Release v42.0

Closes #256

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

@@ -9,15 +9,15 @@
         <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/AttachmentFilterPanel.axaml" value="Desktop/Desktop.csproj" />
+        <entry key="Desktop/Main/Controls/DownloadItemFilterPanel.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/DownloadsPage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/TrackingPage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Pages/ViewerPage.axaml" value="Desktop/Desktop.csproj" />
         <entry key="Desktop/Main/Screens/MainContentScreen.axaml" value="Desktop/Desktop.csproj" />
@@ -25,4 +25,4 @@
       </map>
     </option>
   </component>
-</project>
+</project>

app/.idea/.idea.DiscordHistoryTracker/.idea/codeStyles/Project.xml

@@ -13,10 +13,10 @@
     <CssCodeStyleSettings>
       <option name="HEX_COLOR_LOWER_CASE" value="true" />
     </CssCodeStyleSettings>
-    <DB2CodeStyleSettings version="6">
+    <DB2CodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </DB2CodeStyleSettings>
-    <DerbyCodeStyleSettings version="6">
+    <DerbyCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </DerbyCodeStyleSettings>
     <GoCodeStyleSettings>
@@ -26,10 +26,10 @@
       <option name="WRAP_FUNC_PARAMS" value="5" />
       <option name="WRAP_FUNC_RESULT" value="5" />
     </GoCodeStyleSettings>
-    <H2CodeStyleSettings version="6">
+    <H2CodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </H2CodeStyleSettings>
-    <HSQLCodeStyleSettings version="6">
+    <HSQLCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </HSQLCodeStyleSettings>
     <HTMLCodeStyleSettings>
@@ -85,10 +85,10 @@
     <LessCodeStyleSettings>
       <option name="HEX_COLOR_LOWER_CASE" value="true" />
     </LessCodeStyleSettings>
-    <MSSQLCodeStyleSettings version="6">
+    <MSSQLCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </MSSQLCodeStyleSettings>
-    <MySQLCodeStyleSettings version="6">
+    <MySQLCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </MySQLCodeStyleSettings>
     <Objective-C>
@@ -98,7 +98,7 @@
       <option name="SPACE_BEFORE_INIT_LIST" value="true" />
       <option name="SPACE_AFTER_DICTIONARY_LITERAL_COLON" value="false" />
     </Objective-C>
-    <OracleCodeStyleSettings version="6">
+    <OracleCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </OracleCodeStyleSettings>
     <PHPCodeStyleSettings>
@@ -116,7 +116,7 @@
       <option name="NEW_LINE_AFTER_PHP_OPENING_TAG" value="true" />
       <option name="SPACE_AROUND_ASSIGNMENT_IN_DECLARE" value="true" />
     </PHPCodeStyleSettings>
-    <PostgresCodeStyleSettings version="6">
+    <PostgresCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </PostgresCodeStyleSettings>
     <Properties>
@@ -143,13 +143,16 @@
       <option name="INDENT_WHEN_CASES" value="true" />
       <option name="CHAIN_CALLS_ALIGNMENT" value="2" />
     </Ruby>
-    <SQLiteCodeStyleSettings version="6">
+    <SQLiteCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </SQLiteCodeStyleSettings>
     <ScssCodeStyleSettings>
       <option name="HEX_COLOR_LOWER_CASE" value="true" />
     </ScssCodeStyleSettings>
-    <SqlCodeStyleSettings version="6">
+    <Shell_Script>
+      <option name="KEEP_COLUMN_ALIGNMENT_PADDING" value="true" />
+    </Shell_Script>
+    <SqlCodeStyleSettings version="7">
       <option name="KEYWORD_CASE" value="2" />
       <option name="TYPE_CASE" value="2" />
       <option name="CUSTOM_TYPE_CASE" value="2" />
@@ -173,9 +176,10 @@
       <option name="CONSTRAINT_WRAP_3" value="true" />
       <option name="CONSTRAINT_WRAP_4" value="true" />
       <option name="VIEW_INDENT_QUERY" value="true" />
+      <option name="IMP_LOOP_LOOP_INDENT" value="false" />
       <option name="EXPR_CASE_WHEN_WRAP" value="false" />
     </SqlCodeStyleSettings>
-    <SybaseCodeStyleSettings version="6">
+    <SybaseCodeStyleSettings version="7">
       <option name="USE_GENERIC_STYLE" value="true" />
     </SybaseCodeStyleSettings>
     <TypeScriptCodeStyleSettings version="0">
@@ -203,6 +207,11 @@
         <option name="KEEP_INDENTS_ON_EMPTY_LINES" value="true" />
       </indentOptions>
     </codeStyleSettings>
+    <codeStyleSettings language="Gherkin">
+      <indentOptions>
+        <option name="KEEP_INDENTS_ON_EMPTY_LINES" value="true" />
+      </indentOptions>
+    </codeStyleSettings>
     <codeStyleSettings language="Groovy">
       <option name="ELSE_ON_NEW_LINE" value="true" />
       <option name="SPACE_WITHIN_ARRAY_INITIALIZER_BRACES" value="true" />
@@ -282,6 +291,13 @@
         <option name="KEEP_INDENTS_ON_EMPTY_LINES" value="true" />
       </indentOptions>
     </codeStyleSettings>
+    <codeStyleSettings language="Markdown">
+      <indentOptions>
+        <option name="INDENT_SIZE" value="2" />
+        <option name="CONTINUATION_INDENT_SIZE" value="2" />
+        <option name="TAB_SIZE" value="2" />
+      </indentOptions>
+    </codeStyleSettings>
     <codeStyleSettings language="ObjectiveC">
       <option name="LINE_COMMENT_AT_FIRST_COLUMN" value="false" />
       <option name="BLOCK_COMMENT_AT_FIRST_COLUMN" value="false" />
@@ -342,7 +358,6 @@
       </indentOptions>
     </codeStyleSettings>
     <codeStyleSettings language="Rust">
-      <option name="RIGHT_MARGIN" value="140" />
       <option name="ALIGN_MULTILINE_CHAINED_METHODS" value="true" />
       <indentOptions>
         <option name="USE_TAB_CHARACTER" value="true" />
@@ -357,6 +372,7 @@
     </codeStyleSettings>
     <codeStyleSettings language="SCSS">
       <indentOptions>
+        <option name="CONTINUATION_INDENT_SIZE" value="2" />
         <option name="KEEP_INDENTS_ON_EMPTY_LINES" value="true" />
       </indentOptions>
     </codeStyleSettings>
@@ -367,13 +383,6 @@
         <option name="KEEP_INDENTS_ON_EMPTY_LINES" value="true" />
       </indentOptions>
     </codeStyleSettings>
-    <codeStyleSettings language="Shell Script">
-      <indentOptions>
-        <option name="INDENT_SIZE" value="4" />
-        <option name="TAB_SIZE" value="4" />
-        <option name="USE_TAB_CHARACTER" value="true" />
-      </indentOptions>
-    </codeStyleSettings>
     <codeStyleSettings language="TOML">
       <indentOptions>
         <option name="CONTINUATION_INDENT_SIZE" value="4" />
@@ -427,6 +436,9 @@
     </codeStyleSettings>
     <codeStyleSettings language="liquid">
       <indentOptions>
+        <option name="INDENT_SIZE" value="2" />
+        <option name="CONTINUATION_INDENT_SIZE" value="2" />
+        <option name="TAB_SIZE" value="2" />
         <option name="KEEP_INDENTS_ON_EMPTY_LINES" value="true" />
       </indentOptions>
     </codeStyleSettings>
@@ -442,4 +454,4 @@
       </indentOptions>
     </codeStyleSettings>
   </code_scheme>
-</component>
+</component>

app/.idea/.idea.DiscordHistoryTracker/.idea/inspectionProfiles/Project.xml

@@ -91,7 +91,6 @@
     <inspection_tool class="ComparatorNotSerializable" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="CompareToUsesNonFinalVariable" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="ComparisonOfShortAndChar" enabled="true" level="WARNING" enabled_by_default="true" />
-    <inspection_tool class="ComposeMissingKeys" enabled="true" level="ERROR" enabled_by_default="true" />
     <inspection_tool class="ConditionSignal" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="ConditionalExpression" enabled="true" level="INFORMATION" enabled_by_default="true">
       <option name="ignoreSimpleAssignmentsAndReturns" value="true" />
@@ -362,7 +361,7 @@
     </inspection_tool>
     <inspection_tool class="LocalVariableDeclarationSideOnly" enabled="true" level="ERROR" enabled_by_default="true" />
     <inspection_tool class="LocalVariableNamingConventionJS" enabled="true" level="WARNING" enabled_by_default="true">
-      <option name="m_regex" value="[a-z][A-Za-z]*" />
+      <option name="m_regex" value="[a-z][A-Za-z0-9]*" />
       <option name="m_minLength" value="0" />
       <option name="m_maxLength" value="99" />
     </inspection_tool>

app/.idea/.idea.DiscordHistoryTracker/.idea/libraries/Generated_files.xml

@@ -1,22 +0,0 @@
-<component name="libraryTable">
-  <library name="Generated files" type="javaScript">
-    <properties>
-      <sourceFilesUrls>
-        <item url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/discord.js" />
-        <item url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/dom.js" />
-        <item url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/gui.js" />
-        <item url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/settings.js" />
-        <item url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/state.js" />
-      </sourceFilesUrls>
-    </properties>
-    <CLASSES>
-      <root url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/discord.js" />
-      <root url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/dom.js" />
-      <root url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/gui.js" />
-      <root url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/settings.js" />
-      <root url="file://$PROJECT_DIR$/Resources/Tracker/scripts.min/state.js" />
-    </CLASSES>
-    <JAVADOC />
-    <SOURCES />
-  </library>
-</component>

app/Desktop/App.axaml.cs

@@ -1,4 +1,3 @@
-using System;
 using Avalonia;
 using Avalonia.Controls.ApplicationLifetimes;
 using Avalonia.Markup.Xaml;
@@ -13,7 +12,7 @@ sealed class App : Application {
 
 	public override void OnFrameworkInitializationCompleted() {
 		if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop) {
-			desktop.MainWindow = new MainWindow(new Arguments(desktop.Args ?? Array.Empty<string>()));
+			desktop.MainWindow = new MainWindow(Program.Arguments);
 		}
 
 		base.OnFrameworkInitializationCompleted();

app/Desktop/Arguments.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using DHT.Utils.Logging;
 
 namespace DHT.Desktop;
@@ -6,29 +7,37 @@ namespace DHT.Desktop;
 sealed class Arguments {
 	private static readonly Log Log = Log.ForType<Arguments>();
 
-	public static Arguments Empty => new(Array.Empty<string>());
+	private const int FirstArgument = 1;
 
+	public static Arguments Empty => new (Array.Empty<string>());
+
+	public bool Console { get; }
 	public string? DatabaseFile { get; }
 	public ushort? ServerPort { get; }
 	public string? ServerToken { get; }
+	public byte? ConcurrentDownloads { get; }
 
-	public Arguments(string[] args) {
-		for (int i = 0; i < args.Length; i++) {
+	public Arguments(IReadOnlyList<string> args) {
+		for (int i = FirstArgument; i < args.Count; i++) {
 			string key = args[i];
 
 			switch (key) {
 				case "-debug":
 					Log.IsDebugEnabled = true;
 					continue;
+
+				case "-console":
+					Console = true;
+					continue;
 			}
 
 			string value;
 
-			if (i == 0 && !key.StartsWith('-')) {
+			if (i == FirstArgument && !key.StartsWith('-')) {
 				value = key;
 				key = "-db";
 			}
-			else if (i >= args.Length - 1) {
+			else if (i >= args.Count - 1) {
 				Log.Warn("Missing value for command line argument: " + key);
 				continue;
 			}
@@ -42,11 +51,11 @@ sealed class Arguments {
 					continue;
 
 				case "-port": {
-					if (ushort.TryParse(value, out var port)) {
-						ServerPort = port;
+					if (!ushort.TryParse(value, out var port)) {
+						Log.Warn("Invalid port number: " + value);
 					}
 					else {
-						Log.Warn("Invalid port number: " + value);
+						ServerPort = port;
 					}
 
 					continue;
@@ -55,6 +64,20 @@ sealed class Arguments {
 				case "-token":
 					ServerToken = value;
 					continue;
+				
+				case "-concurrentdownloads":
+					if (!ulong.TryParse(value, out var concurrentDownloads) || concurrentDownloads == 0) {
+						Log.Warn("Invalid concurrent downloads count: " + value);
+					}
+					else if (concurrentDownloads > 10) {
+						Log.Warn("Limiting concurrent downloads to 10");
+						ConcurrentDownloads = 10;
+					}
+					else {
+						ConcurrentDownloads = (byte) concurrentDownloads;
+					}
+					
+					continue;
 
 				default:
 					Log.Warn("Unknown command line argument: " + key);

app/Desktop/Common/BytesValueConverter.cs

@@ -19,17 +19,17 @@ sealed class BytesValueConverter : IValueConverter {
 		}
 	}
 
-	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 static readonly Unit[] Units = [
+		new Unit("B", decimalPlaces: 0),
+		new Unit("kB", decimalPlaces: 0),
+		new Unit("MB", decimalPlaces: 1),
+		new Unit("GB", decimalPlaces: 1),
+		new Unit("TB", decimalPlaces: 1)
+	];
 
 	private const int Scale = 1000;
 
-	private static string Convert(ulong size) {
+	public 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));

app/Desktop/Common/DatabaseGui.cs

@@ -9,6 +9,7 @@ using DHT.Desktop.Dialogs.Message;
 using DHT.Server.Database;
 using DHT.Server.Database.Exceptions;
 using DHT.Server.Database.Sqlite;
+using DHT.Server.Database.Sqlite.Schema;
 using DHT.Utils.Logging;
 
 namespace DHT.Desktop.Common;
@@ -18,9 +19,9 @@ static class DatabaseGui {
 
 	private const string DatabaseFileInitialName = "archive.dht";
 
