提取abs播放器抽象类

lib/shared/audio_player.dart

@@ -0,0 +1,41 @@
+import 'package:shelfsdk/audiobookshelf_api.dart';
+import 'package:vaani/features/player/core/audiobook_player.dart';
+
+abstract class AbsAudioPlayer {
+  AbsAudioPlayer._();
+
+  BookExpanded? _book;
+
+  BookExpanded? get book => _book;
+
+  Future<void> play();
+  Future<void> pause();
+  Future<void> playOrPause();
+  Future<void> next();
+  Future<void> previous();
+  Future<void> seek(Duration position, {int? index});
+  Future<void> seekInBook(Duration position);
+  Future<void> setSpeed(double speed);
+  Future<void> setVolume(double volume);
+  Future<void> switchChapter(int chapterId);
+
+  int get currentIndex;
+
+  Duration get position;
+
+  Duration get positionInChapter {
+    final globalPosition = positionInBook;
+    return globalPosition -
+        (book?.findChapterAtTime(globalPosition).start ?? Duration.zero);
+  }
+
+  Duration get positionInBook =>
+      position + (book?.tracks[currentIndex].startOffset ?? Duration.zero);
+
+  Stream<Duration> get positionStream;
+
+  Stream<Duration> get positionInChapterStream;
+
+  Stream<Duration> get positionInBookStream;
+  Stream<Duration> get bufferedPositionInBookStream;
+}