Release v47.2

Closes #295

.github/FUNDING.yml

@@ -1,3 +1 @@
-github: chylex
-patreon: chylex
 ko_fi: chylex

README.md

@@ -18,7 +18,7 @@ Folder organization:
 * `app/` contains a Visual Studio solution for the desktop app
 * `web/` contains source code of the [official website](https://dht.chylex.com), which can be used as a template when making your own website
 
-To start editing source code for the desktop app, install the [.NET 8 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/8.0), and then open `app/DiscordHistoryTracker.sln` in [Visual Studio](https://visualstudio.microsoft.com/downloads/) or [Rider](https://www.jetbrains.com/rider/).
+To start editing source code for the desktop app, install the [.NET 9 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/9.0), and then open `app/DiscordHistoryTracker.sln` in [Visual Studio](https://visualstudio.microsoft.com/downloads/) or [Rider](https://www.jetbrains.com/rider/).
 
 ### Building
 
@@ -28,18 +28,18 @@ To build a `Release` version of the desktop app, follow the instructions for you
 
 #### Release – Windows (64-bit)
 
-1. Install [Powershell 5](https://docs.microsoft.com/en-us/powershell/scripting/install/installing-powershell-on-windows) or newer (on Windows 10, the included version of Powershell should be enough)
+1. Install Debian in WSL and open a terminal in the project folder.
+2. Run the `app/build.wsl.sh` script.
+3. Read the [Distribution](#distribution) section below.
 
-Run the `app/build.bat` script, and read the [Distribution](#distribution) section below.
+Note: The build script expects `dotnet.exe` to be installed in `C:\Program Files\dotnet`.
 
 #### Release – Other Operating Systems
 
-1. Install the `zip` package from your repository
+1. Install the `zip` package from your repository.
-
+2. Run the `app/build.sh` script.
-Run the `app/build.sh` script, and read the [Distribution](#distribution) section below.
+3. Read the [Distribution](#distribution) section below.
 
 #### Distribution
 
-The mentioned build scripts will prepare `Release` builds ready for distribution. Once the script finishes, the `app/bin` folder will contain self-contained executables for each major operating system, and a portable version that works on all other systems but requires .NET 8 to be installed.
+The mentioned build scripts will prepare `Release` builds ready for distribution. Once the script finishes, the `app/bin` folder will contain self-contained executables for each major operating system, and a portable version that works on all other systems but requires the ASP.NET Core Runtime to be installed.
-
-Note that when building on Windows, the generated `.zip` files for Linux and Mac will not have correct file permissions, so it will not be possible to run them by double-clicking the executable. Since .NET 8 fixed several issues with publishing Windows executables on Linux, I recommend using Linux to build the app for all operating systems.

app/.editorconfig

@@ -0,0 +1,2 @@
+[*.cs]
+propertychanged.auto_notify = false

app/.idea/.idea.DiscordHistoryTracker/.idea/avalonia.xml

@@ -13,6 +13,7 @@
         <entry key="Desktop/Main/Controls/MessageFilterPanel.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Controls/ServerConfigurationPanel.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Controls/StatusBar.axaml" value="Desktop/Desktop.csproj" />
+        <entry key="Desktop/Main/Dialogs/NewDatabaseSettingsDialog.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/MainWindow.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/AdvancedPage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/DatabasePage.axaml" value="Desktop/Desktop.csproj" />

app/Desktop/App.axaml

@@ -51,9 +51,56 @@
 
         <Style Selector="Expander">
             <Setter Property="MinHeight" Value="40" />
+            <Setter Property="Padding" Value="12" />
             <Setter Property="HorizontalAlignment" Value="Stretch" />
         </Style>
 
+        <Style Selector="TreeViewItem:not(:empty) /template/ Panel#PART_ExpandCollapseChevronContainer">
+            <Setter Property="Cursor" Value="Hand" />
+            <Setter Property="Margin" Value="0 0 5 0" />
+        </Style>
+        <Style Selector="TreeViewItem:empty /template/ Panel#PART_ExpandCollapseChevronContainer">
+            <Setter Property="Margin" Value="10 0" />
+        </Style>
+        <Style Selector="TreeViewItem[Level=0]:empty /template/ Panel#PART_ExpandCollapseChevronContainer">
+            <Setter Property="Margin" Value="0" />
+            <Setter Property="Width" Value="0" />
+        </Style>
+        <Style Selector="TreeViewItem /template/ ToggleButton#PART_ExpandCollapseChevron">
+            <Setter Property="Width" Value="18" />
+            <Setter Property="Height" Value="32" />
+        </Style>
+        <Style Selector="TreeViewItem /template/ ToggleButton#PART_ExpandCollapseChevron > Border">
+            <Setter Property="Padding" Value="2 10 3 10" />
+        </Style>
+
+        <Style Selector="TreeView.noSelection">
+            <Style Selector="^ TreeViewItem /template/ Border#PART_LayoutRoot">
+                <Setter Property="Background" Value="{DynamicResource TreeViewItemBackground}" />
+                <Setter Property="BorderBrush" Value="{DynamicResource TreeViewItemBorderBrush}" />
+            </Style>
+            <Style Selector="^ TreeViewItem /template/ Border#PART_LayoutRoot > ContentPresenter#PART_HeaderPresenter">
+                <Setter Property="Foreground" Value="{DynamicResource TreeViewItemForeground}" />
+            </Style>
+            <Style Selector="^ TreeViewItem:disabled /template/ Border#PART_LayoutRoot">
+                <Setter Property="Background" Value="{DynamicResource TreeViewItemBackgroundDisabled}" />
+                <Setter Property="BorderBrush" Value="{DynamicResource TreeViewItemBorderBrushDisabled}" />
+            </Style>
+            <Style Selector="^ TreeViewItem:disabled /template/ Border#PART_LayoutRoot > ContentPresenter#PART_HeaderPresenter">
+                <Setter Property="Foreground" Value="{DynamicResource TreeViewItemForegroundDisabled}" />
+            </Style>
+        </Style>
+
+        <Style Selector="Panel.buttons">
+            <Setter Property="Margin" Value="0 20 0 0" />
+        </Style>
+        <Style Selector="Panel.buttons > WrapPanel">
+            <Setter Property="ItemSpacing" Value="8" />
+        </Style>
+        <Style Selector="Panel.buttons Button">
+            <Setter Property="MinWidth" Value="80" />
+        </Style>
+
     </Application.Styles>
 
     <Application.Resources>

app/Desktop/Arguments.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 using DHT.Utils.Logging;
 
@@ -9,7 +8,7 @@ sealed class Arguments {
 	
 	private const int FirstArgument = 1;
 	
-	public static Arguments Empty => new (Array.Empty<string>());
+	public static Arguments Empty => new ([]);
 	
 	public bool Console { get; }
 	public string? DatabaseFile { get; }
@@ -51,7 +50,7 @@ sealed class Arguments {
 					continue;
 				
 				case "-port": {
-					if (!ushort.TryParse(value, out var port)) {
+					if (!ushort.TryParse(value, out ushort port)) {
 						Log.Warn("Invalid port number: " + value);
 					}
 					else {
@@ -66,11 +65,11 @@ sealed class Arguments {
 					continue;
 				
 				case "-concurrentdownloads":
-					if (!ulong.TryParse(value, out var concurrentDownloads) || concurrentDownloads == 0) {
+					if (!ulong.TryParse(value, out ulong concurrentDownloads) || concurrentDownloads == 0) {
 						Log.Warn("Invalid concurrent downloads count: " + value);
 					}
 					else if (concurrentDownloads > 10) {
-						Log.Warn("Limiting concurrent downloads to 10");
+						Log.Warn("Limiting concurrent downloads to 10.");
 						ConcurrentDownloads = 10;
 					}
 					else {

app/Desktop/Common/AvaloniaObsevableValueExtensions.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using DHT.Utils.Observables;
+
+namespace DHT.Desktop.Common;
+
+static class AvaloniaObsevableValueExtensions {
+	public static IDisposable SubscribeLastOnUI<T>(this ObservableValue<T> observable, Action<T> action, TimeSpan delayBetweenRuns) {
+		Task Action(T value, CancellationToken cancellationToken) {
+			action(value);
+			return Task.Delay(delayBetweenRuns, cancellationToken);
+		}
+		
+		return observable.SubscribeLast(Action, TaskScheduler.FromCurrentSynchronizationContext());
+	}
+}

app/Desktop/Common/AvaloniaReflection.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections;
+using System.Reflection;
+using Avalonia.Interactivity;
+
+namespace DHT.Desktop.Common;
+
+static class AvaloniaReflection {
+	private static FieldInfo InteractiveEventHandlersField { get; } = typeof(Interactive).GetField("_eventHandlers", BindingFlags.Instance | BindingFlags.NonPublic)!;
+	
+	public static void Check() {
+		if (InteractiveEventHandlersField == null) {
+			throw new InvalidOperationException("Missing field: " + nameof(InteractiveEventHandlersField));
+		}
+		
+		if (InteractiveEventHandlersField.FieldType.ToString() != "System.Collections.Generic.Dictionary`2[Avalonia.Interactivity.RoutedEvent,System.Collections.Generic.List`1[Avalonia.Interactivity.Interactive+EventSubscription]]") {
+			throw new InvalidOperationException("Invalid field type: " + nameof(InteractiveEventHandlersField) + " = " + InteractiveEventHandlersField.FieldType);
+		}
+	}
+	
+	public static IList? GetEventHandler(Interactive target, RoutedEvent routedEvent) {
+		IDictionary? eventHandlers = (IDictionary?) InteractiveEventHandlersField.GetValue(target);
+		return (IList?) eventHandlers?[routedEvent];
+	}
+}

app/Desktop/Common/DatabaseGui.cs

@@ -20,7 +20,7 @@ static class DatabaseGui {
 	private const string DatabaseFileInitialName = "archive.dht";
 	
 	private static readonly IReadOnlyList<FilePickerFileType> DatabaseFileDialogFilter = [
-		FileDialogs.CreateFilter("Discord History Tracker Database", ["dht"])
+		FileDialogs.CreateFilter("Discord History Tracker Database", ["dht"]),
 	];
 	
 	public static async Task<string[]> NewOpenDatabaseFilesDialog(Window window, string? suggestedDirectory) {
@@ -28,7 +28,7 @@ static class DatabaseGui {
 			Title = "Open Database File",
 			FileTypeFilter = DatabaseFileDialogFilter,
 			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, suggestedDirectory),
-			AllowMultiple = true
+			AllowMultiple = true,
 		});
 	}
 	
@@ -38,7 +38,7 @@ static class DatabaseGui {
 			FileTypeChoices = DatabaseFileDialogFilter,
 			SuggestedFileName = DatabaseFileInitialName,
 			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, suggestedDirectory),
-			ShowOverwritePrompt = false
+			ShowOverwritePrompt = false,
 		});
 	}
 	
@@ -52,7 +52,7 @@ static class DatabaseGui {
 		} catch (DatabaseTooNewException ex) {
 			await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' was opened in a newer version of DHT (database version " + ex.DatabaseVersion + ", app version " + ex.CurrentVersion + ").");
 		} catch (Exception ex) {
-			Log.Error(ex);
+			Log.Error("Could not open database file: " + path, ex);
 			await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' could not be opened:" + ex.Message);
 		}
 		

app/Desktop/Common/SystemUtils.cs

@@ -0,0 +1,9 @@
+using System.Diagnostics;
+
+namespace DHT.Desktop.Common;
+
+static class SystemUtils {
+	public static void OpenUrl(string url) {
+		Process.Start(new ProcessStartInfo(url) { UseShellExecute = true });
+	}
+}

app/Desktop/Desktop.csproj

@@ -15,15 +15,18 @@
   </PropertyGroup>
   
   <ItemGroup>
-    <PackageReference Include="Avalonia" Version="11.0.11" />
+    <PackageReference Include="Avalonia" Version="11.3.0" />
-    <PackageReference Include="Avalonia.Controls.DataGrid" Version="11.0.11" />
+    <PackageReference Include="Avalonia.Controls.DataGrid" Version="11.3.0" />
-    <PackageReference Include="Avalonia.Controls.ItemsRepeater" Version="11.0.11" />
+    <PackageReference Include="Avalonia.Controls.ItemsRepeater" Version="11.1.5" />
-    <PackageReference Include="Avalonia.Desktop" Version="11.0.11" />
+    <PackageReference Include="Avalonia.Desktop" Version="11.3.0" />
-    <PackageReference Include="Avalonia.Diagnostics" Version="11.0.11" Condition=" '$(Configuration)' == 'Debug' " />
+    <PackageReference Include="Avalonia.Diagnostics" Version="11.3.0" Condition=" '$(Configuration)' == 'Debug' " />
-    <PackageReference Include="Avalonia.Fonts.Inter" Version="11.0.11" />
+    <PackageReference Include="Avalonia.Fonts.Inter" Version="11.3.0" />
-    <PackageReference Include="Avalonia.ReactiveUI" Version="11.0.11" />
+    <PackageReference Include="Avalonia.ReactiveUI" Version="11.3.0" />
-    <PackageReference Include="Avalonia.Themes.Fluent" Version="11.0.11" />
+    <PackageReference Include="Avalonia.Themes.Fluent" Version="11.3.0" />
-    <PackageReference Include="CommunityToolkit.Mvvm" Version="999.0.0-build.0.g0d941a6a62" />
+    <PackageReference Include="PropertyChanged.SourceGenerator" Version="1.1.1">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
   </ItemGroup>
   
   <ItemGroup>

app/Desktop/Dialogs/CheckBox/CheckBoxDialog.axaml

@@ -8,7 +8,8 @@
         x:DataType="namespace:CheckBoxDialogModel"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
-        Width="500" SizeToContent="Height" CanResize="False"
+        MinWidth="425" MinHeight="200"
+        Width="500" Height="395" CanResize="True"
         WindowStartupLocation="CenterOwner">
 
     <Window.DataContext>
@@ -16,47 +17,35 @@
     </Window.DataContext>
 
     <Window.Styles>
-        <Style Selector="Panel.buttons">
+        <Style Selector="TreeViewItem">
-            <Setter Property="Margin" Value="0 20 0 0" />
+            <Setter Property="IsExpanded" Value="True" />
-        </Style>
-        <Style Selector="Panel.buttons > WrapPanel.right">
-            <Setter Property="HorizontalAlignment" Value="Right" />
-        </Style>
-        <Style Selector="Panel.buttons Button">
-            <Setter Property="MinWidth" Value="80" />
-        </Style>
-        <Style Selector="Panel.buttons > WrapPanel.left Button">
-            <Setter Property="Margin" Value="0 0 8 0" />
-        </Style>
-        <Style Selector="Panel.buttons > WrapPanel.right Button">
-            <Setter Property="Margin" Value="8 0 0 0" />
         </Style>
     </Window.Styles>
 
-    <StackPanel Margin="20">
+    <DockPanel Margin="20 17 20 20">
-        <ScrollViewer MaxHeight="400">
+        <Panel Classes="buttons" DockPanel.Dock="Bottom">
-            <ItemsRepeater ItemsSource="{Binding Items}">
+            <WrapPanel>
-                <ItemsRepeater.ItemTemplate>
+                <Button Command="{Binding SelectAll}" IsEnabled="{Binding !AreAllSelected}">Select All</Button>
-                    <DataTemplate>
+                <Button Command="{Binding SelectNone}" IsEnabled="{Binding !AreNoneSelected}">Select None</Button>
+            </WrapPanel>
+            <WrapPanel HorizontalAlignment="Right">
+                <Button Click="ClickOk">OK</Button>
+                <Button Click="ClickCancel">Cancel</Button>
+            </WrapPanel>
+        </Panel>
+        <ScrollViewer DockPanel.Dock="Top">
+            <TreeView Name="TreeView" Classes="noSelection" ItemsSource="{Binding RootItems}" ContainerPrepared="TreeViewOnContainerPrepared">
+                <TreeView.ItemTemplate>
+                    <TreeDataTemplate ItemsSource="{Binding Children}">
                         <CheckBox IsChecked="{Binding IsChecked}">
                             <Label>
                                 <TextBlock Text="{Binding Title}" TextWrapping="Wrap" />
                             </Label>
                         </CheckBox>
-                    </DataTemplate>
+                    </TreeDataTemplate>
-                </ItemsRepeater.ItemTemplate>
+                </TreeView.ItemTemplate>
-            </ItemsRepeater>
+            </TreeView>
         </ScrollViewer>
-        <Panel Classes="buttons">
+    </DockPanel>
-            <WrapPanel Classes="left">
-                <Button Command="{Binding SelectAll}" IsEnabled="{Binding !AreAllSelected}">Select All</Button>
-                <Button Command="{Binding SelectNone}" IsEnabled="{Binding !AreNoneSelected}">Select None</Button>
-            </WrapPanel>
-            <WrapPanel Classes="right">
-                <Button Click="ClickOk">OK</Button>
-                <Button Click="ClickCancel">Cancel</Button>
-            </WrapPanel>
-        </Panel>
-    </StackPanel>
 
 </Window>

app/Desktop/Dialogs/CheckBox/CheckBoxDialog.axaml.cs

@@ -1,6 +1,9 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
+using Avalonia.Controls.Primitives;
+using Avalonia.Input;
 using Avalonia.Interactivity;
+using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.Message;
 
 namespace DHT.Desktop.Dialogs.CheckBox;
@@ -11,6 +14,36 @@ public sealed partial class CheckBoxDialog : Window {
 		InitializeComponent();
 	}
 	
+	private void TreeViewOnContainerPrepared(object? sender, ContainerPreparedEventArgs e) {
+		foreach (object? item in TreeView.Items) {
+			if (item != null && TreeView.ContainerFromItem(item) is TreeViewItem treeViewItem) {
+				treeViewItem.TemplateApplied += TreeViewItemOnTemplateApplied;
+				treeViewItem.GotFocus += TreeViewItemOnGotFocus;
+				treeViewItem.KeyDown += TreeViewItemOnKeyDown;
+			}
+		}
+	}
+	
+	private void TreeViewItemOnTemplateApplied(object? sender, TemplateAppliedEventArgs e) {
+		if (sender is TreeViewItem { HeaderPresenter: Interactive headerPresenter } ) {
+			// Removes support for double-clicking to expand.
+			AvaloniaReflection.GetEventHandler(headerPresenter, DoubleTappedEvent)?.Clear();
+		}
+	}
+	
+	private void TreeViewItemOnGotFocus(object? sender, GotFocusEventArgs e) {
+		if (e.NavigationMethod == NavigationMethod.Tab && sender is TreeViewItem treeViewItem && TreeView.SelectedItem == null) {
+			TreeView.SelectedItem = TreeView.ItemFromContainer(treeViewItem);
+		}
+	}
+	
+	private void TreeViewItemOnKeyDown(object? sender, KeyEventArgs e) {
+		if (e.Key == Key.Space && TreeView.SelectedItem is ICheckBoxItem item) {
+			item.IsChecked = item.IsChecked == false;
+			e.Handled = true;
+		}
+	}
+	
 	public void ClickOk(object? sender, RoutedEventArgs e) {
 		Close(DialogResult.OkCancel.Ok);
 	}

app/Desktop/Dialogs/CheckBox/CheckBoxDialogModel.cs

@@ -1,70 +1,73 @@
-using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.ComponentModel;
 using System.Linq;
-using CommunityToolkit.Mvvm.ComponentModel;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Dialogs.CheckBox;
 
-class CheckBoxDialogModel : ObservableObject {
+partial class CheckBoxDialogModel {
 	public string Title { get; init; } = "";
 	
-	private IReadOnlyList<CheckBoxItem> items = Array.Empty<CheckBoxItem>();
+	private ImmutableArray<ICheckBoxItem> rootItems = [];
 	
-	public IReadOnlyList<CheckBoxItem> Items {
+	public ImmutableArray<ICheckBoxItem> RootItems {
-		get => items;
+		get => rootItems;
 		
 		protected set {
-			foreach (var item in items) {
+			foreach (ICheckBoxItem item in ICheckBoxItem.GetAllRecursively(rootItems)) {
 				item.PropertyChanged -= OnItemPropertyChanged;
 			}
 			
-			items = value;
+			rootItems = value;
 			
-			foreach (var item in items) {
+			foreach (ICheckBoxItem item in ICheckBoxItem.GetAllRecursively(rootItems)) {
 				item.PropertyChanged += OnItemPropertyChanged;
 			}
 		}
 	}
 	
-	private bool pauseCheckEvents = false;
+	protected IEnumerable<ICheckBoxItem> AllItems => ICheckBoxItem.GetAllRecursively(RootItems);
 	
-	public bool AreAllSelected => Items.All(static item => item.IsChecked);
+	[DependsOn(nameof(RootItems))]
-	public bool AreNoneSelected => Items.All(static item => !item.IsChecked);
+	public bool AreAllSelected => RootItems.All(static item => item.IsChecked == true);
+	
+	[DependsOn(nameof(RootItems))]
+	public bool AreNoneSelected => RootItems.All(static item => item.IsChecked == false);
+	
+	private bool pauseUpdatingBulkButtons = false;
 	
 	public void SelectAll() => SetAllChecked(true);
 	public void SelectNone() => SetAllChecked(false);
 	
 	private void SetAllChecked(bool isChecked) {
-		pauseCheckEvents = true;
+		pauseUpdatingBulkButtons = true;
 		
-		foreach (var item in Items) {
+		foreach (ICheckBoxItem item in RootItems) {
 			item.IsChecked = isChecked;
 		}
 		
-		pauseCheckEvents = false;
+		pauseUpdatingBulkButtons = false;
 		UpdateBulkButtons();
 	}
 	
-	private void UpdateBulkButtons() {
-		OnPropertyChanged(nameof(AreAllSelected));
-		OnPropertyChanged(nameof(AreNoneSelected));
-	}
-
 	private void OnItemPropertyChanged(object? sender, PropertyChangedEventArgs e) {
-		if (!pauseCheckEvents && e.PropertyName == nameof(CheckBoxItem.IsChecked)) {
+		if (e.PropertyName == nameof(ICheckBoxItem.IsChecked) && !pauseUpdatingBulkButtons) {
 			UpdateBulkButtons();
 		}
 	}
+	
+	private void UpdateBulkButtons() {
+		OnPropertyChanged(new PropertyChangedEventArgs(nameof(RootItems)));
+	}
 }
 
 sealed class CheckBoxDialogModel<T> : CheckBoxDialogModel {
-	private new IReadOnlyList<CheckBoxItem<T>> Items { get; }
+	public IEnumerable<T> SelectedValues => AllItems.OfType<ICheckBoxItem.Leaf<T>>()
+	                                                .Where(static item => item.IsChecked == true)
+	                                                .Select(static item => item.Value);
 	
-	public IEnumerable<CheckBoxItem<T>> SelectedItems => Items.Where(static item => item.IsChecked);
+	public CheckBoxDialogModel(ImmutableArray<ICheckBoxItem> items) {
-
+		this.RootItems = items;
-	public CheckBoxDialogModel(IEnumerable<CheckBoxItem<T>> items) {
-		this.Items = new List<CheckBoxItem<T>>(items);
-		base.Items = this.Items;
 	}
 }

app/Desktop/Dialogs/CheckBox/CheckBoxItem.cs

@@ -1,20 +1,110 @@
-using CommunityToolkit.Mvvm.ComponentModel;
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.ComponentModel;
+using System.Linq;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Dialogs.CheckBox;
 
-partial class CheckBoxItem : ObservableObject {
+partial interface ICheckBoxItem : INotifyPropertyChanged {
-	public string Title { get; init; } = "";
+	public string Title { get; }
-	public object? Item { get; init; } = null;
+	public bool? IsChecked { get; set; }
 	
-	[ObservableProperty]
+	public ImmutableArray<ICheckBoxItem> Children { get; }
-	private bool isChecked = false;
-}
 	
-sealed class CheckBoxItem<T> : CheckBoxItem {
+	void NotifyIsCheckedChanged();
-	public new T Item { get; }
 	
-	public CheckBoxItem(T item) {
+	public static IEnumerable<ICheckBoxItem> GetAllRecursively(IEnumerable<ICheckBoxItem> items) {
-		this.Item = item;
+		Stack<ICheckBoxItem> stack = new Stack<ICheckBoxItem>(items);
-		base.Item = item;
+		
+		while (stack.TryPop(out var item)) {
+			yield return item;
+			
+			foreach (ICheckBoxItem child in item.Children) {
+				stack.Push(child);
+			}
+		}
+	}
+	
+	sealed class NonLeaf : ICheckBoxItem {
+		public string Title { get; }
+		
+		public bool? IsChecked {
+			get {
+				if (Children.Count(static child => child.IsChecked == true) == Children.Length) {
+					return true;
+				}
+				else if (Children.Count(static child => child.IsChecked == false) == Children.Length) {
+					return false;
+				}
+				else {
+					return null;
+				}
+			}
+			
+			set {
+				foreach (ICheckBoxItem child in Children) {
+					if (child is Leaf leaf) {
+						leaf.SetCheckedFromParent(value);
+					}
+					else {
+						child.IsChecked = value;
+					}
+				}
+				
+				NotifyIsCheckedChanged();
+				parent?.NotifyIsCheckedChanged();
+			}
+		}
+		
+		public ImmutableArray<ICheckBoxItem> Children { get; }
+		
+		public event PropertyChangedEventHandler? PropertyChanged;
+		
+		private readonly ICheckBoxItem? parent;
+		
+		public NonLeaf(string title, ICheckBoxItem? parent, Func<ICheckBoxItem, ImmutableArray<ICheckBoxItem>> children) {
+			this.parent = parent;
+			this.Title = title;
+			this.Children = children(this);
+		}
+		
+		public void NotifyIsCheckedChanged() {
+			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(IsChecked)));
+		}
+	}
+	
+	partial class Leaf(string title, ICheckBoxItem? parent, bool isChecked) : ICheckBoxItem {
+		public string Title { get; } = title;
+		
+		public ImmutableArray<ICheckBoxItem> Children => ImmutableArray<ICheckBoxItem>.Empty;
+		
+		public readonly ICheckBoxItem? parent = parent;
+		
+		[Notify]
+		private bool? isChecked = isChecked;
+		
+		private bool notifyParent = true;
+		
+		public void SetCheckedFromParent(bool? isChecked) {
+			notifyParent = false;
+			IsChecked = isChecked;
+			notifyParent = true;
+		}
+		
+		private void OnIsCheckedChanged() {
+			if (notifyParent) {
+				parent?.NotifyIsCheckedChanged();
+			}
+		}
+		
+		void ICheckBoxItem.NotifyIsCheckedChanged() {
+			OnPropertyChanged(new PropertyChangedEventArgs(nameof(IsChecked)));
+		}
+	}
+	
+	sealed class Leaf<T>(string title, ICheckBoxItem? parent, T value, bool isChecked) : Leaf(title, parent, isChecked) {
+		public T Value => value;
 	}
 }

app/Desktop/Dialogs/CheckBox/CheckBoxItemList.cs

@@ -0,0 +1,46 @@
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Linq;
+
+namespace DHT.Desktop.Dialogs.CheckBox;
+
+sealed class CheckBoxItemList<TKey, TValue> where TKey : notnull {
+	private readonly List<INode> rootNodes = [];
+	private readonly Dictionary<TKey, List<INode>> parentNodes = [];
+	
+	public void AddParent(TKey key, string title) {
+		if (!parentNodes.ContainsKey(key)) {
+			List<INode> children = [];
+			rootNodes.Add(new INode.NonLeaf(title, children));
+			parentNodes[key] = children;
+		}
+	}
+	
+	public void Add(TValue value, string title, bool isChecked = false) {
+		rootNodes.Add(new INode.Leaf(title, value, isChecked));
+	}
+	
+	public void Add(TKey key, TValue value, string title, bool isChecked = false) {
+		parentNodes.GetValueOrDefault(key, rootNodes).Add(new INode.Leaf(title, value, isChecked));
+	}
+	
+	public ImmutableArray<ICheckBoxItem> ToCheckBoxItems() {
+		return [..rootNodes.Select(static node => node.ToCheckBoxItem(null))];
+	}
+	
+	private interface INode {
+		ICheckBoxItem ToCheckBoxItem(ICheckBoxItem? parent);
+		
+		sealed record NonLeaf(string Title, List<INode> Children) : INode {
+			public ICheckBoxItem ToCheckBoxItem(ICheckBoxItem? parent) {
+				return new ICheckBoxItem.NonLeaf(Title, parent, self => [..Children.Select(child => child.ToCheckBoxItem(self))]);
+			}
+		}
+		
+		sealed record Leaf(string Title, TValue Value, bool IsChecked) : INode {
+			public ICheckBoxItem ToCheckBoxItem(ICheckBoxItem? parent) {
+				return new ICheckBoxItem.Leaf<TValue>(Title, parent, Value, IsChecked);
+			}
+		}
+	}
+}

app/Desktop/Dialogs/File/FileDialogs.cs

@@ -8,6 +8,10 @@ using Avalonia.Platform.Storage;
 namespace DHT.Desktop.Dialogs.File;
 
 static class FileDialogs {
+	public static async Task<string[]> OpenFolders(this IStorageProvider storageProvider, FolderPickerOpenOptions options) {
+		return (await storageProvider.OpenFolderPickerAsync(options)).ToLocalPaths();
+	}
+	
 	public static async Task<string[]> OpenFiles(this IStorageProvider storageProvider, FilePickerOpenOptions options) {
 		return (await storageProvider.OpenFilePickerAsync(options)).ToLocalPaths();
 	}
@@ -18,7 +22,7 @@ static class FileDialogs {
 	
 	public static FilePickerFileType CreateFilter(string name, string[] extensions) {
 		return new FilePickerFileType(name) {
-			Patterns = extensions.Select(static ext => "*." + ext).ToArray()
+			Patterns = extensions.Select(static ext => "*." + ext).ToArray(),
 		};
 	}
 	
@@ -26,11 +30,11 @@ static class FileDialogs {
 		return suggestedDirectory == null ? Task.FromResult<IStorageFolder?>(null) : window.StorageProvider.TryGetFolderFromPathAsync(suggestedDirectory);
 	}
 	
-	private static string ToLocalPath(this IStorageFile file) {
+	private static string ToLocalPath(this IStorageItem itme) {
-		return file.TryGetLocalPath() ?? throw new NotSupportedException("Local filesystem is not supported.");
+		return itme.TryGetLocalPath() ?? throw new NotSupportedException("Local filesystem is not supported.");
 	}
 	
-	private static string[] ToLocalPaths(this IReadOnlyList<IStorageFile> files) {
+	private static string[] ToLocalPaths(this IReadOnlyList<IStorageItem> items) {
-		return files.Select(ToLocalPath).ToArray();
+		return items.Select(ToLocalPath).ToArray();
 	}
 }

app/Desktop/Dialogs/Message/Dialog.cs

@@ -15,8 +15,8 @@ static class Dialog {
 			DataContext = new MessageDialogModel {
 				Title = title,
 				Message = message,
-				IsOkVisible = true
+				IsOkVisible = true,
-			}
+			},
 		}.ShowDialog<DialogResult.All>(owner);
 	}
 	
@@ -30,8 +30,8 @@ static class Dialog {
 				Title = title,
 				Message = message,
 				IsOkVisible = true,
-				IsCancelVisible = true
+				IsCancelVisible = true,
-			}
+			},
 		}.ShowDialog<DialogResult.All?>(owner);
 		
 		return result.ToOkCancel();
@@ -47,8 +47,8 @@ static class Dialog {
 				Title = title,
 				Message = message,
 				IsYesVisible = true,
-				IsNoVisible = true
+				IsNoVisible = true,
-			}
+			},
 		}.ShowDialog<DialogResult.All?>(owner);
 		
 		return result.ToYesNo();
@@ -65,8 +65,8 @@ static class Dialog {
 				Message = message,
 				IsYesVisible = true,
 				IsNoVisible = true,
-				IsCancelVisible = true
+				IsCancelVisible = true,
-			}
+			},
 		}.ShowDialog<DialogResult.All?>(owner);
 		
 		return result.ToYesNoCancel();

app/Desktop/Dialogs/Message/DialogResult.cs

@@ -7,26 +7,26 @@ static class DialogResult {
 		Ok,
 		Yes,
 		No,
-		Cancel
+		Cancel,
 	}
 	
 	public enum OkCancel {
 		Closed,
 		Ok,
-		Cancel
+		Cancel,
 	}
 	
 	public enum YesNo {
 		Closed,
 		Yes,
-		No
+		No,
 	}
 	
 	public enum YesNoCancel {
 		Closed,
 		Yes,
 		No,
-		Cancel
+		Cancel,
 	}
 	
 	public static OkCancel ToOkCancel(this All? result) {
@@ -34,7 +34,7 @@ static class DialogResult {
 			null       => OkCancel.Closed,
 			All.Ok     => OkCancel.Ok,
 			All.Cancel => OkCancel.Cancel,
-			_          => throw new ArgumentException("Cannot convert dialog result " + result + " to ok/cancel.")
+			_          => throw new ArgumentException("Cannot convert dialog result " + result + " to ok/cancel."),
 		};
 	}
 	
@@ -43,7 +43,7 @@ static class DialogResult {
 			null    => YesNo.Closed,
 			All.Yes => YesNo.Yes,
 			All.No  => YesNo.No,
-			_       => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no.")
+			_       => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no."),
 		};
 	}
 	
