sleeptimer

lib/features/sleep_timer/core/sleep_timer.dart

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+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_animate/flutter_animate.dart';
+import 'package:just_audio/just_audio.dart';
+import 'package:whispering_pages/features/player/core/audiobook_player.dart';
+
+/// this timer pauses the music player after a certain duration
+///
+/// watches the state of the music player and pauses it when the timer is up
+/// timer is cancelled when the music player is paused or stopped
+class SleepTimer {
+  /// The duration after which the music player will be paused
+  final Duration duration;
+
+  /// The player to be paused
+  final AudiobookPlayer player;
+
+  /// The timer that will pause the player
+  Timer? timer;
+
+  /// for internal use only
+  /// when the timer was started
+  DateTime? startedAt;
+
+  SleepTimer({required this.duration, required this.player}) {
+    player.playbackEventStream.listen((event) {
+      if (event.processingState == ProcessingState.completed ||
+          event.processingState == ProcessingState.idle) {
+        reset();
+      }
+    });
+
+    /// pause the player when the timer is up
+    player.playerStateStream.listen((state) {
+      if (state.playing && timer == null) {
+        startTimer();
+      } else if (!state.playing) {
+        reset();
+      }
+    });
+    debugPrint('SleepTimer created with duration: $duration');
+  }
+
+  /// resets the timer
+  void reset() {
+    if (timer != null) {
+      timer!.cancel();
+      debugPrint(
+        'SleepTimer cancelled timer, remaining time: $remainingTime, duration: $duration',
+      );
+      timer = null;
+    }
+  }
+
+  /// starts the timer
+  void startTimer() {
+    reset();
+    timer = Timer(duration, () {
+      player.pause();
+      reset();
+      debugPrint('SleepTimer paused player after $duration');
+    });
+    startedAt = DateTime.now();
+    debugPrint('SleepTimer started for $duration at $startedAt');
+  }
+
+  Duration get remainingTime {
+    if (timer == null) {
+      return Duration.zero;
+    }
+    final elapsed = DateTime.now().difference(startedAt!);
+    return duration - elapsed;
+  }
+
+  /// a stream that emits the remaining time every second
+  Stream<Duration> get remainingTimeStream async* {
+    while (timer != null) {
+      yield remainingTime;
+      await Future.delayed(0.5.seconds);
+    }
+  }
+
+  /// dispose the timer
+  void dispose() {
+    reset();
+    debugPrint('SleepTimer disposed');
+  }
+}