fix(player): 修复详情往返播放位置丢失

test/drama_detail/drama_detail_first_frame_test.dart

@@ -14,6 +14,7 @@ import 'package:fruitshorts/core/data/repositories/playback_repository.dart';
 import 'package:fruitshorts/core/data/repositories/watch_history_repository.dart';
 import 'package:fruitshorts/core/data/services/catalog_controller.dart';
 import 'package:fruitshorts/core/data/services/favorite_controller.dart';
+import 'package:fruitshorts/core/data/services/playback_position_cache.dart';
 import 'package:fruitshorts/l10n/app_localizations.dart';
 import 'package:fruitshorts/pages/drama_detail/drama_detail_view.dart';
 
@@ -102,6 +103,7 @@ Future<void> _pumpDetail(
           value: InMemoryWatchHistoryRepository(),
         ),
         Provider<PlaybackRepository>.value(value: FakePlaybackRepository()),
+        Provider<PlaybackPositionCache>(create: (_) => PlaybackPositionCache()),
         ChangeNotifierProvider<FavoriteController>.value(value: favorites),
         ChangeNotifierProvider(
           create: (_) => CatalogController(catalog)..load(),

test/drama_detail/drama_detail_logic_test.dart

@@ -1,9 +1,11 @@
 import 'package:flutter_test/flutter_test.dart';
 import 'package:fruitshorts/core/data/models/drama.dart';
+import 'package:fruitshorts/core/data/models/watch_progress.dart';
 import 'package:fruitshorts/core/data/remote/api_client.dart';
 import 'package:fruitshorts/core/data/repositories/favorite_repository.dart';
 import 'package:fruitshorts/core/data/repositories/playback_repository.dart';
 import 'package:fruitshorts/core/data/services/favorite_controller.dart';
+import 'package:fruitshorts/core/data/services/playback_position_cache.dart';
 import 'package:fruitshorts/pages/drama_detail/drama_detail_logic.dart';
 
 import '../support/fake_watch_history.dart';
@@ -13,12 +15,14 @@ DramaDetailLogic _logic(
   Drama drama,
   FakeWatchHistory history, {
   FavoriteController? favorites,
+  PlaybackPositionCache? positionCache,
 }) =>
     DramaDetailLogic(
       drama: drama,
       history: history,
       playback: FakePlaybackRepository(),
       favorites: favorites ?? FavoriteController(InMemoryFavoriteRepository()),
+      positionCache: positionCache ?? PlaybackPositionCache(),
     );
 
 Drama _card(String id) => Drama(
@@ -103,6 +107,31 @@ void main() {
     logic.dispose();
   });
 
+  test('should_prefer_recent_local_position_when_loading_continue', () async {
+    final cache = PlaybackPositionCache();
+    cache.save(
+      episodeId: 'signal-3',
+      dramaId: 'signal',
+      position: const Duration(minutes: 1, seconds: 20),
+      duration: const Duration(minutes: 3),
+    );
+    final history = FakeWatchHistory()
+      ..records['signal'] = const WatchProgress(
+        dramaId: 'signal',
+        episodeId: 'signal-1',
+        position: Duration(seconds: 5),
+        duration: Duration(minutes: 3),
+      );
+    final logic = _logic(_detail('signal'), history, positionCache: cache);
+
+    await logic.load(() async => _detail('signal'));
+
+    expect(logic.continueIndex, 2);
+    expect(logic.progress?.position, const Duration(seconds: 80));
+    expect(history.reads, isEmpty);
+    logic.dispose();
+  });
+
   test('should_adjust_favorite_count_only_after_successful_changes', () async {
     final repository = InMemoryFavoriteRepository(cards: [_favoriteDrama]);
     final favorites = FavoriteController(repository);

test/drama_detail/drama_detail_view_test.dart

@@ -27,6 +27,7 @@ import 'package:fruitshorts/core/data/services/auth_session_store.dart';
 import 'package:fruitshorts/core/data/services/catalog_controller.dart';
 import 'package:fruitshorts/core/data/services/download_controller.dart';
 import 'package:fruitshorts/core/data/services/favorite_controller.dart';
+import 'package:fruitshorts/core/data/services/playback_position_cache.dart';
 import 'package:fruitshorts/core/data/services/interaction_controller.dart';
 import 'package:fruitshorts/core/data/services/playback_session.dart';
 import 'package:fruitshorts/core/data/services/wallet_controller.dart';
@@ -259,6 +260,25 @@ void main() {
     expect(player.initialIndex, 79);
   });
 
