feat(app): 剧场列表增加语种筛选

lib/pages/discover/discover_logic.dart

@@ -36,6 +36,7 @@ class DiscoverLogic extends ChangeNotifier {
   Duration searchDebounce = const Duration(milliseconds: 350);
   static const int searchPageSize = 20;
   List<Drama> searchResults = const [];
+  String? selectedLanguage;
   int searchTotal = 0;
   bool searchLoading = false;
   String? searchError;
@@ -87,8 +88,32 @@ class DiscoverLogic extends ChangeNotifier {
 
   /// 搜索态展示后端结果，非搜索态展示剧场自身的可见短剧。
   List<Drama> visibleDramas(List<Drama> fallback) {
-    if (!hasSearchQuery) return fallback;
-    return searchResults;
+    if (!hasSearchQuery) return _filterByLanguage(fallback);
+    return _filterByLanguage(searchResults);
+  }
+
+  /// 当前 feed 中出现过的语种，按首次出现顺序去重。
+  List<String> languagesOf(List<Drama> dramas) {
+    final languages = <String>[];
+    for (final drama in dramas) {
+      final language = drama.language;
+      if (language.isNotEmpty && !languages.contains(language)) {
+        languages.add(language);
+      }
+    }
+    return languages;
+  }
+
+  /// 按语种筛选；null 表示全部。
+  void selectLanguage(String? code) {
+    selectedLanguage = code;
+    notify();
+  }
+
+  List<Drama> _filterByLanguage(List<Drama> dramas) {
+    final code = selectedLanguage;
+    if (code == null) return dramas;
+    return dramas.where((drama) => drama.language == code).toList();
   }
 
   Future<void> retrySearch() async {

lib/pages/discover/discover_view.dart

@@ -176,7 +176,12 @@ class _DiscoverPageState extends State<DiscoverPage> {
             child: _categories(l10n, categories),
           ),
         ),
-        if (logic.resumeRecord != null && logic.resumeDrama(allDramas) != null)
+        SliverToBoxAdapter(
+          child: Padding(
+            padding: const EdgeInsets.fromLTRB(0, 0, 0, 12),
+            child: _languages(l10n, allDramas),
+          ),
+        ),        if (logic.resumeRecord != null && logic.resumeDrama(allDramas) != null)
           SliverToBoxAdapter(
             child: Padding(
               padding: const EdgeInsets.fromLTRB(16, 0, 16, 14),
@@ -427,6 +432,69 @@ class _DiscoverPageState extends State<DiscoverPage> {
     );
   }
 
+  Widget _languages(AppLocalizations l10n, List<Drama> dramas) {
+    final languages = logic.languagesOf(dramas);
+    if (languages.isEmpty) return const SizedBox.shrink();
+    final selected = logic.selectedLanguage;
+    return SizedBox(
+      key: const Key('discover-language-chips'),
+      height: AppDimens.tapTarget,
+      child: ListView(
+        padding: const EdgeInsets.symmetric(horizontal: 14),
+        scrollDirection: Axis.horizontal,
+        children: [
+          _languageChip(
+            key: const Key('discover-language-all'),
+            label: l10n.all,
+            selected: selected == null,
+            onTap: () => logic.selectLanguage(null),
+          ),
+          for (final language in languages)
+            _languageChip(
+              key: Key('discover-language-$language'),
+              label: _languageLabel(l10n, language),
+              selected: selected == language,
+              onTap: () => logic.selectLanguage(language),
+            ),
+        ],
+      ),
+    );
+  }
+
+  Widget _languageChip({
+    required Key key,
+    required String label,
+    required bool selected,
+    required VoidCallback onTap,
+  }) {
+    return Padding(
+      padding: const EdgeInsets.only(right: 8),
+      child: Center(
+        child: ChoiceChip(
+          key: key,
+          label: Text(label),
+          selected: selected,
+          showCheckmark: false,
+          onSelected: (_) => onTap(),
+          selectedColor: AppColors.blue,
+          backgroundColor: const Color(0xFF29272B),
+          side: BorderSide.none,
+          labelStyle: TextStyle(
+            color: selected ? AppColors.onPrimary : AppColors.muted,
+            fontSize: AppDimens.chipFont,
+            fontWeight: selected ? FontWeight.w700 : FontWeight.w500,
+          ),
+        ),
+      ),
+    );
+  }
+
+  String _languageLabel(AppLocalizations l10n, String code) {
+    if (code == 'zh-CN' || code == 'zh') return l10n.languageChinese;
+    if (code == 'id') return l10n.languageIndonesian;
+    if (code == 'en') return l10n.languageEnglish;
+    return code;
+  }
   Widget _continueCard(
     AppLocalizations l10n,
     Drama drama,

test/catalog/drama_model_test.dart

@@ -13,6 +13,7 @@ void main() {
       'totalEpisodes': 77,
       'isHot': true,
       'viewCount': 3100000,
+      'language': 'zh-CN',
       'preview': {
         'id': 9,
         'number': 1,
@@ -27,6 +28,7 @@ void main() {
     expect(drama.episodes.single.videoUrl, '/files/episode/9.mp4');
     expect(drama.episodeCount, 77);
     expect(drama.isHot, isTrue);
+    expect(drama.language, 'zh-CN');
   });
 
