fix(player): stop writing show-wide track defaults

lib/screens/video_player_screen.dart

@@ -168,37 +168,24 @@ _PlaybackOpenTiming _playbackOpenTiming({
   );
 }
 
-/// Builds a [TrackPreferencePersister] that fans the language-preference +
-/// stream-selection writes out to a [PlexClient] resolved lazily on each
-/// call. Returns a no-op-on-null persister so the [TrackManager] doesn't
-/// have to import [PlexClient] itself; the resolver returning null (e.g.
-/// when the active server is Jellyfin) makes the call short-circuit.
+/// Builds a [TrackPreferencePersister] that writes the per-episode stream
+/// selection out to a [PlexClient] resolved lazily on each call. Returns a
+/// no-op-on-null persister so the [TrackManager] doesn't have to import
+/// [PlexClient] itself; the resolver returning null (e.g. when the active
+/// server is Jellyfin) makes the call short-circuit.
+///
+/// Only the current episode's part is touched — we deliberately do NOT write
+/// the show-wide audio/subtitle language default (#1393): an in-player track
+/// change should not silently rewrite the whole series' Plex prefs. The
+/// explicit path for that lives in the metadata-edit UI.
 TrackPreferencePersister _plexTrackPersister(PlexClient? Function() resolve) {
-  return ({
-    required String id,
-    required int partId,
-    required String trackType,
-    String? languageCode,
-    int? streamID,
-  }) async {
+  return ({required int partId, required String trackType, int? streamID}) async {
+    if (streamID == null) return;
     final client = resolve();
     if (client == null) return;
-    final futures = <Future>[];
-    if (languageCode != null && (trackType == 'subtitle' || languageCode.isNotEmpty)) {
-      futures.add(
-        trackType == 'audio'
-            ? client.setMetadataPreferences(id, audioLanguage: languageCode)
-            : client.setMetadataPreferences(id, subtitleLanguage: languageCode),
-      );
-    }
-    if (streamID != null) {
-      futures.add(
-        trackType == 'audio'
-            ? client.selectStreams(partId, audioStreamID: streamID, allParts: true)
-            : client.selectStreams(partId, subtitleStreamID: streamID, allParts: true),
-      );
-    }
-    await Future.wait(futures);
+    await (trackType == 'audio'
+        ? client.selectStreams(partId, audioStreamID: streamID, allParts: true)
+        : client.selectStreams(partId, subtitleStreamID: streamID, allParts: true));
   };
 }
 

lib/services/plex_client.dart

@@ -1198,29 +1198,6 @@ class PlexClient
     );
   }
 
-  /// Set per-media language preferences (audio and subtitle)
-  /// For TV shows, use grandparentRatingKey to set preference for the entire series
-  /// For movies, use the movie's ratingKey
-  Future<bool> setMetadataPreferences(String ratingKey, {String? audioLanguage, String? subtitleLanguage}) async {
-    final queryParams = <String, dynamic>{};
-    if (audioLanguage != null) {
-      queryParams['audioLanguage'] = audioLanguage;
-    }
-    if (subtitleLanguage != null) {
-      queryParams['subtitleLanguage'] = subtitleLanguage;
-    }
-
-    // If no preferences to set, return early
-    if (queryParams.isEmpty) {
-      return true;
-    }
-
-    return _wrapBoolApiCall(
-      () => _http.put('/library/metadata/$ratingKey/prefs', queryParameters: queryParams),
-      'Failed to set metadata preferences',
-    );
-  }
-
   /// Select specific audio and subtitle streams for playback
   /// This updates which streams are "selected" in the media metadata
   /// Uses the part ID from media info for accurate stream selection

lib/services/track_manager.dart

@@ -3,7 +3,6 @@ import 'dart:async';
 import '../mpv/mpv.dart';
 
 import '../media/media_item.dart';
-import '../media/media_item_types.dart';
 import '../media/media_server_user_profile.dart';
 import '../media/media_source_info.dart';
 import '../services/settings_service.dart';
@@ -12,16 +11,14 @@ import '../utils/app_logger.dart';
 import '../utils/language_codes.dart';
 import '../utils/track_label_builder.dart';
 
