Release v38.0

Closes #226

README.md

@@ -19,7 +19,7 @@ Folder organization:
 * `lib/` contains utilities required to build the project
 * `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 5 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/5.0), 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 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/).
 
 ### Building
 
@@ -50,6 +50,6 @@ Run the `app/build.sh` script, and read the [Distribution](#distribution) sectio
 
 #### 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 5 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 .NET 8 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 `DiscordHistoryTracker`. I tried using Python to re-create the archives with correct file permissions, but found that Linux `zip` tools could not see them. The only working solution is building the Windows + portable version on Windows, and Linux + Mac version on Linux.

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

@@ -7,12 +7,15 @@
         <entry key="Desktop/Dialogs/CheckBox/CheckBoxDialog.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Dialogs/Message/MessageDialog.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Dialogs/Progress/ProgressDialog.axaml" value="Desktop/Desktop.csproj" />
+        <entry key="Desktop/Dialogs/TextBox/TextBoxDialog.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/AboutWindow.axaml" value="Desktop/Desktop.csproj" />
-        <entry key="Desktop/Main/Controls/FilterPanel.axaml" value="Desktop/Desktop.csproj" />
+        <entry key="Desktop/Main/Controls/AttachmentFilterPanel.axaml" value="Desktop/Desktop.csproj" />
+        <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/MainWindow.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/AdvancedPage.axaml" value="Desktop/Desktop.csproj" />
+        <entry key="Desktop/Main/Pages/AttachmentsPage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/DatabasePage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/DebugPage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/TrackingPage.axaml" value="Desktop/Desktop.csproj" />

app/Desktop/App.axaml

@@ -6,7 +6,8 @@
 
     <Application.Styles>
 
-        <FluentTheme Mode="Light" />
+        <FluentTheme />
+        <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Simple.xaml" />
 
         <Style Selector="Button, CheckBox, RadioButton, Expander /template/ ToggleButton#ExpanderHeader">
             <Setter Property="Cursor" Value="Hand" />
@@ -32,79 +33,32 @@
         <Style Selector="TextBox:focus /template/ Border#PART_BorderElement">
             <Setter Property="BorderThickness" Value="1" />
         </Style>
-        <Style Selector="TextBox:disabled"><!-- TODO bug in Avalonia (https://github.com/AvaloniaUI/Avalonia/pull/7792) -->
-            <Setter Property="Foreground" Value="{DynamicResource TextControlForegroundDisabled}" />
-        </Style>
-
-        <Style Selector="Expander /template/ ToggleButton#ExpanderHeader">
-            <Setter Property="HorizontalContentAlignment" Value="Left" />
-            <Setter Property="Template">
-                <ControlTemplate>
-                    <Border x:Name="ToggleButtonBackground">
-                        <Grid ColumnDefinitions="Auto,*" RowDefinitions="35">
-                            <Border x:Name="ExpandCollapseChevronBorder"
-                                    Grid.Column="0"
-                                    Width="35"
-                                    Height="35"
-                                    Margin="2,0"
-                                    RenderTransformOrigin="50%,50%">
-                                <Path x:Name="ExpandCollapseChevron"
-                                      HorizontalAlignment="Center"
-                                      VerticalAlignment="Center"
-                                      RenderTransformOrigin="50%,50%"
-                                      Stretch="None"
-                                      Stroke="{DynamicResource ExpanderChevronForeground}"
-                                      StrokeThickness="1" />
-                                <Border.RenderTransform>
-                                    <RotateTransform />
-                                </Border.RenderTransform>
-                            </Border>
-                            <ContentPresenter x:Name="PART_ContentPresenter"
-                                              Grid.Column="1"
-                                              Margin="0"
-                                              HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
-                                              VerticalContentAlignment="Center"
-                                              Background="Transparent"
-                                              BorderBrush="Transparent"
-                                              BorderThickness="0"
-                                              Content="{TemplateBinding Content}"
-                                              ContentTemplate="{TemplateBinding ContentTemplate}"
-                                              TextBlock.Foreground="{DynamicResource ExpanderForeground}" />
-                        </Grid>
-                    </Border>
+        <Style Selector="TextBox:error DataValidationErrors">
+            <Style.Resources>
+                <ControlTemplate x:Key="InlineDataValidationContentTemplate" TargetType="DataValidationErrors">
+                    <ContentPresenter Name="PART_ContentPresenter"
+                                      Padding="{TemplateBinding Padding}"
+                                      Background="{TemplateBinding Background}"
+                                      BorderThickness="{TemplateBinding BorderThickness}"
+                                      CornerRadius="{TemplateBinding CornerRadius}"
+                                      Content="{TemplateBinding Content}"
+                                      ContentTemplate="{TemplateBinding ContentTemplate}" />
                 </ControlTemplate>
-            </Setter>
-        </Style>
-        <Style Selector="Expander:expanded /template/ ToggleButton#ExpanderHeader /template/ Border#ExpandCollapseChevronBorder">
-            <Style.Animations>
-                <Animation FillMode="Both" Duration="0:0:0.0625">
-                    <KeyFrame Cue="0%">
-                        <Setter Property="RotateTransform.Angle" Value="180" />
-                    </KeyFrame>
-                    <KeyFrame Cue="100%">
-                        <Setter Property="RotateTransform.Angle" Value="180" />
-                    </KeyFrame>
-                </Animation>
-            </Style.Animations>
-        </Style>
-        <Style Selector="Expander:not(:expanded) /template/ ToggleButton#ExpanderHeader /template/ Border#ExpandCollapseChevronBorder">
-            <Style.Animations>
-                <Animation FillMode="Both" Duration="0:0:0.0625">
-                    <KeyFrame Cue="0%">
-                        <Setter Property="RotateTransform.Angle" Value="0" />
-                    </KeyFrame>
-                    <KeyFrame Cue="100%">
-                        <Setter Property="RotateTransform.Angle" Value="0" />
-                    </KeyFrame>
-                </Animation>
-            </Style.Animations>
+            </Style.Resources>
+            <Setter Property="Template" Value="{StaticResource InlineDataValidationContentTemplate}" />
         </Style>
 
+        <Style Selector="Expander">
+            <Setter Property="MinHeight" Value="40" />
+            <Setter Property="HorizontalAlignment" Value="Stretch" />
+        </Style>
+        
     </Application.Styles>
 
     <Application.Resources>
 
         <common:NumberValueConverter x:Key="NumberValueConverter" />
+        <common:BytesValueConverter x:Key="BytesValueConverter" />
 
         <system:Double x:Key="ControlContentThemeFontSize">14</system:Double>
         <CornerRadius x:Key="ControlCornerRadius">0</CornerRadius>
@@ -152,15 +106,29 @@
         <SolidColorBrush x:Key="TextControlPlaceholderForegroundPointerOver" Color="#AAAAAA" />
         <SolidColorBrush x:Key="TextControlPlaceholderForegroundFocused" Color="#AAAAAA" />
         <SolidColorBrush x:Key="TextControlPlaceholderForegroundDisabled" Color="#AAAAAA" />
-
+        
         <Thickness x:Key="ExpanderHeaderPadding">15,0</Thickness>
-        <Thickness x:Key="ExpanderContentPadding">15</Thickness>
-        <SolidColorBrush x:Key="ExpanderBorderBrush" Color="#697DAB" />
-        <SolidColorBrush x:Key="ExpanderBackground" Color="#697DAB" />
-        <SolidColorBrush x:Key="ExpanderForeground" Color="#FFFFFF" />
+        <Thickness x:Key="ExpanderContentPadding">12</Thickness>
+        <SolidColorBrush x:Key="ExpanderHeaderBorderBrush" Color="#697DAB" />
+        <SolidColorBrush x:Key="ExpanderHeaderBorderBrushPointerOver" Color="#697DAB" />
+        <SolidColorBrush x:Key="ExpanderHeaderBorderBrushPressed" Color="#697DAB" />
+        <SolidColorBrush x:Key="ExpanderHeaderBorderBrushDisabled" Color="#697DAB" />
+        <SolidColorBrush x:Key="ExpanderHeaderBackground" Color="#697DAB" />
+        <SolidColorBrush x:Key="ExpanderHeaderBackgroundPointerOver" Color="#536794" />
+        <SolidColorBrush x:Key="ExpanderHeaderBackgroundPressed" Color="#47587F" />
+        <SolidColorBrush x:Key="ExpanderHeaderBackgroundDisabled" Color="#697DAB" />
+        <SolidColorBrush x:Key="ExpanderHeaderForeground" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderHeaderForegroundPointerOver" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderHeaderForegroundPressed" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderHeaderForegroundDisabled" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderChevronBackground" Color="Transparent" />
+        <SolidColorBrush x:Key="ExpanderChevronBackgroundPointerOver" Color="#536794" />
+        <SolidColorBrush x:Key="ExpanderChevronBackgroundPressed" Color="#47587F" />
+        <SolidColorBrush x:Key="ExpanderChevronBackgroundDisabled" Color="Transparent" />
         <SolidColorBrush x:Key="ExpanderChevronForeground" Color="#FFFFFF" />
-        <SolidColorBrush x:Key="ExpanderDropDownBorderBrush" Color="#697DAB" />
-        <SolidColorBrush x:Key="ExpanderDropDownBackground" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderChevronForegroundPointerOver" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderChevronForegroundPressed" Color="#FFFFFF" />
+        <SolidColorBrush x:Key="ExpanderChevronForegroundDisabled" Color="#FFFFFF" />
 
     </Application.Resources>
 

app/Desktop/App.axaml.cs

@@ -1,20 +1,21 @@
+using System;
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Markup.Xaml;
 using DHT.Desktop.Main;
 
-namespace DHT.Desktop {
-	sealed class App : Application {
-		public override void Initialize() {
-			AvaloniaXamlLoader.Load(this);
+namespace DHT.Desktop;
+
+sealed class App : Application {
+	public override void Initialize() {
+		AvaloniaXamlLoader.Load(this);
+	}
+
+	public override void OnFrameworkInitializationCompleted() {
+		if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop) {
+			desktop.MainWindow = new MainWindow(new Arguments(desktop.Args ?? Array.Empty<string>()));
 		}
 
-		public override void OnFrameworkInitializationCompleted() {
-			if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop) {
-				desktop.MainWindow = new MainWindow(new Arguments(desktop.Args));
-			}
-
-			base.OnFrameworkInitializationCompleted();
-		}
+		base.OnFrameworkInitializationCompleted();
 	}
 }

app/Desktop/Arguments.cs

@@ -1,64 +1,64 @@
 using System;
 using DHT.Utils.Logging;
 
-namespace DHT.Desktop {
-	sealed class Arguments {
-		private static readonly Log Log = Log.ForType<Arguments>();
+namespace DHT.Desktop;
 
-		public static Arguments Empty => new(Array.Empty<string>());
+sealed class Arguments {
+	private static readonly Log Log = Log.ForType<Arguments>();
 
-		public string? DatabaseFile { get; }
-		public ushort? ServerPort { get; }
-		public string? ServerToken { get; }
+	public static Arguments Empty => new(Array.Empty<string>());
 
-		public Arguments(string[] args) {
-			for (int i = 0; i < args.Length; i++) {
-				string key = args[i];
+	public string? DatabaseFile { get; }
+	public ushort? ServerPort { get; }
+	public string? ServerToken { get; }
 
-				switch (key) {
-					case "-debug":
-						Log.IsDebugEnabled = true;
-						continue;
-				}
+	public Arguments(string[] args) {
+		for (int i = 0; i < args.Length; i++) {
+			string key = args[i];
 
-				string value;
-
-				if (i == 0 && !key.StartsWith('-')) {
-					value = key;
-					key = "-db";
-				}
-				else if (i >= args.Length - 1) {
-					Log.Warn("Missing value for command line argument: " + key);
+			switch (key) {
+				case "-debug":
+					Log.IsDebugEnabled = true;
 					continue;
-				}
-				else {
-					value = args[++i];
-				}
+			}
 
-				switch (key) {
-					case "-db":
-						DatabaseFile = value;
-						continue;
+			string value;
 
-					case "-port": {
-						if (ushort.TryParse(value, out var port)) {
-							ServerPort = port;
-						}
-						else {
-							Log.Warn("Invalid port number: " + value);
-						}
+			if (i == 0 && !key.StartsWith('-')) {
+				value = key;
+				key = "-db";
+			}
+			else if (i >= args.Length - 1) {
+				Log.Warn("Missing value for command line argument: " + key);
+				continue;
+			}
+			else {
+				value = args[++i];
+			}
 
-						continue;
+			switch (key) {
+				case "-db":
+					DatabaseFile = value;
+					continue;
+
+				case "-port": {
+					if (ushort.TryParse(value, out var port)) {
+						ServerPort = port;
+					}
+					else {
+						Log.Warn("Invalid port number: " + value);
 					}
 
-					case "-token":
-						ServerToken = value;
-						continue;
-
-					default:
-						Log.Warn("Unknown command line argument: " + key);
-						break;
+					continue;
 				}
+
+				case "-token":
+					ServerToken = value;
+					continue;
+
+				default:
+					Log.Warn("Unknown command line argument: " + key);
+					break;
 			}
 		}
 	}

app/Desktop/Common/BytesValueConverter.cs

@@ -0,0 +1,53 @@
+using System;
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace DHT.Desktop.Common;
+
+sealed class BytesValueConverter : IValueConverter {
+	private sealed class Unit {
+		private readonly string label;
+		private readonly string numberFormat;
+
+		public Unit(string label, int decimalPlaces) {
+			this.label = label;
+			this.numberFormat = "{0:n" + decimalPlaces + "}";
+		}
+
+		public string Format(double size) {
+			return string.Format(Program.Culture, numberFormat, size) + " " + label;
+		}
+	}
+
+	private static readonly Unit[] Units = {
+		new ("B", decimalPlaces: 0),
+		new ("kB", decimalPlaces: 0),
+		new ("MB", decimalPlaces: 1),
+		new ("GB", decimalPlaces: 1),
+		new ("TB", decimalPlaces: 1)
+	};
+
+	private const int Scale = 1000;
+
+	private static string Convert(ulong size) {
+		int power = size == 0L ? 0 : (int) Math.Log(size, Scale);
+		int unit = power >= Units.Length ? Units.Length - 1 : power;
+		return Units[unit].Format(unit == 0 ? size : size / Math.Pow(Scale, unit));
+	}
+
+	public object Convert(object? value, Type targetType, object? parameter, CultureInfo culture) {
+		if (value is long size and >= 0L) {
+			return Convert((ulong) size);
+		}
+		else if (value is ulong usize) {
+			return Convert(usize);
+		}
+		else {
+			return "-";
+		}
+	}
+
+	public object ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture) {
+		throw new NotSupportedException();
+	}
+}

app/Desktop/Common/DatabaseGui.cs

@@ -3,64 +3,66 @@ using System.Collections.Generic;
 using System.IO;
 using System.Threading.Tasks;
 using Avalonia.Controls;
+using Avalonia.Platform.Storage;
+using DHT.Desktop.Dialogs.File;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Server.Database;
 using DHT.Server.Database.Exceptions;
 using DHT.Server.Database.Sqlite;
 using DHT.Utils.Logging;
 
-namespace DHT.Desktop.Common {
-	static class DatabaseGui {
-		private static readonly Log Log = Log.ForType(typeof(DatabaseGui));
+namespace DHT.Desktop.Common;
 
-		private const string DatabaseFileInitialName = "archive.dht";
+static class DatabaseGui {
+	private static readonly Log Log = Log.ForType(typeof(DatabaseGui));
 
-		private static readonly List<FileDialogFilter> DatabaseFileDialogFilter = new() {
-			new FileDialogFilter {
-				Name = "Discord History Tracker Database",
-				Extensions = { "dht" }
-			}
-		};
+	private const string DatabaseFileInitialName = "archive.dht";
 
-		public static OpenFileDialog NewOpenDatabaseFileDialog() {
-			return new OpenFileDialog {
-				Title = "Open Database File",
-				InitialFileName = DatabaseFileInitialName,
-				Filters = DatabaseFileDialogFilter
-			};
+	private static readonly IReadOnlyList<FilePickerFileType> DatabaseFileDialogFilter = new List<FilePickerFileType> {
+		FileDialogs.CreateFilter("Discord History Tracker Database", new [] { "dht" })
+	};
+
+	public static async Task<string[]> NewOpenDatabaseFilesDialog(Window window, string? suggestedDirectory) {
+		return await window.StorageProvider.OpenFiles(new FilePickerOpenOptions {
+			Title = "Open Database File",
+			FileTypeFilter = DatabaseFileDialogFilter,
+			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, suggestedDirectory),
+			AllowMultiple = true
+		});
+	}
+
+	public static async Task<string?> NewOpenOrCreateDatabaseFileDialog(Window window, string? suggestedDirectory) {
+		return await window.StorageProvider.SaveFile(new FilePickerSaveOptions {
+			Title = "Open or Create Database File",
+			FileTypeChoices = DatabaseFileDialogFilter,
+			SuggestedFileName = DatabaseFileInitialName,
+			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, suggestedDirectory),
+			ShowOverwritePrompt = false
+		});
+	}
+
+	public static async Task<IDatabaseFile?> TryOpenOrCreateDatabaseFromPath(string path, Window window, Func<Task<bool>> checkCanUpgradeDatabase) {
+		IDatabaseFile? file = null;
+
+		try {
+			file = await SqliteDatabaseFile.OpenOrCreate(path, checkCanUpgradeDatabase);
+		} catch (InvalidDatabaseVersionException ex) {
+			await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' appears to be corrupted (invalid version: " + ex.Version + ").");
+		} 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);
+			await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' could not be opened:" + ex.Message);
 		}
 
-		public static SaveFileDialog NewOpenOrCreateDatabaseFileDialog() {
-			return new SaveFileDialog {
-				Title = "Open or Create Database File",
-				InitialFileName = DatabaseFileInitialName,
-				Filters = DatabaseFileDialogFilter
-			};
-		}
+		return file;
+	}
 
-		public static async Task<IDatabaseFile?> TryOpenOrCreateDatabaseFromPath(string path, Window window, Func<Task<bool>> checkCanUpgradeDatabase) {
-			IDatabaseFile? file = null;
+	public static async Task<DialogResult.YesNo> ShowCanUpgradeDatabaseDialog(Window window) {
+		return await Dialog.ShowYesNo(window, "Database Upgrade", "This database was created with an older version of DHT. If you proceed, the database will be upgraded and will no longer open in previous versions of DHT.\n\nPlease ensure you have a backup of the database. Do you want to proceed with the upgrade?");
+	}
 
-			try {
-				file = await SqliteDatabaseFile.OpenOrCreate(path, checkCanUpgradeDatabase);
-			} catch (InvalidDatabaseVersionException ex) {
-				await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' appears to be corrupted (invalid version: " + ex.Version + ").");
-			} 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);
-				await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' could not be opened:" + ex.Message);
-			}
-
-			return file;
-		}
-
-		public static async Task<DialogResult.YesNo> ShowCanUpgradeDatabaseDialog(Window window) {
-			return await Dialog.ShowYesNo(window, "Database Upgrade", "This database was created with an older version of DHT. If you proceed, the database will be upgraded and will no longer open in previous versions of DHT.\n\nPlease ensure you have a backup of the database. Do you want to proceed with the upgrade?");
-		}
-
-		public static async Task<DialogResult.YesNo> ShowCanUpgradeMultipleDatabaseDialog(Window window) {
-			return await Dialog.ShowYesNo(window, "Database Upgrade", "One or more databases were created with an older version of DHT. If you proceed, these databases will be upgraded and will no longer open in previous versions of DHT. Otherwise, these databases will be skipped.\n\nPlease ensure you have a backup of the databases. Do you want to proceed with the upgrade?");
-		}
+	public static async Task<DialogResult.YesNo> ShowCanUpgradeMultipleDatabaseDialog(Window window) {
+		return await Dialog.ShowYesNo(window, "Database Upgrade", "One or more databases were created with an older version of DHT. If you proceed, these databases will be upgraded and will no longer open in previous versions of DHT. Otherwise, these databases will be skipped.\n\nPlease ensure you have a backup of the databases. Do you want to proceed with the upgrade?");
 	}
 }

app/Desktop/Common/NumberValueConverter.cs

@@ -2,14 +2,14 @@ using System;
 using System.Globalization;
 using Avalonia.Data.Converters;
 
-namespace DHT.Desktop.Common {
-	sealed class NumberValueConverter : IValueConverter {
-		public object Convert(object? value, Type targetType, object? parameter, CultureInfo culture) {
-			return value == null ? "-" : string.Format(Program.Culture, "{0:n0}", value);
-		}
+namespace DHT.Desktop.Common;
 
-		public object ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture) {
-			throw new NotSupportedException();
-		}
+sealed class NumberValueConverter : IValueConverter {
+	public object Convert(object? value, Type targetType, object? parameter, CultureInfo culture) {
+		return value == null ? "-" : string.Format(Program.Culture, "{0:n0}", value);
+	}
+
+	public object ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture) {
+		throw new NotSupportedException();
 	}
 }

app/Desktop/Common/TextFormat.cs

@@ -1,19 +1,19 @@
-namespace DHT.Desktop.Common {
-	static class TextFormat {
-		public static string Format(this int number) {
-			return number.ToString("N0", Program.Culture);
-		}
+namespace DHT.Desktop.Common;
 
-		public static string Format(this long number) {
-			return number.ToString("N0", Program.Culture);
-		}
+static class TextFormat {
+	public static string Format(this int number) {
+		return number.ToString("N0", Program.Culture);
+	}
 
-		public static string Pluralize(this int number, string singular) {
-			return number.Format() + "\u00A0" + (number == 1 ? singular : singular + "s");
-		}
+	public static string Format(this long number) {
+		return number.ToString("N0", Program.Culture);
+	}
 
-		public static string Pluralize(this long number, string singular) {
-			return number.Format() + "\u00A0" + (number == 1 ? singular : singular + "s");
-		}
+	public static string Pluralize(this int number, string singular) {
+		return number.Format() + "\u00A0" + (number == 1 ? singular : singular + "s");
+	}
+
+	public static string Pluralize(this long number, string singular) {
+		return number.Format() + "\u00A0" + (number == 1 ? singular : singular + "s");
 	}
 }

app/Desktop/Desktop.csproj

@@ -1,7 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
-    <TargetFramework>net5.0</TargetFramework>
     <Nullable>enable</Nullable>
     <AssemblyName>DiscordHistoryTracker</AssemblyName>
     <RootNamespace>DHT.Desktop</RootNamespace>
@@ -21,15 +20,23 @@
     <DebugType>none</DebugType>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Avalonia" Version="0.10.13" />
-    <PackageReference Include="Avalonia.Desktop" Version="0.10.13" />
-    <PackageReference Include="Avalonia.Diagnostics" Version="0.10.13" Condition=" '$(Configuration)' == 'Debug' " />
+    <PackageReference Include="Avalonia" Version="11.0.5" />
+    <PackageReference Include="Avalonia.Controls.DataGrid" Version="11.0.5" />
+    <PackageReference Include="Avalonia.Controls.ItemsRepeater" Version="11.0.5" />
+    <PackageReference Include="Avalonia.Desktop" Version="11.0.5" />
+    <PackageReference Include="Avalonia.Diagnostics" Version="11.0.5" Condition=" '$(Configuration)' == 'Debug' " />
+    <PackageReference Include="Avalonia.Fonts.Inter" Version="11.0.5" />
+    <PackageReference Include="Avalonia.Themes.Fluent" Version="11.0.5" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Server\Server.csproj" />
   </ItemGroup>
   <ItemGroup>
     <Compile Include="..\Version.cs" Link="Version.cs" />
+    <Compile Update="Dialogs\TextBox\TextBoxDialog.axaml.cs">
+      <DependentUpon>CheckBoxDialog.axaml</DependentUpon>
+      <SubType>Code</SubType>
+    </Compile>
   </ItemGroup>
   <ItemGroup>
     <AvaloniaResource Include="Resources/icon.ico" />

app/Desktop/Dialogs/CheckBox/CheckBoxDialog.axaml

@@ -34,8 +34,8 @@
 
     <StackPanel Margin="20">
         <ScrollViewer MaxHeight="400">
-            <ItemsControl Items="{Binding Items}">
-                <ItemsControl.ItemTemplate>
+            <ItemsRepeater ItemsSource="{Binding Items}">
+                <ItemsRepeater.ItemTemplate>
                     <DataTemplate>
                         <CheckBox IsChecked="{Binding Checked}">
                             <Label>
@@ -43,8 +43,8 @@
                             </Label>
                         </CheckBox>
                     </DataTemplate>
-                </ItemsControl.ItemTemplate>
-            </ItemsControl>
+                </ItemsRepeater.ItemTemplate>
+            </ItemsRepeater>
         </ScrollViewer>
         <Panel Classes="buttons">
             <WrapPanel Classes="left">

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

@@ -1,31 +1,21 @@
 using System.Diagnostics.CodeAnalysis;
-using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Interactivity;
-using Avalonia.Markup.Xaml;
 using DHT.Desktop.Dialogs.Message;
 
-namespace DHT.Desktop.Dialogs.CheckBox {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class CheckBoxDialog : Window {
-		public CheckBoxDialog() {
-			InitializeComponent();
-			#if DEBUG
-			this.AttachDevTools();
-			#endif
-		}
+namespace DHT.Desktop.Dialogs.CheckBox;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class CheckBoxDialog : Window {
+	public CheckBoxDialog() {
+		InitializeComponent();
+	}
 
-		public void ClickOk(object? sender, RoutedEventArgs e) {
-			Close(DialogResult.OkCancel.Ok);
-		}
+	public void ClickOk(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.OkCancel.Ok);
+	}
 
-		public void ClickCancel(object? sender, RoutedEventArgs e) {
-			Close(DialogResult.OkCancel.Cancel);
-		}
+	public void ClickCancel(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.OkCancel.Cancel);
 	}
 }
-

app/Desktop/Dialogs/CheckBox/CheckBoxDialogModel.cs

@@ -4,67 +4,67 @@ using System.ComponentModel;
 using System.Linq;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Dialogs.CheckBox {
-	class CheckBoxDialogModel : BaseModel {
-		public string Title { get; init; } = "";
+namespace DHT.Desktop.Dialogs.CheckBox;
 
-		private IReadOnlyList<CheckBoxItem> items = Array.Empty<CheckBoxItem>();
+class CheckBoxDialogModel : BaseModel {
+	public string Title { get; init; } = "";
 
-		public IReadOnlyList<CheckBoxItem> Items {
-			get => items;
+	private IReadOnlyList<CheckBoxItem> items = Array.Empty<CheckBoxItem>();
 
-			protected set {
-				foreach (var item in items) {
-					item.PropertyChanged -= OnItemPropertyChanged;
-				}
+	public IReadOnlyList<CheckBoxItem> Items {
+		get => items;
 