@@ -53,7 +53,7 @@ static class DialogResult {
 			All.Yes    => YesNoCancel.Yes,
 			All.No     => YesNoCancel.No,
 			All.Cancel => YesNoCancel.Cancel,
-			_          => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no/cancel.")
+			_          => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no/cancel."),
 		};
 	}
 }

app/Desktop/Dialogs/Message/MessageDialog.axaml

@@ -20,24 +20,18 @@
             <Setter Property="FontSize" Value="15" />
             <Setter Property="TextWrapping" Value="Wrap" />
         </Style>
-        <Style Selector="WrapPanel">
-            <Setter Property="HorizontalAlignment" Value="Right" />
-            <Setter Property="Margin" Value="0 8 0 0" />
-        </Style>
-        <Style Selector="Button">
-            <Setter Property="Margin" Value="8 0 0 0" />
-            <Setter Property="MinWidth" Value="80" />
-        </Style>
     </Window.Styles>
 
     <StackPanel Margin="20">
         <TextBlock Text="{Binding Message}" />
-        <WrapPanel>
+        <Panel Classes="buttons">
+            <WrapPanel HorizontalAlignment="Right">
                 <Button Click="ClickOk" IsVisible="{Binding IsOkVisible}">OK</Button>
                 <Button Click="ClickYes" IsVisible="{Binding IsYesVisible}">Yes</Button>
                 <Button Click="ClickNo" IsVisible="{Binding IsNoVisible}">No</Button>
                 <Button Click="ClickCancel" IsVisible="{Binding IsCancelVisible}">Cancel</Button>
             </WrapPanel>
+        </Panel>
     </StackPanel>
 
 </Window>

app/Desktop/Dialogs/Progress/DelayedProgressDialog.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Threading.Tasks;
+using Avalonia.Controls;
+using Avalonia.Threading;
+
+namespace DHT.Desktop.Dialogs.Progress;
+
+static class DelayedProgressDialog {
+	public static async ValueTask Await(Func<Task> taskProvider, TimeSpan delay, Window window, string progressDialogTitle, string progressDialogDescription) {
+		Dispatcher.UIThread.VerifyAccess();
+		
+		Task task = Task.Run(taskProvider);
+		if (task.IsCompleted) {
+			return;
+		}
+		
+		// Freeze the UI thread for a short while in case the task finishes quickly.
+		_ = Task.WhenAny(Task.Delay(delay), task).GetAwaiter().GetResult();
+		
+		if (!task.IsCompleted) {
+			await ProgressDialog.ShowIndeterminate(window, progressDialogTitle, progressDialogDescription, _ => task);
+		}
+	}
+}

app/Desktop/Dialogs/Progress/IProgressCallback.cs

@@ -3,7 +3,7 @@ using System.Threading.Tasks;
 namespace DHT.Desktop.Dialogs.Progress;
 
 interface IProgressCallback {
-	Task Update(string message, int finishedItems, int totalItems);
+	Task Update(string message, long finishedItems, long totalItems);
 	Task UpdateIndeterminate(string message);
 	Task Hide();
 }

app/Desktop/Dialogs/Progress/ProgressDialog.axaml.cs

@@ -7,59 +7,42 @@ namespace DHT.Desktop.Dialogs.Progress;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
 public sealed partial class ProgressDialog : Window {
+	private static readonly TimeSpan MinimumShowDuration = TimeSpan.FromMilliseconds(500);
+	
 	internal static async Task Show(Window owner, string title, Func<ProgressDialog, IProgressCallback, Task> action) {
-		var taskCompletionSource = new TaskCompletionSource();
 		var dialog = new ProgressDialog();
-		
+		dialog.DataContext = new ProgressDialogModel(title, async callbacks => await action(dialog, callbacks[0]));
-		dialog.DataContext = new ProgressDialogModel(title, async callbacks => {
-			try {
-				await action(dialog, callbacks[0]);
-				taskCompletionSource.SetResult();
-			} catch (Exception e) {
-				taskCompletionSource.SetException(e);
-			}
-		});
-		
 		await dialog.ShowProgressDialog(owner);
-		await taskCompletionSource.Task;
 	}
 	
-	internal static async Task ShowIndeterminate(Window owner, string title, string message, Func<ProgressDialog, Task> action) {
+	internal static async Task<T> Show<T>(Window owner, string title, Func<ProgressDialog, IProgressCallback, Task<T>> action) {
-		var taskCompletionSource = new TaskCompletionSource();
-		var dialog = new ProgressDialog();
-		
-		dialog.DataContext = new ProgressDialogModel(title, async callbacks => {
-			await callbacks[0].UpdateIndeterminate(message);
-			try {
-				await action(dialog);
-				taskCompletionSource.SetResult();
-			} catch (Exception e) {
-				taskCompletionSource.SetException(e);
-			}
-		});
-		
-		await dialog.ShowProgressDialog(owner);
-		await taskCompletionSource.Task;
-	}
-	
-	internal static async Task<T> ShowIndeterminate<T>(Window owner, string title, string message, Func<ProgressDialog, Task<T>> action) {
 		var taskCompletionSource = new TaskCompletionSource<T>();
 		var dialog = new ProgressDialog();
 		
 		dialog.DataContext = new ProgressDialogModel(title, async callbacks => {
-			await callbacks[0].UpdateIndeterminate(message);
+			taskCompletionSource.SetResult(await action(dialog, callbacks[0]));
-			try {
-				taskCompletionSource.SetResult(await action(dialog));
-			} catch (Exception e) {
-				taskCompletionSource.SetException(e);
-			}
 		});
 		
 		await dialog.ShowProgressDialog(owner);
 		return await taskCompletionSource.Task;
 	}
 	
+	internal static Task ShowIndeterminate(Window owner, string title, string message, Func<ProgressDialog, Task> action) {
+		return Show(owner, title, async (dialog, callback) => {
+			await callback.UpdateIndeterminate(message);
+			await action(dialog);
+		});
+	}
+	
+	internal static Task<T> ShowIndeterminate<T>(Window owner, string title, string message, Func<ProgressDialog, Task<T>> action) {
+		return Show<T>(owner, title, async (dialog, callback) => {
+			await callback.UpdateIndeterminate(message);
+			return await action(dialog);
+		});
+	}
+	
 	private bool isFinished = false;
+	private DateTime startTime = DateTime.Now;
 	private Task progressTask = Task.CompletedTask;
 	
 	public ProgressDialog() {
@@ -67,6 +50,8 @@ public sealed partial class ProgressDialog : Window {
 	}
 	
 	public void OnOpened(object? sender, EventArgs e) {
+		startTime = DateTime.Now;
+		
 		if (DataContext is ProgressDialogModel model) {
 			progressTask = Task.Run(model.StartTask);
 			progressTask.ContinueWith(OnFinished, TaskScheduler.FromCurrentSynchronizationContext());
@@ -77,8 +62,14 @@ public sealed partial class ProgressDialog : Window {
 		e.Cancel = !isFinished;
 	}
 	
-	private void OnFinished(Task task) {
+	private async Task OnFinished(Task task) {
 		isFinished = true;
+		
+		TimeSpan elapsedTime = DateTime.Now - startTime;
+		if (elapsedTime < MinimumShowDuration) {
+			await Task.Delay(MinimumShowDuration - elapsedTime);
+		}
+		
 		Close();
 	}
 	

app/Desktop/Dialogs/Progress/ProgressDialogModel.cs

@@ -10,7 +10,7 @@ namespace DHT.Desktop.Dialogs.Progress;
 sealed class ProgressDialogModel {
 	public string Title { get; init; } = "";
 	
-	public IReadOnlyList<ProgressItem> Items { get; } = Array.Empty<ProgressItem>();
+	public IReadOnlyList<ProgressItem> Items { get; } = [];
 	
 	private readonly TaskRunner? task;
 	
@@ -20,7 +20,7 @@ sealed class ProgressDialogModel {
 	public ProgressDialogModel(string title, TaskRunner task, int progressItems = 1) {
 		this.Title = title;
 		this.task = task;
-		this.Items = Enumerable.Range(0, progressItems).Select(static _ => new ProgressItem()).ToArray();
+		this.Items = Enumerable.Range(start: 0, progressItems).Select(static _ => new ProgressItem()).ToArray();
 	}
 	
 	internal async Task StartTask() {
@@ -38,7 +38,7 @@ sealed class ProgressDialogModel {
 			this.item = item;
 		}
 		
-		public async Task Update(string message, int finishedItems, int totalItems) {
+		public async Task Update(string message, long finishedItems, long totalItems) {
 			await Dispatcher.UIThread.InvokeAsync(() => {
 				item.Message = message;
 				item.Items = totalItems == 0 ? string.Empty : finishedItems.Format() + " / " + totalItems.Format();
@@ -57,7 +57,7 @@ sealed class ProgressDialogModel {
 		}
 		
 		public Task Hide() {
-			return Update(string.Empty, 0, 0);
+			return Update(string.Empty, finishedItems: 0, totalItems: 0);
 		}
 	}
 }

app/Desktop/Dialogs/Progress/ProgressItem.cs

@@ -1,30 +1,23 @@
-using CommunityToolkit.Mvvm.ComponentModel;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Dialogs.Progress;
 
-sealed partial class ProgressItem : ObservableObject {
+sealed partial class ProgressItem {
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify]
-	[NotifyPropertyChangedFor(nameof(Opacity))]
-	private bool isVisible = false;
-
-	public double Opacity => IsVisible ? 1.0 : 0.0;
-
 	private string message = "";
 	
-	public string Message {
+	[Notify]
-		get => message;
-		set {
-			SetProperty(ref message, value);
-			IsVisible = !string.IsNullOrEmpty(value);
-		}
-	}
-
-	[ObservableProperty]
 	private string items = "";
 	
-	[ObservableProperty]
+	[Notify]
-	private int progress = 0;
+	private long progress = 0L;
 	
-	[ObservableProperty]
+	[Notify]
 	private bool isIndeterminate;
+	
+	[DependsOn(nameof(Message))]
+	public bool IsVisible => !string.IsNullOrEmpty(Message);
+	
+	[DependsOn(nameof(IsVisible))]
+	public double Opacity => IsVisible ? 1.0 : 0.0;
 }

app/Desktop/Dialogs/TextBox/TextBoxDialog.axaml

@@ -15,19 +15,6 @@
         <namespace:TextBoxDialogModel />
     </Window.DataContext>
 
-    <Window.Styles>
-        <Style Selector="Panel.buttons">
-            <Setter Property="Margin" Value="0 20 0 0" />
-        </Style>
-        <Style Selector="Panel.buttons > WrapPanel.right">
-            <Setter Property="HorizontalAlignment" Value="Right" />
-        </Style>
-        <Style Selector="Panel.buttons Button">
-            <Setter Property="MinWidth" Value="80" />
-            <Setter Property="Margin" Value="8 0 0 0" />
-        </Style>
-    </Window.Styles>
-
     <StackPanel Margin="20">
         <ScrollViewer MaxHeight="400">
             <StackPanel Spacing="10">
@@ -47,7 +34,7 @@
             </StackPanel>
         </ScrollViewer>
         <Panel Classes="buttons">
-            <WrapPanel Classes="right">
+            <WrapPanel HorizontalAlignment="Right">
                 <Button Click="ClickOk" IsEnabled="{Binding !HasErrors}">OK</Button>
                 <Button Click="ClickCancel">Cancel</Button>
             </WrapPanel>

app/Desktop/Dialogs/TextBox/TextBoxDialogModel.cs

@@ -1,37 +1,37 @@
-using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
-using CommunityToolkit.Mvvm.ComponentModel;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Dialogs.TextBox;
 
-class TextBoxDialogModel : ObservableObject {
+partial class TextBoxDialogModel {
 	public string Title { get; init; } = "";
 	public string Description { get; init; } = "";
 	
-	private IReadOnlyList<TextBoxItem> items = Array.Empty<TextBoxItem>();
+	private IReadOnlyList<TextBoxItem> items = [];
 	
 	public IReadOnlyList<TextBoxItem> Items {
 		get => items;
 		
 		protected set {
-			foreach (var item in items) {
+			foreach (TextBoxItem item in items) {
 				item.ErrorsChanged -= OnItemErrorsChanged;
 			}
 			
 			items = value;
 			
-			foreach (var item in items) {
+			foreach (TextBoxItem item in items) {
 				item.ErrorsChanged += OnItemErrorsChanged;
 			}
 		}
 	}
 	
+	[DependsOn(nameof(Items))]
 	public bool HasErrors => Items.Any(static item => !item.IsValid);
 	
 	private void OnItemErrorsChanged(object? sender, DataErrorsChangedEventArgs e) {
-		OnPropertyChanged(nameof(HasErrors));
+		OnPropertyChanged(new PropertyChangedEventArgs(nameof(Items)));
 	}
 }
 

app/Desktop/Dialogs/TextBox/TextBoxItem.cs

@@ -1,26 +1,23 @@
 using System;
 using System.Collections;
 using System.ComponentModel;
-using CommunityToolkit.Mvvm.ComponentModel;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Dialogs.TextBox;
 
-class TextBoxItem : ObservableObject, INotifyDataErrorInfo {
+partial class TextBoxItem : INotifyDataErrorInfo {
 	public string Title { get; init; } = "";
 	public object? Item { get; init; } = null;
 	
 	public Func<string, bool> ValidityCheck { get; init; } = static _ => true;
 	public bool IsValid => ValidityCheck(Value);
 	
+	[Notify]
 	private string value = string.Empty;
 	
-	public string Value {
+	private void OnValueChanged() {
-		get => this.value;
-		set {
-			SetProperty(ref this.value, value);
 		ErrorsChanged?.Invoke(this, new DataErrorsChangedEventArgs(nameof(Value)));
 	}
-	}
 	
 	public IEnumerable GetErrors(string? propertyName) {
 		if (propertyName == nameof(Value) && !IsValid) {

app/Desktop/Discord/DiscordAppSettings.cs

@@ -39,17 +39,16 @@ static class DiscordAppSettings {
 	
 	public static async Task<bool?> AreDevToolsEnabled() {
 		try {
-			var settingsJson = await ReadSettingsJson();
+			JsonObject settingsJson = await ReadSettingsJson();
 			return AreDevToolsEnabled(settingsJson);
 		} catch (Exception e) {
-			Log.Error("Cannot read settings file.");
+			Log.Error("Could not read settings file.", e);
-			Log.Error(e);
 			return null;
 		}
 	}
 	
 	private static bool AreDevToolsEnabled(JsonObject json) {
-		return json.TryGetPropertyValue(JsonKeyDevTools, out var node) && node?.GetValueKind() == JsonValueKind.True;
+		return json.TryGetPropertyValue(JsonKeyDevTools, out JsonNode? node) && node?.GetValueKind() == JsonValueKind.True;
 	}
 	
 	public static async Task<SettingsJsonResult> ConfigureDevTools(bool enable) {
@@ -62,7 +61,7 @@ static class DiscordAppSettings {
 		} catch (JsonException) {
 			return SettingsJsonResult.InvalidJson;
 		} catch (Exception e) {
-			Log.Error(e);
+			Log.Error("Could not read settings file.", e);
 			return SettingsJsonResult.ReadError;
 		}
 		
@@ -84,16 +83,14 @@ static class DiscordAppSettings {
 			
 			await WriteSettingsJson(json);
 		} catch (Exception e) {
-			Log.Error("An error occurred when writing settings file.");
+			Log.Error("Could not write settings file.", e);
-			Log.Error(e);
 			
 			if (File.Exists(JsonBackupFilePath)) {
 				try {
-					File.Move(JsonBackupFilePath, JsonFilePath, true);
+					File.Move(JsonBackupFilePath, JsonFilePath, overwrite: true);
 					Log.Info("Restored settings file from backup.");
 				} catch (Exception e2) {
-					Log.Error("Cannot restore settings file from backup.");
+					Log.Error("Could not restore settings file from backup.", e2);
-					Log.Error(e2);
 				}
 			}
 			
@@ -103,8 +100,7 @@ static class DiscordAppSettings {
 		try {
 			File.Delete(JsonBackupFilePath);
 		} catch (Exception e) {
-			Log.Error("Cannot delete backup file.");
+			Log.Error("Could not delete backup file.", e);
-			Log.Error(e);
 		}
 		
 		return SettingsJsonResult.Success;

app/Desktop/Discord/SettingsJsonResult.cs

@@ -6,5 +6,5 @@ enum SettingsJsonResult {
 	FileNotFound,
 	ReadError,
 	InvalidJson,
-	WriteError
+	WriteError,
 }

app/Desktop/Main/AboutWindow.axaml

@@ -3,12 +3,12 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:main="clr-namespace:DHT.Desktop.Main"
-        mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="295"
+        mc:Ignorable="d" d:DesignWidth="510" d:DesignHeight="425"
         x:Class="DHT.Desktop.Main.AboutWindow"
         x:DataType="main:AboutWindowModel"
         Title="About Discord History Tracker"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
-        Width="480" Height="295" CanResize="False"
+        Width="510" Height="425" CanResize="False"
         WindowStartupLocation="CenterOwner">
 
     <Design.DataContext>
@@ -16,16 +16,12 @@
     </Design.DataContext>
 
     <Window.Styles>
-        <Style Selector="StackPanel">
-            <Setter Property="Orientation" Value="Horizontal" />
-            <Setter Property="Spacing" Value="5" />
-        </Style>
         <Style Selector="TextBlock">
             <Setter Property="TextWrapping" Value="Wrap" />
             <Setter Property="VerticalAlignment" Value="Center" />
         </Style>
         <Style Selector="Grid > Button">
-            <Setter Property="Margin" Value="0 4" />
+            <Setter Property="Margin" Value="0 3" />
             <Setter Property="Padding" Value="8 4" />
             <Setter Property="HorizontalAlignment" Value="Stretch" />
         </Style>
@@ -33,35 +29,55 @@
 
     <StackPanel Orientation="Vertical" Margin="20" Spacing="12">
 
-        <TextBlock VerticalAlignment="Center">
+        <StackPanel Orientation="Vertical" Spacing="3">
-            Discord History Tracker was created by chylex and released under the MIT license.
+            <TextBlock TextWrapping="Wrap">Discord History Tracker was created by chylex.</TextBlock>
-        </TextBlock>
+            <TextBlock>It is available under the MIT license.</TextBlock>
-
-        <StackPanel>
-            <Button Command="{Binding ShowOfficialWebsite}">Official Website</Button>
-            <Button Command="{Binding ShowSourceCode}">Source Code</Button>
         </StackPanel>
 
-        <Grid RowDefinitions="Auto,5,Auto,Auto,Auto,Auto,Auto,Auto" ColumnDefinitions="175,125,*" Margin="0 10 0 0">
+        <StackPanel Orientation="Horizontal" Spacing="8">
+            <Button Command="{Binding OpenOfficialWebsite}">Official Website</Button>
+            <Button Command="{Binding OpenIssueTracker}">Issue Tracker</Button>
+            <Button Command="{Binding OpenSourceCode}">Source Code</Button>
+        </StackPanel>
+
+        <Grid RowDefinitions="Auto,5,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto" ColumnDefinitions="*,115,90" Margin="0 10 0 0">
             <TextBlock Grid.Row="0" Grid.Column="0" FontWeight="Bold">Third-Party Software</TextBlock>
             <TextBlock Grid.Row="0" Grid.Column="1" FontWeight="Bold">License</TextBlock>
             <TextBlock Grid.Row="0" Grid.Column="2" FontWeight="Bold">Link</TextBlock>
 
-            <TextBlock Grid.Row="2" Grid.Column="0">.NET 8</TextBlock>
+            <TextBlock Grid.Row="2" Grid.Column="0">.NET</TextBlock>
             <TextBlock Grid.Row="2" Grid.Column="1">MIT</TextBlock>
-            <Button Grid.Row="2" Grid.Column="2" Command="{Binding ShowLibraryNetCore}">GitHub</Button>
+            <Button Grid.Row="2" Grid.Column="2" Command="{Binding OpenThirdPartyNetCore}">GitHub</Button>
 
             <TextBlock Grid.Row="3" Grid.Column="0">Avalonia</TextBlock>
             <TextBlock Grid.Row="3" Grid.Column="1">MIT</TextBlock>
-            <Button Grid.Row="3" Grid.Column="2" Command="{Binding ShowLibraryAvalonia}">NuGet</Button>
+            <Button Grid.Row="3" Grid.Column="2" Command="{Binding OpenThirdPartyAvalonia}">GitHub</Button>
 
-            <TextBlock Grid.Row="4" Grid.Column="0">SQLite</TextBlock>
+            <TextBlock Grid.Row="4" Grid.Column="0">Rx.NET</TextBlock>
-            <TextBlock Grid.Row="4" Grid.Column="1">Public Domain</TextBlock>
+            <TextBlock Grid.Row="4" Grid.Column="1">MIT</TextBlock>
-            <Button Grid.Row="4" Grid.Column="2" Command="{Binding ShowLibrarySqlite}">Official Website</Button>
+            <Button Grid.Row="4" Grid.Column="2" Command="{Binding OpenThirdPartyRxNet}">GitHub</Button>
 
-            <TextBlock Grid.Row="5" Grid.Column="0">Microsoft.Data.Sqlite</TextBlock>
+            <TextBlock Grid.Row="5" Grid.Column="0">SQLite</TextBlock>
-            <TextBlock Grid.Row="5" Grid.Column="1">Apache-2.0</TextBlock>
+            <TextBlock Grid.Row="5" Grid.Column="1">Public Domain</TextBlock>
-            <Button Grid.Row="5" Grid.Column="2" Command="{Binding ShowLibrarySqliteAdoNet}">NuGet</Button>
+            <Button Grid.Row="5" Grid.Column="2" Command="{Binding OpenThirdPartySqlite}">Website</Button>
+
+            <TextBlock Grid.Row="6" Grid.Column="0">Microsoft.Data.Sqlite</TextBlock>
+            <TextBlock Grid.Row="6" Grid.Column="1">Apache-2.0</TextBlock>
+            <Button Grid.Row="6" Grid.Column="2" Command="{Binding OpenThirdPartyMicrosoftDataSqlite}">NuGet</Button>
+
+            <TextBlock Grid.Row="7" Grid.Column="0">PropertyChanged.SourceGenerator</TextBlock>
+            <TextBlock Grid.Row="7" Grid.Column="1">MIT</TextBlock>
+            <Button Grid.Row="7" Grid.Column="2" Command="{Binding OpenThirdPartyPropertyChangedSourceGenerator}">GitHub</Button>
+        </Grid>
+
+        <Grid RowDefinitions="Auto,5,Auto,Auto,Auto,Auto,Auto,Auto,Auto,Auto" ColumnDefinitions="*,115,90" Margin="0 5 0 0">
+            <TextBlock Grid.Row="0" Grid.Column="0" FontWeight="Bold">Additional Thanks</TextBlock>
+            <TextBlock Grid.Row="0" Grid.Column="1" FontWeight="Bold">License</TextBlock>
+            <TextBlock Grid.Row="0" Grid.Column="2" FontWeight="Bold">Link</TextBlock>
+
+            <TextBlock Grid.Row="2" Grid.Column="0">BetterDiscord, for Webpack hooks</TextBlock>
+            <TextBlock Grid.Row="2" Grid.Column="1">Apache-2.0</TextBlock>
+            <Button Grid.Row="2" Grid.Column="2" Command="{Binding OpenThirdPartyBetterDiscord}">GitHub</Button>
         </Grid>
 
     </StackPanel>

app/Desktop/Main/AboutWindowModel.cs

@@ -1,33 +1,45 @@
-using System.Diagnostics;
+using DHT.Desktop.Common;
 
 namespace DHT.Desktop.Main;
 
 sealed class AboutWindowModel {
-	public void ShowOfficialWebsite() {
+	public void OpenOfficialWebsite() {
-		OpenUrl("https://dht.chylex.com");
+		SystemUtils.OpenUrl(Program.Website);
 	}
 	
-	public void ShowSourceCode() {
+	public void OpenIssueTracker() {
-		OpenUrl("https://github.com/chylex/Discord-History-Tracker");
+		SystemUtils.OpenUrl("https://github.com/chylex/Discord-History-Tracker/issues");
 	}
 	
-	public void ShowLibraryAvalonia() {
+	public void OpenSourceCode() {
-		OpenUrl("https://www.nuget.org/packages/Avalonia");
+		SystemUtils.OpenUrl("https://github.com/chylex/Discord-History-Tracker");
 	}
 	
-	public void ShowLibrarySqlite() {
+	public void OpenThirdPartyNetCore() {
-		OpenUrl("https://www.sqlite.org");
+		SystemUtils.OpenUrl("https://github.com/dotnet/core");
 	}
 	
-	public void ShowLibrarySqliteAdoNet() {
+	public void OpenThirdPartyAvalonia() {
-		OpenUrl("https://www.nuget.org/packages/Microsoft.Data.Sqlite");
+		SystemUtils.OpenUrl("https://github.com/AvaloniaUI/Avalonia");
 	}
 	
-	public void ShowLibraryNetCore() {
+	public void OpenThirdPartyPropertyChangedSourceGenerator() {
-		OpenUrl("https://github.com/dotnet/core");
+		SystemUtils.OpenUrl("https://github.com/canton7/PropertyChanged.SourceGenerator");
 	}
 	
-	private static void OpenUrl(string url) {
+	public void OpenThirdPartySqlite() {
-		Process.Start(new ProcessStartInfo { FileName = url, UseShellExecute = true });
+		SystemUtils.OpenUrl("https://www.sqlite.org");
+	}
+	
+	public void OpenThirdPartyMicrosoftDataSqlite() {
+		SystemUtils.OpenUrl("https://www.nuget.org/packages/Microsoft.Data.Sqlite");
+	}
+	
+	public void OpenThirdPartyRxNet() {
+		SystemUtils.OpenUrl("https://github.com/dotnet/reactive");
+	}
+	
+	public void OpenThirdPartyBetterDiscord() {
+		SystemUtils.OpenUrl("https://github.com/BetterDiscord/BetterDiscord");
 	}
 }

app/Desktop/Main/Controls/DownloadItemFilterPanel.axaml

@@ -13,12 +13,8 @@
 
     <UserControl.Styles>
         <Style Selector="WrapPanel > StackPanel">
-            <Setter Property="Margin" Value="0 20 40 0" />
             <Setter Property="Spacing" Value="4" />
         </Style>
-        <Style Selector="WrapPanel > StackPanel:nth-last-child(1)">
-            <Setter Property="Margin" Value="0 20 0 0" />
-        </Style>
         <Style Selector="Grid > Label">
             <Setter Property="VerticalAlignment" Value="Center" />
         </Style>
@@ -30,9 +26,9 @@
         </Style>
     </UserControl.Styles>
 
-    <StackPanel>
+    <StackPanel Spacing="20">
         <TextBlock Text="{Binding FilterStatisticsText}" />
-        <WrapPanel>
+        <WrapPanel ItemSpacing="40" LineSpacing="20">
             <StackPanel>
                 <CheckBox IsChecked="{Binding LimitSize}">Limit Size</CheckBox>
                 <StackPanel Orientation="Horizontal">

app/Desktop/Main/Controls/DownloadItemFilterPanelModel.cs

@@ -2,45 +2,44 @@ using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
-using System.Reactive.Linq;
 using System.Threading.Tasks;
-using Avalonia.ReactiveUI;
-using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
 using DHT.Server;
 using DHT.Server.Data.Filters;
 using DHT.Server.Data.Settings;
 using DHT.Utils.Logging;
 using DHT.Utils.Tasks;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Controls;
 
-sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisposable {
+sealed partial class DownloadItemFilterPanelModel : IAsyncDisposable {
 	private static readonly Log Log = Log.ForType<DownloadItemFilterPanelModel>();
 	
 	public sealed record Unit(string Name, uint Scale);
 	
 	private static readonly Unit[] AllUnits = [
-		new Unit("B", 1),
+		new Unit("B", Scale: 1),
-		new Unit("kB", 1024),
+		new Unit("kB", Scale: 1024),
-		new Unit("MB", 1024 * 1024)
+		new Unit("MB", Scale: 1024 * 1024)
 	];
 	
 	private static readonly HashSet<string> FilterProperties = [
 		nameof(LimitSize),
 		nameof(MaximumSize),
-		nameof(MaximumSizeUnit)
+		nameof(MaximumSizeUnit),
 	];
 	
-	public string FilterStatisticsText { get; private set; } = "";
+	[Notify(Setter.Private)]
+	private string filterStatisticsText = "";
 	
-	[ObservableProperty]
+	[Notify]
 	private bool limitSize = false;
 	
-	[ObservableProperty]
+	[Notify]
 	private ulong maximumSize = 0UL;
 	
-	[ObservableProperty]
+	[Notify]
 	private Unit maximumSizeUnit = AllUnits[0];
 	
 	public IEnumerable<Unit> Units => AllUnits;
@@ -48,7 +47,7 @@ sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisp
 	private readonly State state;
 	private readonly string verb;
 	
-	private readonly DelayedThrottledTask<FilterSettings> saveFilterSettingsTask;
+	private readonly ThrottledTask<FilterSettings> saveFilterSettingsTask;
 	private bool isLoadingFilterSettings;
 	
 	private readonly RestartableTask<long> downloadItemCountTask;
@@ -64,10 +63,10 @@ sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisp
 		this.state = state;
 		this.verb = verb;
 		
-		this.saveFilterSettingsTask = new DelayedThrottledTask<FilterSettings>(Log, TimeSpan.FromSeconds(5), SaveFilterSettings);
+		this.saveFilterSettingsTask = new ThrottledTask<FilterSettings>(Log, SaveFilterSettings, TimeSpan.FromSeconds(5), TaskScheduler.Default);
 		
 		this.downloadItemCountTask = new RestartableTask<long>(SetMatchingCount, TaskScheduler.FromCurrentSynchronizationContext());
-		this.downloadItemCountSubscription = state.Db.Downloads.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnDownloadItemCountChanged);
+		this.downloadItemCountSubscription = state.Db.Downloads.TotalCount.SubscribeLastOnUI(OnDownloadItemCountChanged, TimeSpan.FromMilliseconds(15));
 		
 		UpdateFilterStatistics();
 		
@@ -80,7 +79,7 @@ sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisp
 		LimitSize = await state.Db.Settings.Get(SettingsKey.DownloadsLimitSize, LimitSize);
 		MaximumSize = await state.Db.Settings.Get(SettingsKey.DownloadsMaximumSize, MaximumSize);
 		
-		if (await state.Db.Settings.Get(SettingsKey.DownloadsMaximumSizeUnit, null) is {} unitName && AllUnits.FirstOrDefault(unit => unit.Name == unitName) is {} unitValue) {
+		if (await state.Db.Settings.Get(SettingsKey.DownloadsMaximumSizeUnit, defaultValue: null) is {} unitName && AllUnits.FirstOrDefault(unit => unit.Name == unitName) is {} unitValue) {
 			MaximumSizeUnit = unitValue;
 		}
 		
@@ -108,8 +107,7 @@ sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisp
 				await setter.Set(SettingsKey.DownloadsMaximumSizeUnit, settings.MaximumSizeUnit.Name);
 			});
 		} catch (Exception e) {
-			Log.Error("Could not save download filter settings");
+			Log.Error("Could not save download filter settings.", e);
-			Log.Error(e);
 		}
 	}
 	
@@ -130,7 +128,7 @@ sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisp
 	
 	
 	private void UpdateFilterStatistics() {
-		var filter = CreateFilter();
+		DownloadItemFilter filter = CreateFilter();
 		if (filter.IsEmpty) {
 			downloadItemCountTask.Cancel();
 			matchingItemCount = totalItemCount;
@@ -149,11 +147,9 @@ sealed partial class DownloadItemFilterPanelModel : ObservableObject, IAsyncDisp
 	}
 	
 	private void UpdateFilterStatisticsText() {
-		var matchingItemCountStr = matchingItemCount?.Format() ?? "(...)";
+		string matchingItemCountStr = matchingItemCount?.Format() ?? "(...)";
-		var totalItemCountStr = totalItemCount?.Format() ?? "(...)";
+		string totalItemCountStr = totalItemCount?.Format() ?? "(...)";
-
 		FilterStatisticsText = verb + " " + matchingItemCountStr + " out of " + totalItemCountStr + " file" + (totalItemCount is null or 1 ? "." : "s.");
-		OnPropertyChanged(nameof(FilterStatisticsText));
 	}
 	
 	public DownloadItemFilter CreateFilter() {

app/Desktop/Main/Controls/MessageFilterPanel.axaml

@@ -13,12 +13,8 @@
 
     <UserControl.Styles>
         <Style Selector="WrapPanel > StackPanel">
-            <Setter Property="Margin" Value="0 20 40 0" />
             <Setter Property="Spacing" Value="4" />
         </Style>
-        <Style Selector="WrapPanel > StackPanel:nth-last-child(1)">
-            <Setter Property="Margin" Value="0 20 0 0" />
-        </Style>
         <Style Selector="Grid > Label">
             <Setter Property="VerticalAlignment" Value="Center" />
         </Style>
@@ -36,9 +32,9 @@
         </Style>
     </UserControl.Styles>
 