+  testWidgets('should_open_recent_cached_episode_when_detail_cta_is_tapped', (
+    tester,
+  ) async {
+    final cache = PlaybackPositionCache();
+    cache.save(
+      episodeId: 'detail-k38-3',
+      dramaId: 'detail-k38',
+      position: const Duration(minutes: 1, seconds: 20),
+      duration: const Duration(minutes: 3),
+    );
+    await _pumpDetail(tester, positionCache: cache);
+
+    await tester.tap(find.byKey(const Key('detail-cta')));
+    await tester.pumpAndSettle();
+
+    final player = tester.widget<PlayerPage>(find.byType(PlayerPage));
+    expect(player.initialIndex, 2);
+  });
+
   testWidgets('should_fit_compact_viewport_and_keep_cta_visible', (
     tester,
   ) async {
@@ -283,6 +303,7 @@ Future<void> _pumpDetail(
   WidgetTester tester, {
   Drama? drama,
   Size size = const Size(390, 844),
+  PlaybackPositionCache? positionCache,
 }) async {
   tester.view.physicalSize = size;
   tester.view.devicePixelRatio = 1;
@@ -303,6 +324,9 @@ Future<void> _pumpDetail(
           value: InMemoryWatchHistoryRepository(),
         ),
         Provider<PlaybackRepository>.value(value: FakePlaybackRepository()),
+        Provider<PlaybackPositionCache>.value(
+          value: positionCache ?? PlaybackPositionCache(),
+        ),
         Provider<PlayerFactory>.value(value: createWidgetPlayer),
         Provider(create: (_) => PlaybackCoordinator()),
         Provider<InteractionRepository>.value(value: interactions),

test/playback/playback_position_cache_test.dart

@@ -0,0 +1,69 @@
+// Author: fruit.com.cn
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:fruitshorts/core/data/services/playback_position_cache.dart';
+
+void main() {
+  test('should_store_and_read_recent_position_when_drama_matches', () {
+    final now = DateTime(2026, 10, 22, 12);
+    final cache = PlaybackPositionCache(now: () => now);
+
+    cache.save(
+      episodeId: 'episode-3',
+      dramaId: 'drama-a',
+      position: const Duration(minutes: 1, seconds: 20),
+      duration: const Duration(minutes: 3),
+    );
+
+    final entry = cache.read('episode-3', dramaId: 'drama-a');
+    expect(entry, isNotNull);
+    expect(entry!.position, const Duration(minutes: 1, seconds: 20));
+    expect(entry.duration, const Duration(minutes: 3));
+    expect(entry.updatedAt, now);
+  });
+
+  test('should_reject_cached_position_when_drama_does_not_match', () {
+    final cache = PlaybackPositionCache();
+    cache.save(
+      episodeId: 'episode-3',
+      dramaId: 'drama-a',
+      position: const Duration(seconds: 80),
+      duration: const Duration(minutes: 3),
+    );
+
+    expect(cache.read('episode-3', dramaId: 'drama-b'), isNull);
+  });
+
+  test('should_use_latest_saved_episode_when_timestamps_match', () {
+    final now = DateTime(2026, 10, 22, 12);
+    final cache = PlaybackPositionCache(now: () => now);
+    cache.save(
+      episodeId: 'episode-1',
+      dramaId: 'drama-a',
+      position: const Duration(seconds: 30),
+      duration: const Duration(minutes: 3),
+    );
+    cache.save(
+      episodeId: 'episode-2',
+      dramaId: 'drama-a',
+      position: const Duration(seconds: 45),
+      duration: const Duration(minutes: 3),
+    );
+
+    expect(cache.latestForDrama('drama-a')?.episodeId, 'episode-2');
+  });
+
+  test('should_reject_expired_cached_position', () {
+    var now = DateTime(2026, 10, 22, 12);
+    final cache = PlaybackPositionCache(now: () => now);
+    cache.save(
+      episodeId: 'episode-3',
+      dramaId: 'drama-a',
+      position: const Duration(seconds: 80),
+      duration: const Duration(minutes: 3),
+    );
+    now = now.add(const Duration(days: 1));
+
+    expect(cache.read('episode-3', dramaId: 'drama-a'), isNull);
+  });
+}