-				items = value;
-
-				foreach (var item in items) {
-					item.PropertyChanged += OnItemPropertyChanged;
-				}
-			}
-		}
-
-		private bool pauseCheckEvents = false;
-
-		public bool AreAllSelected => Items.All(static item => item.Checked);
-		public bool AreNoneSelected => Items.All(static item => !item.Checked);
-
-		public void SelectAll() => SetAllChecked(true);
-		public void SelectNone() => SetAllChecked(false);
-
-		private void SetAllChecked(bool isChecked) {
-			pauseCheckEvents = true;
-
-			foreach (var item in Items) {
-				item.Checked = isChecked;
+		protected set {
+			foreach (var item in items) {
+				item.PropertyChanged -= OnItemPropertyChanged;
 			}
 
-			pauseCheckEvents = false;
-			UpdateBulkButtons();
-		}
+			items = value;
 
-		private void UpdateBulkButtons() {
-			OnPropertyChanged(nameof(AreAllSelected));
-			OnPropertyChanged(nameof(AreNoneSelected));
-		}
-
-		private void OnItemPropertyChanged(object? sender, PropertyChangedEventArgs e) {
-			if (!pauseCheckEvents && e.PropertyName == nameof(CheckBoxItem.Checked)) {
-				UpdateBulkButtons();
+			foreach (var item in items) {
+				item.PropertyChanged += OnItemPropertyChanged;
 			}
 		}
 	}
 
-	sealed class CheckBoxDialogModel<T> : CheckBoxDialogModel {
-		public new IReadOnlyList<CheckBoxItem<T>> Items { get; }
+	private bool pauseCheckEvents = false;
 
-		public IEnumerable<CheckBoxItem<T>> SelectedItems => Items.Where(static item => item.Checked);
+	public bool AreAllSelected => Items.All(static item => item.Checked);
+	public bool AreNoneSelected => Items.All(static item => !item.Checked);
 
-		public CheckBoxDialogModel(IEnumerable<CheckBoxItem<T>> items) {
-			this.Items = new List<CheckBoxItem<T>>(items);
-			base.Items = this.Items;
+	public void SelectAll() => SetAllChecked(true);
+	public void SelectNone() => SetAllChecked(false);
+
+	private void SetAllChecked(bool isChecked) {
+		pauseCheckEvents = true;
+
+		foreach (var item in Items) {
+			item.Checked = isChecked;
+		}
+
+		pauseCheckEvents = false;
+		UpdateBulkButtons();
+	}
+
+	private void UpdateBulkButtons() {
+		OnPropertyChanged(nameof(AreAllSelected));
+		OnPropertyChanged(nameof(AreNoneSelected));
+	}
+
+	private void OnItemPropertyChanged(object? sender, PropertyChangedEventArgs e) {
+		if (!pauseCheckEvents && e.PropertyName == nameof(CheckBoxItem.Checked)) {
+			UpdateBulkButtons();
 		}
 	}
 }
+
+sealed class CheckBoxDialogModel<T> : CheckBoxDialogModel {
+	public new IReadOnlyList<CheckBoxItem<T>> Items { get; }
+
+	public IEnumerable<CheckBoxItem<T>> SelectedItems => Items.Where(static item => item.Checked);
+
+	public CheckBoxDialogModel(IEnumerable<CheckBoxItem<T>> items) {
+		this.Items = new List<CheckBoxItem<T>>(items);
+		base.Items = this.Items;
+	}
+}

app/Desktop/Dialogs/CheckBox/CheckBoxItem.cs

@@ -1,24 +1,24 @@
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Dialogs.CheckBox {
-	class CheckBoxItem : BaseModel {
-		public string Title { get; init; } = "";
-		public object? Item { get; init; } = null;
+namespace DHT.Desktop.Dialogs.CheckBox;
 
-		private bool isChecked = false;
+class CheckBoxItem : BaseModel {
+	public string Title { get; init; } = "";
+	public object? Item { get; init; } = null;
 
-		public bool Checked {
-			get => isChecked;
-			set => Change(ref isChecked, value);
-		}
-	}
+	private bool isChecked = false;
 
-	sealed class CheckBoxItem<T> : CheckBoxItem {
-		public new T Item { get; }
-
-		public CheckBoxItem(T item) {
-			this.Item = item;
-			base.Item = item;
-		}
+	public bool Checked {
+		get => isChecked;
+		set => Change(ref isChecked, value);
+	}
+}
+
+sealed class CheckBoxItem<T> : CheckBoxItem {
+	public new T Item { get; }
+
+	public CheckBoxItem(T item) {
+		this.Item = item;
+		base.Item = item;
 	}
 }

app/Desktop/Dialogs/File/FileDialogs.cs

@@ -0,0 +1,36 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using Avalonia.Controls;
+using Avalonia.Platform.Storage;
+
+namespace DHT.Desktop.Dialogs.File;
+
+static class FileDialogs {
+	public static async Task<string[]> OpenFiles(this IStorageProvider storageProvider, FilePickerOpenOptions options) {
+		return (await storageProvider.OpenFilePickerAsync(options)).ToLocalPaths();
+	}
+
+	public static async Task<string?> SaveFile(this IStorageProvider storageProvider, FilePickerSaveOptions options) {
+		return (await storageProvider.SaveFilePickerAsync(options))?.ToLocalPath();
+	}
+
+	public static FilePickerFileType CreateFilter(string name, string[] extensions) {
+		return new FilePickerFileType(name) {
+			Patterns = extensions.Select(static ext => "*." + ext).ToArray()
+		};
+	}
+
+	public static Task<IStorageFolder?> GetSuggestedStartLocation(Window window, string? suggestedDirectory) {
+		return suggestedDirectory == null ? Task.FromResult<IStorageFolder?>(null) : window.StorageProvider.TryGetFolderFromPathAsync(suggestedDirectory);
+	}
+
+	private static string ToLocalPath(this IStorageFile file) {
+		return file.TryGetLocalPath() ?? throw new NotSupportedException("Local filesystem is not supported.");
+	}
+
+	private static string[] ToLocalPaths(this IReadOnlyList<IStorageFile> files) {
+		return files.Select(ToLocalPath).ToArray();
+	}
+}

app/Desktop/Dialogs/Message/Dialog.cs

@@ -2,73 +2,73 @@ using System.Threading.Tasks;
 using Avalonia.Controls;
 using Avalonia.Threading;
 
-namespace DHT.Desktop.Dialogs.Message {
-	static class Dialog {
-		public static async Task ShowOk(Window owner, string title, string message) {
-			if (!Dispatcher.UIThread.CheckAccess()) {
-				await Dispatcher.UIThread.InvokeAsync(() => ShowOk(owner, title, message));
-				return;
-			}
+namespace DHT.Desktop.Dialogs.Message;
 
-			await new MessageDialog {
-				DataContext = new MessageDialogModel {
-					Title = title,
-					Message = message,
-					IsOkVisible = true
-				}
-			}.ShowDialog<DialogResult.All>(owner);
+static class Dialog {
+	public static async Task ShowOk(Window owner, string title, string message) {
+		if (!Dispatcher.UIThread.CheckAccess()) {
+			await Dispatcher.UIThread.InvokeAsync(() => ShowOk(owner, title, message));
+			return;
 		}
 
-		public static async Task<DialogResult.OkCancel> ShowOkCancel(Window owner, string title, string message) {
-			if (!Dispatcher.UIThread.CheckAccess()) {
-				return await Dispatcher.UIThread.InvokeAsync(() => ShowOkCancel(owner, title, message));
+		await new MessageDialog {
+			DataContext = new MessageDialogModel {
+				Title = title,
+				Message = message,
+				IsOkVisible = true
 			}
+		}.ShowDialog<DialogResult.All>(owner);
+	}
 
-			var result = await new MessageDialog {
-				DataContext = new MessageDialogModel {
-					Title = title,
-					Message = message,
-					IsOkVisible = true,
-					IsCancelVisible = true
-				}
-			}.ShowDialog<DialogResult.All?>(owner);
-
-			return result.ToOkCancel();
+	public static async Task<DialogResult.OkCancel> ShowOkCancel(Window owner, string title, string message) {
+		if (!Dispatcher.UIThread.CheckAccess()) {
+			return await Dispatcher.UIThread.InvokeAsync(() => ShowOkCancel(owner, title, message));
 		}
 
-		public static async Task<DialogResult.YesNo> ShowYesNo(Window owner, string title, string message) {
-			if (!Dispatcher.UIThread.CheckAccess()) {
-				return await Dispatcher.UIThread.InvokeAsync(() => ShowYesNo(owner, title, message));
+		var result = await new MessageDialog {
+			DataContext = new MessageDialogModel {
+				Title = title,
+				Message = message,
+				IsOkVisible = true,
+				IsCancelVisible = true
 			}
+		}.ShowDialog<DialogResult.All?>(owner);
 
-			var result = await new MessageDialog {
-				DataContext = new MessageDialogModel {
-					Title = title,
-					Message = message,
-					IsYesVisible = true,
-					IsNoVisible = true
-				}
-			}.ShowDialog<DialogResult.All?>(owner);
+		return result.ToOkCancel();
+	}
 
-			return result.ToYesNo();
+	public static async Task<DialogResult.YesNo> ShowYesNo(Window owner, string title, string message) {
+		if (!Dispatcher.UIThread.CheckAccess()) {
+			return await Dispatcher.UIThread.InvokeAsync(() => ShowYesNo(owner, title, message));
 		}
 
-		public static async Task<DialogResult.YesNoCancel> ShowYesNoCancel(Window owner, string title, string message) {
-			if (!Dispatcher.UIThread.CheckAccess()) {
-				return await Dispatcher.UIThread.InvokeAsync(() => ShowYesNoCancel(owner, title, message));
+		var result = await new MessageDialog {
+			DataContext = new MessageDialogModel {
+				Title = title,
+				Message = message,
+				IsYesVisible = true,
+				IsNoVisible = true
 			}
+		}.ShowDialog<DialogResult.All?>(owner);
 
-			var result = await new MessageDialog {
-				DataContext = new MessageDialogModel {
-					Title = title,
-					Message = message,
-					IsYesVisible = true,
-					IsNoVisible = true,
-					IsCancelVisible = true
-				}
-			}.ShowDialog<DialogResult.All?>(owner);
+		return result.ToYesNo();
+	}
 
-			return result.ToYesNoCancel();
+	public static async Task<DialogResult.YesNoCancel> ShowYesNoCancel(Window owner, string title, string message) {
+		if (!Dispatcher.UIThread.CheckAccess()) {
+			return await Dispatcher.UIThread.InvokeAsync(() => ShowYesNoCancel(owner, title, message));
 		}
+
+		var result = await new MessageDialog {
+			DataContext = new MessageDialogModel {
+				Title = title,
+				Message = message,
+				IsYesVisible = true,
+				IsNoVisible = true,
+				IsCancelVisible = true
+			}
+		}.ShowDialog<DialogResult.All?>(owner);
+
+		return result.ToYesNoCancel();
 	}
 }

app/Desktop/Dialogs/Message/DialogResult.cs

@@ -1,59 +1,59 @@
 using System;
 
-namespace DHT.Desktop.Dialogs.Message {
-	static class DialogResult {
-		public enum All {
-			Ok,
-			Yes,
-			No,
-			Cancel
-		}
+namespace DHT.Desktop.Dialogs.Message;
 
-		public enum OkCancel {
-			Closed,
-			Ok,
-			Cancel
-		}
+static class DialogResult {
+	public enum All {
+		Ok,
+		Yes,
+		No,
+		Cancel
+	}
 
-		public enum YesNo {
-			Closed,
-			Yes,
-			No
-		}
+	public enum OkCancel {
+		Closed,
+		Ok,
+		Cancel
+	}
 
-		public enum YesNoCancel {
-			Closed,
-			Yes,
-			No,
-			Cancel
-		}
+	public enum YesNo {
+		Closed,
+		Yes,
+		No
+	}
 
-		public static OkCancel ToOkCancel(this All? result) {
-			return result switch {
-				null       => OkCancel.Closed,
-				All.Ok     => OkCancel.Ok,
-				All.Cancel => OkCancel.Cancel,
-				_          => throw new ArgumentException("Cannot convert dialog result " + result + " to ok/cancel.")
-			};
-		}
+	public enum YesNoCancel {
+		Closed,
+		Yes,
+		No,
+		Cancel
+	}
 
-		public static YesNo ToYesNo(this All? result) {
-			return result switch {
-				null    => YesNo.Closed,
-				All.Yes => YesNo.Yes,
-				All.No  => YesNo.No,
-				_       => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no.")
-			};
-		}
+	public static OkCancel ToOkCancel(this All? result) {
+		return result switch {
+			null       => OkCancel.Closed,
+			All.Ok     => OkCancel.Ok,
+			All.Cancel => OkCancel.Cancel,
+			_          => throw new ArgumentException("Cannot convert dialog result " + result + " to ok/cancel.")
+		};
+	}
 
-		public static YesNoCancel ToYesNoCancel(this All? result) {
-			return result switch {
-				null       => YesNoCancel.Closed,
-				All.Yes    => YesNoCancel.Yes,
-				All.No     => YesNoCancel.No,
-				All.Cancel => YesNoCancel.Cancel,
-				_          => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no/cancel.")
-			};
-		}
+	public static YesNo ToYesNo(this All? result) {
+		return result switch {
+			null    => YesNo.Closed,
+			All.Yes => YesNo.Yes,
+			All.No  => YesNo.No,
+			_       => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no.")
+		};
+	}
+
+	public static YesNoCancel ToYesNoCancel(this All? result) {
+		return result switch {
+			null       => YesNoCancel.Closed,
+			All.Yes    => YesNoCancel.Yes,
+			All.No     => YesNoCancel.No,
+			All.Cancel => YesNoCancel.Cancel,
+			_          => throw new ArgumentException("Cannot convert dialog result " + result + " to yes/no/cancel.")
+		};
 	}
 }

app/Desktop/Dialogs/Message/MessageDialog.axaml.cs

@@ -1,37 +1,28 @@
 using System.Diagnostics.CodeAnalysis;
-using Avalonia;
 using Avalonia.Controls;
 using Avalonia.Interactivity;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Dialogs.Message {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class MessageDialog : Window {
-		public MessageDialog() {
-			InitializeComponent();
-			#if DEBUG
-			this.AttachDevTools();
-			#endif
-		}
+namespace DHT.Desktop.Dialogs.Message;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class MessageDialog : Window {
+	public MessageDialog() {
+		InitializeComponent();
+	}
 
-		public void ClickOk(object? sender, RoutedEventArgs e) {
-			Close(DialogResult.All.Ok);
-		}
+	public void ClickOk(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.All.Ok);
+	}
 
-		public void ClickYes(object? sender, RoutedEventArgs e) {
-			Close(DialogResult.All.Yes);
-		}
+	public void ClickYes(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.All.Yes);
+	}
 
-		public void ClickNo(object? sender, RoutedEventArgs e) {
-			Close(DialogResult.All.No);
-		}
+	public void ClickNo(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.All.No);
+	}
 
-		public void ClickCancel(object? sender, RoutedEventArgs e) {
-			Close(DialogResult.All.Cancel);
-		}
+	public void ClickCancel(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.All.Cancel);
 	}
 }

app/Desktop/Dialogs/Message/MessageDialogModel.cs

@@ -1,11 +1,11 @@
-namespace DHT.Desktop.Dialogs.Message {
-	sealed class MessageDialogModel {
-		public string Title { get; init; } = "";
-		public string Message { get; init; } = "";
+namespace DHT.Desktop.Dialogs.Message;
 
-		public bool IsOkVisible { get; init; } = false;
-		public bool IsYesVisible { get; init; } = false;
-		public bool IsNoVisible { get; init; } = false;
-		public bool IsCancelVisible { get; init; } = false;
-	}
+sealed class MessageDialogModel {
+	public string Title { get; init; } = "";
+	public string Message { get; init; } = "";
+
+	public bool IsOkVisible { get; init; } = false;
+	public bool IsYesVisible { get; init; } = false;
+	public bool IsNoVisible { get; init; } = false;
+	public bool IsCancelVisible { get; init; } = false;
 }

app/Desktop/Dialogs/Progress/IProgressCallback.cs

@@ -1,7 +1,7 @@
 using System.Threading.Tasks;
 
-namespace DHT.Desktop.Dialogs.Progress {
-	interface IProgressCallback {
-		Task Update(string message, int finishedItems, int totalItems);
-	}
+namespace DHT.Desktop.Dialogs.Progress;
+
+interface IProgressCallback {
+	Task Update(string message, int finishedItems, int totalItems);
 }

app/Desktop/Dialogs/Progress/ProgressDialog.axaml

@@ -7,7 +7,7 @@
         x:Class="DHT.Desktop.Dialogs.Progress.ProgressDialog"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
-        Opened="Loaded"
+        Opened="OnOpened"
         Closing="OnClosing"
         Width="500" SizeToContent="Height" CanResize="False"
         WindowStartupLocation="CenterOwner">

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

@@ -1,40 +1,30 @@
 using System;
-using System.ComponentModel;
 using System.Diagnostics.CodeAnalysis;
 using System.Threading.Tasks;
-using Avalonia;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Dialogs.Progress {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class ProgressDialog : Window {
-		private bool isFinished = false;
+namespace DHT.Desktop.Dialogs.Progress;
 
-		public ProgressDialog() {
-			InitializeComponent();
-			#if DEBUG
-			this.AttachDevTools();
-			#endif
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class ProgressDialog : Window {
+	private bool isFinished = false;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+	public ProgressDialog() {
+		InitializeComponent();
+	}
 
-		public void OnClosing(object? sender, CancelEventArgs e) {
-			e.Cancel = !isFinished;
-		}
-
-		public void Loaded(object? sender, EventArgs e) {
-			if (DataContext is ProgressDialogModel model) {
-				Task.Run(model.StartTask).ContinueWith(OnFinished, TaskScheduler.FromCurrentSynchronizationContext());
-			}
-		}
-
-		private void OnFinished(Task task) {
-			isFinished = true;
-			Close();
+	public void OnOpened(object? sender, EventArgs e) {
+		if (DataContext is ProgressDialogModel model) {
+			Task.Run(model.StartTask).ContinueWith(OnFinished, TaskScheduler.FromCurrentSynchronizationContext());
 		}
 	}
+
+	public void OnClosing(object? sender, WindowClosingEventArgs e) {
+		e.Cancel = !isFinished;
+	}
+
+	private void OnFinished(Task task) {
+		isFinished = true;
+		Close();
+	}
 }

app/Desktop/Dialogs/Progress/ProgressDialogModel.cs

@@ -4,62 +4,62 @@ using Avalonia.Threading;
 using DHT.Desktop.Common;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Dialogs.Progress {
-	sealed class ProgressDialogModel : BaseModel {
-		public string Title { get; init; } = "";
+namespace DHT.Desktop.Dialogs.Progress;
 
-		private string message = "";
+sealed class ProgressDialogModel : BaseModel {
+	public string Title { get; init; } = "";
 
-		public string Message {
-			get => message;
-			private set => Change(ref message, value);
+	private string message = "";
+
+	public string Message {
+		get => message;
+		private set => Change(ref message, value);
+	}
+
+	private string items = "";
+
+	public string Items {
+		get => items;
+		private set => Change(ref items, value);
+	}
+
+	private int progress = 0;
+
+	public int Progress {
+		get => progress;
+		private set => Change(ref progress, value);
+	}
+
+	private readonly TaskRunner? task;
+
+	[Obsolete("Designer")]
+	public ProgressDialogModel() {}
+
+	public ProgressDialogModel(TaskRunner task) {
+		this.task = task;
+	}
+
+	internal async Task StartTask() {
+		if (task != null) {
+			await task(new Callback(this));
+		}
+	}
+
+	public delegate Task TaskRunner(IProgressCallback callback);
+
+	private sealed class Callback : IProgressCallback {
+		private readonly ProgressDialogModel model;
+
+		public Callback(ProgressDialogModel model) {
+			this.model = model;
 		}
 
-		private string items = "";
-
-		public string Items {
-			get => items;
-			private set => Change(ref items, value);
-		}
-
-		private int progress = 0;
-
-		public int Progress {
-			get => progress;
-			private set => Change(ref progress, value);
-		}
-
-		private readonly TaskRunner? task;
-
-		[Obsolete("Designer")]
-		public ProgressDialogModel() {}
-
-		public ProgressDialogModel(TaskRunner task) {
-			this.task = task;
-		}
-
-		internal async Task StartTask() {
-			if (task != null) {
-				await task(new Callback(this));
-			}
-		}
-
-		public delegate Task TaskRunner(IProgressCallback callback);
-
-		private sealed class Callback : IProgressCallback {
-			private readonly ProgressDialogModel model;
-
-			public Callback(ProgressDialogModel model) {
-				this.model = model;
-			}
-
-			async Task IProgressCallback.Update(string message, int finishedItems, int totalItems) {
-				await Dispatcher.UIThread.InvokeAsync(() => {
-					model.Message = message;
-					model.Items = finishedItems.Format() + " / " + totalItems.Format();
-					model.Progress = 100 * finishedItems / totalItems;
-				});
-			}
+		async Task IProgressCallback.Update(string message, int finishedItems, int totalItems) {
+			await Dispatcher.UIThread.InvokeAsync(() => {
+				model.Message = message;
+				model.Items = finishedItems.Format() + " / " + totalItems.Format();
+				model.Progress = 100 * finishedItems / totalItems;
+			});
 		}
 	}
 }

app/Desktop/Dialogs/TextBox/TextBoxDialog.axaml

@@ -0,0 +1,56 @@
+<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.Dialogs.TextBox"
+        mc:Ignorable="d" d:DesignWidth="500"
+        x:Class="DHT.Desktop.Dialogs.TextBox.TextBoxDialog"
+        Title="{Binding Title}"
+        Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
+        Width="500" SizeToContent="Height" CanResize="False"
+        WindowStartupLocation="CenterOwner">
+
+    <Window.DataContext>
+        <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">
+                <TextBlock Text="{Binding Description}" TextWrapping="Wrap" />
+                <ItemsRepeater ItemsSource="{Binding Items}">
+                    <ItemsRepeater.ItemTemplate>
+                        <DataTemplate>
+                            <DockPanel Margin="0 5 25 0">
+                                <TextBox Name="Input" Text="{Binding Value}" Width="180" VerticalAlignment="Top" DockPanel.Dock="Right" />
+                                <Label Target="Input" VerticalAlignment="Center" DockPanel.Dock="Left">
+                                    <TextBlock Text="{Binding Title}" TextWrapping="Wrap" />
+                                </Label>
+                            </DockPanel>
+                        </DataTemplate>
+                    </ItemsRepeater.ItemTemplate>
+                </ItemsRepeater>
+            </StackPanel>
+        </ScrollViewer>
+        <Panel Classes="buttons">
+            <WrapPanel Classes="right">
+                <Button Click="ClickOk" IsEnabled="{Binding !HasErrors}">OK</Button>
+                <Button Click="ClickCancel">Cancel</Button>
+            </WrapPanel>
+        </Panel>
+    </StackPanel>
+
+</Window>

app/Desktop/Dialogs/TextBox/TextBoxDialog.axaml.cs

@@ -0,0 +1,21 @@
+using System.Diagnostics.CodeAnalysis;
+using Avalonia.Controls;
+using Avalonia.Interactivity;
+using DHT.Desktop.Dialogs.Message;
+
+namespace DHT.Desktop.Dialogs.TextBox; 
+
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class TextBoxDialog : Window {
+	public TextBoxDialog() {
+		InitializeComponent();
+	}
+
+	public void ClickOk(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.OkCancel.Ok);
+	}
+
+	public void ClickCancel(object? sender, RoutedEventArgs e) {
+		Close(DialogResult.OkCancel.Cancel);
+	}
+}

app/Desktop/Dialogs/TextBox/TextBoxDialogModel.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using DHT.Utils.Models;
+
+namespace DHT.Desktop.Dialogs.TextBox; 
+
+class TextBoxDialogModel : BaseModel {
+	public string Title { get; init; } = "";
+	public string Description { get; init; } = "";
+
+	private IReadOnlyList<TextBoxItem> items = Array.Empty<TextBoxItem>();
+
+	public IReadOnlyList<TextBoxItem> Items {
+		get => items;
+
+		protected set {
+			foreach (var item in items) {
+				item.ErrorsChanged -= OnItemErrorsChanged;
+			}
+
+			items = value;
+
+			foreach (var item in items) {
+				item.ErrorsChanged += OnItemErrorsChanged;
+			}
+		}
+	}
+		
+	public bool HasErrors => Items.Any(static item => !item.IsValid);
+
+	private void OnItemErrorsChanged(object? sender, DataErrorsChangedEventArgs e) {
+		OnPropertyChanged(nameof(HasErrors));
+	}
+}
+
+sealed class TextBoxDialogModel<T> : TextBoxDialogModel {
+	public new IReadOnlyList<TextBoxItem<T>> Items { get; }
+
+	public IEnumerable<TextBoxItem<T>> ValidItems => Items.Where(static item => item.IsValid);
+
+	public TextBoxDialogModel(IEnumerable<TextBoxItem<T>> items) {
+		this.Items = new List<TextBoxItem<T>>(items);
+		base.Items = this.Items;
+	}
+}

app/Desktop/Dialogs/TextBox/TextBoxItem.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Collections;
+using System.ComponentModel;
+using DHT.Utils.Models;
+
+namespace DHT.Desktop.Dialogs.TextBox; 
+
+class TextBoxItem : BaseModel, 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);
+
+	private string value = string.Empty;
+
+	public string Value {
+		get => this.value;
+		set {
+			Change(ref this.value, value);
+			ErrorsChanged?.Invoke(this, new DataErrorsChangedEventArgs(nameof(Value)));
+		}
+	}
+
+	public IEnumerable GetErrors(string? propertyName) {
+		if (propertyName == nameof(Value) && !IsValid) {
+			yield return string.Empty;
+		}
+	}
+
+	public bool HasErrors => !IsValid;
+	public event EventHandler<DataErrorsChangedEventArgs>? ErrorsChanged;
+}
+
+sealed class TextBoxItem<T> : TextBoxItem {
+	public new T Item { get; }
+
+	public TextBoxItem(T item) {
+		this.Item = item;
+		base.Item = item;
+	}
+}

app/Desktop/Discord/DiscordAppSettings.cs

@@ -9,111 +9,113 @@ using DHT.Utils.Logging;
 using static System.Environment.SpecialFolder;
 using static System.Environment.SpecialFolderOption;
 
-namespace DHT.Desktop.Discord {
-	static class DiscordAppSettings {
-		private static readonly Log Log = Log.ForType(typeof(DiscordAppSettings));
+namespace DHT.Desktop.Discord;
 
-		private const string JsonKeyDevTools = "DANGEROUS_ENABLE_DEVTOOLS_ONLY_ENABLE_IF_YOU_KNOW_WHAT_YOURE_DOING";
+static class DiscordAppSettings {
+	private static readonly Log Log = Log.ForType(typeof(DiscordAppSettings));
 
-		public static string JsonFilePath { get; }
-		private static string JsonBackupFilePath { get; }
+	private const string JsonKeyDevTools = "DANGEROUS_ENABLE_DEVTOOLS_ONLY_ENABLE_IF_YOU_KNOW_WHAT_YOURE_DOING";
 