-    <StackPanel>
+    <StackPanel Spacing="20">
         <TextBlock Text="{Binding FilterStatisticsText}" />
-        <WrapPanel>
+        <WrapPanel ItemSpacing="40" LineSpacing="20">
             <StackPanel>
                 <CheckBox IsChecked="{Binding FilterByDate}">Filter by Date</CheckBox>
                 <Grid ColumnDefinitions="Auto, 4, 125" RowDefinitions="Auto, 4, Auto" Margin="4 0">

app/Desktop/Main/Controls/MessageFilterPanel.axaml.cs

@@ -1,4 +1,5 @@
 using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
 using Avalonia.Controls;
 
 namespace DHT.Desktop.Main.Controls;
@@ -8,8 +9,8 @@ public sealed partial class MessageFilterPanel : UserControl {
 	public MessageFilterPanel() {
 		InitializeComponent();
 		
-		var culture = Program.Culture;
+		CultureInfo culture = Program.Culture;
-		foreach (var picker in new CalendarDatePicker[] { StartDatePicker, EndDatePicker }) {
+		foreach (CalendarDatePicker picker in new CalendarDatePicker[] { StartDatePicker, EndDatePicker }) {
 			picker.FirstDayOfWeek = culture.DateTimeFormat.FirstDayOfWeek;
 			picker.SelectedDateFormat = CalendarDatePickerFormat.Custom;
 			picker.CustomDateFormatString = culture.DateTimeFormat.ShortDatePattern;

app/Desktop/Main/Controls/MessageFilterPanelModel.cs

@@ -1,13 +1,11 @@
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.ComponentModel;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
-using System.Reactive.Linq;
-using System.Text;
 using System.Threading.Tasks;
 using Avalonia.Controls;
-using Avalonia.ReactiveUI;
-using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.CheckBox;
 using DHT.Desktop.Dialogs.Message;
@@ -16,10 +14,11 @@ using DHT.Server;
 using DHT.Server.Data;
 using DHT.Server.Data.Filters;
 using DHT.Utils.Tasks;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Controls;
 
-sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
+sealed partial class MessageFilterPanelModel : IDisposable {
 	private static readonly HashSet<string> FilterProperties = [
 		nameof(FilterByDate),
 		nameof(StartDate),
@@ -27,40 +26,41 @@ sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
 		nameof(FilterByChannel),
 		nameof(IncludedChannels),
 		nameof(FilterByUser),
-		nameof(IncludedUsers)
+		nameof(IncludedUsers),
 	];
 	
-	public string FilterStatisticsText { get; private set; } = "";
-
 	public event PropertyChangedEventHandler? FilterPropertyChanged;
 	
 	public bool HasAnyFilters => FilterByDate || FilterByChannel || FilterByUser;
 	
-	[ObservableProperty]
+	[Notify]
+	private string filterStatisticsText = "";
+	
+	[Notify]
 	private bool filterByDate = false;
 	
-	[ObservableProperty]
+	[Notify]
 	private DateTime? startDate = null;
 	
-	[ObservableProperty]
+	[Notify]
 	private DateTime? endDate = null;
 	
-	[ObservableProperty]
+	[Notify]
 	private bool filterByChannel = false;
 	
-	[ObservableProperty]
+	[Notify]
 	private HashSet<ulong>? includedChannels = null;
 	
-	[ObservableProperty]
+	[Notify]
 	private bool filterByUser = false;
 	
-	[ObservableProperty]
+	[Notify]
 	private HashSet<ulong>? includedUsers = null;
 	
-	[ObservableProperty]
+	[Notify]
 	private string channelFilterLabel = "";
 	
-	[ObservableProperty]
+	[Notify]
 	private string userFilterLabel = "";
 	
 	private readonly Window window;
@@ -89,9 +89,9 @@ sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
 		
 		this.exportedMessageCountTask = new RestartableTask<long>(SetExportedMessageCount, TaskScheduler.FromCurrentSynchronizationContext());
 		
-		this.messageCountSubscription = state.Db.Messages.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnMessageCountChanged);
+		this.messageCountSubscription = state.Db.Messages.TotalCount.SubscribeLastOnUI(OnMessageCountChanged, TimeSpan.FromMilliseconds(15));
-		this.channelCountSubscription = state.Db.Channels.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnChannelCountChanged);
+		this.channelCountSubscription = state.Db.Channels.TotalCount.SubscribeLastOnUI(OnChannelCountChanged, TimeSpan.FromMilliseconds(15));
-		this.userCountSubscription = state.Db.Users.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnUserCountChanged);
+		this.userCountSubscription = state.Db.Users.TotalCount.SubscribeLastOnUI(OnUserCountChanged, TimeSpan.FromMilliseconds(15));
 		
 		UpdateFilterStatistics();
 		UpdateChannelFilterLabel();
@@ -160,7 +160,7 @@ sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
 	}
 	
 	private void UpdateFilterStatistics() {
-		var filter = CreateFilter();
+		MessageFilter filter = CreateFilter();
 		if (filter.IsEmpty) {
 			exportedMessageCountTask.Cancel();
 			exportedMessageCount = totalMessageCount;
@@ -179,58 +179,69 @@ sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
 	}
 	
 	private void UpdateFilterStatisticsText() {
-		var exportedMessageCountStr = exportedMessageCount?.Format() ?? "(...)";
+		string exportedMessageCountStr = exportedMessageCount?.Format() ?? "(...)";
-		var totalMessageCountStr = totalMessageCount?.Format() ?? "(...)";
+		string totalMessageCountStr = totalMessageCount?.Format() ?? "(...)";
-
 		FilterStatisticsText = verb + " " + exportedMessageCountStr + " out of " + totalMessageCountStr + " message" + (totalMessageCount is null or 1 ? "." : "s.");
-		OnPropertyChanged(nameof(FilterStatisticsText));
+	}
+	
+	[SuppressMessage("ReSharper", "NotAccessedPositionalProperty.Local")]
+	[SuppressMessage("ReSharper", "MemberCanBePrivate.Local")]
+	private readonly record struct ChannelFilterKey(byte Type, ulong? ServerId, string Title) : IComparable<ChannelFilterKey> {
+		public static ChannelFilterKey DirectMessages { get; } = new (Type: 1, ServerId: null, Title: "Direct Messages");
+		public static ChannelFilterKey GroupMessages { get; } = new (Type: 2, ServerId: null, Title: "Group Messages");
+		public static ChannelFilterKey Unknown { get; } = new (Type: 4, ServerId: null, Title: "Unknown");
+		
+		public static ChannelFilterKey For(DHT.Server.Data.Server server) {
+			return server.Type switch {
+				ServerType.Server        => new ChannelFilterKey(Type: 3, server.Id, "Server - " + server.Name),
+				ServerType.Group         => GroupMessages,
+				ServerType.DirectMessage => DirectMessages,
+				_                        => Unknown,
+			};
+		}
+		
+		public bool Equals(ChannelFilterKey other) {
+			return Type == other.Type && ServerId == other.ServerId;
+		}
+		
+		public override int GetHashCode() {
+			return HashCode.Combine(Type, ServerId);
+		}
+		
+		public int CompareTo(ChannelFilterKey other) {
+			int result = Type.CompareTo(other.Type);
+			if (result != 0) {
+				return result;
+			}
+			else {
+				return Title.CompareTo(other.Title);
+			}
+		}
 	}
 	
 	public async Task OpenChannelFilterDialog() {
-		async Task<List<CheckBoxItem<ulong>>> PrepareChannelItems(ProgressDialog dialog) {
+		async Task<ImmutableArray<ICheckBoxItem>> PrepareChannelItems(ProgressDialog dialog) {
-			var items = new List<CheckBoxItem<ulong>>();
+			CheckBoxItemList<ChannelFilterKey, ulong> items = new CheckBoxItemList<ChannelFilterKey, ulong>();
-			var servers = await state.Db.Servers.Get().ToDictionaryAsync(static server => server.Id);
+			Dictionary<ulong, DHT.Server.Data.Server> servers = await state.Db.Servers.Get().ToDictionaryAsync(static server => server.Id);
 			
-			await foreach (var channel in state.Db.Channels.Get()) {
+			foreach (ChannelFilterKey channelFilterKey in servers.Values.Select(ChannelFilterKey.For).Order()) {
-				var channelId = channel.Id;
+				items.AddParent(channelFilterKey, channelFilterKey.Title);
-				var channelName = channel.Name;
-
-				string title;
-				if (servers.TryGetValue(channel.Server, out var server)) {
-					var titleBuilder = new StringBuilder();
-					var serverType = server.Type;
-
-					titleBuilder.Append('[')
-					            .Append(ServerTypes.ToString(serverType))
-					            .Append("] ");
-
-					if (serverType == ServerType.DirectMessage) {
-						titleBuilder.Append(channelName);
-					}
-					else {
-						titleBuilder.Append(server.Name)
-						            .Append(" - ")
-						            .Append(channelName);
 			}
 			
-					title = titleBuilder.ToString();
+			await foreach (Channel channel in state.Db.Channels.Get().OrderBy(static channel => channel.Position ?? int.MinValue).ThenBy(static channel => channel.Name)) {
-				}
+				ChannelFilterKey key = servers.TryGetValue(channel.Server, out var server)
-				else {
+					                       ? ChannelFilterKey.For(server)
-					title = channelName;
+					                       : ChannelFilterKey.Unknown;
+				
+				items.Add(key, channel.Id, channel.Name, isChecked: IncludedChannels == null || IncludedChannels.Contains(channel.Id));
 			}
 			
-				items.Add(new CheckBoxItem<ulong>(channelId) {
+			return items.ToCheckBoxItems();
-					Title = title,
-					IsChecked = IncludedChannels == null || IncludedChannels.Contains(channelId)
-				});
-			}
-
-			return items;
 		}
 		
 		const string Title = "Included Channels";
 		
-		List<CheckBoxItem<ulong>> items;
+		ImmutableArray<ICheckBoxItem> items;
 		try {
 			items = await ProgressDialog.ShowIndeterminate(window, Title, "Loading channels...", PrepareChannelItems);
 		} catch (Exception e) {
@@ -238,29 +249,34 @@ sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
 			return;
 		}
 		
-		var result = await OpenIdFilterDialog(Title, items);
+		HashSet<ulong>? result = await OpenIdFilterDialog(Title, items);
 		if (result != null) {
 			IncludedChannels = result;
 		}
 	}
 	
 	public async Task OpenUserFilterDialog() {
-		async Task<List<CheckBoxItem<ulong>>> PrepareUserItems(ProgressDialog dialog) {
+		async Task<ImmutableArray<ICheckBoxItem>> PrepareUserItems(ProgressDialog dialog) {
-			var checkBoxItems = new List<CheckBoxItem<ulong>>();
+			CheckBoxItemList<ulong, ulong> items = new CheckBoxItemList<ulong, ulong>();
 			
-			await foreach (var user in state.Db.Users.Get()) {
+			static string GetDisplayName(User user) {
-				checkBoxItems.Add(new CheckBoxItem<ulong>(user.Id) {
+				return user.DisplayName == null ? user.Name : $"{user.DisplayName} ({user.Name})";
-					Title = user.DisplayName == null ? user.Name : $"{user.DisplayName} ({user.Name})",
-					IsChecked = IncludedUsers == null || IncludedUsers.Contains(user.Id)
-				});
 			}
 			
-			return checkBoxItems;
+			await foreach ((ulong id, string name) in state.Db.Users.Get().Select(static user => (user.Id, GetDisplayName(user))).OrderBy(static pair => pair.Item2)) {
+				items.Add(
+					value: id,
+					title: name,
+					isChecked: IncludedUsers == null || IncludedUsers.Contains(id)
+				);
+			}
+			
+			return items.ToCheckBoxItems();
 		}
 		
 		const string Title = "Included Users";
 		
-		List<CheckBoxItem<ulong>> items;
+		ImmutableArray<ICheckBoxItem> items;
 		try {
 			items = await ProgressDialog.ShowIndeterminate(window, Title, "Loading users...", PrepareUserItems);
 		} catch (Exception e) {
@@ -268,23 +284,21 @@ sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
 			return;
 		}
 		
-		var result = await OpenIdFilterDialog(Title, items);
+		HashSet<ulong>? result = await OpenIdFilterDialog(Title, items);
 		if (result != null) {
 			IncludedUsers = result;
 		}
 	}
 	
-	private async Task<HashSet<ulong>?> OpenIdFilterDialog(string title, List<CheckBoxItem<ulong>> items) {
+	private async Task<HashSet<ulong>?> OpenIdFilterDialog(string title, ImmutableArray<ICheckBoxItem> items) {
-		items.Sort(static (item1, item2) => item1.Title.CompareTo(item2.Title));
-
 		var model = new CheckBoxDialogModel<ulong>(items) {
-			Title = title
+			Title = title,
 		};
 		
 		var dialog = new CheckBoxDialog { DataContext = model };
 		var result = await dialog.ShowDialog<DialogResult.OkCancel>(window);
 		
-		return result == DialogResult.OkCancel.Ok ? model.SelectedItems.Select(static item => item.Item).ToHashSet() : null;
+		return result == DialogResult.OkCancel.Ok ? model.SelectedValues.ToHashSet() : null;
 	}
 	
 	public MessageFilter CreateFilter() {

app/Desktop/Main/Controls/ServerConfigurationPanel.axaml

@@ -16,18 +16,21 @@
             <Setter Property="FontFamily" Value="Consolas,Courier" />
             <Setter Property="FontSize" Value="15" />
         </Style>
+        <Style Selector="Label">
+            <Setter Property="Margin" Value="0 5" />
+            <Setter Property="Padding" Value="0" />
+        </Style>
         <Style Selector="WrapPanel > StackPanel">
             <Setter Property="Orientation" Value="Vertical" />
-            <Setter Property="Margin" Value="0 0 10 10" />
         </Style>
     </UserControl.Styles>
 
-    <StackPanel>
+    <StackPanel Spacing="10">
         <Button Command="{Binding OnClickToggleServerButton}" Content="{Binding ToggleServerButtonText}" IsEnabled="{Binding IsToggleServerButtonEnabled}" />
-        <TextBlock TextWrapping="Wrap" Margin="0 15">
+        <TextBlock TextWrapping="Wrap" Margin="0 5">
-            The following settings determine how the tracking script communicates with this application. If you change them, you will have to copy/paste the tracking script again.
+            The following settings determine how the tracking script communicates with this application. If you change them, you will have to copy/paste the tracking script or connection code again.
         </TextBlock>
-        <WrapPanel>
+        <WrapPanel ItemSpacing="10" LineSpacing="10">
             <StackPanel>
                 <Label Target="Port">Port</Label>
                 <TextBox x:Name="Port" Width="70" Text="{Binding InputPort}" />

app/Desktop/Main/Controls/ServerConfigurationPanelModel.cs

@@ -1,30 +1,30 @@
 using System;
+using System.ComponentModel;
 using System.Threading.Tasks;
 using Avalonia.Controls;
 using Avalonia.Threading;
-using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Server;
 using DHT.Server;
 using DHT.Server.Service;
 using DHT.Utils.Logging;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Controls;
 
-sealed partial class ServerConfigurationPanelModel : ObservableObject, IDisposable {
+sealed partial class ServerConfigurationPanelModel : IDisposable {
 	private static readonly Log Log = Log.ForType<ServerConfigurationPanelModel>();
 	
-	[ObservableProperty]
+	[Notify]
-	[NotifyPropertyChangedFor(nameof(HasMadeChanges))]
 	private string inputPort;
 	
-	[ObservableProperty]
+	[Notify]
-	[NotifyPropertyChangedFor(nameof(HasMadeChanges))]
 	private string inputToken;
 	
+	[DependsOn(nameof(InputPort), nameof(InputToken))]
 	public bool HasMadeChanges => ServerConfiguration.Port.ToString() != InputPort || ServerConfiguration.Token != InputToken;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private bool isToggleServerButtonEnabled = true;
 	
 	public string ToggleServerButtonText => server.IsRunning ? "Stop Server" : "Start Server";
@@ -53,7 +53,7 @@ sealed partial class ServerConfigurationPanelModel : ObservableObject, IDisposab
 	}
 	
 	private void UpdateServerStatus() {
-		OnPropertyChanged(nameof(ToggleServerButtonText));
+		OnPropertyChanged(new PropertyChangedEventArgs(nameof(ToggleServerButtonText)));
 	}
 	
 	private async Task StartServer() {
@@ -62,7 +62,7 @@ sealed partial class ServerConfigurationPanelModel : ObservableObject, IDisposab
 		try {
 			await server.Start(ServerConfiguration.Port, ServerConfiguration.Token);
 		} catch (Exception e) {
-			Log.Error(e);
+			Log.Error("Could not start internal server.", e);
 			await Dialog.ShowOk(window, "Internal Server Error", e.Message);
 		}
 		
@@ -76,7 +76,7 @@ sealed partial class ServerConfigurationPanelModel : ObservableObject, IDisposab
 		try {
 			await server.Stop();
 		} catch (Exception e) {
-			Log.Error(e);
+			Log.Error("Could not stop internal server.", e);
 			await Dialog.ShowOk(window, "Internal Server Error", e.Message);
 		}
 		
@@ -106,7 +106,7 @@ sealed partial class ServerConfigurationPanelModel : ObservableObject, IDisposab
 		ServerConfiguration.Port = port;
 		ServerConfiguration.Token = inputToken;
 		
-		OnPropertyChanged(nameof(HasMadeChanges));
+		OnPropertyChanged(new PropertyChangedEventArgs(nameof(HasMadeChanges)));
 		
 		await StartServer();
 	}

app/Desktop/Main/Controls/StatusBarModel.cs

@@ -1,33 +1,32 @@
 using System;
-using System.Reactive.Linq;
-using Avalonia.ReactiveUI;
 using Avalonia.Threading;
-using CommunityToolkit.Mvvm.ComponentModel;
+using DHT.Desktop.Common;
 using DHT.Server;
 using DHT.Server.Service;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Controls;
 
-sealed partial class StatusBarModel : ObservableObject, IDisposable {
+sealed partial class StatusBarModel : IDisposable {
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private long? serverCount;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private long? channelCount;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private long? messageCount;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
-	[NotifyPropertyChangedFor(nameof(ServerStatusText))]
 	private ServerManager.Status serverStatus;
 	
-	public string ServerStatusText => serverStatus switch {
+	[DependsOn(nameof(ServerStatus))]
+	public string ServerStatusText => ServerStatus switch {
 		ServerManager.Status.Starting => "STARTING",
 		ServerManager.Status.Started  => "READY",
 		ServerManager.Status.Stopping => "STOPPING",
 		ServerManager.Status.Stopped  => "STOPPED",
-		_                             => ""
+		_                             => "",
 	};
 	
 	private readonly State state;
@@ -41,11 +40,11 @@ sealed partial class StatusBarModel : ObservableObject, IDisposable {
 	public StatusBarModel(State state) {
 		this.state = state;
 		
-		serverCountSubscription = state.Db.Servers.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(newServerCount => ServerCount = newServerCount);
+		serverCountSubscription = state.Db.Servers.TotalCount.SubscribeLastOnUI(newServerCount => ServerCount = newServerCount, TimeSpan.FromMilliseconds(15));
-		channelCountSubscription = state.Db.Channels.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(newChannelCount => ChannelCount = newChannelCount);
+		channelCountSubscription = state.Db.Channels.TotalCount.SubscribeLastOnUI(newChannelCount => ChannelCount = newChannelCount, TimeSpan.FromMilliseconds(15));
-		messageCountSubscription = state.Db.Messages.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(newMessageCount => MessageCount = newMessageCount);
+		messageCountSubscription = state.Db.Messages.TotalCount.SubscribeLastOnUI(newMessageCount => MessageCount = newMessageCount, TimeSpan.FromMilliseconds(15));
 		
-		state.Server.StatusChanged += OnServerStatusChanged;
+		state.Server.StatusChanged += OnStateServerStatusChanged;
 		serverStatus = state.Server.IsRunning ? ServerManager.Status.Started : ServerManager.Status.Stopped;
 	}
 	
@@ -54,10 +53,10 @@ sealed partial class StatusBarModel : ObservableObject, IDisposable {
 		channelCountSubscription.Dispose();
 		messageCountSubscription.Dispose();
 		
-		state.Server.StatusChanged -= OnServerStatusChanged;
+		state.Server.StatusChanged -= OnStateServerStatusChanged;
 	}
 	
-	private void OnServerStatusChanged(object? sender, ServerManager.Status e) {
+	private void OnStateServerStatusChanged(object? sender, ServerManager.Status e) {
 		Dispatcher.UIThread.InvokeAsync(() => ServerStatus = e);
 	}
 }

app/Desktop/Main/Dialogs/NewDatabaseSettingsDialog.axaml

@@ -0,0 +1,57 @@
+<Window xmlns="https://github.com/avaloniaui"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:namespace="clr-namespace:DHT.Desktop.Main.Dialogs"
+        mc:Ignorable="d" d:DesignWidth="450"
+        x:Class="DHT.Desktop.Main.Dialogs.NewDatabaseSettingsDialog"
+        x:DataType="namespace:NewDatabaseSettingsDialogModel"
+        Title="New Database Settings"
+        Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
+        Closing="OnClosing"
+        Width="450" SizeToContent="Height" CanResize="False"
+        WindowStartupLocation="CenterOwner">
+
+    <Window.DataContext>
+        <namespace:NewDatabaseSettingsDialogModel />
+    </Window.DataContext>
+
+    <Window.Styles>
+        <Style Selector="Label > StackPanel">
+            <Setter Property="Margin" Value="0 4 0 0" />
+            <Setter Property="Orientation" Value="Vertical" />
+            <Setter Property="Spacing" Value="5" />
+        </Style>
+        <Style Selector="TextBlock.dim">
+            <Setter Property="Foreground" Value="DimGray" />
+            <Setter Property="FontSize" Value="13" />
+        </Style>
+    </Window.Styles>
+
+    <StackPanel Orientation="Vertical" Margin="20">
+        <StackPanel Orientation="Vertical" Spacing="15">
+            <CheckBox IsChecked="{Binding SeparateFileForDownloads}">
+                <Label>
+                    <StackPanel>
+                        <TextBlock>Use a Separate Database File for Downloads</TextBlock>
+                        <TextBlock Classes="dim">Downloaded files will be stored separately from messages. This cannot be changed later.</TextBlock>
+                    </StackPanel>
+                </Label>
+            </CheckBox>
+            <CheckBox IsChecked="{Binding DownloadsAutoStart}">
+                <Label>
+                    <StackPanel>
+                        <TextBlock>Download Files Automatically</TextBlock>
+                        <TextBlock Classes="dim">Enables automatic downloads of files hosted on Discord. This can be changed later in the Downloads tab.</TextBlock>
+                    </StackPanel>
+                </Label>
+            </CheckBox>
+        </StackPanel>
+        <Panel Classes="buttons">
+            <WrapPanel HorizontalAlignment="Right">
+                <Button Click="ClickOk">OK</Button>
+            </WrapPanel>
+        </Panel>
+    </StackPanel>
+
+</Window>

app/Desktop/Main/Dialogs/NewDatabaseSettingsDialog.axaml.cs

@@ -0,0 +1,22 @@
+using System.Diagnostics.CodeAnalysis;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+
+namespace DHT.Desktop.Main.Dialogs;
+
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class NewDatabaseSettingsDialog : Window {
+	public NewDatabaseSettingsDialog() {
+		InitializeComponent();
+	}
+	
+	private void OnClosing(object? sender, WindowClosingEventArgs e) {
+		if (!e.IsProgrammatic) {
+			e.Cancel = true;
+		}
+	}
+	
+	private void ClickOk(object? sender, RoutedEventArgs e) {
+		Close();
+	}
+}

app/Desktop/Main/Dialogs/NewDatabaseSettingsDialogModel.cs

@@ -0,0 +1,11 @@
+using PropertyChanged.SourceGenerator;
+
+namespace DHT.Desktop.Main.Dialogs;
+
+sealed partial class NewDatabaseSettingsDialogModel {
+	[Notify]
+	private bool separateFileForDownloads = true;
+	
+	[Notify]
+	private bool downloadsAutoStart = true;
+}

app/Desktop/Main/MainWindowModel.cs

@@ -3,25 +3,26 @@ using System.IO;
 using System.Runtime.InteropServices;
 using System.Threading.Tasks;
 using Avalonia.Controls;
-using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Dialogs.Message;
+using DHT.Desktop.Dialogs.Progress;
 using DHT.Desktop.Main.Screens;
 using DHT.Desktop.Server;
 using DHT.Server;
 using DHT.Server.Database;
 using DHT.Utils.Logging;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main;
 
-sealed partial class MainWindowModel : ObservableObject, IAsyncDisposable {
+sealed partial class MainWindowModel : IAsyncDisposable {
 	private const string DefaultTitle = "Discord History Tracker";
 	
 	private static readonly Log Log = Log.ForType<MainWindowModel>();
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private string title = DefaultTitle;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private UserControl currentScreen;
 	
 	private readonly WelcomeScreen welcomeScreen;
@@ -46,7 +47,7 @@ sealed partial class MainWindowModel : ObservableObject, IAsyncDisposable {
 		welcomeScreen = new WelcomeScreen { DataContext = welcomeScreenModel };
 		currentScreen = welcomeScreen;
 		
-		var dbFile = args.DatabaseFile;
+		string? dbFile = args.DatabaseFile;
 		if (!string.IsNullOrWhiteSpace(dbFile)) {
 			async void OnWindowOpened(object? o, EventArgs eventArgs) {
 				window.Opened -= OnWindowOpened;
@@ -88,14 +89,21 @@ sealed partial class MainWindowModel : ObservableObject, IAsyncDisposable {
 		try {
 			await state.Server.Start(ServerConfiguration.Port, ServerConfiguration.Token);
 		} catch (Exception ex) {
-			Log.Error(ex);
+			Log.Error("Could not start internal server.", ex);
 			await Dialog.ShowOk(window, "Internal Server Error", ex.Message);
 		}
 		
+		try {
 			mainContentScreenModel = new MainContentScreenModel(window, state);
 			mainContentScreenModel.DatabaseClosed += MainContentScreenModelOnDatabaseClosed;
-		
 			await mainContentScreenModel.Initialize();
+		} catch (Exception ex) {
+			Log.Error("Could not initialize content screen.", ex);
+			await Dialog.ShowOk(window, "Initialization Error", ex.Message);
+			await DisposeContent();
+			await DisposeState();
+			return;
+		}
 		
 		Title = Path.GetFileName(state.Db.Path) + " - " + DefaultTitle;
 		CurrentScreen = new MainContentScreen { DataContext = mainContentScreenModel };
@@ -104,32 +112,33 @@ sealed partial class MainWindowModel : ObservableObject, IAsyncDisposable {
 	}
 	
 	private async void MainContentScreenModelOnDatabaseClosed(object? sender, EventArgs e) {
+		await DisposeContent();
+		
+		Title = DefaultTitle;
+		CurrentScreen = welcomeScreen;
+		
+		await DisposeState();
+		
+		welcomeScreenModel.DatabaseSelected += OnDatabaseSelected;
+	}
+	
+	private async Task DisposeContent() {
 		if (mainContentScreenModel != null) {
 			mainContentScreenModel.DatabaseClosed -= MainContentScreenModelOnDatabaseClosed;
 			await mainContentScreenModel.DisposeAsync();
 			mainContentScreenModel = null;
 		}
-
-		await DisposeState();
-
-		Title = DefaultTitle;
-		CurrentScreen = welcomeScreen;
-
-		welcomeScreenModel.DatabaseSelected += OnDatabaseSelected;
 	}
 	
 	private async Task DisposeState() {
 		if (state != null) {
-			await state.DisposeAsync();
+			await DelayedProgressDialog.Await(() => state.DisposeAsync().AsTask(), TimeSpan.FromMilliseconds(200), window, "Close Database", "Please wait for the database to close...");
 			state = null;
 		}
 	}
 	
 	public async ValueTask DisposeAsync() {
-		if (mainContentScreenModel != null) {
+		await DisposeContent();
-			await mainContentScreenModel.DisposeAsync();
-		}
-		
 		await DisposeState();
 	}
 }

app/Desktop/Main/Pages/AdvancedPage.axaml

@@ -16,11 +16,5 @@
         <Expander Header="Internal Server Configuration" IsExpanded="True">
             <controls:ServerConfigurationPanel DataContext="{Binding ServerConfigurationModel}" />
         </Expander>
-        <Expander Header="Database Tools" IsExpanded="True">
-            <StackPanel Orientation="Vertical" Spacing="10">
-                <TextBlock TextWrapping="Wrap">Recreates the database to remove any traces of deleted data, which frees up space and prevents forensic recovery.</TextBlock>
-                <Button Command="{Binding VacuumDatabase}">Vacuum Database</Button>
-            </StackPanel>
-        </Expander>
     </StackPanel>
 </UserControl>

app/Desktop/Main/Pages/AdvancedPageModel.cs

@@ -1,8 +1,5 @@
 using System;
-using System.Threading.Tasks;
 using Avalonia.Controls;
-using DHT.Desktop.Dialogs.Message;
-using DHT.Desktop.Dialogs.Progress;
 using DHT.Desktop.Main.Controls;
 using DHT.Server;
 
@@ -11,26 +8,14 @@ namespace DHT.Desktop.Main.Pages;
 sealed class AdvancedPageModel : IDisposable {
 	public ServerConfigurationPanelModel ServerConfigurationModel { get; }
 	
-	private readonly Window window;
-	private readonly State state;
-
 	[Obsolete("Designer")]
 	public AdvancedPageModel() : this(null!, State.Dummy) {}
 	
 	public AdvancedPageModel(Window window, State state) {
-		this.window = window;
-		this.state = state;
-
 		ServerConfigurationModel = new ServerConfigurationPanelModel(window, state);
 	}
 	
 	public void Dispose() {
 		ServerConfigurationModel.Dispose();
 	}
-
-	public async Task VacuumDatabase() {
-		const string Title = "Vacuum Database";
-		await ProgressDialog.ShowIndeterminate(window, Title, "Vacuuming database...", _ => state.Db.Vacuum());
-		await Dialog.ShowOk(window, Title, "Done.");
-	}
 }

app/Desktop/Main/Pages/DatabasePage.axaml

@@ -11,22 +11,22 @@
         <pages:DatabasePageModel />
     </Design.DataContext>
 
-    <UserControl.Styles>
-        <Style Selector="WrapPanel > Button">
-            <Setter Property="Margin" Value="0 0 10 10" />
-        </Style>
-    </UserControl.Styles>
-
     <StackPanel Spacing="10">
         <DockPanel>
             <Button Command="{Binding CloseDatabase}" DockPanel.Dock="Right">Close Database</Button>
             <TextBox Text="{Binding Db.Path}" Width="NaN" Margin="0 0 10 0" IsReadOnly="True" />
         </DockPanel>
-        <WrapPanel>
+        <WrapPanel ItemSpacing="10" LineSpacing="10">
             <Button Command="{Binding OpenDatabaseFolder}">Open Database Folder</Button>
             <Button Command="{Binding MergeWithDatabase}">Merge with Database(s)...</Button>
             <Button Command="{Binding ImportLegacyArchive}">Import Legacy Archive(s)...</Button>
         </WrapPanel>
+        <Expander Header="Advanced Tools" Margin="0 25 0 0">
+            <StackPanel Orientation="Vertical" Spacing="10">
+                <TextBlock TextWrapping="Wrap">Recreate the database to free up space after deleting data.</TextBlock>
+                <Button Command="{Binding VacuumDatabase}">Vacuum Database</Button>
+            </StackPanel>
+        </Expander>
     </StackPanel>
 
 </UserControl>

app/Desktop/Main/Pages/DatabasePageModel.cs

@@ -19,6 +19,7 @@ using DHT.Server.Data;
 using DHT.Server.Database;
 using DHT.Server.Database.Import;
 using DHT.Server.Database.Sqlite.Schema;
+using DHT.Server.Database.Sqlite.Utils;
 using DHT.Utils.Logging;
 
 namespace DHT.Desktop.Main.Pages;
@@ -54,11 +55,11 @@ sealed class DatabasePageModel {
 				break;
 			
 			case PlatformID.Unix:
-				Process.Start("xdg-open", new string[] { folder });
+				Process.Start("xdg-open", [folder]);
 				break;
 			
 			case PlatformID.MacOSX:
-				Process.Start("open", new string[] { folder });
+				Process.Start("open", [folder]);
 				break;
 			
 			default:
@@ -72,16 +73,32 @@ sealed class DatabasePageModel {
 	}
 	
 	public async Task MergeWithDatabase() {
-		var paths = await DatabaseGui.NewOpenDatabaseFilesDialog(window, Path.GetDirectoryName(Db.Path));
+		string[] paths = await DatabaseGui.NewOpenDatabaseFilesDialog(window, Path.GetDirectoryName(Db.Path));
-		if (paths.Length > 0) {
+		if (paths.Length == 0) {
-			await ProgressDialog.Show(window, "Database Merge", async (dialog, callback) => await MergeWithDatabaseFromPaths(Db, paths, dialog, callback));
+			return;
-		}
 		}
 		
-	private static async Task MergeWithDatabaseFromPaths(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback) {
+		const string Title = "Database Merge";
-		var schemaUpgradeCallbacks = new SchemaUpgradeCallbacks(dialog, paths.Length);
 		
