fix(player): 修复详情往返播放位置丢失

lib/app.dart

@@ -42,6 +42,7 @@ import 'core/data/services/favorite_controller.dart';
 import 'core/data/services/interaction_controller.dart';
 import 'core/data/services/locale_controller.dart';
 import 'core/data/services/event_tracker.dart';
+import 'core/data/services/playback_position_cache.dart';
 import 'core/data/services/playback_session.dart';
 import 'core/data/services/video_player_port.dart';
 import 'core/data/services/wallet_controller.dart';
@@ -72,6 +73,7 @@ class LumaDramaApp extends StatefulWidget {
     this.watchHistoryRepository,
     this.favoriteRepository,
     this.playbackRepository,
+    this.playbackPositionCache,
     this.commentRepository,
     this.interactionRepository,
     this.noticeRepository,
@@ -91,6 +93,7 @@ class LumaDramaApp extends StatefulWidget {
   final WatchHistoryRepository? watchHistoryRepository;
   final FavoriteRepository? favoriteRepository;
   final PlaybackRepository? playbackRepository;
+  final PlaybackPositionCache? playbackPositionCache;
   final CommentRepository? commentRepository;
   final InteractionRepository? interactionRepository;
   final NoticeRepository? noticeRepository;
@@ -146,6 +149,9 @@ class _LumaDramaAppState extends State<LumaDramaApp> {
       widget.playbackRepository ??
       HttpPlaybackRepository(PlaybackApi(_apiClient));
 
+  late final PlaybackPositionCache _playbackPositionCache =
+      widget.playbackPositionCache ?? PlaybackPositionCache();
+
   late final FavoriteController _favoriteController = FavoriteController(
     _favorites,
   );
@@ -240,6 +246,7 @@ class _LumaDramaAppState extends State<LumaDramaApp> {
         Provider<PlayerFactory>(create: (_) => widget.playerFactory),
         Provider<CatalogRepository>.value(value: _catalogRepository),
         Provider<PlaybackRepository>.value(value: _playback),
+        Provider<PlaybackPositionCache>.value(value: _playbackPositionCache),
         Provider<WatchHistoryRepository>.value(value: _watchHistory),
         Provider<FavoriteRepository>.value(value: _favorites),
         Provider<CommentRepository>.value(value: _commentRepository),

lib/core/data/services/playback_position_cache.dart

@@ -0,0 +1,79 @@
+// Author: fruit.com.cn
+
+const Duration _defaultMaxAge = Duration(hours: 12);
+
+/// 进程内最近播放位置。
+class CachedPlaybackPosition {
+  const CachedPlaybackPosition({
+    required this.episodeId,
+    required this.dramaId,
+    required this.position,
+    required this.duration,
+    required this.updatedAt,
+  });
+
+  final String episodeId;
+  final String dramaId;
+  final Duration position;
+  final Duration duration;
+  final DateTime updatedAt;
+}
+
+/// 按集缓存最近播放位置，仅当前进程有效。
+class PlaybackPositionCache {
+  PlaybackPositionCache({
+    DateTime Function()? now,
+    this.maxAge = _defaultMaxAge,
+  }) : _now = now ?? DateTime.now;
+
+  final DateTime Function() _now;
+  final Duration maxAge;
+  final Map<String, CachedPlaybackPosition> _positions = {};
+
+  /// 保存最近有效播放位置；零位置不会覆盖已有记录。
+  void save({
+    required String episodeId,
+    required String dramaId,
+    required Duration position,
+    required Duration duration,
+  }) {
+    if (episodeId.isEmpty || dramaId.isEmpty || position <= Duration.zero) {
+      return;
+    }
+    _positions[episodeId] = CachedPlaybackPosition(
+      episodeId: episodeId,
+      dramaId: dramaId,
+      position: position,
+      duration: duration,
+      updatedAt: _now(),
+    );
+  }
+
+  /// 读取同剧同集且未过期的最近位置。
+  CachedPlaybackPosition? read(String episodeId, {required String dramaId}) {
+    final entry = _positions[episodeId];
+    if (!_isValid(entry, dramaId)) return null;
+    return entry;
+  }
+
+  /// 读取指定短剧最近更新的有效位置。
+  CachedPlaybackPosition? latestForDrama(String dramaId) {
+    CachedPlaybackPosition? latest;
+    for (final entry in _positions.values) {
+      if (!_isValid(entry, dramaId)) continue;
+      if (latest == null || !entry.updatedAt.isBefore(latest.updatedAt)) {
+        latest = entry;
+      }
+    }
+    return latest;
+  }
+
+  bool _isValid(CachedPlaybackPosition? entry, String dramaId) {
+    if (entry == null ||
+        entry.dramaId != dramaId ||
+        entry.position <= Duration.zero) {
+      return false;
+    }
+    return _now().difference(entry.updatedAt) <= maxAge;
+  }
+}

