeners ?? widget.monthlyListeners;
+      
+      _ArtistCache.set(
+        widget.artistId,
+        albums: albums,
+        topTracks: topTracks,
+        headerImageUrl: finalHeaderImage,
+        monthlyListeners: finalListeners,
+      );
       
       if (mounted) {
         setState(() {
           _albums = albums;
+          _topTracks = topTracks;
+          _headerImageUrl = finalHeaderImage;
+          _monthlyListeners = finalListeners;
           _isLoadingDiscography = false;
         });
       }
@@ -108,15 +222,41 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
     }
   }
 
+  Track _parseTrack(Map<String, dynamic> data) {
+    int durationMs = 0;
+    final durationValue = data['duration_ms'];
+    if (durationValue is int) {
+      durationMs = durationValue;
+    } else if (durationValue is double) {
+      durationMs = durationValue.toInt();
+    }
+    
+    return Track(
+      id: (data['spotify_id'] ?? data['id'] ?? '').toString(),
+      name: (data['name'] ?? '').toString(),
+      artistName: (data['artists'] ?? data['artist'] ?? '').toString(),
+      albumName: (data['album_name'] ?? data['album'] ?? '').toString(),
+      albumArtist: data['album_artist']?.toString(),
+      coverUrl: (data['cover_url'] ?? data['images'])?.toString(),
+      isrc: data['isrc']?.toString(),
+      duration: (durationMs / 1000).round(),
+      trackNumber: data['track_number'] as int?,
+      discNumber: data['disc_number'] as int?,
+      releaseDate: data['release_date']?.toString(),
+      source: data['provider_id']?.toString(),
+    );
+  }
+
   ArtistAlbum _parseArtistAlbum(Map<String, dynamic> data) {
     return ArtistAlbum(
       id: data['id'] as String? ?? '',
       name: data['name'] as String? ?? '',
       releaseDate: data['release_date'] as String? ?? '',
       totalTracks: data['total_tracks'] as int? ?? 0,
-      coverUrl: data['images'] as String?,
+      coverUrl: (data['cover_url'] ?? data['images'])?.toString(),
       albumType: data['album_type'] as String? ?? 'album',
       artists: data['artists'] as String? ?? '',
+      providerId: data['provider_id']?.toString(),
     );
   }
 
@@ -129,43 +269,63 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
     final compilations = albums.where((a) => a.albumType == 'compilation').toList();
 
     return Scaffold(
-      body: Stack(
+      body: CustomScrollView(
-        children: [
+        slivers: [
-          CustomScrollView(
+          _buildHeader(context, colorScheme),
-            slivers: [
+          if (_isLoadingDiscography)
-              _buildAppBar(context, colorScheme),
+            const SliverToBoxAdapter(child: Padding(
-              _buildInfoCard(context, colorScheme),
+              padding: EdgeInsets.all(32),
-              if (_isLoadingDiscography)
+              child: Center(child: CircularProgressIndicator()),
-                const SliverToBoxAdapter(child: Padding(
+            )),
-                  padding: EdgeInsets.all(32),
+          if (_error != null)
-                  child: Center(child: CircularProgressIndicator()),
+            SliverToBoxAdapter(child: Padding(
-                )),
+              padding: const EdgeInsets.all(16),
-              if (_error != null)
+              child: _buildErrorWidget(_error!, colorScheme),
-                SliverToBoxAdapter(child: Padding(
+            )),
-                  padding: const EdgeInsets.all(16),
+          if (!_isLoadingDiscography && _error == null) ...[
-                  child: _buildErrorWidget(_error!, colorScheme),
+            // Popular tracks section
-                )),
+            if (_topTracks != null && _topTracks!.isNotEmpty)
-              if (!_isLoadingDiscography && _error == null) ...[
+              SliverToBoxAdapter(child: _buildPopularSection(colorScheme)),
-                if (albumsOnly.isNotEmpty) SliverToBoxAdapter(child: _buildAlbumSection('Albums', albumsOnly, colorScheme)),
+            // Discography sections
-                if (singles.isNotEmpty) SliverToBoxAdapter(child: _buildAlbumSection('Singles & EPs', singles, colorScheme)),
+            if (albumsOnly.isNotEmpty) 
-                if (compilations.isNotEmpty) SliverToBoxAdapter(child: _buildAlbumSection('Compilations', compilations, colorScheme)),
+              SliverToBoxAdapter(child: _buildAlbumSection(context.l10n.artistAlbums, albumsOnly, colorScheme)),
-              ],
+            if (singles.isNotEmpty) 
-              const SliverToBoxAdapter(child: SizedBox(height: 32)),
+              SliverToBoxAdapter(child: _buildAlbumSection(context.l10n.artistSingles, singles, colorScheme)),
-            ],
+            if (compilations.isNotEmpty) 
-          ),
+              SliverToBoxAdapter(child: _buildAlbumSection(context.l10n.artistCompilations, compilations, colorScheme)),
+          ],
+          const SliverToBoxAdapter(child: SizedBox(height: 32)),
         ],
       ),
     );
   }
 
-  Widget _buildAppBar(BuildContext context, ColorScheme colorScheme) {
+  /// Build Spotify-style header with full-width image and artist name overlay
-    // Validate image URL - must be non-null, non-empty, and have a valid host
+  Widget _buildHeader(BuildContext context, ColorScheme colorScheme) {
-    final hasValidImage = widget.coverUrl != null && 
+    // Use header image if available, otherwise fall back to cover URL
-                          widget.coverUrl!.isNotEmpty &&
+    // Prefer: fetched header > widget header > widget cover
-                          Uri.tryParse(widget.coverUrl!)?.hasAuthority == true;
+    String? imageUrl = _headerImageUrl;
+    if (imageUrl == null || imageUrl.isEmpty) {
+      imageUrl = widget.headerImageUrl;
+    }
+    if (imageUrl == null || imageUrl.isEmpty) {
+      imageUrl = widget.coverUrl;
+    }
+    
+    final hasValidImage = imageUrl != null && 
+                          imageUrl.isNotEmpty &&
+                          Uri.tryParse(imageUrl)?.hasAuthority == true;
+    
+    // Format monthly listeners
+    String? listenersText;
+    final listeners = _monthlyListeners ?? widget.monthlyListeners;
+    if (listeners != null && listeners > 0) {
+      final formatter = NumberFormat.compact();
+      listenersText = context.l10n.artistMonthlyListeners(formatter.format(listeners));
+    }
     