-/// Persists a track choice through Plex's immediate preference endpoints.
+/// Persists a track choice for the current part to the server.
 /// Backends that persist through another path (Jellyfin uses playback progress
-/// stream indexes) or lack server-side track preferences leave this null.
+/// stream indexes) or lack server-side stream selection leave this null.
 /// [trackType] is `'audio'` or `'subtitle'`.
 typedef TrackPreferencePersister =
     Future<void> Function({
-      required String id,
       required int partId,
       required String trackType,
-      String? languageCode,
       int? streamID,
     });
 
@@ -342,7 +339,7 @@ class TrackManager {
       }
     }
 
-    await _saveTrackPreferences(partId: partId, trackType: 'audio', languageCode: track.language, streamID: streamID);
+    await _saveTrackPreferences(partId: partId, trackType: 'audio', streamID: streamID);
   }
 
   /// Handle subtitle track changes — save stream selection and language preference.
@@ -351,16 +348,12 @@ class TrackManager {
     final partId = await _guardTrackChange(info);
     if (partId == null) return;
 
-    String? languageCode;
     int? streamID;
 
     if (track.id == 'no') {
-      languageCode = 'none';
       streamID = 0;
       appLogger.i('User turned subtitles off, saving preference');
     } else if (info != null) {
-      languageCode = track.language;
-
       streamID = _matchTrackByAttributes(
         mpvLanguage: track.language,
         mpvTitle: track.title,
@@ -388,7 +381,7 @@ class TrackManager {
       }
     }
 
-    await _saveTrackPreferences(partId: partId, trackType: 'subtitle', languageCode: languageCode, streamID: streamID);
+    await _saveTrackPreferences(partId: partId, trackType: 'subtitle', streamID: streamID);
   }
 
   /// Handle secondary subtitle track changes — no server save needed.
@@ -399,11 +392,6 @@ class TrackManager {
 
   // ── Private helpers ────────────────────────────────────────────────
 
-  /// Series/movie-level identifier used for language preferences.
-  String get _preferenceId {
-    return metadata.isEpisode ? (metadata.grandparentId ?? metadata.id) : metadata.id;
-  }
-
   /// Common guard checks for track change handlers.
   Future<int?> _guardTrackChange(MediaSourceInfo? info) async {
     final settings = await SettingsService.getInstance();
@@ -423,29 +411,18 @@ class TrackManager {
     return partId;
   }
 
-  /// Save language preference and stream selection to the server.
-  Future<void> _saveTrackPreferences({
-    required int partId,
-    required String trackType,
-    String? languageCode,
-    int? streamID,
-  }) async {
+  /// Save the stream selection for the current part to the server.
+  Future<void> _saveTrackPreferences({required int partId, required String trackType, int? streamID}) async {
     try {
       if (!isActive()) return;
       final persist = persistTrackPreference;
       if (persist == null) {
         return;
       }
-      await persist(
-        id: _preferenceId,
-        partId: partId,
-        trackType: trackType,
-        languageCode: languageCode,
-        streamID: streamID,
-      );
-      appLogger.d('Successfully saved $trackType preferences (language + stream)');
+      await persist(partId: partId, trackType: trackType, streamID: streamID);
+      appLogger.d('Successfully saved $trackType stream selection');
     } catch (e) {
-      appLogger.e('Failed to save $trackType preferences', error: e);
+      appLogger.e('Failed to save $trackType stream selection', error: e);
     }
   }
 

test/services/track_manager_test.dart

@@ -144,13 +144,7 @@ Future<void> _drainAsync() async {
   }
 }
 
-Future<void> _noopPersister({
-  required String id,
-  required int partId,
-  required String trackType,
-  String? languageCode,
-  int? streamID,
-}) async {}
+Future<void> _noopPersister({required int partId, required String trackType, int? streamID}) async {}
 
 void main() {
   // The constructor doesn't touch prefs, but [dispose] / [applyTrackSelection]