test/player/player_logic_test.dart

@@ -5,6 +5,7 @@ import 'package:video_player/video_player.dart';
 import 'package:fruitshorts/core/data/models/drama.dart';
 import 'package:fruitshorts/core/data/models/play_ticket.dart';
 import 'package:fruitshorts/core/data/models/player_port.dart';
+import 'package:fruitshorts/core/data/models/watch_progress.dart';
 import 'package:fruitshorts/core/data/models/download_license.dart';
 import 'package:fruitshorts/core/data/models/download_policy.dart';
 import 'package:fruitshorts/core/data/repositories/download_repository.dart';
@@ -12,6 +13,7 @@ import 'package:fruitshorts/core/data/services/android_picture_in_picture.dart';
 import 'package:fruitshorts/core/data/services/download_controller.dart';
 import 'package:fruitshorts/core/data/services/download_storage.dart';
 import 'package:fruitshorts/core/data/services/playback_session.dart';
+import 'package:fruitshorts/core/data/services/playback_position_cache.dart';
 import 'package:fruitshorts/core/data/services/video_player_port.dart';
 import 'package:fruitshorts/pages/player/player_logic.dart';
 import 'package:fruitshorts/pages/player/player_view.dart';
@@ -48,11 +50,13 @@ AndroidPictureInPicture _pip() =>
 PlayerLogic _logic(
   FakeWatchHistory history, {
   PlaybackRepository? playback,
+  PlaybackPositionCache? positionCache,
   Future<void> Function()? waitForFrame,
 }) => PlayerLogic(
   history: history,
   playback: playback ?? FakePlaybackRepository(),
   pictureInPicture: _pip(),
+  positionCache: positionCache,
   waitForFrame: waitForFrame ?? () async {},
 );
 
@@ -126,6 +130,96 @@ void main() {
     });
   });
 
+  group('playback position cache', () {
+    test('should_use_cached_resume_point_without_reading_history', () async {
+      final history = FakeWatchHistory()..saved = const Duration(seconds: 12);
+      final cache = PlaybackPositionCache();
+      cache.save(
+        episodeId: 'signal-1',
+        dramaId: 'signal',
+        position: const Duration(minutes: 1, seconds: 20),
+        duration: const Duration(minutes: 3),
+      );
+      final logic = _logic(history, positionCache: cache);
+      logic.attach(
+        PlayerPage(drama: _drama('signal'), initialIndex: 0, active: false),
+        isMounted: () => true,
+      );
+      logic.start(
+        factory: _RecordingFactory().create,
+        coordinator: PlaybackCoordinator(),
+      );
+      await _drain(logic);
+      await pumpEventQueue();
+
+      expect(logic.resumePoint?.position, const Duration(seconds: 80));
+      expect(history.reads, isEmpty);
+      logic.dispose();
+      await _drain(logic);
+    });
+
+    test('should_fall_back_to_server_when_cache_belongs_to_other_drama',
+        () async {
+      final history = FakeWatchHistory()
+        ..records['signal'] = const WatchProgress(
+          dramaId: 'signal',
+          episodeId: 'signal-2',
+          position: Duration(seconds: 42),
+          duration: Duration(minutes: 3),
+        );
+      final cache = PlaybackPositionCache();
+      cache.save(
+        episodeId: 'signal-1',
+        dramaId: 'other-drama',
+        position: const Duration(seconds: 80),
+        duration: const Duration(minutes: 3),
+      );
+      final logic = _logic(history, positionCache: cache);
+      logic.attach(
+        PlayerPage(drama: _drama('signal'), initialIndex: 0, active: false),
+        isMounted: () => true,
+      );
+      logic.start(
+        factory: _RecordingFactory().create,
+        coordinator: PlaybackCoordinator(),
+      );
+      await _drain(logic);
+      await pumpEventQueue();
+
+      expect(logic.resumePoint?.episodeId, 'signal-2');
+      expect(logic.resumePoint?.position, const Duration(seconds: 42));
+      expect(history.reads, ['signal']);
+      logic.dispose();
+      await _drain(logic);
+    });
+
+    test('should_fall_back_to_server_when_cache_is_missing', () async {
+      final history = FakeWatchHistory()
+        ..records['signal'] = const WatchProgress(
+          dramaId: 'signal',
+          episodeId: 'signal-1',
+          position: Duration(seconds: 36),
+          duration: Duration(minutes: 3),
+        );
+      final logic = _logic(history);
+      logic.attach(
+        PlayerPage(drama: _drama('signal'), initialIndex: 0, active: false),
+        isMounted: () => true,
+      );
+      logic.start(
+        factory: _RecordingFactory().create,
+        coordinator: PlaybackCoordinator(),
+      );
+      await _drain(logic);
+      await pumpEventQueue();
+
+      expect(logic.resumePoint?.position, const Duration(seconds: 36));
+      expect(history.reads, ['signal']);
+      logic.dispose();
+      await _drain(logic);
+    });
+  });
+
   test('should_play_local_file_without_ticket_when_episode_is_downloaded',
       () async {
     final playback = FakePlaybackRepository();

