Go backend:
- Add AudioCodec field to DownloadResult and DownloadResponse
- Extension download results can now include audio_codec/audioCodec
- ffmpegGetInfo and probeAudioQuality now return codec field
- Add trackItemBytes option to file.download() for custom progress handling
Flutter:
- Check audio_codec before container conversion
- Skip FLAC conversion if source codec is lossy (AAC, MP3, Opus, etc.)
- Prevents fake upscale from lossy to lossless containers
- Extract _formatDownloadProgressLabel() for cleaner code
- Show received/total size when bytesTotal is available
- Estimate total size from progress when only bytesReceived is known
- Add text overflow handling with ellipsis
New lyrics providers using Paxsenix API:
- Spotify: Synced lyrics from Spotify
- Deezer: Synced lyrics from Deezer
- YouTube: Lyrics from YouTube
- Kugou: Lyrics from Kugou (Chinese service)
- Genius: Plain text lyrics from Genius
Implementation:
- Add lyrics client implementations for all providers
- Smart search result scoring based on track name, artist, and duration
- Support for both synced (LRC) and unsynced lyrics formats
- Fallback search with simplified track names and primary artist
UI updates:
- Add provider entries to lyrics priority settings page
- Add display names for new providers in settings
FFmpeg doesn't always embed lyrics correctly to MP3 files. This adds
manual ID3v2.3 USLT (Unsynchronized Lyrics) frame writing after FFmpeg
metadata embedding to ensure lyrics are properly stored.
Implementation:
- Extract lyrics from metadata (UNSYNCEDLYRICS or LYRICS key)
- Build ID3v2.3 compliant USLT frame with UTF-16LE encoding
- Insert or replace USLT frame in existing ID3v2.3 tag
- Create new ID3v2.3 tag if file has no ID3 header
- Skip gracefully for unsupported ID3 versions or flags
Also includes minor audio analysis improvements:
- Consistent dynamic range calculation (peak - rms)
- Filter out 'unknown' and 'n/a' labels
- Add -vn -sn -dn flags for more robust stream selection
Audio Analysis Enhancements:
- Display codec name and container format
- Show decoded sample format (s16, s32, fltp, etc.)
- Add LUFS integrated loudness measurement (broadcast standard)
- Add true peak measurement (dBTP)
- Detect and count clipping samples per channel
- Estimate spectral cutoff frequency (helps detect fake upscales)
- Show per-channel statistics (Peak, RMS, DR, Clip count)
UI Improvements:
- MetricChip now handles long text with ellipsis
- Constrained max width for better layout
Cache version bumped to 4 to force rescan with new metrics.
- Replace inline format detection with convertibleAudioSourceFormat()
- Replace inline conversion rules with canConvertAudioFormat()
- Add unit tests for Dolby format detection and conversion rules
Audio Analysis:
- Add rescan capability by bumping cache version
- Display channel layout (stereo, 5.1, etc.) and bitrate
- Use astats filter for more accurate peak/RMS measurements
- Support more formats: mp4, ac3, eac3, mka, wv, ape, tta, aif
- Only report bit depth for codecs that store it (FLAC, ALAC, WAV)
- Validate cache for SAF content:// URIs
Conversion:
- Add AAC as conversion target format
- Recognize ALAC as lossless source
- Prevent accidental deletion when source and target URI match
- Store format and bitrate in database after conversion
Utilities:
- Add audio_conversion_utils.dart for centralized conversion logic
- Add isSameContentUri() helper for safe URI comparison
The HIGH-quality lossy format picker can now produce an AAC/M4A 320 kbps output alongside MP3 and Opus. FFmpegService.convertM4aToLossy/convertAudioFormat, the Dart queue pipeline, the Kotlin finalizer, and the library database format helper all route .m4a through a unified aac codec path and tag the resulting file with the M4A metadata writer. The Lossy Format setting gains a new option, and the track metadata convert dialog lists AAC next to the other targets.
Apple Music lyrics gain a 'eLRC word sync' switch (default off). When disabled the pax-to-LRC formatter strips inline word timestamps, producing line-synced LRC that is safer for players that choke on eLRC; enabling it restores the previous word-by-word behaviour. The change propagates through SetLyricsFetchOptions and invalidates the global lyrics cache on toggle.
Broad l10n migration: roughly 400 previously hardcoded English strings across queue, settings, track metadata, repo, audio analysis, setup and extension screens now live in the ARB catalog, with matching plural/placeholder forms. No behaviour change beyond localisation. Existing and new unit tests (lyrics eLRC toggle and Dart settings round-trip) pass.