-	private static readonly IReadOnlyList<FilePickerFileType> DatabaseFileDialogFilter = new List<FilePickerFileType> {
-		FileDialogs.CreateFilter("Discord History Tracker Database", new [] { "dht" })
-	};
+	private static readonly IReadOnlyList<FilePickerFileType> DatabaseFileDialogFilter = [
+		FileDialogs.CreateFilter("Discord History Tracker Database", ["dht"])
+	];
 
 	public static async Task<string[]> NewOpenDatabaseFilesDialog(Window window, string? suggestedDirectory) {
 		return await window.StorageProvider.OpenFiles(new FilePickerOpenOptions {
@@ -41,11 +42,11 @@ static class DatabaseGui {
 		});
 	}
 
-	public static async Task<IDatabaseFile?> TryOpenOrCreateDatabaseFromPath(string path, Window window, Func<Task<bool>> checkCanUpgradeDatabase) {
+	public static async Task<IDatabaseFile?> TryOpenOrCreateDatabaseFromPath(string path, Window window, ISchemaUpgradeCallbacks schemaUpgradeCallbacks) {
 		IDatabaseFile? file = null;
 
 		try {
-			file = await SqliteDatabaseFile.OpenOrCreate(path, checkCanUpgradeDatabase);
+			file = await SqliteDatabaseFile.OpenOrCreate(path, schemaUpgradeCallbacks);
 		} catch (InvalidDatabaseVersionException ex) {
 			await Dialog.ShowOk(window, "Database Error", "Database '" + Path.GetFileName(path) + "' appears to be corrupted (invalid version: " + ex.Version + ").");
 		} catch (DatabaseTooNewException ex) {

app/Desktop/Desktop.csproj

@@ -9,6 +9,7 @@
   <PropertyGroup>
     <OutputType>WinExe</OutputType>
     <ApplicationIcon>./Resources/icon.ico</ApplicationIcon>
+    <AvaloniaUseCompiledBindingsByDefault>true</AvaloniaUseCompiledBindingsByDefault>
     <CheckForOverflowUnderflow>true</CheckForOverflowUnderflow>
     <SatelliteResourceLanguages>en</SatelliteResourceLanguages>
   </PropertyGroup>
@@ -20,7 +21,9 @@
     <PackageReference Include="Avalonia.Desktop" Version="11.0.6" />
     <PackageReference Include="Avalonia.Diagnostics" Version="11.0.6" Condition=" '$(Configuration)' == 'Debug' " />
     <PackageReference Include="Avalonia.Fonts.Inter" Version="11.0.6" />
+    <PackageReference Include="Avalonia.ReactiveUI" Version="11.0.6" />
     <PackageReference Include="Avalonia.Themes.Fluent" Version="11.0.6" />
+    <PackageReference Include="CommunityToolkit.Mvvm" Version="999.0.0-build.0.g0d941a6a62" />
   </ItemGroup>
   
   <ItemGroup>
@@ -29,10 +32,6 @@
   
   <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>
@@ -40,11 +39,6 @@
     <EmbeddedResource Include="Resources/tracker-loader.js">
       <LogicalName>tracker-loader.js</LogicalName>
     </EmbeddedResource>
-    <EmbeddedResource Include="../Resources/Viewer/**">
-      <LogicalName>Viewer\%(RecursiveDir)%(Filename)%(Extension)</LogicalName>
-      <Link>Resources/Viewer/%(RecursiveDir)%(Filename)%(Extension)</Link>
-      <Visible>false</Visible>
-    </EmbeddedResource>
   </ItemGroup>
   
 </Project>

app/Desktop/Dialogs/CheckBox/CheckBoxDialog.axaml

@@ -5,6 +5,7 @@
         xmlns:namespace="clr-namespace:DHT.Desktop.Dialogs.CheckBox"
         mc:Ignorable="d" d:DesignWidth="500"
         x:Class="DHT.Desktop.Dialogs.CheckBox.CheckBoxDialog"
+        x:DataType="namespace:CheckBoxDialogModel"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
         Width="500" SizeToContent="Height" CanResize="False"
@@ -37,7 +38,7 @@
             <ItemsRepeater ItemsSource="{Binding Items}">
                 <ItemsRepeater.ItemTemplate>
                     <DataTemplate>
-                        <CheckBox IsChecked="{Binding Checked}">
+                        <CheckBox IsChecked="{Binding IsChecked}">
                             <Label>
                                 <TextBlock Text="{Binding Title}" TextWrapping="Wrap" />
                             </Label>

app/Desktop/Dialogs/CheckBox/CheckBoxDialogModel.cs

@@ -2,11 +2,11 @@ using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
-using DHT.Utils.Models;
+using CommunityToolkit.Mvvm.ComponentModel;
 
 namespace DHT.Desktop.Dialogs.CheckBox;
 
-class CheckBoxDialogModel : BaseModel {
+class CheckBoxDialogModel : ObservableObject {
 	public string Title { get; init; } = "";
 
 	private IReadOnlyList<CheckBoxItem> items = Array.Empty<CheckBoxItem>();
@@ -29,8 +29,8 @@ class CheckBoxDialogModel : BaseModel {
 
 	private bool pauseCheckEvents = false;
 
-	public bool AreAllSelected => Items.All(static item => item.Checked);
-	public bool AreNoneSelected => Items.All(static item => !item.Checked);
+	public bool AreAllSelected => Items.All(static item => item.IsChecked);
+	public bool AreNoneSelected => Items.All(static item => !item.IsChecked);
 
 	public void SelectAll() => SetAllChecked(true);
 	public void SelectNone() => SetAllChecked(false);
@@ -39,7 +39,7 @@ class CheckBoxDialogModel : BaseModel {
 		pauseCheckEvents = true;
 
 		foreach (var item in Items) {
-			item.Checked = isChecked;
+			item.IsChecked = isChecked;
 		}
 
 		pauseCheckEvents = false;
@@ -52,16 +52,16 @@ class CheckBoxDialogModel : BaseModel {
 	}
 
 	private void OnItemPropertyChanged(object? sender, PropertyChangedEventArgs e) {
-		if (!pauseCheckEvents && e.PropertyName == nameof(CheckBoxItem.Checked)) {
+		if (!pauseCheckEvents && e.PropertyName == nameof(CheckBoxItem.IsChecked)) {
 			UpdateBulkButtons();
 		}
 	}
 }
 
 sealed class CheckBoxDialogModel<T> : CheckBoxDialogModel {
-	public new IReadOnlyList<CheckBoxItem<T>> Items { get; }
+	private new IReadOnlyList<CheckBoxItem<T>> Items { get; }
 
-	public IEnumerable<CheckBoxItem<T>> SelectedItems => Items.Where(static item => item.Checked);
+	public IEnumerable<CheckBoxItem<T>> SelectedItems => Items.Where(static item => item.IsChecked);
 
 	public CheckBoxDialogModel(IEnumerable<CheckBoxItem<T>> items) {
 		this.Items = new List<CheckBoxItem<T>>(items);

app/Desktop/Dialogs/CheckBox/CheckBoxItem.cs

@@ -1,17 +1,13 @@
-using DHT.Utils.Models;
+using CommunityToolkit.Mvvm.ComponentModel;
 
 namespace DHT.Desktop.Dialogs.CheckBox;
 
-class CheckBoxItem : BaseModel {
+partial class CheckBoxItem : ObservableObject {
 	public string Title { get; init; } = "";
 	public object? Item { get; init; } = null;
 
+	[ObservableProperty]
 	private bool isChecked = false;
-
-	public bool Checked {
-		get => isChecked;
-		set => Change(ref isChecked, value);
-	}
 }
 
 sealed class CheckBoxItem<T> : CheckBoxItem {

app/Desktop/Dialogs/Message/MessageDialog.axaml

@@ -5,6 +5,7 @@
         xmlns:namespace="clr-namespace:DHT.Desktop.Dialogs.Message"
         mc:Ignorable="d" d:DesignWidth="500"
         x:Class="DHT.Desktop.Dialogs.Message.MessageDialog"
+        x:DataType="namespace:MessageDialogModel"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
         Width="500" SizeToContent="Height" CanResize="False"

app/Desktop/Dialogs/Progress/IProgressCallback.cs

@@ -4,4 +4,6 @@ namespace DHT.Desktop.Dialogs.Progress;
 
 interface IProgressCallback {
 	Task Update(string message, int finishedItems, int totalItems);
+	Task UpdateIndeterminate(string message);
+	Task Hide();
 }

app/Desktop/Dialogs/Progress/ProgressDialog.axaml

@@ -5,6 +5,7 @@
         xmlns:namespace="clr-namespace:DHT.Desktop.Dialogs.Progress"
         mc:Ignorable="d" d:DesignWidth="500"
         x:Class="DHT.Desktop.Dialogs.Progress.ProgressDialog"
+        x:DataType="namespace:ProgressDialogModel"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
         Opened="OnOpened"
@@ -31,12 +32,18 @@
         </Style>
     </Window.Styles>
 
-    <StackPanel Margin="20">
-        <DockPanel>
-            <TextBlock DockPanel.Dock="Right" Text="{Binding Items}" Classes="items" />
-            <TextBlock DockPanel.Dock="Left" Text="{Binding Message}" />
-        </DockPanel>
-        <ProgressBar Value="{Binding Progress}" />
-    </StackPanel>
+    <ItemsRepeater ItemsSource="{Binding Items}" Margin="0 10">
+        <ItemsRepeater.ItemTemplate>
+            <DataTemplate>
+                <StackPanel Margin="20 10" IsHitTestVisible="{Binding IsVisible}" Opacity="{Binding Opacity}">
+                    <DockPanel>
+                        <TextBlock DockPanel.Dock="Right" Text="{Binding Items}" Classes="items" />
+                        <TextBlock DockPanel.Dock="Left" Text="{Binding Message}" />
+                    </DockPanel>
+                    <ProgressBar IsIndeterminate="{Binding IsIndeterminate}" Value="{Binding Progress}" />
+                </StackPanel>
+            </DataTemplate>
+        </ItemsRepeater.ItemTemplate>
+    </ItemsRepeater>
 
 </Window>

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

@@ -7,7 +7,60 @@ namespace DHT.Desktop.Dialogs.Progress;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
 public sealed partial class ProgressDialog : Window {
+	internal static async Task Show(Window owner, string title, Func<ProgressDialog, IProgressCallback, Task> action) {
+		var taskCompletionSource = new TaskCompletionSource();
+		var dialog = new ProgressDialog();
+		
+		dialog.DataContext = new ProgressDialogModel(title, async callbacks => {
+			try {
+				await action(dialog, callbacks[0]);
+				taskCompletionSource.SetResult();
+			} catch (Exception e) {
+				taskCompletionSource.SetException(e);
+			}
+		});
+		
+		await dialog.ShowProgressDialog(owner);
+		await taskCompletionSource.Task;
+	}
+	
+	internal static async Task ShowIndeterminate(Window owner, string title, string message, Func<ProgressDialog, Task> action) {
+		var taskCompletionSource = new TaskCompletionSource();
+		var dialog = new ProgressDialog();
+		
+		dialog.DataContext = new ProgressDialogModel(title, async callbacks => {
+			await callbacks[0].UpdateIndeterminate(message);
+			try {
+				await action(dialog);
+				taskCompletionSource.SetResult();
+			} catch (Exception e) {
+				taskCompletionSource.SetException(e);
+			}
+		});
+		
+		await dialog.ShowProgressDialog(owner);
+		await taskCompletionSource.Task;
+	}
+	
+	internal static async Task<T> ShowIndeterminate<T>(Window owner, string title, string message, Func<ProgressDialog, Task<T>> action) {
+		var taskCompletionSource = new TaskCompletionSource<T>();
+		var dialog = new ProgressDialog();
+
+		dialog.DataContext = new ProgressDialogModel(title, async callbacks => {
+			await callbacks[0].UpdateIndeterminate(message);
+			try {
+				taskCompletionSource.SetResult(await action(dialog));
+			} catch (Exception e) {
+				taskCompletionSource.SetException(e);
+			}
+		});
+		
+		await dialog.ShowProgressDialog(owner);
+		return await taskCompletionSource.Task;
+	}
+
 	private bool isFinished = false;
+	private Task progressTask = Task.CompletedTask;
 
 	public ProgressDialog() {
 		InitializeComponent();
@@ -15,7 +68,8 @@ public sealed partial class ProgressDialog : Window {
 
 	public void OnOpened(object? sender, EventArgs e) {
 		if (DataContext is ProgressDialogModel model) {
-			Task.Run(model.StartTask).ContinueWith(OnFinished, TaskScheduler.FromCurrentSynchronizationContext());
+			progressTask = Task.Run(model.StartTask);
+			progressTask.ContinueWith(OnFinished, TaskScheduler.FromCurrentSynchronizationContext());
 		}
 	}
 
@@ -27,4 +81,9 @@ public sealed partial class ProgressDialog : Window {
 		isFinished = true;
 		Close();
 	}
+
+	public async Task ShowProgressDialog(Window owner) {
+		await ShowDialog(owner);
+		await progressTask;
+	}
 }

app/Desktop/Dialogs/Progress/ProgressDialogModel.cs

@@ -1,65 +1,63 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using System.Threading.Tasks;
 using Avalonia.Threading;
 using DHT.Desktop.Common;
-using DHT.Utils.Models;
 
 namespace DHT.Desktop.Dialogs.Progress;
 
-sealed class ProgressDialogModel : BaseModel {
+sealed class ProgressDialogModel {
 	public string Title { get; init; } = "";
 
-	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);
-	}
+	public IReadOnlyList<ProgressItem> Items { get; } = Array.Empty<ProgressItem>();
 
 	private readonly TaskRunner? task;
 