lib/pages/drama_detail/drama_detail_binding.dart

@@ -4,6 +4,7 @@ import '../../core/data/models/drama.dart';
 import '../../core/data/repositories/playback_repository.dart';
 import '../../core/data/repositories/watch_history_repository.dart';
 import '../../core/data/services/favorite_controller.dart';
+import '../../core/data/services/playback_position_cache.dart';
 import 'drama_detail_logic.dart';
 
 class DramaDetailBinding {
@@ -12,10 +13,12 @@ class DramaDetailBinding {
     required WatchHistoryRepository history,
     required PlaybackRepository playback,
     required FavoriteController favorites,
+    required PlaybackPositionCache positionCache,
   }) => DramaDetailLogic(
     drama: drama,
     history: history,
     playback: playback,
     favorites: favorites,
+    positionCache: positionCache,
   );
 }

lib/pages/drama_detail/drama_detail_logic.dart

@@ -11,6 +11,7 @@ import '../../core/data/repositories/watch_history_repository.dart';
 import '../../core/data/repositories/playback_repository.dart';
 import '../../core/data/services/favorite_controller.dart';
 import '../../core/data/services/download_controller.dart';
+import '../../core/data/services/playback_position_cache.dart';
 import '../../core/data/services/wallet_controller.dart';
 import '../player/player_view.dart';
 
@@ -20,6 +21,7 @@ class DramaDetailLogic extends ChangeNotifier {
     required this.history,
     required this.playback,
     required this.favorites,
+    required this.positionCache,
   });
 
   /// 先用列表卡片渲染，取到详情后换成带完整剧集的版本。
@@ -27,6 +29,7 @@ class DramaDetailLogic extends ChangeNotifier {
   final WatchHistoryRepository history;
   final PlaybackRepository playback;
   final FavoriteController favorites;
+  final PlaybackPositionCache positionCache;
   bool loading = false;
   bool failed = false;
 
@@ -71,6 +74,23 @@ class DramaDetailLogic extends ChangeNotifier {
   }
 
   Future<void> loadContinue() async {
+    final cached = positionCache.latestForDrama(drama.id);
+    if (cached != null) {
+      final index = _indexOf(cached.episodeId);
+      if (index != null) {
+        progress = WatchProgress(
+          dramaId: cached.dramaId,
+          episodeId: cached.episodeId,
+          position: cached.position,
+          duration: cached.duration,
+          updatedAt: cached.updatedAt,
+        );
+        continueIndex = index;
+        progressError = null;
+        notify();
+        return;
+      }
+    }
     try {
       final record = await history.progressFor(drama.id);
       if (_disposed) return;

lib/pages/drama_detail/drama_detail_view.dart

@@ -12,6 +12,7 @@ import '../../core/data/repositories/watch_history_repository.dart';
 import '../../core/data/services/catalog_controller.dart';
 import '../../core/data/services/favorite_controller.dart';
 import '../../core/data/services/interaction_controller.dart';
+import '../../core/data/services/playback_position_cache.dart';
 import '../../core/data/services/platform_share_service.dart';
 import '../../core/formatting/error_text.dart';
 import '../../core/formatting/localized_content.dart';
@@ -64,6 +65,7 @@ class _DramaDetailPageState extends State<DramaDetailPage> {
       history: context.read<WatchHistoryRepository>(),
       playback: context.read<PlaybackRepository>(),
       favorites: context.read<FavoriteController>(),
+      positionCache: context.read<PlaybackPositionCache>(),
     );
     _load();
   }

lib/pages/player/player_binding.dart

@@ -4,6 +4,7 @@ import '../../core/data/repositories/watch_history_repository.dart';
 import '../../core/data/repositories/playback_repository.dart';
 import '../../core/data/services/android_picture_in_picture.dart';
 import '../../core/data/services/download_controller.dart';
+import '../../core/data/services/playback_position_cache.dart';
 import '../../core/data/services/wallet_controller.dart';
 import 'player_logic.dart';
 
@@ -11,11 +12,13 @@ class PlayerBinding {
   PlayerLogic create({
     required WatchHistoryRepository history,
     required PlaybackRepository playback,
+    required PlaybackPositionCache positionCache,
     WalletController? wallet,
     DownloadController? downloads,
   }) => PlayerLogic(
     history: history,
     playback: playback,
+    positionCache: positionCache,
     pictureInPicture: AndroidPictureInPicture(),
     wallet: wallet,
     downloads: downloads,

lib/pages/player/player_logic.dart

@@ -17,6 +17,7 @@ import '../../core/data/services/android_picture_in_picture.dart';
 import '../../core/data/services/catalog_controller.dart';
 import '../../core/data/services/download_controller.dart';
 import '../../core/data/services/platform_share_service.dart';
+import '../../core/data/services/playback_position_cache.dart';
 import '../../core/data/services/playback_queue.dart';
 import '../../core/data/services/playback_session.dart';
 import '../../core/data/services/video_player_port.dart';
@@ -40,8 +41,10 @@ class PlayerLogic extends ChangeNotifier {
     required this.pictureInPicture,
     this.wallet,
     this.downloads,
+    PlaybackPositionCache? positionCache,
     Future<void> Function()? waitForFrame,
-  }) : _waitForFrame =
+  }) : positionCache = positionCache ?? PlaybackPositionCache(),
+       _waitForFrame =
            waitForFrame ?? (() => WidgetsBinding.instance.endOfFrame);
 