Introduce AppRemoteConfigService which fetches a platform/version/locale-aware JSON payload from api.zarz.moe/v1/spotiflac-mobile/config and caches it in SharedPreferences. main_shell shows a one-shot announcement dialog (respecting dismissible, CTA, time window and version gates) when no update prompt is pending; dismissed IDs are persisted so each announcement surfaces only once.
Tweaks bundled in: the service health dot loses its blur halo in favour of solid Material 3 tones, and AppInfo gains the remote config endpoint constant. The share listener and SAF migration hook stay synchronous inside the post-frame callback so share-intent URLs never race the network-bound checks.
New unit tests cover the announcement CTA/active-window rules.
The SAF and local post-download branches used to rush an ffmpeg 'M4A to FLAC' remux whenever the output extension was .flac, which silently upscaled AAC or EAC3 streams into a lossless container. Each branch now mirrors the native worker by probing the primary audio codec before converting: lossless sources (and true FLAC-in-MP4 files) stay in their native container with the right extension, while genuine ALAC/WAV payloads still get remuxed.
Add an outputExt field to DownloadRequestPayload so the Go backend always knows the user-requested container, and use it together with _shouldRequestContainerConversion to pick the right behaviour for shouldPreserveNativeM4a and the Kotlin finalizer. Decryption descriptors no longer force M4A preservation on their own; the codec probe already makes that call correctly.
Bump the history schema on both the Kotlin finalizer and the Dart database to v9, adding bitrate (kbps) and format (codec label) columns, and let the download flow fill them from backend/probe metadata so lossy downloads keep a 'AAC 256kbps' label instead of falling back to the stored placeholder. Library filtering and the track metadata screen now read format/bitrate directly from those columns, which also fixes mis-tagged quality badges after re-downloading a track at a different format.
Additional fixes bundled in: EditFileMetadata now routes ReplayGain writes through the M4A path whenever the file starts with ftyp (fixing .flac files that actually hold MP4 containers); GetM4AQuality falls back to the first trak/mdia/mdhd duration when mvhd is zero so EAC3 streams no longer report 0s; and both Kotlin and Dart reject bitrate values below 16 kbps to prevent probe noise from surfacing as '0 kbps' labels. New unit tests cover the EAC3 mdhd fallback and the mis-named M4A replaygain path.
GetM4AQuality now recognizes fLaC, alac, ec-3, ac-3, and ac-4 sample entries and parses the MP4 FLACSpecificBox so library entries carry the real codec rather than the container extension. The AudioQuality struct exposes Codec and Bitrate fields (with an estimator for compressed streams), and ReadFileMetadata publishes format + audio_codec so Flutter and Kotlin can make format decisions based on the actual stream.
Downstream: library_scan labels M4A-family items as flac/alac/eac3/ac3/ac4/m4a, zeroes the bitrate for lossless formats, and the filter UI + quality badges use the codec-derived format instead of only the file extension. Scans and SAF importers also accept .mp4 and .aac file extensions. New unit tests cover codec name mapping and MP4 FLACSpecificBox decoding.
The audio analysis card used to read from a persistent cache but offered no way to refresh the result when the underlying file had been re-downloaded at a different quality (for example, re-downloading a track as FLAC after capturing it as AAC). Add an explicit rescan control that clears the cached JSON + spectrogram, reruns the FFmpeg probe and analysis pipeline, and swaps in the fresh data while keeping the loading copy distinct from first-run analysis. A retry button is also exposed in the error card so transient failures do not require navigating away.
All audio_analysis strings now have a Re-analyze / Re-analyzing pair in the ARB catalog so every locale can translate them independently.
Add a pair of floating quick-scroll buttons on the library tab so long lists become easier to navigate. The buttons sit above the bottom navigation (or the selection toolbar in selection mode), fade in and out based on the active page's scroll metrics, and share their scroll-target keys per filter mode so switching filters does not carry over the previous page's scroll state.
Downloads from providers that stream FLAC inside an fMP4 container (e.g. Amazon Music) were being written to disk with a .flac extension while the payload still carried ISO-BMFF atoms. The container-conversion guard then saw codec=flac and skipped the remux, leaving native FLAC tag writers to fail with 'fLaC head incorrect'.