-		[SuppressMessage("ReSharper", "ConvertIfStatementToConditionalTernaryExpression")]
-		static DiscordAppSettings() {
-			string rootFolder;
+	public static string JsonFilePath { get; }
+	private static string JsonBackupFilePath { get; }
 
-			if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
-				rootFolder = Path.Combine(Environment.GetFolderPath(ApplicationData, DoNotVerify), "Discord");
-			}
-			else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX)) {
-				rootFolder = Path.Combine(Environment.GetFolderPath(UserProfile, DoNotVerify), "Library", "Application Support", "Discord");
-			}
-			else {
-				rootFolder = Path.Combine(Environment.GetFolderPath(ApplicationData, DoNotVerify), "discord");
-			}
+	[SuppressMessage("ReSharper", "ConvertIfStatementToConditionalTernaryExpression")]
+	static DiscordAppSettings() {
+		string rootFolder;
 
-			JsonFilePath = Path.Combine(rootFolder, "settings.json");
-			JsonBackupFilePath = JsonFilePath + ".bak";
+		if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
+			rootFolder = Path.Combine(Environment.GetFolderPath(ApplicationData, DoNotVerify), "Discord");
+		}
+		else if (RuntimeInformation.IsOSPlatform(OSPlatform.OSX)) {
+			rootFolder = Path.Combine(Environment.GetFolderPath(UserProfile, DoNotVerify), "Library", "Application Support", "Discord");
+		}
+		else {
+			rootFolder = Path.Combine(Environment.GetFolderPath(ApplicationData, DoNotVerify), "discord");
 		}
 
-		public static async Task<bool?> AreDevToolsEnabled() {
-			try {
-				return AreDevToolsEnabled(await ReadSettingsJson());
-			} catch (Exception) {
-				return null;
-			}
-		}
+		JsonFilePath = Path.Combine(rootFolder, "settings.json");
+		JsonBackupFilePath = JsonFilePath + ".bak";
+	}
 
-		private static bool AreDevToolsEnabled(Dictionary<string, object?> json) {
-			return json.TryGetValue(JsonKeyDevTools, out var value) && value is JsonElement { ValueKind: JsonValueKind.True };
-		}
-
-		public static async Task<SettingsJsonResult> ConfigureDevTools(bool enable) {
-			Dictionary<string, object?> json;
-
-			try {
-				json = await ReadSettingsJson();
-			} catch (FileNotFoundException) {
-				return SettingsJsonResult.FileNotFound;
-			} catch (JsonException) {
-				return SettingsJsonResult.InvalidJson;
-			} catch (Exception e) {
-				Log.Error(e);
-				return SettingsJsonResult.ReadError;
-			}
-
-			if (enable == AreDevToolsEnabled(json)) {
-				return SettingsJsonResult.AlreadySet;
-			}
-
-			if (enable) {
-				json[JsonKeyDevTools] = true;
-			}
-			else {
-				json.Remove(JsonKeyDevTools);
-			}
-
-			try {
-				if (!File.Exists(JsonBackupFilePath)) {
-					File.Copy(JsonFilePath, JsonBackupFilePath);
-				}
-
-				await WriteSettingsJson(json);
-			} catch (Exception e) {
-				Log.Error("An error occurred when writing settings file.");
-				Log.Error(e);
-
-				if (File.Exists(JsonBackupFilePath)) {
-					try {
-						File.Move(JsonBackupFilePath, JsonFilePath, true);
-						Log.Info("Restored settings file from backup.");
-					} catch (Exception e2) {
-						Log.Error("Cannot restore settings file from backup.");
-						Log.Error(e2);
-					}
-				}
-
-				return SettingsJsonResult.WriteError;
-			}
-
-			try {
-				File.Delete(JsonBackupFilePath);
-			} catch (Exception e) {
-				Log.Error("Cannot delete backup file.");
-				Log.Error(e);
-			}
-
-			return SettingsJsonResult.Success;
-		}
-
-		private static async Task<Dictionary<string, object?>> ReadSettingsJson() {
-			await using var stream = new FileStream(JsonFilePath, FileMode.Open, FileAccess.Read, FileShare.Read);
-			return await JsonSerializer.DeserializeAsync<Dictionary<string, object?>?>(stream) ?? throw new JsonException();
-		}
-
-		private static async Task WriteSettingsJson(Dictionary<string, object?> json) {
-			await using var stream = new FileStream(JsonFilePath, FileMode.Truncate, FileAccess.Write, FileShare.None);
-			await JsonSerializer.SerializeAsync(stream, json, new JsonSerializerOptions { WriteIndented = true });
+	public static async Task<bool?> AreDevToolsEnabled() {
+		try {
+			return AreDevToolsEnabled(await ReadSettingsJson());
+		} catch (Exception e) {
+			Log.Error("Cannot read settings file.");
+			Log.Error(e);
+			return null;
 		}
 	}
+
+	private static bool AreDevToolsEnabled(Dictionary<string, object?> json) {
+		return json.TryGetValue(JsonKeyDevTools, out var value) && value is JsonElement { ValueKind: JsonValueKind.True };
+	}
+
+	public static async Task<SettingsJsonResult> ConfigureDevTools(bool enable) {
+		Dictionary<string, object?> json;
+
+		try {
+			json = await ReadSettingsJson();
+		} catch (FileNotFoundException) {
+			return SettingsJsonResult.FileNotFound;
+		} catch (JsonException) {
+			return SettingsJsonResult.InvalidJson;
+		} catch (Exception e) {
+			Log.Error(e);
+			return SettingsJsonResult.ReadError;
+		}
+
+		if (enable == AreDevToolsEnabled(json)) {
+			return SettingsJsonResult.AlreadySet;
+		}
+
+		if (enable) {
+			json[JsonKeyDevTools] = true;
+		}
+		else {
+			json.Remove(JsonKeyDevTools);
+		}
+
+		try {
+			if (!File.Exists(JsonBackupFilePath)) {
+				File.Copy(JsonFilePath, JsonBackupFilePath);
+			}
+
+			await WriteSettingsJson(json);
+		} catch (Exception e) {
+			Log.Error("An error occurred when writing settings file.");
+			Log.Error(e);
+
+			if (File.Exists(JsonBackupFilePath)) {
+				try {
+					File.Move(JsonBackupFilePath, JsonFilePath, true);
+					Log.Info("Restored settings file from backup.");
+				} catch (Exception e2) {
+					Log.Error("Cannot restore settings file from backup.");
+					Log.Error(e2);
+				}
+			}
+
+			return SettingsJsonResult.WriteError;
+		}
+
+		try {
+			File.Delete(JsonBackupFilePath);
+		} catch (Exception e) {
+			Log.Error("Cannot delete backup file.");
+			Log.Error(e);
+		}
+
+		return SettingsJsonResult.Success;
+	}
+
+	private static async Task<Dictionary<string, object?>> ReadSettingsJson() {
+		await using var stream = new FileStream(JsonFilePath, FileMode.Open, FileAccess.Read, FileShare.Read);
+		return await JsonSerializer.DeserializeAsync<Dictionary<string, object?>?>(stream) ?? throw new JsonException();
+	}
+
+	private static async Task WriteSettingsJson(Dictionary<string, object?> json) {
+		await using var stream = new FileStream(JsonFilePath, FileMode.Truncate, FileAccess.Write, FileShare.None);
+		await JsonSerializer.SerializeAsync(stream, json, new JsonSerializerOptions { WriteIndented = true });
+	}
 }

app/Desktop/Discord/SettingsJsonResult.cs

@@ -1,10 +1,10 @@
-namespace DHT.Desktop.Discord {
-	enum SettingsJsonResult {
-		Success,
-		AlreadySet,
-		FileNotFound,
-		ReadError,
-		InvalidJson,
-		WriteError
-	}
+namespace DHT.Desktop.Discord;
+
+enum SettingsJsonResult {
+	Success,
+	AlreadySet,
+	FileNotFound,
+	ReadError,
+	InvalidJson,
+	WriteError
 }

app/Desktop/Main/AboutWindow.axaml

@@ -46,7 +46,7 @@
             <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 5</TextBlock>
+            <TextBlock Grid.Row="2" Grid.Column="0">.NET 8</TextBlock>
             <TextBlock Grid.Row="2" Grid.Column="1">MIT</TextBlock>
             <Button Grid.Row="2" Grid.Column="2" Command="{Binding ShowLibraryNetCore}">GitHub</Button>
 

app/Desktop/Main/AboutWindow.axaml.cs

@@ -1,20 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
-using Avalonia;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class AboutWindow : Window {
-		public AboutWindow() {
-			InitializeComponent();
-			#if DEBUG
-			this.AttachDevTools();
-			#endif
-		}
+namespace DHT.Desktop.Main;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class AboutWindow : Window {
+	public AboutWindow() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/AboutWindowModel.cs

@@ -1,33 +1,33 @@
 using System.Diagnostics;
 
-namespace DHT.Desktop.Main {
-	sealed class AboutWindowModel {
-		public void ShowOfficialWebsite() {
-			OpenUrl("https://dht.chylex.com");
-		}
+namespace DHT.Desktop.Main;
 
-		public void ShowSourceCode() {
-			OpenUrl("https://github.com/chylex/Discord-History-Tracker");
-		}
+sealed class AboutWindowModel {
+	public void ShowOfficialWebsite() {
+		OpenUrl("https://dht.chylex.com");
+	}
 
-		public void ShowLibraryAvalonia() {
-			OpenUrl("https://www.nuget.org/packages/Avalonia");
-		}
+	public void ShowSourceCode() {
+		OpenUrl("https://github.com/chylex/Discord-History-Tracker");
+	}
 
-		public void ShowLibrarySqlite() {
-			OpenUrl("https://www.sqlite.org");
-		}
+	public void ShowLibraryAvalonia() {
+		OpenUrl("https://www.nuget.org/packages/Avalonia");
+	}
 
-		public void ShowLibrarySqliteAdoNet() {
-			OpenUrl("https://www.nuget.org/packages/Microsoft.Data.Sqlite");
-		}
+	public void ShowLibrarySqlite() {
+		OpenUrl("https://www.sqlite.org");
+	}
 
-		public void ShowLibraryNetCore() {
-			OpenUrl("https://github.com/dotnet/core");
-		}
+	public void ShowLibrarySqliteAdoNet() {
+		OpenUrl("https://www.nuget.org/packages/Microsoft.Data.Sqlite");
+	}
 
-		private static void OpenUrl(string url) {
-			Process.Start(new ProcessStartInfo { FileName = url, UseShellExecute = true });
-		}
+	public void ShowLibraryNetCore() {
+		OpenUrl("https://github.com/dotnet/core");
+	}
+
+	private static void OpenUrl(string url) {
+		Process.Start(new ProcessStartInfo { FileName = url, UseShellExecute = true });
 	}
 }

app/Desktop/Main/Controls/AttachmentFilterPanel.axaml

@@ -0,0 +1,51 @@
+<UserControl 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:controls="clr-namespace:DHT.Desktop.Main.Controls"
+             mc:Ignorable="d"
+             x:Class="DHT.Desktop.Main.Controls.AttachmentFilterPanel">
+
+    <Design.DataContext>
+        <controls:AttachmentFilterPanelModel />
+    </Design.DataContext>
+
+    <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>
+        <Style Selector="ComboBox">
+            <Setter Property="Margin" Value="8 0 0 0" />
+        </Style>
+        <Style Selector="Button">
+            <Setter Property="Margin" Value="0 0 0 8" />
+        </Style>
+    </UserControl.Styles>
+
+    <StackPanel>
+        <TextBlock Text="{Binding FilterStatisticsText}" />
+        <WrapPanel>
+            <StackPanel>
+                <CheckBox IsChecked="{Binding LimitSize}">Limit Size</CheckBox>
+                <StackPanel Orientation="Horizontal">
+                    <TextBox Text="{Binding MaximumSize}" IsEnabled="{Binding LimitSize}" HorizontalContentAlignment="Right" />
+                    <ComboBox IsEnabled="{Binding LimitSize}" ItemsSource="{Binding Units}" SelectedItem="{Binding MaximumSizeUnit}">
+                        <ComboBox.ItemTemplate>
+                            <DataTemplate>
+                                <TextBlock Text="{Binding Name}" />
+                            </DataTemplate>
+                        </ComboBox.ItemTemplate>
+                    </ComboBox>
+                </StackPanel>
+            </StackPanel>
+        </WrapPanel>
+    </StackPanel>
+
+</UserControl>

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

@@ -0,0 +1,11 @@
+using System.Diagnostics.CodeAnalysis;
+using Avalonia.Controls;
+
+namespace DHT.Desktop.Main.Controls;
+
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class AttachmentFilterPanel : UserControl {
+	public AttachmentFilterPanel() {
+		InitializeComponent();
+	}
+}

app/Desktop/Main/Controls/AttachmentFilterPanelModel.cs

@@ -0,0 +1,129 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using DHT.Desktop.Common;
+using DHT.Server.Data.Filters;
+using DHT.Server.Database;
+using DHT.Utils.Models;
+using DHT.Utils.Tasks;
+
+namespace DHT.Desktop.Main.Controls;
+
+sealed class AttachmentFilterPanelModel : BaseModel, IDisposable {
+	public sealed record Unit(string Name, uint Scale);
+
+	private static readonly Unit[] AllUnits = {
+		new ("B", 1),
+		new ("kB", 1024),
+		new ("MB", 1024 * 1024)
+	};
+
+	private static readonly HashSet<string> FilterProperties = new () {
+		nameof(LimitSize),
+		nameof(MaximumSize),
+		nameof(MaximumSizeUnit)
+	};
+
+	public string FilterStatisticsText { get; private set; } = "";
+
+	private bool limitSize = false;
+	private ulong maximumSize = 0L;
+	private Unit maximumSizeUnit = AllUnits[0];
+
+	public bool LimitSize {
+		get => limitSize;
+		set => Change(ref limitSize, value);
+	}
+
+	public ulong MaximumSize {
+		get => maximumSize;
+		set => Change(ref maximumSize, value);
+	}
+
+	public Unit MaximumSizeUnit {
+		get => maximumSizeUnit;
+		set => Change(ref maximumSizeUnit, value);
+	}
+
+	public IEnumerable<Unit> Units => AllUnits;
+
+	private readonly IDatabaseFile db;
+	private readonly string verb;
+
+	private readonly AsyncValueComputer<long> matchingAttachmentCountComputer;
+	private long? matchingAttachmentCount;
+	private long? totalAttachmentCount;
+
+	[Obsolete("Designer")]
+	public AttachmentFilterPanelModel() : this(DummyDatabaseFile.Instance) {}
+
+	public AttachmentFilterPanelModel(IDatabaseFile db, string verb = "Matches") {
+		this.db = db;
+		this.verb = verb;
+
+		this.matchingAttachmentCountComputer = AsyncValueComputer<long>.WithResultProcessor(SetAttachmentCounts).Build();
+
+		UpdateFilterStatistics();
+
+		PropertyChanged += OnPropertyChanged;
+		db.Statistics.PropertyChanged += OnDbStatisticsChanged;
+	}
+
+	public void Dispose() {
+		db.Statistics.PropertyChanged -= OnDbStatisticsChanged;
+	}
+
+	private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName != null && FilterProperties.Contains(e.PropertyName)) {
+			UpdateFilterStatistics();
+		}
+	}
+
+	private void OnDbStatisticsChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName == nameof(DatabaseStatistics.TotalAttachments)) {
+			totalAttachmentCount = db.Statistics.TotalAttachments;
+			UpdateFilterStatistics();
+		}
+	}
+
+	private void UpdateFilterStatistics() {
+		var filter = CreateFilter();
+		if (filter.IsEmpty) {
+			matchingAttachmentCountComputer.Cancel();
+			matchingAttachmentCount = totalAttachmentCount;
+			UpdateFilterStatisticsText();
+		}
+		else {
+			matchingAttachmentCount = null;
+			UpdateFilterStatisticsText();
+			matchingAttachmentCountComputer.Compute(() => db.CountAttachments(filter));
+		}
+	}
+
+	private void SetAttachmentCounts(long matchingAttachmentCount) {
+		this.matchingAttachmentCount = matchingAttachmentCount;
+		UpdateFilterStatisticsText();
+	}
+
+	private void UpdateFilterStatisticsText() {
+		var matchingAttachmentCountStr = matchingAttachmentCount?.Format() ?? "(...)";
+		var totalAttachmentCountStr = totalAttachmentCount?.Format() ?? "(...)";
+
+		FilterStatisticsText = verb + " " + matchingAttachmentCountStr + " out of " + totalAttachmentCountStr + " attachment" + (totalAttachmentCount is null or 1 ? "." : "s.");
+		OnPropertyChanged(nameof(FilterStatisticsText));
+	}
+
+	public AttachmentFilter CreateFilter() {
+		AttachmentFilter filter = new();
+
+		if (LimitSize) {
+			try {
+				filter.MaxBytes = maximumSize * maximumSizeUnit.Scale;
+			} catch (ArithmeticException) {
+				// set no size limit, because the overflown size is larger than any file could possibly be
+			}
+		}
+
+		return filter;
+	}
+}

app/Desktop/Main/Controls/FilterPanel.axaml

@@ -1,60 +0,0 @@
-<UserControl 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:controls="clr-namespace:DHT.Desktop.Main.Controls"
-             mc:Ignorable="d"
-             x:Class="DHT.Desktop.Main.Controls.FilterPanel">
-
-    <Design.DataContext>
-        <controls:FilterPanelModel />
-    </Design.DataContext>
-
-    <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>
-        <Style Selector="Grid > CalendarDatePicker">
-            <Setter Property="CornerRadius" Value="0" />
-            <Setter Property="HorizontalAlignment" Value="Stretch" />
-            <Setter Property="HorizontalContentAlignment" Value="Center" />
-            <Setter Property="VerticalAlignment" Value="Center" />
-            <Setter Property="VerticalContentAlignment" Value="Center" />
-            <Setter Property="IsTodayHighlighted" Value="True" />
-            <Setter Property="SelectedDateFormat" Value="Short" />
-        </Style>
-        <Style Selector="Button">
-            <Setter Property="Margin" Value="0 0 0 8" />
-        </Style>
-    </UserControl.Styles>
-
-    <WrapPanel>
-        <StackPanel>
-            <CheckBox IsChecked="{Binding FilterByDate}">Filter by Date</CheckBox>
-            <Grid ColumnDefinitions="Auto, 4, 125" RowDefinitions="Auto, 4, Auto" Margin="4 0">
-                <Label Grid.Row="0" Grid.Column="0">From:</Label>
-                <CalendarDatePicker Grid.Row="0" Grid.Column="2" x:Name="StartDatePicker" IsEnabled="{Binding FilterByDate}" SelectedDateChanged="CalendarDatePicker_OnSelectedDateChanged" />
-                <Label Grid.Row="2" Grid.Column="0">To:</Label>
-                <CalendarDatePicker Grid.Row="2" Grid.Column="2" x:Name="EndDatePicker" IsEnabled="{Binding FilterByDate}" SelectedDateChanged="CalendarDatePicker_OnSelectedDateChanged" />
-            </Grid>
-        </StackPanel>
-        <StackPanel>
-            <CheckBox IsChecked="{Binding FilterByChannel}">Filter by Channel</CheckBox>
-            <Button Command="{Binding OpenChannelFilterDialog}" IsEnabled="{Binding FilterByChannel}">Select Channels...</Button>
-            <TextBlock Text="{Binding ChannelFilterLabel}" />
-        </StackPanel>
-        <StackPanel>
-            <CheckBox IsChecked="{Binding FilterByUser}">Filter by User</CheckBox>
-            <Button Command="{Binding OpenUserFilterDialog}" IsEnabled="{Binding FilterByUser}">Select Users...</Button>
-            <TextBlock Text="{Binding UserFilterLabel}" />
-        </StackPanel>
-    </WrapPanel>
-
-</UserControl>

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

@@ -1,34 +0,0 @@
-using System.Diagnostics.CodeAnalysis;
-using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
-
-namespace DHT.Desktop.Main.Controls {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class FilterPanel : UserControl {
-		private CalendarDatePicker StartDatePicker => this.FindControl<CalendarDatePicker>("StartDatePicker");
-		private CalendarDatePicker EndDatePicker => this.FindControl<CalendarDatePicker>("EndDatePicker");
-
-		public FilterPanel() {
-			InitializeComponent();
-		}
-
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-
-			var culture = Program.Culture;
-			foreach (var picker in new CalendarDatePicker[] { StartDatePicker, EndDatePicker }) {
-				picker.FirstDayOfWeek = culture.DateTimeFormat.FirstDayOfWeek;
-				picker.SelectedDateFormat = CalendarDatePickerFormat.Custom;
-				picker.CustomDateFormatString = culture.DateTimeFormat.ShortDatePattern;
-				picker.Watermark = culture.DateTimeFormat.ShortDatePattern;
-			}
-		}
-
-		public void CalendarDatePicker_OnSelectedDateChanged(object? sender, SelectionChangedEventArgs e) {
-			if (DataContext is FilterPanelModel model) {
-				model.StartDate = StartDatePicker.SelectedDate;
-				model.EndDate = EndDatePicker.SelectedDate;
-			}
-		}
-	}
-}

app/Desktop/Main/Controls/FilterPanelModel.cs

@@ -1,241 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.ComponentModel;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-using Avalonia.Controls;
-using DHT.Desktop.Common;
-using DHT.Desktop.Dialogs.CheckBox;
-using DHT.Desktop.Dialogs.Message;
-using DHT.Server.Data;
-using DHT.Server.Data.Filters;
-using DHT.Server.Database;
-using DHT.Utils.Models;
-
-namespace DHT.Desktop.Main.Controls {
-	sealed class FilterPanelModel : BaseModel, IDisposable {
-		private static readonly HashSet<string> FilterProperties = new () {
-			nameof(FilterByDate),
-			nameof(StartDate),
-			nameof(EndDate),
-			nameof(FilterByChannel),
-			nameof(IncludedChannels),
-			nameof(FilterByUser),
-			nameof(IncludedUsers)
-		};
-
-		public event PropertyChangedEventHandler? FilterPropertyChanged;
-
-		public bool HasAnyFilters => FilterByDate || FilterByChannel || FilterByUser;
-
-		private bool filterByDate = false;
-		private DateTime? startDate = null;
-		private DateTime? endDate = null;
-		private bool filterByChannel = false;
-		private HashSet<ulong>? includedChannels = null;
-		private bool filterByUser = false;
-		private HashSet<ulong>? includedUsers = null;
-
-		public bool FilterByDate {
-			get => filterByDate;
-			set => Change(ref filterByDate, value);
-		}
-
-		public DateTime? StartDate {
-			get => startDate;
-			set => Change(ref startDate, value);
-		}
-
-		public DateTime? EndDate {
-			get => endDate;
-			set => Change(ref endDate, value);
-		}
-
-		public bool FilterByChannel {
-			get => filterByChannel;
-			set => Change(ref filterByChannel, value);
-		}
-
-		public HashSet<ulong> IncludedChannels {
-			get => includedChannels ?? db.GetAllChannels().Select(static channel => channel.Id).ToHashSet();
-			set => Change(ref includedChannels, value);
-		}
-
-		public bool FilterByUser {
-			get => filterByUser;
-			set => Change(ref filterByUser, value);
-		}
-
-		public HashSet<ulong> IncludedUsers {
-			get => includedUsers ?? db.GetAllUsers().Select(static user => user.Id).ToHashSet();
-			set => Change(ref includedUsers, value);
-		}
-
-		private string channelFilterLabel = "";
-
-		public string ChannelFilterLabel {
-			get => channelFilterLabel;
-			set => Change(ref channelFilterLabel, value);
-		}
-
-		private string userFilterLabel = "";
-
-		public string UserFilterLabel {
-			get => userFilterLabel;
-			set => Change(ref userFilterLabel, value);
-		}
-
-		private readonly Window window;
-		private readonly IDatabaseFile db;
-
-		[Obsolete("Designer")]
-		public FilterPanelModel() : this(null!, DummyDatabaseFile.Instance) {}
-
-		public FilterPanelModel(Window window, IDatabaseFile db) {
-			this.window = window;
-			this.db = db;
-
-			UpdateChannelFilterLabel();
-			UpdateUserFilterLabel();
-
-			PropertyChanged += OnPropertyChanged;
-			db.Statistics.PropertyChanged += OnDbStatisticsChanged;
-		}
-
-		public void Dispose() {
-			db.Statistics.PropertyChanged -= OnDbStatisticsChanged;
-		}
-
-		private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
-			if (e.PropertyName != null && FilterProperties.Contains(e.PropertyName)) {
-				FilterPropertyChanged?.Invoke(sender, e);
-			}
-
-			if (e.PropertyName is nameof(FilterByChannel) or nameof(IncludedChannels)) {
-				UpdateChannelFilterLabel();
-			}
-			else if (e.PropertyName is nameof(FilterByUser) or nameof(IncludedUsers)) {
-				UpdateUserFilterLabel();
-			}
-		}
-
-		private void OnDbStatisticsChanged(object? sender, PropertyChangedEventArgs e) {
-			if (e.PropertyName == nameof(DatabaseStatistics.TotalChannels)) {
-				UpdateChannelFilterLabel();
-			}
-			else if (e.PropertyName == nameof(DatabaseStatistics.TotalUsers)) {
-				UpdateUserFilterLabel();
-			}
-		}
-
-		public async void OpenChannelFilterDialog() {
-			var servers = db.GetAllServers().ToDictionary(static server => server.Id);
-			var items = new List<CheckBoxItem<ulong>>();
-			var included = IncludedChannels;
-
-			foreach (var channel in db.GetAllChannels()) {
-				var channelId = channel.Id;
-				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();
-				}
-				else {
-					title = channelName;
-				}
-
-				items.Add(new CheckBoxItem<ulong>(channelId) {
-					Title = title,
-					Checked = included.Contains(channelId)
-				});
-			}
-
-			var result = await OpenIdFilterDialog(window, "Included Channels", items);
-			if (result != null) {
-				IncludedChannels = result;
-			}
-		}
-
-		public async void OpenUserFilterDialog() {
-			var items = new List<CheckBoxItem<ulong>>();
-			var included = IncludedUsers;
-
-			foreach (var user in db.GetAllUsers()) {
-				var name = user.Name;
-				var discriminator = user.Discriminator;
-
-				items.Add(new CheckBoxItem<ulong>(user.Id) {
-					Title = discriminator == null ? name : name + " #" + discriminator,
-					Checked = included.Contains(user.Id)
-				});
-			}
-
-			var result = await OpenIdFilterDialog(window, "Included Users", items);
-			if (result != null) {
-				IncludedUsers = result;
-			}
-		}
-
-		private void UpdateChannelFilterLabel() {
-			long total = db.Statistics.TotalChannels;
-			long included = FilterByChannel ? IncludedChannels.Count : total;
-			ChannelFilterLabel = "Selected " + included.Format() + " / " + total.Pluralize("channel") + ".";
-		}
-
-		private void UpdateUserFilterLabel() {
-			long total = db.Statistics.TotalUsers;
-			long included = FilterByUser ? IncludedUsers.Count : total;
-			UserFilterLabel = "Selected " + included.Format() + " / " + total.Pluralize("user") + ".";
-		}
-
-		public MessageFilter CreateFilter() {
-			MessageFilter filter = new();
-
-			if (FilterByDate) {
-				filter.StartDate = StartDate;
-				filter.EndDate = EndDate?.AddDays(1).AddMilliseconds(-1);
-			}
-
-			if (FilterByChannel) {
-				filter.ChannelIds = new HashSet<ulong>(IncludedChannels);
-			}
-
-			if (FilterByUser) {
-				filter.UserIds = new HashSet<ulong>(IncludedUsers);
-			}
-
-			return filter;
-		}
-
-		private static async Task<HashSet<ulong>?> OpenIdFilterDialog(Window window, string title, List<CheckBoxItem<ulong>> items) {
-			items.Sort(static (item1, item2) => item1.Title.CompareTo(item2.Title));
-
-			var model = new CheckBoxDialogModel<ulong>(items) {
-				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;
-		}
-	}
-}