   final WatchHistoryRepository history;
@@ -49,6 +52,7 @@ class PlayerLogic extends ChangeNotifier {
   final AndroidPictureInPicture pictureInPicture;
   final WalletController? wallet;
   final DownloadController? downloads;
+  final PlaybackPositionCache positionCache;
   final Future<void> Function() _waitForFrame;
 
   late PageController pages;
@@ -351,9 +355,22 @@ class PlayerLogic extends ChangeNotifier {
 
   /// 服务端续看位置：进播放页时取一次，用于"定位到上次那一集的那一秒"。
   Future<void> loadResumePoint() async {
-    final dramaId = queue.entryAt(initialIndex).drama.id;
+    final entry = queue.entryAt(initialIndex);
+    final cached = positionCache.read(
+      entry.episode.id,
+      dramaId: entry.drama.id,
+    );
+    if (cached != null) {
+      resumePoint = ResumePoint(
+        episodeId: cached.episodeId,
+        position: cached.position,
+      );
+      resumeLoaded = true;
+      if (isMounted()) notify();
+      return;
+    }
     try {
-      resumePoint = await history.resumePointFor(dramaId);
+      resumePoint = await history.resumePointFor(entry.drama.id);
     } catch (_) {
       // 拿不到续看位置不影响播放：从当前集开头看
       resumePoint = null;
@@ -639,6 +656,18 @@ class PlayerLogic extends ChangeNotifier {
       await pendingWrite;
       // 服务端每剧只记一条：只有"记录里的那一集"才定位，其它集从头播
       if (resumePoint == null) await loadResumePoint();
+      if (resumePositionFor(episode.id) == null) {
+        final dramaId = _dramaIdForEpisode(episode.id);
+        final cached = dramaId == null
+            ? null
+            : positionCache.read(episode.id, dramaId: dramaId);
+        if (cached != null) {
+          resumePoint = ResumePoint(
+            episodeId: cached.episodeId,
+            position: cached.position,
+          );
+        }
+      }
       final saved = resumePositionFor(episode.id);
       if (saved != null) {
         await player.controller.seekTo(
@@ -667,6 +696,12 @@ class PlayerLogic extends ChangeNotifier {
       if (session.active != player || !player.controller.value.isInitialized) {
         return;
       }
+      positionCache.save(
+        episodeId: episode.id,
+        dramaId: drama.id,
+        position: player.controller.value.position,
+        duration: player.controller.value.duration,
+      );
       if (player.controller.value.isCompleted && !completionProgressSaved) {
         completionProgressSaved = true;
         unawaited(
@@ -750,6 +785,12 @@ class PlayerLogic extends ChangeNotifier {
         !player.controller.value.isInitialized) {
       return pendingWrite;
     }
+    positionCache.save(
+      episodeId: episode.id,
+      dramaId: drama.id,
+      position: player.controller.value.position,
+      duration: player.controller.value.duration,
+    );
     return queueProgress(
       drama,
       episode,
@@ -851,6 +892,7 @@ class PlayerLogic extends ChangeNotifier {
 
   Future<void> openDetail(BuildContext context) async {
     session.setOverlayOpen(true);
+    await saveCurrentProgress();
     try {
       if (!context.mounted) return;
       await Navigator.of(context).push(
@@ -865,6 +907,13 @@ class PlayerLogic extends ChangeNotifier {
     await saveCurrentProgress();
   }
 
+  String? _dramaIdForEpisode(String episodeId) {
+    for (final entry in queue.entries) {
+      if (entry.episode.id == episodeId) return entry.drama.id;
+    }
+    return null;
+  }
+
   Future<void> openSeriesAt(
     BuildContext context,
     Drama drama,

lib/pages/player/player_view.dart

@@ -11,6 +11,7 @@ import '../../core/data/repositories/comment_repository.dart';
 import '../../core/data/services/favorite_controller.dart';
 import '../../core/data/services/download_controller.dart';
 import '../../core/data/services/interaction_controller.dart';
+import '../../core/data/services/playback_position_cache.dart';
 import '../../core/data/services/playback_session.dart';
 import '../../core/data/services/video_player_port.dart';
 import '../../core/data/services/wallet_controller.dart';
@@ -119,6 +120,7 @@ class _PlayerPageState extends State<PlayerPage>
     logic = PlayerBinding().create(
       history: context.read<WatchHistoryRepository>(),
       playback: context.read<PlaybackRepository>(),
+      positionCache: context.read<PlaybackPositionCache>(),
       wallet: widget.wallet,
       downloads: widget.downloads,
     );