Force '-f flac' on the decryption command whenever the target extension is .flac so FFmpeg emits a real FLAC stream, and add an 'fLaC' magic-byte probe on both the Dart and Kotlin container-conversion guards so a FLAC-in-MP4 source is remuxed rather than silently passed through as a tag-writer hazard.
GetM4AQuality previously defaulted to 16-bit whenever the audio sample entry was not ALAC, which silently labeled lossy AAC downloads as CD quality in the library and in extension APIs. Only fill BitDepth when the atom is ALAC (including the ALACSpecificConfig refinement), and leave it as zero for AAC/mp4a, matching how the MP3 and Opus probes already report lossy sources. Tests cover both the ALAC and AAC branches.
The native-worker container conversion used to remux any .m4a download to .flac whenever the user requested a FLAC output, which silently upgraded lossy AAC streams to a FLAC container without adding any information. Guard the remux with an FFmpeg/FFprobe codec probe on both the Dart and Kotlin finalization paths so only genuinely lossless sources (ALAC, WavPack, PCM, etc.) are converted, and expose a requires_container_conversion capability so extensions can force conversion when they know the source is lossless.
When the native worker result advertises a requested non-FLAC output extension (for example '.m4a'), skip the m4a-to-flac container conversion in both the Dart and Kotlin finalizers so the native output container is preserved end-to-end.
- ffmpeg_service: propagate the top-level 'output_extension' hint into the download-result descriptor for both the map-backed and legacy paths; expose a normalized getter for consistent comparisons.
- download_queue_provider: short-circuit the native-worker container-conversion step when the descriptor's requested extension is not '.flac', with a debug log describing the skip.
- NativeDownloadFinalizer: mirror the guard on the Kotlin side so the finalizer does not force a container conversion that would clobber the requested native output.
Staged SAF outputs and library-scan partials now share a single naming pattern: '<name>.partial' regardless of the audio extension. The previous '<name>.partial.<ext>' form caused SAF / media-scanner to surface half-written files as valid audio.
- SafDownloadHandler: force 'application/octet-stream' MIME for staged docs and collapse buildStagedSafFileName to '<name>.partial'. Keep the legacy form behind buildLegacyStagedSafFileName and sweep both via deleteStaleStagedFiles so upgrades clean old residue.
- library_scan: add isLibraryStagingFile that skips both the new and legacy partial patterns during collectLibraryAudioFiles so residual staging files never show up in the library.
- library_scan_supplement_test: seed both legacy and new partial files and assert they are ignored by the scanner.
Use the 3-arg startForeground overload with FOREGROUND_SERVICE_TYPE_DATA_SYNC on API 29+ so the runtime FGS type matches the manifest declaration. Silences the ForegroundServiceTypeLoggerModule warning on targetSdk 36.
Prevent premature 'downloading' status before actual byte transfer
starts, and cache async provider values to avoid UI flicker during
queue library reloads.
Progress pipeline:
- StartItemProgress now initializes with 'preparing' status instead
of 'downloading'
- SetItemProgress ignores synthetic pre-download progress updates
while status is still 'preparing' (no byte data yet)
- DownloadService reads backend status field and propagates preparing/
downloading/finalizing to native worker item snapshot
- Dart progress stream maps 'preparing' to DownloadStatus.downloading
with progress 0.0 (indeterminate spinner)
Queue tab:
- Add _queueLibraryCountsCache and _queueLibraryPageDataCache to
retain last successful data during FutureProvider refetches
- Prevents empty-state flash when loadedIndexVersion bumps trigger
provider invalidation
- Caches trimmed to max 24 entries via FIFO eviction
Align the Kotlin-side history database contract with the Dart-side
schema v8 changes from the previous commit.
- Bump HISTORY_SCHEMA_VERSION from 5 to 8
- Add spotify_id_norm, isrc_norm, match_key normalized columns to
CREATE TABLE and ensureHistoryColumn calls
- Create history_path_keys table with item_id/path_key composite key
- Backfill normalized columns and path keys on first v8 open
- Populate normalized columns in putNormalizedHistoryColumns when
building history rows
- Update deleteDuplicateHistoryRows to also clean history_path_keys
- Call replaceHistoryPathKeys after history row insert
- Implement buildPathMatchKeys in Kotlin mirroring the Dart version:
URI parsing, backslash normalization, percent decoding, Android
storage path aliases, audio extension stripping
Replace in-memory list merging in the queue tab with fully database-
backed pagination using ATTACH DATABASE to join library and history
tables in a single UNION ALL query.