 	[Obsolete("Designer")]
 	public ProgressDialogModel() {}
 
-	public ProgressDialogModel(TaskRunner task) {
+	public ProgressDialogModel(string title, TaskRunner task, int progressItems = 1) {
+		this.Title = title;
 		this.task = task;
+		this.Items = Enumerable.Range(0, progressItems).Select(static _ => new ProgressItem()).ToArray();
 	}
 
 	internal async Task StartTask() {
 		if (task != null) {
-			await task(new Callback(this));
+			await task(Items.Select(static item => new Callback(item)).ToArray());
 		}
 	}
 
-	public delegate Task TaskRunner(IProgressCallback callback);
+	public delegate Task TaskRunner(IReadOnlyList<IProgressCallback> callbacks);
 
 	private sealed class Callback : IProgressCallback {
-		private readonly ProgressDialogModel model;
+		private readonly ProgressItem item;
 
-		public Callback(ProgressDialogModel model) {
-			this.model = model;
+		public Callback(ProgressItem item) {
+			this.item = item;
 		}
 
-		async Task IProgressCallback.Update(string message, int finishedItems, int totalItems) {
+		public async Task 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;
+				item.Message = message;
+				item.Items = totalItems == 0 ? string.Empty : finishedItems.Format() + " / " + totalItems.Format();
+				item.Progress = totalItems == 0 ? 0 : 100 * finishedItems / totalItems;
+				item.IsIndeterminate = false;
 			});
 		}
+
+		public async Task UpdateIndeterminate(string message) {
+			await Dispatcher.UIThread.InvokeAsync(() => {
+				item.Message = message;
+				item.Items = string.Empty;
+				item.Progress = 0;
+				item.IsIndeterminate = true;
+			});
+		}
+
+		public Task Hide() {
+			return Update(string.Empty, 0, 0);
+		}
 	}
 }

app/Desktop/Dialogs/Progress/ProgressItem.cs

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

app/Desktop/Dialogs/TextBox/TextBoxDialog.axaml

@@ -5,6 +5,7 @@
         xmlns:namespace="clr-namespace:DHT.Desktop.Dialogs.TextBox"
         mc:Ignorable="d" d:DesignWidth="500"
         x:Class="DHT.Desktop.Dialogs.TextBox.TextBoxDialog"
+        x:DataType="namespace:TextBoxDialogModel"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
         Width="500" SizeToContent="Height" CanResize="False"

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

@@ -3,7 +3,7 @@ using Avalonia.Controls;
 using Avalonia.Interactivity;
 using DHT.Desktop.Dialogs.Message;
 
-namespace DHT.Desktop.Dialogs.TextBox; 
+namespace DHT.Desktop.Dialogs.TextBox;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
 public sealed partial class TextBoxDialog : Window {

app/Desktop/Dialogs/TextBox/TextBoxDialogModel.cs

@@ -2,11 +2,11 @@ using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
-using DHT.Utils.Models;
+using CommunityToolkit.Mvvm.ComponentModel;
 
-namespace DHT.Desktop.Dialogs.TextBox; 
+namespace DHT.Desktop.Dialogs.TextBox;
 
-class TextBoxDialogModel : BaseModel {
+class TextBoxDialogModel : ObservableObject {
 	public string Title { get; init; } = "";
 	public string Description { get; init; } = "";
 
@@ -36,7 +36,7 @@ class TextBoxDialogModel : BaseModel {
 }
 
 sealed class TextBoxDialogModel<T> : TextBoxDialogModel {
-	public new IReadOnlyList<TextBoxItem<T>> Items { get; }
+	private new IReadOnlyList<TextBoxItem<T>> Items { get; }
 
 	public IEnumerable<TextBoxItem<T>> ValidItems => Items.Where(static item => item.IsValid);
 

app/Desktop/Dialogs/TextBox/TextBoxItem.cs

@@ -1,11 +1,11 @@
 using System;
 using System.Collections;
 using System.ComponentModel;
-using DHT.Utils.Models;
+using CommunityToolkit.Mvvm.ComponentModel;
 
-namespace DHT.Desktop.Dialogs.TextBox; 
+namespace DHT.Desktop.Dialogs.TextBox;
 
-class TextBoxItem : BaseModel, INotifyDataErrorInfo {
+class TextBoxItem : ObservableObject, INotifyDataErrorInfo {
 	public string Title { get; init; } = "";
 	public object? Item { get; init; } = null;
 		
@@ -17,7 +17,7 @@ class TextBoxItem : BaseModel, INotifyDataErrorInfo {
 	public string Value {
 		get => this.value;
 		set {
-			Change(ref this.value, value);
+			SetProperty(ref this.value, value);
 			ErrorsChanged?.Invoke(this, new DataErrorsChangedEventArgs(nameof(Value)));
 		}
 	}

app/Desktop/Discord/DiscordAppSettings.cs

@@ -1,9 +1,9 @@
 using System;
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Text.Json;
+using System.Text.Json.Nodes;
 using System.Threading.Tasks;
 using DHT.Utils.Logging;
 using static System.Environment.SpecialFolder;
@@ -39,7 +39,8 @@ static class DiscordAppSettings {
 
 	public static async Task<bool?> AreDevToolsEnabled() {
 		try {
-			return AreDevToolsEnabled(await ReadSettingsJson());
+			var settingsJson = await ReadSettingsJson();
+			return AreDevToolsEnabled(settingsJson);
 		} catch (Exception e) {
 			Log.Error("Cannot read settings file.");
 			Log.Error(e);
@@ -47,12 +48,12 @@ static class DiscordAppSettings {
 		}
 	}
 
-	private static bool AreDevToolsEnabled(Dictionary<string, object?> json) {
-		return json.TryGetValue(JsonKeyDevTools, out var value) && value is JsonElement { ValueKind: JsonValueKind.True };
+	private static bool AreDevToolsEnabled(JsonObject json) {
+		return json.TryGetPropertyValue(JsonKeyDevTools, out var node) && node?.GetValueKind() == JsonValueKind.True;
 	}
 
 	public static async Task<SettingsJsonResult> ConfigureDevTools(bool enable) {
-		Dictionary<string, object?> json;
+		JsonObject json;
 
 		try {
 			json = await ReadSettingsJson();
@@ -109,13 +110,13 @@ static class DiscordAppSettings {
 		return SettingsJsonResult.Success;
 	}
 
-	private static async Task<Dictionary<string, object?>> ReadSettingsJson() {
+	private static async Task<JsonObject> 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();
+		return await JsonSerializer.DeserializeAsync(stream, DiscordAppSettingsJsonContext.Default.JsonObject) ?? throw new JsonException();
 	}
 
-	private static async Task WriteSettingsJson(Dictionary<string, object?> json) {
+	private static async Task WriteSettingsJson(JsonObject json) {
 		await using var stream = new FileStream(JsonFilePath, FileMode.Truncate, FileAccess.Write, FileShare.None);
-		await JsonSerializer.SerializeAsync(stream, json, new JsonSerializerOptions { WriteIndented = true });
+		await JsonSerializer.SerializeAsync(stream, json, DiscordAppSettingsJsonContext.Default.JsonObject);
 	}
 }

app/Desktop/Discord/DiscordAppSettingsJsonContext.cs

@@ -0,0 +1,8 @@
+using System.Text.Json.Nodes;
+using System.Text.Json.Serialization;
+
+namespace DHT.Desktop.Discord;
+
+[JsonSourceGenerationOptions(GenerationMode = JsonSourceGenerationMode.Default, WriteIndented = true)]
+[JsonSerializable(typeof(JsonObject))]
+sealed partial class DiscordAppSettingsJsonContext : JsonSerializerContext;

app/Desktop/Main/AboutWindow.axaml

@@ -5,6 +5,7 @@
         xmlns:main="clr-namespace:DHT.Desktop.Main"
         mc:Ignorable="d" d:DesignWidth="480" d:DesignHeight="295"
         x:Class="DHT.Desktop.Main.AboutWindow"
+        x:DataType="main:AboutWindowModel"
         Title="About Discord History Tracker"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
         Width="480" Height="295" CanResize="False"

app/Desktop/Main/Controls/AttachmentFilterPanelModel.cs

@@ -1,129 +0,0 @@
-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/DownloadItemFilterPanel.axaml

@@ -4,10 +4,11 @@
              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">
+             x:Class="DHT.Desktop.Main.Controls.DownloadItemFilterPanel"
+             x:DataType="controls:DownloadItemFilterPanelModel">
 
     <Design.DataContext>
-        <controls:AttachmentFilterPanelModel />
+        <controls:DownloadItemFilterPanelModel />
     </Design.DataContext>
 
     <UserControl.Styles>

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

@@ -4,8 +4,8 @@ using Avalonia.Controls;
 namespace DHT.Desktop.Main.Controls;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
-public sealed partial class AttachmentFilterPanel : UserControl {
-	public AttachmentFilterPanel() {
+public sealed partial class DownloadItemFilterPanel : UserControl {
+	public DownloadItemFilterPanel() {
 		InitializeComponent();
 	}
 }

app/Desktop/Main/Controls/DownloadItemFilterPanelModel.cs

@@ -0,0 +1,124 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Reactive.Linq;
+using System.Threading.Tasks;
+using Avalonia.ReactiveUI;
+using CommunityToolkit.Mvvm.ComponentModel;
+using DHT.Desktop.Common;
+using DHT.Server;
+using DHT.Server.Data.Filters;
+using DHT.Utils.Tasks;
+
+namespace DHT.Desktop.Main.Controls;
+
+sealed partial class DownloadItemFilterPanelModel : ObservableObject, IDisposable {
+	public sealed record Unit(string Name, uint Scale);
+
+	private static readonly Unit[] AllUnits = [
+		new Unit("B", 1),
+		new Unit("kB", 1024),
+		new Unit("MB", 1024 * 1024)
+	];
+
+	private static readonly HashSet<string> FilterProperties = [
+		nameof(LimitSize),
+		nameof(MaximumSize),
+		nameof(MaximumSizeUnit)
+	];
+
+	public string FilterStatisticsText { get; private set; } = "";
+
+	[ObservableProperty]
+	private bool limitSize = false;
+	
+	[ObservableProperty]
+	private ulong maximumSize = 0L;
+	
+	[ObservableProperty]
+	private Unit maximumSizeUnit = AllUnits[0];
+
+	public IEnumerable<Unit> Units => AllUnits;
+
+	private readonly State state;
+	private readonly string verb;
+
+	private readonly RestartableTask<long> downloadItemCountTask;
+	private long? matchingItemCount;
+	
+	private readonly IDisposable downloadItemCountSubscription;
+	private long? totalItemCount;
+
+	[Obsolete("Designer")]
+	public DownloadItemFilterPanelModel() : this(State.Dummy) {}
+
+	public DownloadItemFilterPanelModel(State state, string verb = "Matches") {
+		this.state = state;
+		this.verb = verb;
+
+		this.downloadItemCountTask = new RestartableTask<long>(SetMatchingCount, TaskScheduler.FromCurrentSynchronizationContext());
+		this.downloadItemCountSubscription = state.Db.Downloads.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnDownloadItemCountChanged);
+
+		UpdateFilterStatistics();
+
+		PropertyChanged += OnPropertyChanged;
+	}
+
+	public void Dispose() {
+		downloadItemCountTask.Cancel();
+		downloadItemCountSubscription.Dispose();
+	}
+
+	private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
+		if (e.PropertyName != null && FilterProperties.Contains(e.PropertyName)) {
+			UpdateFilterStatistics();
+		}
+	}
+	
+	private void OnDownloadItemCountChanged(long newItemCount) {
+		totalItemCount = newItemCount;
+		UpdateFilterStatistics();
+	}
+	
+
+	private void UpdateFilterStatistics() {
+		var filter = CreateFilter();
+		if (filter.IsEmpty) {
+			downloadItemCountTask.Cancel();
+			matchingItemCount = totalItemCount;
+			UpdateFilterStatisticsText();
+		}
+		else {
+			matchingItemCount = null;
+			UpdateFilterStatisticsText();
+			downloadItemCountTask.Restart(cancellationToken => state.Db.Downloads.Count(filter, cancellationToken));
+		}
+	}
+
+	private void SetMatchingCount(long matchingAttachmentCount) {
+		this.matchingItemCount = matchingAttachmentCount;
+		UpdateFilterStatisticsText();
+	}
+
+	private void UpdateFilterStatisticsText() {
+		var matchingItemCountStr = matchingItemCount?.Format() ?? "(...)";
+		var totalItemCountStr = totalItemCount?.Format() ?? "(...)";
+
+		FilterStatisticsText = verb + " " + matchingItemCountStr + " out of " + totalItemCountStr + " file" + (totalItemCount is null or 1 ? "." : "s.");
+		OnPropertyChanged(nameof(FilterStatisticsText));
+	}
+
+	public DownloadItemFilter CreateFilter() {
+		DownloadItemFilter 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/MessageFilterPanel.axaml

@@ -4,7 +4,8 @@
              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">
+             x:Class="DHT.Desktop.Main.Controls.MessageFilterPanel"
+             x:DataType="controls:MessageFilterPanelModel">
 
     <Design.DataContext>
         <controls:MessageFilterPanelModel />

app/Desktop/Main/Controls/MessageFilterPanelModel.cs

@@ -2,22 +2,25 @@ using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Linq;
+using System.Reactive.Linq;
 using System.Text;
 using System.Threading.Tasks;
 using Avalonia.Controls;
+using Avalonia.ReactiveUI;
+using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.CheckBox;
 using DHT.Desktop.Dialogs.Message;
+using DHT.Desktop.Dialogs.Progress;
+using DHT.Server;
 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 () {
+sealed partial class MessageFilterPanelModel : ObservableObject, IDisposable {
+	private static readonly HashSet<string> FilterProperties = [
 		nameof(FilterByDate),
 		nameof(StartDate),
 		nameof(EndDate),
@@ -25,7 +28,7 @@ sealed class MessageFilterPanelModel : BaseModel, IDisposable {
 		nameof(IncludedChannels),
 		nameof(FilterByUser),
 		nameof(IncludedUsers)
-	};
+	];
 
 	public string FilterStatisticsText { get; private set; } = "";
 