   test('should_have_no_episodes_when_list_card_has_no_playable_preview', () {

test/discover/discover_language_filter_test.dart

@@ -0,0 +1,90 @@
+// Author: fruit.com.cn
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:shared_preferences_platform_interface/in_memory_shared_preferences_async.dart';
+import 'package:shared_preferences_platform_interface/shared_preferences_async_platform_interface.dart';
+
+import 'package:fruitshorts/app.dart';
+import 'package:fruitshorts/core/data/models/content_category.dart';
+import 'package:fruitshorts/core/data/models/drama.dart';
+import 'package:fruitshorts/core/data/models/home_feed.dart';
+import 'package:fruitshorts/core/data/repositories/category_repository.dart';
+import 'package:fruitshorts/core/data/repositories/favorite_repository.dart';
+import 'package:fruitshorts/core/data/repositories/playback_repository.dart';
+import 'package:fruitshorts/core/data/repositories/watch_history_repository.dart';
+
+import '../support/fake_catalog.dart';
+import '../support/fake_interaction_repositories.dart';
+import '../support/fake_notice_repository.dart';
+import '../support/widget_player.dart';
+
+void main() {
+  setUp(() {
+    SharedPreferencesAsyncPlatform.instance =
+        InMemorySharedPreferencesAsync.empty();
+  });
+
+  testWidgets('should_filter_theater_grid_when_language_chip_is_tapped', (
+    tester,
+  ) async {
+    tester.view.physicalSize = const Size(390, 844);
+    tester.view.devicePixelRatio = 1;
+    addTearDown(tester.view.resetPhysicalSize);
+    addTearDown(tester.view.resetDevicePixelRatio);
+
+    await tester.pumpWidget(
+      LumaDramaApp(
+        playerFactory: createWidgetPlayer,
+        catalogRepository: FakeCatalogRepository(),
+        categoryRepository: _MixedLanguageCategoryRepository(),
+        watchHistoryRepository: InMemoryWatchHistoryRepository(),
+        favoriteRepository: InMemoryFavoriteRepository(),
+        playbackRepository: FakePlaybackRepository(),
+        commentRepository: FakeCommentRepository(),
+        interactionRepository: FakeInteractionRepository(),
+        noticeRepository: FakeNoticeRepository(),
+      ),
+    );
+    await tester.pumpAndSettle();
+    await tester.tap(find.byKey(const Key('tab-discover')));
+    await tester.pumpAndSettle();
+
+    expect(find.byKey(const Key('home-drama-card-zh-demo')), findsOneWidget);
+    expect(find.byKey(const Key('home-drama-card-id-demo')), findsOneWidget);
+
+    await tester.tap(find.byKey(const Key('discover-language-zh-CN')));
+    await tester.pumpAndSettle();
+
+    expect(find.byKey(const Key('home-drama-card-zh-demo')), findsOneWidget);
+    expect(find.byKey(const Key('home-drama-card-id-demo')), findsNothing);
+  });
+}
+
+class _MixedLanguageCategoryRepository implements CategoryRepository {
+  @override
+  Future<List<ContentCategory>> fetchCategories() async => const [];
+
+  @override
+  Future<HomeFeed> fetchDiscoverFeed() async => HomeFeed(
+    sections: [
+      FeedSection(
+        code: 'hot',
+        title: 'Hot',
+        dramas: [
+          _drama('zh-demo', 'Chinese Demo', 'zh-CN'),
+          _drama('id-demo', 'Indonesian Demo', 'id'),
+        ],
+      ),
+    ],
+  );
+}
+
+Drama _drama(String id, String title, String language) => Drama(
+  id: id,
+  title: title,
+  synopsis: '$title synopsis',
+  posterUrl: '/files/$id.png',
+  language: language,
+  detailLoaded: true,
+);

test/discover/discover_logic_test.dart

@@ -8,7 +8,8 @@ import 'package:fruitshorts/pages/discover/discover_logic.dart';
 
 import '../support/fake_watch_history.dart';
 
-Drama _drama(String id, {List<int> numbers = const [1, 2, 3]}) => Drama(
+Drama _drama(String id, {List<int> numbers = const [1, 2, 3], String language = ''}) => Drama(
+  language: language,
   id: id,
   title: id,
   synopsis: 'synopsis',
@@ -64,6 +65,36 @@ void main() {
     logic.dispose();
   });
 
+  test('should_filter_visible_dramas_when_language_is_selected', () {
+    final logic = DiscoverLogic(history: FakeWatchHistory(), drama: _drama('s'));
+    final dramas = [
+      _drama('zh', language: 'zh-CN'),
+      _drama('id', language: 'id'),
+      _drama('unknown'),
+    ];
+
+    expect(logic.visibleDramas(dramas), hasLength(3));
+
+    logic.selectLanguage('id');
+    expect(logic.visibleDramas(dramas).map((item) => item.id), ['id']);
+
+    logic.selectLanguage(null);
+    expect(logic.visibleDramas(dramas), hasLength(3));
+    logic.dispose();
+  });
+
+  test('should_list_distinct_languages_when_feed_has_cards', () {
+    final logic = DiscoverLogic(history: FakeWatchHistory(), drama: _drama('s'));
+    final dramas = [
+      _drama('zh', language: 'zh-CN'),
+      _drama('id', language: 'id'),
+      _drama('id2', language: 'id'),
+      _drama('unknown'),
+    ];
+
+    expect(logic.languagesOf(dramas), ['zh-CN', 'id']);
+    logic.dispose();
+  });
   test('should_have_no_resume_position_when_server_has_no_record', () async {
     final history = FakeWatchHistory();
     final logic = DiscoverLogic(