Queue tab:
- Remove localLibraryAllItemsProvider and _queueHistoryStatsProvider
- Add _queueLibraryPageProvider and _queueLibraryCountsProvider backed
by LibraryDatabase.getQueueTrackPage/getQueueCounts/getQueueAlbumPage
- Implement infinite scroll via _handleLibraryScrollNotification with
_libraryPageLimit growing by 300 per batch
- Album/single/total counts computed via SQL GROUP BY aggregates
History database (v5 -> v8):
- v6: add idx_history_track_artist index
- v7: add history_path_keys table for cross-DB dedup, backfill from
existing rows
- v8: add spotify_id_norm, isrc_norm, match_key normalized columns
with indexes, backfill from existing data
- Add getAlbumTracks, findByTrackAndArtist, getGroupedCounts,
existsTrack, findExistingTrack, existingTrackKeys batch lookup
- deleteBySpotifyId now returns deleted count for accurate totalCount
- All write paths maintain history_path_keys consistency
Library database (v7 -> v8):
- v8: add library_path_keys table for cross-DB dedup
- Add getQueueTrackPage, getQueueCounts, getQueueAlbumPage with
ATTACH DATABASE for cross-DB UNION ALL queries
- Dedup local items against history via path_keys JOIN
- All write/delete paths maintain library_path_keys consistency
Download history provider:
- Load only 100 recent items into state.items at startup
- Store lookupItems as immutable List field instead of recomputing
from maps on every access
- Add async fallback to DB in _putInMemoryHistory for items outside
the 100-item window
- Add downloadHistoryPageProvider, downloadHistoryGroupedCountsProvider,
downloadedAlbumTracksProvider, downloadHistoryBatchExistsProvider
- Add catchError to adoptNativeHistoryItem async block
- Fix removeBySpotifyId to query actual DB count instead of decrement
Screen migrations:
- album/artist/playlist/home screens use async DB lookups instead of
sync in-memory state for track existence and playback resolution
- downloaded_album_screen uses downloadedAlbumTracksProvider
- library_tracks_folder_screen uses downloadHistoryBatchExistsProvider
for skip-downloaded checks and cover resolution
Replace the full in-memory List<LocalLibraryItem> in LocalLibraryState
with a lightweight lookup index (ISRCs, matchKeys, filePathById) and
database-backed FutureProvider.family pagination providers.
Database changes:
- Add library schema v7 with normalized lookup columns (track_name_norm,
artist_name_norm, album_name_norm, album_artist_norm, match_key,
album_key) and corresponding indexes
- Backfill normalized columns on migration from v6
- Add getPage, getPageCount, getAlbumPage, getAlbumCount, getLookupIndex,
getCoverPaths, getByFilePath, findFirstByTrackAndArtist DB methods
Provider changes:
- LocalLibraryState no longer holds items list; uses totalCount and
loadedIndexVersion for change tracking
- Deprecate synchronous getByIsrc/findByTrackAndArtist (return null);
add async findExistingAsync, getByIsrcAsync, getById on notifier
- Add localLibraryPageProvider, localLibraryAlbumPageProvider,
localLibraryAllItemsProvider family providers for paginated access
- Add localLibraryCoverProvider and localLibraryFirstCoverProvider
for async cover path resolution from DB
Screen migrations:
- album/artist/playlist screens use findExistingAsync for playback
- library_tracks_folder_screen uses async cover providers and
existsInLibrary for local library indicator
- queue_tab watches localLibraryAllItemsProvider instead of state.items
- library_settings_page uses state.totalCount
- playback_provider uses findExistingAsync
Track metadata screen:
- Replace pushReplacement navigation with in-place state swap using
AnimatedSwitcher for smooth cross-fade transitions on track swipe
- Add metadataLoadGeneration counter to prevent stale async callbacks
- Reset all transient state (lyrics, cover, file check) on track change
Long track names (especially CJK/emoji) could exceed filesystem limits
when used as SAF document display names, causing write failures.
- Add truncateUtf8Bytes in Go, Kotlin (MainActivity + SafDownloadHandler),
and Dart to truncate strings at valid UTF-8 codepoint boundaries
- Limit SAF filenames to 180 UTF-8 bytes (preserving file extension)
- Limit SAF directory segments to 120 UTF-8 bytes
- Fix Go sanitizeFilename to use UTF-8 aware truncation instead of
byte slice which could split multi-byte characters
- Add Go test for multi-byte truncation correctness
- Sanitize SAF relative directory in Dart native worker and regular
download paths via _sanitizeSafRelativeDir
Enhance the NativeDownloadFinalizer metadata pipeline and download
service notification accuracy.