-		await PerformImport(target, paths, dialog, callback, "Database Merge", "Database Error", "database file", async path => {
+		var result = new TaskCompletionSource<ImportResult?>();
+		try {
+			var dialog = new ProgressDialog();
+			dialog.DataContext = new ProgressDialogModel(Title, async callbacks => result.SetResult(await MergeWithDatabaseFromPaths(Db, paths, dialog, callbacks)), progressItems: 2);
+			await dialog.ShowProgressDialog(window);
+		} catch (Exception e) {
+			Log.Error("Could not merge databases.", e);
+			await Dialog.ShowOk(window, Title, "Could not merge databases: " + e.Message);
+			return;
+		}
+		
+		await Dialog.ShowOk(window, Title, GetImportDialogMessage(result.Task.Result, "database file"));
+	}
+	
+	private static async Task<ImportResult?> MergeWithDatabaseFromPaths(IDatabaseFile target, string[] paths, ProgressDialog dialog, IReadOnlyList<IProgressCallback> callbacks) {
+		var schemaUpgradeCallbacks = new SchemaUpgradeCallbacks(dialog, callbacks[1], paths.Length);
+		var databaseMergeProgressCallback = new DatabaseMergeProgressCallback(callbacks[1]);
+		
+		return await PerformImport(target, paths, dialog, callbacks[0], "Database Merge", async path => {
 			IDatabaseFile? db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, dialog, schemaUpgradeCallbacks);
 			
 			if (db == null) {
@@ -89,7 +106,7 @@ sealed class DatabasePageModel {
 			}
 			
 			try {
-				await target.AddFrom(db);
+				await target.Merge(db, databaseMergeProgressCallback);
 				return true;
 			} finally {
 				await db.DisposeAsync();
@@ -97,14 +114,11 @@ sealed class DatabasePageModel {
 		});
 	}
 	
-	private sealed class SchemaUpgradeCallbacks : ISchemaUpgradeCallbacks {
+	private sealed class SchemaUpgradeCallbacks(ProgressDialog dialog, IProgressCallback callback, int total) : ISchemaUpgradeCallbacks {
-		private readonly ProgressDialog dialog;
-		private readonly int total;
 		private bool? decision;
 		
-		public SchemaUpgradeCallbacks(ProgressDialog dialog, int total) {
+		public Task<InitialDatabaseSettings?> GetInitialDatabaseSettings() {
-			this.total = total;
+			return Task.FromResult<InitialDatabaseSettings?>(null);
-			this.dialog = dialog;
 		}
 		
 		public async Task<bool> CanUpgrade() {
@@ -114,6 +128,7 @@ sealed class DatabasePageModel {
 		}
 		
 		public Task Start(int versionSteps, Func<ISchemaUpgradeCallbacks.IProgressReporter, Task> doUpgrade) {
+			callback.UpdateIndeterminate("Upgrading database...");
 			return doUpgrade(new NullReporter());
 		}
 		
@@ -132,22 +147,49 @@ sealed class DatabasePageModel {
 		}
 	}
 	
+	private sealed class DatabaseMergeProgressCallback(IProgressCallback callback) : DatabaseMerging.IProgressCallback {
+		public void OnImportingMetadata() {
+			callback.UpdateIndeterminate("Importing metadata...");
+		}
+		
+		public void OnMessagesImported(long finished, long total) {
+			callback.Update("Importing messages...", finished, total);
+		}
+		
+		public void OnDownloadsImported(long finished, long total) {
+			callback.Update("Importing downloaded files...", finished, total);
+		}
+	}
+	
 	public async Task ImportLegacyArchive() {
-		var paths = await window.StorageProvider.OpenFiles(new FilePickerOpenOptions {
+		string[] paths = await window.StorageProvider.OpenFiles(new FilePickerOpenOptions {
 			Title = "Open Legacy DHT Archive",
 			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, Path.GetDirectoryName(Db.Path)),
-			AllowMultiple = true
+			AllowMultiple = true,
 		});
 		
-		if (paths.Length > 0) {
+		if (paths.Length == 0) {
-			await ProgressDialog.Show(window, "Legacy Archive Import", async (dialog, callback) => await ImportLegacyArchiveFromPaths(Db, paths, dialog, callback));
+			return;
-		}
 		}
 		
-	private static async Task ImportLegacyArchiveFromPaths(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback) {
+		const string Title = "Legacy Archive Import";
+		
+		ImportResult? result;
+		try {
+			result = await ProgressDialog.Show(window, Title, async (dialog, callback) => await ImportLegacyArchiveFromPaths(Db, paths, dialog, callback));
+		} catch (Exception e) {
+			Log.Error("Could not import legacy archives.", e);
+			await Dialog.ShowOk(window, Title, "Could not import legacy archives: " + e.Message);
+			return;
+		}
+		
+		await Dialog.ShowOk(window, Title, GetImportDialogMessage(result, "archive file"));
+	}
+	
+	private static async Task<ImportResult?> ImportLegacyArchiveFromPaths(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback) {
 		var fakeSnowflake = new FakeSnowflake();
 		
-		await PerformImport(target, paths, dialog, callback, "Legacy Archive Import", "Legacy Archive Error", "archive file", async path => {
+		return await PerformImport(target, paths, dialog, callback, "Legacy Archive Import", async path => {
 			await using var jsonStream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
 			
 			return await LegacyArchiveImport.Read(jsonStream, target, fakeSnowflake, async servers => {
@@ -167,16 +209,16 @@ sealed class DatabasePageModel {
 		
 		var items = new List<TextBoxItem<DHT.Server.Data.Server>>();
 		
-		foreach (var server in servers.OrderBy(static server => server.Type).ThenBy(static server => server.Name)) {
+		foreach (DHT.Server.Data.Server server in servers.OrderBy(static server => server.Type).ThenBy(static server => server.Name)) {
 			items.Add(new TextBoxItem<DHT.Server.Data.Server>(server) {
 				Title = server.Name + " (" + ServerTypes.ToNiceString(server.Type) + ")",
-				ValidityCheck = IsValidSnowflake
+				ValidityCheck = IsValidSnowflake,
 			});
 		}
 		
 		var model = new TextBoxDialogModel<DHT.Server.Data.Server>(items) {
 			Title = "Imported Server IDs",
-			Description = "Please fill in the IDs of servers and direct messages. First enable Developer Mode in Discord, then right-click each server or direct message, click 'Copy ID', and paste it into the input field. If a server no longer exists, leave its input field empty to use a random ID."
+			Description = "Please fill in the IDs of servers and direct messages. First enable Developer Mode in Discord, then right-click each server or direct message, click 'Copy ID', and paste it into the input field. If a server no longer exists, leave its input field empty to use a random ID.",
 		};
 		
 		var dialog = new TextBoxDialog { DataContext = model };
@@ -191,19 +233,19 @@ sealed class DatabasePageModel {
 		            .ToDictionary(static item => item.Item, static item => ulong.Parse(item.Value));
 	}
 	
-	private static async Task PerformImport(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback, string neutralDialogTitle, string errorDialogTitle, string itemName, Func<string, Task<bool>> performImport) {
+	private static async Task<ImportResult?> PerformImport(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback, string dialogTitle, Func<string, Task<bool>> performImport) {
 		int total = paths.Length;
-		var oldStatistics = await DatabaseStatistics.Take(target);
+		DatabaseStatistics oldStatistics = await DatabaseStatistics.Take(target);
 		
 		int successful = 0;
 		int finished = 0;
 		
 		foreach (string path in paths) {
-			await callback.Update(Path.GetFileName(path), finished, total);
+			await callback.Update("File: " + Path.GetFileName(path), finished, total);
 			++finished;
 			
 			if (!File.Exists(path)) {
-				await Dialog.ShowOk(dialog, errorDialogTitle, "File '" + Path.GetFileName(path) + "' no longer exists.");
+				await Dialog.ShowOk(dialog, dialogTitle, "File '" + Path.GetFileName(path) + "' no longer exists.");
 				continue;
 			}
 			
@@ -212,20 +254,19 @@ sealed class DatabasePageModel {
 					++successful;
 				}
 			} catch (Exception ex) {
-				Log.Error(ex);
+				Log.Error("Could not import file: " + path, ex);
-				await Dialog.ShowOk(dialog, errorDialogTitle, "File '" + Path.GetFileName(path) + "' could not be imported: " + ex.Message);
+				await Dialog.ShowOk(dialog, dialogTitle, "File '" + Path.GetFileName(path) + "' could not be imported: " + ex.Message);
 			}
 		}
 		
 		await callback.Update("Done", finished, total);
 		
 		if (successful == 0) {
-			await Dialog.ShowOk(dialog, neutralDialogTitle, "Nothing was imported.");
+			return null;
-			return;
 		}
 		
-		var newStatistics = await DatabaseStatistics.Take(target);
+		DatabaseStatistics newStatistics = await DatabaseStatistics.Take(target);
-		await Dialog.ShowOk(dialog, neutralDialogTitle, GetImportDialogMessage(oldStatistics, newStatistics, successful, total, itemName));
+		return new ImportResult(oldStatistics, newStatistics, successful, total);
 	}
 	
 	private sealed record DatabaseStatistics(long ServerCount, long ChannelCount, long UserCount, long MessageCount) {
@@ -239,20 +280,29 @@ sealed class DatabasePageModel {
 		}
 	}
 	
-	private static string GetImportDialogMessage(DatabaseStatistics oldStatistics, DatabaseStatistics newStatistics, int successfulItems, int totalItems, string itemName) {
+	private sealed record ImportResult(DatabaseStatistics OldStatistics, DatabaseStatistics NewStatistics, int SuccessfulItems, int TotalItems);
+	
+	private static string GetImportDialogMessage(ImportResult? result, string itemName) {
+		if (result == null) {
+			return "Nothing was imported.";
+		}
+		
+		var oldStatistics = result.OldStatistics;
+		var newStatistics = result.NewStatistics;
+		
 		long newServers = newStatistics.ServerCount - oldStatistics.ServerCount;
 		long newChannels = newStatistics.ChannelCount - oldStatistics.ChannelCount;
 		long newUsers = newStatistics.UserCount - oldStatistics.UserCount;
 		long newMessages = newStatistics.MessageCount - oldStatistics.MessageCount;
 		
-		StringBuilder message = new StringBuilder();
+		var message = new StringBuilder();
 		message.Append("Processed ");
 		
-		if (successfulItems == totalItems) {
+		if (result.SuccessfulItems == result.TotalItems) {
-			message.Append(successfulItems.Pluralize(itemName));
+			message.Append(result.SuccessfulItems.Pluralize(itemName));
 		}
 		else {
-			message.Append(successfulItems.Format()).Append(" out of ").Append(totalItems.Pluralize(itemName));
+			message.Append(result.SuccessfulItems.Format()).Append(" out of ").Append(result.TotalItems.Pluralize(itemName));
 		}
 		
 		message.Append(" and added:\n\n  \u2022 ");
@@ -263,4 +313,18 @@ sealed class DatabasePageModel {
 		
 		return message.ToString();
 	}
+	
+	public async Task VacuumDatabase() {
+		const string Title = "Vacuum Database";
+		
+		try {
+			await ProgressDialog.ShowIndeterminate(window, Title, "Vacuuming database...", _ => Db.Vacuum());
+		} catch (Exception e) {
+			Log.Error("Could not vacuum database.", e);
+			await Dialog.ShowOk(window, Title, "Could not vacuum database: " + e.Message);
+			return;
+		}
+		
+		await Dialog.ShowOk(window, Title, "Done.");
+	}
 }

app/Desktop/Main/Pages/DebugPage.axaml

@@ -16,24 +16,27 @@
             <Setter Property="FontFamily" Value="Consolas,Courier" />
             <Setter Property="FontSize" Value="15" />
         </Style>
+        <Style Selector="Label">
+            <Setter Property="Margin" Value="0" />
+            <Setter Property="Padding" Value="0" />
+        </Style>
         <Style Selector="WrapPanel > StackPanel">
             <Setter Property="Orientation" Value="Vertical" />
-            <Setter Property="Margin" Value="0 0 10 10" />
         </Style>
     </UserControl.Styles>
 
     <StackPanel Orientation="Vertical" Spacing="10">
         <Expander Header="Generate Random Data" IsExpanded="True">
-            <WrapPanel>
+            <WrapPanel ItemSpacing="10" LineSpacing="10">
-                <StackPanel>
+                <StackPanel Spacing="8">
                     <Label Target="Channels">Channels</Label>
                     <TextBox x:Name="Channels" Width="100" Text="{Binding GenerateChannels}" />
                 </StackPanel>
-                <StackPanel>
+                <StackPanel Spacing="8">
                     <Label Target="Users">Users</Label>
                     <TextBox x:Name="Users" Width="100" Text="{Binding GenerateUsers}" />
                 </StackPanel>
-                <StackPanel>
+                <StackPanel Spacing="8">
                     <Label Target="Messages">Messages</Label>
                     <TextBox x:Name="Messages" Width="100" Text="{Binding GenerateMessages}" />
                 </StackPanel>
@@ -42,5 +45,8 @@
                 </StackPanel>
             </WrapPanel>
         </Expander>
+        <Expander Header="About" IsExpanded="True">
+            <TextBlock Text="{Binding SqliteVersion, StringFormat=Sqlite Version: {0}}" />
+        </Expander>
     </StackPanel>
 </UserControl>

app/Desktop/Main/Pages/DebugPageModel.cs

@@ -9,14 +9,18 @@ using DHT.Desktop.Dialogs.Progress;
 using DHT.Server;
 using DHT.Server.Data;
 using DHT.Server.Service;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Pages;
 
-sealed class DebugPageModel {
+sealed partial class DebugPageModel {
 	public string GenerateChannels { get; set; } = "0";
 	public string GenerateUsers { get; set; } = "0";
 	public string GenerateMessages { get; set; } = "0";
 	
+	[Notify(Setter.Private)]
+	private string? sqliteVersion = string.Empty;
+	
 	private readonly Window window;
 	private readonly State state;
 	
@@ -28,6 +32,10 @@ sealed class DebugPageModel {
 		this.state = state;
 	}
 	
+	public async Task Initialize() {
+		SqliteVersion = await state.Db.GetVersion() ?? "<unknown>";
+	}
+	
 	public async void OnClickAddRandomDataToDatabase() {
 		if (!int.TryParse(GenerateChannels, out int channels) || channels < 1) {
 			await Dialog.ShowOk(window, "Generate Random Data", "Amount of channels must be at least 1!");
@@ -51,7 +59,7 @@ sealed class DebugPageModel {
 	
 	private async Task GenerateRandomData(int channelCount, int userCount, int messageCount, IProgressCallback callback) {
 		int batchCount = (messageCount + BatchSize - 1) / BatchSize;
-		await callback.Update("Adding messages in batches of " + BatchSize, 0, batchCount);
+		await callback.Update("Adding messages in batches of " + BatchSize, finishedItems: 0, totalItems: batchCount);
 		
 		var rand = new Random();
 		var server = new DHT.Server.Data.Server {
@@ -60,46 +68,46 @@ sealed class DebugPageModel {
 			Type = ServerType.Server,
 		};
 		
-		var channels = Enumerable.Range(0, channelCount).Select(i => new Channel {
+		Channel[] channels = Enumerable.Range(start: 0, channelCount).Select(i => new Channel {
 			Id = RandomId(rand),
 			Server = server.Id,
 			Name = RandomName("c"),
 			ParentId = null,
 			Position = i,
-			Topic = RandomText(rand, 10),
+			Topic = RandomText(rand, maxWords: 10),
 			Nsfw = rand.Next(4) == 0,
 		}).ToArray();
 		
-		var users = Enumerable.Range(0, userCount).Select(_ => new User {
+		User[] users = Enumerable.Range(start: 0, userCount).Select(_ => new User {
 			Id = RandomId(rand),
 			Name = RandomName("u"),
 			DisplayName = RandomName("u"),
-			AvatarUrl = null,
+			AvatarHash = null,
-			Discriminator = rand.Next(0, 9999).ToString(),
+			Discriminator = rand.Next(minValue: 0, maxValue: 9999).ToString(),
 		}).ToArray();
 		
 		await state.Db.Users.Add(users);
 		await state.Db.Servers.Add([server]);
 		await state.Db.Channels.Add(channels);
 		
-		var now = DateTimeOffset.Now;
+		DateTimeOffset now = DateTimeOffset.Now;
 		int batchIndex = 0;
 		
 		while (messageCount > 0) {
 			int hourOffset = batchIndex;
 			
-			var messages = Enumerable.Range(0, Math.Min(messageCount, BatchSize)).Select(i => {
+			Message[] messages = Enumerable.Range(start: 0, Math.Min(messageCount, BatchSize)).Select(i => {
 				DateTimeOffset time = now.AddHours(hourOffset).AddMinutes(i * 60.0 / BatchSize);
-				DateTimeOffset? edit = rand.Next(100) == 0 ? time.AddSeconds(rand.Next(1, 60)) : null;
+				DateTimeOffset? edit = rand.Next(100) == 0 ? time.AddSeconds(rand.Next(minValue: 1, maxValue: 60)) : null;
 				
-				var timeMillis = time.ToUnixTimeMilliseconds();
+				long timeMillis = time.ToUnixTimeMilliseconds();
-				var editMillis = edit?.ToUnixTimeMilliseconds();
+				long? editMillis = edit?.ToUnixTimeMilliseconds();
 				
 				return new Message {
 					Id = (ulong) timeMillis,
 					Sender = RandomBiasedIndex(rand, users).Id,
 					Channel = RandomBiasedIndex(rand, channels).Id,
-					Text = RandomText(rand, 100),
+					Text = RandomText(rand, maxWords: 100),
 					Timestamp = timeMillis,
 					EditTimestamp = editMillis,
 					RepliedToId = null,
@@ -153,12 +161,12 @@ sealed class DebugPageModel {
 		"vanilla",
 		"watercress", "watermelon",
 		"yam",
-		"zucchini"
+		"zucchini",
 	];
 	
 	private static string RandomText(Random rand, int maxWords) {
-		int wordCount = 1 + (int) Math.Floor(maxWords * Math.Pow(rand.NextDouble(), 3));
+		int wordCount = 1 + (int) Math.Floor(maxWords * Math.Pow(rand.NextDouble(), y: 3));
-		return string.Join(' ', Enumerable.Range(0, wordCount).Select(_ => RandomWords[rand.Next(RandomWords.Length)]));
+		return string.Join(separator: ' ', Enumerable.Range(start: 0, wordCount).Select(_ => RandomWords[rand.Next(RandomWords.Length)]));
 	}
 }
 #else
@@ -169,6 +177,8 @@ sealed class DebugPageModel {
 	public string GenerateUsers { get; set; } = "0";
 	public string GenerateMessages { get; set; } = "0";
 
+	public string SqliteVersion => string.Empty;
+	
 	public void OnClickAddRandomDataToDatabase() {}
 }
 #endif

app/Desktop/Main/Pages/DownloadsPage.axaml

@@ -13,9 +13,6 @@
     </Design.DataContext>
 
     <UserControl.Styles>
-        <Style Selector="Expander">
-            <Setter Property="Margin" Value="0 5 0 0" />
-        </Style>
         <Style Selector="DataGridColumnHeader">
             <Setter Property="FontWeight" Value="Medium" />
         </Style>
@@ -31,15 +28,16 @@
     </UserControl.Styles>
 
     <StackPanel Orientation="Vertical" Spacing="20">
-        <StackPanel Orientation="Horizontal" Spacing="10">
+        <WrapPanel Orientation="Horizontal" ItemSpacing="10" LineSpacing="10">
             <Button Command="{Binding OnClickToggleDownload}" Content="{Binding ToggleDownloadButtonText}" IsEnabled="{Binding IsToggleDownloadButtonEnabled}" />
-            <Button Command="{Binding OnClickRetryFailedDownloads}" IsEnabled="{Binding IsRetryFailedOnDownloadsButtonEnabled}">Retry Failed Downloads</Button>
+            <Button Command="{Binding OnClickRetryFailed}" IsEnabled="{Binding IsRetryFailedOnDownloadsButtonEnabled}">Retry Failed</Button>
-        </StackPanel>
+            <Button Command="{Binding OnClickDeleteOrphaned}">Delete Orphaned</Button>
+            <Button Command="{Binding OnClickExportAll}" IsEnabled="{Binding HasSuccessfulDownloads}">Export All...</Button>
+        </WrapPanel>
         <controls:DownloadItemFilterPanel DataContext="{Binding FilterModel}" IsEnabled="{Binding !$parent[UserControl].((pages:DownloadsPageModel)DataContext).IsDownloading}" />
         <TextBlock TextWrapping="Wrap">
             Downloading state and filter settings are remembered per-database.
         </TextBlock>
-        <StackPanel Orientation="Vertical" Spacing="12">
         <Expander Header="Download Status" IsExpanded="True">
             <DataGrid ItemsSource="{Binding StatisticsRows}" AutoGenerateColumns="False" CanUserReorderColumns="False" CanUserResizeColumns="False" CanUserSortColumns="False" IsReadOnly="True">
                 <DataGrid.Columns>
@@ -50,5 +48,4 @@
             </DataGrid>
         </Expander>
     </StackPanel>
-    </StackPanel>
 </UserControl>

app/Desktop/Main/Pages/DownloadsPageModel.cs

@@ -1,40 +1,50 @@
 using System;
+using System.Collections.Generic;
 using System.Collections.ObjectModel;
-using System.Reactive.Linq;
+using System.ComponentModel;
 using System.Threading.Tasks;
-using Avalonia.ReactiveUI;
+using Avalonia.Controls;
-using CommunityToolkit.Mvvm.ComponentModel;
+using Avalonia.Platform.Storage;
 using DHT.Desktop.Common;
+using DHT.Desktop.Dialogs.File;
+using DHT.Desktop.Dialogs.Message;
+using DHT.Desktop.Dialogs.Progress;
 using DHT.Desktop.Main.Controls;
 using DHT.Server;
+using DHT.Server.Data;
 using DHT.Server.Data.Aggregations;
 using DHT.Server.Data.Filters;
 using DHT.Server.Data.Settings;
 using DHT.Server.Download;
 using DHT.Utils.Logging;
+using DHT.Utils.Observables;
 using DHT.Utils.Tasks;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Pages;
 
-sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
+sealed partial class DownloadsPageModel : IAsyncDisposable {
 	private static readonly Log Log = Log.ForType<DownloadsPageModel>();
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private bool isToggleDownloadButtonEnabled = true;
 	
+	[DependsOn(nameof(IsDownloading))]
 	public string ToggleDownloadButtonText => IsDownloading ? "Stop Downloading" : "Start Downloading";
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
-	[NotifyPropertyChangedFor(nameof(IsRetryFailedOnDownloadsButtonEnabled))]
 	private bool isRetryingFailedDownloads = false;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
-	[NotifyPropertyChangedFor(nameof(IsRetryFailedOnDownloadsButtonEnabled))]
+	private bool hasSuccessfulDownloads;
+	
+	[Notify(Setter.Private)]
 	private bool hasFailedDownloads;
 	
+	[DependsOn(nameof(IsRetryingFailedDownloads), nameof(HasFailedDownloads))]
 	public bool IsRetryFailedOnDownloadsButtonEnabled => !IsRetryingFailedDownloads && HasFailedDownloads;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private string downloadMessage = "";
 	
 	public DownloadItemFilterPanelModel FilterModel { get; }
@@ -48,6 +58,7 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 	
 	public bool IsDownloading => state.Downloader.IsDownloading;
 	
+	private readonly Window window;
 	private readonly State state;
 	private readonly ThrottledTask<DownloadStatusStatistics> downloadStatisticsTask;
 	private readonly IDisposable downloadItemCountSubscription;
@@ -55,9 +66,10 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 	private IDisposable? finishedItemsSubscription;
 	private DownloadItemFilter? currentDownloadFilter;
 	
-	public DownloadsPageModel() : this(State.Dummy) {}
+	public DownloadsPageModel() : this(null!, State.Dummy) {}
 	
-	public DownloadsPageModel(State state) {
+	public DownloadsPageModel(Window window, State state) {
+		this.window = window;
 		this.state = state;
 		
 		FilterModel = new DownloadItemFilterPanelModel(state);
@@ -66,11 +78,11 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 			statisticsPending,
 			statisticsDownloaded,
 			statisticsFailed,
-			statisticsSkipped
+			statisticsSkipped,
 		];
 		
-		downloadStatisticsTask = new ThrottledTask<DownloadStatusStatistics>(Log, UpdateStatistics, TaskScheduler.FromCurrentSynchronizationContext());
+		downloadStatisticsTask = new ThrottledTask<DownloadStatusStatistics>(Log, UpdateStatistics, TimeSpan.FromMilliseconds(100), TaskScheduler.FromCurrentSynchronizationContext());
-		downloadItemCountSubscription = state.Db.Downloads.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnDownloadCountChanged);
+		downloadItemCountSubscription = state.Db.Downloads.TotalCount.SubscribeLastOnUI(OnDownloadCountChanged, TimeSpan.FromMilliseconds(15));
 		
 		RecomputeDownloadStatistics();
 	}
@@ -78,8 +90,13 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 	public async Task Initialize() {
 		await FilterModel.Initialize();
 		
-		if (await state.Db.Settings.Get(SettingsKey.DownloadsAutoStart, false)) {
+		if (await state.Db.Settings.Get(SettingsKey.DownloadsAutoStart, defaultValue: false)) {
+			try {
 				await StartDownload();
+			} catch (Exception e) {
+				Log.Error("Could not automatically start downloads.", e);
+				await Dialog.ShowOk(window, "Database Error", "Could not automatically start downloads: " + e.Message);
+			}
 		}
 	}
 	
@@ -98,23 +115,43 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 	
 	public async Task OnClickToggleDownload() {
 		IsToggleDownloadButtonEnabled = false;
-
+		try {
 			if (IsDownloading) {
 				await StopDownload();
 			}
 			else {
+				try {
 					await StartDownload();
+				} catch (Exception e) {
+					Log.Error("Could not start downloads.", e);
+					await Dialog.ShowOk(window, "Database Error", "Could not start downloads: " + e.Message);
+					return;
+				}
 			}
 			
+			try {
 				await state.Db.Settings.Set(SettingsKey.DownloadsAutoStart, IsDownloading);
+			} catch (Exception e) {
+				Log.Error("Could not update auto-start setting in database.", e);
+			}
+		} finally {
 			IsToggleDownloadButtonEnabled = true;
 		}
+	}
 	
 	private async Task StartDownload() {
 		await state.Db.Downloads.MoveDownloadingItemsBackToQueue();
 		
-		var finishedItems = await state.Downloader.Start(currentDownloadFilter = FilterModel.CreateFilter());
+		try {
-		finishedItemsSubscription = finishedItems.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnItemFinished);
+			currentDownloadFilter = FilterModel.CreateFilter();
+			ObservableValue<DownloadItem> finishedItems = await state.Downloader.Start(currentDownloadFilter);
+			finishedItemsSubscription = finishedItems.SubscribeLastOnUI(OnItemFinished, TimeSpan.FromMilliseconds(15));
+		} catch (Exception) {
+			finishedItemsSubscription?.Dispose();
+			finishedItemsSubscription = null;
+			currentDownloadFilter = null;
+			throw;
+		}
 		
 		OnDownloadStateChanged();
 	}
@@ -125,30 +162,29 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 		
 		finishedItemsSubscription?.Dispose();
 		finishedItemsSubscription = null;
-			
 		currentDownloadFilter = null;
+		
 		OnDownloadStateChanged();
 	}
 	
 	private void OnDownloadStateChanged() {
 		RecomputeDownloadStatistics();
 		
-		OnPropertyChanged(nameof(ToggleDownloadButtonText));
+		OnPropertyChanged(new PropertyChangedEventArgs(nameof(IsDownloading)));
-		OnPropertyChanged(nameof(IsDownloading));
 	}
 	
 	private void OnItemFinished(DownloadItem item) {
 		RecomputeDownloadStatistics();
 	}
 	
-	public async Task OnClickRetryFailedDownloads() {
+	public async Task OnClickRetryFailed() {
 		IsRetryingFailedDownloads = true;
-
 		try {
 			await state.Db.Downloads.RetryFailed();
 			RecomputeDownloadStatistics();
 		} catch (Exception e) {
-			Log.Error(e);
+			Log.Error("Could not retry failed downloads.", e);
+			await Dialog.ShowOk(window, "Retry Failed", "Could not retry failed downloads: " + e.Message);
 		} finally {
 			IsRetryingFailedDownloads = false;
 		}
@@ -158,7 +194,97 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 		downloadStatisticsTask.Post(cancellationToken => state.Db.Downloads.GetStatistics(currentDownloadFilter ?? new DownloadItemFilter(), cancellationToken));
 	}
 	
-	private void UpdateStatistics(DownloadStatusStatistics statusStatistics) {
+	public async Task OnClickDeleteOrphaned() {
+		const string Title = "Delete Orphaned Downloads";
+		
+		try {
+			await ProgressDialog.Show(window, Title, async (_, callback) => {
+				await callback.UpdateIndeterminate("Searching for orphaned downloads...");
+				
+				HashSet<string> reachableNormalizedUrls = [];
+				HashSet<string> orphanedNormalizedUrls = [];
+				
+				await foreach (FileUrl fileUrl in state.Db.Downloads.FindReachableFiles()) {
+					reachableNormalizedUrls.Add(fileUrl.NormalizedUrl);
+				}
+				
+				await foreach (Download download in state.Db.Downloads.Get()) {
+					string normalizedUrl = download.NormalizedUrl;
+					if (!reachableNormalizedUrls.Contains(normalizedUrl)) {
+						orphanedNormalizedUrls.Add(normalizedUrl);
+					}
+				}
+				
+				if (orphanedNormalizedUrls.Count == 0) {
+					await Dialog.ShowOk(window, Title, "No orphaned downloads found.");
+					return;
+				}
+				
+				if (await Dialog.ShowYesNo(window, Title, orphanedNormalizedUrls.Count + " orphaned download(s) will be removed from this database. This action cannot be undone. Proceed?") != DialogResult.YesNo.Yes) {
+					return;
+				}
+				
+				await callback.UpdateIndeterminate("Deleting orphaned downloads...");
+				await state.Db.Downloads.Remove(orphanedNormalizedUrls);
+				RecomputeDownloadStatistics();
+				
+				if (await Dialog.ShowYesNo(window, Title, "Orphaned downloads deleted. Vacuum database now to reclaim space?") != DialogResult.YesNo.Yes) {
+					return;
+				}
+				
+				await callback.UpdateIndeterminate("Vacuuming database...");
+				await state.Db.Vacuum();
+			});
+		} catch (Exception e) {
+			Log.Error("Could not delete orphaned downloads.", e);
+			await Dialog.ShowOk(window, Title, "Could not delete orphaned downloads: " + e.Message);
+		}
+	}
+	
+	public async Task OnClickExportAll() {
+		const string Title = "Export Downloaded Files";
+		
+		string[] folders = await window.StorageProvider.OpenFolders(new FolderPickerOpenOptions {
+			Title = Title,
+			AllowMultiple = false,
+		});
+		
+		if (folders.Length != 1) {
+			return;
+		}
+		
+		string folderPath = folders[0];
+		
+		DownloadExporter exporter = new DownloadExporter(state.Db, folderPath);
+		DownloadExporter.Result result;
+		try {
+			result = await ProgressDialog.Show(window, Title, async (_, callback) => {
+				await callback.UpdateIndeterminate("Exporting downloaded files...");
+				return await exporter.Export(new ExportProgressReporter(callback));
+			});
+		} catch (Exception e) {
+			Log.Error("Could not export downloaded files.", e);
+			await Dialog.ShowOk(window, Title, "Could not export downloaded files: " + e.Message);
+			return;
+		}
+		
+		string messageStart = "Exported " + result.SuccessfulCount.Pluralize("file");
+		
+		if (result.FailedCount > 0L) {
+			await Dialog.ShowOk(window, Title, messageStart + " (" + result.FailedCount.Format() + " failed).");
+		}
+		else {
+			await Dialog.ShowOk(window, Title, messageStart + ".");
+		}
+	}
+	
+	private sealed class ExportProgressReporter(IProgressCallback callback) : DownloadExporter.IProgressReporter {
+		public Task ReportProgress(long processedCount, long totalCount) {
+			return callback.Update("Exporting downloaded files...", processedCount, totalCount);
+		}
+	}
+	
+	private Task UpdateStatistics(DownloadStatusStatistics statusStatistics) {
 		statisticsPending.Items = statusStatistics.PendingCount;
 		statisticsPending.Size = statusStatistics.PendingTotalSize;
 		statisticsPending.HasFilesWithUnknownSize = statusStatistics.PendingWithUnknownSizeCount > 0;
@@ -175,24 +301,25 @@ sealed partial class DownloadsPageModel : ObservableObject, IAsyncDisposable {
 		statisticsSkipped.Size = statusStatistics.SkippedTotalSize;
 		statisticsSkipped.HasFilesWithUnknownSize = statusStatistics.SkippedWithUnknownSizeCount > 0;
 		
+		HasSuccessfulDownloads = statusStatistics.SuccessfulCount > 0;
 		HasFailedDownloads = statusStatistics.FailedCount > 0;
+		
+		return Task.CompletedTask;
 	}
 	
-	[ObservableObject]
 	public sealed partial class StatisticsRow(string state) {
 		public string State { get; } = state;
 		
-		[ObservableProperty]
+		[Notify]
 		private int items;
 		
-		[ObservableProperty]
+		[Notify]
-		[NotifyPropertyChangedFor(nameof(SizeText))]
 		private ulong? size;
 		
-		[ObservableProperty]
+		[Notify]
-		[NotifyPropertyChangedFor(nameof(SizeText))]
 		private bool hasFilesWithUnknownSize;
 		
