Selecting a subtitle on Android did nothing. The Kotlin side has been
complete for a long time — JellyTauPlayer.load() parses a subtitles JSON
array into MediaItem.SubtitleConfigurations and setSubtitleTrack() drives a
TrackSelectionOverride — but nothing ever reached it.
VideoPlayer built the list and then threw it away: it resolved every
subtitle stream's URL into a subtitleTracks array and the
commands.playerPlayItem({...}) call two lines below passed only streamUrl,
title, id, videoCodec and needsTranscoding. PlayItemRequest had no subtitle
field to put them in, so create_media_item hardcoded subtitles: vec![],
android/mod.rs serialized "[]" across JNI, and every MediaItem reached
ExoPlayer with zero SubtitleConfigurations. A later set_subtitle_track then
found no text track groups and logged "Invalid subtitle track index".
PlayItemRequest now carries the tracks (defaulted, so the background-audio
handoff and next-episode callers are unchanged) and create_media_item
threads them onto the MediaItem.
Serialization: SubtitleTrack is reused verbatim rather than given an
IPC-specific twin, and deliberately keeps snake_case. The same struct feeds
two consumers that both spell mime_type — the JNI JSON that
JellyTauPlayer.load() reads with optString("mime_type"), and the generated
binding the frontend types against. camelCasing it would not fail the build
or the IPC; Kotlin would silently fall back to its default MIME type for
every track. UT-146 asserts the exact serialized keys so a future
rename_all cannot pass unnoticed.
The index mapping was NOT already correct. setSubtitleTrack(n) indexes
ExoPlayer's filtered text track groups, i.e. the position of the sideloaded
configuration — but the menu passed its own {#each} row number, which counts
every subtitle *stream*, including ones whose URL failed to resolve and were
therefore never sideloaded. One failed URL and every track below it selected
the wrong subtitle. The position is now looked up in the exact array that
was sent (nativeSubtitleArrayIndex), and a stream that was never sent maps
to "off" rather than to a guessed position.
The resolution loop also reuses resolveSubtitleTracks() from the Linux fix
instead of duplicating it, which fans the URL requests out in parallel
rather than awaiting them one per stream before playback can start. The
awaits are safe where they sit: the native-mode pitfall is about Svelte
lifecycle calls after an await, and nothing is registered here — the
background-audio subscriptions above still run synchronously.
No Kotlin change was needed.
Tests (UT-145, UT-146, UT-147) were written first and failed: PlayItemRequest
had no subtitles field to compile against, nativeSubtitleTracks and
nativeSubtitleArrayIndex did not exist, and the playerPlayItem call carried
no subtitles key.
TRACES: UR-020 | IR-016, JA-008 | UT-145, UT-146, UT-147
Rust: PlayerMediaItem and MergedMediaItem gain image_id (dual-carry),
populated from primary_image_tag at every construction/conversion site.
Regenerated bindings.
Frontend: all catalog + player + merged readers now use imageId. The
NowPlayingItem->MediaItem bridge (player.ts) properly maps the remote
session's Jellyfin fields (Type, runTimeTicks, primaryImageTag) onto the
neutral kind/durationMs/imageId. Types that are genuinely out of scope
(Person, NowPlayingItem, PlayItemRequest) keep primaryImageTag.
Rust 456, frontend 644, check clean.
Hand video playback off to a native audio-only stream when the app is
backgrounded or locked, with no on-device video decode (UR-040). Adds
player_enter/exit_background_audio commands, an audio-only stream URL
for video items across the repository layer, and the frontend handoff
state machine wired into VideoPlayer. Includes accompanying
repository/offline/player refactoring and regenerates the traceability
matrix.
Casting: restore camelCase serialization on SessionInfo/NowPlayingItem/PlayState
(container rename_all = "camelCase" + per-field PascalCase serde aliases so Jellyfin
PascalCase still deserializes). Bindings and the existing frontend are camelCase
again — casting works with no frontend session changes.
Downloads: migrate DownloadButton.svelte and downloads.ts to the typed
commands.downloadItemAndStart / downloadItem / downloadVideo wrappers (request
objects), matching the bundled backend signatures.
Tooling:
- Enable tauri-specta ErrorHandlingMode::Throw so commands.* return Promise<T>
and throw (drop-in for invoke()).
- Disambiguate specta name collisions: player MediaItem/MediaSource ->
PlayerMediaItem/PlayerMediaSource, auth ServerInfo -> AuthServerInfo.
- Regenerate bindings.ts; svelte-check passes (0 errors).
- Add #[specta::specta] to all 201 #[tauri::command] functions.
- Derive specta::Type on all IPC DTOs (repository/types, settings, player/storage/
download command DTOs, player enums, jellyfin SessionInfo/NowPlayingItem/PlayState,
ThumbnailCacheStats, DownloadInfo, CacheConfig, etc.).
- Replace tauri::generate_handler! with a tauri_specta::Builder + collect_commands!
in lib.rs (exports bindings.ts in debug builds).
Two contract changes required by specta constraints (frontend migration follows):
- specta caps command arity at 10 args: download_item_and_start / download_item /
download_video now take a single request struct (params bundled, body unchanged
via destructuring).
- specta can't parse split serde rename_all: SessionInfo/NowPlayingItem/PlayState
switched to rename_all = "PascalCase" (Jellyfin deserialization preserved; these
now serialize PascalCase to the frontend).
cargo check --lib is clean (0 errors). Frontend migration to bindings.ts is the next step.
dtourolle