Metadata embedding:
- Adopt result > track > request priority chain consistently across
all metadata fields via resultString/trackString/requestString helpers
- Add cover art embedding for FLAC (via cover_path in editFileMetadata)
and M4A (via FFmpeg attached_pic) during native finalization
- Use separate track_number/track_total/disc_number/disc_total fields
for FLAC instead of combined N/M format strings
- Use 'organization' key instead of 'label' for M4A metadata (MP4 std)
- Sanitize literal "null" strings in metadata via cleanMetadataString
- Add -map_metadata 0 to FFmpeg tag commands to preserve existing tags
Notification progress:
- Fall back to percentage-based notification when extension reports
progress ratio without byte counts (bytesTotal == 0)
- Show indeterminate progress spinner during downloading state with
no byte data instead of a stale bar
UI and UX improvements across the library and queue screens.
- Add pinch-to-zoom for library grid views with animated extent
transitions via _AnimatedLibrarySliverGrid widget
- Replace fixed grid column count with responsive maxCrossAxisExtent
- Add smooth fade-in for cover images (local files via frameBuilder,
network via CachedCoverImage fadeInDuration/fadeOutDuration params)
- Refactor track metadata swipe navigation from push+pop to
pushReplacement to prevent route stack accumulation
- Convert adjacentHorizontalPageRoute to MaterialPageRoute subclass
to support pushReplacement with proper transition semantics
- Add five new metadata completeness filters: missing track number,
missing disc number, missing artist, incorrect ISRC format, and
missing label
- Expose trackNumber, discNumber, isrc, and label on
UnifiedLibraryItem for filter support
- Tighten metadata completeness definition to include all new fields
All search, metadata, and download providers are now exclusively
supplied by extensions. The built-in provider registry that previously
exposed Deezer/Tidal/Qobuz as hardcoded providers is fully removed.
Removed across Go, Dart, Kotlin, and Swift:
- BuiltInProviderSpec class, registry, and all accessor helpers
- SearchProviderAllJSON, GetBuiltInProvidersJSON, ParseProviderURLJSON,
ParseDeezerURLExport Go exports and their platform channel bindings
- Built-in provider items in search dropdown, service picker, and
provider priority UI lists
- provider_ui_utils.dart helper file
Deezer metadata enrichment (ISRC lookup, extended metadata, cover
upgrade) remains fully functional through direct DeezerClient calls
in the download pipeline — these are not part of the provider
registry and are unaffected.
Mark deezer as a retired built-in metadata provider so stale user
priority lists are cleaned up on next launch.
Replace full-queue snapshot writes on every progress tick with a
lightweight delta mode that only includes the active item.
- Progress tick (1s loop) now writes item_delta with only the
active item instead of serializing the entire queue
- Full compact_items snapshots are reserved for important events:
start, pause/resume/cancel, item boundaries, finish, and
service stop/destroy
- Compact items omit large static fields (item_json, track_name,
artist_name) that Dart already has from queue restore
- Snapshot always carries item_ids for adoption correlation
- Dart-side _applyAndroidNativeWorkerSnapshot handles item_delta
as a single-item fallback when items array is absent
- Dart-side _tryAdoptAndroidNativeWorkerSnapshot reads item_ids
as fallback when items is not present
- Add deferred SAF publish: native worker writes to cache, runs
all finalization locally, then publishes once to SAF at the end
- Forward defer_saf_publish through DownloadRequestPayload
Introduce a service-owned download worker that offloads the full
download-and-finalize pipeline to DownloadService on Android, keeping
downloads alive independently of the Flutter UI process.
Key changes:
- Extract SAF download logic from MainActivity into SafDownloadHandler
- Add NativeDownloadFinalizer for Kotlin-side decryption, format
conversion, metadata embedding, ReplayGain, post-processing, and
history persistence
- Extend DownloadService with native queue management (start, pause,
resume, cancel) using coroutine-based worker with AtomicFile snapshots
- Add Dart-side orchestration: snapshot polling, run-id correlation,
adoption on app restart, and fallback to Dart queue
- Forward embedReplayGain, tidalHighFormat, and postProcessingEnabled
through Go backend DownloadRequest struct
- Add nativeDownloadWorkerEnabled setting with UI toggle
- Make DownloadQueueLookup collections unmodifiable
zarzet