refactor: 移除媒体检测逻辑，简化代码体积

ActivityMonitor.cs

@@ -22,9 +22,8 @@ namespace TimerApp
         
         // 状态检测缓存
         private int _checkTickCounter;
-        private const int CheckIntervalTicks = 3; // 每3秒检查一次空闲/媒体状态
+        private const int CheckIntervalTicks = 3; // 每3秒检查一次空闲状态
         private long _cachedIdleMs;
-        private bool _cachedMediaPlaying;
 
         // 配置 (默认值)
         public TimeSpan WorkDuration { get; set; } = TimeSpan.FromMinutes(20);
@@ -47,7 +46,6 @@ namespace TimerApp
 
         public ActivityMonitor()
         {
-            SystemEvents.PowerModeChanged += OnPowerModeChanged;
         }
 
         public void Start()
@@ -126,7 +124,7 @@ namespace TimerApp
         {
             // 在锁外执行耗时的系统检测
             long idleMs = 0;
-            bool? newMediaPlaying = null;
+            bool shouldUpdate = false;
 
             lock (_lock)
             {
@@ -139,27 +137,25 @@ namespace TimerApp
                 {
                     _checkTickCounter = 0;
                     // 需要更新，但在锁外进行
-                    newMediaPlaying = true; 
+                    shouldUpdate = true; 
                 }
                 
                 // 如果不需要更新，直接使用缓存值
-                if (newMediaPlaying == null)
+                if (!shouldUpdate)
                 {
                      idleMs = _cachedIdleMs;
                 }
             }
 
             // 在锁外执行实际的检测
-            if (newMediaPlaying == true)
+            if (shouldUpdate)
             {
                 idleMs = NativeMethods.GetIdleTime();
-                bool playing = NativeMethods.IsMediaPlaying();
                 
                 // 更新缓存
                 lock (_lock)
                 {
                     _cachedIdleMs = idleMs;
-                    _cachedMediaPlaying = playing;
                 }
             }
 
@@ -170,7 +166,6 @@ namespace TimerApp
 
                 // 使用（可能是新更新的）缓存值
                 idleMs = _cachedIdleMs;
-                bool isMediaPlaying = _cachedMediaPlaying;
                 TimeSpan idleTime = TimeSpan.FromMilliseconds(idleMs);
 
                 if (CurrentState == MonitorState.Resting)
@@ -196,12 +191,13 @@ namespace TimerApp
                 else
                 {
                     // 工作/空闲模式逻辑
-                    if (idleTime > IdleThreshold || isMediaPlaying)
+                    bool isUserInactive = idleTime > IdleThreshold;
+
+                    if (isUserInactive)
                     {
-                        // 用户离开了或正在播放视频
+                        // 用户确实离开了 -> 进入空闲状态
                         if (CurrentState == MonitorState.Working)
                         {
-                            // 如果空闲时间超过阈值，状态变为空闲
                             ChangeState(MonitorState.Idle);
                         }
 
@@ -211,24 +207,17 @@ namespace TimerApp
                         {
                             _accumulatedWorkTime = TimeSpan.Zero;
                         }
-
-                        // 如果正在播放视频，不累加工作时间，但保持当前状态
-                        if (isMediaPlaying && CurrentState == MonitorState.Working)
-                        {
-                            TimeSpan remainingWork = WorkDuration - _accumulatedWorkTime;
-                            WorkProgressChanged?.Invoke(this, remainingWork);
-                        }
                     }
                     else
                     {
-                        // 用户在活动且没有播放视频
+                        // 用户在活动
                         if (CurrentState == MonitorState.Idle)
                         {
                             // 从空闲变为工作
                             ChangeState(MonitorState.Working);
                         }
 
-                        // 累加工作时间
+                        // 正常工作：累加时间
                         _accumulatedWorkTime += TimeSpan.FromSeconds(1);
 
                         // 检查是否达到工作时长
@@ -277,13 +266,6 @@ namespace TimerApp
                 _accumulatedWorkTime = TimeSpan.Zero;
                 _isPaused = false;
                 
-                // Ensure task is running
-                if (_cts == null || _cts.IsCancellationRequested)
-                {
-                     // Re-start if stopped (though Restart implies it's running)
-                     // Usually Start() calls ResetWork, so we just reset here
-                }
-
                 // Force state to Working since user manually restarted
                 ChangeState(MonitorState.Working);
 
@@ -322,18 +304,10 @@ namespace TimerApp
             if (_disposed) return;
             _disposed = true;
 
-            SystemEvents.PowerModeChanged -= OnPowerModeChanged;
+            // SystemEvents.PowerModeChanged -= OnPowerModeChanged;
             Stop();
+            GC.SuppressFinalize(this);
         }
 
-        private void OnPowerModeChanged(object sender, PowerModeChangedEventArgs e)
-        {
-            if (e.Mode == PowerModes.Resume)
-            {
-                // 系统唤醒时，强制重置媒体播放检测状态，
-                // 避免因检测线程挂起导致一直误报“正在播放”而无法进入工作状态。
-                NativeMethods.InvalidateMediaCache();
-            }
-        }
     }
 }