+		[DependsOn(nameof(Size), nameof(HasFilesWithUnknownSize))]
 		public string SizeText {
 			get {
 				if (size == null) {

app/Desktop/Main/Pages/TrackingPage.axaml

@@ -11,17 +11,44 @@
         <pages:TrackingPageModel />
     </Design.DataContext>
 
-    <StackPanel Spacing="10">
+    <UserControl.Styles>
-        <TextBlock TextWrapping="Wrap">
+        <Style Selector="TextBlock">
-            To start tracking messages, copy the tracking script and paste it into the console of either the Discord app, or your browser. The console is usually opened by pressing Ctrl+Shift+I.
+            <Setter Property="TextWrapping" Value="Wrap" />
+        </Style>
+    </UserControl.Styles>
+
+    <StackPanel Spacing="20">
+        <Expander Header="Method 1: Manual" IsExpanded="True">
+            <StackPanel Orientation="Vertical" Spacing="10">
+                <TextBlock>
+                    <TextBlock.Text>
+                        <MultiBinding StringFormat="Use {0} to open Dev Tools in your browser or the Discord app, copy the tracking script, and paste it into the console.">
+                            <Binding Path="OpenDevToolsShortcutText" />
+                        </MultiBinding>
+                    </TextBlock.Text>
                 </TextBlock>
-        <StackPanel DockPanel.Dock="Left" Orientation="Horizontal" Spacing="10">
+                <Button x:Name="CopyTrackingScript" Click="CopyTrackingScriptButton_OnClick">Copy Tracking Script</Button>
-            <Button x:Name="CopyTrackingScript" Click="CopyTrackingScriptButton_OnClick" IsEnabled="{Binding IsCopyTrackingScriptButtonEnabled}">Copy Tracking Script</Button>
+                <TextBlock Margin="0 5 0 0">
+                    By default, the Discord app blocks the Dev Tools shortcut. The button below changes a hidden setting to unblock the shortcut.
+                </TextBlock>
+                <Button Command="{Binding OnClickToggleAppDevTools}" Content="{Binding ToggleAppDevToolsButtonText}" IsEnabled="{Binding IsToggleAppDevToolsButtonEnabled}" />
             </StackPanel>
-        <TextBlock TextWrapping="Wrap" Margin="0 5 0 0">
+        </Expander>
-            By default, the Discord app does not allow opening the console. The button below will change a hidden setting in the Discord app that controls whether the Ctrl+Shift+I shortcut is enabled.
+        <Expander Header="Method 2: Userscript" IsExpanded="True">
+            <StackPanel Orientation="Vertical" Spacing="10">
+                <TextBlock>
+                    Requires a userscript manager in your browser. The userscript adds a DHT icon next to the Help icon on Discord.
+                    If the icon does not appear, update this app and reinstall the userscript.
                 </TextBlock>
-        <Button DockPanel.Dock="Right" Command="{Binding OnClickToggleAppDevTools}" Content="{Binding ToggleAppDevToolsButtonText}" IsEnabled="{Binding IsToggleAppDevToolsButtonEnabled}" />
+                <TextBlock>
+                    Copy the Connection Code, click the DHT icon, and paste the code into the prompt.
+                </TextBlock>
+                <WrapPanel ItemSpacing="10" LineSpacing="10">
+                    <Button Command="{Binding OnClickInstallOrUpdateUserscript}">Install or Update Userscript</Button>
+                    <Button x:Name="CopyConnectionCode" Click="CopyConnectionScriptButton_OnClick">Copy Connection Code</Button>
+                </WrapPanel>
+            </StackPanel>
+        </Expander>
     </StackPanel>
 
 </UserControl>

app/Desktop/Main/Pages/TrackingPage.axaml.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Threading.Tasks;
 using Avalonia.Controls;
@@ -8,24 +9,36 @@ namespace DHT.Desktop.Main.Pages;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
 public sealed partial class TrackingPage : UserControl {
-	private bool isCopyingScript;
+	private readonly HashSet<Button> copyingButtons = new (ReferenceEqualityComparer.Instance);
 	
 	public TrackingPage() {
 		InitializeComponent();
 	}
 	
 	public async void CopyTrackingScriptButton_OnClick(object? sender, RoutedEventArgs e) {
+		await HandleCopyButton(CopyTrackingScript, "Script Copied!", static model => model.OnClickCopyTrackingScript());
+	}
+	
+	public async void CopyConnectionScriptButton_OnClick(object? sender, RoutedEventArgs e) {
+		await HandleCopyButton(CopyConnectionCode, "Code Copied!", static model => model.OnClickCopyConnectionCode());
+	}
+	
+	private async Task HandleCopyButton(Button button, string copiedText, Func<TrackingPageModel, Task<bool>> onClick) {
 		if (DataContext is TrackingPageModel model) {
-			var originalText = CopyTrackingScript.Content;
+			object? originalText = button.Content;
-			CopyTrackingScript.MinWidth = CopyTrackingScript.Bounds.Width;
+			button.MinWidth = button.Bounds.Width;
 			
-			if (await model.OnClickCopyTrackingScript() && !isCopyingScript) {
+			if (await onClick(model) && copyingButtons.Add(button)) {
-				isCopyingScript = true;
+				button.IsEnabled = false;
-				CopyTrackingScript.Content = "Script Copied!";
+				button.Content = copiedText;
 				
+				try {
 					await Task.Delay(TimeSpan.FromSeconds(2));
-				CopyTrackingScript.Content = originalText;
+				} finally {
-				isCopyingScript = false;
+					copyingButtons.Remove(button);
+					button.IsEnabled = true;
+					button.Content = originalText;
+				}
 			}
 		}
 	}

app/Desktop/Main/Pages/TrackingPageModel.cs

@@ -1,28 +1,32 @@
 using System;
+using System.Text.RegularExpressions;
 using System.Threading;
 using System.Threading.Tasks;
 using System.Web;
 using Avalonia.Controls;
-using CommunityToolkit.Mvvm.ComponentModel;
+using Avalonia.Input.Platform;
+using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Discord;
 using DHT.Desktop.Server;
+using DHT.Utils.Logging;
+using PropertyChanged.SourceGenerator;
 using static DHT.Desktop.Program;
 
 namespace DHT.Desktop.Main.Pages;
 
-sealed partial class TrackingPageModel : ObservableObject {
+sealed partial class TrackingPageModel {
-	[ObservableProperty(Setter = Access.Private)]
+	private static readonly Log Log = Log.ForType<TrackingPageModel>();
-	private bool isCopyTrackingScriptButtonEnabled = true;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
-	[NotifyPropertyChangedFor(nameof(ToggleAppDevToolsButtonText))]
 	private bool? areDevToolsEnabled = null;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
-	[NotifyPropertyChangedFor(nameof(ToggleAppDevToolsButtonText))]
 	private bool isToggleAppDevToolsButtonEnabled = false;
 	
+	public string OpenDevToolsShortcutText { get; } = OperatingSystem.IsMacOS() ? "Cmd+Shift+I" : "Ctrl+Shift+I";
+	
+	[DependsOn(nameof(AreDevToolsEnabled), nameof(IsToggleAppDevToolsButtonEnabled))]
 	public string ToggleAppDevToolsButtonText {
 		get {
 			if (!AreDevToolsEnabled.HasValue) {
@@ -33,7 +37,7 @@ sealed partial class TrackingPageModel : ObservableObject {
 				return "Unavailable";
 			}
 			
-			return AreDevToolsEnabled.Value ? "Disable Ctrl+Shift+I" : "Enable Ctrl+Shift+I";
+			return (AreDevToolsEnabled.Value ? "Disable" : "Enable") + " " + OpenDevToolsShortcutText;
 		}
 	}
 	
@@ -49,32 +53,9 @@ sealed partial class TrackingPageModel : ObservableObject {
 	}
 	
 	public async Task<bool> OnClickCopyTrackingScript() {
-		IsCopyTrackingScriptButtonEnabled = false;
+		string url = ServerConfiguration.HttpHost + $"/get-tracking-script?token={HttpUtility.UrlEncode(ServerConfiguration.Token)}";
-
-		try {
-			return await CopyTrackingScript();
-		} finally {
-			IsCopyTrackingScriptButtonEnabled = true;
-		}
-	}
-
-	private async Task<bool> CopyTrackingScript() {
-		string url = $"http://127.0.0.1:{ServerConfiguration.Port}/get-tracking-script?token={HttpUtility.UrlEncode(ServerConfiguration.Token)}";
 		string script = (await Resources.ReadTextAsync("tracker-loader.js")).Trim().Replace("{url}", url);
-
+		return await TryCopy(script, "Copy Tracking Script");
-		var clipboard = window.Clipboard;
-		if (clipboard == null) {
-			await Dialog.ShowOk(window, "Copy Tracking Script", "Clipboard is not available on this system.");
-			return false;
-		}
-
-		try {
-			await clipboard.SetTextAsync(script);
-			return true;
-		} catch {
-			await Dialog.ShowOk(window, "Copy Tracking Script", "An error occurred while copying to clipboard.");
-			return false;
-		}
 	}
 	
 	private async Task InitializeDevToolsToggle() {
@@ -102,11 +83,11 @@ sealed partial class TrackingPageModel : ObservableObject {
 		switch (await DiscordAppSettings.ConfigureDevTools(newState)) {
 			case SettingsJsonResult.Success:
 				AreDevToolsEnabled = newState;
-				await Dialog.ShowOk(window, DialogTitle, "Ctrl+Shift+I was " + (newState ? "enabled." : "disabled.") + " Restart the Discord app for the change to take effect.");
+				await Dialog.ShowOk(window, DialogTitle, OpenDevToolsShortcutText + " was " + (newState ? "enabled." : "disabled.") + " Restart the Discord app for the change to take effect.");
 				break;
 			
 			case SettingsJsonResult.AlreadySet:
-				await Dialog.ShowOk(window, DialogTitle, "Ctrl+Shift+I is already " + (newState ? "enabled." : "disabled."));
+				await Dialog.ShowOk(window, DialogTitle, OpenDevToolsShortcutText + " is already " + (newState ? "enabled." : "disabled."));
 				AreDevToolsEnabled = newState;
 				break;
 			
@@ -130,4 +111,44 @@ sealed partial class TrackingPageModel : ObservableObject {
 				throw new ArgumentOutOfRangeException();
 		}
 	}
+	
+	public async Task OnClickInstallOrUpdateUserscript() {
+		try {
+			SystemUtils.OpenUrl(ServerConfiguration.HttpHost + "/get-userscript/dht.user.js");
+		} catch (Exception e) {
+			await Dialog.ShowOk(window, "Install or Update Userscript", "Could not open the browser: " + e.Message);
+		}
+	}
+	
+	[GeneratedRegex("^[a-zA-Z0-9]{1,100}$")]
+	private static partial Regex ConnectionCodeTokenRegex();
+	
+	public async Task<bool> OnClickCopyConnectionCode() {
+		const string Title = "Copy Connection Code";
+		
+		if (ConnectionCodeTokenRegex().IsMatch(ServerConfiguration.Token)) {
+			return await TryCopy(ServerConfiguration.Port + ":" + ServerConfiguration.Token, Title);
+		}
+		else {
+			await Dialog.ShowOk(window, Title, "The internal server token cannot be used to create a connection code.\n\nCheck the 'Advanced' tab and ensure the token is 1-100 characters long, and only contains plain letters and numbers.");
+			return false;
+		}
+	}
+	
+	private async Task<bool> TryCopy(string script, string errorDialogTitle) {
+		IClipboard? clipboard = window.Clipboard;
+		if (clipboard == null) {
+			await Dialog.ShowOk(window, errorDialogTitle, "Clipboard is not available on this system.");
+			return false;
+		}
+		
+		try {
+			await clipboard.SetTextAsync(script);
+			return true;
+		} catch (Exception e) {
+			Log.Error("Could not copy to clipboard.", e);
+			await Dialog.ShowOk(window, errorDialogTitle, "An error occurred while copying to clipboard.");
+			return false;
+		}
+	}
 }

app/Desktop/Main/Pages/ViewerPageModel.cs

@@ -1,10 +1,8 @@
 using System;
 using System.ComponentModel;
-using System.Diagnostics;
 using System.Threading.Tasks;
 using System.Web;
 using Avalonia.Controls;
-using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Dialogs.Progress;
@@ -13,14 +11,18 @@ using DHT.Desktop.Server;
 using DHT.Server;
 using DHT.Server.Data.Filters;
 using DHT.Server.Service.Viewer;
+using DHT.Utils.Logging;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Pages;
 
-sealed partial class ViewerPageModel : ObservableObject, IDisposable {
+sealed partial class ViewerPageModel : IDisposable {
+	private static readonly Log Log = Log.ForType<ViewerPageModel>();
+	
 	public bool DatabaseToolFilterModeKeep { get; set; } = true;
 	public bool DatabaseToolFilterModeRemove { get; set; } = false;
 	
-	[ObservableProperty]
+	[Notify]
 	private bool hasFilters = false;
 	
 	public MessageFilterPanelModel FilterModel { get; }
@@ -49,21 +51,18 @@ sealed partial class ViewerPageModel : ObservableObject, IDisposable {
 	
 	public async void OnClickOpenViewer() {
 		try {
-			string serverUrl = "http://127.0.0.1:" + ServerConfiguration.Port;
 			string serverToken = ServerConfiguration.Token;
 			string sessionId = state.ViewerSessions.Register(new ViewerSession(FilterModel.CreateFilter())).ToString();
-			
+			SystemUtils.OpenUrl(ServerConfiguration.HttpHost + "/viewer/?token=" + HttpUtility.UrlEncode(serverToken) + "&session=" + HttpUtility.UrlEncode(sessionId));
-			Process.Start(new ProcessStartInfo(serverUrl + "/viewer/?token=" + HttpUtility.UrlEncode(serverToken) + "&session=" + HttpUtility.UrlEncode(sessionId)) {
-				UseShellExecute = true
-			});
 		} catch (Exception e) {
 			await Dialog.ShowOk(window, "Open Viewer", "Could not open viewer: " + e.Message);
 		}
 	}
 	
 	public async Task OnClickApplyFiltersToDatabase() {
-		var filter = FilterModel.CreateFilter();
+		try {
-		var messageCount = await ProgressDialog.ShowIndeterminate(window, "Apply Filters", "Counting matching messages...", _ => state.Db.Messages.Count(filter));
+			MessageFilter filter = FilterModel.CreateFilter();
+			long messageCount = await ProgressDialog.ShowIndeterminate(window, "Apply Filters", "Counting matching messages...", _ => state.Db.Messages.Count(filter));
 			
 			if (DatabaseToolFilterModeKeep) {
 				if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Keep Matching Messages in This Database", messageCount.Pluralize("message") + " will be kept, and the rest will be removed from this database. This action cannot be undone. Proceed?")) {
@@ -75,9 +74,28 @@ sealed partial class ViewerPageModel : ObservableObject, IDisposable {
 					await ApplyFilterToDatabase(filter, FilterRemovalMode.RemoveMatching);
 				}
 			}
+		} catch (Exception e) {
+			Log.Error("Could not apply filters.", e);
+			await Dialog.ShowOk(window, "Apply Filters", "Could not apply filters: " + e.Message);
+		}
 	}
 	
 	private async Task ApplyFilterToDatabase(MessageFilter filter, FilterRemovalMode removalMode) {
-		await ProgressDialog.ShowIndeterminate(window, "Apply Filters", "Removing messages...", _ => state.Db.Messages.Remove(filter, removalMode));
+		await ProgressDialog.Show(window, "Apply Filters", async (_, callback) => {
+			await callback.UpdateIndeterminate("Removing messages...");
+			Log.Info("Removed messages: " + await state.Db.Messages.Remove(filter, removalMode));
+			
+			await callback.UpdateIndeterminate("Cleaning up attachments...");
+			Log.Info("Removed orphaned attachments: " + await state.Db.Messages.RemoveUnreachableAttachments());
+			
+			await callback.UpdateIndeterminate("Cleaning up users...");
+			Log.Info("Removed orphaned users: " + await state.Db.Users.RemoveUnreachable());
+			
+			await callback.UpdateIndeterminate("Cleaning up channels...");
+			Log.Info("Removed orphaned channels: " + await state.Db.Channels.RemoveUnreachable());
+			
+			await callback.UpdateIndeterminate("Cleaning up servers...");
+			Log.Info("Removed orphaned servers: " + await state.Db.Servers.RemoveUnreachable());
+		});
 	}
 }

app/Desktop/Main/Screens/MainContentScreen.axaml

@@ -40,13 +40,13 @@
         <Style Selector="TabItem:pointerover /template/ Border">
             <Setter Property="Background" Value="#455785" />
         </Style>
-        <Style Selector="TabItem:pointerover > TextBlock">
+        <Style Selector="TabItem:pointerover /template/ ContentPresenter">
             <Setter Property="Foreground" Value="#E9E9E9" />
         </Style>
         <Style Selector="TabItem:selected:pointerover /template/ Border">
             <Setter Property="Background" Value="#FFFFFF" />
         </Style>
-        <Style Selector="TabItem:selected:pointerover > TextBlock">
+        <Style Selector="TabItem:selected:pointerover /template/ ContentPresenter">
             <Setter Property="Foreground" Value="#1A2234" />
         </Style>
         <Style Selector="TabItem:selected">
@@ -56,9 +56,11 @@
         <Style Selector="TabItem:selected /template/ Border#PART_SelectedPipe">
             <Setter Property="IsVisible" Value="False" />
         </Style>
-        <Style Selector="TabItem:disabled > TextBlock">
+        <Style Selector="TabItem:disabled /template/ ContentPresenter">
             <Setter Property="Foreground" Value="#B2B2B2" />
-            <Setter Property="TextDecorations" Value="Strikethrough" />
+        </Style>
+        <Style Selector="TabItem:disabled /template/ ContentPresenter">
+            <Setter Property="AccessText.TextDecorations" Value="Strikethrough" />
         </Style>
         <Style Selector="TabItem.first">
             <Setter Property="Margin" Value="0 13 0 0" />

app/Desktop/Main/Screens/MainContentScreenModel.cs

@@ -35,12 +35,8 @@ sealed class MainContentScreenModel : IAsyncDisposable {
 	public StatusBarModel StatusBarModel { get; }
 	
 	public event EventHandler? DatabaseClosed {
-		add {
+		add => DatabasePageModel.DatabaseClosed += value;
-			DatabasePageModel.DatabaseClosed += value;
+		remove => DatabasePageModel.DatabaseClosed -= value;
-		}
-		remove {
-			DatabasePageModel.DatabaseClosed -= value;
-		}
 	}
 	
 	[Obsolete("Designer")]
@@ -53,7 +49,7 @@ sealed class MainContentScreenModel : IAsyncDisposable {
 		TrackingPageModel = new TrackingPageModel(window);
 		TrackingPage = new TrackingPage { DataContext = TrackingPageModel };
 		
-		DownloadsPageModel = new DownloadsPageModel(state);
+		DownloadsPageModel = new DownloadsPageModel(window, state);
 		DownloadsPage = new DownloadsPage { DataContext = DownloadsPageModel };
 		
 		ViewerPageModel = new ViewerPageModel(window, state);
@@ -74,6 +70,10 @@ sealed class MainContentScreenModel : IAsyncDisposable {
 	
 	public async Task Initialize() {
 		await DownloadsPageModel.Initialize();
+		
+		#if DEBUG
+		await DebugPageModel.Initialize();
+		#endif
 	}
 	
 	public async ValueTask DisposeAsync() {

app/Desktop/Main/Screens/WelcomeScreen.axaml

@@ -22,20 +22,21 @@
             <Setter Property="HorizontalAlignment" Value="Center" />
             <Setter Property="VerticalAlignment" Value="Center" />
         </Style>
-        <Style Selector="Button">
+        <Style Selector="Grid#ButtonPanel > Button">
-            <Setter Property="Margin" Value="5 0" />
+            <Setter Property="HorizontalAlignment" Value="Stretch" />
         </Style>
     </UserControl.Styles>
 
     <Panel Name="RootPanel">
-        <StackPanel Margin="42">
+        <StackPanel Margin="42 30">
-            <TextBlock Text="{Binding Version, StringFormat=Discord History Tracker v{0}}" FontSize="25" Margin="0 0 0 30" HorizontalAlignment="Center" />
+            <TextBlock Text="{Binding Version, StringFormat=Discord History Tracker v{0}}" FontSize="25" Margin="0 0 0 25" HorizontalAlignment="Center" />
 
-            <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
+            <Grid Name="ButtonPanel" RowDefinitions="Auto,12,Auto,12,Auto" ColumnDefinitions="*,12,*" Margin="12 0" HorizontalAlignment="Stretch">
-                <Button Command="{Binding OpenOrCreateDatabase}" IsEnabled="{Binding IsOpenOrCreateDatabaseButtonEnabled}">Open or Create Database</Button>
+                <Button Grid.Row="0" Grid.Column="0" Grid.ColumnSpan="3" Command="{Binding OpenOrCreateDatabase}" IsEnabled="{Binding IsOpenOrCreateDatabaseButtonEnabled}">Open or Create Database</Button>
-                <Button Command="{Binding ShowAboutDialog}">About</Button>
+                <Button Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="3" Command="{Binding CheckUpdates}">Check For Updates</Button>
-                <Button Command="{Binding Exit}">Exit</Button>
+                <Button Grid.Row="4" Grid.Column="0" Command="{Binding ShowAboutDialog}">About</Button>
-            </StackPanel>
+                <Button Grid.Row="4" Grid.Column="2" Command="{Binding Exit}">Exit</Button>
+            </Grid>
         </StackPanel>
     </Panel>
 </UserControl>

app/Desktop/Main/Screens/WelcomeScreenModel.cs

@@ -1,22 +1,28 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using System.Net;
+using System.Net.Http;
 using System.Threading.Tasks;
 using Avalonia.Controls;
-using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Dialogs.Progress;
-using DHT.Server.Data.Settings;
+using DHT.Desktop.Main.Dialogs;
 using DHT.Server.Database;
 using DHT.Server.Database.Sqlite.Schema;
+using DHT.Server.Database.Sqlite.Utils;
+using DHT.Utils.Logging;
+using PropertyChanged.SourceGenerator;
 
 namespace DHT.Desktop.Main.Screens;
 
-sealed partial class WelcomeScreenModel : ObservableObject {
+sealed partial class WelcomeScreenModel {
+	private static readonly Log Log = Log.ForType<WelcomeScreenModel>();
+	
 	public string Version => Program.Version;
 	
-	[ObservableProperty(Setter = Access.Private)]
+	[Notify(Setter.Private)]
 	private bool isOpenOrCreateDatabaseButtonEnabled = true;
 	
 	public event EventHandler<IDatabaseFile>? DatabaseSelected;
@@ -35,7 +41,7 @@ sealed partial class WelcomeScreenModel : ObservableObject {
 	public async Task OpenOrCreateDatabase() {
 		IsOpenOrCreateDatabaseButtonEnabled = false;
 		try {
-			var path = await DatabaseGui.NewOpenOrCreateDatabaseFileDialog(window, Path.GetDirectoryName(dbFilePath));
+			string? path = await DatabaseGui.NewOpenOrCreateDatabaseFileDialog(window, Path.GetDirectoryName(dbFilePath));
 			if (path != null) {
 				await OpenOrCreateDatabaseFromPath(path);
 			}
@@ -47,25 +53,20 @@ sealed partial class WelcomeScreenModel : ObservableObject {
 	public async Task OpenOrCreateDatabaseFromPath(string path) {
 		dbFilePath = path;
 		
-		bool isNew = !File.Exists(path);
+		IDatabaseFile? db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, window, new SchemaUpgradeCallbacks(window));
-		
+		if (db != null) {
-		var db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, window, new SchemaUpgradeCallbacks(window));
-		if (db == null) {
-			return;
-		}
-		
-		if (isNew && await Dialog.ShowYesNo(window, "Automatic Downloads", "Do you want to automatically download files hosted on Discord? You can change this later in the Downloads tab.") == DialogResult.YesNo.Yes) {
-			await db.Settings.Set(SettingsKey.DownloadsAutoStart, true);
-		}
-		
 			DatabaseSelected?.Invoke(this, db);
 		}
+	}
 	
-	private sealed class SchemaUpgradeCallbacks : ISchemaUpgradeCallbacks {
+	private sealed class SchemaUpgradeCallbacks(Window window) : ISchemaUpgradeCallbacks {
-		private readonly Window window;
+		public async Task<InitialDatabaseSettings?> GetInitialDatabaseSettings() {
+			var model = new NewDatabaseSettingsDialogModel();
 			
-		public SchemaUpgradeCallbacks(Window window) {
+			var dialog = new NewDatabaseSettingsDialog { DataContext = model };
-			this.window = window;
+			await dialog.ShowDialog(window);
+			
+			return new InitialDatabaseSettings(model.SeparateFileForDownloads, model.DownloadsAutoStart);
 		}
 		
 		public async Task<bool> CanUpgrade() {
@@ -84,17 +85,9 @@ sealed partial class WelcomeScreenModel : ObservableObject {
 			await new ProgressDialog { DataContext = new ProgressDialogModel("Upgrading Database", StartUpgrade, progressItems: 3) }.ShowProgressDialog(window);
 		}
 		
-		private sealed class ProgressReporter : ISchemaUpgradeCallbacks.IProgressReporter {
+		private sealed class ProgressReporter(int versionSteps, IReadOnlyList<IProgressCallback> callbacks) : ISchemaUpgradeCallbacks.IProgressReporter {
-			private readonly IReadOnlyList<IProgressCallback> callbacks;
-			
-			private readonly int versionSteps;
 			private int versionProgress = 0;
 			
-			public ProgressReporter(int versionSteps, IReadOnlyList<IProgressCallback> callbacks) {
-				this.callbacks = callbacks;
-				this.versionSteps = versionSteps;
-			}
-
 			public async Task NextVersion() {
 				await callbacks[0].Update("Upgrading schema version...", versionProgress++, versionSteps);
 				await HideChildren(0);
@@ -118,6 +111,47 @@ sealed partial class WelcomeScreenModel : ObservableObject {
 		}
 	}
 	
+	public async Task CheckUpdates() {
+		string response;
+		try {
+			response = await ProgressDialog.ShowIndeterminate<string>(window, "Check Updates", "Checking for updates...", static async _ => {
+				var client = new HttpClient(new SocketsHttpHandler {
+					AutomaticDecompression = DecompressionMethods.None,
+					AllowAutoRedirect = false,
+					UseCookies = false,
+				});
+				
+				client.Timeout = TimeSpan.FromSeconds(30);
+				client.MaxResponseContentBufferSize = 1024;
+				client.DefaultRequestHeaders.UserAgent.ParseAdd("DiscordHistoryTracker/" + Program.Version);
+				
+				return await client.GetStringAsync(Program.Website + "/version");
+			});
+		} catch (TaskCanceledException e) when (e.InnerException is TimeoutException) {
+			await Dialog.ShowOk(window, "Check Updates", "Request timed out.");
+			return;
+		} catch (Exception e) {
+			Log.Error("Could not check for updates.", e);
+			await Dialog.ShowOk(window, "Check Updates", "Error checking for updates: " + e.Message);
+			return;
+		}
+		
+		if (!System.Version.TryParse(response, out Version? latestVersion)) {
+			await Dialog.ShowOk(window, "Check Updates", "Server returned an invalid response.");
+			return;
+		}
+		
+		if (Program.AssemblyVersion >= latestVersion) {
+			await Dialog.ShowOk(window, "Check Updates", "You are using the latest version.");
+			return;
+		}
+		
+		if (await Dialog.ShowYesNo(window, "Check Updates", "A newer version is available: v" + Program.VersionToString(latestVersion) + "\nVisit the official website and close the app?") == DialogResult.YesNo.Yes) {
+			SystemUtils.OpenUrl(Program.Website);
+			Exit();
+		}
+	}
+	
 	public async Task ShowAboutDialog() {
 		await new AboutWindow { DataContext = new AboutWindowModel() }.ShowDialog(window);
 	}

app/Desktop/Program.cs

@@ -2,6 +2,7 @@
 using System.Globalization;
 using System.Reflection;
 using Avalonia;
+using DHT.Desktop.Common;
 using DHT.Utils.Logging;
 using DHT.Utils.Resources;
 
@@ -9,17 +10,18 @@ namespace DHT.Desktop;
 
 static class Program {
 	public static string Version { get; }
+	public static Version AssemblyVersion { get; }
 	public static CultureInfo Culture { get; }
 	public static ResourceLoader Resources { get; }
 	public static Arguments Arguments { get; }
 	
+	public const string Website = "https://dht.chylex.com";
+	
 	static Program() {
 		var assembly = Assembly.GetExecutingAssembly();
 		
-		Version = assembly.GetName().Version?.ToString() ?? "";
+		AssemblyVersion = assembly.GetName().Version ?? new Version(major: 0, minor: 0, build: 0, revision: 0);
-		while (Version.EndsWith(".0")) {
+		Version = VersionToString(AssemblyVersion);
-			Version = Version[..^2];
-		}
 		
 		Culture = CultureInfo.CurrentCulture;
 		CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
@@ -31,6 +33,16 @@ static class Program {
 		Arguments = new Arguments(Environment.GetCommandLineArgs());
 	}
 	
+	public static string VersionToString(Version version) {
+		string versionStr = version.ToString();
+		
+		while (versionStr.EndsWith(".0")) {
+			versionStr = versionStr[..^2];
+		}
+		
+		return versionStr;
+	}
+	
 	public static void Main(string[] args) {
 		if (Arguments.Console && OperatingSystem.IsWindows()) {
 			WindowsConsole.AllocConsole();
@@ -46,6 +58,8 @@ static class Program {
 	}
 	
 	private static AppBuilder BuildAvaloniaApp() {
+		AvaloniaReflection.Check();
+		
 		return AppBuilder.Configure<App>()
 		                 .UsePlatformDetect()
 		                 .WithInterFont()

app/Desktop/Server/ServerConfiguration.cs

@@ -3,6 +3,8 @@ using DHT.Server.Service;
 namespace DHT.Desktop.Server;
 
 static class ServerConfiguration {
-	public static ushort Port { get; set; } = ServerUtils.FindAvailablePort(50000, 60000);
+	public static ushort Port { get; set; } = ServerUtils.FindAvailablePort(min: 50000, max: 60000);
 	public static string Token { get; set; } = ServerUtils.GenerateRandomToken(20);
+	
+	public static string HttpHost => "http://127.0.0.1:" + Port;
 }

app/Directory.Build.props

@@ -1,8 +1,8 @@
 <Project>
   
   <PropertyGroup>
-    <TargetFramework>net8.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
-    <LangVersion>12</LangVersion>
+    <LangVersion>13</LangVersion>
     <Nullable>enable</Nullable>
   </PropertyGroup>
   
@@ -21,12 +21,13 @@
   <PropertyGroup>
     <SuppressTrimAnalysisWarnings>false</SuppressTrimAnalysisWarnings>
     <PublishTrimmed>true</PublishTrimmed>
-    <TrimMode>partial</TrimMode>
+    <TrimMode>full</TrimMode>
     <EnableUnsafeBinaryFormatterSerialization>false</EnableUnsafeBinaryFormatterSerialization>
     <EnableUnsafeUTF7Encoding>false</EnableUnsafeUTF7Encoding>
     <EventSourceSupport>false</EventSourceSupport>
     <HttpActivityPropagationSupport>false</HttpActivityPropagationSupport>
     <JsonSerializerIsReflectionEnabledByDefault>false</JsonSerializerIsReflectionEnabledByDefault>
+    <XmlResolverIsNetworkingEnabledByDefault>false</XmlResolverIsNetworkingEnabledByDefault>
   </PropertyGroup>
   
   <PropertyGroup>
@@ -39,6 +40,7 @@
   <PropertyGroup Condition=" '$(Configuration)' == 'Release' ">
     <DebugSymbols>false</DebugSymbols>
     <DebugType>none</DebugType>
+    <ContinuousIntegrationBuild>true</ContinuousIntegrationBuild>
   </PropertyGroup>
   
   <PropertyGroup>

app/Resources/Tracker/bootstrap.js

@@ -10,11 +10,16 @@
 		return;
 	}
 	
+	/*[IMPORTS]*/
+	
+	if (!DISCORD.isCompatible()) {
+		alert("Discord History Tracker is not compatible with this version of Discord.");
+		return;
+	}
+	
 	window.DHT_LOADED = true;
 	window.DHT_ON_UNLOAD = [];
 	
-	/*[IMPORTS]*/
-	
 	const port = 0; /*[PORT]*/
 	const token = "/*[TOKEN]*/";
 	STATE.setup(port, token);
@@ -46,7 +51,7 @@
 		return action === null || action === CONSTANTS.AUTOSCROLL_ACTION_NOTHING;
 	};
 	
-	const onTrackingContinued = function(anyNewMessages) {
+	const onTrackingContinued = function(anyNewMessages, hasMoreBefore) {
 		if (!STATE.isTracking()) {
 			return;
 		}
@@ -63,7 +68,7 @@
 		if (SETTINGS.autoscroll) {
 			let action = null;
 			
-			if (!DISCORD.hasMoreMessages()) {
+			if (!hasMoreBefore) {
 				console.debug("[DHT] Reached first message.");
 				action = SETTINGS.afterFirstMsg;
 			}
@@ -84,7 +89,7 @@
 	
 	let waitUntilSendingFinishedTimer = null;
 	
