Code Quality: Remove thumbnail cache to simplify logic and improve performance

src/Files.App/Data/Models/ItemViewModel.cs

@@ -937,117 +937,142 @@ private async Task<BitmapImage> GetShieldIcon()
 return shieldIcon;
 }
 
-private async Task LoadItemThumbnailAsync(ListedItem item)
+/// <summary>
+/// Loads basic icon using ReturnIconOnly flag
+/// </summary>
+/// <param name="item"></param>
+/// <returns></returns>
+private async Task LoadBasicIconAsync(ListedItem item)
 {
-var thumbnailSize = folderSettings.GetRoundedIconSize();
-
-if (item.IsLibrary || item.PrimaryItemAttribute == StorageItemTypes.File || item.IsArchive)
-{
-var getIconOnly = UserSettingsService.FoldersSettingsService.ShowThumbnails == false || thumbnailSize < 48;
-var getThumbnailOnly = !item.IsExecutable && !getIconOnly;
-var iconInfo = await FileThumbnailHelper.GetIconAsync(
+// Get icon
+var icon = await FileThumbnailHelper.GetIconAsync(
 item.ItemPath,
-thumbnailSize,
+folderSettings.GetRoundedIconSize(),
+item.IsFolder,
 false,
-getThumbnailOnly,
-getIconOnly ? IconOptions.ReturnIconOnly : IconOptions.None);
+IconOptions.ReturnIconOnly);
 
-if (!iconInfo.isIconCached)
-{
-// Assign a placeholder icon while trying to get a cached thumbnail
-if (iconInfo.IconData is not null)
-{
-await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
-{
-item.FileImage = await iconInfo.IconData.ToBitmapAsync();
-}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
-}
-
-// Loop until cached thumbnail is loaded or timeout is reached
-var cancellationTokenSource = new CancellationTokenSource(3000);
-while (!iconInfo.isIconCached)
-{
-iconInfo = await FileThumbnailHelper.GetIconAsync(
-item.ItemPath,
-thumbnailSize,
-false,
-getThumbnailOnly,
-getIconOnly ? IconOptions.ReturnIconOnly : IconOptions.None);
-
-if (cancellationTokenSource.Token.IsCancellationRequested)
-break;
-
-await Task.Delay(500);
-}
-}
-
-if (iconInfo.IconData is not null)
+if (icon.IconData is not null)
+{
+await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
 {
-await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
+var image = await icon.IconData.ToBitmapAsync();
+if (image is not null)
 {
-// Assign the thumbnail/icon to the listed item
-item.FileImage = await iconInfo.IconData.ToBitmapAsync();
+// Assign FileImage property
+item.FileImage = image;
 
-// Add the file icon to the DefaultIcons list
+// Add file icon to the DefaultIcons list
 if
 (
+!item.IsFolder &&
 !DefaultIcons.ContainsKey(item.FileExtension.ToLowerInvariant()) &&
 !string.IsNullOrEmpty(item.FileExtension) &&
 !item.IsShortcut &&
 !item.IsExecutable
 )
 {
-var fileIcon = await FileThumbnailHelper.GetIconAsync(
-item.ItemPath,
-thumbnailSize,
-false,
-false,
-IconOptions.ReturnIconOnly);
-
-var bitmapImage = await fileIcon.IconData.ToBitmapAsync();
-DefaultIcons.TryAdd(item.FileExtension.ToLowerInvariant(), bitmapImage);
+DefaultIcons.TryAdd(item.FileExtension.ToLowerInvariant(), image);
 }
+}
+}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
+}
 
-}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
-}
+// Get icon overlay
+var iconOverlay = await FileThumbnailHelper.GetIconOverlayAsync(item.ItemPath, true);
+if (iconOverlay is not null)
+{
+await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
+{
+item.IconOverlay = await iconOverlay.ToBitmapAsync();
+item.ShieldIcon = await GetShieldIcon();
+}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
+}
+}
+
+/// <summary>
+/// Loads thumbnail without any flags
+/// Returns early if thumbnails aren't needed for this item (eg. if thumbnails are disabled or size is too small)
+/// </summary>
+/// <param name="item"></param>
+/// <returns></returns>
+private async Task LoadThumbnailAsync(ListedItem item)
+{
+// Cancel if thumbnails aren't enabled
+var thumbnailSize = folderSettings.GetRoundedIconSize();
+if (UserSettingsService.FoldersSettingsService.ShowThumbnails == false || thumbnailSize < 48)
+return;
+
+// Get thumbnail
+var icon = await FileThumbnailHelper.GetIconAsync(
+item.ItemPath,
+thumbnailSize,
+item.IsFolder,
+false,
+IconOptions.None);
 