app/Desktop/Main/Controls/MessageFilterPanel.axaml

@@ -0,0 +1,63 @@
+<UserControl 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:controls="clr-namespace:DHT.Desktop.Main.Controls"
+             mc:Ignorable="d"
+             x:Class="DHT.Desktop.Main.Controls.MessageFilterPanel">
+
+    <Design.DataContext>
+        <controls:MessageFilterPanelModel />
+    </Design.DataContext>
+
+    <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>
+        <Style Selector="Grid > CalendarDatePicker">
+            <Setter Property="CornerRadius" Value="0" />
+            <Setter Property="HorizontalAlignment" Value="Stretch" />
+            <Setter Property="HorizontalContentAlignment" Value="Center" />
+            <Setter Property="VerticalAlignment" Value="Center" />
+            <Setter Property="VerticalContentAlignment" Value="Center" />
+            <Setter Property="IsTodayHighlighted" Value="True" />
+            <Setter Property="SelectedDateFormat" Value="Short" />
+        </Style>
+        <Style Selector="Button">
+            <Setter Property="Margin" Value="0 0 0 8" />
+        </Style>
+    </UserControl.Styles>
+
+    <StackPanel>
+        <TextBlock Text="{Binding FilterStatisticsText}" />
+        <WrapPanel>
+            <StackPanel>
+                <CheckBox IsChecked="{Binding FilterByDate}">Filter by Date</CheckBox>
+                <Grid ColumnDefinitions="Auto, 4, 125" RowDefinitions="Auto, 4, Auto" Margin="4 0">
+                    <Label Grid.Row="0" Grid.Column="0">From:</Label>
+                    <CalendarDatePicker Grid.Row="0" Grid.Column="2" x:Name="StartDatePicker" IsEnabled="{Binding FilterByDate}" SelectedDateChanged="CalendarDatePicker_OnSelectedDateChanged" />
+                    <Label Grid.Row="2" Grid.Column="0">To:</Label>
+                    <CalendarDatePicker Grid.Row="2" Grid.Column="2" x:Name="EndDatePicker" IsEnabled="{Binding FilterByDate}" SelectedDateChanged="CalendarDatePicker_OnSelectedDateChanged" />
+                </Grid>
+            </StackPanel>
+            <StackPanel>
+                <CheckBox IsChecked="{Binding FilterByChannel}">Filter by Channel</CheckBox>
+                <Button Command="{Binding OpenChannelFilterDialog}" IsEnabled="{Binding FilterByChannel}">Select Channels...</Button>
+                <TextBlock Text="{Binding ChannelFilterLabel}" />
+            </StackPanel>
+            <StackPanel>
+                <CheckBox IsChecked="{Binding FilterByUser}">Filter by User</CheckBox>
+                <Button Command="{Binding OpenUserFilterDialog}" IsEnabled="{Binding FilterByUser}">Select Users...</Button>
+                <TextBlock Text="{Binding UserFilterLabel}" />
+            </StackPanel>
+        </WrapPanel>
+    </StackPanel>
+
+</UserControl>

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

@@ -0,0 +1,26 @@
+using System.Diagnostics.CodeAnalysis;
+using Avalonia.Controls;
+
+namespace DHT.Desktop.Main.Controls;
+
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class MessageFilterPanel : UserControl {
+	public MessageFilterPanel() {
+		InitializeComponent();
+
+		var culture = Program.Culture;
+		foreach (var picker in new CalendarDatePicker[] { StartDatePicker, EndDatePicker }) {
+			picker.FirstDayOfWeek = culture.DateTimeFormat.FirstDayOfWeek;
+			picker.SelectedDateFormat = CalendarDatePickerFormat.Custom;
+			picker.CustomDateFormatString = culture.DateTimeFormat.ShortDatePattern;
+			picker.Watermark = culture.DateTimeFormat.ShortDatePattern;
+		}
+	}
+
+	public void CalendarDatePicker_OnSelectedDateChanged(object? sender, SelectionChangedEventArgs e) {
+		if (DataContext is MessageFilterPanelModel model) {
+			model.StartDate = StartDatePicker.SelectedDate;
+			model.EndDate = EndDatePicker.SelectedDate;
+		}
+	}
+}

app/Desktop/Main/Controls/MessageFilterPanelModel.cs

@@ -0,0 +1,285 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Avalonia.Controls;
+using DHT.Desktop.Common;
+using DHT.Desktop.Dialogs.CheckBox;
+using DHT.Desktop.Dialogs.Message;
+using DHT.Server.Data;
+using DHT.Server.Data.Filters;
+using DHT.Server.Database;
+using DHT.Utils.Models;
+using DHT.Utils.Tasks;
+
+namespace DHT.Desktop.Main.Controls;
+
+sealed class MessageFilterPanelModel : BaseModel, IDisposable {
+	private static readonly HashSet<string> FilterProperties = new () {
+		nameof(FilterByDate),
+		nameof(StartDate),
+		nameof(EndDate),
+		nameof(FilterByChannel),
+		nameof(IncludedChannels),
+		nameof(FilterByUser),
+		nameof(IncludedUsers)
+	};
+
+	public string FilterStatisticsText { get; private set; } = "";
+
+	public event PropertyChangedEventHandler? FilterPropertyChanged;
+
+	public bool HasAnyFilters => FilterByDate || FilterByChannel || FilterByUser;
+
+	private bool filterByDate = false;
+	private DateTime? startDate = null;
+	private DateTime? endDate = null;
+	private bool filterByChannel = false;
+	private HashSet<ulong>? includedChannels = null;
+	private bool filterByUser = false;
+	private HashSet<ulong>? includedUsers = null;
+
+	public bool FilterByDate {
+		get => filterByDate;
+		set => Change(ref filterByDate, value);
+	}
+
+	public DateTime? StartDate {
+		get => startDate;
+		set => Change(ref startDate, value);
+	}
+
+	public DateTime? EndDate {
+		get => endDate;
+		set => Change(ref endDate, value);
+	}
+
+	public bool FilterByChannel {
+		get => filterByChannel;
+		set => Change(ref filterByChannel, value);
+	}
+
+	public HashSet<ulong> IncludedChannels {
+		get => includedChannels ?? db.GetAllChannels().Select(static channel => channel.Id).ToHashSet();
+		set => Change(ref includedChannels, value);
+	}
+
+	public bool FilterByUser {
+		get => filterByUser;
+		set => Change(ref filterByUser, value);
+	}
+
+	public HashSet<ulong> IncludedUsers {
+		get => includedUsers ?? db.GetAllUsers().Select(static user => user.Id).ToHashSet();
+		set => Change(ref includedUsers, value);
+	}
+
+	private string channelFilterLabel = "";
+
+	public string ChannelFilterLabel {
+		get => channelFilterLabel;
+		set => Change(ref channelFilterLabel, value);
+	}
+
+	private string userFilterLabel = "";
+
+	public string UserFilterLabel {
+		get => userFilterLabel;
+		set => Change(ref userFilterLabel, value);
+	}
+
+	private readonly Window window;
+	private readonly IDatabaseFile db;
+	private readonly string verb;
+
+	private readonly AsyncValueComputer<long> exportedMessageCountComputer;
+	private long? exportedMessageCount;
+	private long? totalMessageCount;
+
+	[Obsolete("Designer")]
+	public MessageFilterPanelModel() : this(null!, DummyDatabaseFile.Instance) {}
+
+	public MessageFilterPanelModel(Window window, IDatabaseFile db, string verb = "Matches") {
+		this.window = window;
+		this.db = db;
+		this.verb = verb;
+
+		this.exportedMessageCountComputer = AsyncValueComputer<long>.WithResultProcessor(SetExportedMessageCount).Build();
+
+		UpdateFilterStatistics();
+		UpdateChannelFilterLabel();
+		UpdateUserFilterLabel();
+
+		PropertyChanged += OnPropertyChanged;
+		db.Statistics.PropertyChanged += OnDbStatisticsChanged;
+	}
+
+	public void Dispose() {
+		db.Statistics.PropertyChanged -= OnDbStatisticsChanged;
+	}
+
+	private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName != null && FilterProperties.Contains(e.PropertyName)) {
+			UpdateFilterStatistics();
+			FilterPropertyChanged?.Invoke(sender, e);
+		}
+
+		if (e.PropertyName is nameof(FilterByChannel) or nameof(IncludedChannels)) {
+			UpdateChannelFilterLabel();
+		}
+		else if (e.PropertyName is nameof(FilterByUser) or nameof(IncludedUsers)) {
+			UpdateUserFilterLabel();
+		}
+	}
+
+	private void OnDbStatisticsChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName == nameof(DatabaseStatistics.TotalMessages)) {
+			totalMessageCount = db.Statistics.TotalMessages;
+			UpdateFilterStatistics();
+		}
+		else if (e.PropertyName == nameof(DatabaseStatistics.TotalChannels)) {
+			UpdateChannelFilterLabel();
+		}
+		else if (e.PropertyName == nameof(DatabaseStatistics.TotalUsers)) {
+			UpdateUserFilterLabel();
+		}
+	}
+
+	private void UpdateFilterStatistics() {
+		var filter = CreateFilter();
+		if (filter.IsEmpty) {
+			exportedMessageCountComputer.Cancel();
+			exportedMessageCount = totalMessageCount;
+			UpdateFilterStatisticsText();
+		}
+		else {
+			exportedMessageCount = null;
+			UpdateFilterStatisticsText();
+			exportedMessageCountComputer.Compute(() => db.CountMessages(filter));
+		}
+	}
+
+	private void SetExportedMessageCount(long exportedMessageCount) {
+		this.exportedMessageCount = exportedMessageCount;
+		UpdateFilterStatisticsText();
+	}
+
+	private void UpdateFilterStatisticsText() {
+		var exportedMessageCountStr = exportedMessageCount?.Format() ?? "(...)";
+		var totalMessageCountStr = totalMessageCount?.Format() ?? "(...)";
+
+		FilterStatisticsText = verb + " " + exportedMessageCountStr + " out of " + totalMessageCountStr + " message" + (totalMessageCount is null or 1 ? "." : "s.");
+		OnPropertyChanged(nameof(FilterStatisticsText));
+	}
+
+	public async void OpenChannelFilterDialog() {
+		var servers = db.GetAllServers().ToDictionary(static server => server.Id);
+		var items = new List<CheckBoxItem<ulong>>();
+		var included = IncludedChannels;
+
+		foreach (var channel in db.GetAllChannels()) {
+			var channelId = channel.Id;
+			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();
+			}
+			else {
+				title = channelName;
+			}
+
+			items.Add(new CheckBoxItem<ulong>(channelId) {
+				Title = title,
+				Checked = included.Contains(channelId)
+			});
+		}
+
+		var result = await OpenIdFilterDialog(window, "Included Channels", items);
+		if (result != null) {
+			IncludedChannels = result;
+		}
+	}
+
+	public async void OpenUserFilterDialog() {
+		var items = new List<CheckBoxItem<ulong>>();
+		var included = IncludedUsers;
+
+		foreach (var user in db.GetAllUsers()) {
+			var name = user.Name;
+			var discriminator = user.Discriminator;
+
+			items.Add(new CheckBoxItem<ulong>(user.Id) {
+				Title = discriminator == null ? name : name + " #" + discriminator,
+				Checked = included.Contains(user.Id)
+			});
+		}
+
+		var result = await OpenIdFilterDialog(window, "Included Users", items);
+		if (result != null) {
+			IncludedUsers = result;
+		}
+	}
+
+	private void UpdateChannelFilterLabel() {
+		long total = db.Statistics.TotalChannels;
+		long included = FilterByChannel ? IncludedChannels.Count : total;
+		ChannelFilterLabel = "Selected " + included.Format() + " / " + total.Pluralize("channel") + ".";
+	}
+
+	private void UpdateUserFilterLabel() {
+		long total = db.Statistics.TotalUsers;
+		long included = FilterByUser ? IncludedUsers.Count : total;
+		UserFilterLabel = "Selected " + included.Format() + " / " + total.Pluralize("user") + ".";
+	}
+
+	public MessageFilter CreateFilter() {
+		MessageFilter filter = new();
+
+		if (FilterByDate) {
+			filter.StartDate = StartDate;
+			filter.EndDate = EndDate?.AddDays(1).AddMilliseconds(-1);
+		}
+
+		if (FilterByChannel) {
+			filter.ChannelIds = new HashSet<ulong>(IncludedChannels);
+		}
+
+		if (FilterByUser) {
+			filter.UserIds = new HashSet<ulong>(IncludedUsers);
+		}
+
+		return filter;
+	}
+
+	private static async Task<HashSet<ulong>?> OpenIdFilterDialog(Window window, string title, List<CheckBoxItem<ulong>> items) {
+		items.Sort(static (item1, item2) => item1.Title.CompareTo(item2.Title));
+
+		var model = new CheckBoxDialogModel<ulong>(items) {
+			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;
+	}
+}

app/Desktop/Main/Controls/ServerConfigurationPanel.axaml

@@ -24,7 +24,7 @@
     <StackPanel>
         <Button Command="{Binding OnClickToggleServerButton}" Content="{Binding ToggleServerButtonText}" IsEnabled="{Binding IsToggleServerButtonEnabled}" />
         <TextBlock TextWrapping="Wrap" Margin="0 15">
-            The following settings determine how the tracking script communicates with this application. If you change them, you will have to copy and apply 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 again.
         </TextBlock>
         <WrapPanel>
             <StackPanel>

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

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Controls {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class ServerConfigurationPanel : UserControl {
-		public ServerConfigurationPanel() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Controls;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class ServerConfigurationPanel : UserControl {
+	public ServerConfigurationPanel() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Controls/ServerConfigurationPanelModel.cs

@@ -6,111 +6,111 @@ using DHT.Server.Database;
 using DHT.Server.Service;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Controls {
-	sealed class ServerConfigurationPanelModel : BaseModel, IDisposable {
-		private string inputPort;
+namespace DHT.Desktop.Main.Controls;
 
-		public string InputPort {
-			get => inputPort;
-			set {
-				Change(ref inputPort, value);
-				OnPropertyChanged(nameof(HasMadeChanges));
-			}
-		}
+sealed class ServerConfigurationPanelModel : BaseModel, IDisposable {
+	private string inputPort;
 
-		private string inputToken;
-
-		public string InputToken {
-			get => inputToken;
-			set {
-				Change(ref inputToken, value);
-				OnPropertyChanged(nameof(HasMadeChanges));
-			}
-		}
-
-		public bool HasMadeChanges => ServerManager.Port.ToString() != InputPort || ServerManager.Token != InputToken;
-
-		private bool isToggleServerButtonEnabled = true;
-
-		public bool IsToggleServerButtonEnabled {
-			get => isToggleServerButtonEnabled;
-			set => Change(ref isToggleServerButtonEnabled, value);
-		}
-
-		public string ToggleServerButtonText => serverManager.IsRunning ? "Stop Server" : "Start Server";
-
-		public event EventHandler<StatusBarModel.Status>? ServerStatusChanged;
-
-		private readonly Window window;
-		private readonly ServerManager serverManager;
-
-		[Obsolete("Designer")]
-		public ServerConfigurationPanelModel() : this(null!, new ServerManager(DummyDatabaseFile.Instance)) {}
-
-		public ServerConfigurationPanelModel(Window window, ServerManager serverManager) {
-			this.window = window;
-			this.serverManager = serverManager;
-			this.inputPort = ServerManager.Port.ToString();
-			this.inputToken = ServerManager.Token;
-		}
-
-		public void Initialize() {
-			ServerLauncher.ServerStatusChanged += ServerLauncherOnServerStatusChanged;
-		}
-
-		public void Dispose() {
-			ServerLauncher.ServerStatusChanged -= ServerLauncherOnServerStatusChanged;
-		}
-
-		private void ServerLauncherOnServerStatusChanged(object? sender, EventArgs e) {
-			ServerStatusChanged?.Invoke(this, serverManager.IsRunning ? StatusBarModel.Status.Ready : StatusBarModel.Status.Stopped);
-			OnPropertyChanged(nameof(ToggleServerButtonText));
-			IsToggleServerButtonEnabled = true;
-		}
-
-		private void BeforeServerStart() {
-			IsToggleServerButtonEnabled = false;
-			ServerStatusChanged?.Invoke(this, StatusBarModel.Status.Starting);
-		}
-
-		private void StartServer() {
-			BeforeServerStart();
-			serverManager.Launch();
-		}
-
-		private void StopServer() {
-			IsToggleServerButtonEnabled = false;
-			ServerStatusChanged?.Invoke(this, StatusBarModel.Status.Stopping);
-			serverManager.Stop();
-		}
-
-		public void OnClickToggleServerButton() {
-			if (serverManager.IsRunning) {
-				StopServer();
-			}
-			else {
-				StartServer();
-			}
-		}
-
-		public void OnClickRandomizeToken() {
-			InputToken = ServerUtils.GenerateRandomToken(20);
-		}
-
-		public async void OnClickApplyChanges() {
-			if (!ushort.TryParse(InputPort, out ushort port)) {
-				await Dialog.ShowOk(window, "Invalid Port", "Port must be a number between 0 and 65535.");
-				return;
-			}
-
-			BeforeServerStart();
-			serverManager.Relaunch(port, InputToken);
+	public string InputPort {
+		get => inputPort;
+		set {
+			Change(ref inputPort, value);
 			OnPropertyChanged(nameof(HasMadeChanges));
 		}
+	}
 
-		public void OnClickCancelChanges() {
-			InputPort = ServerManager.Port.ToString();
-			InputToken = ServerManager.Token;
+	private string inputToken;
+
+	public string InputToken {
+		get => inputToken;
+		set {
+			Change(ref inputToken, value);
+			OnPropertyChanged(nameof(HasMadeChanges));
 		}
 	}
+
+	public bool HasMadeChanges => ServerManager.Port.ToString() != InputPort || ServerManager.Token != InputToken;
+
+	private bool isToggleServerButtonEnabled = true;
+
+	public bool IsToggleServerButtonEnabled {
+		get => isToggleServerButtonEnabled;
+		set => Change(ref isToggleServerButtonEnabled, value);
+	}
+
+	public string ToggleServerButtonText => serverManager.IsRunning ? "Stop Server" : "Start Server";
+
+	public event EventHandler<StatusBarModel.Status>? ServerStatusChanged;
+
+	private readonly Window window;
+	private readonly ServerManager serverManager;
+
+	[Obsolete("Designer")]
+	public ServerConfigurationPanelModel() : this(null!, new ServerManager(DummyDatabaseFile.Instance)) {}
+
+	public ServerConfigurationPanelModel(Window window, ServerManager serverManager) {
+		this.window = window;
+		this.serverManager = serverManager;
+		this.inputPort = ServerManager.Port.ToString();
+		this.inputToken = ServerManager.Token;
+	}
+
+	public void Initialize() {
+		ServerLauncher.ServerStatusChanged += ServerLauncherOnServerStatusChanged;
+	}
+
+	public void Dispose() {
+		ServerLauncher.ServerStatusChanged -= ServerLauncherOnServerStatusChanged;
+	}
+
+	private void ServerLauncherOnServerStatusChanged(object? sender, EventArgs e) {
+		ServerStatusChanged?.Invoke(this, serverManager.IsRunning ? StatusBarModel.Status.Ready : StatusBarModel.Status.Stopped);
+		OnPropertyChanged(nameof(ToggleServerButtonText));
+		IsToggleServerButtonEnabled = true;
+	}
+
+	private void BeforeServerStart() {
+		IsToggleServerButtonEnabled = false;
+		ServerStatusChanged?.Invoke(this, StatusBarModel.Status.Starting);
+	}
+
+	private void StartServer() {
+		BeforeServerStart();
+		serverManager.Launch();
+	}
+
+	private void StopServer() {
+		IsToggleServerButtonEnabled = false;
+		ServerStatusChanged?.Invoke(this, StatusBarModel.Status.Stopping);
+		serverManager.Stop();
+	}
+
+	public void OnClickToggleServerButton() {
+		if (serverManager.IsRunning) {
+			StopServer();
+		}
+		else {
+			StartServer();
+		}
+	}
+
+	public void OnClickRandomizeToken() {
+		InputToken = ServerUtils.GenerateRandomToken(20);
+	}
+
+	public async void OnClickApplyChanges() {
+		if (!ushort.TryParse(InputPort, out ushort port)) {
+			await Dialog.ShowOk(window, "Invalid Port", "Port must be a number between 0 and 65535.");
+			return;
+		}
+
+		BeforeServerStart();
+		serverManager.Relaunch(port, InputToken);
+		OnPropertyChanged(nameof(HasMadeChanges));
+	}
+
+	public void OnClickCancelChanges() {
+		InputPort = ServerManager.Port.ToString();
+		InputToken = ServerManager.Token;
+	}
 }

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

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Controls {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class StatusBar : UserControl {
-		public StatusBar() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Controls;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class StatusBar : UserControl {
+	public StatusBar() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Controls/StatusBarModel.cs

@@ -2,44 +2,44 @@ using System;
 using DHT.Server.Database;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Controls {
-	sealed class StatusBarModel : BaseModel {
-		public DatabaseStatistics DatabaseStatistics { get; }
+namespace DHT.Desktop.Main.Controls;
 
-		private Status status = Status.Stopped;
+sealed class StatusBarModel : BaseModel {
+	public DatabaseStatistics DatabaseStatistics { get; }
 
-		public Status CurrentStatus {
-			get => status;
-			set {
-				status = value;
-				OnPropertyChanged(nameof(StatusText));
-			}
-		}
+	private Status status = Status.Stopped;
 
-		public string StatusText {
-			get {
-				return CurrentStatus switch {
-					Status.Starting => "STARTING",
-					Status.Ready    => "READY",
-					Status.Stopping => "STOPPING",
-					Status.Stopped  => "STOPPED",
-					_               => ""
-				};
-			}
-		}
-
-		[Obsolete("Designer")]
-		public StatusBarModel() : this(new DatabaseStatistics()) {}
-
-		public StatusBarModel(DatabaseStatistics databaseStatistics) {
-			this.DatabaseStatistics = databaseStatistics;
-		}
-
-		public enum Status {
-			Starting,
-			Ready,
-			Stopping,
-			Stopped
+	public Status CurrentStatus {
+		get => status;
+		set {
+			status = value;
+			OnPropertyChanged(nameof(StatusText));
 		}
 	}
+
+	public string StatusText {
+		get {
+			return CurrentStatus switch {
+				Status.Starting => "STARTING",
+				Status.Ready    => "READY",
+				Status.Stopping => "STOPPING",
+				Status.Stopped  => "STOPPED",
+				_               => ""
+			};
+		}
+	}
+
+	[Obsolete("Designer")]
+	public StatusBarModel() : this(new DatabaseStatistics()) {}
+
+	public StatusBarModel(DatabaseStatistics databaseStatistics) {
+		this.DatabaseStatistics = databaseStatistics;
+	}
+
+	public enum Status {
+		Starting,
+		Ready,
+		Stopping,
+		Stopped
+	}
 }

app/Desktop/Main/MainWindow.axaml

@@ -8,7 +8,7 @@
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
         Width="800" Height="500"
-        MinWidth="500" MinHeight="275"
+        MinWidth="520" MinHeight="300"
         WindowStartupLocation="CenterScreen"
         Closed="OnClosed">
 

app/Desktop/Main/MainWindow.axaml.cs

@@ -1,34 +1,35 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
-using Avalonia;
+using System.IO;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
+using DHT.Desktop.Main.Pages;
 using JetBrains.Annotations;
 
-namespace DHT.Desktop.Main {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class MainWindow : Window {
-		[UsedImplicitly]
-		public MainWindow() {
-			InitializeComponent(Arguments.Empty);
+namespace DHT.Desktop.Main;
+
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class MainWindow : Window {
+	[UsedImplicitly]
+	public MainWindow() {
+		InitializeComponent();
+		DataContext = new MainWindowModel(this, Arguments.Empty);
+	}
+
+	internal MainWindow(Arguments args) {
+		InitializeComponent();
+		DataContext = new MainWindowModel(this, args);
+	}
+
+	public void OnClosed(object? sender, EventArgs e) {
+		if (DataContext is IDisposable disposable) {
+			disposable.Dispose();
 		}
 
-		internal MainWindow(Arguments args) {
-			InitializeComponent(args);
-		}
-
-		private void InitializeComponent(Arguments args) {
-			AvaloniaXamlLoader.Load(this);
-			DataContext = new MainWindowModel(this, args);
-
-			#if DEBUG
-			this.AttachDevTools();
-			#endif
-		}
-
-		public void OnClosed(object? sender, EventArgs e) {
-			if (DataContext is IDisposable disposable) {
-				disposable.Dispose();
+		foreach (var temporaryFile in ViewerPageModel.TemporaryFiles) {
+			try {
+				File.Delete(temporaryFile);
+			} catch (Exception) {
+				// ignored
 			}
 		}
 	}

app/Desktop/Main/MainWindowModel.cs

@@ -10,107 +10,107 @@ using DHT.Desktop.Server;
 using DHT.Server.Database;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main {
-	sealed class MainWindowModel : BaseModel, IDisposable {
-		private const string DefaultTitle = "Discord History Tracker";
+namespace DHT.Desktop.Main;
 
-		public string Title { get; private set; } = DefaultTitle;
+sealed class MainWindowModel : BaseModel, IDisposable {
+	private const string DefaultTitle = "Discord History Tracker";
 
-		public UserControl CurrentScreen { get; private set; }
-		
-		private readonly WelcomeScreen welcomeScreen;
-		private readonly WelcomeScreenModel welcomeScreenModel;
+	public string Title { get; private set; } = DefaultTitle;
 
-		private MainContentScreen? mainContentScreen;
-		private MainContentScreenModel? mainContentScreenModel;
+	public UserControl CurrentScreen { get; private set; }
 
