Refactor and cancellation improvements

Ruben2776 · Jan 1, 2025 · 76d0418 · 76d0418
1 parent 357d1d3
commit 76d0418
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Showing 3 changed files with 64 additions and 59 deletions.
diff --git a/src/PicView.Avalonia/Navigation/ImageIterator.cs b/src/PicView.Avalonia/Navigation/ImageIterator.cs
@@ -459,18 +459,6 @@ public async Task NextIteration(NavigateTo navigateTo, CancellationTokenSource c
             await TimerIteration(index, cts).ConfigureAwait(false);
         }
     }
-
-    public async Task Next10Iteration(bool forwards, CancellationTokenSource cts)
-    {
-        var index = GetIteration(CurrentIndex, forwards ? NavigateTo.Next : NavigateTo.Previous, false, true);
-        await IterateToIndex(index, cts).ConfigureAwait(false);
-    }
-
-    public async Task Next100Iteration(bool forwards, CancellationTokenSource cts)
-    {
-        var index = GetIteration(CurrentIndex, forwards ? NavigateTo.Next : NavigateTo.Previous, false, false, true);
-        await IterateToIndex(index, cts).ConfigureAwait(false);
-    }
 
     public async Task IterateToIndex(int index, CancellationTokenSource cts)
     {
@@ -568,7 +556,7 @@ await Dispatcher.UIThread.InvokeAsync(() =>
                         });
                     }
 
-                    await PreLoader.PreLoadAsync(CurrentIndex, ImagePaths.Count, IsReversed, ImagePaths, cts.Token)
+                    await PreLoader.PreLoadAsync(CurrentIndex, ImagePaths.Count, IsReversed, ImagePaths)
                         .ConfigureAwait(false);
                 }
 
@@ -583,6 +571,9 @@ await PreLoader.PreLoadAsync(CurrentIndex, ImagePaths.Count, IsReversed, ImagePa
             catch (OperationCanceledException)
             {
                 // Ignore
+#if DEBUG
+                Trace.WriteLine($"{nameof(IterateToIndex)} canceled");
+#endif
             }
             catch (Exception e)
             {

diff --git a/src/PicView.Avalonia/Navigation/NavigationHelper.cs b/src/PicView.Avalonia/Navigation/NavigationHelper.cs
@@ -59,18 +59,8 @@ public static async Task Navigate(bool next, MainViewModel vm)
         }
         else
         {
-            await Task.Run(async () =>
-            {
-                var navigateTo = next ? NavigateTo.Next : NavigateTo.Previous;
-
-                if (_cancellationTokenSource is not null)
-                {
-                    await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
-                }
-
-                _cancellationTokenSource = new CancellationTokenSource();
-                await vm.ImageIterator.NextIteration(navigateTo, _cancellationTokenSource).ConfigureAwait(false);
-            }).ConfigureAwait(false);
+            var navigateTo = next ? NavigateTo.Next : NavigateTo.Previous;
+            await CheckCancellationAndStartNextIteration(navigateTo, vm).ConfigureAwait(false);
         }
     }
 
@@ -80,58 +70,52 @@ public static async Task Navigate(int index, MainViewModel vm)
         {
             return;
         }
-
-        if (_cancellationTokenSource is not null)
-        {
-            await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
-        }
-
-        _cancellationTokenSource = new CancellationTokenSource();
-        await vm.ImageIterator.IterateToIndex(index, _cancellationTokenSource).ConfigureAwait(false);
+
+        await CheckCancellationAndStartIterateToIndex(index, vm).ConfigureAwait(false);
     }
 
     public static async Task Next10(MainViewModel vm)
     {
-        if (_cancellationTokenSource is not null)
+        if (!CanNavigate(vm))
         {
-            await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
+            return;
         }
-
-        _cancellationTokenSource = new CancellationTokenSource();
-        await vm.ImageIterator.Next10Iteration(true, _cancellationTokenSource).ConfigureAwait(false);
+        var currentIndex = vm.ImageIterator.CurrentIndex;
+        var index = vm.ImageIterator.GetIteration(currentIndex, NavigateTo.Next, false, true);
+        await CheckCancellationAndStartIterateToIndex(index, vm).ConfigureAwait(false);
     }
 
     public static async Task Next100(MainViewModel vm)
     {
-        if (_cancellationTokenSource is not null)
+        if (!CanNavigate(vm))
         {
-            await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
+            return;
         }
-
-        _cancellationTokenSource = new CancellationTokenSource();
-        await vm.ImageIterator.Next100Iteration(true, _cancellationTokenSource).ConfigureAwait(false);
+        var currentIndex = vm.ImageIterator.CurrentIndex;
+        var index = vm.ImageIterator.GetIteration(currentIndex, NavigateTo.Next, false, false, true);
+        await CheckCancellationAndStartIterateToIndex(index, vm).ConfigureAwait(false);
     }
 