-	const onMessagesUpdated = async messages => {
+	const onMessagesUpdated = async (server, channel, messages, hasMoreBefore) => {
 		if (!STATE.isTracking() || delayedStopRequests > 0) {
 			return;
 		}
@@ -94,24 +99,16 @@
 			
 			waitUntilSendingFinishedTimer = window.setTimeout(() => {
 				waitUntilSendingFinishedTimer = null;
-				onMessagesUpdated(messages);
+				onMessagesUpdated(server, channel, messages, hasMoreBefore);
 			}, 100);
 			
 			return;
 		}
 		
-		const info = DISCORD.getSelectedChannel();
-		
-		if (!info) {
-			GUI.setStatus("Error (Unknown Channel)");
-			stopTrackingDelayed();
-			return;
-		}
-		
 		isSending = true;
 		
 		try {
-			await STATE.addDiscordChannel(info.server, info.channel);
+			await STATE.addDiscordChannel(server, channel);
 		} catch (e) {
 			onError(e);
 			return;
@@ -120,35 +117,33 @@
 		try {
 			if (!messages.length) {
 				isSending = false;
-				onTrackingContinued(false);
+				onTrackingContinued(false, hasMoreBefore);
 			}
 			else {
 				const anyNewMessages = await STATE.addDiscordMessages(messages);
-				onTrackingContinued(anyNewMessages);
+				onTrackingContinued(anyNewMessages, hasMoreBefore);
 			}
 		} catch (e) {
 			onError(e);
 		}
 	};
 	
-	DISCORD.setupMessageCallback(onMessagesUpdated);
+	const starter = DISCORD.setupMessageCallback(onMessagesUpdated);
 	
 	STATE.onTrackingStateChanged(enabled => {
 		if (enabled) {
-			const messages = DISCORD.getMessages();
-			
-			if (messages.length === 0) {
-				stopTrackingDelayed(() => alert("Cannot see any messages."));
-				return;
-			}
-			
 			GUI.setStatus("Starting");
+			GUI.createTrackingStyles();
 			hasJustStarted = true;
-			// noinspection JSIgnoredPromiseFromCall
+			
-			onMessagesUpdated(messages);
+			if (!starter()) {
+				stopTrackingDelayed(() => alert("Cannot see any messages."));
+				hasJustStarted = false;
+			}
 		}
 		else {
 			isSending = false;
+			GUI.deleteTrackingStyles();
 		}
 	});
 	

app/Resources/Tracker/loader/dht.user.js

@@ -0,0 +1,273 @@
+// ==UserScript==
+// @name         Discord History Tracker
+// @license      MIT
+// @namespace    https://chylex.com
+// @homepageURL  https://dht.chylex.com/
+// @supportURL   https://github.com/chylex/Discord-History-Tracker/issues
+// @include      https://discord.com/*
+// @run-at       document-idle
+// @grant        none
+// @noframes
+// ==/UserScript==
+
+function startMutationObserver(callback) {
+	let hasDebounceStarted = false;
+	
+	function handleMutations(mutations, observer) {
+		if (hasDebounceStarted) {
+			return;
+		}
+		
+		hasDebounceStarted = true;
+		window.setTimeout(() => {
+			hasDebounceStarted = false;
+			callback(observer);
+		}, 20);
+	}
+	
+	new MutationObserver(handleMutations).observe(document.body, { childList: true, subtree: true });
+}
+
+startMutationObserver(observer => {
+	const triggerButton = installConnectDialogButton();
+	if (triggerButton === null) {
+		return;
+	}
+	
+	observer.disconnect();
+	
+	startMutationObserver(() => {
+		if (!triggerButton.isConnected) {
+			getHelpIcon()?.parentElement.parentElement.insertAdjacentElement("afterend", triggerButton);
+		}
+	});
+});
+
+function installConnectDialogButton() {
+	const helpIcon = getHelpIcon();
+	if (!helpIcon) {
+		return null;
+	}
+	
+	const helpIconWrapper = helpIcon.parentElement;
+	const helpIconLink = helpIconWrapper.parentElement;
+	
+	helpIconLink.insertAdjacentHTML("afterend", `
+<div id="dht-connector-show-dialog" role="button" class="${helpIconWrapper.getAttribute("class")}">
+  <svg viewBox="0 0 24 20" fill="currentColor" class="${helpIcon.getAttribute("class")}" style="width: auto;">
+    <path d="M7.446,9.924c-0,0.846 -0.105,1.593 -0.315,2.234c-0.21,0.644 -0.497,1.181 -0.86,1.615c-0.365,0.431 -0.795,0.761 -1.292,0.982c-0.494,0.22 -1.029,0.332 -1.605,0.332l-3.374,-0l0,-10.174l3.021,0c0.645,0 1.239,0.1 1.781,0.296c0.542,0.198 1.011,0.501 1.4,0.911c0.391,0.408 0.695,0.928 0.914,1.56c0.22,0.629 0.33,1.378 0.33,2.244Zm-1.765,-0c0,-0.592 -0.067,-1.1 -0.198,-1.524c-0.134,-0.422 -0.318,-0.77 -0.554,-1.042c-0.236,-0.272 -0.518,-0.473 -0.848,-0.604c-0.332,-0.128 -0.697,-0.195 -1.096,-0.195l-1.237,-0l0,6.882l1.483,0c0.351,0 0.676,-0.076 0.977,-0.224c0.298,-0.15 0.556,-0.372 0.776,-0.668c0.22,-0.295 0.389,-0.663 0.513,-1.101c0.122,-0.439 0.184,-0.947 0.184,-1.524Z"/>
+    <path d="M14.147,15.087l-0,-4.362l-3.637,-0l-0,4.362l-1.748,-0l-0,-10.174l1.748,0l-0,4.052l3.637,-0l-0,-4.052l1.75,0l0,10.174l-1.75,-0Z"/>
+    <path d="M21.297,6.559l-0,8.528l-1.748,-0l-0,-8.528l-2.699,-0l0,-1.646l7.15,0l0,1.646l-2.703,-0Z"/>
+  </svg>
+</div>
+`);
+	
+	const button = document.getElementById("dht-connector-show-dialog");
+	button.addEventListener("click", showConnectDialog);
+	return button;
+}
+
+function getHelpIcon() {
+	return document.querySelector("div[class*='bar_'] a[href$='://support.discord.com'] > div[class*='clickable'] > svg");
+}
+
+function showConnectDialog() {
+	if (window.DHT_LOADED) {
+		alert("Discord History Tracker is already loaded.");
+		return;
+	}
+	
+	const dialogElement = document.createElement("dialog");
+	dialogElement.id = "dht-connector-dialog";
+	dialogElement.innerHTML = `
+<form id="dht-connector-dialog-form">
+  <label for="dht-connector-dialog-input-code">Connection Code</label>
+  <input id="dht-connector-dialog-input-code" type="text">
+  <p id="dht-connector-dialog-input-error"></p>
+  
+  <div id="dht-connector-dialog-buttons">
+    <button type="submit" id="dht-connector-dialog-button-connect">Connect</button>
+    <button type="button" id="dht-connector-dialog-button-close">Cancel</button>
+  </div>
+</form>
+<style>
+  #dht-connector-dialog {
+    width: 300px;
+    padding: 18px;
+    font-size: 16px;
+    border: none;
+    border-radius: 8px;
+    background-color: #313338;
+  }
+  
+  #dht-connector-dialog::backdrop {
+    background-color: rgba(0, 0, 0, 0.6);
+  }
+  
+  #dht-connector-dialog label {
+    display: block;
+    margin: 0 0 9px;
+    font-weight: 500;
+    letter-spacing: .02em;
+    color: #fbfbfb;
+  }
+  
+  #dht-connector-dialog-input-error {
+    margin: 11px 1px;
+    color: #ff484c;
+    font-size: 15px;
+    font-weight: 500;
+  }
+  
+  #dht-connector-dialog input[type="text"] {
+    box-sizing: border-box;
+    width: 100%;
+    padding: 12px 10px;
+    border: 1px solid rgba(151, 151, 159, 0.2);
+    border-radius: 8px;
+    color: #efeff0;
+    background-color: #1d1d21;
+  }
+  
+  #dht-connector-dialog-buttons {
+    margin-top: 15px;
+    display: flex;
+    justify-content: end;
+    gap: 12px;
+  }
+  
+  #dht-connector-dialog button {
+    padding: 8px 16px;
+    border: none;
+    border-radius: 8px;
+    font-size: 14px;
+    font-weight: 500;
+    color: #fff;
+    background-color: #5865f2;
+    transition: background-color 200ms ease, color 200ms ease;
+  }
+  
+  #dht-connector-dialog button:hover {
+    background-color: #4752c4;
+  }
+  
+  #dht-connector-dialog button[disabled] {
+    cursor: not-allowed;
+    opacity: 0.5;
+  }
+</style>
+	`;
+	
+	document.body.insertAdjacentElement("beforeend", dialogElement);
+	
+	const formElement = document.getElementById("dht-connector-dialog-form");
+	const codeErrorElement = document.getElementById("dht-connector-dialog-input-error");
+	const codeInputElement = document.getElementById("dht-connector-dialog-input-code");
+	const connectButtonElement = document.getElementById("dht-connector-dialog-button-connect");
+	const closeButtonElement = document.getElementById("dht-connector-dialog-button-close");
+	
+	dialogElement.addEventListener("close", function() {
+		dialogElement.remove();
+	});
+	
+	closeButtonElement.addEventListener("click", function() {
+		dialogElement.close();
+	});
+	
+	codeInputElement.addEventListener("paste", function() {
+		setTimeout(async function() {
+			const code = parseConnectionCode(codeInputElement.value);
+			if (code !== null) {
+				await onSubmit(code);
+			}
+		}, 0);
+	});
+	
+	formElement.addEventListener("submit", async function(e) {
+		e.preventDefault();
+		
+		const code = parseConnectionCode(codeInputElement.value);
+		if (code === null) {
+			codeErrorElement.innerText = "Code is not valid.";
+		}
+		else {
+			await onSubmit(code);
+		}
+	});
+	
+	let isSubmitting = false;
+	
+	async function onSubmit(code) {
+		if (isSubmitting) {
+			return;
+		}
+		
+		isSubmitting = true;
+		connectButtonElement.setAttribute("disabled", "");
+		try {
+			await loadTrackingScript(code);
+		} catch (e) {
+			onError("Could not load tracking script.", e);
+		} finally {
+			isSubmitting = false;
+			connectButtonElement.removeAttribute("disabled");
+		}
+	}
+	
+	async function loadTrackingScript(code) {
+		const trackingScript = await getTrackingScript(code.port, code.token);
+		
+		if (dialogElement.isConnected) {
+			// noinspection DynamicallyGeneratedCodeJS
+			eval(trackingScript);
+			dialogElement.close();
+		}
+	}
+	
+	function onError(message, e) {
+		console.error(message, e);
+		codeErrorElement.innerText = message;
+	}
+	
+	dialogElement.showModal();
+}
+
+/**
+ * @param {string} code
+ * @return {?{port: number, token: string}}
+ */
+function parseConnectionCode(code) {
+	if (code.length > 5 + 1 + 100) {
+		return null;
+	}
+	
+	const match = code.match(/^(\d{1,5}):([a-zA-Z0-9]{1,100})$/);
+	if (!match) {
+		return null;
+	}
+	
+	const port = Number(match[1]);
+	if (port < 0 || port > 65535) {
+		return null;
+	}
+	
+	return { port, token: match[2] };
+}
+
+async function getTrackingScript(port, token) {
+	const url = "http://127.0.0.1:" + port + "/get-tracking-script?token=" + encodeURIComponent(token);
+	const response = await fetch(url, {
+		credentials: "omit",
+		signal: AbortSignal.timeout(2000),
+	});
+	
+	if (!response.ok) {
+		throw response.status + " " + response.statusText;
+	}
+	
+	if (response.headers.get("X-DHT") !== "1") {
+		throw "Invalid response";
+	}
+	
+	return await response.text();
+}

app/Resources/Tracker/scripts/discord.js

@@ -4,11 +4,26 @@ class DISCORD {
 	
 	// https://discord.com/developers/docs/resources/channel#channel-object-channel-types
 	static CHANNEL_TYPE = {
+		GUILD_TEXT: 0,
 		DM: 1,
 		GROUP_DM: 3,
+		GUILD_ANNOUNCEMENT: 5,
 		ANNOUNCEMENT_THREAD: 10,
 		PUBLIC_THREAD: 11,
-		PRIVATE_THREAD: 12
+		PRIVATE_THREAD: 12,
+		
+		isPrivate(type) {
+			return type === this.DM
+				|| type === this.GROUP_DM;
+		},
+		
+		isNavigableGuildChannel(type) {
+			return type === this.GUILD_TEXT
+				|| type === this.GUILD_ANNOUNCEMENT
+				|| type === this.ANNOUNCEMENT_THREAD
+				|| type === this.PUBLIC_THREAD
+				|| type === this.PRIVATE_THREAD;
+		}
 	};
 	
 	// https://discord.com/developers/docs/resources/channel#message-object-message-types
@@ -18,6 +33,74 @@ class DISCORD {
 		THREAD_STARTER: 21
 	};
 	
+	// https://discord.com/developers/docs/topics/permissions#permissions-bitwise-permission-flags
+	static PERMISSION = {
+		VIEW_CHANNEL: 1n << 10n
+	};
+	
+	/**
+	 * @type {Object}
+	 * @property {function(String): ?DiscordGuild} getGuild
+	 */
+	static #guildStore = WEBPACK.findModule("guildStore", WEBPACK.filterByProps("getGuild", "getGuilds", "getGuildIds"));
+	
+	/**
+	 * @type {Object}
+	 * @property {function(String): Boolean} isOptInEnabled
+	 * @property {function(String): Set<String>} getOptedInChannels
+	 */
+	static #guildSettings = WEBPACK.findModule("guildSettings", WEBPACK.filterByProps("isOptInEnabled", "getOptedInChannels"));
+	
+	/**
+	 * @type {Object}
+	 * @property {function(String): ?DiscordChannel} getChannel
+	 * @property {function(String): Array<DiscordChannel>} getMutableGuildChannelsForGuild
+	 * @property {function(): Array<DiscordChannel>} getSortedPrivateChannels
+	 */
+	static #channelStore = WEBPACK.findModule("channelStore", WEBPACK.filterByProps("getChannel", "getMutableGuildChannelsForGuild", "getSortedPrivateChannels"));
+	
+	/**
+	 * @type {function(BigInt, Object): Boolean}
+	 */
+	static #hasPermission = WEBPACK.findFunction("can", [ "getGuildPermissions", "getChannelPermissions" ]);
+	
+	/**
+	 * @type {function(String): MessageData}
+	 */
+	static #getMessages = WEBPACK.findFunction("getMessages", [ "isLoadingMessages" ]);
+	
+	/**
+	 * @type {function(String): void}
+	 */
+	static #jumpToMessage = WEBPACK.findFunction("jumpToMessage");
+	
+	/**
+	 * @type {function(): String}
+	 */
+	static #getCurrentlySelectedChannelId = WEBPACK.findFunction("getCurrentlySelectedChannelId");
+	
+	/**
+	 * @type {function(String): void}
+	 */
+	static #selectPrivateChannel = WEBPACK.findFunction("selectPrivateChannel", [ "selectChannel" ]);
+	
+	/**
+	 * @type {function(String, Object, String=null): void}
+	 */
+	static #transitionToGuildSync = WEBPACK.findFunction("transitionToGuildSync");
+	
+	static isCompatible() {
+		return !!this.#guildStore
+			&& !!this.#guildSettings
+			&& !!this.#channelStore
+			&& !!this.#hasPermission
+			&& !!this.#getMessages
+			&& !!this.#jumpToMessage
+			&& !!this.#getCurrentlySelectedChannelId
+			&& !!this.#selectPrivateChannel
+			&& !!this.#transitionToGuildSync;
+	}
+	
 	static getMessageOuterElement() {
 		return DOM.queryReactClass("messagesWrapper");
 	}
@@ -26,14 +109,6 @@ class DISCORD {
 		return DOM.queryReactClass("scroller", this.getMessageOuterElement());
 	}
 	
-	static getMessageElements() {
-		return this.getMessageOuterElement().querySelectorAll("[class*='message_']");
-	}
-	
-	static hasMoreMessages() {
-		return document.querySelector("#messagesNavigationDescription + [class^=container]") === null;
-	}
-	
 	static loadOlderMessages() {
 		const view = this.getMessageScrollerElement();
 		
@@ -42,26 +117,43 @@ class DISCORD {
 		}
 	}
 	
+	static getMessagesFromSelectedChannel() {
+		const channelId = this.#getCurrentlySelectedChannelId();
+		return channelId ? this.#getMessages(channelId) : null;
+	}
+	
 	/**
 	 * Calls the provided function with a list of messages whenever the currently loaded messages change.
+	 * @param callback {function(server: ?DiscordGuild, channel: DiscordChannel, messages: Array<DiscordMessage>, hasMoreBefore: boolean)}
 	 */
 	static setupMessageCallback(callback) {
 		const previousMessages = new Set();
 		
-		const onMessageElementsChanged = function() {
+		const onMessageElementsChanged = force => {
-			const messages = DISCORD.getMessages();
+			const messages = this.getMessagesFromSelectedChannel();
-			const hasChanged = messages.some(message => !previousMessages.has(message.id)) || !DISCORD.hasMoreMessages();
+			if (!messages || !messages.ready || messages.loadingMore) {
+				return false;
+			}
 			
+			const channel = this.#channelStore.getChannel(messages.channelId);
+			if (!channel) {
+				return false;
+			}
+			
+			const hasChanged = force || !messages.hasMoreBefore || messages.some(message => !previousMessages.has(message.id));
 			if (!hasChanged) {
-				return;
+				return false;
 			}
 			
 			previousMessages.clear();
-			for (const message of messages) {
+			for (const message of messages._array) {
 				previousMessages.add(message.id);
 			}
 			
-			callback(messages);
+			const server = this.#guildStore.getGuild(channel.guild_id);
+			
+			callback(server, channel, messages._array, messages.hasMoreBefore);
+			return true;
 		};
 		
 		let debounceTimer;
@@ -112,216 +204,54 @@ class DISCORD {
 			observedElement = null;
 			window.clearInterval(observerTimer);
 		});
-	}
 		
-	/**
+		return () => onMessageElementsChanged(true);
-	 * Returns the message from a message element.
-	 * @returns { null | DiscordMessage } }
-	 */
-	static getMessageFromElement(ele) {
-		const props = DOM.getReactProps(ele);
-		
-		if (props && Array.isArray(props.children)) {
-			for (const child of props.children) {
-				if (!(child instanceof Object)) {
-					continue;
-				}
-				
-				const childProps = child.props;
-				if (childProps instanceof Object && "message" in childProps) {
-					return childProps.message;
-				}
-			}
-		}
-		
-		return null;
-	}
-	
-	/**
-	 * Returns an array containing currently loaded messages.
-	 */
-	static getMessages() {
-		try {
-			const messages = [];
-			
-			for (const ele of this.getMessageElements()) {
-				try {
-					const message = this.getMessageFromElement(ele);
-					
-					if (message != null) {
-						messages.push(message);
-					}
-				} catch (e) {
-					console.error("[DHT] Error extracing message data, skipping it.", e, ele, DOM.tryGetReactProps(ele));
-				}
-			}
-			
-			return messages;
-		} catch (e) {
-			console.error("[DHT] Error retrieving messages.", e);
-			return [];
-		}
-	}
-	
-	/**
-	 * Returns an object containing the selected server and channel information.
-	 * For types DM and GROUP, the server and channel ids and names are identical.
-	 * @returns { {} | null }
-	 */
-	static getSelectedChannel() {
-		try {
-			let obj = null;
-			
-			try {
-				for (const child of DOM.getReactProps(DOM.queryReactClass("chatContent")).children) {
-					if (child && child.props && child.props.channel) {
-						obj = child.props.channel;
-						break;
-					}
-				}
-			} catch (e) {
-				console.error("[DHT] Error retrieving selected channel from 'chatContent' element.", e);
-			}
-			
-			if (!obj || typeof obj.id !== "string") {
-				return null;
-			}
-			
-			const dms = DOM.queryReactClass("privateChannels");
-			
-			if (dms) {
-				let name;
-				
-				for (const ele of dms.querySelectorAll("[class*='channel_'] [class*='selected_'] [class^='name_'] *")) {
-					const node = Array.prototype.find.call(ele.childNodes, node => node.nodeType === Node.TEXT_NODE);
-					
-					if (node) {
-						name = node.nodeValue;
-						break;
-					}
-				}
-				
-				if (!name) {
-					return null;
-				}
-				
-				let type;
-				
-				// https://discord.com/developers/docs/resources/channel#channel-object-channel-types
-				switch (obj.type) {
-					case DISCORD.CHANNEL_TYPE.DM: type = "DM"; break;
-					case DISCORD.CHANNEL_TYPE.GROUP_DM: type = "GROUP"; break;
-					default: return null;
-				}
-				
-				const id = obj.id;
-				const server = { id, name, type };
-				const channel = { id, name };
-				
-				return { server, channel };
-			}
-			else if (obj.guild_id) {
-				let guild;
-				
-				for (const child of DOM.getReactProps(document.querySelector("nav header [class*='headerContent_']")).children) {
-					if (child && child.props && child.props.guild) {
-						guild = child.props.guild;
-						break;
-					}
-				}
-				
-				if (!guild || typeof guild.name !== "string" || obj.guild_id !== guild.id) {
-					return null;
-				}
-				
-				const server = {
-					"id": guild.id,
-					"name": guild.name,
-					"type": "SERVER"
-				};
-				
-				const channel = {
-					"id": obj.id,
-					"name": obj.name,
-					"extra": {
-						"nsfw": obj.nsfw
-					}
-				};
-				
-				if (obj.type === DISCORD.CHANNEL_TYPE.ANNOUNCEMENT_THREAD || obj.type === DISCORD.CHANNEL_TYPE.PUBLIC_THREAD || obj.type === DISCORD.CHANNEL_TYPE.PRIVATE_THREAD) {
-					channel["extra"]["parent"] = obj.parent_id;
-				}
-				else {
-					channel["extra"]["position"] = obj.position;
-					channel["extra"]["topic"] = obj.topic;
-				}
-				
-				return { server, channel };
-			}
-			else {
-				return null;
-			}
-		} catch (e) {
-			console.error("[DHT] Error retrieving selected channel.", e);
-			return null;
-		}
 	}
 	
 	/**
 	 * Selects the next text channel and returns true, otherwise returns false if there are no more channels.
 	 */
 	static selectNextTextChannel() {
-		const dms = DOM.queryReactClass("privateChannels");
+		const currentChannel = this.#channelStore.getChannel(this.#getCurrentlySelectedChannelId());
-		
+		if (!currentChannel) {
-		if (dms) {
-			const currentChannel = DOM.queryReactClass("selected", dms);
-			const currentChannelContainer = currentChannel && currentChannel.closest("[class*='channel_']");
-			const nextChannel = currentChannelContainer && currentChannelContainer.nextElementSibling;
-			
-			if (!nextChannel || !nextChannel.getAttribute("class").includes("channel_")) {
 			return false;
 		}
 		
-			const nextChannelLink = nextChannel.querySelector("a[href*='/@me/']");
+		if (this.CHANNEL_TYPE.isPrivate(currentChannel.type)) {
-			if (!nextChannelLink) {
+			const privateChannel = this.#channelStore.getSortedPrivateChannels();
+			const currentIndex = privateChannel.findIndex(channel => channel.id === currentChannel.id);
+			
+			if (currentIndex === -1 || currentIndex === privateChannel.length - 1) {
 				return false;
 			}
 			
-			nextChannelLink.click();
+			this.#selectPrivateChannel(privateChannel[currentIndex + 1].id);
-			nextChannelLink.scrollIntoView(true);
 			return true;
 		}
 		else {
-			const channelListEle = document.getElementById("channels");
+			const guildId = currentChannel.guild_id;
-			if (!channelListEle) {
+			
+			let isChannelOptedIn;
+			if (this.#guildSettings.isOptInEnabled(guildId)) {
+				const optedInChannels = this.#guildSettings.getOptedInChannels(guildId);
+				isChannelOptedIn = channel => optedInChannels.has(channel.id);
+			}
+			else {
+				isChannelOptedIn = _ => true;
+			}
+			
+			const guildChannelMap = this.#channelStore.getMutableGuildChannelsForGuild(guildId);
+			const guildChannels = Object.values(guildChannelMap)
+				.filter(channel => this.CHANNEL_TYPE.isNavigableGuildChannel(channel.type) && isChannelOptedIn(channel) && this.#hasPermission(this.PERMISSION.VIEW_CHANNEL, channel))
+				.sort((a, b) => a.position - b.position);
+			
+			const currentIndex = guildChannels.findIndex(channel => channel.id === currentChannel.id);
+			
+			if (currentIndex === -1 || currentIndex === guildChannels.length - 1) {
 				return false;
 			}
 			
-			function getLinkElement(channel) {
+			this.#transitionToGuildSync(guildId, {}, guildChannels[currentIndex + 1].id);
-				return channel.querySelector("a[href^='/channels/'][role='link']");
-			}
-			
-			const allTextChannels = Array.prototype.filter.call(channelListEle.querySelectorAll("[class*='containerDefault']"), ele => getLinkElement(ele) !== null);
-			let nextChannel = null;
-			
-			for (let index = 0; index < allTextChannels.length - 1; index++) {
-				if (allTextChannels[index].className.includes("selected_")) {
-					nextChannel = allTextChannels[index + 1];
-					break;
-				}
-			}
-			
-			if (nextChannel === null) {
-				return false;
-			}
-			
-			const nextChannelLink = getLinkElement(nextChannel);
-			if (!nextChannelLink) {
-				return false;
-			}
-			
-			nextChannelLink.click();
-			nextChannel.scrollIntoView(true);
 			return true;
 		}
 	}

app/Resources/Tracker/scripts/dom.js

@@ -1,6 +1,8 @@
 class DOM {
 	/**
 	 * Returns a child element by its ID. Parent defaults to the entire document.
+	 * @param {string} id
+	 * @param {HTMLElement?} [parent]
 	 * @returns {HTMLElement}
 	 */
 	static id(id, parent) {
@@ -9,6 +11,9 @@ class DOM {
 	
 	/**
 	 * Returns the first child element containing the specified obfuscated class. Parent defaults to the entire document.
+	 * @param {string} cls
+	 * @param {HTMLElement?} [parent]
+	 * @returns {HTMLElement}
 	 */
 	static queryReactClass(cls, parent) {
 		return (parent || document).querySelector(`[class*="${cls}_"]`);
@@ -55,31 +60,4 @@ class DOM {
 		const value = document.cookie.replace(new RegExp("(?:(?:^|.*;\\s*)" + name + "\\s*\\=\\s*([^;]*).*$)|^.*$"), "$1");
 		return value.length ? JSON.parse(decodeURIComponent(value)) : null;
 	}
-	
-	/**
-	 * Returns internal React state object of an element.
-	 */
-	static getReactProps(ele) {
-		const keys = Object.keys(ele || {});
-		let key = keys.find(key => key.startsWith("__reactInternalInstance"));
-		
-		if (key) {
-			// noinspection JSUnresolvedVariable
-			return ele[key].memoizedProps;
-		}
-		
-		key = keys.find(key => key.startsWith("__reactProps$"));
-		return key ? ele[key] : null;
-	}
-	
-	/**
-	 * Returns internal React state object of an element, or null if the retrieval throws.
-	 */
-	static tryGetReactProps(ele) {
-		try {
-			return this.getReactProps(ele);
-		} catch (e) {
-			return null;
-		}
-	}
 }

app/Resources/Tracker/scripts/gui.js

@@ -2,14 +2,17 @@
 const GUI = (function() {
 	let controller = null;
 	let settings = null;
+	let trackingStyles = null;
 	
 	const stateChangedEvent = () => {
 		if (settings) {
 			settings.ui.cbAutoscroll.checked = SETTINGS.autoscroll;
+			settings.ui.cbHidePreviewsWhileAutoscrolling.checked = SETTINGS.hidePreviewsWhileAutoscrolling;
 			settings.ui.optsAfterFirstMsg[SETTINGS.afterFirstMsg].checked = true;
 			settings.ui.optsAfterSavedMsg[SETTINGS.afterSavedMsg].checked = true;
 			
 			const autoscrollDisabled = !SETTINGS.autoscroll;
+			settings.ui.cbHidePreviewsWhileAutoscrolling.disabled = autoscrollDisabled;
 			Object.values(settings.ui.optsAfterFirstMsg).forEach(ele => ele.disabled = autoscrollDisabled);
 			Object.values(settings.ui.optsAfterSavedMsg).forEach(ele => ele.disabled = autoscrollDisabled);
 		}
@@ -54,6 +57,7 @@ const GUI = (function() {
 			
 			controller.ui.btnClose.addEventListener("click", () => {
 				this.hideController();
+				this.deleteTrackingStyles();
 				window.DHT_ON_UNLOAD.forEach(f => f());
 				delete window.DHT_ON_UNLOAD;
 				delete window.DHT_LOADED;
@@ -84,6 +88,7 @@ const GUI = (function() {
 			const radio = (type, id, label) => "<label><input id='dht-cfg-" + type + "-" + id + "' name='dht-" + type + "' type='radio'> " + label + "</label><br>";
 			const html = `
 <label><input id='dht-cfg-autoscroll' type='checkbox'> Autoscroll</label><br>
+<label><input id='dht-cfg-hide-previews-while-autoscrolling' type='checkbox'> Hide previews to improve browser performance</label><br>
 <br>
 <label>After reaching the first message in channel...</label><br>
 ${radio("afm", "nothing", "Continue Tracking")}
@@ -93,8 +98,7 @@ ${radio("afm", "switch", "Switch to Next Channel")}
 <label>After reaching a previously saved message...</label><br>
 ${radio("asm", "nothing", "Continue Tracking")}
 ${radio("asm", "pause", "Pause Tracking")}
-${radio("asm", "switch", "Switch to Next Channel")}
+${radio("asm", "switch", "Switch to Next Channel")}`;
-<p id='dht-cfg-note'>It is recommended to disable link and image previews to avoid putting unnecessary strain on your browser.</p>`;
 			
 			settings = {
 				styles: DOM.createStyle(`/*[CSS-SETTINGS]*/`),
@@ -107,9 +111,10 @@ ${radio("asm", "switch", "Switch to Next Channel")}
 			});
 			
 			settings.ui = {
-				cbAutoscroll: DOM.id("dht-cfg-autoscroll"),
+				/** @type {HTMLInputElement} */ cbAutoscroll: DOM.id("dht-cfg-autoscroll"),
-				optsAfterFirstMsg: {},
+				/** @type {HTMLInputElement} */ cbHidePreviewsWhileAutoscrolling: DOM.id("dht-cfg-hide-previews-while-autoscrolling"),
-				optsAfterSavedMsg: {}
+				/** @type {Object.<number, HTMLInputElement>} */ optsAfterFirstMsg: {},
+				/** @type {Object.<number, HTMLInputElement>} */ optsAfterSavedMsg: {}
 			};
 			
 			settings.ui.optsAfterFirstMsg[CONSTANTS.AUTOSCROLL_ACTION_NOTHING] = DOM.id("dht-cfg-afm-nothing");
@@ -124,6 +129,10 @@ ${radio("asm", "switch", "Switch to Next Channel")}
 				SETTINGS.autoscroll = settings.ui.cbAutoscroll.checked;
 			});
 			
+			settings.ui.cbHidePreviewsWhileAutoscrolling.addEventListener("change", () => {
+				SETTINGS.hidePreviewsWhileAutoscrolling = settings.ui.cbHidePreviewsWhileAutoscrolling.checked;
+			});
+			
 			Object.keys(settings.ui.optsAfterFirstMsg).forEach(key => {
 				settings.ui.optsAfterFirstMsg[key].addEventListener("click", () => {
 					SETTINGS.afterFirstMsg = key;
@@ -152,6 +161,29 @@ ${radio("asm", "switch", "Switch to Next Channel")}
 			if (controller) {
 				controller.ui.textStatus.innerText = state;
 			}
+		},
+		
+		createTrackingStyles() {
+			if (trackingStyles) {
+				return;
+			}
+			
+			let style = "";
+			
+			if (SETTINGS.autoscroll && SETTINGS.hidePreviewsWhileAutoscrolling) {
+				style += `div[id^="message-accessories-"] { display: none; }`;
+			}
+			
+			if (style.length > 0) {
+				trackingStyles = DOM.createStyle(style);
+			}
+		},
+		
+		deleteTrackingStyles() {
+			if (trackingStyles) {
+				DOM.removeElement(trackingStyles);
+				trackingStyles = null;
+			}
 		}
 	};
 })();

app/Resources/Tracker/scripts/settings.js

@@ -35,17 +35,28 @@ const SETTINGS = (function() {
 		obj[name] = value;
 	};
 	
-	let loaded = DOM.loadFromCookie("DHT_SETTINGS");
+	const defaults = {
-	
-	if (!loaded) {
-		loaded = {
 		"_autoscroll": true,
+		"_hidePreviewsWhileAutoscrolling": true,
 		"_afterFirstMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE,
-			"_afterSavedMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE
+		"_afterSavedMsg": CONSTANTS.AUTOSCROLL_ACTION_PAUSE,
 	};
 	