-		private readonly Window window;
+	private readonly WelcomeScreen welcomeScreen;
+	private readonly WelcomeScreenModel welcomeScreenModel;
 
-		private IDatabaseFile? db;
+	private MainContentScreen? mainContentScreen;
+	private MainContentScreenModel? mainContentScreenModel;
 
-		[Obsolete("Designer")]
-		public MainWindowModel() : this(null!, Arguments.Empty) {}
+	private readonly Window window;
 
-		public MainWindowModel(Window window, Arguments args) {
-			this.window = window;
+	private IDatabaseFile? db;
 
-			welcomeScreenModel = new WelcomeScreenModel(window);
-			welcomeScreen = new WelcomeScreen { DataContext = welcomeScreenModel };
-			CurrentScreen = welcomeScreen;
+	[Obsolete("Designer")]
+	public MainWindowModel() : this(null!, Arguments.Empty) {}
 
-			welcomeScreenModel.PropertyChanged += WelcomeScreenModelOnPropertyChanged;
+	public MainWindowModel(Window window, Arguments args) {
+		this.window = window;
 
-			var dbFile = args.DatabaseFile;
-			if (!string.IsNullOrWhiteSpace(dbFile)) {
-				async void OnWindowOpened(object? o, EventArgs eventArgs) {
-					window.Opened -= OnWindowOpened;
+		welcomeScreenModel = new WelcomeScreenModel(window);
+		welcomeScreen = new WelcomeScreen { DataContext = welcomeScreenModel };
+		CurrentScreen = welcomeScreen;
 
-					// https://github.com/AvaloniaUI/Avalonia/issues/3071
-					if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
-						await Task.Delay(500);
-					}
+		welcomeScreenModel.PropertyChanged += WelcomeScreenModelOnPropertyChanged;
 
-					if (File.Exists(dbFile)) {
-						await welcomeScreenModel.OpenOrCreateDatabaseFromPath(dbFile);
-					}
-					else {
-						await Dialog.ShowOk(window, "Database Error", "Database file not found:\n" + dbFile);
-					}
+		var dbFile = args.DatabaseFile;
+		if (!string.IsNullOrWhiteSpace(dbFile)) {
+			async void OnWindowOpened(object? o, EventArgs eventArgs) {
+				window.Opened -= OnWindowOpened;
+
+				// https://github.com/AvaloniaUI/Avalonia/issues/3071
+				if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
+					await Task.Delay(500);
 				}
 
-				window.Opened += OnWindowOpened;
-			}
-
-			if (args.ServerPort != null) {
-				ServerManager.Port = args.ServerPort.Value;
-			}
-
-			if (args.ServerToken != null) {
-				ServerManager.Token = args.ServerToken;
-			}
-		}
-
-		private async void WelcomeScreenModelOnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
-			if (e.PropertyName == nameof(welcomeScreenModel.Db)) {
-				if (mainContentScreenModel != null) {
-					mainContentScreenModel.DatabaseClosed -= MainContentScreenModelOnDatabaseClosed;
-					mainContentScreenModel.Dispose();
-				}
-
-				db?.Dispose();
-				db = welcomeScreenModel.Db;
-
-				if (db == null) {
-					Title = DefaultTitle;
-					mainContentScreenModel = null;
-					mainContentScreen = null;
-					CurrentScreen = welcomeScreen;
+				if (File.Exists(dbFile)) {
+					await welcomeScreenModel.OpenOrCreateDatabaseFromPath(dbFile);
 				}
 				else {
-					Title = Path.GetFileName(db.Path) + " - " + DefaultTitle;
-					mainContentScreenModel = new MainContentScreenModel(window, db);
-					await mainContentScreenModel.Initialize();
-					mainContentScreenModel.DatabaseClosed += MainContentScreenModelOnDatabaseClosed;
-					mainContentScreen = new MainContentScreen { DataContext = mainContentScreenModel };
-					CurrentScreen = mainContentScreen;
+					await Dialog.ShowOk(window, "Database Error", "Database file not found:\n" + dbFile);
 				}
-
-				OnPropertyChanged(nameof(CurrentScreen));
-				OnPropertyChanged(nameof(Title));
-
-				window.Focus();
 			}
+
+			window.Opened += OnWindowOpened;
 		}
 
-		private void MainContentScreenModelOnDatabaseClosed(object? sender, EventArgs e) {
-			welcomeScreenModel.CloseDatabase();
+		if (args.ServerPort != null) {
+			ServerManager.Port = args.ServerPort.Value;
 		}
 
-		public void Dispose() {
-			welcomeScreenModel.Dispose();
-			mainContentScreenModel?.Dispose();
-			db?.Dispose();
-			db = null;
+		if (args.ServerToken != null) {
+			ServerManager.Token = args.ServerToken;
 		}
 	}
+
+	private async void WelcomeScreenModelOnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName == nameof(welcomeScreenModel.Db)) {
+			if (mainContentScreenModel != null) {
+				mainContentScreenModel.DatabaseClosed -= MainContentScreenModelOnDatabaseClosed;
+				mainContentScreenModel.Dispose();
+			}
+
+			db?.Dispose();
+			db = welcomeScreenModel.Db;
+
+			if (db == null) {
+				Title = DefaultTitle;
+				mainContentScreenModel = null;
+				mainContentScreen = null;
+				CurrentScreen = welcomeScreen;
+			}
+			else {
+				Title = Path.GetFileName(db.Path) + " - " + DefaultTitle;
+				mainContentScreenModel = new MainContentScreenModel(window, db);
+				await mainContentScreenModel.Initialize();
+				mainContentScreenModel.DatabaseClosed += MainContentScreenModelOnDatabaseClosed;
+				mainContentScreen = new MainContentScreen { DataContext = mainContentScreenModel };
+				CurrentScreen = mainContentScreen;
+			}
+
+			OnPropertyChanged(nameof(CurrentScreen));
+			OnPropertyChanged(nameof(Title));
+
+			window.Focus();
+		}
+	}
+
+	private void MainContentScreenModelOnDatabaseClosed(object? sender, EventArgs e) {
+		welcomeScreenModel.CloseDatabase();
+	}
+
+	public void Dispose() {
+		welcomeScreenModel.Dispose();
+		mainContentScreenModel?.Dispose();
+		db?.Dispose();
+		db = null;
+	}
 }

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

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Pages {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class AdvancedPage : UserControl {
-		public AdvancedPage() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Pages;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class AdvancedPage : UserControl {
+	public AdvancedPage() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Pages/AdvancedPageModel.cs

@@ -6,34 +6,34 @@ using DHT.Desktop.Server;
 using DHT.Server.Database;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Pages {
-	sealed class AdvancedPageModel : BaseModel, IDisposable {
-		public ServerConfigurationPanelModel ServerConfigurationModel { get; }
+namespace DHT.Desktop.Main.Pages;
 
-		private readonly Window window;
-		private readonly IDatabaseFile db;
+sealed class AdvancedPageModel : BaseModel, IDisposable {
+	public ServerConfigurationPanelModel ServerConfigurationModel { get; }
 
-		[Obsolete("Designer")]
-		public AdvancedPageModel() : this(null!, DummyDatabaseFile.Instance, new ServerManager(DummyDatabaseFile.Instance)) {}
+	private readonly Window window;
+	private readonly IDatabaseFile db;
 
-		public AdvancedPageModel(Window window, IDatabaseFile db, ServerManager serverManager) {
-			this.window = window;
-			this.db = db;
+	[Obsolete("Designer")]
+	public AdvancedPageModel() : this(null!, DummyDatabaseFile.Instance, new ServerManager(DummyDatabaseFile.Instance)) {}
 
-			ServerConfigurationModel = new ServerConfigurationPanelModel(window, serverManager);
-		}
+	public AdvancedPageModel(Window window, IDatabaseFile db, ServerManager serverManager) {
+		this.window = window;
+		this.db = db;
 
-		public void Initialize() {
-			ServerConfigurationModel.Initialize();
-		}
+		ServerConfigurationModel = new ServerConfigurationPanelModel(window, serverManager);
+	}
 
-		public void Dispose() {
-			ServerConfigurationModel.Dispose();
-		}
+	public void Initialize() {
+		ServerConfigurationModel.Initialize();
+	}
 
-		public async void VacuumDatabase() {
-			db.Vacuum();
-			await Dialog.ShowOk(window, "Vacuum Database", "Done.");
-		}
+	public void Dispose() {
+		ServerConfigurationModel.Dispose();
+	}
+
+	public async void VacuumDatabase() {
+		db.Vacuum();
+		await Dialog.ShowOk(window, "Vacuum Database", "Done.");
 	}
 }

app/Desktop/Main/Pages/AttachmentsPage.axaml

@@ -0,0 +1,54 @@
+<UserControl 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:pages="clr-namespace:DHT.Desktop.Main.Pages"
+             xmlns:controls="clr-namespace:DHT.Desktop.Main.Controls"
+             mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+             x:Class="DHT.Desktop.Main.Pages.AttachmentsPage">
+
+    <Design.DataContext>
+        <pages:AttachmentsPageModel />
+    </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>
+        <Style Selector="DataGridColumnHeader:nth-child(2)">
+            <Setter Property="HorizontalContentAlignment" Value="Right" />
+        </Style>
+        <Style Selector="DataGridColumnHeader:nth-child(3)">
+            <Setter Property="HorizontalContentAlignment" Value="Right" />
+        </Style>
+        <Style Selector="DataGridCell.right">
+            <Setter Property="HorizontalContentAlignment" Value="Right" />
+        </Style>
+    </UserControl.Styles>
+
+    <StackPanel Orientation="Vertical" Spacing="20">
+        <DockPanel>
+            <Button Command="{Binding OnClickToggleDownload}" Content="{Binding ToggleDownloadButtonText}" IsEnabled="{Binding IsToggleDownloadButtonEnabled}" DockPanel.Dock="Left" />
+            <TextBlock Text="{Binding DownloadMessage}" Margin="10 0 0 0" VerticalAlignment="Center" DockPanel.Dock="Left" />
+            <ProgressBar Value="{Binding DownloadProgress}" IsVisible="{Binding IsDownloading}" Margin="15 0" VerticalAlignment="Center" DockPanel.Dock="Right" />
+        </DockPanel>
+        <controls:AttachmentFilterPanel DataContext="{Binding FilterModel}" IsEnabled="{Binding !DataContext.IsDownloading, RelativeSource={RelativeSource AncestorType=UserControl}}" />
+        <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>
+                        <DataGridTextColumn Header="State" Binding="{Binding State}" Width="*" />
+                        <DataGridTextColumn Header="Attachments" Binding="{Binding Items, Converter={StaticResource NumberValueConverter}}" Width="*" CellStyleClasses="right" />
+                        <DataGridTextColumn Header="Size" Binding="{Binding Size, Converter={StaticResource BytesValueConverter}}" Width="*" CellStyleClasses="right" />
+                    </DataGrid.Columns>
+                </DataGrid>
+            </Expander>
+            <StackPanel Orientation="Horizontal" Spacing="10">
+                <Button Command="{Binding OnClickRetryFailedDownloads}" IsEnabled="{Binding HasFailedDownloads}">Retry Failed Downloads</Button>
+            </StackPanel>
+        </StackPanel>
+    </StackPanel>
+</UserControl>

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

@@ -0,0 +1,11 @@
+using System.Diagnostics.CodeAnalysis;
+using Avalonia.Controls;
+
+namespace DHT.Desktop.Main.Pages;
+
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class AttachmentsPage : UserControl {
+	public AttachmentsPage() {
+		InitializeComponent();
+	}
+}

app/Desktop/Main/Pages/AttachmentsPageModel.cs

@@ -0,0 +1,205 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Threading;
+using Avalonia.Threading;
+using DHT.Desktop.Common;
+using DHT.Desktop.Main.Controls;
+using DHT.Server.Data;
+using DHT.Server.Data.Aggregations;
+using DHT.Server.Data.Filters;
+using DHT.Server.Database;
+using DHT.Server.Download;
+using DHT.Utils.Models;
+using DHT.Utils.Tasks;
+
+namespace DHT.Desktop.Main.Pages;
+
+sealed class AttachmentsPageModel : BaseModel, IDisposable {
+	private static readonly DownloadItemFilter EnqueuedItemFilter = new() {
+		IncludeStatuses = new HashSet<DownloadStatus> {
+			DownloadStatus.Enqueued
+		}
+	};
+
+	private bool isThreadDownloadButtonEnabled = true;
+
+	public string ToggleDownloadButtonText => downloadThread == null ? "Start Downloading" : "Stop Downloading";
+
+	public bool IsToggleDownloadButtonEnabled {
+		get => isThreadDownloadButtonEnabled;
+		set => Change(ref isThreadDownloadButtonEnabled, value);
+	}
+
+	public string DownloadMessage { get; set; } = "";
+	public double DownloadProgress => allItemsCount is null or 0 ? 0.0 : 100.0 * doneItemsCount / allItemsCount.Value;
+
+	public AttachmentFilterPanelModel FilterModel { get; }
+
+	private readonly StatisticsRow statisticsEnqueued = new ("Enqueued");
+	private readonly StatisticsRow statisticsDownloaded = new ("Downloaded");
+	private readonly StatisticsRow statisticsFailed = new ("Failed");
+	private readonly StatisticsRow statisticsSkipped = new ("Skipped");
+
+	public List<StatisticsRow> StatisticsRows {
+		get {
+			return new List<StatisticsRow> {
+				statisticsEnqueued,
+				statisticsDownloaded,
+				statisticsFailed,
+				statisticsSkipped
+			};
+		}
+	}
+
+	public bool IsDownloading => downloadThread != null;
+	public bool HasFailedDownloads => statisticsFailed.Items > 0;
+
+	private readonly IDatabaseFile db;
+	private readonly AsyncValueComputer<DownloadStatusStatistics>.Single downloadStatisticsComputer;
+	private BackgroundDownloadThread? downloadThread;
+
+	private int doneItemsCount;
+	private int? allItemsCount;
+
+	public AttachmentsPageModel() : this(DummyDatabaseFile.Instance) {}
+
+	public AttachmentsPageModel(IDatabaseFile db) {
+		this.db = db;
+		this.FilterModel = new AttachmentFilterPanelModel(db);
+
+		this.downloadStatisticsComputer = AsyncValueComputer<DownloadStatusStatistics>.WithResultProcessor(UpdateStatistics).WithOutdatedResults().BuildWithComputer(db.GetDownloadStatusStatistics);
+		this.downloadStatisticsComputer.Recompute();
+
+		db.Statistics.PropertyChanged += OnDbStatisticsChanged;
+	}
+
+	public void Dispose() {
+		db.Statistics.PropertyChanged -= OnDbStatisticsChanged;
+
+		FilterModel.Dispose();
+		DisposeDownloadThread();
+	}
+
+	private void OnDbStatisticsChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName == nameof(DatabaseStatistics.TotalAttachments)) {
+			if (IsDownloading) {
+				EnqueueDownloadItems();
+			}
+			else {
+				downloadStatisticsComputer.Recompute();
+			}
+		}
+		else if (e.PropertyName == nameof(DatabaseStatistics.TotalDownloads)) {
+			downloadStatisticsComputer.Recompute();
+		}
+	}
+
+	private void EnqueueDownloadItems() {
+		var filter = FilterModel.CreateFilter();
+		filter.DownloadItemRule = AttachmentFilter.DownloadItemRules.OnlyNotPresent;
+		db.EnqueueDownloadItems(filter);
+
+		downloadStatisticsComputer.Recompute();
+	}
+
+	private void UpdateStatistics(DownloadStatusStatistics statusStatistics) {
+		var hadFailedDownloads = HasFailedDownloads;
+
+		statisticsEnqueued.Items = statusStatistics.EnqueuedCount;
+		statisticsEnqueued.Size = statusStatistics.EnqueuedSize;
+
+		statisticsDownloaded.Items = statusStatistics.SuccessfulCount;
+		statisticsDownloaded.Size = statusStatistics.SuccessfulSize;
+
+		statisticsFailed.Items = statusStatistics.FailedCount;
+		statisticsFailed.Size = statusStatistics.FailedSize;
+
+		statisticsSkipped.Items = statusStatistics.SkippedCount;
+		statisticsSkipped.Size = statusStatistics.SkippedSize;
+
+		OnPropertyChanged(nameof(StatisticsRows));
+
+		if (hadFailedDownloads != HasFailedDownloads) {
+			OnPropertyChanged(nameof(HasFailedDownloads));
+		}
+
+		allItemsCount = doneItemsCount + statisticsEnqueued.Items;
+		UpdateDownloadMessage();
+	}
+
+	private void UpdateDownloadMessage() {
+		DownloadMessage = IsDownloading ? doneItemsCount.Format() + " / " + (allItemsCount?.Format() ?? "?") : "";
+
+		OnPropertyChanged(nameof(DownloadMessage));
+		OnPropertyChanged(nameof(DownloadProgress));
+	}
+
+	private void DownloadThreadOnOnItemFinished(object? sender, DownloadItem e) {
+		Interlocked.Increment(ref doneItemsCount);
+
+		Dispatcher.UIThread.Invoke(UpdateDownloadMessage);
+		downloadStatisticsComputer.Recompute();
+	}
+
+	private void DownloadThreadOnOnServerStopped(object? sender, EventArgs e) {
+		downloadStatisticsComputer.Recompute();
+		IsToggleDownloadButtonEnabled = true;
+	}
+
+	public void OnClickToggleDownload() {
+		if (downloadThread == null) {
+			EnqueueDownloadItems();
+			downloadThread = new BackgroundDownloadThread(db);
+			downloadThread.OnItemFinished += DownloadThreadOnOnItemFinished;
+			downloadThread.OnServerStopped += DownloadThreadOnOnServerStopped;
+		}
+		else {
+			IsToggleDownloadButtonEnabled = false;
+			DisposeDownloadThread();
+
+			db.RemoveDownloadItems(EnqueuedItemFilter, FilterRemovalMode.RemoveMatching);
+
+			doneItemsCount = 0;
+			allItemsCount = null;
+			UpdateDownloadMessage();
+		}
+
+		OnPropertyChanged(nameof(ToggleDownloadButtonText));
+		OnPropertyChanged(nameof(IsDownloading));
+	}
+
+	public void OnClickRetryFailedDownloads() {
+		var allExceptFailedFilter = new DownloadItemFilter {
+			IncludeStatuses = new HashSet<DownloadStatus> {
+				DownloadStatus.Enqueued,
+				DownloadStatus.Success
+			}
+		};
+
+		db.RemoveDownloadItems(allExceptFailedFilter, FilterRemovalMode.KeepMatching);
+
+		if (IsDownloading) {
+			EnqueueDownloadItems();
+		}
+	}
+
+	private void DisposeDownloadThread() {
+		if (downloadThread != null) {
+			downloadThread.OnItemFinished -= DownloadThreadOnOnItemFinished;
+			downloadThread.StopThread();
+		}
+
+		downloadThread = null;
+	}
+
+	public sealed class StatisticsRow {
+		public string State { get; }
+		public int Items { get; set; }
+		public ulong? Size { get; set; }
+
+		public StatisticsRow(string state) {
+			State = state;
+		}
+	}
+}

app/Desktop/Main/Pages/DatabasePage.axaml

@@ -24,6 +24,7 @@
         <WrapPanel>
             <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>
     </StackPanel>
 

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

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Pages {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class DatabasePage : UserControl {
-		public DatabasePage() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Pages;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class DatabasePage : UserControl {
+	public DatabasePage() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Pages/DatabasePageModel.cs

@@ -1,157 +1,245 @@
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using Avalonia.Controls;
+using Avalonia.Platform.Storage;
+using Avalonia.Threading;
 using DHT.Desktop.Common;
+using DHT.Desktop.Dialogs.File;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Dialogs.Progress;
+using DHT.Desktop.Dialogs.TextBox;
+using DHT.Server.Data;
 using DHT.Server.Database;
+using DHT.Server.Database.Import;
 using DHT.Utils.Logging;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Pages {
-	sealed class DatabasePageModel : BaseModel {
-		private static readonly Log Log = Log.ForType<DatabasePageModel>();
+namespace DHT.Desktop.Main.Pages; 
 
-		public IDatabaseFile Db { get; }
+sealed class DatabasePageModel : BaseModel {
+	private static readonly Log Log = Log.ForType<DatabasePageModel>();
 
-		public event EventHandler? DatabaseClosed;
+	public IDatabaseFile Db { get; }
 
-		private readonly Window window;
+	public event EventHandler? DatabaseClosed;
 
-		[Obsolete("Designer")]
-		public DatabasePageModel() : this(null!, DummyDatabaseFile.Instance) {}
+	private readonly Window window;
 
-		public DatabasePageModel(Window window, IDatabaseFile db) {
-			this.window = window;
-			this.Db = db;
+	[Obsolete("Designer")]
+	public DatabasePageModel() : this(null!, DummyDatabaseFile.Instance) {}
+
+	public DatabasePageModel(Window window, IDatabaseFile db) {
+		this.window = window;
+		this.Db = db;
+	}
+
+	public async void OpenDatabaseFolder() {
+		string file = Db.Path;
+		string? folder = Path.GetDirectoryName(file);
+
+		if (folder == null) {
+			return;
 		}
 
-		public async void OpenDatabaseFolder() {
-			string file = Db.Path;
-			string? folder = Path.GetDirectoryName(file);
+		switch (Environment.OSVersion.Platform) {
+			case PlatformID.Win32NT:
+				Process.Start("explorer.exe", "/select,\"" + file + "\"");
+				break;
 
-			if (folder == null) {
-				return;
-			}
+			case PlatformID.Unix:
+				Process.Start("xdg-open", new string[] { folder });
+				break;
 
-			switch (Environment.OSVersion.Platform) {
-				case PlatformID.Win32NT:
-					Process.Start("explorer.exe", "/select,\"" + file + "\"");
-					break;
+			case PlatformID.MacOSX:
+				Process.Start("open", new string[] { folder });
+				break;
 
-				case PlatformID.Unix:
-					Process.Start("xdg-open", new string[] { folder });
-					break;
-
-				case PlatformID.MacOSX:
-					Process.Start("open", new string[] { folder });
-					break;
-
-				default:
-					await Dialog.ShowOk(window, "Feature Not Supported", "This feature is not supported for your operating system.");
-					break;
-			}
-		}
-
-		public async void MergeWithDatabase() {
-			var fileDialog = DatabaseGui.NewOpenDatabaseFileDialog();
-			fileDialog.Directory = Path.GetDirectoryName(Db.Path);
-			fileDialog.AllowMultiple = true;
-
-			string[]? paths = await fileDialog.ShowAsync(window);
-			if (paths == null || paths.Length == 0) {
-				return;
-			}
-
-			ProgressDialog progressDialog = new ProgressDialog();
-			progressDialog.DataContext = new ProgressDialogModel(async callback => await MergeWithDatabaseFromPaths(Db, paths, progressDialog, callback)) {
-				Title = "Database Merge"
-			};
-
-			await progressDialog.ShowDialog(window);
-		}
-
-		public void CloseDatabase() {
-			DatabaseClosed?.Invoke(this, EventArgs.Empty);
-		}
-
-		private static async Task MergeWithDatabaseFromPaths(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback) {
-			int total = paths.Length;
-
-			DialogResult.YesNo? upgradeResult = null;
-
-			async Task<bool> CheckCanUpgradeDatabase() {
-				upgradeResult ??= total > 1
-					                  ? await DatabaseGui.ShowCanUpgradeMultipleDatabaseDialog(dialog)
-					                  : await DatabaseGui.ShowCanUpgradeDatabaseDialog(dialog);
-
-				return DialogResult.YesNo.Yes == upgradeResult;
-			}
-
-			var oldStatistics = target.Statistics.Clone();
-			var oldMessageCount = target.CountMessages();
-
-			int successful = 0;
-			int finished = 0;
-
-			foreach (string path in paths) {
-				await callback.Update(Path.GetFileName(path), finished, total);
-				++finished;
-
-				if (!File.Exists(path)) {
-					await Dialog.ShowOk(dialog, "Database Error", "Database '" + Path.GetFileName(path) + "' no longer exists.");
-					continue;
-				}
-
-				IDatabaseFile? db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, dialog, CheckCanUpgradeDatabase);
-				if (db == null) {
-					continue;
-				}
-
-				try {
-					target.AddFrom(db);
-				} catch (Exception ex) {
-					Log.Error(ex);
-					await Dialog.ShowOk(dialog, "Database Error", "Database '" + Path.GetFileName(path) + "' could not be merged: " + ex.Message);
-					continue;
-				} finally {
-					db.Dispose();
-				}
-
-				++successful;
-			}
-
-			await callback.Update("Done", finished, total);
-
-			if (successful == 0) {
-				await Dialog.ShowOk(dialog, "Database Merge", "Nothing was merged.");
-				return;
-			}
-
-			var newStatistics = target.Statistics;
-			long newServers = newStatistics.TotalServers - oldStatistics.TotalServers;
-			long newChannels = newStatistics.TotalChannels - oldStatistics.TotalChannels;
-			long newMessages = target.CountMessages() - oldMessageCount;
-
-			StringBuilder message = new StringBuilder();
-			message.Append("Processed ");
-
-			if (successful == total) {
-				message.Append(successful.Pluralize("database file"));
-			}
-			else {
-				message.Append(successful.Format()).Append(" out of ").Append(total.Pluralize("database file"));
-			}
-
-			message.Append(" and added:\n\n  \u2022 ");
-			message.Append(newServers.Pluralize("server")).Append("\n  \u2022 ");
-			message.Append(newChannels.Pluralize("channel")).Append("\n  \u2022 ");
-			message.Append(newMessages.Pluralize("message"));
-
-			await Dialog.ShowOk(dialog, "Database Merge", message.ToString());
+			default:
+				await Dialog.ShowOk(window, "Feature Not Supported", "This feature is not supported for your operating system.");
+				break;
 		}
 	}
+
+	public void CloseDatabase() {
+		DatabaseClosed?.Invoke(this, EventArgs.Empty);
+	}
+
+	public async void MergeWithDatabase() {
+		var paths = await DatabaseGui.NewOpenDatabaseFilesDialog(window, Path.GetDirectoryName(Db.Path));
+		if (paths.Length == 0) {
+			return;
+		}
+
+		ProgressDialog progressDialog = new ProgressDialog();
+		progressDialog.DataContext = new ProgressDialogModel(async callback => await MergeWithDatabaseFromPaths(Db, paths, progressDialog, callback)) {
+			Title = "Database Merge"
+		};
+
+		await progressDialog.ShowDialog(window);
+	}
+
+	private static async Task MergeWithDatabaseFromPaths(IDatabaseFile target, string[] paths, ProgressDialog dialog, IProgressCallback callback) {
+		int total = paths.Length;
+
+		DialogResult.YesNo? upgradeResult = null;
+
+		async Task<bool> CheckCanUpgradeDatabase() {
+			upgradeResult ??= total > 1
+				                  ? await DatabaseGui.ShowCanUpgradeMultipleDatabaseDialog(dialog)
+				                  : await DatabaseGui.ShowCanUpgradeDatabaseDialog(dialog);
+
+			return DialogResult.YesNo.Yes == upgradeResult;
+		}
+
+		await PerformImport(target, paths, dialog, callback, "Database Merge", "Database Error", "database file", async path => {
+			SynchronizationContext? prevSyncContext = SynchronizationContext.Current;
+			SynchronizationContext.SetSynchronizationContext(new AvaloniaSynchronizationContext());
+			IDatabaseFile? db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, dialog, CheckCanUpgradeDatabase);
+			SynchronizationContext.SetSynchronizationContext(prevSyncContext);
+
+			if (db == null) {
+				return false;
+			}
+
+			try {
+				target.AddFrom(db);
+				return true;
+			} finally {
+				db.Dispose();
+			}
+		});
+	}
+
+	public async void ImportLegacyArchive() {
+		var paths = await window.StorageProvider.OpenFiles(new FilePickerOpenOptions {
+			Title = "Open Legacy DHT Archive",
+			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, Path.GetDirectoryName(Db.Path)),
+			AllowMultiple = true
+		});
+			
+		if (paths.Length == 0) {
+			return;
+		}
+
+		ProgressDialog progressDialog = new ProgressDialog();
+		progressDialog.DataContext = new ProgressDialogModel(async callback => await ImportLegacyArchiveFromPaths(Db, paths, progressDialog, callback)) {
+			Title = "Legacy Archive Import"
+		};
+
+		await progressDialog.ShowDialog(window);
+	}
+
+	private static async Task 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 => {
+			await using var jsonStream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read);
+				
+			return await LegacyArchiveImport.Read(jsonStream, target, fakeSnowflake, async servers => {
+				SynchronizationContext? prevSyncContext = SynchronizationContext.Current;
+				SynchronizationContext.SetSynchronizationContext(new AvaloniaSynchronizationContext());
+				Dictionary<DHT.Server.Data.Server, ulong>? result = await Dispatcher.UIThread.InvokeAsync(() => AskForServerIds(dialog, servers));
+				SynchronizationContext.SetSynchronizationContext(prevSyncContext);
+				return result;
+			});
+		});
+	}
+
+	private static async Task<Dictionary<DHT.Server.Data.Server, ulong>?> AskForServerIds(Window window, DHT.Server.Data.Server[] servers) {
+		static bool IsValidSnowflake(string value) {
+			return string.IsNullOrEmpty(value) || ulong.TryParse(value, out _);
+		}
+			
+		var items = new List<TextBoxItem<DHT.Server.Data.Server>>();
+
+		foreach (var 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
+			});
+		}
+
+		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."
+		};
+
+		var dialog = new TextBoxDialog { DataContext = model };
+		var result = await dialog.ShowDialog<DialogResult.OkCancel>(window);
+
+		if (result != DialogResult.OkCancel.Ok) {
+			return null;
+		}
+
+		return model.ValidItems
+		            .Where(static item => !string.IsNullOrEmpty(item.Value))
+		            .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) {
+		int total = paths.Length;
+		var oldStatistics = target.SnapshotStatistics();
+
+		int successful = 0;
+		int finished = 0;
+
+		foreach (string path in paths) {
+			await callback.Update(Path.GetFileName(path), finished, total);
+			++finished;
+
+			if (!File.Exists(path)) {
+				await Dialog.ShowOk(dialog, errorDialogTitle, "File '" + Path.GetFileName(path) + "' no longer exists.");
+				continue;
+			}
+
+			try {
+				if (await performImport(path)) {
+					++successful;
+				}
+			} catch (Exception ex) {
+				Log.Error(ex);
+				await Dialog.ShowOk(dialog, errorDialogTitle, "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;
+		}
+
+		await Dialog.ShowOk(dialog, neutralDialogTitle, GetImportDialogMessage(oldStatistics, target.SnapshotStatistics(), successful, total, itemName));
+	}
+
+	private static string GetImportDialogMessage(DatabaseStatisticsSnapshot oldStatistics, DatabaseStatisticsSnapshot newStatistics, int successfulItems, int totalItems, string itemName) {
+		long newServers = newStatistics.TotalServers - oldStatistics.TotalServers;
+		long newChannels = newStatistics.TotalChannels - oldStatistics.TotalChannels;
+		long newUsers = newStatistics.TotalUsers - oldStatistics.TotalUsers;
+		long newMessages = newStatistics.TotalMessages - oldStatistics.TotalMessages;
+
+		StringBuilder message = new StringBuilder();
+		message.Append("Processed ");
+
+		if (successfulItems == totalItems) {
+			message.Append(successfulItems.Pluralize(itemName));
+		}
+		else {
+			message.Append(successfulItems.Format()).Append(" out of ").Append(totalItems.Pluralize(itemName));
+		}
+
+		message.Append(" and added:\n\n  \u2022 ");
+		message.Append(newServers.Pluralize("server")).Append("\n  \u2022 ");
+		message.Append(newChannels.Pluralize("channel")).Append("\n  \u2022 ");
+		message.Append(newUsers.Pluralize("user")).Append("\n  \u2022 ");
+		message.Append(newMessages.Pluralize("message"));
+
+		return message.ToString();
+	}
 }