     return SliverAppBar(
-      expandedHeight: 280,
+      expandedHeight: 380,
       pinned: true,
       stretch: true,
       backgroundColor: colorScheme.surface,
@@ -174,49 +334,84 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
         background: Stack(
           fit: StackFit.expand,
           children: [
+            // Background image - full width, no circular crop
             if (hasValidImage)
               CachedNetworkImage(
-                imageUrl: widget.coverUrl!, 
+                imageUrl: imageUrl,
                 fit: BoxFit.cover,
-                color: Colors.black.withValues(alpha: 0.5), 
+                alignment: Alignment.topCenter, // Show top of image (faces)
-                colorBlendMode: BlendMode.darken, 
+                memCacheWidth: 800,
-                memCacheWidth: 600,
+                placeholder: (context, url) => Container(
-                errorWidget: (context, url, error) => Container(color: colorScheme.surfaceContainerHighest),
+                  color: colorScheme.surfaceContainerHighest,
+                ),
+                errorWidget: (context, url, error) => Container(
+                  color: colorScheme.surfaceContainerHighest,
+                  child: Icon(Icons.person, size: 80, color: colorScheme.onSurfaceVariant),
+                ),
+              )
+            else
+              Container(
+                color: colorScheme.surfaceContainerHighest,
+                child: Icon(Icons.person, size: 80, color: colorScheme.onSurfaceVariant),
               ),
+            // Gradient overlay for text readability
             Container(
               decoration: BoxDecoration(
                 gradient: LinearGradient(
                   begin: Alignment.topCenter,
                   end: Alignment.bottomCenter,
-                  colors: [Colors.transparent, colorScheme.surface.withValues(alpha: 0.8), colorScheme.surface],
+                  colors: [
-                  stops: const [0.0, 0.7, 1.0],
+                    Colors.transparent,
+                    Colors.black.withValues(alpha: 0.3),
+                    Colors.black.withValues(alpha: 0.7),
+                    colorScheme.surface,
+                  ],
+                  stops: const [0.0, 0.5, 0.75, 1.0],
                 ),
               ),
             ),
-            Center(
+            // Artist name and listeners at bottom
-              child: Padding(
+            Positioned(
-                padding: const EdgeInsets.only(top: 60),
+              left: 16,
-                child: Container(
+              right: 16,
-                  width: 140,
+              bottom: 16,
-                  height: 140,
+              child: Column(
-                  decoration: BoxDecoration(
+                crossAxisAlignment: CrossAxisAlignment.start,
-                    shape: BoxShape.circle,
+                mainAxisSize: MainAxisSize.min,
-                    boxShadow: [BoxShadow(color: Colors.black.withValues(alpha: 0.3), blurRadius: 20, offset: const Offset(0, 10))],
+                children: [
+                  Text(
+                    widget.artistName,
+                    style: Theme.of(context).textTheme.headlineLarge?.copyWith(
+                      fontWeight: FontWeight.bold,
+                      color: Colors.white,
+                      shadows: [
+                        Shadow(
+                          offset: const Offset(0, 1),
+                          blurRadius: 4,
+                          color: Colors.black.withValues(alpha: 0.5),
+                        ),
+                      ],
+                    ),
+                    maxLines: 2,
+                    overflow: TextOverflow.ellipsis,
                   ),
-                  child: ClipOval(
+                  if (listenersText != null) ...[
-                    child: hasValidImage
+                    const SizedBox(height: 4),
-                        ? CachedNetworkImage(
+                    Text(
-                            imageUrl: widget.coverUrl!, 
+                      listenersText,
-                            fit: BoxFit.cover, 
+                      style: Theme.of(context).textTheme.bodyMedium?.copyWith(
-                            memCacheWidth: 280,
+                        color: Colors.white.withValues(alpha: 0.8),
-                            errorWidget: (context, url, error) => Container(
+                        shadows: [
-                              color: colorScheme.surfaceContainerHighest, 
+                          Shadow(
-                              child: Icon(Icons.person, size: 48, color: colorScheme.onSurfaceVariant),
+                            offset: const Offset(0, 1),
-                            ),
+                            blurRadius: 2,
-                          )
+                            color: Colors.black.withValues(alpha: 0.5),
-                        : Container(color: colorScheme.surfaceContainerHighest, child: Icon(Icons.person, size: 48, color: colorScheme.onSurfaceVariant)),
+                          ),
-                  ),
+                        ],
-                ),
+                      ),
+                    ),
+                  ],
+                ],
               ),
             ),
           ],
@@ -224,44 +419,280 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
         stretchModes: const [StretchMode.zoomBackground, StretchMode.blurBackground],
       ),
       leading: IconButton(
-        icon: Container(padding: const EdgeInsets.all(8), decoration: BoxDecoration(color: colorScheme.surface.withValues(alpha: 0.8), shape: BoxShape.circle), child: Icon(Icons.arrow_back, color: colorScheme.onSurface)),
+        icon: Container(
+          padding: const EdgeInsets.all(8),
+          decoration: BoxDecoration(
+            color: Colors.black.withValues(alpha: 0.4),
+            shape: BoxShape.circle,
+          ),
+          child: const Icon(Icons.arrow_back, color: Colors.white),
+        ),
         onPressed: () => Navigator.pop(context),
       ),
     );
   }
 