+	let loaded = DOM.loadFromCookie("DHT_SETTINGS");
+	let hasChanged = false;
+	
+	if (!loaded) {
+		loaded = defaults;
 		IS_FIRST_RUN = true;
 	}
+	else {
+		for (const property in defaults) {
+			if (!(property in loaded)) {
+				loaded[property] = defaults[property];
+				hasChanged = true;
+			}
+		}
+	}
 	
 	const root = {
 		onSettingsChanged(callback) {
@@ -54,10 +65,11 @@ const SETTINGS = (function() {
 	};
 	
 	defineTriggeringProperty(root, "autoscroll", loaded._autoscroll);
+	defineTriggeringProperty(root, "hidePreviewsWhileAutoscrolling", loaded._hidePreviewsWhileAutoscrolling);
 	defineTriggeringProperty(root, "afterFirstMsg", loaded._afterFirstMsg);
 	defineTriggeringProperty(root, "afterSavedMsg", loaded._afterSavedMsg);
 	
-	if (IS_FIRST_RUN) {
+	if (IS_FIRST_RUN || hasChanged) {
 		saveSettings();
 	}
 	

app/Resources/Tracker/scripts/state.js

@@ -58,65 +58,39 @@ const STATE = (function() {
 		}
 	};
 	
+	/**
+	 * @param {DiscordChannel} channel
+	 */
+	const getPrivateChannelName = function(channel) {
+		if (channel.name === "") {
+			return channel.rawRecipients.map(user => user.username).join(", ");
+		}
+		else {
+			return channel.name;
+		}
+	};
+	
+	/**
+	 * @param {Number} type
+	 */
+	const getChannelTypeName = function(type) {
+		if (type === DISCORD.CHANNEL_TYPE.DM) {
+			return "DM";
+		}
+		else if (type === DISCORD.CHANNEL_TYPE.GROUP_DM) {
+			return "GROUP";
+		}
+		else {
+			return "SERVER";
+		}
+	};
+	
 	const trackingStateChangedListeners = [];
 	let isTracking = false;
 	
 	const addedChannels = new Set();
 	const addedUsers = new Set();
 	
-	/**
-	 * @name DiscordUser
-	 * @property {String} id
-	 * @property {String} username
-	 * @property {String} discriminator
-	 * @property {String} [globalName]
-	 * @property {String} [avatar]
-	 * @property {Boolean} [bot]
-	 */
-	
-	/**
-	 * @name DiscordMessage
-	 * @property {String} id
-	 * @property {String} channel_id
-	 * @property {DiscordUser} author
-	 * @property {String} content
-	 * @property {Date} timestamp
-	 * @property {Date|null} editedTimestamp
-	 * @property {DiscordAttachment[]} attachments
-	 * @property {Object[]} embeds
-	 * @property {DiscordMessageReaction[]} [reactions]
-	 * @property {DiscordMessageReference} [messageReference]
-	 * @property {Number} type
-	 * @property {String} state
-	 */
-	
-	/**
-	 * @name DiscordAttachment
-	 * @property {String} id
-	 * @property {String} filename
-	 * @property {String} [content_type]
-	 * @property {String} size
-	 * @property {String} url
-	 */
-	
-	/**
-	 * @name DiscordMessageReaction
-	 * @property {DiscordEmoji} emoji
-	 * @property {Number} count
-	 */
-	
-	/**
-	 * @name DiscordMessageReference
-	 * @property {String} [message_id]
-	 */
-	
-	/**
-	 * @name DiscordEmoji
-	 * @property {String|null} id
-	 * @property {String|null} name
-	 * @property {Boolean} animated
-	 */
-	
 	return {
 		setup(port, token) {
 			serverPort = port;
@@ -147,32 +121,59 @@ const STATE = (function() {
 			}
 		},
 		
+		/**
+		 * @param {?DiscordGuild} serverInfo
+		 * @param {DiscordChannel} channelInfo
+		 */
 		async addDiscordChannel(serverInfo, channelInfo) {
 			if (addedChannels.has(channelInfo.id)) {
 				return;
 			}
 			
 			const server = {
-				id: serverInfo.id,
+				type: getChannelTypeName(channelInfo.type)
-				name: serverInfo.name,
-				type: serverInfo.type
 			};
 			
 			const channel = {
 				id: channelInfo.id,
-				name: channelInfo.name
+				extra: {}
 			};
 			
-			if ("extra" in channelInfo) {
+			if (DISCORD.CHANNEL_TYPE.isPrivate(channelInfo.type)) {
-				const extra = channelInfo.extra;
+				server.id = channelInfo.id;
+				server.name = channel.name = getPrivateChannelName(channelInfo);
 				
-				if ("parent" in extra) {
+				if (channelInfo.icon) {
-					channel.parent = extra.parent;
+					server.icon = channelInfo.icon;
+				}
+			}
+			else if (serverInfo) {
+				server.id = serverInfo.id;
+				server.name = serverInfo.name;
+				channel.name = channelInfo.name;
+				
+				if (serverInfo.icon) {
+					server.icon = serverInfo.icon;
+				}
+			}
+			else {
+				return;
 			}
 			
-				channel.position = extra.position;
+			if ("nsfw" in channelInfo) {
-				channel.topic = extra.topic;
+				channel.extra.nsfw = channelInfo.nsfw;
-				channel.nsfw = extra.nsfw;
+			}
+			
+			if ("topic" in channelInfo) {
+				channel.extra.topic = channelInfo.topic;
+			}
+			
+			if ("position" in channelInfo) {
+				channel.extra.position = channelInfo.position;
+			}
+			
+			if (channelInfo.type === DISCORD.CHANNEL_TYPE.ANNOUNCEMENT_THREAD || channelInfo.type === DISCORD.CHANNEL_TYPE.PUBLIC_THREAD || channelInfo.type === DISCORD.CHANNEL_TYPE.PRIVATE_THREAD) {
+				channel.extra.parent = channelInfo.parent_id;
 			}
 			
 			await post("/track-channel", { server, channel });
@@ -293,7 +294,7 @@ const STATE = (function() {
 				}
 				
 				if (msg.reactions.length > 0) {
-					obj.reactions = msg.reactions.map(reaction => {
+					obj.reactions = msg.reactions.filter(reaction => reaction.count > 0).map(reaction => {
 						const emoji = reaction.emoji;
 						
 						const mapped = {

app/Resources/Tracker/scripts/types.js

@@ -0,0 +1,84 @@
+/**
+ * @name DiscordGuild
+ * @property {String} id
+ * @property {String} name
+ * @property {String|null|undefined} [icon]
+ */
+
+/**
+ * @name DiscordChannel
+ * @property {String} id
+ * @property {String} name
+ * @property {Number} type
+ * @property {String} [guild_id]
+ * @property {String} [parent_id]
+ * @property {Number} [position]
+ * @property {String} [topic]
+ * @property {Boolean} [nsfw]
+ * @property {String|null|undefined} [icon]
+ * @property {DiscordUser[]} [rawRecipients]
+ */
+
+/**
+ * @name DiscordUser
+ * @property {String} id
+ * @property {String} username
+ * @property {String} discriminator
+ * @property {String} [globalName]
+ * @property {String} [avatar]
+ * @property {Boolean} [bot]
+ */
+
+/**
+ * @name DiscordMessage
+ * @property {String} id
+ * @property {String} channel_id
+ * @property {DiscordUser} author
+ * @property {String} content
+ * @property {Date} timestamp
+ * @property {Date|null} editedTimestamp
+ * @property {DiscordAttachment[]} attachments
+ * @property {Object[]} embeds
+ * @property {DiscordMessageReaction[]} [reactions]
+ * @property {DiscordMessageReference} [messageReference]
+ * @property {Number} type
+ * @property {String} state
+ */
+
+/**
+ * @name DiscordAttachment
+ * @property {String} id
+ * @property {String} filename
+ * @property {String} [content_type]
+ * @property {String} size
+ * @property {String} url
+ */
+
+/**
+ * @name DiscordMessageReaction
+ * @property {DiscordEmoji} emoji
+ * @property {Number} count
+ */
+
+/**
+ * @name DiscordMessageReference
+ * @property {String} [message_id]
+ */
+
+/**
+ * @name DiscordEmoji
+ * @property {String|null} id
+ * @property {String|null} name
+ * @property {Boolean} animated
+ */
+
+/**
+ * @name MessageData
+ * @type {Object}
+ * @property {String} channelId
+ * @property {Boolean} ready
+ * @property {Boolean} loadingMore
+ * @property {Boolean} hasMoreAfter
+ * @property {Boolean} hasMoreBefore
+ * @property {Array<DiscordMessage>} _array
+ */

app/Resources/Tracker/scripts/webpack.js

@@ -0,0 +1,100 @@
+/**
+ * Parts copied from Better Discord, licensed under Apache License 2.0.
+ *
+ * https://github.com/BetterDiscord/BetterDiscord/blob/2752daf64f98625fc67c569361bd56021307d058/renderer/src/modules/webpackmodules.js
+ * https://github.com/BetterDiscord/BetterDiscord/blob/2752daf64f98625fc67c569361bd56021307d058/LICENSE
+ */
+class WEBPACK {
+	static get require() {
+		if (this._require) {
+			return this._require;
+		}
+		
+		/**
+		 * @type {Object}
+		 * @property {Object} m
+		 * @property {Object} c
+		 */
+		let hookedRequire;
+		
+		const id = Symbol("dht-webpackmodules-" + new Date().getTime());
+		if (typeof (window["webpackChunkdiscord_app"]) !== "undefined") {
+			window["webpackChunkdiscord_app"].push([ [ id ], {}, internalRequire => {
+				if ("b" in internalRequire) {
+					hookedRequire = internalRequire;
+				}
+			}]);
+		}
+		
+		return this._require = hookedRequire;
+	}
+	
+	static getAllModules() {
+		return this.require.c;
+	}
+	
+	static filterByProps(...props) {
+		return module => props.every(prop => prop in module);
+	}
+	
+	static filterByPropsWithPredicate(predicate, ...props) {
+		return module => props.every(prop => prop in module && predicate(module[prop]));
+	}
+	
+	static findModules(filter) {
+		const defaultExport = true;
+		const moduleFilter = module => (typeof module === "object" || typeof module === "function") && filter(module);
+		
+		const results = [];
+		
+		for (const module of Object.values(this.getAllModules())) {
+			/**
+			 * @type {Object}
+			 * @property [Z]
+			 * @property [ZP]
+			 * @property [__esModule]
+			 * @property [default]
+			 */
+			const exports = module.exports;
+			if (!exports || exports === window || exports === document.documentElement || exports[Symbol.toStringTag] === "DOMTokenList") {
+				continue;
+			}
+			
+			let foundModule = null;
+			if (exports.Z && moduleFilter(exports.Z)) {
+				foundModule = defaultExport ? exports.Z : exports;
+			}
+			if (exports.ZP && moduleFilter(exports.ZP)) {
+				foundModule = defaultExport ? exports.ZP : exports;
+			}
+			if (exports.__esModule && exports.default && moduleFilter(exports.default)) {
+				foundModule = defaultExport ? exports.default : exports;
+			}
+			if (moduleFilter(exports)) {
+				foundModule = exports;
+			}
+			
+			if (foundModule) {
+				results.push(foundModule);
+			}
+		}
+		
+		return results;
+	}
+	
+	static findModule(name, filter) {
+		const modules = this.findModules(filter);
+		if (modules.length === 1) {
+			return modules[0];
+		}
+		
+		console.error("[DHT] Cannot find module " + name + ", results found:", modules.length, modules);
+		return null;
+	}
+	
+	static findFunction(name, additionalRequiredProps) {
+		const searchedProps = additionalRequiredProps ? [ name, ...additionalRequiredProps ] : [ name ];
+		const matchingModule = this.findModule("containing function " + name, this.filterByPropsWithPredicate(prop => typeof (prop) === "function", ...searchedProps));
+		return matchingModule == null ? null : matchingModule[name].bind(matchingModule);
+	}
+}

app/Resources/Tracker/styles/settings.css

@@ -18,11 +18,13 @@
   height: 262px;
   margin-left: -400px;
   margin-top: -131px;
+  line-height: 120%;
   padding: 8px;
   background-color: #fff;
   z-index: 1000002;
 }
 
-#dht-cfg-note {
+#dht-cfg label {
-  margin-top: 22px;
+  display: inline-block;
+  margin: 1px 0;
 }

app/Resources/Viewer/scripts/discord.mjs

@@ -107,7 +107,7 @@ export default (function() {
 	const isImageUrl = function(url) {
 		const dot = url.pathname.lastIndexOf(".");
 		const ext = dot === -1 ? "" : url.pathname.substring(dot).toLowerCase();
-		return ext === ".png" || ext === ".gif" || ext === ".jpg" || ext === ".jpeg";
+		return ext === ".png" || ext === ".gif" || ext === ".jpg" || ext === ".jpeg" || ext === ".webp" || ext === ".avif";
 	};
 	
 	return {

app/Resources/Viewer/styles/messages.css

@@ -1,7 +1,7 @@
 #messages {
   flex: 1 1 0;
   overflow-y: auto;
-  background-color: #36393E;
+  background-color: #36393e;
 }
 
 #messages > div {
@@ -38,7 +38,7 @@
 }
 
 #messages .username {
-  color: #FFF;
+  color: #fff;
   font-size: 15px;
   font-weight: 600;
   margin-right: 3px;
@@ -75,12 +75,12 @@
 }
 
 .message .link, .reply-message .link {
-  color: #7289DA;
+  color: #7289da;
   background-color: rgba(115, 139, 215, 0.1);
 }
 
 .message a, .reply-message a {
-  color: #0096CF;
+  color: #0096cf;
   text-decoration: none;
 }
 
@@ -131,7 +131,7 @@
 }
 
 .message code {
-  background-color: #2E3136;
+  background-color: #2e3136;
   border-radius: 5px;
   font-family: Menlo, Consolas, Monaco, monospace;
   font-size: 14px;
@@ -144,7 +144,7 @@
 
 .message code.block {
   display: block;
-  border: 2px solid #282B30;
+  border: 2px solid #282b30;
   margin-top: 6px;
   padding: 7px;
 }
@@ -198,7 +198,7 @@
 }
 
 .reply-username {
-  color: #FFF;
+  color: #fff;
   font-size: 12px;
   font-weight: 600;
   letter-spacing: 0;
@@ -218,7 +218,7 @@
 }
 
 .reply-contents code {
-  background-color: #2E3136;
+  background-color: #2e3136;
   font-family: Menlo, Consolas, Monaco, monospace;
   padding: 1px 2px;
 }

app/Server/Data/DownloadStatus.cs

@@ -10,5 +10,5 @@ public enum DownloadStatus {
 	GenericError = 1,
 	Downloading = 2,
 	LastCustomCode = 99,
-	Success = HttpStatusCode.OK
+	Success = HttpStatusCode.OK,
 }

app/Server/Data/EmojiFlags.cs

@@ -5,5 +5,5 @@ namespace DHT.Server.Data;
 [Flags]
 public enum EmojiFlags : ushort {
 	None = 0,
-	Animated = 0b1
+	Animated = 0b1,
 }

app/Server/Data/FileUrl.cs

@@ -0,0 +1,9 @@
+namespace DHT.Server.Data;
+
+public readonly record struct FileUrl(string NormalizedUrl, string DownloadUrl, string? Type) {
+	public FileUrl(string url, string? type) : this(url, url, type) {}
+	
+	public Download ToPendingDownload() {
+		return new Download(NormalizedUrl, DownloadUrl, DownloadStatus.Pending, Type, size: null);
+	}
+}

app/Server/Data/Filters/FilterRemovalMode.cs

@@ -2,5 +2,5 @@ namespace DHT.Server.Data.Filters;
 
 public enum FilterRemovalMode {
 	KeepMatching,
-	RemoveMatching
+	RemoveMatching,
 }

app/Server/Data/Server.cs

@@ -1,7 +1,12 @@
+using DHT.Server.Download;
+
 namespace DHT.Server.Data;
 
 public readonly struct Server {
 	public ulong Id { get; init; }
 	public string Name { get; init; }
 	public ServerType? Type { get; init; }
+	public string? IconHash { get; init; }
+	
+	internal FileUrl? IconUrl => Type == null || IconHash == null ? null : DownloadLinkExtractor.ServerIcon(Type.Value, Id, IconHash);
 }

app/Server/Data/ServerType.cs

@@ -3,7 +3,7 @@ namespace DHT.Server.Data;
 public enum ServerType {
 	Server,
 	Group,
-	DirectMessage
+	DirectMessage,
 }
 
 public static class ServerTypes {
@@ -12,7 +12,7 @@ public static class ServerTypes {
 			"SERVER" => ServerType.Server,
 			"GROUP"  => ServerType.Group,
 			"DM"     => ServerType.DirectMessage,
-			_        => null
+			_        => null,
 		};
 	}
 	
@@ -21,7 +21,7 @@ public static class ServerTypes {
 			ServerType.Server        => "SERVER",
 			ServerType.Group         => "GROUP",
 			ServerType.DirectMessage => "DM",
-			_                        => "UNKNOWN"
+			_                        => "UNKNOWN",
 		};
 	}
 	
@@ -30,7 +30,7 @@ public static class ServerTypes {
 			ServerType.Server        => "Server",
 			ServerType.Group         => "Group",
 			ServerType.DirectMessage => "DM",
-			_                        => "Unknown"
+			_                        => "Unknown",
 		};
 	}
 	
@@ -39,7 +39,7 @@ public static class ServerTypes {
 			ServerType.Server        => "server",
 			ServerType.Group         => "group",
 			ServerType.DirectMessage => "user",
-			_                        => "unknown"
+			_                        => "unknown",
 		};
 	}
 }

app/Server/Data/Settings/SettingsKey.cs

@@ -3,6 +3,7 @@ using System.Diagnostics.CodeAnalysis;
 namespace DHT.Server.Data.Settings;
 
 public static class SettingsKey {
+	public static Bool SeparateFileForDownloads { get; } = new ("separate_file_for_downloads");
 	public static Bool DownloadsAutoStart { get; } = new ("downloads_auto_start");
 	public static Bool DownloadsLimitSize { get; } = new ("downloads_limit_size");
 	public static UnsignedLong DownloadsMaximumSize { get; } = new ("downloads_maximum_size");

app/Server/Data/User.cs

@@ -1,9 +1,13 @@
+using DHT.Server.Download;
+
 namespace DHT.Server.Data;
 
 public readonly struct User {
 	public ulong Id { get; init; }
 	public string Name { get; init; }
 	public string? DisplayName { get; init; }
-	public string? AvatarUrl { get; init; }
+	public string? AvatarHash { get; init; }
 	public string? Discriminator { get; init; }
+	
+	internal FileUrl? AvatarUrl => AvatarHash == null ? null : DownloadLinkExtractor.UserAvatar(Id, AvatarHash);
 }

app/Server/Database/DatabaseExtensions.cs

@@ -1,34 +0,0 @@
-using System.Collections.Generic;
-using System.Linq;
-using System.Threading.Tasks;
-using DHT.Server.Data;
-
-namespace DHT.Server.Database;
-
-public static class DatabaseExtensions {
-	public static async Task AddFrom(this IDatabaseFile target, IDatabaseFile source) {
-		await target.Users.Add(await source.Users.Get().ToListAsync());
-		await target.Servers.Add(await source.Servers.Get().ToListAsync());
-		await target.Channels.Add(await source.Channels.Get().ToListAsync());
-
-		const int MessageBatchSize = 100;
-		List<Message> batchedMessages = new (MessageBatchSize);
-		
-		await foreach (var message in source.Messages.Get()) {
-			batchedMessages.Add(message);
-
-			if (batchedMessages.Count >= MessageBatchSize) {
-				await target.Messages.Add(batchedMessages);
-				batchedMessages.Clear();
-			}
-		}
-		
-		await target.Messages.Add(batchedMessages);
-
-		await foreach (var download in source.Downloads.Get()) {
-			if (download.Status != DownloadStatus.Success || !await source.Downloads.GetDownloadData(download.NormalizedUrl, stream => target.Downloads.AddDownload(download, stream))) {
-				await target.Downloads.AddDownload(download, stream: null);
-			}
-		}
-	}
-}

app/Server/Database/DummyDatabaseFile.cs

@@ -19,6 +19,10 @@ sealed class DummyDatabaseFile : IDatabaseFile {
 	
 	private DummyDatabaseFile() {}
 	
+	public Task<string?> GetVersion() {
+		return Task.FromResult<string?>(null);
+	}
+	
 	public Task Vacuum() {
 		return Task.CompletedTask;
 	}

app/Server/Database/Export/SnowflakeJsonSerializer.cs

@@ -1,16 +1,20 @@
 using System;
+using System.Buffers.Text;
+using System.Diagnostics;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
 namespace DHT.Server.Database.Export;
 
 sealed class SnowflakeJsonSerializer : JsonConverter<Snowflake> {
+	private const int MaxUlongStringLength = 20;
+	
 	public override Snowflake Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
 		return new Snowflake(ulong.Parse(reader.GetString()!));
 	}
 	
 	public override void Write(Utf8JsonWriter writer, Snowflake value, JsonSerializerOptions options) {
-		writer.WriteStringValue(value.Id.ToString());
+		writer.WriteStringValue(Format(value, stackalloc byte[MaxUlongStringLength]));
 	}
 	
 	public override Snowflake ReadAsPropertyName(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
@@ -18,6 +22,14 @@ sealed class SnowflakeJsonSerializer : JsonConverter<Snowflake> {
 	}
 	
 	public override void WriteAsPropertyName(Utf8JsonWriter writer, Snowflake value, JsonSerializerOptions options) {
-		writer.WritePropertyName(value.Id.ToString());
+		writer.WritePropertyName(Format(value, stackalloc byte[MaxUlongStringLength]));
+	}
+	
+	private static ReadOnlySpan<byte> Format(Snowflake value, Span<byte> destination) {
+		if (!Utf8Formatter.TryFormat(value.Id, destination, out int bytesWritten)) {
+			Debug.Fail("Failed to format Snowflake value.");
+		}
+		
+		return destination[..bytesWritten];
 	}
 }

app/Server/Database/Export/ViewerJson.cs

@@ -23,6 +23,9 @@ static class ViewerJson {
 	public sealed class JsonServer {
 		public required string Name { get; init; }
 		public required string Type { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? IconUrl { get; init; }
 	}
 	
 	public sealed class JsonChannel {
@@ -30,7 +33,7 @@ static class ViewerJson {
 		public required string Name { get; init; }
 		
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
-		public string? Parent { get; init; }
+		public Snowflake? Parent { get; init; }
 		
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
 		public int? Position { get; init; }
@@ -55,7 +58,7 @@ static class ViewerJson {
 		public long? Te { get; init; }
 		
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
-		public string? R { get; init; }
+		public Snowflake? R { get; init; }
 		
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
 		public JsonMessageAttachment[]? A { get; init; }
@@ -80,7 +83,7 @@ static class ViewerJson {
 	
 	public sealed class JsonMessageReaction {
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
-		public string? Id { get; init; }
+		public Snowflake? Id { get; init; }
 		
 		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
 		public string? N { get; init; }

app/Server/Database/Export/ViewerJsonExport.cs

@@ -2,13 +2,15 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
-using System.Runtime.CompilerServices;
 using System.Text.Json;
 using System.Threading;
+using System.Threading.Channels;
 using System.Threading.Tasks;
 using DHT.Server.Data;
 using DHT.Server.Data.Filters;
 using DHT.Utils.Logging;
+using Channel = System.Threading.Channels.Channel;
+using DiscordChannel = DHT.Server.Data.Channel;
 
 namespace DHT.Server.Database.Export;
 
@@ -16,28 +18,28 @@ static class ViewerJsonExport {
 	private static readonly Log Log = Log.ForType(typeof(ViewerJsonExport));
 	
 	public static async Task GetMetadata(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
-		var perf = Log.Start();
+		Perf perf = Log.Start();
 		
-		var includedChannels = new List<Channel>();
+		var includedChannels = new List<DiscordChannel>();
 		var includedServerIds = new HashSet<ulong>();
 		
-		var channelIdFilter = filter?.ChannelIds;
+		HashSet<ulong>? channelIdFilter = filter?.ChannelIds;
 		
-		await foreach (var channel in db.Channels.Get(cancellationToken)) {
+		await foreach (DiscordChannel channel in db.Channels.Get(cancellationToken)) {
 			if (channelIdFilter == null || channelIdFilter.Contains(channel.Id)) {
 				includedChannels.Add(channel);
 				includedServerIds.Add(channel.Server);
 			}
 		}
 		
-		var users = await GenerateUserList(db, cancellationToken);
+		Dictionary<Snowflake, ViewerJson.JsonUser> users = await GenerateUserList(db, cancellationToken);
-		var servers = await GenerateServerList(db, includedServerIds, cancellationToken);
+		Dictionary<Snowflake, ViewerJson.JsonServer> servers = await GenerateServerList(db, includedServerIds, cancellationToken);
-		var channels = GenerateChannelList(includedChannels);
+		Dictionary<Snowflake, ViewerJson.JsonChannel> channels = GenerateChannelList(includedChannels);
 		
 		var meta = new ViewerJson.JsonMeta {
 			Users = users,
 			Servers = servers,
-			Channels = channels
+			Channels = channels,
 		};
 		
 		perf.Step("Collect database data");
@@ -49,15 +51,34 @@ static class ViewerJsonExport {
 	}
 	
 	public static async Task GetMessages(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
-		var perf = Log.Start();
+		Perf perf = Log.Start();
 		
 		ReadOnlyMemory<byte> newLine = "\n"u8.ToArray();
 		
-		await foreach(var message in GenerateMessageList(db, filter, cancellationToken)) {
+		Channel<Message> channel = Channel.CreateBounded<Message>(new BoundedChannelOptions(32) {
-			await JsonSerializer.SerializeAsync(stream, message, ViewerJsonMessageContext.Default.JsonMessage, cancellationToken);
+			SingleWriter = true,
+			SingleReader = true,
+			AllowSynchronousContinuations = true,
+			FullMode = BoundedChannelFullMode.Wait,
+		});
+		
+		Task writerTask = Task.Run(async () => {
+			try {
+				await foreach (Message message in db.Messages.Get(filter, cancellationToken)) {
+					await channel.Writer.WriteAsync(message, cancellationToken);
+				}
+			} finally {
+				channel.Writer.Complete();
+			}
+		}, cancellationToken);
+		
+		await foreach (Message message in channel.Reader.ReadAllAsync(cancellationToken)) {
+			await JsonSerializer.SerializeAsync(stream, ToJsonMessage(message), ViewerJsonMessageContext.Default.JsonMessage, cancellationToken);
 			await stream.WriteAsync(newLine, cancellationToken);
 		}
 		
+		await writerTask;
+		
 		perf.Step("Generate and serialize messages to JSON");
 		perf.End();
 	}
@@ -65,11 +86,11 @@ static class ViewerJsonExport {
 	private static async Task<Dictionary<Snowflake, ViewerJson.JsonUser>> GenerateUserList(IDatabaseFile db, CancellationToken cancellationToken) {
 		var users = new Dictionary<Snowflake, ViewerJson.JsonUser>();
 		
-		await foreach (var user in db.Users.Get(cancellationToken)) {
+		await foreach (User user in db.Users.Get(cancellationToken)) {
 			users[user.Id] = new ViewerJson.JsonUser {
 				Name = user.Name,
 				DisplayName = user.DisplayName,
-				Avatar = user.AvatarUrl,
+				Avatar = user.AvatarHash,
 			};
 		}
 		
@@ -79,52 +100,52 @@ static class ViewerJsonExport {
 	private static async Task<Dictionary<Snowflake, ViewerJson.JsonServer>> GenerateServerList(IDatabaseFile db, HashSet<ulong> serverIds, CancellationToken cancellationToken) {
 		var servers = new Dictionary<Snowflake, ViewerJson.JsonServer>();
 		
-		await foreach (var server in db.Servers.Get(cancellationToken)) {
+		await foreach (Data.Server server in db.Servers.Get(cancellationToken)) {
 			if (!serverIds.Contains(server.Id)) {
 				continue;
 			}
 			
 			servers[server.Id] = new ViewerJson.JsonServer {
 				Name = server.Name,
-				Type = ServerTypes.ToJsonViewerString(server.Type)
+				Type = ServerTypes.ToJsonViewerString(server.Type),
+				IconUrl = server.IconUrl?.DownloadUrl,
 			};
 		}
 		
 		return servers;
 	}
 	
-	private static Dictionary<Snowflake, ViewerJson.JsonChannel> GenerateChannelList(List<Channel> includedChannels) {
+	private static Dictionary<Snowflake, ViewerJson.JsonChannel> GenerateChannelList(List<DiscordChannel> includedChannels) {
 		var channels = new Dictionary<Snowflake, ViewerJson.JsonChannel>();
 		
-		foreach (var channel in includedChannels) {
+		foreach (DiscordChannel channel in includedChannels) {
 			channels[channel.Id] = new ViewerJson.JsonChannel {
 				Server = channel.Server,
 				Name = channel.Name,
-				Parent = channel.ParentId?.ToString(),
+				Parent = channel.ParentId,
 				Position = channel.Position,
 				Topic = channel.Topic,
-				Nsfw = channel.Nsfw
+				Nsfw = channel.Nsfw,
 			};
 		}
 		
 		return channels;
 	}
 	
-	private static async IAsyncEnumerable<ViewerJson.JsonMessage> GenerateMessageList(IDatabaseFile db, MessageFilter? filter, [EnumeratorCancellation] CancellationToken cancellationToken) {
+	private static ViewerJson.JsonMessage ToJsonMessage(Message message) {
-		await foreach (var message in db.Messages.Get(filter, cancellationToken)) {
+		return new ViewerJson.JsonMessage {
-			yield return new ViewerJson.JsonMessage {
 			Id = message.Id,
 			C = message.Channel,
 			U = message.Sender,
 			T = message.Timestamp,
 			M = string.IsNullOrEmpty(message.Text) ? null : message.Text,
 			Te = message.EditTimestamp,
-				R = message.RepliedToId?.ToString(),
+			R = message.RepliedToId,
 			
 			A = message.Attachments.IsEmpty ? null : message.Attachments.Select(static attachment => {
 				var a = new ViewerJson.JsonMessageAttachment {
 					Url = attachment.DownloadUrl,
-						Name = Uri.TryCreate(attachment.NormalizedUrl, UriKind.Absolute, out var uri) ? Path.GetFileName(uri.LocalPath) : attachment.NormalizedUrl
+					Name = Uri.TryCreate(attachment.NormalizedUrl, UriKind.Absolute, out Uri? uri) ? Path.GetFileName(uri.LocalPath) : attachment.NormalizedUrl,
 				};
 				
 				if (attachment is { Width: not null, Height: not null }) {
@@ -138,12 +159,11 @@ static class ViewerJsonExport {
 			E = message.Embeds.IsEmpty ? null : message.Embeds.Select(static embed => embed.Json).ToArray(),
 			
 			Re = message.Reactions.IsEmpty ? null : message.Reactions.Select(static reaction => new ViewerJson.JsonMessageReaction {
-					Id = reaction.EmojiId?.ToString(),
+				Id = reaction.EmojiId,
 				N = reaction.EmojiName,
 				A = reaction.EmojiFlags.HasFlag(EmojiFlags.Animated),
-					C = reaction.Count
+				C = reaction.Count,
-				}).ToArray()
+			}).ToArray(),
 		};
 	}
 }
-}

app/Server/Database/IDatabaseFile.cs

@@ -14,5 +14,6 @@ public interface IDatabaseFile : IAsyncDisposable {
 	IMessageRepository Messages { get; }
 	IDownloadRepository Downloads { get; }
 	