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

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Pages {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class DebugPage : UserControl {
-		public DebugPage() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Pages;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class DebugPage : UserControl {
+	public DebugPage() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Pages/DebugPageModel.cs

@@ -52,9 +52,9 @@ namespace DHT.Desktop.Main.Pages {
 
 			await progressDialog.ShowDialog(window);
 		}
-		
+
 		private const int BatchSize = 500;
-		
+
 		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);
@@ -63,7 +63,7 @@ namespace DHT.Desktop.Main.Pages {
 			var server = new DHT.Server.Data.Server {
 				Id = RandomId(rand),
 				Name = RandomName("s"),
-				Type = ServerType.Server
+				Type = ServerType.Server,
 			};
 
 			var channels = Enumerable.Range(0, channelCount).Select(i => new Channel {
@@ -73,36 +73,36 @@ namespace DHT.Desktop.Main.Pages {
 				ParentId = null,
 				Position = i,
 				Topic = RandomText(rand, 10),
-				Nsfw = rand.Next(4) == 0
+				Nsfw = rand.Next(4) == 0,
 			}).ToArray();
-			
+
 			var users = Enumerable.Range(0, userCount).Select(_ => new User {
 				Id = RandomId(rand),
 				Name = RandomName("u"),
 				AvatarUrl = null,
-				Discriminator = rand.Next(0, 9999).ToString()
+				Discriminator = rand.Next(0, 9999).ToString(),
 			}).ToArray();
-			
+
 			db.AddServer(server);
 			db.AddUsers(users);
-			
+
 			foreach (var channel in channels) {
 				db.AddChannel(channel);
 			}
-			
+
 			var now = DateTimeOffset.Now;
 			int batchIndex = 0;
-			
+
 			while (messageCount > 0) {
 				int hourOffset = batchIndex;
-				
+
 				var messages = Enumerable.Range(0, Math.Min(messageCount, BatchSize)).Select(i => {
-					DateTimeOffset time = now.AddHours(hourOffset).AddMinutes((i * 60.0) / BatchSize);
+					DateTimeOffset time = now.AddHours(hourOffset).AddMinutes(i * 60.0 / BatchSize);
 					DateTimeOffset? edit = rand.Next(100) == 0 ? time.AddSeconds(rand.Next(1, 60)) : null;
 
 					var timeMillis = time.ToUnixTimeMilliseconds();
 					var editMillis = edit?.ToUnixTimeMilliseconds();
-					
+
 					return new Message {
 						Id = (ulong) timeMillis,
 						Sender = RandomBiasedIndex(rand, users).Id,
@@ -113,12 +113,12 @@ namespace DHT.Desktop.Main.Pages {
 						RepliedToId = null,
 						Attachments = ImmutableArray<Attachment>.Empty,
 						Embeds = ImmutableArray<Embed>.Empty,
-						Reactions = ImmutableArray<Reaction>.Empty
+						Reactions = ImmutableArray<Reaction>.Empty,
 					};
 				}).ToArray();
-				
+
 				db.AddMessages(messages);
-				
+
 				messageCount -= BatchSize;
 				await callback.Update("Adding messages in batches of " + BatchSize, ++batchIndex, batchCount);
 			}
@@ -161,9 +161,9 @@ namespace DHT.Desktop.Main.Pages {
 			"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));
 			return string.Join(' ', Enumerable.Range(0, wordCount).Select(_ => RandomWords[rand.Next(RandomWords.Length)]));

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

@@ -3,35 +3,29 @@ using System.Diagnostics.CodeAnalysis;
 using System.Threading.Tasks;
 using Avalonia.Controls;
 using Avalonia.Interactivity;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Pages {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class TrackingPage : UserControl {
-		private bool isCopyingScript;
+namespace DHT.Desktop.Main.Pages;
 
-		public TrackingPage() {
-			InitializeComponent();
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class TrackingPage : UserControl {
+	private bool isCopyingScript;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+	public TrackingPage() {
+		InitializeComponent();
+	}
 
-		public async void CopyTrackingScriptButton_OnClick(object? sender, RoutedEventArgs e) {
-			if (DataContext is TrackingPageModel model) {
-				var button = this.FindControl<Button>("CopyTrackingScript");
-				var originalText = button.Content;
-				button.MinWidth = button.Bounds.Width;
+	public async void CopyTrackingScriptButton_OnClick(object? sender, RoutedEventArgs e) {
+		if (DataContext is TrackingPageModel model) {
+			var originalText = CopyTrackingScript.Content;
+			CopyTrackingScript.MinWidth = CopyTrackingScript.Bounds.Width;
 
-				if (await model.OnClickCopyTrackingScript() && !isCopyingScript) {
-					isCopyingScript = true;
-					button.Content = "Script Copied!";
+			if (await model.OnClickCopyTrackingScript() && !isCopyingScript) {
+				isCopyingScript = true;
+				CopyTrackingScript.Content = "Script Copied!";
 
-					await Task.Delay(TimeSpan.FromSeconds(2));
-					button.Content = originalText;
-					isCopyingScript = false;
-				}
+				await Task.Delay(TimeSpan.FromSeconds(2));
+				CopyTrackingScript.Content = originalText;
+				isCopyingScript = false;
 			}
 		}
 	}

app/Desktop/Main/Pages/TrackingPageModel.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Threading.Tasks;
 using System.Web;
-using Avalonia;
 using Avalonia.Controls;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Discord;
@@ -9,109 +8,109 @@ using DHT.Desktop.Server;
 using DHT.Utils.Models;
 using static DHT.Desktop.Program;
 
-namespace DHT.Desktop.Main.Pages {
-	sealed class TrackingPageModel : BaseModel {
-		private bool areDevToolsEnabled;
+namespace DHT.Desktop.Main.Pages;
 
-		private bool AreDevToolsEnabled {
-			get => areDevToolsEnabled;
-			set {
-				Change(ref areDevToolsEnabled, value);
-				OnPropertyChanged(nameof(ToggleAppDevToolsButtonText));
+sealed class TrackingPageModel : BaseModel {
+	private bool areDevToolsEnabled;
+
+	private bool AreDevToolsEnabled {
+		get => areDevToolsEnabled;
+		set {
+			Change(ref areDevToolsEnabled, value);
+			OnPropertyChanged(nameof(ToggleAppDevToolsButtonText));
+		}
+	}
+
+	public bool IsToggleAppDevToolsButtonEnabled { get; private set; } = true;
+
+	public string ToggleAppDevToolsButtonText {
+		get {
+			if (!IsToggleAppDevToolsButtonEnabled) {
+				return "Unavailable";
 			}
+
+			return AreDevToolsEnabled ? "Disable Ctrl+Shift+I" : "Enable Ctrl+Shift+I";
+		}
+	}
+
+	private readonly Window window;
+
+	[Obsolete("Designer")]
+	public TrackingPageModel() : this(null!) {}
+
+	public TrackingPageModel(Window window) {
+		this.window = window;
+	}
+
+	public async Task Initialize() {
+		bool? devToolsEnabled = await DiscordAppSettings.AreDevToolsEnabled();
+		if (devToolsEnabled.HasValue) {
+			AreDevToolsEnabled = devToolsEnabled.Value;
+		}
+		else {
+			IsToggleAppDevToolsButtonEnabled = false;
+			OnPropertyChanged(nameof(IsToggleAppDevToolsButtonEnabled));
+		}
+	}
+
+	public async Task<bool> OnClickCopyTrackingScript() {
+		string bootstrap = await Resources.ReadTextAsync("Tracker/bootstrap.js");
+		string script = bootstrap.Replace("= 0; /*[PORT]*/", "= " + ServerManager.Port + ";")
+		                         .Replace("/*[TOKEN]*/", HttpUtility.JavaScriptStringEncode(ServerManager.Token))
+		                         .Replace("/*[IMPORTS]*/", await Resources.ReadJoinedAsync("Tracker/scripts/", '\n'))
+		                         .Replace("/*[CSS-CONTROLLER]*/", await Resources.ReadTextAsync("Tracker/styles/controller.css"))
+		                         .Replace("/*[CSS-SETTINGS]*/", await Resources.ReadTextAsync("Tracker/styles/settings.css"));
+
+		var clipboard = window.Clipboard;
+		if (clipboard == null) {
+			await Dialog.ShowOk(window, "Copy Tracking Script", "Clipboard is not available on this system.");
+			return false;
 		}
 
-		public bool IsToggleAppDevToolsButtonEnabled { get; private set; } = true;
-
-		public string ToggleAppDevToolsButtonText {
-			get {
-				if (!IsToggleAppDevToolsButtonEnabled) {
-					return "Unavailable";
-				}
-
-				return AreDevToolsEnabled ? "Disable Ctrl+Shift+I" : "Enable Ctrl+Shift+I";
-			}
+		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 readonly Window window;
+	public async void OnClickToggleAppDevTools() {
+		const string DialogTitle = "Discord App Settings File";
 
-		[Obsolete("Designer")]
-		public TrackingPageModel() : this(null!) {}
+		bool oldState = AreDevToolsEnabled;
+		bool newState = !oldState;
 
-		public TrackingPageModel(Window window) {
-			this.window = window;
-		}
+		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.");
+				break;
 
-		public async Task Initialize() {
-			bool? devToolsEnabled = await DiscordAppSettings.AreDevToolsEnabled();
-			if (devToolsEnabled.HasValue) {
-				AreDevToolsEnabled = devToolsEnabled.Value;
-			}
-			else {
-				IsToggleAppDevToolsButtonEnabled = false;
-				OnPropertyChanged(nameof(IsToggleAppDevToolsButtonEnabled));
-			}
-		}
+			case SettingsJsonResult.AlreadySet:
+				await Dialog.ShowOk(window, DialogTitle, "Ctrl+Shift+I is already " + (newState ? "enabled." : "disabled."));
+				AreDevToolsEnabled = newState;
+				break;
 
-		public async Task<bool> OnClickCopyTrackingScript() {
-			string bootstrap = await Resources.ReadTextAsync("Tracker/bootstrap.js");
-			string script = bootstrap.Replace("= 0; /*[PORT]*/", "= " + ServerManager.Port + ";")
-			                         .Replace("/*[TOKEN]*/", HttpUtility.JavaScriptStringEncode(ServerManager.Token))
-			                         .Replace("/*[IMPORTS]*/", await Resources.ReadJoinedAsync("Tracker/scripts/", '\n'))
-			                         .Replace("/*[CSS-CONTROLLER]*/", await Resources.ReadTextAsync("Tracker/styles/controller.css"))
-			                         .Replace("/*[CSS-SETTINGS]*/", await Resources.ReadTextAsync("Tracker/styles/settings.css"));
+			case SettingsJsonResult.FileNotFound:
+				await Dialog.ShowOk(window, DialogTitle, "Cannot find the settings file:\n" + DiscordAppSettings.JsonFilePath);
+				break;
 
-			var clipboard = Application.Current?.Clipboard;
-			if (clipboard == null) {
-				await Dialog.ShowOk(window, "Copy Tracking Script", "Clipboard is not available on this system.");
-				return false;
-			}
+			case SettingsJsonResult.ReadError:
+				await Dialog.ShowOk(window, DialogTitle, "Cannot read the settings file:\n" + DiscordAppSettings.JsonFilePath);
+				break;
 
-			try {
-				await clipboard.SetTextAsync(script);
-				return true;
-			} catch {
-				await Dialog.ShowOk(window, "Copy Tracking Script", "An error occurred while copying to clipboard.");
-				return false;
-			}
-		}
+			case SettingsJsonResult.InvalidJson:
+				await Dialog.ShowOk(window, DialogTitle, "Unknown format of the settings file:\n" + DiscordAppSettings.JsonFilePath);
+				break;
 
-		public async void OnClickToggleAppDevTools() {
-			const string DialogTitle = "Discord App Settings File";
+			case SettingsJsonResult.WriteError:
+				await Dialog.ShowOk(window, DialogTitle, "Cannot save the settings file:\n" + DiscordAppSettings.JsonFilePath);
+				break;
 
-			bool oldState = AreDevToolsEnabled;
-			bool newState = !oldState;
-
-			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.");
-					break;
-
-				case SettingsJsonResult.AlreadySet:
-					await Dialog.ShowOk(window, DialogTitle, "Ctrl+Shift+I is already " + (newState ? "enabled." : "disabled."));
-					AreDevToolsEnabled = newState;
-					break;
-
-				case SettingsJsonResult.FileNotFound:
-					await Dialog.ShowOk(window, DialogTitle, "Cannot find the settings file:\n" + DiscordAppSettings.JsonFilePath);
-					break;
-
-				case SettingsJsonResult.ReadError:
-					await Dialog.ShowOk(window, DialogTitle, "Cannot read the settings file:\n" + DiscordAppSettings.JsonFilePath);
-					break;
-
-				case SettingsJsonResult.InvalidJson:
-					await Dialog.ShowOk(window, DialogTitle, "Unknown format of the settings file:\n" + DiscordAppSettings.JsonFilePath);
-					break;
-
-				case SettingsJsonResult.WriteError:
-					await Dialog.ShowOk(window, DialogTitle, "Cannot save the settings file:\n" + DiscordAppSettings.JsonFilePath);
-					break;
-
-				default:
-					throw new ArgumentOutOfRangeException();
-			}
+			default:
+				throw new ArgumentOutOfRangeException();
 		}
 	}
 }

app/Desktop/Main/Pages/ViewerPage.axaml

@@ -5,9 +5,7 @@
              xmlns:pages="clr-namespace:DHT.Desktop.Main.Pages"
              xmlns:controls="clr-namespace:DHT.Desktop.Main.Controls"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="DHT.Desktop.Main.Pages.ViewerPage"
-             AttachedToVisualTree="OnAttachedToVisualTree"
-             DetachedFromVisualTree="OnDetachedFromVisualTree">
+             x:Class="DHT.Desktop.Main.Pages.ViewerPage">
 
     <Design.DataContext>
         <pages:ViewerPageModel />
@@ -15,17 +13,16 @@
 
     <UserControl.Styles>
         <Style Selector="Expander">
-            <Setter Property="Margin" Value="0 25 0 0" />
+            <Setter Property="Margin" Value="0 5 0 0" />
         </Style>
     </UserControl.Styles>
 
-    <StackPanel Orientation="Vertical">
+    <StackPanel Orientation="Vertical" Spacing="20">
         <StackPanel Orientation="Horizontal" VerticalAlignment="Top">
             <Button Command="{Binding OnClickOpenViewer}" Margin="0 0 5 0">Open Viewer</Button>
             <Button Command="{Binding OnClickSaveViewer}" Margin="5 0 0 0">Save Viewer</Button>
         </StackPanel>
-        <TextBlock Text="{Binding ExportedMessageText}" Margin="0 20 0 0" />
-        <controls:FilterPanel DataContext="{Binding FilterModel}" />
+        <controls:MessageFilterPanel DataContext="{Binding FilterModel}" />
         <Expander Header="Database Tools">
             <StackPanel Orientation="Vertical" Spacing="10">
                 <StackPanel Orientation="Vertical" Spacing="4">

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

@@ -1,29 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
-using Avalonia;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Pages {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class ViewerPage : UserControl {
-		public ViewerPage() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Pages;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
-
-		public void OnAttachedToVisualTree(object? sender, VisualTreeAttachmentEventArgs e) {
-			if (DataContext is ViewerPageModel model) {
-				model.SetPageVisible(true);
-			}
-		}
-
-		public void OnDetachedFromVisualTree(object? sender, VisualTreeAttachmentEventArgs e) {
-			if (DataContext is ViewerPageModel model) {
-				model.SetPageVisible(false);
-			}
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class ViewerPage : UserControl {
+	public ViewerPage() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Pages/ViewerPageModel.cs

@@ -1,143 +1,148 @@
 using System;
-using System.Collections.Generic;
+using System.Collections.Concurrent;
 using System.ComponentModel;
 using System.Diagnostics;
 using System.IO;
+using System.Text;
 using System.Threading.Tasks;
 using System.Web;
 using Avalonia.Controls;
+using Avalonia.Platform.Storage;
 using DHT.Desktop.Common;
+using DHT.Desktop.Dialogs.File;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Main.Controls;
+using DHT.Desktop.Server;
 using DHT.Server.Data.Filters;
 using DHT.Server.Database;
 using DHT.Server.Database.Export;
+using DHT.Server.Database.Export.Strategy;
 using DHT.Utils.Models;
 using static DHT.Desktop.Program;
 
-namespace DHT.Desktop.Main.Pages {
-	sealed class ViewerPageModel : BaseModel, IDisposable {
-		public string ExportedMessageText { get; private set; } = "";
+namespace DHT.Desktop.Main.Pages;
 
-		public bool DatabaseToolFilterModeKeep { get; set; } = true;
-		public bool DatabaseToolFilterModeRemove { get; set; } = false;
+sealed class ViewerPageModel : BaseModel, IDisposable {
+	public static readonly ConcurrentBag<string> TemporaryFiles = new ();
 
-		private bool hasFilters = false;
+	public bool DatabaseToolFilterModeKeep { get; set; } = true;
+	public bool DatabaseToolFilterModeRemove { get; set; } = false;
 
-		public bool HasFilters {
-			get => hasFilters;
-			set => Change(ref hasFilters, value);
-		}
+	private bool hasFilters = false;
 
-		private FilterPanelModel FilterModel { get; }
+	public bool HasFilters {
+		get => hasFilters;
+		set => Change(ref hasFilters, value);
+	}
 
-		private readonly Window window;
-		private readonly IDatabaseFile db;
+	private MessageFilterPanelModel FilterModel { get; }
 
-		private bool isPageVisible = false;
+	private readonly Window window;
+	private readonly IDatabaseFile db;
 
-		[Obsolete("Designer")]
-		public ViewerPageModel() : this(null!, DummyDatabaseFile.Instance) {}
+	[Obsolete("Designer")]
+	public ViewerPageModel() : this(null!, DummyDatabaseFile.Instance) {}
 
-		public ViewerPageModel(Window window, IDatabaseFile db) {
-			this.window = window;
-			this.db = db;
+	public ViewerPageModel(Window window, IDatabaseFile db) {
+		this.window = window;
+		this.db = db;
 
-			FilterModel = new FilterPanelModel(window, db);
-			FilterModel.FilterPropertyChanged += OnFilterPropertyChanged;
-			db.Statistics.PropertyChanged += OnDbStatisticsChanged;
-		}
+		FilterModel = new MessageFilterPanelModel(window, db, "Will export");
+		FilterModel.FilterPropertyChanged += OnFilterPropertyChanged;
+	}
 
-		public void Dispose() {
-			db.Statistics.PropertyChanged -= OnDbStatisticsChanged;
-			FilterModel.Dispose();
-		}
+	public void Dispose() {
+		FilterModel.Dispose();
+	}
 
-		public void SetPageVisible(bool isPageVisible) {
-			this.isPageVisible = isPageVisible;
-			if (isPageVisible) {
-				UpdateStatistics();
-			}
-		}
+	private void OnFilterPropertyChanged(object? sender, PropertyChangedEventArgs e) {
+		HasFilters = FilterModel.HasAnyFilters;
+	}
 
-		private void OnFilterPropertyChanged(object? sender, PropertyChangedEventArgs e) {
-			UpdateStatistics();
-			HasFilters = FilterModel.HasAnyFilters;
-		}
+	private async Task WriteViewerFile(string path, IViewerExportStrategy strategy) {
+		const string ArchiveTag = "/*[ARCHIVE]*/";
 
-		private void OnDbStatisticsChanged(object? sender, PropertyChangedEventArgs e) {
-			if (isPageVisible && e.PropertyName == nameof(DatabaseStatistics.TotalMessages)) {
-				UpdateStatistics();
-			}
-		}
+		string indexFile = await Resources.ReadTextAsync("Viewer/index.html");
+		string viewerTemplate = indexFile.Replace("/*[JS]*/", await Resources.ReadJoinedAsync("Viewer/scripts/", '\n'))
+		                                 .Replace("/*[CSS]*/", await Resources.ReadJoinedAsync("Viewer/styles/", '\n'));
 
-		private void UpdateStatistics() {
-			var filter = FilterModel.CreateFilter();
-			var allMessagesCount = db.Statistics.TotalMessages?.Format() ?? "?";
-			var filteredMessagesCount = filter.IsEmpty ? allMessagesCount : db.CountMessages(filter).Format();
+		int viewerArchiveTagStart = viewerTemplate.IndexOf(ArchiveTag);
+		int viewerArchiveTagEnd = viewerArchiveTagStart + ArchiveTag.Length;
 
-			ExportedMessageText = "Will export " + filteredMessagesCount + " out of " + allMessagesCount + " message(s).";
-			OnPropertyChanged(nameof(ExportedMessageText));
-		}
+		string jsonTempFile = path + ".tmp";
 
-		private async Task<string> GenerateViewerContents() {
-			string json = ViewerJsonExport.Generate(db, FilterModel.CreateFilter());
+		await using (var jsonStream = new FileStream(jsonTempFile, FileMode.Create, FileAccess.ReadWrite, FileShare.Read)) {
+			await ViewerJsonExport.Generate(jsonStream, strategy, db, FilterModel.CreateFilter());
 
-			string index = await Resources.ReadTextAsync("Viewer/index.html");
-			string viewer = index.Replace("/*[JS]*/", await Resources.ReadJoinedAsync("Viewer/scripts/", '\n'))
-			                     .Replace("/*[CSS]*/", await Resources.ReadJoinedAsync("Viewer/styles/", '\n'))
-			                     .Replace("/*[ARCHIVE]*/", HttpUtility.JavaScriptStringEncode(json));
-			return viewer;
-		}
+			char[] jsonBuffer = new char[Math.Min(32768, jsonStream.Position)];
+			jsonStream.Position = 0;
 
-		public async void OnClickOpenViewer() {
-			string rootPath = Path.Combine(Path.GetTempPath(), "DiscordHistoryTracker");
-			string filenameBase = Path.GetFileNameWithoutExtension(db.Path) + "-" + DateTime.Now.ToString("yyyy-MM-dd");
-			string fullPath = Path.Combine(rootPath, filenameBase + ".html");
-			int counter = 0;
+			await using (var outputStream = new FileStream(path, FileMode.Create, FileAccess.Write, FileShare.Read))
+			await using (var outputWriter = new StreamWriter(outputStream, Encoding.UTF8)) {
+				await outputWriter.WriteAsync(viewerTemplate[..viewerArchiveTagStart]);
 