@@ -33,91 +36,76 @@ sealed class MessageFilterPanelModel : BaseModel, IDisposable {
 
 	public bool HasAnyFilters => FilterByDate || FilterByChannel || FilterByUser;
 
+	[ObservableProperty]
 	private bool filterByDate = false;
+
+	[ObservableProperty]
 	private DateTime? startDate = null;
+
+	[ObservableProperty]
 	private DateTime? endDate = null;
+
+	[ObservableProperty]
 	private bool filterByChannel = false;
+
+	[ObservableProperty]
 	private HashSet<ulong>? includedChannels = null;
+
+	[ObservableProperty]
 	private bool filterByUser = false;
+
+	[ObservableProperty]
 	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);
-	}
-
+	[ObservableProperty]
 	private string channelFilterLabel = "";
 
-	public string ChannelFilterLabel {
-		get => channelFilterLabel;
-		set => Change(ref channelFilterLabel, value);
-	}
-
+	[ObservableProperty]
 	private string userFilterLabel = "";
 
-	public string UserFilterLabel {
-		get => userFilterLabel;
-		set => Change(ref userFilterLabel, value);
-	}
-
 	private readonly Window window;
-	private readonly IDatabaseFile db;
+	private readonly State state;
 	private readonly string verb;
 
-	private readonly AsyncValueComputer<long> exportedMessageCountComputer;
+	private readonly RestartableTask<long> exportedMessageCountTask;
 	private long? exportedMessageCount;
+	
+	private readonly IDisposable messageCountSubscription;
 	private long? totalMessageCount;
+	
+	private readonly IDisposable channelCountSubscription;
+	private long? totalChannelCount;
+	
+	private readonly IDisposable userCountSubscription;
+	private long? totalUserCount;
 
 	[Obsolete("Designer")]
-	public MessageFilterPanelModel() : this(null!, DummyDatabaseFile.Instance) {}
+	public MessageFilterPanelModel() : this(null!, State.Dummy) {}
 
-	public MessageFilterPanelModel(Window window, IDatabaseFile db, string verb = "Matches") {
+	public MessageFilterPanelModel(Window window, State state, string verb = "Matches") {
 		this.window = window;
-		this.db = db;
+		this.state = state;
 		this.verb = verb;
 
-		this.exportedMessageCountComputer = AsyncValueComputer<long>.WithResultProcessor(SetExportedMessageCount).Build();
+		this.exportedMessageCountTask = new RestartableTask<long>(SetExportedMessageCount, TaskScheduler.FromCurrentSynchronizationContext());
+		
+		this.messageCountSubscription = state.Db.Messages.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnMessageCountChanged);
+		this.channelCountSubscription = state.Db.Channels.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnChannelCountChanged);
+		this.userCountSubscription = state.Db.Users.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnUserCountChanged);
 
 		UpdateFilterStatistics();
 		UpdateChannelFilterLabel();
 		UpdateUserFilterLabel();
-
+		
 		PropertyChanged += OnPropertyChanged;
-		db.Statistics.PropertyChanged += OnDbStatisticsChanged;
 	}
 
 	public void Dispose() {
-		db.Statistics.PropertyChanged -= OnDbStatisticsChanged;
+		exportedMessageCountTask.Cancel();
+		
+		messageCountSubscription.Dispose();
+		channelCountSubscription.Dispose();
+		userCountSubscription.Dispose();
 	}
 
 	private void OnPropertyChanged(object? sender, PropertyChangedEventArgs e) {
@@ -134,30 +122,54 @@ sealed class MessageFilterPanelModel : BaseModel, IDisposable {
 		}
 	}
 
-	private void OnDbStatisticsChanged(object? sender, PropertyChangedEventArgs e) {
-		if (e.PropertyName == nameof(DatabaseStatistics.TotalMessages)) {
-			totalMessageCount = db.Statistics.TotalMessages;
-			UpdateFilterStatistics();
+	private void OnMessageCountChanged(long newMessageCount) {
+		totalMessageCount = newMessageCount;
+		UpdateFilterStatistics();
+	}
+
+	private void OnChannelCountChanged(long newChannelCount) {
+		totalChannelCount = newChannelCount;
+		UpdateChannelFilterLabel();
+	}
+	
+	private void OnUserCountChanged(long newUserCount) {
+		totalUserCount = newUserCount;
+		UpdateUserFilterLabel();
+	}
+
+	private void UpdateChannelFilterLabel() {
+		if (totalChannelCount.HasValue) {
+			long total = totalChannelCount.Value;
+			long included = FilterByChannel && IncludedChannels != null ? IncludedChannels.Count : total;
+			ChannelFilterLabel = "Selected " + included.Format() + " / " + total.Pluralize("channel") + ".";
 		}
-		else if (e.PropertyName == nameof(DatabaseStatistics.TotalChannels)) {
-			UpdateChannelFilterLabel();
+		else {
+			ChannelFilterLabel = "Loading...";
 		}
-		else if (e.PropertyName == nameof(DatabaseStatistics.TotalUsers)) {
-			UpdateUserFilterLabel();
+	}
+
+	private void UpdateUserFilterLabel() {
+		if (totalUserCount.HasValue) {
+			long total = totalUserCount.Value;
+			long included = FilterByUser && IncludedUsers != null ? IncludedUsers.Count : total;
+			UserFilterLabel = "Selected " + included.Format() + " / " + total.Pluralize("user") + ".";
+		}
+		else {
+			UserFilterLabel = "Loading...";
 		}
 	}
 
 	private void UpdateFilterStatistics() {
 		var filter = CreateFilter();
 		if (filter.IsEmpty) {
-			exportedMessageCountComputer.Cancel();
+			exportedMessageCountTask.Cancel();
 			exportedMessageCount = totalMessageCount;
 			UpdateFilterStatisticsText();
 		}
 		else {
 			exportedMessageCount = null;
 			UpdateFilterStatisticsText();
-			exportedMessageCountComputer.Compute(() => db.CountMessages(filter));
+			exportedMessageCountTask.Restart(cancellationToken => state.Db.Messages.Count(filter, cancellationToken));
 		}
 	}
 
@@ -174,103 +186,98 @@ sealed class MessageFilterPanelModel : BaseModel, IDisposable {
 		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;
+	public async Task OpenChannelFilterDialog() {
+		async Task<List<CheckBoxItem<ulong>>> PrepareChannelItems(ProgressDialog dialog) {
+			var items = new List<CheckBoxItem<ulong>>();
+			var servers = await state.Db.Servers.Get().ToDictionaryAsync(static server => server.Id);
 
-		foreach (var channel in db.GetAllChannels()) {
-			var channelId = channel.Id;
-			var channelName = channel.Name;
+			await foreach (var channel in state.Db.Channels.Get()) {
+				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;
+				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("] ");
+					titleBuilder.Append('[')
+					            .Append(ServerTypes.ToString(serverType))
+					            .Append("] ");
 
-				if (serverType == ServerType.DirectMessage) {
-					titleBuilder.Append(channelName);
+					if (serverType == ServerType.DirectMessage) {
+						titleBuilder.Append(channelName);
+					}
+					else {
+						titleBuilder.Append(server.Name)
+						            .Append(" - ")
+						            .Append(channelName);
+					}
+
+					title = titleBuilder.ToString();
 				}
 				else {
-					titleBuilder.Append(server.Name)
-					            .Append(" - ")
-					            .Append(channelName);
+					title = channelName;
 				}
 
-				title = titleBuilder.ToString();
-			}
-			else {
-				title = channelName;
+				items.Add(new CheckBoxItem<ulong>(channelId) {
+					Title = title,
+					IsChecked = IncludedChannels == null || IncludedChannels.Contains(channelId)
+				});
 			}
 
-			items.Add(new CheckBoxItem<ulong>(channelId) {
-				Title = title,
-				Checked = included.Contains(channelId)
-			});
+			return items;
 		}
 
-		var result = await OpenIdFilterDialog(window, "Included Channels", items);
+		const string Title = "Included Channels";
+
+		List<CheckBoxItem<ulong>> items;
+		try {
+			items = await ProgressDialog.ShowIndeterminate(window, Title, "Loading channels...", PrepareChannelItems);
+		} catch (Exception e) {
+			await Dialog.ShowOk(window, Title, "Error loading channels: " + e.Message);
+			return;
+		}
+
+		var result = await OpenIdFilterDialog(Title, items);
 		if (result != null) {
 			IncludedChannels = result;
 		}
 	}
 
-	public async void OpenUserFilterDialog() {
-		var items = new List<CheckBoxItem<ulong>>();
-		var included = IncludedUsers;
+	public async Task OpenUserFilterDialog() {
+		async Task<List<CheckBoxItem<ulong>>> PrepareUserItems(ProgressDialog dialog) {
+			var checkBoxItems = new List<CheckBoxItem<ulong>>();
 
-		foreach (var user in db.GetAllUsers()) {
-			var name = user.Name;
-			var discriminator = user.Discriminator;
+			await foreach (var user in state.Db.Users.Get()) {
+				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)
-			});
+				checkBoxItems.Add(new CheckBoxItem<ulong>(user.Id) {
+					Title = discriminator == null ? name : name + " #" + discriminator,
+					IsChecked = IncludedUsers == null || IncludedUsers.Contains(user.Id)
+				});
+			}
+
+			return checkBoxItems;
 		}
 
-		var result = await OpenIdFilterDialog(window, "Included Users", items);
+		const string Title = "Included Users";
+
+		List<CheckBoxItem<ulong>> items;
+		try {
+			items = await ProgressDialog.ShowIndeterminate(window, Title, "Loading users...", PrepareUserItems);
+		} catch (Exception e) {
+			await Dialog.ShowOk(window, Title, "Error loading users: " + e.Message);
+			return;
+		}
+
+		var result = await OpenIdFilterDialog(Title, 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) {
+	private async Task<HashSet<ulong>?> OpenIdFilterDialog(string title, List<CheckBoxItem<ulong>> items) {
 		items.Sort(static (item1, item2) => item1.Title.CompareTo(item2.Title));
 
 		var model = new CheckBoxDialogModel<ulong>(items) {
@@ -282,4 +289,23 @@ sealed class MessageFilterPanelModel : BaseModel, IDisposable {
 
 		return result == DialogResult.OkCancel.Ok ? model.SelectedItems.Select(static item => item.Item).ToHashSet() : null;
 	}
+
+	public MessageFilter CreateFilter() {
+		MessageFilter filter = new ();
+
+		if (FilterByDate) {
+			filter.StartDate = StartDate;
+			filter.EndDate = EndDate?.AddDays(1).AddMilliseconds(-1);
+		}
+
+		if (FilterByChannel && IncludedChannels != null) {
+			filter.ChannelIds = new HashSet<ulong>(IncludedChannels);
+		}
+
+		if (FilterByUser && IncludedUsers != null) {
+			filter.UserIds = new HashSet<ulong>(IncludedUsers);
+		}
+
+		return filter;
+	}
 }

app/Desktop/Main/Controls/ServerConfigurationPanel.axaml

@@ -4,7 +4,8 @@
              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.ServerConfigurationPanel">
+             x:Class="DHT.Desktop.Main.Controls.ServerConfigurationPanel"
+             x:DataType="controls:ServerConfigurationPanelModel">
 
     <Design.DataContext>
         <controls:ServerConfigurationPanelModel />

app/Desktop/Main/Controls/ServerConfigurationPanelModel.cs

@@ -1,96 +1,95 @@
 using System;
+using System.Threading.Tasks;
 using Avalonia.Controls;
+using Avalonia.Threading;
+using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Server;
-using DHT.Server.Database;
+using DHT.Server;
 using DHT.Server.Service;
-using DHT.Utils.Models;
+using DHT.Utils.Logging;
 
 namespace DHT.Desktop.Main.Controls;
 
-sealed class ServerConfigurationPanelModel : BaseModel, IDisposable {
+sealed partial class ServerConfigurationPanelModel : ObservableObject, IDisposable {
+	private static readonly Log Log = Log.ForType<ServerConfigurationPanelModel>();
+	
+	[ObservableProperty]
+	[NotifyPropertyChangedFor(nameof(HasMadeChanges))]
 	private string inputPort;
 
-	public string InputPort {
-		get => inputPort;
-		set {
-			Change(ref inputPort, value);
-			OnPropertyChanged(nameof(HasMadeChanges));
-		}
-	}
-
+	[ObservableProperty]
+	[NotifyPropertyChangedFor(nameof(HasMadeChanges))]
 	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;
+	public bool HasMadeChanges => ServerConfiguration.Port.ToString() != InputPort || ServerConfiguration.Token != InputToken;
 
+	[ObservableProperty(Setter = Access.Private)]
 	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;
+	public string ToggleServerButtonText => server.IsRunning ? "Stop Server" : "Start Server";
 
 	private readonly Window window;
-	private readonly ServerManager serverManager;
+	private readonly ServerManager server;
 
 	[Obsolete("Designer")]
-	public ServerConfigurationPanelModel() : this(null!, new ServerManager(DummyDatabaseFile.Instance)) {}
+	public ServerConfigurationPanelModel() : this(null!, State.Dummy) {}
 
-	public ServerConfigurationPanelModel(Window window, ServerManager serverManager) {
+	public ServerConfigurationPanelModel(Window window, State state) {
 		this.window = window;
-		this.serverManager = serverManager;
-		this.inputPort = ServerManager.Port.ToString();
-		this.inputToken = ServerManager.Token;
-	}
-
-	public void Initialize() {
-		ServerLauncher.ServerStatusChanged += ServerLauncherOnServerStatusChanged;
+		this.server = state.Server;
+		this.inputPort = ServerConfiguration.Port.ToString();
+		this.inputToken = ServerConfiguration.Token;
+		
+		server.StatusChanged += OnServerStatusChanged;
 	}
 
 	public void Dispose() {
-		ServerLauncher.ServerStatusChanged -= ServerLauncherOnServerStatusChanged;
+		server.StatusChanged -= OnServerStatusChanged;
 	}
 