-  Widget _buildInfoCard(BuildContext context, ColorScheme colorScheme) {
+  /// Build Popular tracks section like Spotify
-    return SliverToBoxAdapter(
+  Widget _buildPopularSection(ColorScheme colorScheme) {
-      child: Padding(
+    if (_topTracks == null || _topTracks!.isEmpty) return const SizedBox.shrink();
-        padding: const EdgeInsets.all(16),
+    
-        child: Card(
+    // Show max 5 tracks
-          elevation: 0,
+    final tracks = _topTracks!.take(5).toList();
-          color: colorScheme.surfaceContainerLow,
+    
-          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
+    return Column(
-          child: Padding(
+      crossAxisAlignment: CrossAxisAlignment.start,
-            padding: const EdgeInsets.all(20),
+      children: [
-            child: Column(
+        Padding(
-              crossAxisAlignment: CrossAxisAlignment.start,
+          padding: const EdgeInsets.fromLTRB(16, 24, 16, 12),
-              children: [
+          child: Text(
-                Text(widget.artistName, style: Theme.of(context).textTheme.headlineSmall?.copyWith(fontWeight: FontWeight.bold, color: colorScheme.onSurface)),
+            context.l10n.artistPopular,
-                const SizedBox(height: 8),
+            style: Theme.of(context).textTheme.titleLarge?.copyWith(
-                if (_albums != null)
+              fontWeight: FontWeight.bold,
-                  Container(
-                    padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
-                    decoration: BoxDecoration(color: colorScheme.primaryContainer, borderRadius: BorderRadius.circular(20)),
-                    child: Row(
-                      mainAxisSize: MainAxisSize.min,
-                      children: [
-                        Icon(Icons.album, size: 14, color: colorScheme.onPrimaryContainer),
-                        const SizedBox(width: 4),
-                        Text('${_albums!.length} releases', style: TextStyle(color: colorScheme.onPrimaryContainer, fontWeight: FontWeight.w600, fontSize: 12)),
-                      ],
-                    ),
-                  ),
-              ],
             ),
           ),
         ),
+        ...tracks.asMap().entries.map((entry) {
+          final index = entry.key;
+          final track = entry.value;
+          return _buildPopularTrackItem(index + 1, track, colorScheme);
+        }),
+      ],
+    );
+  }
+
+  /// Build a single popular track item with dynamic download status
+  Widget _buildPopularTrackItem(int rank, Track track, ColorScheme colorScheme) {
+    // Watch download queue for this track's status
+    final queueItem = ref.watch(downloadQueueProvider.select((state) {
+      return state.items.where((item) => item.track.id == track.id).firstOrNull;
+    }));
+    
+    // Check if track is in history (already downloaded before)
+    final isInHistory = ref.watch(downloadHistoryProvider.select((state) {
+      return state.isDownloaded(track.id);
+    }));
+    
+    final isQueued = queueItem != null;
+    final isDownloading = queueItem?.status == DownloadStatus.downloading;
+    final isFinalizing = queueItem?.status == DownloadStatus.finalizing;
+    final isCompleted = queueItem?.status == DownloadStatus.completed;
+    final progress = queueItem?.progress ?? 0.0;
+    
+    // Show as downloaded if in queue completed OR in history
+    final showAsDownloaded = isCompleted || (!isQueued && isInHistory);
+    
+    return InkWell(
+      onTap: () => _handlePopularTrackTap(track, isQueued: isQueued, isInHistory: isInHistory),
+      child: Padding(
+        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
+        child: Row(
+          children: [
+            // Rank number
+            SizedBox(
+              width: 24,
+              child: Text(
+                '$rank',
+                style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                  color: colorScheme.onSurfaceVariant,
+                ),
+                textAlign: TextAlign.center,
+              ),
+            ),
+            const SizedBox(width: 12),
+            // Album art
+            ClipRRect(
+              borderRadius: BorderRadius.circular(4),
+              child: track.coverUrl != null
+                  ? CachedNetworkImage(
+                      imageUrl: track.coverUrl!,
+                      width: 48,
+                      height: 48,
+                      fit: BoxFit.cover,
+                      memCacheWidth: 96,
+                      placeholder: (context, url) => Container(
+                        width: 48,
+                        height: 48,
+                        color: colorScheme.surfaceContainerHighest,
+                      ),
+                      errorWidget: (context, url, error) => Container(
+                        width: 48,
+                        height: 48,
+                        color: colorScheme.surfaceContainerHighest,
+                        child: Icon(Icons.music_note, color: colorScheme.onSurfaceVariant, size: 24),
+                      ),
+                    )
+                  : Container(
+                      width: 48,
+                      height: 48,
+                      color: colorScheme.surfaceContainerHighest,
+                      child: Icon(Icons.music_note, color: colorScheme.onSurfaceVariant, size: 24),
+                    ),
+            ),
+            const SizedBox(width: 12),
+            // Track info
+            Expanded(
+              child: Column(
+                crossAxisAlignment: CrossAxisAlignment.start,
+                children: [
+                  Text(
+                    track.name,
+                    style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                      fontWeight: FontWeight.w500,
+                    ),
+                    maxLines: 1,
+                    overflow: TextOverflow.ellipsis,
+                  ),
+                  if (track.albumName.isNotEmpty)
+                    Text(
+                      track.albumName,
+                      style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                        color: colorScheme.onSurfaceVariant,
+                      ),
+                      maxLines: 1,
+                      overflow: TextOverflow.ellipsis,
+                    ),
+                ],
+              ),
+            ),
+            // Download button with status
+            _buildPopularDownloadButton(
+              track: track,
+              colorScheme: colorScheme,
+              isQueued: isQueued,
+              isDownloading: isDownloading,
+              isFinalizing: isFinalizing,
+              showAsDownloaded: showAsDownloaded,
+              isInHistory: isInHistory,
+              progress: progress,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  /// Handle tap on popular track item
+  void _handlePopularTrackTap(Track track, {required bool isQueued, required bool isInHistory}) async {
+    if (isQueued) return;
+    
+    if (isInHistory) {
+      final historyItem = ref.read(downloadHistoryProvider.notifier).getBySpotifyId(track.id);
+      if (historyItem != null) {
+        final fileExists = await File(historyItem.filePath).exists();
+        if (fileExists) {
+          if (mounted) {
+            ScaffoldMessenger.of(context).showSnackBar(
+              SnackBar(content: Text(context.l10n.snackbarAlreadyDownloaded(track.name))),
+            );
+          }
+          return;
+        } else {
+          ref.read(downloadHistoryProvider.notifier).removeBySpotifyId(track.id);
+        }
+      }
+    }
+    
+    _downloadTrack(track);
+  }
+
+  /// Build download button with status indicator for popular tracks
+  Widget _buildPopularDownloadButton({
+    required Track track,
+    required ColorScheme colorScheme,
+    required bool isQueued,
+    required bool isDownloading,
+    required bool isFinalizing,
+    required bool showAsDownloaded,
+    required bool isInHistory,
+    required double progress,
+  }) {
+    const double size = 40.0;
+    const double iconSize = 20.0;
+    
+    if (showAsDownloaded) {
+      return GestureDetector(
+        onTap: () => _handlePopularTrackTap(track, isQueued: isQueued, isInHistory: isInHistory),
+        child: Container(
+          width: size,
+          height: size,
+          decoration: BoxDecoration(
+            color: colorScheme.primaryContainer,
+            shape: BoxShape.circle,
+          ),
+          child: Icon(Icons.check, color: colorScheme.onPrimaryContainer, size: iconSize),