-			while (File.Exists(fullPath)) {
-				++counter;
-				fullPath = Path.Combine(rootPath, filenameBase + "-" + counter + ".html");
-			}
-
-			Directory.CreateDirectory(rootPath);
-			await File.WriteAllTextAsync(fullPath, await GenerateViewerContents());
-
-			Process.Start(new ProcessStartInfo(fullPath) { UseShellExecute = true });
-		}
-
-		public async void OnClickSaveViewer() {
-			var dialog = new SaveFileDialog {
-				Title = "Save Viewer",
-				InitialFileName = "archive.html",
-				Directory = Path.GetDirectoryName(db.Path),
-				Filters = new List<FileDialogFilter> {
-					new() {
-						Name = "Discord History Viewer",
-						Extensions = { "html" }
+				using (var jsonReader = new StreamReader(jsonStream, Encoding.UTF8)) {
+					int readBytes;
+					while ((readBytes = await jsonReader.ReadAsync(jsonBuffer, 0, jsonBuffer.Length)) > 0) {
+						string jsonChunk = new string(jsonBuffer, 0, readBytes);
+						await outputWriter.WriteAsync(HttpUtility.JavaScriptStringEncode(jsonChunk));
 					}
 				}
-			}.ShowAsync(window);
 
-			string? path = await dialog;
-			if (!string.IsNullOrEmpty(path)) {
-				await File.WriteAllTextAsync(path, await GenerateViewerContents());
+				await outputWriter.WriteAsync(viewerTemplate[viewerArchiveTagEnd..]);
 			}
 		}
 
-		public async void OnClickApplyFiltersToDatabase() {
-			var filter = FilterModel.CreateFilter();
+		File.Delete(jsonTempFile);
+	}
 
-			if (DatabaseToolFilterModeKeep) {
-				if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Keep Matching Messages in This Database", db.CountMessages(filter).Pluralize("message") + " will be kept, and the rest will be removed from this database. This action cannot be undone. Proceed?")) {
-					db.RemoveMessages(filter, MessageFilterRemovalMode.KeepMatching);
-				}
+	public async void OnClickOpenViewer() {
+		string rootPath = Path.Combine(Path.GetTempPath(), "DiscordHistoryTracker");
+		string filenameBase = Path.GetFileNameWithoutExtension(db.Path) + "-" + DateTime.Now.ToString("yyyy-MM-dd");
+		string fullPath = Path.Combine(rootPath, filenameBase + ".html");
+		int counter = 0;
+
+		while (File.Exists(fullPath)) {
+			++counter;
+			fullPath = Path.Combine(rootPath, filenameBase + "-" + counter + ".html");
+		}
+
+		TemporaryFiles.Add(fullPath);
+
+		Directory.CreateDirectory(rootPath);
+		await WriteViewerFile(fullPath, new LiveViewerExportStrategy(ServerManager.Port, ServerManager.Token));
+
+		Process.Start(new ProcessStartInfo(fullPath) { UseShellExecute = true });
+	}
+
+	private static readonly FilePickerFileType[] ViewerFileTypes = {
+		FileDialogs.CreateFilter("Discord History Viewer", new string[] { "html" }),
+	};
+	
+	public async void OnClickSaveViewer() {
+		string? path = await window.StorageProvider.SaveFile(new FilePickerSaveOptions {
+			Title = "Save Viewer",
+			FileTypeChoices = ViewerFileTypes,
+			SuggestedFileName = Path.GetFileNameWithoutExtension(db.Path) + ".html",
+			SuggestedStartLocation = await FileDialogs.GetSuggestedStartLocation(window, Path.GetDirectoryName(db.Path)),
+		});
+
+		if (path != null) {
+			await WriteViewerFile(path, StandaloneViewerExportStrategy.Instance);
+		}
+	}
+
+	public async void OnClickApplyFiltersToDatabase() {
+		var filter = FilterModel.CreateFilter();
+
+		if (DatabaseToolFilterModeKeep) {
+			if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Keep Matching Messages in This Database", db.CountMessages(filter).Pluralize("message") + " will be kept, and the rest will be removed from this database. This action cannot be undone. Proceed?")) {
+				db.RemoveMessages(filter, FilterRemovalMode.KeepMatching);
 			}
-			else if (DatabaseToolFilterModeRemove) {
-				if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Remove Matching Messages in This Database", db.CountMessages(filter).Pluralize("message") + " will be removed from this database. This action cannot be undone. Proceed?")) {
-					db.RemoveMessages(filter, MessageFilterRemovalMode.RemoveMatching);
-				}
+		}
+		else if (DatabaseToolFilterModeRemove) {
+			if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Remove Matching Messages in This Database", db.CountMessages(filter).Pluralize("message") + " will be removed from this database. This action cannot be undone. Proceed?")) {
+				db.RemoveMessages(filter, FilterRemovalMode.RemoveMatching);
 			}
 		}
 	}

app/Desktop/Main/Screens/MainContentScreen.axaml

@@ -73,14 +73,14 @@
     <DockPanel>
         <Border Classes="statusBar" DockPanel.Dock="Bottom">
             <DockPanel>
-                <TextBlock Classes="invisibleTabItem" DockPanel.Dock="Left">Advanced</TextBlock>
+                <TextBlock Classes="invisibleTabItem" DockPanel.Dock="Left">Attachments</TextBlock>
                 <controls:StatusBar DataContext="{Binding StatusBarModel}" DockPanel.Dock="Right" />
             </DockPanel>
         </Border>
         <TabControl x:Name="TabControl" TabStripPlacement="Left" DockPanel.Dock="Top">
             <TabControl.ItemsPanel>
                 <ItemsPanelTemplate>
-                    <Grid ColumnDefinitions="Auto" RowDefinitions="Auto,Auto,Auto,*,Auto,Auto" />
+                    <Grid ColumnDefinitions="Auto" RowDefinitions="Auto,Auto,Auto,Auto,*,Auto,Auto" />
                 </ItemsPanelTemplate>
             </TabControl.ItemsPanel>
             <TabItem x:Name="TabDatabase" Header="Database" Classes="first" Grid.Row="0">
@@ -93,17 +93,22 @@
                     <ContentPresenter Content="{Binding TrackingPage}" Classes="page" />
                 </ScrollViewer>
             </TabItem>
-            <TabItem x:Name="TabViewer" Header="Viewer" Grid.Row="2">
+            <TabItem x:Name="TabAttachments" Header="Attachments" Grid.Row="2">
+                <ScrollViewer>
+                    <ContentPresenter Content="{Binding AttachmentsPage}" Classes="page" />
+                </ScrollViewer>
+            </TabItem>
+            <TabItem x:Name="TabViewer" Header="Viewer" Grid.Row="3">
                 <ScrollViewer>
                     <ContentPresenter Content="{Binding ViewerPage}" Classes="page" />
                 </ScrollViewer>
             </TabItem>
-            <TabItem x:Name="TabAdvanced" Header="Advanced" Grid.Row="4">
+            <TabItem x:Name="TabAdvanced" Header="Advanced" Grid.Row="5">
                 <ScrollViewer>
                     <ContentPresenter Content="{Binding AdvancedPage}" Classes="page" />
                 </ScrollViewer>
             </TabItem>
-            <TabItem x:Name="TabDebug" Header="Debug" Grid.Row="5" IsVisible="{Binding HasDebugPage}">
+            <TabItem x:Name="TabDebug" Header="Debug" Grid.Row="6" IsVisible="{Binding HasDebugPage}">
                 <ScrollViewer>
                     <ContentPresenter Content="{Binding DebugPage}" Classes="page" />
                 </ScrollViewer>

app/Desktop/Main/Screens/MainContentScreen.axaml.cs

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Screens {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class MainContentScreen : UserControl {
-		public MainContentScreen() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Screens;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class MainContentScreen : UserControl {
+	public MainContentScreen() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Screens/MainContentScreenModel.cs

@@ -9,104 +9,111 @@ using DHT.Server.Database;
 using DHT.Server.Service;
 using DHT.Utils.Logging;
 
-namespace DHT.Desktop.Main.Screens {
-	sealed class MainContentScreenModel : IDisposable {
-		private static readonly Log Log = Log.ForType<MainContentScreenModel>();
+namespace DHT.Desktop.Main.Screens;
 
-		public DatabasePage DatabasePage { get; }
-		private DatabasePageModel DatabasePageModel { get; }
+sealed class MainContentScreenModel : IDisposable {
+	private static readonly Log Log = Log.ForType<MainContentScreenModel>();
 
-		public TrackingPage TrackingPage { get; }
-		private TrackingPageModel TrackingPageModel { get; }
+	public DatabasePage DatabasePage { get; }
+	private DatabasePageModel DatabasePageModel { get; }
 
-		public ViewerPage ViewerPage { get; }
-		private ViewerPageModel ViewerPageModel { get; }
+	public TrackingPage TrackingPage { get; }
+	private TrackingPageModel TrackingPageModel { get; }
 
-		public AdvancedPage AdvancedPage { get; }
-		private AdvancedPageModel AdvancedPageModel { get; }
+	public AttachmentsPage AttachmentsPage { get; }
+	private AttachmentsPageModel AttachmentsPageModel { get; }
 
-		public DebugPage? DebugPage { get; }
+	public ViewerPage ViewerPage { get; }
+	private ViewerPageModel ViewerPageModel { get; }
 
-		#if DEBUG
-		public bool HasDebugPage => true;
-		private DebugPageModel DebugPageModel { get; }
-		#else
+	public AdvancedPage AdvancedPage { get; }
+	private AdvancedPageModel AdvancedPageModel { get; }
+
+	public DebugPage? DebugPage { get; }
+
+	#if DEBUG
+	public bool HasDebugPage => true;
+	private DebugPageModel DebugPageModel { get; }
+	#else
 		public bool HasDebugPage => false;
-		#endif
+	#endif
 
-		public StatusBarModel StatusBarModel { get; }
+	public StatusBarModel StatusBarModel { get; }
 
-		public event EventHandler? DatabaseClosed {
-			add {
-				DatabasePageModel.DatabaseClosed += value;
-			}
-			remove {
-				DatabasePageModel.DatabaseClosed -= value;
-			}
+	public event EventHandler? DatabaseClosed {
+		add {
+			DatabasePageModel.DatabaseClosed += value;
 		}
-
-		private readonly Window window;
-		private readonly ServerManager serverManager;
-
-		[Obsolete("Designer")]
-		public MainContentScreenModel() : this(null!, DummyDatabaseFile.Instance) {}
-
-		public MainContentScreenModel(Window window, IDatabaseFile db) {
-			this.window = window;
-			this.serverManager = new ServerManager(db);
-
-			ServerLauncher.ServerManagementExceptionCaught += ServerLauncherOnServerManagementExceptionCaught;
-
-			DatabasePageModel = new DatabasePageModel(window, db);
-			DatabasePage = new DatabasePage { DataContext = DatabasePageModel };
-
-			TrackingPageModel = new TrackingPageModel(window);
-			TrackingPage = new TrackingPage { DataContext = TrackingPageModel };
-
-			ViewerPageModel = new ViewerPageModel(window, db);
-			ViewerPage = new ViewerPage { DataContext = ViewerPageModel };
-
-			AdvancedPageModel = new AdvancedPageModel(window, db, serverManager);
-			AdvancedPage = new AdvancedPage { DataContext = AdvancedPageModel };
-
-			#if DEBUG
-			DebugPageModel = new DebugPageModel(window, db);
-			DebugPage = new DebugPage { DataContext = DebugPageModel };
-			#else
-			DebugPage = null;
-			#endif
-
-			StatusBarModel = new StatusBarModel(db.Statistics);
-
-			AdvancedPageModel.ServerConfigurationModel.ServerStatusChanged += OnServerStatusChanged;
-			DatabaseClosed += OnDatabaseClosed;
-
-			StatusBarModel.CurrentStatus = serverManager.IsRunning ? StatusBarModel.Status.Ready : StatusBarModel.Status.Stopped;
-		}
-
-		public async Task Initialize() {
-			await TrackingPageModel.Initialize();
-			AdvancedPageModel.Initialize();
-			serverManager.Launch();
-		}
-
-		public void Dispose() {
-			ServerLauncher.ServerManagementExceptionCaught -= ServerLauncherOnServerManagementExceptionCaught;
-			ViewerPageModel.Dispose();
-			serverManager.Dispose();
-		}
-
-		private void OnServerStatusChanged(object? sender, StatusBarModel.Status e) {
-			StatusBarModel.CurrentStatus = e;
-		}
-
-		private void OnDatabaseClosed(object? sender, EventArgs e) {
-			serverManager.Stop();
-		}
-
-		private async void ServerLauncherOnServerManagementExceptionCaught(object? sender, Exception ex) {
-			Log.Error(ex);
-			await Dialog.ShowOk(window, "Internal Server Error", ex.Message);
+		remove {
+			DatabasePageModel.DatabaseClosed -= value;
 		}
 	}
+
+	private readonly Window window;
+	private readonly ServerManager serverManager;
+
+	[Obsolete("Designer")]
+	public MainContentScreenModel() : this(null!, DummyDatabaseFile.Instance) {}
+
+	public MainContentScreenModel(Window window, IDatabaseFile db) {
+		this.window = window;
+		this.serverManager = new ServerManager(db);
+
+		ServerLauncher.ServerManagementExceptionCaught += ServerLauncherOnServerManagementExceptionCaught;
+
+		DatabasePageModel = new DatabasePageModel(window, db);
+		DatabasePage = new DatabasePage { DataContext = DatabasePageModel };
+
+		TrackingPageModel = new TrackingPageModel(window);
+		TrackingPage = new TrackingPage { DataContext = TrackingPageModel };
+
+		AttachmentsPageModel = new AttachmentsPageModel(db);
+		AttachmentsPage = new AttachmentsPage { DataContext = AttachmentsPageModel };
+
+		ViewerPageModel = new ViewerPageModel(window, db);
+		ViewerPage = new ViewerPage { DataContext = ViewerPageModel };
+
+		AdvancedPageModel = new AdvancedPageModel(window, db, serverManager);
+		AdvancedPage = new AdvancedPage { DataContext = AdvancedPageModel };
+
+		#if DEBUG
+		DebugPageModel = new DebugPageModel(window, db);
+		DebugPage = new DebugPage { DataContext = DebugPageModel };
+		#else
+			DebugPage = null;
+		#endif
+
+		StatusBarModel = new StatusBarModel(db.Statistics);
+
+		AdvancedPageModel.ServerConfigurationModel.ServerStatusChanged += OnServerStatusChanged;
+		DatabaseClosed += OnDatabaseClosed;
+
+		StatusBarModel.CurrentStatus = serverManager.IsRunning ? StatusBarModel.Status.Ready : StatusBarModel.Status.Stopped;
+	}
+
+	public async Task Initialize() {
+		await TrackingPageModel.Initialize();
+		AdvancedPageModel.Initialize();
+		serverManager.Launch();
+	}
+
+	public void Dispose() {
+		ServerLauncher.ServerManagementExceptionCaught -= ServerLauncherOnServerManagementExceptionCaught;
+		AttachmentsPageModel.Dispose();
+		ViewerPageModel.Dispose();
+		serverManager.Dispose();
+	}
+
+	private void OnServerStatusChanged(object? sender, StatusBarModel.Status e) {
+		StatusBarModel.CurrentStatus = e;
+	}
+
+	private void OnDatabaseClosed(object? sender, EventArgs e) {
+		serverManager.Stop();
+	}
+
+	private async void ServerLauncherOnServerManagementExceptionCaught(object? sender, Exception ex) {
+		Log.Error(ex);
+		await Dialog.ShowOk(window, "Internal Server Error", ex.Message);
+	}
 }

app/Desktop/Main/Screens/WelcomeScreen.axaml.cs

@@ -1,16 +1,11 @@
 using System.Diagnostics.CodeAnalysis;
 using Avalonia.Controls;
-using Avalonia.Markup.Xaml;
 
-namespace DHT.Desktop.Main.Screens {
-	[SuppressMessage("ReSharper", "MemberCanBeInternal")]
-	public sealed class WelcomeScreen : UserControl {
-		public WelcomeScreen() {
-			InitializeComponent();
-		}
+namespace DHT.Desktop.Main.Screens;
 
-		private void InitializeComponent() {
-			AvaloniaXamlLoader.Load(this);
-		}
+[SuppressMessage("ReSharper", "MemberCanBeInternal")]
+public sealed partial class WelcomeScreen : UserControl {
+	public WelcomeScreen() {
+		InitializeComponent();
 	}
 }

app/Desktop/Main/Screens/WelcomeScreenModel.cs

@@ -7,67 +7,64 @@ using DHT.Desktop.Dialogs.Message;
 using DHT.Server.Database;
 using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Screens {
-	sealed class WelcomeScreenModel : BaseModel, IDisposable {
-		public string Version => Program.Version;
+namespace DHT.Desktop.Main.Screens;
 
-		public IDatabaseFile? Db { get; private set; }
-		public bool HasDatabase => Db != null;
+sealed class WelcomeScreenModel : BaseModel, IDisposable {
+	public string Version => Program.Version;
 
-		private readonly Window window;
+	public IDatabaseFile? Db { get; private set; }
+	public bool HasDatabase => Db != null;
 
-		private string? dbFilePath;
+	private readonly Window window;
 
-		[Obsolete("Designer")]
-		public WelcomeScreenModel() : this(null!) {}
+	private string? dbFilePath;
 
-		public WelcomeScreenModel(Window window) {
-			this.window = window;
-		}
+	[Obsolete("Designer")]
+	public WelcomeScreenModel() : this(null!) {}
 
-		public async void OpenOrCreateDatabase() {
-			var dialog = DatabaseGui.NewOpenOrCreateDatabaseFileDialog();
-			dialog.Directory = Path.GetDirectoryName(dbFilePath);
+	public WelcomeScreenModel(Window window) {
+		this.window = window;
+	}
 
-			string? path = await dialog.ShowAsync(window);
-			if (!string.IsNullOrWhiteSpace(path)) {
-				await OpenOrCreateDatabaseFromPath(path);
-			}
-		}
-
-		public async Task OpenOrCreateDatabaseFromPath(string path) {
-			if (Db != null) {
-				Db = null;
-			}
-
-			dbFilePath = path;
-			Db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, window, CheckCanUpgradeDatabase);
-
-			OnPropertyChanged(nameof(Db));
-			OnPropertyChanged(nameof(HasDatabase));
-		}
-
-		private async Task<bool> CheckCanUpgradeDatabase() {
-			return DialogResult.YesNo.Yes == await DatabaseGui.ShowCanUpgradeDatabaseDialog(window);
-		}
-
-		public void CloseDatabase() {
-			Dispose();
-			OnPropertyChanged(nameof(Db));
-			OnPropertyChanged(nameof(HasDatabase));
-		}
-
-		public async void ShowAboutDialog() {
-			await new AboutWindow { DataContext = new AboutWindowModel() }.ShowDialog(this.window);
-		}
-
-		public void Exit() {
-			window.Close();
-		}
-
-		public void Dispose() {
-			Db?.Dispose();
-			Db = null;
+	public async void OpenOrCreateDatabase() {
+		var path = await DatabaseGui.NewOpenOrCreateDatabaseFileDialog(window, Path.GetDirectoryName(dbFilePath));
+		if (path != null) {
+			await OpenOrCreateDatabaseFromPath(path);
 		}
 	}
+
+	public async Task OpenOrCreateDatabaseFromPath(string path) {
+		if (Db != null) {
+			Db = null;
+		}
+
+		dbFilePath = path;
+		Db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, window, CheckCanUpgradeDatabase);
+
+		OnPropertyChanged(nameof(Db));
+		OnPropertyChanged(nameof(HasDatabase));
+	}
+
+	private async Task<bool> CheckCanUpgradeDatabase() {
+		return DialogResult.YesNo.Yes == await DatabaseGui.ShowCanUpgradeDatabaseDialog(window);
+	}
+
+	public void CloseDatabase() {
+		Dispose();
+		OnPropertyChanged(nameof(Db));
+		OnPropertyChanged(nameof(HasDatabase));
+	}
+
+	public async void ShowAboutDialog() {
+		await new AboutWindow { DataContext = new AboutWindowModel() }.ShowDialog(this.window);
+	}
+
+	public void Exit() {
+		window.Close();
+	}
+
+	public void Dispose() {
+		Db?.Dispose();
+		Db = null;
+	}
 }

app/Desktop/Program.cs

@@ -3,37 +3,38 @@ using System.Reflection;
 using Avalonia;
 using DHT.Utils.Resources;
 
-namespace DHT.Desktop {
-	static class Program {
-		public static string Version { get; }
-		public static CultureInfo Culture { get; }
-		public static ResourceLoader Resources { get; }
+namespace DHT.Desktop;
 
-		static Program() {
-			var assembly = Assembly.GetExecutingAssembly();
-			
-			Version = assembly.GetName().Version?.ToString() ?? "";
-			while (Version.EndsWith(".0")) {
-				Version = Version[..^2];
-			}
+static class Program {
+	public static string Version { get; }
+	public static CultureInfo Culture { get; }
+	public static ResourceLoader Resources { get; }
 
-			Culture = CultureInfo.CurrentCulture;
-			CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
-			CultureInfo.CurrentUICulture = CultureInfo.InvariantCulture;
-			CultureInfo.DefaultThreadCurrentCulture = CultureInfo.InvariantCulture;
-			CultureInfo.DefaultThreadCurrentUICulture = CultureInfo.InvariantCulture;
-			
-			Resources = new ResourceLoader(assembly);
+	static Program() {
+		var assembly = Assembly.GetExecutingAssembly();
+
+		Version = assembly.GetName().Version?.ToString() ?? "";
+		while (Version.EndsWith(".0")) {
+			Version = Version[..^2];
 		}
 
-		public static void Main(string[] args) {
-			BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
-		}
+		Culture = CultureInfo.CurrentCulture;
+		CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
+		CultureInfo.CurrentUICulture = CultureInfo.InvariantCulture;
+		CultureInfo.DefaultThreadCurrentCulture = CultureInfo.InvariantCulture;
+		CultureInfo.DefaultThreadCurrentUICulture = CultureInfo.InvariantCulture;
 
-		private static AppBuilder BuildAvaloniaApp() {
-			return AppBuilder.Configure<App>()
-			                 .UsePlatformDetect()
-			                 .LogToTrace();
-		}
+		Resources = new ResourceLoader(assembly);
+	}
+
+	public static void Main(string[] args) {
+		BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
+	}
+
+	private static AppBuilder BuildAvaloniaApp() {
+		return AppBuilder.Configure<App>()
+		                 .UsePlatformDetect()
+		                 .WithInterFont()
+		                 .LogToTrace();
 	}
 }

app/Desktop/Server/ServerManager.cs

@@ -2,49 +2,49 @@ using System;
 using DHT.Server.Database;
 using DHT.Server.Service;
 
-namespace DHT.Desktop.Server {
-	sealed class ServerManager : IDisposable {
-		public static ushort Port { get; set; } = ServerUtils.FindAvailablePort(50000, 60000);
-		public static string Token { get; set; } = ServerUtils.GenerateRandomToken(20);
+namespace DHT.Desktop.Server;
 
-		private static ServerManager? instance;
+sealed class ServerManager : IDisposable {
+	public static ushort Port { get; set; } = ServerUtils.FindAvailablePort(50000, 60000);
+	public static string Token { get; set; } = ServerUtils.GenerateRandomToken(20);
 
-		public bool IsRunning => ServerLauncher.IsRunning;
-		
-		private readonly IDatabaseFile db;
-		
-		public ServerManager(IDatabaseFile db) {
-			if (db != DummyDatabaseFile.Instance) {
-				if (instance != null) {
-					throw new InvalidOperationException("Only one instance of ServerManager can exist at the same time!");
-				}
+	private static ServerManager? instance;
 
-				instance = this;
+	public bool IsRunning => ServerLauncher.IsRunning;
+
+	private readonly IDatabaseFile db;
+
+	public ServerManager(IDatabaseFile db) {
+		if (db != DummyDatabaseFile.Instance) {
+			if (instance != null) {
+				throw new InvalidOperationException("Only one instance of ServerManager can exist at the same time!");
 			}
 
-			this.db = db;
+			instance = this;
 		}
 
-		public void Launch() {
-			ServerLauncher.Relaunch(Port, Token, db);
-		}
+		this.db = db;
+	}
 
-		public void Relaunch(ushort port, string token) {
-			Port = port;
-			Token = token;
-			Launch();
-		}
+	public void Launch() {
+		ServerLauncher.Relaunch(Port, Token, db);
+	}
 
-		public void Stop() {
-			ServerLauncher.Stop();
-		}
+	public void Relaunch(ushort port, string token) {
+		Port = port;
+		Token = token;
+		Launch();
+	}
 
-		public void Dispose() {
-			Stop();
-			
-			if (instance == this) {
-				instance = null;
-			}
+	public void Stop() {
+		ServerLauncher.Stop();
+	}
+
+	public void Dispose() {
+		Stop();
+
+		if (instance == this) {
+			instance = null;
 		}
 	}
 }

app/Directory.build.props

@@ -0,0 +1,8 @@
+<Project>
+  
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <LangVersion>11</LangVersion>
+  </PropertyGroup>
+  
+</Project>

app/Resources/Tracker/scripts/discord.js

@@ -9,7 +9,7 @@ class DISCORD {
 	}
 	
 	static getMessageElements() {
-		return this.getMessageOuterElement().querySelectorAll("[class*='message-']");
+		return this.getMessageOuterElement().querySelectorAll("[class*='message_']");
 	}
 	
 	static hasMoreMessages() {
@@ -91,11 +91,13 @@ class DISCORD {
 	static getMessageElementProps(ele) {
 		const props = DOM.getReactProps(ele);
 		
-		if (props.children && props.children.length >= 4) {
-			const childProps = props.children[3].props;
-			
-			if ("message" in childProps && "channel" in childProps) {
-				return childProps;
+		if (props.children && props.children.length) {
+			for (let i = 3; i < props.children.length; i++) {
+				const childProps = props.children[i].props;
+				
+				if (childProps && "message" in childProps && "channel" in childProps) {
+					return childProps;
+				}
 			}
 		}
 		
@@ -110,16 +112,20 @@ class DISCORD {
 			const messages = [];
 			
 			for (const ele of this.getMessageElements()) {
-				const props = this.getMessageElementProps(ele);
-				
-				if (props != null) {
-					messages.push(props.message);
+				try {
+					const props = this.getMessageElementProps(ele);
+					
+					if (props != null) {
+						messages.push(props.message);
+					}
+				} catch (e) {
+					console.error("[DHT] Error extracing message data, skipping it.", e, ele, DOM.tryGetReactProps(ele));
 				}
 			}
 			
 			return messages;
 		} catch (e) {
-			console.error(e);
+			console.error("[DHT] Error retrieving messages.", e);
 			return [];
 		}
 	}
@@ -162,7 +168,7 @@ class DISCORD {
 			if (dms) {
 				let name;
 				