-var iconOverlay = await FileThumbnailHelper.GetIconOverlayAsync(item.ItemPath, false);
-if (iconOverlay is not null)
+if (icon.IconData is not null)
+{
+await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
 {
-// Assign the icon overlay to the listed item
-await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
-{
-item.IconOverlay = await iconOverlay.ToBitmapAsync();
-item.ShieldIcon = await GetShieldIcon();
-}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
-}
+// Assign FileImage property
+var image = await icon.IconData.ToBitmapAsync();
+if (image is not null)
+item.FileImage = image;
+}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
 }
-else
+}
+
+/// <summary>
+/// Tries getting a cached thumbnail from the system. This is usually only needed for cloud locations, otherwise LoadThumbnailAsync does the job.
+/// </summary>
+/// <param name="item"></param>
+/// <returns></returns>
+private async Task LoadCachedThumbnailAsync(ListedItem item)
+{
+// Cancel for exe files which don't need thumbnails
+if (item.IsExecutable)
+return;
+
+// Cancel if thumbnails aren't enabled
+var thumbnailSize = folderSettings.GetRoundedIconSize();
+if (UserSettingsService.FoldersSettingsService.ShowThumbnails == false || thumbnailSize < 48)
+return;
+
+// Get icon
+var icon = await FileThumbnailHelper.GetIconAsync(
+item.ItemPath,
+thumbnailSize,
+item.IsFolder,
+true,
+IconOptions.None);
+
+// Loop until cached thumbnail is loaded or timeout is reached
+var cancellationTokenSource = new CancellationTokenSource(3000);
+while (true)
 {
-var getIconOnly = UserSettingsService.FoldersSettingsService.ShowThumbnails == false || thumbnailSize < 48;
-var iconInfo = await FileThumbnailHelper.GetIconAsync(
+icon = await FileThumbnailHelper.GetIconAsync(
 item.ItemPath,
 thumbnailSize,
+item.IsFolder,
 true,
-false, getIconOnly ? IconOptions.ReturnIconOnly : IconOptions.None);
+IconOptions.None);
 
-if (iconInfo.IconData is not null)
-{
-await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
-{
-item.FileImage = await iconInfo.IconData.ToBitmapAsync();
-}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
-}
+if (icon.isIconCached || cancellationTokenSource.Token.IsCancellationRequested)
+break;
+
+await Task.Delay(500);
+}
 
-var iconOverlay = await FileThumbnailHelper.GetIconOverlayAsync(item.ItemPath, true);
-if (iconOverlay is not null)
+// Update FileImage property if icon is cached
+if (icon.isIconCached)
+{
+await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
 {
-await dispatcherQueue.EnqueueOrInvokeAsync(async () =>
-{
-item.IconOverlay = await iconOverlay.ToBitmapAsync();
-item.ShieldIcon = await GetShieldIcon();
-}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
-}
+var image = await icon.IconData.ToBitmapAsync();
+if (image is not null)
+item.FileImage = image;
+}, Microsoft.UI.Dispatching.DispatcherQueuePriority.Low);
 }
 }
 
@@ -1092,7 +1117,7 @@ await Task.Run(async () =>
 }
 
 cts.Token.ThrowIfCancellationRequested();
-_ = LoadItemThumbnailAsync(item);
+await LoadBasicIconAsync(item);
 
 if (item.IsLibrary || item.PrimaryItemAttribute == StorageItemTypes.File || item.IsArchive)
 {
@@ -1198,6 +1223,14 @@ await dispatcherQueue.EnqueueOrInvokeAsync(() =>
 SetFileTag(item);
 });
 }
+else
+{
+// Load cached thumbnail for cloud files
+if (item.SyncStatusUI.SyncStatus != CloudDriveSyncStatus.NotSynced && item.SyncStatusUI.SyncStatus != CloudDriveSyncStatus.Unknown)
+_ = LoadCachedThumbnailAsync(item);
+else
+_ = LoadThumbnailAsync(item);
+}
 
 if (loadGroupHeaderInfo)
 {