+        ),
+      );
+    } else if (isFinalizing) {
+      return SizedBox(
+        width: size,
+        height: size,
+        child: Stack(
+          alignment: Alignment.center,
+          children: [
+            CircularProgressIndicator(
+              strokeWidth: 2.5,
+              color: colorScheme.tertiary,
+              backgroundColor: colorScheme.surfaceContainerHighest,
+            ),
+            Icon(Icons.edit_note, color: colorScheme.tertiary, size: 14),
+          ],
+        ),
+      );
+    } else if (isDownloading) {
+      return SizedBox(
+        width: size,
+        height: size,
+        child: Stack(
+          alignment: Alignment.center,
+          children: [
+            CircularProgressIndicator(
+              value: progress > 0 ? progress : null,
+              strokeWidth: 2.5,
+              color: colorScheme.primary,
+              backgroundColor: colorScheme.surfaceContainerHighest,
+            ),
+            if (progress > 0)
+              Text(
+                '${(progress * 100).toInt()}',
+                style: TextStyle(fontSize: 9, fontWeight: FontWeight.bold, color: colorScheme.primary),
+              ),
+          ],
+        ),
+      );
+    } else if (isQueued) {
+      return Container(
+        width: size,
+        height: size,
+        decoration: BoxDecoration(
+          color: colorScheme.surfaceContainerHighest,
+          shape: BoxShape.circle,
+        ),
+        child: Icon(Icons.hourglass_empty, color: colorScheme.onSurfaceVariant, size: iconSize),
+      );
+    } else {
+      return GestureDetector(
+        onTap: () => _downloadTrack(track),
+        child: Container(
+          width: size,
+          height: size,
+          decoration: BoxDecoration(
+            color: colorScheme.secondaryContainer,
+            shape: BoxShape.circle,
+          ),
+          child: Icon(Icons.download, color: colorScheme.onSecondaryContainer, size: iconSize),
+        ),
+      );
+    }
+  }
+
+  void _downloadTrack(Track track) {
+    final settings = ref.read(settingsProvider);
+    ref.read(settingsProvider.notifier).setHasSearchedBefore();
+    ref.read(downloadQueueProvider.notifier).addToQueue(track, settings.defaultService);
+    ScaffoldMessenger.of(context).showSnackBar(
+      SnackBar(
+        content: Text(context.l10n.snackbarAddedToQueue(track.name)),
+        duration: const Duration(seconds: 2),
       ),
     );
   }
@@ -271,24 +702,26 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
       crossAxisAlignment: CrossAxisAlignment.start,
       children: [
         Padding(
-          padding: const EdgeInsets.fromLTRB(20, 16, 20, 8),
+          padding: const EdgeInsets.fromLTRB(16, 24, 16, 12),
-          child: Row(
+          child: Text(
-            children: [
+            '$title (${albums.length})',
-              Icon(Icons.album, size: 20, color: colorScheme.primary),
+            style: Theme.of(context).textTheme.titleLarge?.copyWith(
-              const SizedBox(width: 8),
+              fontWeight: FontWeight.bold,
-              Text('$title (${albums.length})', style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w600, color: colorScheme.primary)),
+            ),
-            ],
           ),
         ),
         SizedBox(
-          height: 210,
+          height: 220,
           child: ListView.builder(
             scrollDirection: Axis.horizontal,
             padding: const EdgeInsets.symmetric(horizontal: 12),
             itemCount: albums.length,
             itemBuilder: (context, index) {
               final album = albums[index];
-              return KeyedSubtree(key: ValueKey(album.id), child: _buildAlbumCard(album, colorScheme));
+              return KeyedSubtree(
+                key: ValueKey(album.id),
+                child: _buildAlbumCard(album, colorScheme),
+              );
             },
           ),
         ),
@@ -301,62 +734,90 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
       onTap: () => _navigateToAlbum(album),
       child: Container(
         width: 140,
-        margin: const EdgeInsets.symmetric(horizontal: 6),
+        margin: const EdgeInsets.symmetric(horizontal: 4),
-        child: Card(
+        child: Column(
-          elevation: 0,
+          crossAxisAlignment: CrossAxisAlignment.start,
-          color: colorScheme.surfaceContainerLow,
+          children: [
-          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
+            // Album cover
-          child: Padding(
+            ClipRRect(
-            padding: const EdgeInsets.all(8),
+              borderRadius: BorderRadius.circular(8),
-            child: Column(
+              child: album.coverUrl != null
-              crossAxisAlignment: CrossAxisAlignment.start,
+                  ? CachedNetworkImage(
-              children: [
+                      imageUrl: album.coverUrl!,
-                ClipRRect(
+                      width: 140,
-                  borderRadius: BorderRadius.circular(12),
+                      height: 140,
-                  child: album.coverUrl != null
+                      fit: BoxFit.cover,
-                      ? CachedNetworkImage(imageUrl: album.coverUrl!, width: 124, height: 124, fit: BoxFit.cover, memCacheWidth: 248)
+                      memCacheWidth: 280,
-                      : Container(width: 124, height: 124, color: colorScheme.surfaceContainerHighest, child: Icon(Icons.album, color: colorScheme.onSurfaceVariant, size: 40)),
+                      placeholder: (context, url) => Container(
-                ),
+                        width: 140,
-                const SizedBox(height: 6),
+                        height: 140,
-                Expanded(
+                        color: colorScheme.surfaceContainerHighest,
-                  child: Column(
-                    crossAxisAlignment: CrossAxisAlignment.start,
-                    children: [
-                      Text(album.name, style: Theme.of(context).textTheme.bodySmall?.copyWith(fontWeight: FontWeight.w600), maxLines: 2, overflow: TextOverflow.ellipsis),
-                      const Spacer(),
-                      Text(
-                        album.totalTracks > 0 
-                            ? '${album.releaseDate.length >= 4 ? album.releaseDate.substring(0, 4) : album.releaseDate} • ${album.totalTracks} tracks'
-                            : album.releaseDate.length >= 4 ? album.releaseDate.substring(0, 4) : album.releaseDate,
-                        style: Theme.of(context).textTheme.bodySmall?.copyWith(color: colorScheme.onSurfaceVariant, fontSize: 11),
-                        maxLines: 1,
-                        overflow: TextOverflow.ellipsis,
                       ),
-                    ],
+                      errorWidget: (context, url, error) => Container(
-                  ),
+                        width: 140,
-                ),
+                        height: 140,
-              ],
+                        color: colorScheme.surfaceContainerHighest,
+                        child: Icon(Icons.album, color: colorScheme.onSurfaceVariant, size: 40),
+                      ),
+                    )
+                  : Container(
+                      width: 140,
+                      height: 140,
+                      color: colorScheme.surfaceContainerHighest,
+                      child: Icon(Icons.album, color: colorScheme.onSurfaceVariant, size: 40),
+                    ),
             ),
-          ),
+            const SizedBox(height: 8),
+            // Album name
+            Text(
+              album.name,
+              style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                fontWeight: FontWeight.w500,
+              ),
+              maxLines: 2,
+              overflow: TextOverflow.ellipsis,
+            ),
+            const SizedBox(height: 2),
+            // Year and track count
+            Text(
+              album.totalTracks > 0 
+                  ? '${album.releaseDate.length >= 4 ? album.releaseDate.substring(0, 4) : album.releaseDate} ${context.l10n.tracksCount(album.totalTracks)}'
+                  : album.releaseDate.length >= 4 ? album.releaseDate.substring(0, 4) : album.releaseDate,
+              style: Theme.of(context).textTheme.bodySmall?.copyWith(
+                color: colorScheme.onSurfaceVariant,
+              ),
+              maxLines: 1,
+              overflow: TextOverflow.ellipsis,
+            ),
+          ],
         ),
       ),
     );
   }
 