-	private void ServerLauncherOnServerStatusChanged(object? sender, EventArgs e) {
-		ServerStatusChanged?.Invoke(this, serverManager.IsRunning ? StatusBarModel.Status.Ready : StatusBarModel.Status.Stopped);
+	private void OnServerStatusChanged(object? sender, ServerManager.Status e) {
+		Dispatcher.UIThread.InvokeAsync(UpdateServerStatus);
+	}
+
+	private void UpdateServerStatus() {
 		OnPropertyChanged(nameof(ToggleServerButtonText));
+	}
+
+	private async Task StartServer() {
+		IsToggleServerButtonEnabled = false;
+		
+		try {
+			await server.Start(ServerConfiguration.Port, ServerConfiguration.Token);
+		} catch (Exception e) {
+			Log.Error(e);
+			await Dialog.ShowOk(window, "Internal Server Error", e.Message);
+		}
+		
+		UpdateServerStatus();
 		IsToggleServerButtonEnabled = true;
 	}
 
-	private void BeforeServerStart() {
+	private async Task StopServer() {
 		IsToggleServerButtonEnabled = false;
-		ServerStatusChanged?.Invoke(this, StatusBarModel.Status.Starting);
+		
+		try {
+			await server.Stop();
+		} catch (Exception e) {
+			Log.Error(e);
+			await Dialog.ShowOk(window, "Internal Server Error", e.Message);
+		}
+		
+		UpdateServerStatus();
+		IsToggleServerButtonEnabled = true;
 	}
 
-	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();
+	public async Task OnClickToggleServerButton() {
+		if (server.IsRunning) {
+			await StopServer();
 		}
 		else {
-			StartServer();
+			await StartServer();
 		}
 	}
 
@@ -98,19 +97,22 @@ sealed class ServerConfigurationPanelModel : BaseModel, IDisposable {
 		InputToken = ServerUtils.GenerateRandomToken(20);
 	}
 
-	public async void OnClickApplyChanges() {
+	public async Task 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);
+		ServerConfiguration.Port = port;
+		ServerConfiguration.Token = inputToken;
+		
 		OnPropertyChanged(nameof(HasMadeChanges));
+		
+		await StartServer();
 	}
 
 	public void OnClickCancelChanges() {
-		InputPort = ServerManager.Port.ToString();
-		InputToken = ServerManager.Token;
+		InputPort = ServerConfiguration.Port.ToString();
+		InputToken = ServerConfiguration.Token;
 	}
 }

app/Desktop/Main/Controls/StatusBar.axaml

@@ -4,7 +4,8 @@
              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.StatusBar">
+             x:Class="DHT.Desktop.Main.Controls.StatusBar"
+             x:DataType="controls:StatusBarModel">
 
     <Design.DataContext>
         <controls:StatusBarModel />
@@ -39,22 +40,22 @@
     <StackPanel Orientation="Horizontal" Margin="6 3">
         <StackPanel Orientation="Vertical" Width="65">
             <TextBlock Classes="label">Status</TextBlock>
-            <TextBlock FontSize="12" Margin="0 3 0 0" Text="{Binding StatusText}" />
+            <TextBlock FontSize="12" Margin="0 3 0 0" Text="{Binding ServerStatusText}" />
         </StackPanel>
         <Rectangle />
         <StackPanel Orientation="Vertical">
             <TextBlock Classes="label">Servers</TextBlock>
-            <TextBlock Classes="value" Text="{Binding DatabaseStatistics.TotalServers, Converter={StaticResource NumberValueConverter}}" />
+            <TextBlock Classes="value" Text="{Binding ServerCount, Mode=OneWay, Converter={StaticResource NumberValueConverter}}" />
         </StackPanel>
         <Rectangle />
         <StackPanel Orientation="Vertical">
             <TextBlock Classes="label">Channels</TextBlock>
-            <TextBlock Classes="value" Text="{Binding DatabaseStatistics.TotalChannels, Converter={StaticResource NumberValueConverter}}" />
+            <TextBlock Classes="value" Text="{Binding ChannelCount, Mode=OneWay, Converter={StaticResource NumberValueConverter}}" />
         </StackPanel>
         <Rectangle />
         <StackPanel Orientation="Vertical">
             <TextBlock Classes="label">Messages</TextBlock>
-            <TextBlock Classes="value" Text="{Binding DatabaseStatistics.TotalMessages, Converter={StaticResource NumberValueConverter}}" />
+            <TextBlock Classes="value" Text="{Binding MessageCount, Mode=OneWay, Converter={StaticResource NumberValueConverter}}" />
         </StackPanel>
     </StackPanel>
 

app/Desktop/Main/Controls/StatusBarModel.cs

@@ -1,45 +1,63 @@
 using System;
-using DHT.Server.Database;
-using DHT.Utils.Models;
+using System.Reactive.Linq;
+using Avalonia.ReactiveUI;
+using Avalonia.Threading;
+using CommunityToolkit.Mvvm.ComponentModel;
+using DHT.Server;
+using DHT.Server.Service;
 
 namespace DHT.Desktop.Main.Controls;
 
-sealed class StatusBarModel : BaseModel {
-	public DatabaseStatistics DatabaseStatistics { get; }
+sealed partial class StatusBarModel : ObservableObject, IDisposable {
+	[ObservableProperty(Setter = Access.Private)]
+	private long? serverCount;
+	
+	[ObservableProperty(Setter = Access.Private)]
+	private long? channelCount;
+	
+	[ObservableProperty(Setter = Access.Private)]
+	private long? messageCount;
 
-	private Status status = Status.Stopped;
+	[ObservableProperty(Setter = Access.Private)]
+	[NotifyPropertyChangedFor(nameof(ServerStatusText))]
+	private ServerManager.Status serverStatus;
 
-	public Status CurrentStatus {
-		get => status;
-		set {
-			status = value;
-			OnPropertyChanged(nameof(StatusText));
-		}
-	}
+	public string ServerStatusText => serverStatus switch {
+		ServerManager.Status.Starting => "STARTING",
+		ServerManager.Status.Started  => "READY",
+		ServerManager.Status.Stopping => "STOPPING",
+		ServerManager.Status.Stopped  => "STOPPED",
+		_                             => ""
+	};
 
-	public string StatusText {
-		get {
-			return CurrentStatus switch {
-				Status.Starting => "STARTING",
-				Status.Ready    => "READY",
-				Status.Stopping => "STOPPING",
-				Status.Stopped  => "STOPPED",
-				_               => ""
-			};
-		}
-	}
+	private readonly State state;
+	private readonly IDisposable serverCountSubscription;
+	private readonly IDisposable channelCountSubscription;
+	private readonly IDisposable messageCountSubscription;
 
 	[Obsolete("Designer")]
-	public StatusBarModel() : this(new DatabaseStatistics()) {}
+	public StatusBarModel() : this(State.Dummy) {}
 
-	public StatusBarModel(DatabaseStatistics databaseStatistics) {
-		this.DatabaseStatistics = databaseStatistics;
+	public StatusBarModel(State state) {
+		this.state = state;
+		
+		serverCountSubscription = state.Db.Servers.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(newServerCount => ServerCount = newServerCount);
+		channelCountSubscription = state.Db.Channels.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(newChannelCount => ChannelCount = newChannelCount);
+		messageCountSubscription = state.Db.Messages.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(newMessageCount => MessageCount = newMessageCount);
+
+		state.Server.StatusChanged += OnServerStatusChanged;
+		serverStatus = state.Server.IsRunning ? ServerManager.Status.Started : ServerManager.Status.Stopped;
 	}
 
-	public enum Status {
-		Starting,
-		Ready,
-		Stopping,
-		Stopped
+	public void Dispose() {
+		serverCountSubscription.Dispose();
+		channelCountSubscription.Dispose();
+		messageCountSubscription.Dispose();
+		
+		state.Server.StatusChanged -= OnServerStatusChanged;
+	}
+
+	private void OnServerStatusChanged(object? sender, ServerManager.Status e) {
+		Dispatcher.UIThread.InvokeAsync(() => ServerStatus = e);
 	}
 }

app/Desktop/Main/MainWindow.axaml

@@ -5,12 +5,13 @@
         xmlns:main="clr-namespace:DHT.Desktop.Main"
         mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
         x:Class="DHT.Desktop.Main.MainWindow"
+        x:DataType="main:MainWindowModel"
         Title="{Binding Title}"
         Icon="avares://DiscordHistoryTracker/Resources/icon.ico"
-        Width="800" Height="500"
+        Width="820" Height="520"
         MinWidth="520" MinHeight="300"
         WindowStartupLocation="CenterScreen"
-        Closed="OnClosed">
+        Closing="OnClosing">
 
     <Design.DataContext>
         <main:MainWindowModel />

app/Desktop/Main/MainWindow.axaml.cs

@@ -1,14 +1,16 @@
 using System;
 using System.Diagnostics.CodeAnalysis;
-using System.IO;
+using System.Threading.Tasks;
 using Avalonia.Controls;
-using DHT.Desktop.Main.Pages;
+using DHT.Utils.Logging;
 using JetBrains.Annotations;
 
 namespace DHT.Desktop.Main;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
 public sealed partial class MainWindow : Window {
+	private static readonly Log Log = Log.ForType<MainWindow>();
+	
 	[UsedImplicitly]
 	public MainWindow() {
 		InitializeComponent();
@@ -20,16 +22,23 @@ public sealed partial class MainWindow : Window {
 		DataContext = new MainWindowModel(this, args);
 	}
 
-	public void OnClosed(object? sender, EventArgs e) {
-		if (DataContext is IDisposable disposable) {
-			disposable.Dispose();
-		}
+	public async void OnClosing(object? sender, WindowClosingEventArgs e) {
+		e.Cancel = true;
+		Closing -= OnClosing;
 
-		foreach (var temporaryFile in ViewerPageModel.TemporaryFiles) {
+		try {
+			await Dispose();
+		} finally {
+			Close();
+		}
+	}
+
+	private async Task Dispose() {
+		if (DataContext is MainWindowModel model) {
 			try {
-				File.Delete(temporaryFile);
-			} catch (Exception) {
-				// ignored
+				await model.DisposeAsync();
+			} catch (Exception ex) {
+				Log.Error("Caught exception while disposing window: " + ex);
 			}
 		}
 	}

app/Desktop/Main/MainWindowModel.cs

@@ -1,33 +1,38 @@
 using System;
-using System.ComponentModel;
 using System.IO;
 using System.Runtime.InteropServices;
 using System.Threading.Tasks;
 using Avalonia.Controls;
+using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Main.Screens;
 using DHT.Desktop.Server;
+using DHT.Server;
 using DHT.Server.Database;
-using DHT.Utils.Models;
+using DHT.Utils.Logging;
 
 namespace DHT.Desktop.Main;
 
-sealed class MainWindowModel : BaseModel, IDisposable {
+sealed partial class MainWindowModel : ObservableObject, IAsyncDisposable {
 	private const string DefaultTitle = "Discord History Tracker";
 
-	public string Title { get; private set; } = DefaultTitle;
+	private static readonly Log Log = Log.ForType<MainWindowModel>();
 
-	public UserControl CurrentScreen { get; private set; }
+	[ObservableProperty(Setter = Access.Private)]
+	private string title = DefaultTitle;
+
+	[ObservableProperty(Setter = Access.Private)]
+	private UserControl currentScreen;
 
 	private readonly WelcomeScreen welcomeScreen;
 	private readonly WelcomeScreenModel welcomeScreenModel;
 
-	private MainContentScreen? mainContentScreen;
 	private MainContentScreenModel? mainContentScreenModel;
 
 	private readonly Window window;
+	private readonly int? concurrentDownloads;
 
-	private IDatabaseFile? db;
+	private State? state;
 
 	[Obsolete("Designer")]
 	public MainWindowModel() : this(null!, Arguments.Empty) {}
@@ -36,10 +41,10 @@ sealed class MainWindowModel : BaseModel, IDisposable {
 		this.window = window;
 
 		welcomeScreenModel = new WelcomeScreenModel(window);
-		welcomeScreen = new WelcomeScreen { DataContext = welcomeScreenModel };
-		CurrentScreen = welcomeScreen;
+		welcomeScreenModel.DatabaseSelected += OnDatabaseSelected;
 
-		welcomeScreenModel.PropertyChanged += WelcomeScreenModelOnPropertyChanged;
+		welcomeScreen = new WelcomeScreen { DataContext = welcomeScreenModel };
+		currentScreen = welcomeScreen;
 
 		var dbFile = args.DatabaseFile;
 		if (!string.IsNullOrWhiteSpace(dbFile)) {
@@ -63,54 +68,63 @@ sealed class MainWindowModel : BaseModel, IDisposable {
 		}
 
 		if (args.ServerPort != null) {
-			ServerManager.Port = args.ServerPort.Value;
+			ServerConfiguration.Port = args.ServerPort.Value;
 		}
 
 		if (args.ServerToken != null) {
-			ServerManager.Token = args.ServerToken;
+			ServerConfiguration.Token = args.ServerToken;
+		}
+		
+		concurrentDownloads = args.ConcurrentDownloads;
+	}
+
+	private async void OnDatabaseSelected(object? sender, IDatabaseFile db) {
+		welcomeScreenModel.DatabaseSelected -= OnDatabaseSelected;
+		
+		await DisposeState();
+		
+		state = new State(db, concurrentDownloads);
+
+		try {
+			await state.Server.Start(ServerConfiguration.Port, ServerConfiguration.Token);
+		} catch (Exception ex) {
+			Log.Error(ex);
+			await Dialog.ShowOk(window, "Internal Server Error", ex.Message);
+		}
+
+		mainContentScreenModel = new MainContentScreenModel(window, state);
+		mainContentScreenModel.DatabaseClosed += MainContentScreenModelOnDatabaseClosed;
+		
+		Title = Path.GetFileName(state.Db.Path) + " - " + DefaultTitle;
+		CurrentScreen = new MainContentScreen { DataContext = mainContentScreenModel };
+
+		window.Focus();
+	}
+
+	private async void MainContentScreenModelOnDatabaseClosed(object? sender, EventArgs e) {
+		if (mainContentScreenModel != null) {
+			mainContentScreenModel.DatabaseClosed -= MainContentScreenModelOnDatabaseClosed;
+			mainContentScreenModel.Dispose();
+			mainContentScreenModel = null;
+		}
+
+		await DisposeState();
+
+		Title = DefaultTitle;
+		CurrentScreen = welcomeScreen;
+
+		welcomeScreenModel.DatabaseSelected += OnDatabaseSelected;
+	}
+
+	private async Task DisposeState() {
+		if (state != null) {
+			await state.DisposeAsync();
+			state = null;
 		}
 	}
 
