Restart schedule from bottom active item

Tornado3_2026Election/Services/ChannelScheduleEngine.cs

@@ -26,6 +26,7 @@ public sealed class ChannelScheduleEngine
     private TaskCompletionSource<bool>? _advanceSignal;
     private Guid? _lastPlaybackItemId;
     private Guid? _skipCurrentItemId;
+    private Guid? _restartFromTopAfterItemId;
     private ChannelScheduleItem? _directPlaybackItem;
     private PreparedCutFrame? _preparedCutFrame;
 
@@ -77,6 +78,12 @@ public sealed class ChannelScheduleEngine
     {
         if (IsRunning)
         {
+            if (GetNextPlayableItem() is null)
+            {
+                await RestartFromTopAsync().ConfigureAwait(false);
+                return;
+            }
+
             await AdvanceToNextAsync().ConfigureAwait(false);
             return;
         }
@@ -87,7 +94,10 @@ public sealed class ChannelScheduleEngine
         }
 
         _lastPlaybackItemId = null;
+        _skipCurrentItemId = null;
+        _restartFromTopAfterItemId = null;
         ResetDataUnavailableItems();
+        ClearStalePlaybackStatesBeforeStart();
         _playbackCts = new CancellationTokenSource();
         IsRunning = true;
         RefreshQueueMarkers();
@@ -112,6 +122,7 @@ public sealed class ChannelScheduleEngine
             ClearPreparedFrame(resetState: true);
             _lastPlaybackItemId = null;
             _skipCurrentItemId = null;
+            _restartFromTopAfterItemId = null;
             RefreshQueueMarkers();
             QueueChanged?.Invoke(this, EventArgs.Empty);
             return;
@@ -135,6 +146,7 @@ public sealed class ChannelScheduleEngine
 
         _lastPlaybackItemId = null;
         _skipCurrentItemId = null;
+        _restartFromTopAfterItemId = null;
         ClearPreparedFrame(resetState: false);
         IsRunning = false;
         RefreshQueueMarkers();
@@ -152,6 +164,8 @@ public sealed class ChannelScheduleEngine
         try
         {
             _lastPlaybackItemId = null;
+            _skipCurrentItemId = null;
+            _restartFromTopAfterItemId = null;
             ResetDataUnavailableItems();
             ClearPreparedFrame(resetState: true);
             RefreshQueueMarkers();
@@ -260,6 +274,8 @@ public sealed class ChannelScheduleEngine
     public void Reset()
     {
         _lastPlaybackItemId = null;
+        _skipCurrentItemId = null;
+        _restartFromTopAfterItemId = null;
         ClearPreparedFrame(resetState: false);
         foreach (var item in Queue)
         {
@@ -327,6 +343,37 @@ public sealed class ChannelScheduleEngine
         return Task.CompletedTask;
     }
 
+    private Task RestartFromTopAsync()
+    {
+        if (!IsRunning)
+        {
+            return Task.CompletedTask;
+        }
+
+        var activeItem = Queue.FirstOrDefault(item => item.State is ScheduleQueueItemState.OnAir or ScheduleQueueItemState.Sending);
+        if (activeItem is not null)
+        {
+            _skipCurrentItemId = activeItem.Id;
+            _restartFromTopAfterItemId = activeItem.Id;
+            _lastPlaybackItemId = null;
+            activeItem.State = ScheduleQueueItemState.Queued;
+            activeItem.LastError = string.Empty;
+            activeItem.CurrentRegionLabel = string.Empty;
+            activeItem.ClearInternalNextPreview();
+            activeItem.ClearPlaybackCountdown();
+        }
+        else
+        {
+            _lastPlaybackItemId = null;
+            _restartFromTopAfterItemId = null;
+        }
+
+        RefreshQueueMarkers();
+        QueueChanged?.Invoke(this, EventArgs.Empty);
+        _advanceSignal?.TrySetResult(true);
+        return Task.CompletedTask;
+    }
+
     public bool Remove(ChannelScheduleItem? item)
     {
         if (item is null || !item.CanDelete)
@@ -547,7 +594,7 @@ public sealed class ChannelScheduleEngine
 
         if (regionTargets.Count == 0)
         {
-            _lastPlaybackItemId = queueItem.Id;
+            MarkLastPlaybackItem(queueItem);
             MarkDataUnavailable(queueItem, "선택한 지역 조건에 송출 가능한 데이터가 없습니다.");
             RefreshQueueMarkers();
             return;
@@ -637,7 +684,7 @@ public sealed class ChannelScheduleEngine
             queueItem.CurrentRegionLabel = string.Empty;
             queueItem.ClearInternalNextPreview();
             queueItem.ClearPlaybackCountdown();
-            _lastPlaybackItemId = queueItem.Id;
+            MarkLastPlaybackItem(queueItem);
             if (playedAny)
             {
                 queueItem.State = ScheduleQueueItemState.Queued;
@@ -737,7 +784,7 @@ public sealed class ChannelScheduleEngine
         queueItem.CurrentRegionLabel = string.Empty;
         queueItem.ClearInternalNextPreview();
         queueItem.ClearPlaybackCountdown();
-        _lastPlaybackItemId = queueItem.Id;
+        MarkLastPlaybackItem(queueItem);
         if (playedAny)
         {
             queueItem.State = ScheduleQueueItemState.Queued;
@@ -1770,6 +1817,36 @@ public sealed class ChannelScheduleEngine
         return item.State is ScheduleQueueItemState.Queued or ScheduleQueueItemState.Next or ScheduleQueueItemState.Completed;
     }
 
+    private void MarkLastPlaybackItem(ChannelScheduleItem queueItem)
+    {
+        if (_restartFromTopAfterItemId == queueItem.Id)
+        {
+            _lastPlaybackItemId = null;
+            _restartFromTopAfterItemId = null;
+            return;
+        }
+
+        _lastPlaybackItemId = queueItem.Id;
+    }
+
+    private void ClearStalePlaybackStatesBeforeStart()
+    {
+        foreach (var item in Queue.Where(item => item.State is ScheduleQueueItemState.OnAir or ScheduleQueueItemState.Sending))
+        {
+            if (_preparedCutFrame?.Item.Id == item.Id)
+            {
+                continue;
+            }
+
+            item.State = ScheduleQueueItemState.Queued;
+            item.LastError = string.Empty;
+            item.CurrentRegionLabel = string.Empty;
+            item.ClearRenderedPreview();
+            item.ClearInternalNextPreview();
+            item.ClearPlaybackCountdown();
+        }
+    }
+
     private void ResetDataUnavailableItems()
     {
         foreach (var item in Queue.Where(item => item.State == ScheduleQueueItemState.DataUnavailable))