-				for (const ele of dms.querySelectorAll("[class*='channel-'] [class*='selected-'] [class^='name-'] *, [class*='channel-'][class*='selected-'] [class^='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) {
@@ -191,9 +197,22 @@ class DISCORD {
 				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": obj.guild_id,
-					"name": document.querySelector("nav header h1[class*='name-']").innerText,
+					"id": guild.id,
+					"name": guild.name,
 					"type": "SERVER"
 				};
 				
@@ -232,10 +251,10 @@ class DISCORD {
 		
 		if (dms) {
 			const currentChannel = DOM.queryReactClass("selected", dms);
-			const currentChannelContainer = currentChannel && currentChannel.closest("[class*='channel-']");
+			const currentChannelContainer = currentChannel && currentChannel.closest("[class*='channel_']");
 			const nextChannel = currentChannelContainer && currentChannelContainer.nextElementSibling;
 			
-			if (!nextChannel || !nextChannel.getAttribute("class").includes("channel-")) {
+			if (!nextChannel || !nextChannel.getAttribute("class").includes("channel_")) {
 				return false;
 			}
 			
@@ -262,7 +281,7 @@ class DISCORD {
 			let nextChannel = null;
 			
 			for (let index = 0; index < allTextChannels.length - 1; index++) {
-				if (allTextChannels[index].className.includes("selected-")) {
+				if (allTextChannels[index].className.includes("selected_")) {
 					nextChannel = allTextChannels[index + 1];
 					break;
 				}

app/Resources/Tracker/scripts/dom.js

@@ -11,7 +11,7 @@ class DOM {
 	 * Returns the first child element containing the specified obfuscated class. Parent defaults to the entire document.
 	 */
 	static queryReactClass(cls, parent) {
-		return (parent || document).querySelector(`[class*="${cls}-"]`);
+		return (parent || document).querySelector(`[class*="${cls}_"]`);
 	}
 	
 	/**
@@ -71,4 +71,15 @@ class DOM {
 		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/state.js

@@ -251,6 +251,11 @@ const STATE = (function() {
 							mapped.type = attachment.content_type;
 						}
 						
+						if (attachment.width && attachment.height) {
+							mapped.width = attachment.width;
+							mapped.height = attachment.height;
+						}
+						
 						return mapped;
 					});
 				}

app/Resources/Tracker/styles/controller.css

@@ -1,5 +1,5 @@
-#app-mount div[class*="app-"] {
-  margin-bottom: 48px !important;
+#app-mount {
+  height: calc(100% - 48px) !important;
 }
 
 #dht-ctrl {

app/Resources/Viewer/scripts/discord.js

@@ -1,7 +1,7 @@
 const DISCORD = (function() {
 	const regex = {
 		formatBold: /\*\*([\s\S]+?)\*\*(?!\*)/g,
-		formatItalic: /(.)?\*([\s\S]+?)\*(?!\*)/g,
+		formatItalic: /(.)?([_*])([\s\S]+?)\2(?!\2)/g,
 		formatUnderline: /__([\s\S]+?)__(?!_)/g,
 		formatStrike: /~~([\s\S]+?)~~(?!~)/g,
 		formatCodeInline: /(`+)\s*([\s\S]*?[^`])\s*\1(?!`)/g,
@@ -9,7 +9,7 @@ const DISCORD = (function() {
 		formatUrl: /(\b(?:https?|ftp|file):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/ig,
 		formatUrlNoEmbed: /<(\b(?:https?|ftp|file):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])>/ig,
 		specialEscapedBacktick: /\\`/g,
-		specialEscapedSingle: /\\([*\\])/g,
+		specialEscapedSingle: /\\([*_\\])/g,
 		specialEscapedDouble: /\\__|_\\_|\\_\\_|\\~~|~\\~|\\~\\~/g,
 		specialUnescaped: /([*_~\\])/g,
 		mentionRole: /&lt;@&(\d+?)&gt;/g,
@@ -26,6 +26,7 @@ const DISCORD = (function() {
 	let templateUserAvatar;
 	let templateAttachmentDownload;
 	let templateEmbedImage;
+	let templateEmbedImageWithSize;
 	let templateEmbedRich;
 	let templateEmbedRichNoDescription;
 	let templateEmbedUrl;
@@ -46,8 +47,8 @@ const DISCORD = (function() {
 				.replace(regex.specialEscapedSingle, escapeHtmlMatch)
 				.replace(regex.specialEscapedDouble, full => full.replace(/\\/g, "").replace(/(.)/g, escapeHtmlMatch))
 				.replace(regex.formatBold, "<b>$1</b>")
-				.replace(regex.formatItalic, (full, pre, match) => pre === "\\" ? full : (pre || "") + "<i>" + match + "</i>")
 				.replace(regex.formatUnderline, "<u>$1</u>")
+				.replace(regex.formatItalic, (full, pre, char, match) => pre === "\\" ? full : (pre || "") + "<i>" + match + "</i>")
 				.replace(regex.formatStrike, "<s>$1</s>");
 		}
 		
@@ -64,6 +65,25 @@ const DISCORD = (function() {
 		return "<p>" + processed + "</p>";
 	};
 	
+	const getImageEmbed = function(url, image) {
+		if (!SETTINGS.enableImagePreviews) {
+			return "";
+		}
+		
+		if (image.width && image.height) {
+			return templateEmbedImageWithSize.apply({ url, src: image.url, width: image.width, height: image.height });
+		}
+		else {
+			return templateEmbedImage.apply({ url, src: image.url });
+		}
+	};
+	
+	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 {
 		setup() {
 			templateChannelServer = new TEMPLATE([
@@ -109,12 +129,17 @@ const DISCORD = (function() {
 			
 			// noinspection HtmlUnknownTarget
 			templateAttachmentDownload = new TEMPLATE([
-				"<a href='{url}' class='embed download'>Download {filename}</a>"
+				"<a href='{url}' class='embed download'>Download {name}</a>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
 			templateEmbedImage = new TEMPLATE([
-				"<a href='{url}' class='embed thumbnail'><img src='{src}' alt='(image attachment not found)'></a><br>"
+				"<a href='{url}' class='embed thumbnail loading'><img src='{src}' alt='' onload='DISCORD.handleImageLoad(this)' onerror='DISCORD.handleImageLoadError(this)'></a><br>"
+			].join(""));
+			
+			// noinspection HtmlUnknownTarget
+			templateEmbedImageWithSize = new TEMPLATE([
+				"<a href='{url}' class='embed thumbnail loading'><img src='{src}' width='{width}' height='{height}' alt='' onload='DISCORD.handleImageLoad(this)' onerror='DISCORD.handleImageLoadError(this)'></a><br>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
@@ -145,10 +170,20 @@ const DISCORD = (function() {
 			].join(""));
 		},
 		
+		handleImageLoad(ele) {
+			ele.parentElement.classList.remove("loading");
+		},
+		
+		handleImageLoadError(ele) {
+			// noinspection JSUnusedGlobalSymbols
+			ele.onerror = null;
+			ele.parentElement.classList.remove("loading");
+			ele.setAttribute("alt", "(image attachment not found)");
+		},
+		
 		isImageAttachment(attachment) {
-			const dot = attachment.url.lastIndexOf(".");
-			const ext = dot === -1 ? "" : attachment.url.substring(dot).toLowerCase();
-			return ext === ".png" || ext === ".gif" || ext === ".jpg" || ext === ".jpeg";
+			const url = DOM.tryParseUrl(attachment.url);
+			return url != null && isImageUrl(url);
 		},
 		
 		getChannelHTML(channel) { // noinspection FunctionWithInconsistentReturnsJS
@@ -183,10 +218,10 @@ const DISCORD = (function() {
 							return templateEmbedUnsupported.apply(embed);
 						}
 						else if ("image" in embed && embed.image.url) {
-							return SETTINGS.enableImagePreviews ? templateEmbedImage.apply({ url: embed.url, src: embed.image.url }) : "";
+							return getImageEmbed(embed.url, embed.image);
 						}
 						else if ("thumbnail" in embed && embed.thumbnail.url) {
-							return SETTINGS.enableImagePreviews ? templateEmbedImage.apply({ url: embed.url, src: embed.thumbnail.url }) : "";
+							return getImageEmbed(embed.url, embed.thumbnail);
 						}
 						else if ("title" in embed && "description" in embed) {
 							return templateEmbedRich.apply(embed);
@@ -205,16 +240,14 @@ const DISCORD = (function() {
 					}
 					
 					return value.map(attachment => {
-						if (this.isImageAttachment(attachment) && SETTINGS.enableImagePreviews) {
-							return templateEmbedImage.apply({ url: attachment.url, src: attachment.url });
+						if (!DISCORD.isImageAttachment(attachment) || !SETTINGS.enableImagePreviews) {
+							return templateAttachmentDownload.apply(attachment);
+						}
+						else if ("width" in attachment && "height" in attachment) {
+							return templateEmbedImageWithSize.apply({ url: attachment.url, src: attachment.url, width: attachment.width, height: attachment.height });
 						}
 						else {
-							const sliced = attachment.url.split("/");
-							
-							return templateAttachmentDownload.apply({
-								"url": attachment.url,
-								"filename": sliced[sliced.length - 1]
-							});
+							return templateEmbedImage.apply({ url: attachment.url, src: attachment.url });
 						}
 					}).join("");
 				}

app/Resources/Viewer/scripts/dom.js

@@ -51,4 +51,15 @@ class DOM {
 		const date = new Date(timestamp);
 		return date.toLocaleDateString() + ", " + date.toLocaleTimeString();
 	};
+	
+	/**
+	 * Parses a url string into a URL object and returns it. If the parsing fails, returns null.
+	 */
+	static tryParseUrl(url) {
+		try {
+			return new URL(url);
+		} catch (ignore) {
+			return null;
+		}
+	}
 }

app/Resources/Viewer/styles/messages.css

@@ -107,11 +107,25 @@
 }
 
 .message .thumbnail {
+  position: relative;
   max-width: calc(100% - 20px);
   max-height: 320px;
 }
 
+.message .thumbnail.loading::after {
+  content: "";
+  background: rgba(0, 0, 0, 0.75)
+              url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 300 300' preserveAspectRatio='xMidYMid'%3E %3Ccircle cx='150' cy='150' fill='none' stroke='%237983f5' stroke-width='8' r='42' stroke-dasharray='198 68'%3E %3CanimateTransform attributeName='transform' type='rotate' repeatCount='indefinite' dur='1.25s' values='0 150 150;360 150 150' keyTimes='0;1' /%3E %3C/circle%3E %3C/svg%3E")
+              no-repeat center center;
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+}
+
 .message .thumbnail img {
+  width: auto;
   max-width: 100%;
   max-height: 320px;
   border-radius: 3px;

app/Server/Data/Aggregations/DownloadStatusStatistics.cs

@@ -0,0 +1,15 @@
+namespace DHT.Server.Data.Aggregations;
+
+public sealed class DownloadStatusStatistics {
+	public int EnqueuedCount { get; internal set; }
+	public ulong EnqueuedSize { get; internal set; }
+
+	public int SuccessfulCount { get; internal set; }
+	public ulong SuccessfulSize { get; internal set; }
+
+	public int FailedCount { get; internal set; }
+	public ulong FailedSize { get; internal set; }
+
+	public int SkippedCount { get; internal set; }
+	public ulong SkippedSize { get; internal set; }
+}

app/Server/Data/Attachment.cs

@@ -1,9 +1,11 @@
-namespace DHT.Server.Data {
-	public readonly struct Attachment {
-		public ulong Id { get; internal init; }
-		public string Name { get; internal init; }
-		public string? Type { get; internal init; }
-		public string Url { get; internal init; }
-		public ulong Size { get; internal init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct Attachment {
+	public ulong Id { get; internal init; }
+	public string Name { get; internal init; }
+	public string? Type { get; internal init; }
+	public string Url { get; internal init; }
+	public ulong Size { get; internal init; }
+	public int? Width { get; internal init; }
+	public int? Height { get; internal init; }
 }

app/Server/Data/Channel.cs

@@ -1,11 +1,11 @@
-namespace DHT.Server.Data {
-	public readonly struct Channel {
-		public ulong Id { get; init; }
-		public ulong Server { get; init; }
-		public string Name { get; init; }
-		public ulong? ParentId { get; init; }
-		public int? Position { get; init; }
-		public string? Topic { get; init; }
-		public bool? Nsfw { get; init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct Channel {
+	public ulong Id { get; init; }
+	public ulong Server { get; init; }
+	public string Name { get; init; }
+	public ulong? ParentId { get; init; }
+	public int? Position { get; init; }
+	public string? Topic { get; init; }
+	public bool? Nsfw { get; init; }
 }

app/Server/Data/Download.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Net;
+
+namespace DHT.Server.Data;
+
+public readonly struct Download {
+	internal static Download NewSuccess(string url, byte[] data) {
+		return new Download(url, DownloadStatus.Success, (ulong) Math.Max(data.LongLength, 0), data);
+	}
+
+	internal static Download NewFailure(string url, HttpStatusCode? statusCode, ulong size) {
+		return new Download(url, statusCode.HasValue ? (DownloadStatus) (int) statusCode : DownloadStatus.GenericError, size);
+	}
+
+	public string Url { get; }
+	public DownloadStatus Status { get; }
+	public ulong Size { get; }
+	public byte[]? Data { get; }
+
+	internal Download(string url, DownloadStatus status, ulong size, byte[]? data = null) {
+		Url = url;
+		Status = status;
+		Size = size;
+		Data = data;
+	}
+
+	internal Download WithData(byte[] data) {
+		return new Download(Url, Status, Size, data);
+	}
+}

app/Server/Data/DownloadStatus.cs

@@ -0,0 +1,12 @@
+using System.Net;
+
+namespace DHT.Server.Data;
+
+/// <summary>
+/// Extends <see cref="HttpStatusCode"/> with custom status codes in the range 0-99.
+/// </summary>
+public enum DownloadStatus {
+	Enqueued = 0,
+	GenericError = 1,
+	Success = HttpStatusCode.OK
+}

app/Server/Data/DownloadedAttachment.cs

@@ -0,0 +1,6 @@
+namespace DHT.Server.Data;
+
+public readonly struct DownloadedAttachment {
+	public string? Type { get; internal init; }
+	public byte[] Data { get; internal init; }
+}

app/Server/Data/Embed.cs

@@ -1,5 +1,5 @@
-namespace DHT.Server.Data {
-	public readonly struct Embed {
-		public string Json { get; internal init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct Embed {
+	public string Json { get; internal init; }
 }

app/Server/Data/EmojiFlags.cs

@@ -1,9 +1,9 @@
 using System;
 
-namespace DHT.Server.Data {
-	[Flags]
-	public enum EmojiFlags : ushort {
-		None = 0,
-		Animated = 0b1
-	}
+namespace DHT.Server.Data;
+
+[Flags]
+public enum EmojiFlags : ushort {
+	None = 0,
+	Animated = 0b1
 }

app/Server/Data/Filters/AttachmentFilter.cs

@@ -0,0 +1,15 @@
+namespace DHT.Server.Data.Filters;
+
+public sealed class AttachmentFilter {
+	public ulong? MaxBytes { get; set; } = null;
+
+	public DownloadItemRules? DownloadItemRule { get; set; } = null;
+
+	public bool IsEmpty => MaxBytes == null &&
+	                       DownloadItemRule == null;
+
+	public enum DownloadItemRules {
+		OnlyNotPresent,
+		OnlyPresent
+	}
+}

app/Server/Data/Filters/DownloadItemFilter.cs

@@ -0,0 +1,10 @@
+using System.Collections.Generic;
+
+namespace DHT.Server.Data.Filters;
+
+public sealed class DownloadItemFilter {
+	public HashSet<DownloadStatus>? IncludeStatuses { get; init; } = null;
+	public HashSet<DownloadStatus>? ExcludeStatuses { get; init; } = null;
+
+	public bool IsEmpty => IncludeStatuses == null && ExcludeStatuses == null;
+}

app/Server/Data/Filters/FilterRemovalMode.cs

@@ -0,0 +1,6 @@
+namespace DHT.Server.Data.Filters;
+
+public enum FilterRemovalMode {
+	KeepMatching,
+	RemoveMatching
+}

app/Server/Data/Filters/MessageFilter.cs

@@ -1,19 +1,19 @@
 using System;
 using System.Collections.Generic;
 
-namespace DHT.Server.Data.Filters {
-	public sealed class MessageFilter {
-		public DateTime? StartDate { get; set; } = null;
-		public DateTime? EndDate { get; set; } = null;
+namespace DHT.Server.Data.Filters;
 
-		public HashSet<ulong>? ChannelIds { get; set; } = null;
-		public HashSet<ulong>? UserIds { get; set; } = null;
-		public HashSet<ulong>? MessageIds { get; set; } = null;
+public sealed class MessageFilter {
+	public DateTime? StartDate { get; set; } = null;
+	public DateTime? EndDate { get; set; } = null;
 
-		public bool IsEmpty => StartDate == null &&
-		                       EndDate == null &&
-		                       ChannelIds == null &&
-		                       UserIds == null &&
-		                       MessageIds == null;
-	}
+	public HashSet<ulong>? ChannelIds { get; set; } = null;
+	public HashSet<ulong>? UserIds { get; set; } = null;
+	public HashSet<ulong>? MessageIds { get; set; } = null;
+
+	public bool IsEmpty => StartDate == null &&
+	                       EndDate == null &&
+	                       ChannelIds == null &&
+	                       UserIds == null &&
+	                       MessageIds == null;
 }

app/Server/Data/Filters/MessageFilterRemovalMode.cs

@@ -1,6 +0,0 @@
-namespace DHT.Server.Data.Filters {
-	public enum MessageFilterRemovalMode {
-		KeepMatching,
-		RemoveMatching
-	}
-}

app/Server/Data/Message.cs

@@ -1,16 +1,16 @@
 using System.Collections.Immutable;
 
-namespace DHT.Server.Data {
-	public readonly struct Message {
-		public ulong Id { get; init; }
-		public ulong Sender { get; init; }
-		public ulong Channel { get; init; }
-		public string Text { get; init; }
-		public long Timestamp { get; init; }
-		public long? EditTimestamp { get; init; }
-		public ulong? RepliedToId { get; init; }
-		public ImmutableArray<Attachment> Attachments { get; init; }
-		public ImmutableArray<Embed> Embeds { get; init; }
-		public ImmutableArray<Reaction> Reactions { get; init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct Message {
+	public ulong Id { get; init; }
+	public ulong Sender { get; init; }
+	public ulong Channel { get; init; }
+	public string Text { get; init; }
+	public long Timestamp { get; init; }
+	public long? EditTimestamp { get; init; }
+	public ulong? RepliedToId { get; init; }
+	public ImmutableArray<Attachment> Attachments { get; init; }
+	public ImmutableArray<Embed> Embeds { get; init; }
+	public ImmutableArray<Reaction> Reactions { get; init; }
 }

app/Server/Data/Reaction.cs

@@ -1,8 +1,8 @@
-namespace DHT.Server.Data {
-	public readonly struct Reaction {
-		public ulong? EmojiId { get; internal init; }
-		public string? EmojiName { get; internal init; }
-		public EmojiFlags EmojiFlags { get; internal init; }
-		public int Count { get; internal init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct Reaction {
+	public ulong? EmojiId { get; internal init; }
+	public string? EmojiName { get; internal init; }
+	public EmojiFlags EmojiFlags { get; internal init; }
+	public int Count { get; internal init; }
 }

app/Server/Data/Server.cs

@@ -1,7 +1,7 @@
-namespace DHT.Server.Data {
-	public readonly struct Server {
-		public ulong Id { get; init; }
-		public string Name { get; init; }
-		public ServerType? Type { get; init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct Server {
+	public ulong Id { get; init; }
+	public string Name { get; init; }
+	public ServerType? Type { get; init; }
 }

app/Server/Data/ServerType.cs

@@ -1,36 +1,45 @@
-namespace DHT.Server.Data {
-	public enum ServerType {
-		Server,
-		Group,
-		DirectMessage
+namespace DHT.Server.Data;
+
+public enum ServerType {
+	Server,
+	Group,
+	DirectMessage
+}
+
+public static class ServerTypes {
+	public static ServerType? FromString(string? str) {
+		return str switch {
+			"SERVER" => ServerType.Server,
+			"GROUP"  => ServerType.Group,
+			"DM"     => ServerType.DirectMessage,
+			_        => null
+		};
 	}
 
-	public static class ServerTypes {
-		public static ServerType? FromString(string? str) {
-			return str switch {
-				"SERVER" => ServerType.Server,
-				"GROUP"  => ServerType.Group,
-				"DM"     => ServerType.DirectMessage,
-				_        => null
-			};
-		}
+	public static string ToString(ServerType? type) {
+		return type switch {
+			ServerType.Server        => "SERVER",
+			ServerType.Group         => "GROUP",
+			ServerType.DirectMessage => "DM",
+			_                        => "UNKNOWN"
+		};
+	}
 
-		public static string ToString(ServerType? type) {
-			return type switch {
-				ServerType.Server        => "SERVER",
-				ServerType.Group         => "GROUP",
-				ServerType.DirectMessage => "DM",
-				_                        => "UNKNOWN"
-			};
-		}
+	public static string ToNiceString(ServerType? type) {
+		return type switch {
+			ServerType.Server        => "Server",
+			ServerType.Group         => "Group",
+			ServerType.DirectMessage => "DM",
+			_                        => "Unknown"
+		};
+	}
 
-		internal static string ToJsonViewerString(ServerType? type) {
-			return type switch {
-				ServerType.Server        => "server",
-				ServerType.Group         => "group",
-				ServerType.DirectMessage => "user",
-				_                        => "unknown"
-			};
-		}
+	internal static string ToJsonViewerString(ServerType? type) {
+		return type switch {
+			ServerType.Server        => "server",
+			ServerType.Group         => "group",
+			ServerType.DirectMessage => "user",
+			_                        => "unknown"
+		};
 	}
 }

app/Server/Data/User.cs

@@ -1,8 +1,8 @@
-namespace DHT.Server.Data {
-	public readonly struct User {
-		public ulong Id { get; init; }
-		public string Name { get; init; }
-		public string? AvatarUrl { get; init; }
-		public string? Discriminator { get; init; }
-	}
+namespace DHT.Server.Data;
+
+public readonly struct User {
+	public ulong Id { get; init; }
+	public string Name { get; init; }
+	public string? AvatarUrl { get; init; }
+	public string? Discriminator { get; init; }
 }

app/Server/Database/DatabaseExtensions.cs

@@ -1,16 +1,29 @@
-namespace DHT.Server.Database {
-	public static class DatabaseExtensions {
-		public static void AddFrom(this IDatabaseFile target, IDatabaseFile source) {
-			foreach (var server in source.GetAllServers()) {
-				target.AddServer(server);
-			}
+using System.Collections.Generic;
+using DHT.Server.Data;
 
-			foreach (var channel in source.GetAllChannels()) {
-				target.AddChannel(channel);
-			}
+namespace DHT.Server.Database;
 
-			target.AddUsers(source.GetAllUsers().ToArray());
-			target.AddMessages(source.GetMessages().ToArray());
+public static class DatabaseExtensions {
+	public static void AddFrom(this IDatabaseFile target, IDatabaseFile source) {
+		target.AddServers(source.GetAllServers());
+		target.AddChannels(source.GetAllChannels());
+		target.AddUsers(source.GetAllUsers().ToArray());
+		target.AddMessages(source.GetMessages().ToArray());
+
+		foreach (var download in source.GetDownloadsWithoutData()) {
+			target.AddDownload(download.Status == DownloadStatus.Success ? source.GetDownloadWithData(download) : download);
+		}
+	}
+
+	internal static void AddServers(this IDatabaseFile target, IEnumerable<Data.Server> servers) {
+		foreach (var server in servers) {
+			target.AddServer(server);
+		}
+	}
+
+	internal static void AddChannels(this IDatabaseFile target, IEnumerable<Channel> channels) {
+		foreach (var channel in channels) {
+			target.AddChannel(channel);
 		}
 	}
 }

app/Server/Database/DatabaseStatistics.cs

@@ -1,39 +1,46 @@
 using DHT.Utils.Models;
 
-namespace DHT.Server.Database {
-	public sealed class DatabaseStatistics : BaseModel {
-		private long totalServers;
-		private long totalChannels;
-		private long totalUsers;
-		private long? totalMessages;
+namespace DHT.Server.Database;
 
-		public long TotalServers {
-			get => totalServers;
-			internal set => Change(ref totalServers, value);
-		}
+/// <summary>
+/// A live view of database statistics.
+/// Some of the totals are computed asynchronously and may not reflect the most recent version of the database, or may not be available at all until computed for the first time.
+/// </summary>
+public sealed class DatabaseStatistics : BaseModel {
+	private long totalServers;
+	private long totalChannels;
+	private long totalUsers;
+	private long? totalMessages;
+	private long? totalAttachments;
+	private long? totalDownloads;
 
-		public long TotalChannels {
-			get => totalChannels;
-			internal set => Change(ref totalChannels, value);
-		}
+	public long TotalServers {
+		get => totalServers;
+		internal set => Change(ref totalServers, value);
+	}
 
-		public long TotalUsers {
-			get => totalUsers;
-			internal set => Change(ref totalUsers, value);
-		}
+	public long TotalChannels {
+		get => totalChannels;
+		internal set => Change(ref totalChannels, value);
+	}
 
-		public long? TotalMessages {
-			get => totalMessages;
-			internal set => Change(ref totalMessages, value);
-		}
+	public long TotalUsers {
+		get => totalUsers;
+		internal set => Change(ref totalUsers, value);
+	}
 
-		public DatabaseStatistics Clone() {
-			return new DatabaseStatistics {
-				totalServers = totalServers,
-				totalChannels = totalChannels,
-				totalUsers = TotalUsers,
-				totalMessages = totalMessages
-			};
-		}
+	public long? TotalMessages {
+		get => totalMessages;
+		internal set => Change(ref totalMessages, value);
+	}
+
+	public long? TotalAttachments {
+		get => totalAttachments;
+		internal set => Change(ref totalAttachments, value);
+	}
+
+	public long? TotalDownloads {
+		get => totalDownloads;
+		internal set => Change(ref totalDownloads, value);
 	}
 }

app/Server/Database/DatabaseStatisticsSnapshot.cs

@@ -0,0 +1,11 @@
+namespace DHT.Server.Database;
+
+/// <summary>
+/// A complete snapshot of database statistics at a particular point in time.
+/// </summary>
+public readonly struct DatabaseStatisticsSnapshot {
+	public long TotalServers { get; internal init; }
+	public long TotalChannels { get; internal init; }
+	public long TotalUsers { get; internal init; }
+	public long TotalMessages { get; internal init; }
+}