   void _navigateToAlbum(ArtistAlbum album) {
-    // Navigate immediately with data from artist discography, fetch tracks in AlbumScreen
     ref.read(settingsProvider.notifier).setHasSearchedBefore();
-    Navigator.push(context, MaterialPageRoute(
+    
-      builder: (context) => AlbumScreen(
+    if (album.providerId != null && album.providerId!.isNotEmpty) {
-        albumId: album.id,
+      Navigator.push(context, MaterialPageRoute(
-        albumName: album.name,
+        builder: (context) => ExtensionAlbumScreen(
-        coverUrl: album.coverUrl,
+          extensionId: album.providerId!,
-        // tracks: null - will be fetched in AlbumScreen
+          albumId: album.id,
-      ),
+          albumName: album.name,
-    ));
+          coverUrl: album.coverUrl,
+        ),
+      ));
+    } else {
+      Navigator.push(context, MaterialPageRoute(
+        builder: (context) => AlbumScreen(
+          albumId: album.id,
+          albumName: album.name,
+          coverUrl: album.coverUrl,
+        ),
+      ));
+    }
   }
 
-  /// Build error widget with special handling for rate limit (429)
   Widget _buildErrorWidget(String error, ColorScheme colorScheme) {
     final isRateLimit = error.contains('429') || 
                         error.toLowerCase().contains('rate limit') ||
@@ -366,7 +827,7 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
       return Card(
         elevation: 0,
         color: colorScheme.errorContainer,
-        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
+        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
         child: Padding(
           padding: const EdgeInsets.all(16),
           child: Row(
@@ -378,7 +839,7 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
                   crossAxisAlignment: CrossAxisAlignment.start,
                   children: [
                     Text(
-                      'Rate Limited',
+                      context.l10n.errorRateLimited,
                       style: TextStyle(
                         color: colorScheme.onErrorContainer,
                         fontWeight: FontWeight.bold,
@@ -386,7 +847,7 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
                     ),
                     const SizedBox(height: 4),
                     Text(
-                      'Too many requests. Please wait a moment and try again.',
+                      context.l10n.errorRateLimitedMessage,
                       style: TextStyle(
                         color: colorScheme.onErrorContainer,
                         fontSize: 12,
@@ -401,11 +862,10 @@ class _ArtistScreenState extends ConsumerState<ArtistScreen> {
       );
     }
     
-    // Default error display
     return Card(
       elevation: 0,
       color: colorScheme.errorContainer.withValues(alpha: 0.5),
-      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
+      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
       child: Padding(
         padding: const EdgeInsets.all(16),
         child: Row(