-	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();
+	public async ValueTask DisposeAsync() {
 		mainContentScreenModel?.Dispose();
-		db?.Dispose();
-		db = null;
+		await DisposeState();
 	}
 }

app/Desktop/Main/Pages/AdvancedPage.axaml

@@ -5,7 +5,8 @@
              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.AdvancedPage">
+             x:Class="DHT.Desktop.Main.Pages.AdvancedPage"
+             x:DataType="pages:AdvancedPageModel">
 
     <Design.DataContext>
         <pages:AdvancedPageModel />

app/Desktop/Main/Pages/AdvancedPageModel.cs

@@ -1,39 +1,36 @@
 using System;
+using System.Threading.Tasks;
 using Avalonia.Controls;
 using DHT.Desktop.Dialogs.Message;
+using DHT.Desktop.Dialogs.Progress;
 using DHT.Desktop.Main.Controls;
-using DHT.Desktop.Server;
-using DHT.Server.Database;
-using DHT.Utils.Models;
+using DHT.Server;
 
 namespace DHT.Desktop.Main.Pages;
 
-sealed class AdvancedPageModel : BaseModel, IDisposable {
+sealed class AdvancedPageModel : IDisposable {
 	public ServerConfigurationPanelModel ServerConfigurationModel { get; }
-
+	
 	private readonly Window window;
-	private readonly IDatabaseFile db;
+	private readonly State state;
 
 	[Obsolete("Designer")]
-	public AdvancedPageModel() : this(null!, DummyDatabaseFile.Instance, new ServerManager(DummyDatabaseFile.Instance)) {}
+	public AdvancedPageModel() : this(null!, State.Dummy) {}
 
-	public AdvancedPageModel(Window window, IDatabaseFile db, ServerManager serverManager) {
+	public AdvancedPageModel(Window window, State state) {
 		this.window = window;
-		this.db = db;
+		this.state = state;
 
-		ServerConfigurationModel = new ServerConfigurationPanelModel(window, serverManager);
-	}
-
-	public void Initialize() {
-		ServerConfigurationModel.Initialize();
+		ServerConfigurationModel = new ServerConfigurationPanelModel(window, state);
 	}
 
 	public void Dispose() {
 		ServerConfigurationModel.Dispose();
 	}
 
-	public async void VacuumDatabase() {
-		db.Vacuum();
-		await Dialog.ShowOk(window, "Vacuum Database", "Done.");
+	public async Task VacuumDatabase() {
+		const string Title = "Vacuum Database";
+		await ProgressDialog.ShowIndeterminate(window, Title, "Vacuuming database...", _ => state.Db.Vacuum());
+		await Dialog.ShowOk(window, Title, "Done.");
 	}
 }

app/Desktop/Main/Pages/AttachmentsPageModel.cs

@@ -1,205 +0,0 @@
-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

@@ -4,7 +4,8 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:pages="clr-namespace:DHT.Desktop.Main.Pages"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="DHT.Desktop.Main.Pages.DatabasePage">
+             x:Class="DHT.Desktop.Main.Pages.DatabasePage"
+             x:DataType="pages:DatabasePageModel">
 
     <Design.DataContext>
         <pages:DatabasePageModel />

app/Desktop/Main/Pages/DatabasePageModel.cs

@@ -14,15 +14,16 @@ using DHT.Desktop.Dialogs.File;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Dialogs.Progress;
 using DHT.Desktop.Dialogs.TextBox;
+using DHT.Server;
 using DHT.Server.Data;
 using DHT.Server.Database;
 using DHT.Server.Database.Import;
+using DHT.Server.Database.Sqlite.Schema;
 using DHT.Utils.Logging;
-using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Pages; 
+namespace DHT.Desktop.Main.Pages;
 
-sealed class DatabasePageModel : BaseModel {
+sealed class DatabasePageModel {
 	private static readonly Log Log = Log.ForType<DatabasePageModel>();
 
 	public IDatabaseFile Db { get; }
@@ -32,14 +33,14 @@ sealed class DatabasePageModel : BaseModel {
 	private readonly Window window;
 
 	[Obsolete("Designer")]
-	public DatabasePageModel() : this(null!, DummyDatabaseFile.Instance) {}
+	public DatabasePageModel() : this(null!, State.Dummy) {}
 
-	public DatabasePageModel(Window window, IDatabaseFile db) {
+	public DatabasePageModel(Window window, State state) {
 		this.window = window;
-		this.Db = db;
+		this.Db = state.Db;
 	}
 
-	public async void OpenDatabaseFolder() {
+	public async Task OpenDatabaseFolder() {
 		string file = Db.Path;
 		string? folder = Path.GetDirectoryName(file);
 
@@ -70,69 +71,77 @@ sealed class DatabasePageModel : BaseModel {
 		DatabaseClosed?.Invoke(this, EventArgs.Empty);
 	}
 
-	public async void MergeWithDatabase() {
+	public async Task MergeWithDatabase() {
 		var paths = await DatabaseGui.NewOpenDatabaseFilesDialog(window, Path.GetDirectoryName(Db.Path));
-		if (paths.Length == 0) {
-			return;
+		if (paths.Length > 0) {
+			await ProgressDialog.Show(window, "Database Merge", async (dialog, callback) => await MergeWithDatabaseFromPaths(Db, paths, dialog, callback));
 		}
-
-		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;
-		}
+		var schemaUpgradeCallbacks = new SchemaUpgradeCallbacks(dialog, paths.Length);
 
 		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);
+			IDatabaseFile? db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, dialog, schemaUpgradeCallbacks);
 
 			if (db == null) {
 				return false;
 			}
 
 			try {
-				target.AddFrom(db);
+				await target.AddFrom(db);
 				return true;
 			} finally {
-				db.Dispose();
+				await db.DisposeAsync();
 			}
 		});
 	}
 
-	public async void ImportLegacyArchive() {
+	private sealed class SchemaUpgradeCallbacks : ISchemaUpgradeCallbacks {
+		private readonly ProgressDialog dialog;
+		private readonly int total;
+		private bool? decision;
+
+		public SchemaUpgradeCallbacks(ProgressDialog dialog, int total) {
+			this.total = total;
+			this.dialog = dialog;
+		}
+
+		public async Task<bool> CanUpgrade() {
+			return decision ??= (total > 1
+				                     ? await DatabaseGui.ShowCanUpgradeMultipleDatabaseDialog(dialog)
+				                     : await DatabaseGui.ShowCanUpgradeDatabaseDialog(dialog)) == DialogResult.YesNo.Yes;
+		}
+
+		public Task Start(int versionSteps, Func<ISchemaUpgradeCallbacks.IProgressReporter, Task> doUpgrade) {
+			return doUpgrade(new NullReporter());
+		}
+
+		private sealed class NullReporter : ISchemaUpgradeCallbacks.IProgressReporter {
+			public Task NextVersion() {
+				return Task.CompletedTask;
+			}
+
+			public Task MainWork(string message, int finishedItems, int totalItems) {
+				return Task.CompletedTask;
+			}
+
+			public Task SubWork(string message, int finishedItems, int totalItems) {
+				return Task.CompletedTask;
+			}
+		}
+	}
+
+	public async Task 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;
+
+		if (paths.Length > 0) {
+			await ProgressDialog.Show(window, "Legacy Archive Import", async (dialog, callback) => await ImportLegacyArchiveFromPaths(Db, paths, dialog, callback));
 		}
-
-		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) {
@@ -140,7 +149,7 @@ sealed class DatabasePageModel : BaseModel {
 
 		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());
@@ -155,7 +164,7 @@ sealed class DatabasePageModel : BaseModel {
 		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)) {
@@ -184,7 +193,7 @@ sealed class DatabasePageModel : BaseModel {
 
 	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();
+		var oldStatistics = await DatabaseStatistics.Take(target);
 
 		int successful = 0;
 		int finished = 0;
@@ -215,14 +224,26 @@ sealed class DatabasePageModel : BaseModel {
 			return;
 		}
 
-		await Dialog.ShowOk(dialog, neutralDialogTitle, GetImportDialogMessage(oldStatistics, target.SnapshotStatistics(), successful, total, itemName));
+		var newStatistics = await DatabaseStatistics.Take(target);
+		await Dialog.ShowOk(dialog, neutralDialogTitle, GetImportDialogMessage(oldStatistics, newStatistics, 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;
+	private sealed record DatabaseStatistics(long ServerCount, long ChannelCount, long UserCount, long MessageCount) {
+		public static async Task<DatabaseStatistics> Take(IDatabaseFile db) {
+			return new DatabaseStatistics(
+				await db.Servers.Count(),
+				await db.Channels.Count(),
+				await db.Users.Count(),
+				await db.Messages.Count()
+			);
+		}
+	}
+
+	private static string GetImportDialogMessage(DatabaseStatistics oldStatistics, DatabaseStatistics newStatistics, int successfulItems, int totalItems, string itemName) {
+		long newServers = newStatistics.ServerCount - oldStatistics.ServerCount;
+		long newChannels = newStatistics.ChannelCount - oldStatistics.ChannelCount;
+		long newUsers = newStatistics.UserCount - oldStatistics.UserCount;
+		long newMessages = newStatistics.MessageCount - oldStatistics.MessageCount;
 
 		StringBuilder message = new StringBuilder();
 		message.Append("Processed ");

app/Desktop/Main/Pages/DebugPage.axaml

@@ -4,7 +4,8 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:pages="clr-namespace:DHT.Desktop.Main.Pages"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="DHT.Desktop.Main.Pages.DebugPage">
+             x:Class="DHT.Desktop.Main.Pages.DebugPage"
+             x:DataType="pages:DebugPageModel">
     
     <Design.DataContext>
         <pages:DebugPageModel />

app/Desktop/Main/Pages/DebugPageModel.cs

@@ -6,180 +6,168 @@ using System.Threading.Tasks;
 using Avalonia.Controls;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Dialogs.Progress;
+using DHT.Server;
 using DHT.Server.Data;
-using DHT.Server.Database;
 using DHT.Server.Service;
-using DHT.Utils.Models;
 
-namespace DHT.Desktop.Main.Pages {
-	sealed class DebugPageModel : BaseModel {
-		public string GenerateChannels { get; set; } = "0";
-		public string GenerateUsers { get; set; } = "0";
-		public string GenerateMessages { get; set; } = "0";
+namespace DHT.Desktop.Main.Pages;
 
-		private readonly Window window;
-		private readonly IDatabaseFile db;
+sealed class DebugPageModel {
+	public string GenerateChannels { get; set; } = "0";
+	public string GenerateUsers { get; set; } = "0";
+	public string GenerateMessages { get; set; } = "0";
 
-		[Obsolete("Designer")]
-		public DebugPageModel() : this(null!, DummyDatabaseFile.Instance) {}
+	private readonly Window window;
+	private readonly State state;
 
-		public DebugPageModel(Window window, IDatabaseFile db) {
-			this.window = window;
-			this.db = db;
+	[Obsolete("Designer")]
+	public DebugPageModel() : this(null!, State.Dummy) {}
+
+	public DebugPageModel(Window window, State state) {
+		this.window = window;
+		this.state = state;
+	}
+
+	public async void OnClickAddRandomDataToDatabase() {
+		if (!int.TryParse(GenerateChannels, out int channels) || channels < 1) {
+			await Dialog.ShowOk(window, "Generate Random Data", "Amount of channels must be at least 1!");
+			return;
 		}
 
-		public async void OnClickAddRandomDataToDatabase() {
-			if (!int.TryParse(GenerateChannels, out int channels) || channels < 1) {
-				await Dialog.ShowOk(window, "Generate Random Data", "Amount of channels must be at least 1!");
-				return;
-			}
-
-			if (!int.TryParse(GenerateUsers, out int users) || users < 1) {
-				await Dialog.ShowOk(window, "Generate Random Data", "Amount of users must be at least 1!");
-				return;
-			}
-
-			if (!int.TryParse(GenerateMessages, out int messages) || messages < 1) {
-				await Dialog.ShowOk(window, "Generate Random Data", "Amount of messages must be at least 1!");
-				return;
-			}
-
-			ProgressDialog progressDialog = new ProgressDialog {
-				DataContext = new ProgressDialogModel(async callback => await GenerateRandomData(channels, users, messages, callback)) {
-					Title = "Generating Random Data"
-				}
-			};
-
-			await progressDialog.ShowDialog(window);
+		if (!int.TryParse(GenerateUsers, out int users) || users < 1) {
+			await Dialog.ShowOk(window, "Generate Random Data", "Amount of users must be at least 1!");
+			return;
 		}
 
