Use last modified time for image viewer sorting

StabilityMatrix.Avalonia/ViewModels/Inference/ImageFolderCardViewModel.cs

@@ -1,6 +1,4 @@
 using System;
-using System.Reactive.Linq;
-using System.Threading;
 using System.Threading.Tasks;
 using Avalonia.Controls;
 using DynamicData;
@@ -27,12 +25,6 @@ public partial class ImageFolderCardViewModel : ViewModelBase
     private readonly SourceCache<LocalImageFile, string> localImagesSource =
         new(imageFile => imageFile.RelativePath);
 
-    /// <summary>
-    /// Collection of image files to display
-    /// </summary>
-    public IObservableCollection<LocalImageFile> LocalImages { get; } =
-        new ObservableCollectionExtended<LocalImageFile>();
-
     /// <summary>
     /// Collection of image items to display
     /// </summary>
@@ -49,6 +41,8 @@ public partial class ImageFolderCardViewModel : ViewModelBase
         this.imageIndexService = imageIndexService;
         this.settingsManager = settingsManager;
 
+        var minDatetime = DateTimeOffset.FromUnixTimeMilliseconds(0);
+
         localImagesSource
             .Connect()
             .DeferUntilLoaded()
@@ -62,6 +56,7 @@ public partial class ImageFolderCardViewModel : ViewModelBase
                             : imageFile.GetFullPath(settingsManager.ImagesDirectory)
                     }
             )
+            .SortBy(x => x.LocalImageFile?.LastModifiedAt ?? minDatetime, SortDirection.Descending)
             .Bind(Items)
             .Subscribe();
     }

StabilityMatrix.Core/Services/ImageIndexService.cs

@@ -80,7 +80,9 @@ public class ImageIndexService : IImageIndexService
             var localImage = new LocalImageFile
             {
                 RelativePath = relativePath,
-                ImageType = imageType
+                ImageType = imageType,
+                CreatedAt = file.Info.CreationTimeUtc,
+                LastModifiedAt = file.Info.LastWriteTimeUtc
             };
 
             // Insert into database