     public static async Task Prev10(MainViewModel vm)
     {
-        if (_cancellationTokenSource is not null)
+        if (!CanNavigate(vm))
         {
-            await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
+            return;
         }
-
-        _cancellationTokenSource = new CancellationTokenSource();
-        await vm.ImageIterator.Next10Iteration(false, _cancellationTokenSource).ConfigureAwait(false);
+        var currentIndex = vm.ImageIterator.CurrentIndex;
+        var index = vm.ImageIterator.GetIteration(currentIndex, NavigateTo.Previous, false, true);
+        await CheckCancellationAndStartIterateToIndex(index, vm).ConfigureAwait(false);
     }
 
     public static async Task Prev100(MainViewModel vm)
     {
-        if (_cancellationTokenSource is not null)
+        if (!CanNavigate(vm))
         {
-            await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
+            return;
         }
-
-        _cancellationTokenSource = new CancellationTokenSource();
-        await vm.ImageIterator.Next100Iteration(false, _cancellationTokenSource).ConfigureAwait(false);
+        var currentIndex = vm.ImageIterator.CurrentIndex;
+        var index = vm.ImageIterator.GetIteration(currentIndex, NavigateTo.Previous, false, false, true);
+        await CheckCancellationAndStartIterateToIndex(index, vm).ConfigureAwait(false);
     }
 
     /// <summary>
@@ -628,6 +612,36 @@ public static async Task LoadPicFromDirectoryAsync(string file, MainViewModel vm
     #endregion
 
     #region Private helpers
+
+    private static async Task CheckCancellationAndStartNextIteration(NavigateTo navigateTo, MainViewModel vm)
+    {
+        await Task.Run(async () =>
+        {
+            if (_cancellationTokenSource is not null)
+            {
+                await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
+            }
+
+            _cancellationTokenSource = new CancellationTokenSource();
+            await vm.ImageIterator.NextIteration(navigateTo, _cancellationTokenSource).ConfigureAwait(false);
+            _cancellationTokenSource.CancelAfter(TimeSpan.FromMinutes(5));
+        }).ConfigureAwait(false);
+    }
+
+    private static async Task CheckCancellationAndStartIterateToIndex(int index, MainViewModel vm)
+    {
+        await Task.Run(async () =>
+        {
+            if (_cancellationTokenSource is not null)
+            {
+                await _cancellationTokenSource.CancelAsync().ConfigureAwait(false);
+            }
+
+            _cancellationTokenSource = new CancellationTokenSource();
+            await vm.ImageIterator.IterateToIndex(index, _cancellationTokenSource).ConfigureAwait(false);
+            _cancellationTokenSource.CancelAfter(TimeSpan.FromMinutes(5));
+        }).ConfigureAwait(false);
+    }
 
     /// <summary>
     /// Gets the list of files in the next or previous folder.

diff --git a/src/PicView.Avalonia/Preloading/Preloader.cs b/src/PicView.Avalonia/Preloading/Preloader.cs
@@ -297,15 +297,14 @@ public bool Remove(int key, List<string> list)
         }
     }
 
-    public async Task PreLoadAsync(int currentIndex, int count, bool reverse, List<string> list,
-        CancellationToken cancellationToken = default)
+    public async Task PreLoadAsync(int currentIndex, int count, bool reverse, List<string> list)
     {
-        using var cts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
+        using var cts = new CancellationTokenSource();
         cts.CancelAfter(TimeSpan.FromMinutes(5));
 
         try
         {
-            await PreLoadInternalAsync(currentIndex, count, reverse, list);
+            await PreLoadInternalAsync(currentIndex, count, reverse, list, cts.Token);
         }
         catch (OperationCanceledException)
         {
@@ -319,7 +318,7 @@ public async Task PreLoadAsync(int currentIndex, int count, bool reverse, List<s
         }
     }
 
-    private async Task PreLoadInternalAsync(int currentIndex, int count, bool reverse, List<string> list)
+    private async Task PreLoadInternalAsync(int currentIndex, int count, bool reverse, List<string> list, CancellationToken token)
     {
         if (list == null)
         {
@@ -359,7 +358,8 @@ private async Task PreLoadInternalAsync(int currentIndex, int count, bool revers
 
         var options = new ParallelOptions
         {
-            MaxDegreeOfParallelism = _config.MaxParallelism
+            MaxDegreeOfParallelism = _config.MaxParallelism,
+            CancellationToken = token
         };
 
         try