+	Task<string?> GetVersion();
 	Task Vacuum();
 }

app/Server/Database/Import/DatabaseMerging.cs

@@ -0,0 +1,77 @@
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using DHT.Server.Data;
+
+namespace DHT.Server.Database.Import;
+
+public static class DatabaseMerging {
+	public static async Task Merge(this IDatabaseFile target, IDatabaseFile source, IProgressCallback callback) {
+		// Import downloads first, otherwise automatic downloads would try to re-download files from other imported data.
+		await MergeDownloads(target, source, callback);
+		
+		callback.OnImportingMetadata();
+		await target.Users.Add(await source.Users.Get().ToListAsync());
+		await target.Servers.Add(await source.Servers.Get().ToListAsync());
+		await target.Channels.Add(await source.Channels.Get().ToListAsync());
+		
+		await MergeMessages(target, source, callback);
+	}
+	
+	private static async Task MergeDownloads(IDatabaseFile target, IDatabaseFile source, IProgressCallback callback) {
+		const int ReportBatchSize = 100;
+		
+		long totalDownloads = await source.Downloads.Count();
+		long importedDownloads = 0;
+		
+		callback.OnDownloadsImported(importedDownloads, totalDownloads);
+		
+		await foreach (Data.Download download in source.Downloads.Get()) {
+			if (download.Status != DownloadStatus.Success || !await source.Downloads.GetDownloadData(download.NormalizedUrl, stream => target.Downloads.AddDownload(download, stream))) {
+				await target.Downloads.AddDownload(download, stream: null);
+			}
+			
+			if (++importedDownloads % ReportBatchSize == 0) {
+				callback.OnDownloadsImported(importedDownloads, totalDownloads);
+			}
+		}
+		
+		callback.OnDownloadsImported(totalDownloads, totalDownloads);
+	}
+	
+	private static async Task MergeMessages(IDatabaseFile target, IDatabaseFile source, IProgressCallback callback) {
+		const int MessageBatchSize = 100;
+		const int ReportEveryBatches = 10;
+		List<Message> batchedMessages = new (MessageBatchSize);
+		
+		long totalMessages = await source.Messages.Count();
+		long importedMessages = 0;
+		
+		callback.OnMessagesImported(importedMessages, totalMessages);
+		
+		await foreach (Message message in source.Messages.Get()) {
+			batchedMessages.Add(message);
+			
+			if (batchedMessages.Count >= MessageBatchSize) {
+				await target.Messages.Add(batchedMessages);
+				
+				importedMessages += batchedMessages.Count;
+				
+				if (importedMessages % (MessageBatchSize * ReportEveryBatches) == 0) {
+					callback.OnMessagesImported(importedMessages, totalMessages);
+				}
+				
+				batchedMessages.Clear();
+			}
+		}
+		
+		await target.Messages.Add(batchedMessages);
+		callback.OnMessagesImported(totalMessages, totalMessages);
+	}
+	
+	public interface IProgressCallback {
+		void OnImportingMetadata();
+		void OnMessagesImported(long finished, long total);
+		void OnDownloadsImported(long finished, long total);
+	}
+}

app/Server/Database/Import/FakeSnowflake.cs

@@ -11,7 +11,7 @@ public sealed class FakeSnowflake {
 	private ulong id;
 	
 	public FakeSnowflake() {
-		var unixMillis = (ulong) (DateTime.UtcNow.Subtract(DateTime.UnixEpoch).Ticks / TimeSpan.TicksPerMillisecond);
+		ulong unixMillis = (ulong) (DateTime.UtcNow.Subtract(DateTime.UnixEpoch).Ticks / TimeSpan.TicksPerMillisecond);
 		this.id = (unixMillis - DiscordEpoch) << 22;
 	}
 	

app/Server/Database/Import/LegacyArchiveImport.cs

@@ -20,24 +20,24 @@ public static class LegacyArchiveImport {
 	private static readonly FileExtensionContentTypeProvider ContentTypeProvider = new ();
 	
 	public static async Task<bool> Read(Stream stream, IDatabaseFile db, FakeSnowflake fakeSnowflake, Func<Data.Server[], Task<Dictionary<Data.Server, ulong>?>> askForServerIds) {
-		var perf = Log.Start();
+		Perf perf = Log.Start();
-		var root = await JsonSerializer.DeserializeAsync(stream, JsonElementContext.Default.JsonElement);
+		JsonElement root = await JsonSerializer.DeserializeAsync(stream, JsonElementContext.Default.JsonElement);
 		
 		try {
-			var meta = root.RequireObject("meta");
+			JsonElement meta = root.RequireObject("meta");
-			var data = root.RequireObject("data");
+			JsonElement data = root.RequireObject("data");
 			
 			perf.Step("Deserialize JSON");
 			
-			var users = ReadUserList(meta);
+			User[] users = ReadUserList(meta);
-			var servers = ReadServerList(meta, fakeSnowflake);
+			Data.Server[] servers = ReadServerList(meta, fakeSnowflake);
 			
 			var newServersOnly = new HashSet<Data.Server>(servers);
-			var oldServersById = await db.Servers.Get().ToDictionaryAsync(static server => server.Id, static server => server);
+			Dictionary<ulong, Data.Server> oldServersById = await db.Servers.Get().ToDictionaryAsync(static server => server.Id, static server => server);
-			var oldChannelsById = await db.Channels.Get().ToDictionaryAsync(static channel => channel.Id, static channel => channel);
+			Dictionary<ulong, Channel> oldChannelsById = await db.Channels.Get().ToDictionaryAsync(static channel => channel.Id, static channel => channel);
 			
-			foreach (var (channelId, serverIndex) in ReadChannelToServerIndexMapping(meta, servers)) {
+			foreach ((ulong channelId, int serverIndex) in ReadChannelToServerIndexMapping(meta, servers)) {
-				if (oldChannelsById.TryGetValue(channelId, out var oldChannel) && oldServersById.TryGetValue(oldChannel.Server, out var oldServer) && newServersOnly.Remove(servers[serverIndex])) {
+				if (oldChannelsById.TryGetValue(channelId, out Channel oldChannel) && oldServersById.TryGetValue(oldChannel.Server, out Data.Server oldServer) && newServersOnly.Remove(servers[serverIndex])) {
 					servers[serverIndex] = oldServer;
 				}
 			}
@@ -45,27 +45,27 @@ public static class LegacyArchiveImport {
 			perf.Step("Read server and user list");
 			
 			if (newServersOnly.Count > 0) {
-				var askedServerIds = await askForServerIds(newServersOnly.ToArray());
+				Dictionary<Data.Server, ulong>? askedServerIds = await askForServerIds(newServersOnly.ToArray());
 				if (askedServerIds == null) {
 					return false;
 				}
 				
 				perf.Step("Ask for server IDs");
 				
-				for (var i = 0; i < servers.Length; i++) {
+				for (int i = 0; i < servers.Length; i++) {
-					var server = servers[i];
+					Data.Server server = servers[i];
-					if (askedServerIds.TryGetValue(server, out var serverId)) {
+					if (askedServerIds.TryGetValue(server, out ulong serverId)) {
 						servers[i] = server with { Id = serverId };
 					}
 				}
 			}
 			
-			var channels = ReadChannelList(meta, servers);
+			Channel[] channels = ReadChannelList(meta, servers);
 			
 			perf.Step("Read channel list");
 			
-			var oldMessageIds = await db.Messages.GetIds().ToHashSetAsync();
+			HashSet<ulong> oldMessageIds = await db.Messages.GetIds().ToHashSetAsync();
-			var newMessages = channels.SelectMany(channel => ReadMessages(data, channel, users, fakeSnowflake))
+			Message[] newMessages = channels.SelectMany(channel => ReadMessages(data, channel, users, fakeSnowflake))
 			                                .Where(message => !oldMessageIds.Contains(message.Id))
 			                                .ToArray();
 			
@@ -92,21 +92,21 @@ public static class LegacyArchiveImport {
 			return ulong.Parse(element.GetString() ?? throw new JsonException("Expected key 'meta.userindex[" + index + "]' to be a string."));
 		}
 		
-		var userindex = meta.RequireArray("userindex", "meta")
+		Dictionary<ulong, int> userindex = meta.RequireArray("userindex", "meta")
 		                                       .Select(static (item, index) => (ParseUserIndex(item, index), index))
 		                                       .ToDictionary();
 		
 		var users = new User[userindex.Count];
 		
-		foreach (var item in meta.RequireObject("users", "meta").EnumerateObject()) {
+		foreach (JsonProperty item in meta.RequireObject("users", "meta").EnumerateObject()) {
-			var path = UsersPath + "." + item.Name;
+			string path = UsersPath + "." + item.Name;
-			var userId = ulong.Parse(item.Name);
+			ulong userId = ulong.Parse(item.Name);
-			var userObj = item.Value;
+			JsonElement userObj = item.Value;
 			
 			users[userindex[userId]] = new User {
 				Id = userId,
 				Name = userObj.RequireString("name", path),
-				AvatarUrl = userObj.HasKey("avatar") ? userObj.RequireString("avatar", path) : null,
+				AvatarHash = userObj.HasKey("avatar") ? userObj.RequireString("avatar", path) : null,
 				Discriminator = userObj.HasKey("tag") ? userObj.RequireString("tag", path) : null,
 			};
 		}
@@ -128,9 +128,9 @@ public static class LegacyArchiveImport {
 	
 	private static Dictionary<ulong, int> ReadChannelToServerIndexMapping(JsonElement meta, Data.Server[] servers) {
 		return meta.RequireObject("channels", "meta").EnumerateObject().Select(item => {
-			var path = ChannelsPath + "." + item.Name;
+			string path = ChannelsPath + "." + item.Name;
-			var channelId = ulong.Parse(item.Name);
+			ulong channelId = ulong.Parse(item.Name);
-			var channelObj = item.Value;
+			JsonElement channelObj = item.Value;
 			
 			return (channelId, channelObj.RequireInt("server", path, min: 0, max: servers.Length - 1));
 		}).ToDictionary();
@@ -138,13 +138,13 @@ public static class LegacyArchiveImport {
 	
 	private static Channel[] ReadChannelList(JsonElement meta, Data.Server[] servers) {
 		return meta.RequireObject("channels", "meta").EnumerateObject().Select(item => {
-			var path = ChannelsPath + "." + item.Name;
+			string path = ChannelsPath + "." + item.Name;
-			var channelId = ulong.Parse(item.Name);
+			ulong channelId = ulong.Parse(item.Name);
-			var channelObj = item.Value;
+			JsonElement channelObj = item.Value;
 			
 			return new Channel {
 				Id = channelId,
-				Server = servers[channelObj.RequireInt("server", path, min: 0, max: servers.Length - 1)].Id,
+				Server = servers[channelObj.RequireInt("server", path, min: 0, servers.Length - 1)].Id,
 				Name = channelObj.RequireString("name", path),
 				Position = channelObj.HasKey("position") ? channelObj.RequireInt("position", path, min: 0) : null,
 				Topic = channelObj.HasKey("topic") ? channelObj.RequireString("topic", path) : null,
@@ -156,18 +156,18 @@ public static class LegacyArchiveImport {
 	private static Message[] ReadMessages(JsonElement data, Channel channel, User[] users, FakeSnowflake fakeSnowflake) {
 		const string DataPath = "data";
 		
-		var channelId = channel.Id;
+		ulong channelId = channel.Id;
-		var channelIdStr = channelId.ToString();
+		string channelIdStr = channelId.ToString();
 		
-		var messagesObj = data.HasKey(channelIdStr) ? data.RequireObject(channelIdStr, DataPath) : (JsonElement?) null;
+		JsonElement? messagesObj = data.HasKey(channelIdStr) ? data.RequireObject(channelIdStr, DataPath) : null;
 		if (messagesObj == null) {
 			return [];
 		}
 		
 		return messagesObj.Value.EnumerateObject().Select(item => {
-			var path = DataPath + "." + item.Name;
+			string path = DataPath + "." + item.Name;
-			var messageId = ulong.Parse(item.Name);
+			ulong messageId = ulong.Parse(item.Name);
-			var messageObj = item.Value;
+			JsonElement messageObj = item.Value;
 			
 			return new Message {
 				Id = messageId,
@@ -189,7 +189,7 @@ public static class LegacyArchiveImport {
 		return attachmentsArray.Select(attachmentObj => {
 			string url = attachmentObj.RequireString("url", path);
 			string name = url[(url.LastIndexOf('/') + 1)..];
-			string? type = ContentTypeProvider.TryGetContentType(name, out var contentType) ? contentType : null;
+			string? type = ContentTypeProvider.TryGetContentType(name, out string? contentType) ? contentType : null;
 			
 			return new Attachment {
 				Id = fakeSnowflake.Next(),
@@ -216,19 +216,19 @@ public static class LegacyArchiveImport {
 				Type = type,
 				Title = type == "rich" && embedObj.HasKey("t") ? embedObj.RequireString("t", path) : null,
 				Description = type == "rich" && embedObj.HasKey("d") ? embedObj.RequireString("d", path) : null,
-				Image = type == "image" ? new DiscordEmbedLegacyJson.ImageJson { Url = url } : null
+				Image = type == "image" ? new DiscordEmbedLegacyJson.ImageJson { Url = url } : null,
 			};
 			
 			return new Embed {
-				Json = JsonSerializer.Serialize(embed, DiscordEmbedLegacyJsonContext.Default.DiscordEmbedLegacyJson)
+				Json = JsonSerializer.Serialize(embed, DiscordEmbedLegacyJsonContext.Default.DiscordEmbedLegacyJson),
 			};
 		});
 	}
 	
 	private static IEnumerable<Reaction> ReadMessageReactions(JsonElement.ArrayEnumerator reactionsArray, string path) {
 		return reactionsArray.Select(reactionObj => {
-			var id = reactionObj.HasKey("id") ? reactionObj.RequireSnowflake("id", path) : (ulong?) null;
+			ulong? id = reactionObj.HasKey("id") ? reactionObj.RequireSnowflake("id", path) : (ulong?) null;
-			var name = reactionObj.HasKey("n") ? reactionObj.RequireString("n", path) : null;
+			string? name = reactionObj.HasKey("n") ? reactionObj.RequireString("n", path) : null;
 			
 			if (id == null && name == null) {
 				throw new JsonException("Expected key '" + path + ".id' and/or '" + path + ".n' to be present.");

app/Server/Database/Repositories/IChannelRepository.cs

@@ -1,15 +1,14 @@
-using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using DHT.Server.Data;
+using DHT.Utils.Observables;
 
 namespace DHT.Server.Database.Repositories;
 
 public interface IChannelRepository {
-	IObservable<long> TotalCount { get; }
+	ObservableValue<long> TotalCount { get; }
 	
 	Task Add(IReadOnlyList<Channel> channels);
 	
@@ -17,8 +16,10 @@ public interface IChannelRepository {
 	
 	IAsyncEnumerable<Channel> Get(CancellationToken cancellationToken = default);
 	
+	Task<int> RemoveUnreachable();
+	
 	internal sealed class Dummy : IChannelRepository {
-		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
+		public ObservableValue<long> TotalCount { get; } = new (0L);
 		
 		public Task Add(IReadOnlyList<Channel> channels) {
 			return Task.CompletedTask;
@@ -31,5 +32,9 @@ public interface IChannelRepository {
 		public IAsyncEnumerable<Channel> Get(CancellationToken cancellationToken) {
 			return AsyncEnumerable.Empty<Channel>();
 		}
+		
+		public Task<int> RemoveUnreachable() {
+			return Task.FromResult(0);
+		}
 	}
 }

app/Server/Database/Repositories/IDownloadRepository.cs

@@ -2,25 +2,26 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
+using DHT.Server.Data;
 using DHT.Server.Data.Aggregations;
 using DHT.Server.Data.Filters;
 using DHT.Server.Download;
+using DHT.Utils.Observables;
 
 namespace DHT.Server.Database.Repositories;
 
 public interface IDownloadRepository {
-	IObservable<long> TotalCount { get; }
+	ObservableValue<long> TotalCount { get; }
 	
 	Task AddDownload(Data.Download item, Stream? stream);
 	
-	Task<long> Count(DownloadItemFilter filter, CancellationToken cancellationToken = default);
+	Task<long> Count(DownloadItemFilter? filter = null, CancellationToken cancellationToken = default);
 	
 	Task<DownloadStatusStatistics> GetStatistics(DownloadItemFilter nonSkippedFilter, CancellationToken cancellationToken = default);
 	
-	IAsyncEnumerable<Data.Download> Get();
+	IAsyncEnumerable<Data.Download> Get(DownloadItemFilter? filter = null);
 	
 	Task<bool> GetDownloadData(string normalizedUrl, Func<Stream, Task> dataProcessor);
 	
@@ -32,14 +33,18 @@ public interface IDownloadRepository {
 	
 	Task<int> RetryFailed(CancellationToken cancellationToken = default);
 	
+	Task Remove(ICollection<string> normalizedUrls);
+	
+	IAsyncEnumerable<FileUrl> FindReachableFiles(CancellationToken cancellationToken = default);
+	
 	internal sealed class Dummy : IDownloadRepository {
-		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
+		public ObservableValue<long> TotalCount { get; } = new (0L);
 		
 		public Task AddDownload(Data.Download item, Stream? stream) {
 			return Task.CompletedTask;
 		}
 		
-		public Task<long> Count(DownloadItemFilter filter, CancellationToken cancellationToken) {
+		public Task<long> Count(DownloadItemFilter? filter, CancellationToken cancellationToken) {
 			return Task.FromResult(0L);
 		}
 		
@@ -47,7 +52,7 @@ public interface IDownloadRepository {
 			return Task.FromResult(new DownloadStatusStatistics());
 		}
 		
-		public IAsyncEnumerable<Data.Download> Get() {
+		public IAsyncEnumerable<Data.Download> Get(DownloadItemFilter? filter) {
 			return AsyncEnumerable.Empty<Data.Download>();
 		}
 		
@@ -70,5 +75,13 @@ public interface IDownloadRepository {
 		public Task<int> RetryFailed(CancellationToken cancellationToken) {
 			return Task.FromResult(0);
 		}
+		
+		public Task Remove(ICollection<string> normalizedUrls) {
+			return Task.CompletedTask;
+		}
+		
+		public IAsyncEnumerable<FileUrl> FindReachableFiles(CancellationToken cancellationToken) {
+			return AsyncEnumerable.Empty<FileUrl>();
+		}
 	}
 }

app/Server/Database/Repositories/IMessageRepository.cs

@@ -1,16 +1,15 @@
-using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using DHT.Server.Data;
 using DHT.Server.Data.Filters;
+using DHT.Utils.Observables;
 
 namespace DHT.Server.Database.Repositories;
 
 public interface IMessageRepository {
-	IObservable<long> TotalCount { get; }
+	ObservableValue<long> TotalCount { get; }
 	
 	Task Add(IReadOnlyList<Message> messages);
 	
@@ -20,10 +19,12 @@ public interface IMessageRepository {
 	
 	IAsyncEnumerable<ulong> GetIds(MessageFilter? filter = null);
 	
-	Task Remove(MessageFilter filter, FilterRemovalMode mode);
+	Task<int> Remove(MessageFilter filter, FilterRemovalMode mode);
+	
+	Task<int> RemoveUnreachableAttachments();
 	
 	internal sealed class Dummy : IMessageRepository {
-		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
+		public ObservableValue<long> TotalCount { get; } = new (0L);
 		
 		public Task Add(IReadOnlyList<Message> messages) {
 			return Task.CompletedTask;
@@ -41,8 +42,12 @@ public interface IMessageRepository {
 			return AsyncEnumerable.Empty<ulong>();
 		}
 		
-		public Task Remove(MessageFilter filter, FilterRemovalMode mode) {
+		public Task<int> Remove(MessageFilter filter, FilterRemovalMode mode) {
-			return Task.CompletedTask;
+			return Task.FromResult(0);
+		}
+		
+		public Task<int> RemoveUnreachableAttachments() {
+			return Task.FromResult(0);
 		}
 	}
 }

app/Server/Database/Repositories/IServerRepository.cs

@@ -1,14 +1,13 @@
-using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
+using DHT.Utils.Observables;
 
 namespace DHT.Server.Database.Repositories;
 
 public interface IServerRepository {
-	IObservable<long> TotalCount { get; }
+	ObservableValue<long> TotalCount { get; }
 	
 	Task Add(IReadOnlyList<Data.Server> servers);
 	
@@ -16,8 +15,10 @@ public interface IServerRepository {
 	
 	IAsyncEnumerable<Data.Server> Get(CancellationToken cancellationToken = default);
 	
+	Task<int> RemoveUnreachable();
+	
 	internal sealed class Dummy : IServerRepository {
-		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
+		public ObservableValue<long> TotalCount { get; } = new (0L);
 		
 		public Task Add(IReadOnlyList<Data.Server> servers) {
 			return Task.CompletedTask;
@@ -30,5 +31,9 @@ public interface IServerRepository {
 		public IAsyncEnumerable<Data.Server> Get(CancellationToken cancellationToken) {
 			return AsyncEnumerable.Empty<Data.Server>();
 		}
+		
+		public Task<int> RemoveUnreachable() {
+			return Task.FromResult(0);
+		}
 	}
 }

app/Server/Database/Repositories/IUserRepository.cs

@@ -1,15 +1,14 @@
-using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using DHT.Server.Data;
+using DHT.Utils.Observables;
 
 namespace DHT.Server.Database.Repositories;
 
 public interface IUserRepository {
-	IObservable<long> TotalCount { get; }
+	ObservableValue<long> TotalCount { get; }
 	
 	Task Add(IReadOnlyList<User> users);
 	
@@ -17,8 +16,10 @@ public interface IUserRepository {
 	
 	IAsyncEnumerable<User> Get(CancellationToken cancellationToken = default);
 	
+	Task<int> RemoveUnreachable();
+	
 	internal sealed class Dummy : IUserRepository {
-		public IObservable<long> TotalCount { get; } = Observable.Return(0L);
+		public ObservableValue<long> TotalCount { get; } = new (0L);
 		
 		public Task Add(IReadOnlyList<User> users) {
 			return Task.CompletedTask;
@@ -31,5 +32,9 @@ public interface IUserRepository {
 		public IAsyncEnumerable<User> Get(CancellationToken cancellationToken) {
 			return AsyncEnumerable.Empty<User>();
 		}
+		
+		public Task<int> RemoveUnreachable() {
+			return Task.FromResult(0);
+		}
 	}
 }

app/Server/Database/Sqlite/Repositories/BaseSqliteRepository.cs

@@ -1,23 +1,27 @@
 using System;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using DHT.Utils.Logging;
+using DHT.Utils.Observables;
 using DHT.Utils.Tasks;
 
 namespace DHT.Server.Database.Sqlite.Repositories;
 
 abstract class BaseSqliteRepository : IDisposable {
-	private readonly ObservableThrottledTask<long> totalCountTask;
+	private readonly ThrottledTask<long> totalCountTask;
 	
-	public IObservable<long> TotalCount { get; }
+	public ObservableValue<long> TotalCount { get; } = new (0L);
 	
 	protected BaseSqliteRepository(Log log) {
-		totalCountTask = new ObservableThrottledTask<long>(log, TaskScheduler.Default);
+		totalCountTask = new ThrottledTask<long>(log, SetTotalCount, TimeSpan.Zero, TaskScheduler.Default);
-		TotalCount = totalCountTask.DistinctUntilChanged();
 		UpdateTotalCount();
 	}
 	
+	private Task SetTotalCount(long newCount) {
+		TotalCount.Set(newCount);
+		return Task.CompletedTask;
+	}
+	
 	public void Dispose() {
 		totalCountTask.Dispose();
 	}

app/Server/Database/Sqlite/Repositories/SqliteChannelRepository.cs

@@ -30,10 +30,10 @@ sealed class SqliteChannelRepository : BaseSqliteRepository, IChannelRepository
 				("parent_id", SqliteType.Integer),
 				("position", SqliteType.Integer),
 				("topic", SqliteType.Text),
-				("nsfw", SqliteType.Integer)
+				("nsfw", SqliteType.Integer),
 			]);
 			
-			foreach (var channel in channels) {
+			foreach (Channel channel in channels) {
 				cmd.Set(":id", channel.Id);
 				cmd.Set(":server", channel.Server);
 				cmd.Set(":name", channel.Name);
@@ -73,4 +73,14 @@ sealed class SqliteChannelRepository : BaseSqliteRepository, IChannelRepository
 			};
 		}
 	}
+	
+	public async Task<int> RemoveUnreachable() {
+		int removed;
+		await using (var conn = await pool.Take()) {
+			removed = await conn.ExecuteAsync("DELETE FROM channels WHERE id NOT IN (SELECT DISTINCT channel_id FROM messages)");
+		}
+		
+		UpdateTotalCount();
+		return removed;
+	}
 }

app/Server/Database/Sqlite/Repositories/SqliteDownloadRepository.cs

@@ -18,6 +18,8 @@ namespace DHT.Server.Database.Sqlite.Repositories;
 sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRepository(Log), IDownloadRepository {
 	private static readonly Log Log = Log.ForType<SqliteDownloadRepository>();
 	
+	public const string Schema = "downloads";
+	
 	internal sealed class NewDownloadCollector : IAsyncDisposable {
 		private readonly SqliteDownloadRepository repository;
 		private bool hasChanged = false;
@@ -60,6 +62,15 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 			hasChanged |= await metadataCmd.ExecuteNonQueryAsync() > 0;
 		}
 		
+		public Task AddIfNotNull(Data.Download? download) {
+			if (download != null) {
+				return Add(download);
+			}
+			else {
+				return Task.CompletedTask;
+			}
+		}
+		
 		public void OnCommitted() {
 			if (hasChanged) {
 				repository.UpdateTotalCount();
@@ -71,7 +82,25 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 		}
 	}
 	
+	private static SqliteBlob BlobReference(ISqliteConnection conn, long rowid, bool readOnly) {
+		string schema = conn.HasAttachedDatabase(Schema) ? Schema : "main";
+		return new SqliteBlob(conn.InnerConnection, databaseName: schema, tableName: "download_blobs", columnName: "blob", rowid, readOnly);
+	}
+	
 	public async Task AddDownload(Data.Download item, Stream? stream) {
+		ulong? actualSize;
+		
+		if (stream is not null) {
+			actualSize = (ulong) stream.Length;
+			
+			if (actualSize != item.Size) {
+				Log.Warn("Download size differs from its metadata - metadata size: " + item.Size + " B, actual size: " + actualSize + " B, url: " + item.NormalizedUrl);
+			}
+		}
+		else {
+			actualSize = item.Size;
+		}
+		
 		await using (var conn = await pool.Take()) {
 			await conn.BeginTransactionAsync();
 			
@@ -87,7 +116,7 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 			metadataCmd.Set(":download_url", item.DownloadUrl);
 			metadataCmd.Set(":status", (int) item.Status);
 			metadataCmd.Set(":type", item.Type);
-			metadataCmd.Set(":size", item.Size);
+			metadataCmd.Set(":size", actualSize);
 			await metadataCmd.ExecuteNonQueryAsync();
 			
 			if (stream == null) {
@@ -107,10 +136,10 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 				);
 				
 				upsertBlobCmd.AddAndSet(":normalized_url", SqliteType.Text, item.NormalizedUrl);
-				upsertBlobCmd.AddAndSet(":blob_length", SqliteType.Integer, item.Size);
+				upsertBlobCmd.AddAndSet(":blob_length", SqliteType.Integer, actualSize);
 				long rowid = await upsertBlobCmd.ExecuteLongScalarAsync();
 				
-				await using var blob = new SqliteBlob(conn.InnerConnection, "download_blobs", "blob", rowid);
+				await using var blob = BlobReference(conn, rowid, readOnly: false);
 				await stream.CopyToAsync(blob);
 			}
 			
@@ -177,14 +206,14 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 			FailedWithUnknownSizeCount = reader.GetInt32(8),
 			SkippedCount = reader.GetInt32(9),
 			SkippedTotalSize = reader.GetUint64(10),
-			SkippedWithUnknownSizeCount = reader.GetInt32(11)
+			SkippedWithUnknownSizeCount = reader.GetInt32(11),
 		};
 	}
 	
-	public async IAsyncEnumerable<Data.Download> Get() {
+	public async IAsyncEnumerable<Data.Download> Get(DownloadItemFilter? filter) {
 		await using var conn = await pool.Take();
 		
-		await using var cmd = conn.Command("SELECT normalized_url, download_url, status, type, size FROM download_metadata");
+		await using var cmd = conn.Command("SELECT normalized_url, download_url, status, type, size FROM download_metadata" + filter.GenerateConditions().BuildWhereClause());
 		await using var reader = await cmd.ExecuteReaderAsync();
 		
 		while (await reader.ReadAsync()) {
@@ -206,7 +235,7 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 		
 		long rowid;
 		
-		await using (var reader = await cmd.ExecuteReaderAsync()) {
+		await using (SqliteDataReader reader = await cmd.ExecuteReaderAsync()) {
 			if (!await reader.ReadAsync()) {
 				return false;
 			}
@@ -214,7 +243,7 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 			rowid = reader.GetInt64(0);
 		}
 		
-		await using (var blob = new SqliteBlob(conn.InnerConnection, "download_blobs", "blob", rowid, readOnly: true)) {
+		await using (var blob = BlobReference(conn, rowid, readOnly: true)) {
 			await dataProcessor(blob);
 		}
 		
@@ -249,7 +278,7 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 			rowid = reader.GetInt64(2);
 		}
 		
-		await using (var blob = new SqliteBlob(conn.InnerConnection, "download_blobs", "blob", rowid, readOnly: true)) {
+		await using (var blob = BlobReference(conn, rowid, readOnly: true)) {
 			await dataProcessor(new Data.Download(normalizedUrl, downloadUrl, DownloadStatus.Success, type, (ulong) blob.Length), blob, cancellationToken);
 		}
 		
@@ -264,7 +293,7 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 		
 		await using var conn = await pool.Take();
 		
-		var sql = $"""
+		string sql = $"""
 		              SELECT normalized_url, download_url, type, size
 		              FROM download_metadata
 		              {filter.GenerateConditions().BuildWhereClause()}
@@ -272,17 +301,19 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 		              """;
 		
 		await using (var cmd = conn.Command(sql)) {
-			cmd.AddAndSet(":limit", SqliteType.Integer, Math.Max(0, count));
+			cmd.AddAndSet(":limit", SqliteType.Integer, Math.Max(val1: 0, count));
 			
 			await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
 			
 			while (await reader.ReadAsync(cancellationToken)) {
-				found.Add(new DownloadItem {
+				var item = new DownloadItem(
-					NormalizedUrl = reader.GetString(0),
+					NormalizedUrl: reader.GetString(0),
-					DownloadUrl = reader.GetString(1),
+					DownloadUrl: reader.GetString(1),
-					Type = reader.IsDBNull(2) ? null : reader.GetString(2),
+					Type: reader.IsDBNull(2) ? null : reader.GetString(2),
-					Size = reader.IsDBNull(3) ? null : reader.GetUint64(3)
+					Size: reader.IsDBNull(3) ? null : reader.GetUint64(3)
-				});
+				);
+				
+				found.Add(item);
 			}
 		}
 		
@@ -292,7 +323,7 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 			cmd.AddAndSet(":downloading", SqliteType.Integer, (int) DownloadStatus.Downloading);
 			cmd.Add(":normalized_url", SqliteType.Text);
 			
-			foreach (var item in found) {
+			foreach (DownloadItem item in found) {
 				cmd.Set(":normalized_url", item.NormalizedUrl);
 				
 				if (await cmd.ExecuteNonQueryAsync(cancellationToken) == 1) {
@@ -321,4 +352,82 @@ sealed class SqliteDownloadRepository(SqliteConnectionPool pool) : BaseSqliteRep
 		cmd.AddAndSet(":success", SqliteType.Integer, (int) DownloadStatus.Success);
 		return await cmd.ExecuteNonQueryAsync(cancellationToken);
 	}
+	
+	public async Task Remove(ICollection<string> normalizedUrls) {
+		await using (var conn = await pool.Take()) {
+			await conn.BeginTransactionAsync();
+			
+			await using (var cmd = conn.Command("DELETE FROM download_metadata WHERE normalized_url = :normalized_url")) {
+				cmd.Add(":normalized_url", SqliteType.Text);
+				
+				foreach (string normalizedUrl in normalizedUrls) {
+					cmd.Set(":normalized_url", normalizedUrl);
+					await cmd.ExecuteNonQueryAsync();
+				}
+			}
+			
+			await conn.CommitTransactionAsync();
+		}
+		
+		UpdateTotalCount();
+	}
+	
+	public async IAsyncEnumerable<FileUrl> FindReachableFiles([EnumeratorCancellation] CancellationToken cancellationToken) {
+		await using var conn = await pool.Take();
+		
+		await using (var cmd = conn.Command("SELECT type, normalized_url, download_url FROM attachments")) {
+			await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
+			
+			while (await reader.ReadAsync(cancellationToken)) {
+				string? type = reader.IsDBNull(0) ? null : reader.GetString(0);
+				string normalizedUrl = reader.GetString(1);
+				string downloadUrl = reader.GetString(2);
+				yield return new FileUrl(normalizedUrl, downloadUrl, type);
+			}
+		}
+		
+		await using (var cmd = conn.Command("SELECT json FROM message_embeds")) {
+			await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
+			
+			while (await reader.ReadAsync(cancellationToken)) {
+				if (await DownloadLinkExtractor.TryFromEmbedJson(reader.GetStream(0)) is {} result) {
+					yield return result;
+				}
+			}
+		}
+		
+		await using (var cmd = conn.Command("SELECT DISTINCT emoji_id, emoji_flags FROM message_reactions WHERE emoji_id IS NOT NULL")) {
+			await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
+			
+			while (await reader.ReadAsync(cancellationToken)) {
+				ulong emojiId = reader.GetUint64(0);
+				EmojiFlags emojiFlags = (EmojiFlags) reader.GetInt16(1);
+				yield return DownloadLinkExtractor.Emoji(emojiId, emojiFlags);
+			}
+		}
+		
+		await using (var cmd = conn.Command("SELECT id, type, icon_hash FROM servers WHERE icon_hash IS NOT NULL")) {
+			await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
+			
+			while (await reader.ReadAsync(cancellationToken)) {
+				ulong id = reader.GetUint64(0);
+				ServerType? type = ServerTypes.FromString(reader.GetString(1));
+				string iconHash = reader.GetString(2);
+				
+				if (DownloadLinkExtractor.ServerIcon(type, id, iconHash) is {} result) {
+					yield return result;
+				}
+			}
+		}
+		
+		await using (var cmd = conn.Command("SELECT id, avatar_url FROM users WHERE avatar_url IS NOT NULL")) {
+			await using var reader = await cmd.ExecuteReaderAsync(cancellationToken);
+			
+			while (await reader.ReadAsync(cancellationToken)) {
+				ulong id = reader.GetUint64(0);
+				string avatarHash = reader.GetString(1);
+				yield return DownloadLinkExtractor.UserAvatar(id, avatarHash);
+			}
+		}
+	}
 }