feat(player): 增加进度条拖动画面预览

test/home/home_preview_layout_test.dart

@@ -1,6 +1,7 @@
 // Author: fruit.com.cn
 
 import 'dart:async';
+import 'dart:typed_data';
 
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -13,6 +14,7 @@ import 'package:fruitshorts/core/data/models/home_feed.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 'package:fruitshorts/core/data/services/playback_thumbnail_service.dart';
 import 'package:fruitshorts/core/theme/app_theme.dart';
 import 'package:fruitshorts/l10n/app_localizations.dart';
 import 'package:fruitshorts/pages/home/home_feed_channel.dart';
@@ -609,6 +611,83 @@ void main() {
     expect(find.byIcon(Icons.refresh_rounded), findsOneWidget);
   });
 
+  testWidgets('should_show_scrub_preview_card_from_home_progress', (
+    tester,
+  ) async {
+    final controller = ValueNotifier<VideoPlayerValue>(
+      const VideoPlayerValue(
+        duration: Duration(seconds: 100),
+        position: Duration(seconds: 10),
+        isInitialized: true,
+      ),
+    );
+    final service = _nullThumbnailService();
+    addTearDown(controller.dispose);
+    addTearDown(service.dispose);
+    await tester.pumpWidget(
+      MaterialApp(
+        theme: AppTheme.light(),
+        locale: const Locale('en'),
+        supportedLocales: AppLocalizations.supportedLocales,
+        localizationsDelegates: AppLocalizations.localizationsDelegates,
+        home: Builder(
+          builder: (context) => Scaffold(
+            body: HomeFeedOverlay(
+              l10n: AppLocalizations.of(context)!,
+              drama: const Drama(
+                id: 'preview-drama',
+                title: 'Preview Drama',
+                synopsis: 'synopsis',
+                posterUrl: '',
+                totalEpisodes: 8,
+              ),
+              episode: const Episode(
+                id: 'preview-episode',
+                number: 1,
+                title: 'Episode 1',
+                isFree: true,
+              ),
+              controller: controller,
+              locked: false,
+              liked: false,
+              saved: false,
+              visible: true,
+              boosting: false,
+              thumbnailService: service,
+              onTogglePlay: () {},
+              onBoostStart: () {},
+              onBoostEnd: () {},
+              onLike: () {},
+              onSave: () {},
+              onComments: () {},
+              onShare: () {},
+              onDetail: () {},
+              onOpenFullPlayer: () {},
+              onMore: () {},
+              onScrubStart: () {},
+              onSeek: (_) {},
+            ),
+          ),
+        ),
+      ),
+    );
+    await tester.pumpAndSettle();
+
+    final gesture = await tester.startGesture(
+      tester.getCenter(find.byKey(const Key('home-feed-progress'))),
+    );
+    await gesture.moveBy(const Offset(60, 0));
+    await tester.pump();
+
+    expect(find.byKey(const Key('scrub-preview-card')), findsOneWidget);
+    expect(find.byKey(const Key('scrub-preview-poster')), findsOneWidget);
+    expect(find.textContaining('/ 01:40'), findsOneWidget);
+
+    await gesture.up();
+    await tester.pump();
+    expect(find.byKey(const Key('scrub-preview-card')), findsNothing);
+  });
+
   testWidgets('should_seek_from_series_bar_when_overlay_is_cleared', (
     tester,
   ) async {
@@ -683,3 +762,20 @@ void main() {
     expect(seeked!.inSeconds, greaterThan(0));
   });
 }
+
+PlaybackThumbnailService _nullThumbnailService() {
+  return PlaybackThumbnailService(
+    frameLoader: _NullThumbnailLoader(),
+    sourceResolver: (_) =>
+        const PlaybackThumbnailSource(remoteUrl: 'https://example/video.mp4'),
+    prefetchDelay: const Duration(hours: 1),
+  );
+}
+
+class _NullThumbnailLoader implements PlaybackThumbnailFrameLoader {
+  @override
+  Future<ByteData?> load(PlaybackThumbnailFrameRequest request) async => null;
+
+  @override
+  void dispose() {}
+}