-		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);
-
-			var rand = new Random();
-			var server = new DHT.Server.Data.Server {
-				Id = RandomId(rand),
-				Name = RandomName("s"),
-				Type = ServerType.Server,
-			};
-
-			var channels = Enumerable.Range(0, channelCount).Select(i => new Channel {
-				Id = RandomId(rand),
-				Server = server.Id,
-				Name = RandomName("c"),
-				ParentId = null,
-				Position = i,
-				Topic = RandomText(rand, 10),
-				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(),
-			}).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? 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,
-						Channel = RandomBiasedIndex(rand, channels).Id,
-						Text = RandomText(rand, 100),
-						Timestamp = timeMillis,
-						EditTimestamp = editMillis,
-						RepliedToId = null,
-						Attachments = ImmutableArray<Attachment>.Empty,
-						Embeds = ImmutableArray<Embed>.Empty,
-						Reactions = ImmutableArray<Reaction>.Empty,
-					};
-				}).ToArray();
-
-				db.AddMessages(messages);
-
-				messageCount -= BatchSize;
-				await callback.Update("Adding messages in batches of " + BatchSize, ++batchIndex, batchCount);
-			}
+		if (!int.TryParse(GenerateMessages, out int messages) || messages < 1) {
+			await Dialog.ShowOk(window, "Generate Random Data", "Amount of messages must be at least 1!");
+			return;
 		}
 
-		private static ulong RandomId(Random rand) {
-			ulong h = unchecked((ulong) rand.Next());
-			ulong l = unchecked((ulong) rand.Next());
-			return (h << 32) | l;
-		}
+		await ProgressDialog.Show(window, "Generating Random Data", async (_, callback) => await GenerateRandomData(channels, users, messages, callback));
+	}
 
-		private static string RandomName(string prefix) {
-			return prefix + "-" + ServerUtils.GenerateRandomToken(5);
-		}
+	private const int BatchSize = 500;
 
-		private static T RandomBiasedIndex<T>(Random rand, T[] options) {
-			return options[(int) Math.Floor(options.Length * rand.NextDouble() * rand.NextDouble())];
-		}
+	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);
 
-		private static readonly string[] RandomWords = {
-			"apple", "apricot", "artichoke", "arugula", "asparagus", "avocado",
-			"banana", "bean", "beechnut", "beet", "blackberry", "blackcurrant", "blueberry", "boysenberry", "bramble", "broccoli",
-			"cabbage", "cacao", "cantaloupe", "caper", "carambola", "carrot", "cauliflower", "celery", "chard", "cherry", "chokeberry", "citron", "clementine", "coconut", "corn", "crabapple", "cranberry", "cucumber", "currant",
-			"daikon", "date", "dewberry", "durian",
-			"edamame", "eggplant", "elderberry", "endive",
-			"fig",
-			"garlic", "ginger", "gooseberry", "grape", "grapefruit", "guava",
-			"honeysuckle", "horseradish", "huckleberry",
-			"jackfruit", "jicama",
-			"kale", "kiwi", "kohlrabi", "kumquat",
-			"leek", "lemon", "lentil", "lettuce", "lime",
-			"mandarin", "mango", "mushroom", "myrtle",
-			"nectarine", "nut",
-			"olive", "okra", "onion", "orange",
-			"papaya", "parsnip", "pawpaw", "peach", "pear", "pea", "pepper", "persimmon", "pineapple", "plum", "plantain", "pomegranate", "pomelo", "potato", "prune", "pumpkin",
-			"quandong", "quinoa",
-			"radicchio", "radish", "raisin", "raspberry", "redcurrant", "rhubarb", "rutabaga",
-			"spinach", "strawberry", "squash",
-			"tamarind", "tangerine", "tomatillo", "tomato", "turnip",
-			"vanilla",
-			"watercress", "watermelon",
-			"yam",
-			"zucchini",
+		var rand = new Random();
+		var server = new DHT.Server.Data.Server {
+			Id = RandomId(rand),
+			Name = RandomName("s"),
+			Type = ServerType.Server,
 		};
 
-		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)]));
+		var channels = Enumerable.Range(0, channelCount).Select(i => new Channel {
+			Id = RandomId(rand),
+			Server = server.Id,
+			Name = RandomName("c"),
+			ParentId = null,
+			Position = i,
+			Topic = RandomText(rand, 10),
+			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(),
+		}).ToArray();
+
+		await state.Db.Users.Add(users);
+		await state.Db.Servers.Add([server]);
+		await state.Db.Channels.Add(channels);
+
+		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? 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,
+					Channel = RandomBiasedIndex(rand, channels).Id,
+					Text = RandomText(rand, 100),
+					Timestamp = timeMillis,
+					EditTimestamp = editMillis,
+					RepliedToId = null,
+					Attachments = ImmutableList<Attachment>.Empty,
+					Embeds = ImmutableList<Embed>.Empty,
+					Reactions = ImmutableList<Reaction>.Empty,
+				};
+			}).ToArray();
+
+			await state.Db.Messages.Add(messages);
+
+			messageCount -= BatchSize;
+			await callback.Update("Adding messages in batches of " + BatchSize, ++batchIndex, batchCount);
 		}
 	}
+
+	private static ulong RandomId(Random rand) {
+		ulong h = unchecked((ulong) rand.Next());
+		ulong l = unchecked((ulong) rand.Next());
+		return (h << 32) | l;
+	}
+
+	private static string RandomName(string prefix) {
+		return prefix + "-" + ServerUtils.GenerateRandomToken(5);
+	}
+
+	private static T RandomBiasedIndex<T>(Random rand, T[] options) {
+		return options[(int) Math.Floor(options.Length * rand.NextDouble() * rand.NextDouble())];
+	}
+
+	private static readonly string[] RandomWords = [
+		"apple", "apricot", "artichoke", "arugula", "asparagus", "avocado",
+		"banana", "bean", "beechnut", "beet", "blackberry", "blackcurrant", "blueberry", "boysenberry", "bramble", "broccoli",
+		"cabbage", "cacao", "cantaloupe", "caper", "carambola", "carrot", "cauliflower", "celery", "chard", "cherry", "chokeberry", "citron", "clementine", "coconut", "corn", "crabapple", "cranberry", "cucumber", "currant",
+		"daikon", "date", "dewberry", "durian",
+		"edamame", "eggplant", "elderberry", "endive",
+		"fig",
+		"garlic", "ginger", "gooseberry", "grape", "grapefruit", "guava",
+		"honeysuckle", "horseradish", "huckleberry",
+		"jackfruit", "jicama",
+		"kale", "kiwi", "kohlrabi", "kumquat",
+		"leek", "lemon", "lentil", "lettuce", "lime",
+		"mandarin", "mango", "mushroom", "myrtle",
+		"nectarine", "nut",
+		"olive", "okra", "onion", "orange",
+		"papaya", "parsnip", "pawpaw", "peach", "pear", "pea", "pepper", "persimmon", "pineapple", "plum", "plantain", "pomegranate", "pomelo", "potato", "prune", "pumpkin",
+		"quandong", "quinoa",
+		"radicchio", "radish", "raisin", "raspberry", "redcurrant", "rhubarb", "rutabaga",
+		"spinach", "strawberry", "squash",
+		"tamarind", "tangerine", "tomatillo", "tomato", "turnip",
+		"vanilla",
+		"watercress", "watermelon",
+		"yam",
+		"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)]));
+	}
 }
 #else
-using DHT.Utils.Models;
+namespace DHT.Desktop.Main.Pages;
 
-namespace DHT.Desktop.Main.Pages {
-	sealed class DebugPageModel : BaseModel {
-		public string GenerateChannels { get; set; } = "0";
-		public string GenerateUsers { get; set; } = "0";
-		public string GenerateMessages { get; set; } = "0";
+sealed class DebugPageModel {
+	public string GenerateChannels { get; set; } = "0";
+	public string GenerateUsers { get; set; } = "0";
+	public string GenerateMessages { get; set; } = "0";
 
-		public void OnClickAddRandomDataToDatabase() {}
-	}
+	public void OnClickAddRandomDataToDatabase() {}
 }
 #endif

app/Desktop/Main/Pages/DownloadsPage.axaml

@@ -5,10 +5,11 @@
              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">
+             x:Class="DHT.Desktop.Main.Pages.DownloadsPage"
+             x:DataType="pages:DownloadsPageModel">
 
     <Design.DataContext>
-        <pages:AttachmentsPageModel />
+        <pages:DownloadsPageModel />
     </Design.DataContext>
 
     <UserControl.Styles>
@@ -30,24 +31,20 @@
     </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}}" />
+        <Button Command="{Binding OnClickToggleDownload}" Content="{Binding ToggleDownloadButtonText}" IsEnabled="{Binding IsToggleDownloadButtonEnabled}" />
+        <controls:DownloadItemFilterPanel DataContext="{Binding FilterModel}" IsEnabled="{Binding !$parent[UserControl].((pages:DownloadsPageModel)DataContext).IsDownloading}" />
         <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" />
+                        <DataGridTextColumn Header="State" Binding="{Binding State, Mode=OneWay}" Width="*" />
+                        <DataGridTextColumn Header="Files" Binding="{Binding Items, Mode=OneWay, Converter={StaticResource NumberValueConverter}}" Width="*" CellStyleClasses="right" />
+                        <DataGridTextColumn Header="Size" Binding="{Binding SizeText, Mode=OneWay}" Width="*" CellStyleClasses="right" />
                     </DataGrid.Columns>
                 </DataGrid>
             </Expander>
             <StackPanel Orientation="Horizontal" Spacing="10">
-                <Button Command="{Binding OnClickRetryFailedDownloads}" IsEnabled="{Binding HasFailedDownloads}">Retry Failed Downloads</Button>
+                <Button Command="{Binding OnClickRetryFailedDownloads}" IsEnabled="{Binding IsRetryFailedOnDownloadsButtonEnabled}">Retry Failed Downloads</Button>
             </StackPanel>
         </StackPanel>
     </StackPanel>

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

@@ -4,8 +4,8 @@ using Avalonia.Controls;
 namespace DHT.Desktop.Main.Pages;
 
 [SuppressMessage("ReSharper", "MemberCanBeInternal")]
-public sealed partial class AttachmentsPage : UserControl {
-	public AttachmentsPage() {
+public sealed partial class DownloadsPage : UserControl {
+	public DownloadsPage() {
 		InitializeComponent();
 	}
 }