lib/screens/downloaded_album_screen.dart

@@ -0,0 +1,576 @@
+import 'dart:io';
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:cached_network_image/cached_network_image.dart';
+import 'package:open_filex/open_filex.dart';
+import 'package:spotiflac_android/l10n/l10n.dart';
+import 'package:spotiflac_android/utils/mime_utils.dart';
+import 'package:spotiflac_android/providers/download_queue_provider.dart';
+import 'package:spotiflac_android/screens/track_metadata_screen.dart';
+
+/// Screen to display downloaded tracks from a specific album
+class DownloadedAlbumScreen extends ConsumerStatefulWidget {
+  final String albumName;
+  final String artistName;
+  final String? coverUrl;
+
+  const DownloadedAlbumScreen({
+    super.key,
+    required this.albumName,
+    required this.artistName,
+    this.coverUrl,
+  });
+
+  @override
+  ConsumerState<DownloadedAlbumScreen> createState() => _DownloadedAlbumScreenState();
+}
+
+class _DownloadedAlbumScreenState extends ConsumerState<DownloadedAlbumScreen> {
+  // Multi-select state
+  bool _isSelectionMode = false;
+  final Set<String> _selectedIds = {};
+
+  /// Get tracks for this album from history provider (reactive)
+  List<DownloadHistoryItem> _getAlbumTracks(List<DownloadHistoryItem> allItems) {
+    return allItems.where((item) {
+      final itemKey = '${item.albumName}|${item.albumArtist ?? item.artistName}';
+      final albumKey = '${widget.albumName}|${widget.artistName}';
+      return itemKey == albumKey;
+    }).toList()
+      ..sort((a, b) {
+        final aNum = a.trackNumber ?? 999;
+        final bNum = b.trackNumber ?? 999;
+        if (aNum != bNum) return aNum.compareTo(bNum);
+        return a.trackName.compareTo(b.trackName);
+      });
+  }
+
+  void _enterSelectionMode(String itemId) {
+    HapticFeedback.mediumImpact();
+    setState(() {
+      _isSelectionMode = true;
+      _selectedIds.add(itemId);
+    });
+  }
+
+  void _exitSelectionMode() {
+    setState(() {
+      _isSelectionMode = false;
+      _selectedIds.clear();
+    });
+  }
+
+  void _toggleSelection(String itemId) {
+    setState(() {
+      if (_selectedIds.contains(itemId)) {
+        _selectedIds.remove(itemId);
+        if (_selectedIds.isEmpty) {
+          _isSelectionMode = false;
+        }
+      } else {
+        _selectedIds.add(itemId);
+      }
+    });
+  }
+
+  void _selectAll(List<DownloadHistoryItem> tracks) {
+    setState(() {
+      _selectedIds.addAll(tracks.map((e) => e.id));
+    });
+  }
+
+  Future<void> _deleteSelected(List<DownloadHistoryItem> currentTracks) async {
+    final count = _selectedIds.length;
+    final confirmed = await showDialog<bool>(
+      context: context,
+      builder: (ctx) => AlertDialog(
+        title: Text(context.l10n.downloadedAlbumDeleteSelected),
+        content: Text(context.l10n.downloadedAlbumDeleteMessage(count)),
+        actions: [
+          TextButton(
+            onPressed: () => Navigator.pop(ctx, false),
+            child: Text(context.l10n.dialogCancel),
+          ),
+          FilledButton(
+            onPressed: () => Navigator.pop(ctx, true),
+            style: FilledButton.styleFrom(
+              backgroundColor: Theme.of(context).colorScheme.error,
+            ),
+            child: Text(context.l10n.dialogDelete),
+          ),
+        ],
+      ),
+    );
+
+    if (confirmed == true && mounted) {
+      final historyNotifier = ref.read(downloadHistoryProvider.notifier);
+      final idsToDelete = _selectedIds.toList();
+      
+      int deletedCount = 0;
+      for (final id in idsToDelete) {
+        final item = currentTracks.where((e) => e.id == id).firstOrNull;
+        if (item != null) {
+          try {
+            final file = File(item.filePath);
+            if (await file.exists()) {
+              await file.delete();
+            }
+          } catch (_) {}
+          historyNotifier.removeFromHistory(id);
+          deletedCount++;
+        }
+      }
+      
+      _exitSelectionMode();
+      
+      if (mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(content: Text(context.l10n.snackbarDeletedTracks(deletedCount))),
+        );
+      }
+    }
+  }
+
+  Future<void> _openFile(String filePath) async {
+    try {
+      final mimeType = audioMimeTypeForPath(filePath);
+      await OpenFilex.open(filePath, type: mimeType);
+    } catch (e) {
+      if (mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(content: Text(context.l10n.snackbarCannotOpenFile(e.toString()))),
+        );
+      }
+    }
+  }
+
+  void _navigateToMetadataScreen(DownloadHistoryItem item) {
+    Navigator.push(context, PageRouteBuilder(
+      transitionDuration: const Duration(milliseconds: 300),
+      reverseTransitionDuration: const Duration(milliseconds: 250),
+      pageBuilder: (context, animation, secondaryAnimation) => TrackMetadataScreen(item: item),
+      transitionsBuilder: (context, animation, secondaryAnimation, child) => FadeTransition(opacity: animation, child: child),
+    ));
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final colorScheme = Theme.of(context).colorScheme;
+    final bottomPadding = MediaQuery.of(context).padding.bottom;
+    
+    // Watch history and get tracks for this album (reactive!)
+    final allHistoryItems = ref.watch(downloadHistoryProvider.select((s) => s.items));
+    final tracks = _getAlbumTracks(allHistoryItems);
+    
+    // Auto-pop if album has less than 2 tracks (no longer an "album")
+    if (tracks.length < 2) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (mounted) Navigator.pop(context);
+      });
+      return const SizedBox.shrink();
+    }
+    
+    // Clean up selected IDs that no longer exist
+    final validIds = tracks.map((t) => t.id).toSet();
+    _selectedIds.removeWhere((id) => !validIds.contains(id));
+    if (_selectedIds.isEmpty && _isSelectionMode) {
+      WidgetsBinding.instance.addPostFrameCallback((_) {
+        if (mounted) setState(() => _isSelectionMode = false);
+      });
+    }
+
+    return PopScope(
+      canPop: !_isSelectionMode,
+      onPopInvokedWithResult: (didPop, result) {
+        if (!didPop && _isSelectionMode) {
+          _exitSelectionMode();
+        }
+      },
+      child: Scaffold(
+        body: Stack(
+          children: [
+            CustomScrollView(
+              slivers: [
+                _buildAppBar(context, colorScheme),
+                _buildInfoCard(context, colorScheme, tracks),
+                _buildTrackListHeader(context, colorScheme, tracks),
+                _buildTrackList(context, colorScheme, tracks),
+                SliverToBoxAdapter(child: SizedBox(height: _isSelectionMode ? 120 : 32)),
+              ],
+            ),
+            
+            // Bottom Selection Action Bar
+            AnimatedPositioned(
+              duration: const Duration(milliseconds: 250),
+              curve: Curves.easeOutCubic,
+              left: 0,
+              right: 0,
+              bottom: _isSelectionMode ? 0 : -(200 + bottomPadding),
+              child: _buildSelectionBottomBar(context, colorScheme, tracks, bottomPadding),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildAppBar(BuildContext context, ColorScheme colorScheme) {
+    return SliverAppBar(
+      expandedHeight: 280,
+      pinned: true,
+      stretch: true,
+      backgroundColor: colorScheme.surface,
+      surfaceTintColor: Colors.transparent,
+      flexibleSpace: FlexibleSpaceBar(
+        background: Stack(
+          fit: StackFit.expand,
+          children: [
+            if (widget.coverUrl != null)
+              CachedNetworkImage(
+                imageUrl: widget.coverUrl!,
+                fit: BoxFit.cover,
+                color: Colors.black.withValues(alpha: 0.5),
+                colorBlendMode: BlendMode.darken,
+                memCacheWidth: 600,
+              ),
+            Container(
+              decoration: BoxDecoration(
+                gradient: LinearGradient(
+                  begin: Alignment.topCenter,
+                  end: Alignment.bottomCenter,
+                  colors: [
+                    Colors.transparent,
+                    colorScheme.surface.withValues(alpha: 0.8),
+                    colorScheme.surface,
+                  ],
+                  stops: const [0.0, 0.7, 1.0],
+                ),
+              ),
+            ),
+            Center(
+              child: Padding(
+                padding: const EdgeInsets.only(top: 60),
+                child: Container(
+                  width: 140,
+                  height: 140,
+                  decoration: BoxDecoration(
+                    borderRadius: BorderRadius.circular(16),
+                    boxShadow: [
+                      BoxShadow(
+                        color: Colors.black.withValues(alpha: 0.3),
+                        blurRadius: 20,
+                        offset: const Offset(0, 10),
+                      ),
+                    ],
+                  ),
+                  child: ClipRRect(
+                    borderRadius: BorderRadius.circular(16),
+                    child: widget.coverUrl != null
+                        ? CachedNetworkImage(imageUrl: widget.coverUrl!, fit: BoxFit.cover, memCacheWidth: 280)
+                        : Container(
+                            color: colorScheme.surfaceContainerHighest,
+                            child: Icon(Icons.album, size: 48, color: colorScheme.onSurfaceVariant),
+                          ),
+                  ),
+                ),
+              ),
+            ),
+          ],
+        ),
+        stretchModes: const [StretchMode.zoomBackground, StretchMode.blurBackground],
+      ),
+      leading: IconButton(
+        icon: Container(
+          padding: const EdgeInsets.all(8),
+          decoration: BoxDecoration(color: colorScheme.surface.withValues(alpha: 0.8), shape: BoxShape.circle),
+          child: Icon(Icons.arrow_back, color: colorScheme.onSurface),
+        ),
+        onPressed: () => Navigator.pop(context),
+      ),
+    );
+  }
+
+  Widget _buildInfoCard(BuildContext context, ColorScheme colorScheme, List<DownloadHistoryItem> tracks) {
+    return SliverToBoxAdapter(
+      child: Padding(
+        padding: const EdgeInsets.all(16),
+        child: Card(
+          elevation: 0,
+          color: colorScheme.surfaceContainerLow,
+          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
+          child: Padding(
+            padding: const EdgeInsets.all(20),
+            child: Column(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Text(
+                  widget.albumName,
+                  style: Theme.of(context).textTheme.headlineSmall?.copyWith(fontWeight: FontWeight.bold, color: colorScheme.onSurface),
+                ),
+                const SizedBox(height: 4),
+                Text(
+                  widget.artistName,