test/player/player_open_detail_test.dart

@@ -13,6 +13,7 @@ import 'package:fruitshorts/core/data/repositories/watch_history_repository.dart
 import 'package:fruitshorts/core/data/services/android_picture_in_picture.dart';
 import 'package:fruitshorts/core/data/services/catalog_controller.dart';
 import 'package:fruitshorts/core/data/services/favorite_controller.dart';
+import 'package:fruitshorts/core/data/services/playback_position_cache.dart';
 import 'package:fruitshorts/core/data/services/playback_session.dart';
 import 'package:fruitshorts/core/data/services/video_player_port.dart';
 import 'package:fruitshorts/core/platform/haptics.dart';
@@ -35,12 +36,14 @@ void main() {
       final history = FakeWatchHistory();
       final playback = FakePlaybackRepository();
       final catalog = CatalogController(FakeCatalogRepository(dramas: [drama]));
+      final positionCache = PlaybackPositionCache();
       final favorites = FavoriteController(
         InMemoryFavoriteRepository(saved: {drama.id}, cards: [drama]),
       );
       final logic = PlayerLogic(
         history: history,
         playback: playback,
+        positionCache: positionCache,
         pictureInPicture: AndroidPictureInPicture(
           channel: const MethodChannel('test/player_open_detail/pip'),
         ),
@@ -74,6 +77,7 @@ void main() {
           providers: [
             Provider<WatchHistoryRepository>.value(value: history),
             Provider<PlaybackRepository>.value(value: playback),
+            Provider<PlaybackPositionCache>.value(value: positionCache),
             ChangeNotifierProvider<CatalogController>.value(value: catalog),
             ChangeNotifierProvider<FavoriteController>.value(value: favorites),
             Provider<Haptics>.value(value: FakeHaptics()),
@@ -104,7 +108,11 @@ void main() {
       expect(player.pauses, 1);
       expect(player.plays, playsBefore);
       expect(tracked.controller.value.position, const Duration(seconds: 37));
-      expect(history.writes, isEmpty);
+      expect(history.writes, ['signal-1|37000|false']);
+      expect(
+        positionCache.read('signal-1', dramaId: 'signal')?.position,
+        const Duration(seconds: 37),
+      );
 
       await tester.pageBack();
       await tester.pump();
@@ -117,7 +125,10 @@ void main() {
       expect(logic.session.userWantsPlay, isTrue);
       expect(player.plays, playsBefore + 1);
       expect(tracked.controller.value.position, const Duration(seconds: 37));
-      expect(history.writes, ['signal-1|37000|false']);
+      expect(history.writes, [
+        'signal-1|37000|false',
+        'signal-1|37000|false',
+      ]);
 
       logic
         ..trackedPlayer = null