+                  style: Theme.of(context).textTheme.bodyLarge?.copyWith(color: colorScheme.onSurfaceVariant),
+                ),
+                const SizedBox(height: 12),
+                Row(
+                  children: [
+                    Container(
+                      padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
+                      decoration: BoxDecoration(color: colorScheme.primaryContainer, borderRadius: BorderRadius.circular(20)),
+                      child: Row(
+                        mainAxisSize: MainAxisSize.min,
+                        children: [
+                          Icon(Icons.download_done, size: 14, color: colorScheme.onPrimaryContainer),
+                          const SizedBox(width: 4),
+                          Text(context.l10n.downloadedAlbumDownloadedCount(tracks.length), style: TextStyle(color: colorScheme.onPrimaryContainer, fontWeight: FontWeight.w600, fontSize: 12)),
+                        ],
+                      ),
+                    ),
+                    const SizedBox(width: 8),
+                    if (_getCommonQuality(tracks) != null)
+                      Container(
+                        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
+                        decoration: BoxDecoration(
+                          color: _getCommonQuality(tracks)!.startsWith('24') 
+                              ? colorScheme.tertiaryContainer 
+                              : colorScheme.surfaceContainerHighest,
+                          borderRadius: BorderRadius.circular(20),
+                        ),
+                        child: Text(
+                          _getCommonQuality(tracks)!,
+                          style: TextStyle(
+                            color: _getCommonQuality(tracks)!.startsWith('24') 
+                                ? colorScheme.onTertiaryContainer 
+                                : colorScheme.onSurfaceVariant,
+                            fontWeight: FontWeight.w600,
+                            fontSize: 12,
+                          ),
+                        ),
+                      ),
+                  ],
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  String? _getCommonQuality(List<DownloadHistoryItem> tracks) {
+    if (tracks.isEmpty) return null;
+    final firstQuality = tracks.first.quality;
+    if (firstQuality == null) return null;
+    for (final track in tracks) {
+      if (track.quality != firstQuality) return null;
+    }
+    return firstQuality;
+  }
+
+  Widget _buildTrackListHeader(BuildContext context, ColorScheme colorScheme, List<DownloadHistoryItem> tracks) {
+    return SliverToBoxAdapter(
+      child: Padding(
+        padding: const EdgeInsets.fromLTRB(20, 8, 20, 8),
+        child: Row(
+          children: [
+            Icon(Icons.queue_music, size: 20, color: colorScheme.primary),
+            const SizedBox(width: 8),
+            Text(context.l10n.downloadedAlbumTracksHeader, style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.w600, color: colorScheme.onSurface)),
+            const Spacer(),
+            if (!_isSelectionMode)
+              TextButton.icon(
+                onPressed: tracks.isNotEmpty ? () => _enterSelectionMode(tracks.first.id) : null,
+                icon: const Icon(Icons.checklist, size: 18),
+                label: Text(context.l10n.actionSelect),
+                style: TextButton.styleFrom(visualDensity: VisualDensity.compact),
+              ),
+          ],
+        ),
+      ),
+    );
+  }
+
+  Widget _buildTrackList(BuildContext context, ColorScheme colorScheme, List<DownloadHistoryItem> tracks) {
+    return SliverList(
+      delegate: SliverChildBuilderDelegate(
+        (context, index) {
+          final track = tracks[index];
+          return KeyedSubtree(
+            key: ValueKey(track.id),
+            child: _buildTrackItem(context, colorScheme, track),
+          );
+        },
+        childCount: tracks.length,
+      ),
+    );
+  }
+
+  Widget _buildTrackItem(BuildContext context, ColorScheme colorScheme, DownloadHistoryItem track) {
+    final isSelected = _selectedIds.contains(track.id);
+    
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: 8),
+      child: Card(
+        elevation: 0,
+        color: isSelected ? colorScheme.primaryContainer.withValues(alpha: 0.3) : Colors.transparent,
+        margin: const EdgeInsets.symmetric(vertical: 2),
+        child: ListTile(
+          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
+          onTap: _isSelectionMode 
+              ? () => _toggleSelection(track.id)
+              : () => _navigateToMetadataScreen(track),
+          onLongPress: _isSelectionMode ? null : () => _enterSelectionMode(track.id),
+          leading: Row(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              if (_isSelectionMode) ...[
+                Container(
+                  width: 24,
+                  height: 24,
+                  decoration: BoxDecoration(
+                    color: isSelected ? colorScheme.primary : Colors.transparent,
+                    shape: BoxShape.circle,
+                    border: Border.all(color: isSelected ? colorScheme.primary : colorScheme.outline, width: 2),
+                  ),
+                  child: isSelected 
+                      ? Icon(Icons.check, color: colorScheme.onPrimary, size: 16)
+                      : null,
+                ),
+                const SizedBox(width: 12),
+              ],
+              SizedBox(
+                width: 24,
+                child: Text(
+                  track.trackNumber?.toString() ?? '-',
+                  style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+                    color: colorScheme.onSurfaceVariant,
+                    fontWeight: FontWeight.w500,
+                  ),
+                  textAlign: TextAlign.center,
+                ),
+              ),
+            ],
+          ),
+          title: Text(
+            track.trackName,
+            maxLines: 1,
+            overflow: TextOverflow.ellipsis,
+            style: Theme.of(context).textTheme.bodyLarge?.copyWith(fontWeight: FontWeight.w500),
+          ),
+          subtitle: Text(
+            track.artistName,
+            maxLines: 1,
+            overflow: TextOverflow.ellipsis,
+            style: TextStyle(color: colorScheme.onSurfaceVariant),
+          ),
+          trailing: _isSelectionMode ? null : IconButton(
+            onPressed: () => _openFile(track.filePath),
+            icon: Icon(Icons.play_arrow, color: colorScheme.primary),
+            style: IconButton.styleFrom(
+              backgroundColor: colorScheme.primaryContainer.withValues(alpha: 0.3),
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildSelectionBottomBar(BuildContext context, ColorScheme colorScheme, List<DownloadHistoryItem> tracks, double bottomPadding) {
+    final selectedCount = _selectedIds.length;
+    final allSelected = selectedCount == tracks.length && tracks.isNotEmpty;
+    
+    return Container(
+      decoration: BoxDecoration(
+        color: colorScheme.surfaceContainerHigh,
+        borderRadius: const BorderRadius.vertical(top: Radius.circular(28)),
+        boxShadow: [
+          BoxShadow(
+            color: Colors.black.withValues(alpha: 0.15),
+            blurRadius: 12,
+            offset: const Offset(0, -4),
+          ),
+        ],
+      ),
+      child: SafeArea(
+        top: false,
+        child: Padding(
+          padding: EdgeInsets.fromLTRB(16, 16, 16, bottomPadding > 0 ? 8 : 16),
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              Container(
+                width: 32,
+                height: 4,
+                margin: const EdgeInsets.only(bottom: 16),
+                decoration: BoxDecoration(
+                  color: colorScheme.outlineVariant,
+                  borderRadius: BorderRadius.circular(2),
+                ),
+              ),
+              Row(
+                children: [
+                  IconButton.filledTonal(
+                    onPressed: _exitSelectionMode,
+                    icon: const Icon(Icons.close),
+                    style: IconButton.styleFrom(
+                      backgroundColor: colorScheme.surfaceContainerHighest,
+                    ),
+                  ),
+                  const SizedBox(width: 12),
+                  Expanded(
+                    child: Column(
+                      crossAxisAlignment: CrossAxisAlignment.start,
+                      children: [
+                        Text(
+                          context.l10n.downloadedAlbumSelectedCount(selectedCount),
+                          style: Theme.of(context).textTheme.titleMedium?.copyWith(fontWeight: FontWeight.bold),
+                        ),
+                        Text(
+                          allSelected ? context.l10n.downloadedAlbumAllSelected : context.l10n.downloadedAlbumTapToSelect,
+                          style: Theme.of(context).textTheme.bodySmall?.copyWith(color: colorScheme.onSurfaceVariant),
+                        ),
+                      ],
+                    ),
+                  ),
+                  TextButton.icon(
+                    onPressed: () {
+                      if (allSelected) {
+                        _exitSelectionMode();
+                      } else {
+                        _selectAll(tracks);
+                      }
+                    },
+                    icon: Icon(allSelected ? Icons.deselect : Icons.select_all, size: 20),
+                    label: Text(allSelected ? context.l10n.actionDeselect : context.l10n.actionSelectAll),
+                    style: TextButton.styleFrom(foregroundColor: colorScheme.primary),
+                  ),
+                ],
+              ),
+              const SizedBox(height: 16),
+              SizedBox(
+                width: double.infinity,
+                child: FilledButton.icon(
+                  onPressed: selectedCount > 0 ? () => _deleteSelected(tracks) : null,
+                  icon: const Icon(Icons.delete_outline),
+                  label: Text(
+                    selectedCount > 0 
+                        ? context.l10n.downloadedAlbumDeleteCount(selectedCount)
+                        : context.l10n.downloadedAlbumSelectToDelete,
+                  ),
+                  style: FilledButton.styleFrom(
+                    backgroundColor: selectedCount > 0 ? colorScheme.error : colorScheme.surfaceContainerHighest,
+                    foregroundColor: selectedCount > 0 ? colorScheme.onError : colorScheme.onSurfaceVariant,
+                    padding: const EdgeInsets.symmetric(vertical: 16),
+                    shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
+                  ),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}

lib/screens/home_screen.dart

@@ -6,6 +6,8 @@ import 'package:cached_network_image/cached_network_image.dart';
 import 'package:spotiflac_android/providers/track_provider.dart';
 import 'package:spotiflac_android/providers/download_queue_provider.dart';
 import 'package:spotiflac_android/providers/settings_provider.dart';
+import 'package:spotiflac_android/models/track.dart';
+import 'package:spotiflac_android/services/platform_bridge.dart';
 
 class HomeScreen extends ConsumerStatefulWidget {
   const HomeScreen({super.key});
@@ -267,6 +269,23 @@ class _HomeScreenState extends ConsumerState<HomeScreen> {
 
   Widget _buildTrackTile(int index, ColorScheme colorScheme) {
     final track = ref.watch(trackProvider).tracks[index];
+    final isCollection = track.isCollection;
+    
+    // Determine subtitle text based on item type
+    String subtitleText;
+    if (isCollection) {
+      final typeLabel = track.albumType ?? (track.isPlaylistItem ? 'Playlist' : 'Album');
+      final capitalizedType = typeLabel.isNotEmpty 
+          ? '${typeLabel[0].toUpperCase()}${typeLabel.substring(1)}' 
+          : 'Album';
+      final year = track.releaseDate != null && track.releaseDate!.length >= 4
+          ? track.releaseDate!.substring(0, 4) 
+          : '';
+      subtitleText = '$capitalizedType • ${track.artistName}${year.isNotEmpty ? ' • $year' : ''}';
+    } else {
+      subtitleText = track.artistName;
+    }
+    
     return ListTile(
       leading: track.coverUrl != null
           ? ClipRRect(
@@ -285,22 +304,87 @@ class _HomeScreenState extends ConsumerState<HomeScreen> {
                 color: colorScheme.surfaceContainerHighest,
                 borderRadius: BorderRadius.circular(8),
               ),
-              child: Icon(Icons.music_note, color: colorScheme.onSurfaceVariant),
+              child: Icon(
+                isCollection ? Icons.album : Icons.music_note, 
+                color: colorScheme.onSurfaceVariant,
+              ),
             ),
       title: Text(track.name, maxLines: 1, overflow: TextOverflow.ellipsis),
       subtitle: Text(
-        track.artistName, 
+        subtitleText, 
         maxLines: 1, 
         overflow: TextOverflow.ellipsis,
         style: TextStyle(color: colorScheme.onSurfaceVariant),
       ),
-      trailing: Text(
+      trailing: isCollection 
-        _formatDuration(track.duration),
+          ? Icon(Icons.chevron_right, color: colorScheme.onSurfaceVariant)
-        style: Theme.of(context).textTheme.bodyMedium?.copyWith(
+          : Text(
-          color: colorScheme.onSurfaceVariant,
+              _formatDuration(track.duration),
-        ),
+              style: Theme.of(context).textTheme.bodyMedium?.copyWith(
-      ),
+                color: colorScheme.onSurfaceVariant,
-      onTap: () => _downloadTrack(index),
+              ),
+            ),
+      onTap: () => isCollection ? _openCollection(track) : _downloadTrack(index),
+    );
+  }
+  
+  Future<void> _openCollection(Track track) async {
+    // Get the extension ID from the track source
+    final extensionId = track.source;
+    if (extensionId == null) return;
+    
+    // Fetch album/playlist tracks using the extension
+    try {
+      if (track.isAlbumItem) {
+        final albumData = await PlatformBridge.getAlbumWithExtension(extensionId, track.id);
+        if (albumData != null && mounted) {
+          final trackList = albumData['tracks'] as List<dynamic>? ?? [];
+          final tracks = trackList.map((t) => _parseExtensionTrack(t as Map<String, dynamic>, extensionId)).toList();
+          ref.read(trackProvider.notifier).setTracksFromCollection(
+            tracks: tracks,
+            albumName: albumData['name'] as String? ?? track.name,
+            coverUrl: albumData['cover_url'] as String? ?? track.coverUrl,
+          );
+        }
+      } else if (track.isPlaylistItem) {
+        final playlistData = await PlatformBridge.getPlaylistWithExtension(extensionId, track.id);
+        if (playlistData != null && mounted) {
+          final trackList = playlistData['tracks'] as List<dynamic>? ?? [];
+          final tracks = trackList.map((t) => _parseExtensionTrack(t as Map<String, dynamic>, extensionId)).toList();
+          ref.read(trackProvider.notifier).setTracksFromCollection(
+            tracks: tracks,
+            playlistName: playlistData['name'] as String? ?? track.name,
+            coverUrl: playlistData['cover_url'] as String? ?? track.coverUrl,
+          );
+        }
+      }
+    } catch (e) {
+      if (mounted) {
+        ScaffoldMessenger.of(context).showSnackBar(
+          SnackBar(content: Text('Failed to load: $e')),
+        );
+      }
+    }
+  }
+  
+  Track _parseExtensionTrack(Map<String, dynamic> data, String source) {
+    int durationMs = 0;
+    final durationValue = data['duration_ms'];
+    if (durationValue is int) {
+      durationMs = durationValue;
+    } else if (durationValue is double) {
+      durationMs = durationValue.toInt();
+    }
+    
+    return Track(
+      id: (data['id'] ?? '').toString(),
+      name: (data['name'] ?? '').toString(),
+      artistName: (data['artists'] ?? '').toString(),
+      albumName: (data['album_name'] ?? '').toString(),
+      coverUrl: (data['cover_url'] ?? data['images'])?.toString(),
+      duration: (durationMs / 1000).round(),
+      releaseDate: data['release_date']?.toString(),
+      source: source,
     );
   }