app/Desktop/Main/Pages/DownloadsPageModel.cs

@@ -0,0 +1,186 @@
+using System;
+using System.Collections.ObjectModel;
+using System.Reactive.Linq;
+using System.Threading.Tasks;
+using Avalonia.ReactiveUI;
+using CommunityToolkit.Mvvm.ComponentModel;
+using DHT.Desktop.Common;
+using DHT.Desktop.Main.Controls;
+using DHT.Server;
+using DHT.Server.Data.Aggregations;
+using DHT.Server.Data.Filters;
+using DHT.Server.Download;
+using DHT.Utils.Logging;
+using DHT.Utils.Tasks;
+
+namespace DHT.Desktop.Main.Pages;
+
+sealed partial class DownloadsPageModel : ObservableObject, IDisposable {
+	private static readonly Log Log = Log.ForType<DownloadsPageModel>();
+
+	[ObservableProperty(Setter = Access.Private)]
+	private bool isToggleDownloadButtonEnabled = true;
+
+	public string ToggleDownloadButtonText => IsDownloading ? "Stop Downloading" : "Start Downloading";
+
+	[ObservableProperty(Setter = Access.Private)]
+	[NotifyPropertyChangedFor(nameof(IsRetryFailedOnDownloadsButtonEnabled))]
+	private bool isRetryingFailedDownloads = false;
+
+	[ObservableProperty(Setter = Access.Private)]
+	[NotifyPropertyChangedFor(nameof(IsRetryFailedOnDownloadsButtonEnabled))]
+	private bool hasFailedDownloads;
+
+	public bool IsRetryFailedOnDownloadsButtonEnabled => !IsRetryingFailedDownloads && HasFailedDownloads;
+
+	[ObservableProperty(Setter = Access.Private)]
+	private string downloadMessage = "";
+
+	public DownloadItemFilterPanelModel FilterModel { get; }
+
+	private readonly StatisticsRow statisticsPending = new ("Pending");
+	private readonly StatisticsRow statisticsDownloaded = new ("Downloaded");
+	private readonly StatisticsRow statisticsFailed = new ("Failed");
+	private readonly StatisticsRow statisticsSkipped = new ("Skipped");
+
+	public ObservableCollection<StatisticsRow> StatisticsRows { get; }
+
+	public bool IsDownloading => state.Downloader.IsDownloading;
+
+	private readonly State state;
+	private readonly ThrottledTask<DownloadStatusStatistics> downloadStatisticsTask;
+	private readonly IDisposable downloadItemCountSubscription;
+	
+	private IDisposable? finishedItemsSubscription;
+	private DownloadItemFilter? currentDownloadFilter;
+
+	public DownloadsPageModel() : this(State.Dummy) {}
+
+	public DownloadsPageModel(State state) {
+		this.state = state;
+
+		FilterModel = new DownloadItemFilterPanelModel(state);
+		
+		StatisticsRows = [
+			statisticsPending,
+			statisticsDownloaded,
+			statisticsFailed,
+			statisticsSkipped
+		];
+
+		downloadStatisticsTask = new ThrottledTask<DownloadStatusStatistics>(Log, UpdateStatistics, TaskScheduler.FromCurrentSynchronizationContext());
+		downloadItemCountSubscription = state.Db.Downloads.TotalCount.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnDownloadCountChanged);
+
+		RecomputeDownloadStatistics();
+	}
+
+	public void Dispose() {
+		finishedItemsSubscription?.Dispose();
+		
+		downloadItemCountSubscription.Dispose();
+		downloadStatisticsTask.Dispose();
+
+		FilterModel.Dispose();
+	}
+
+	private void OnDownloadCountChanged(long newDownloadCount) {
+		RecomputeDownloadStatistics();
+	}
+
+	public async Task OnClickToggleDownload() {
+		IsToggleDownloadButtonEnabled = false;
+
+		if (IsDownloading) {
+			await state.Downloader.Stop();
+			await state.Db.Downloads.MoveDownloadingItemsBackToQueue();
+
+			finishedItemsSubscription?.Dispose();
+			finishedItemsSubscription = null;
+			
+			currentDownloadFilter = null;
+		}
+		else {
+			await state.Db.Downloads.MoveDownloadingItemsBackToQueue();
+			
+			var finishedItems = await state.Downloader.Start(currentDownloadFilter = FilterModel.CreateFilter());
+			finishedItemsSubscription = finishedItems.ObserveOn(AvaloniaScheduler.Instance).Subscribe(OnItemFinished);
+		}
+
+		RecomputeDownloadStatistics();
+
+		OnPropertyChanged(nameof(ToggleDownloadButtonText));
+		OnPropertyChanged(nameof(IsDownloading));
+		IsToggleDownloadButtonEnabled = true;
+	}
+
+	private void OnItemFinished(DownloadItem item) {
+		RecomputeDownloadStatistics();
+	}
+
+	public async Task OnClickRetryFailedDownloads() {
+		IsRetryingFailedDownloads = true;
+
+		try {
+			await state.Db.Downloads.RetryFailed();
+			RecomputeDownloadStatistics();
+		} catch (Exception e) {
+			Log.Error(e);
+		} finally {
+			IsRetryingFailedDownloads = false;
+		}
+	}
+
+	private void RecomputeDownloadStatistics() {
+		downloadStatisticsTask.Post(cancellationToken => state.Db.Downloads.GetStatistics(currentDownloadFilter ?? new DownloadItemFilter(), cancellationToken));
+	}
+
+	private void UpdateStatistics(DownloadStatusStatistics statusStatistics) {
+		statisticsPending.Items = statusStatistics.PendingCount;
+		statisticsPending.Size = statusStatistics.PendingTotalSize;
+		statisticsPending.HasFilesWithUnknownSize = statusStatistics.PendingWithUnknownSizeCount > 0;
+
+		statisticsDownloaded.Items = statusStatistics.SuccessfulCount;
+		statisticsDownloaded.Size = statusStatistics.SuccessfulTotalSize;
+		statisticsDownloaded.HasFilesWithUnknownSize = statusStatistics.SuccessfulWithUnknownSizeCount > 0;
+
+		statisticsFailed.Items = statusStatistics.FailedCount;
+		statisticsFailed.Size = statusStatistics.FailedTotalSize;
+		statisticsFailed.HasFilesWithUnknownSize = statusStatistics.FailedWithUnknownSizeCount > 0;
+		
+		statisticsSkipped.Items = statusStatistics.SkippedCount;
+		statisticsSkipped.Size = statusStatistics.SkippedTotalSize;
+		statisticsSkipped.HasFilesWithUnknownSize = statusStatistics.SkippedWithUnknownSizeCount > 0;
+
+		HasFailedDownloads = statusStatistics.FailedCount > 0;
+	}
+
+	[ObservableObject]
+	public sealed partial class StatisticsRow(string state) {
+		public string State { get; } = state;
+
+		[ObservableProperty]
+		private int items;
+
+		[ObservableProperty]
+		[NotifyPropertyChangedFor(nameof(SizeText))]
+		private ulong? size;
+		
+		[ObservableProperty]
+		[NotifyPropertyChangedFor(nameof(SizeText))]
+		private bool hasFilesWithUnknownSize;
+
+		public string SizeText {
+			get {
+				if (size == null) {
+					return "-";
+				}
+				else if (hasFilesWithUnknownSize) {
+					return "\u2265 " + BytesValueConverter.Convert(size.Value);
+				}
+				else {
+					return BytesValueConverter.Convert(size.Value);
+				}
+			}
+		}
+	}
+}

app/Desktop/Main/Pages/TrackingPage.axaml

@@ -4,7 +4,8 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:pages="clr-namespace:DHT.Desktop.Main.Pages"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="DHT.Desktop.Main.Pages.TrackingPage">
+             x:Class="DHT.Desktop.Main.Pages.TrackingPage"
+             x:DataType="pages:TrackingPageModel">
 
     <Design.DataContext>
         <pages:TrackingPageModel />
@@ -15,7 +16,7 @@
             To start tracking messages, copy the tracking script and paste it into the console of either the Discord app, or your browser. The console is usually opened by pressing Ctrl+Shift+I.
         </TextBlock>
         <StackPanel DockPanel.Dock="Left" Orientation="Horizontal" Spacing="10">
-            <Button x:Name="CopyTrackingScript" Click="CopyTrackingScriptButton_OnClick">Copy Tracking Script</Button>
+            <Button x:Name="CopyTrackingScript" Click="CopyTrackingScriptButton_OnClick" IsEnabled="{Binding IsCopyTrackingScriptButtonEnabled}">Copy Tracking Script</Button>
         </StackPanel>
         <TextBlock TextWrapping="Wrap" Margin="0 5 0 0">
             By default, the Discord app does not allow opening the console. The button below will change a hidden setting in the Discord app that controls whether the Ctrl+Shift+I shortcut is enabled.

app/Desktop/Main/Pages/TrackingPageModel.cs

@@ -1,35 +1,39 @@
 using System;
+using System.Threading;
 using System.Threading.Tasks;
 using System.Web;
 using Avalonia.Controls;
+using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Discord;
 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;
+sealed partial class TrackingPageModel : ObservableObject {
+	[ObservableProperty(Setter = Access.Private)]
+	private bool isCopyTrackingScriptButtonEnabled = true;
 
-	private bool AreDevToolsEnabled {
-		get => areDevToolsEnabled;
-		set {
-			Change(ref areDevToolsEnabled, value);
-			OnPropertyChanged(nameof(ToggleAppDevToolsButtonText));
-		}
-	}
+	[ObservableProperty(Setter = Access.Private)]
+	[NotifyPropertyChangedFor(nameof(ToggleAppDevToolsButtonText))]
+	private bool? areDevToolsEnabled = null;
 
-	public bool IsToggleAppDevToolsButtonEnabled { get; private set; } = true;
+	[ObservableProperty(Setter = Access.Private)]
+	[NotifyPropertyChangedFor(nameof(ToggleAppDevToolsButtonText))]
+	private bool isToggleAppDevToolsButtonEnabled = false;
 
 	public string ToggleAppDevToolsButtonText {
 		get {
+			if (!AreDevToolsEnabled.HasValue) {
+				return "Loading...";
+			}
+
 			if (!IsToggleAppDevToolsButtonEnabled) {
 				return "Unavailable";
 			}
 
-			return AreDevToolsEnabled ? "Disable Ctrl+Shift+I" : "Enable Ctrl+Shift+I";
+			return AreDevToolsEnabled.Value ? "Disable Ctrl+Shift+I" : "Enable Ctrl+Shift+I";
 		}
 	}
 
@@ -40,21 +44,22 @@ sealed class TrackingPageModel : BaseModel {
 
 	public TrackingPageModel(Window window) {
 		this.window = window;
+
+		Task.Factory.StartNew(InitializeDevToolsToggle, CancellationToken.None, TaskCreationOptions.None, TaskScheduler.FromCurrentSynchronizationContext());
 	}
 
-	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() {
+		IsCopyTrackingScriptButtonEnabled = false;
+
+		try {
+			return await CopyTrackingScript();
+		} finally {
+			IsCopyTrackingScriptButtonEnabled = true;
 		}
 	}
-	
-	public async Task<bool> OnClickCopyTrackingScript() {
-		string url = $"http://127.0.0.1:{ServerManager.Port}/get-tracking-script?token={HttpUtility.UrlEncode(ServerManager.Token)}";
+
+	private async Task<bool> CopyTrackingScript() {
+		string url = $"http://127.0.0.1:{ServerConfiguration.Port}/get-tracking-script?token={HttpUtility.UrlEncode(ServerConfiguration.Token)}";
 		string script = (await Resources.ReadTextAsync("tracker-loader.js")).Trim().Replace("{url}", url);
 
 		var clipboard = window.Clipboard;
@@ -72,10 +77,26 @@ sealed class TrackingPageModel : BaseModel {
 		}
 	}
 
-	public async void OnClickToggleAppDevTools() {
+	private async Task InitializeDevToolsToggle() {
+		bool? devToolsEnabled = await Task.Run(DiscordAppSettings.AreDevToolsEnabled);
+
+		if (devToolsEnabled.HasValue) {
+			AreDevToolsEnabled = devToolsEnabled.Value;
+			IsToggleAppDevToolsButtonEnabled = true;
+		}
+		else {
+			IsToggleAppDevToolsButtonEnabled = false;
+		}
+	}
+
+	public async Task OnClickToggleAppDevTools() {
 		const string DialogTitle = "Discord App Settings File";
 
-		bool oldState = AreDevToolsEnabled;
+		if (!AreDevToolsEnabled.HasValue) {
+			return;
+		}
+
+		bool oldState = AreDevToolsEnabled.Value;
 		bool newState = !oldState;
 
 		switch (await DiscordAppSettings.ConfigureDevTools(newState)) {

app/Desktop/Main/Pages/ViewerPage.axaml

@@ -5,7 +5,8 @@
              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">
+             x:Class="DHT.Desktop.Main.Pages.ViewerPage"
+             x:DataType="pages:ViewerPageModel">
 
     <Design.DataContext>
         <pages:ViewerPageModel />
@@ -20,7 +21,6 @@
     <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>
         <controls:MessageFilterPanel DataContext="{Binding FilterModel}" />
         <Expander Header="Database Tools">

app/Desktop/Main/Pages/ViewerPageModel.cs

@@ -1,53 +1,41 @@
 using System;
-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 CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
-using DHT.Desktop.Dialogs.File;
 using DHT.Desktop.Dialogs.Message;
+using DHT.Desktop.Dialogs.Progress;
 using DHT.Desktop.Main.Controls;
 using DHT.Desktop.Server;
+using DHT.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;
+using DHT.Server.Service.Viewer;
 
 namespace DHT.Desktop.Main.Pages;
 
-sealed class ViewerPageModel : BaseModel, IDisposable {
-	public static readonly ConcurrentBag<string> TemporaryFiles = new ();
-
+sealed partial class ViewerPageModel : ObservableObject, IDisposable {
 	public bool DatabaseToolFilterModeKeep { get; set; } = true;
 	public bool DatabaseToolFilterModeRemove { get; set; } = false;
 
+	[ObservableProperty]
 	private bool hasFilters = false;
 
-	public bool HasFilters {
-		get => hasFilters;
-		set => Change(ref hasFilters, value);
-	}
-
-	private MessageFilterPanelModel FilterModel { get; }
+	public MessageFilterPanelModel FilterModel { get; }
 
 	private readonly Window window;
-	private readonly IDatabaseFile db;
+	private readonly State state;
 
 	[Obsolete("Designer")]
-	public ViewerPageModel() : this(null!, DummyDatabaseFile.Instance) {}
+	public ViewerPageModel() : this(null!, State.Dummy) {}
 
-	public ViewerPageModel(Window window, IDatabaseFile db) {
+	public ViewerPageModel(Window window, State state) {
 		this.window = window;
-		this.db = db;
+		this.state = state;
 
-		FilterModel = new MessageFilterPanelModel(window, db, "Will export");
+		FilterModel = new MessageFilterPanelModel(window, state, "Will export");
 		FilterModel.FilterPropertyChanged += OnFilterPropertyChanged;
 	}
 
@@ -59,91 +47,37 @@ sealed class ViewerPageModel : BaseModel, IDisposable {
 		HasFilters = FilterModel.HasAnyFilters;
 	}
 
-	private async Task WriteViewerFile(string path, IViewerExportStrategy strategy) {
-		const string ArchiveTag = "/*[ARCHIVE]*/";
-
-		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'));
-
-		int viewerArchiveTagStart = viewerTemplate.IndexOf(ArchiveTag);
-		int viewerArchiveTagEnd = viewerArchiveTagStart + ArchiveTag.Length;
-
-		string jsonTempFile = path + ".tmp";
-
-		await using (var jsonStream = new FileStream(jsonTempFile, FileMode.Create, FileAccess.ReadWrite, FileShare.Read)) {
-			await ViewerJsonExport.Generate(jsonStream, strategy, db, FilterModel.CreateFilter());
-
-			char[] jsonBuffer = new char[Math.Min(32768, jsonStream.Position)];
-			jsonStream.Position = 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]);
-
-				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));
-					}
-				}
-
-				await outputWriter.WriteAsync(viewerTemplate[viewerArchiveTagEnd..]);
-			}
-		}
-
-		File.Delete(jsonTempFile);
-	}
-
 	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);
+		try {
+			string serverUrl = "http://127.0.0.1:" + ServerConfiguration.Port;
+			string serverToken = ServerConfiguration.Token;
+			string sessionId = state.ViewerSessions.Register(new ViewerSession(FilterModel.CreateFilter())).ToString();
+			
+			Process.Start(new ProcessStartInfo(serverUrl + "/viewer/?token=" + HttpUtility.UrlEncode(serverToken) + "&session=" + HttpUtility.UrlEncode(sessionId)) {
+				UseShellExecute = true
+			});
+		} catch (Exception e) {
+			await Dialog.ShowOk(window, "Open Viewer", "Could not open viewer: " + e.Message);
 		}
 	}
 
-	public async void OnClickApplyFiltersToDatabase() {
+	public async Task OnClickApplyFiltersToDatabase() {
 		var filter = FilterModel.CreateFilter();
+		var messageCount = await ProgressDialog.ShowIndeterminate(window, "Apply Filters", "Counting matching messages...", _ => state.Db.Messages.Count(filter));
 
 		if (DatabaseToolFilterModeKeep) {
-			if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Keep Matching Messages in This Database", 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);
+			if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Keep Matching Messages in This Database", messageCount.Pluralize("message") + " will be kept, and the rest will be removed from this database. This action cannot be undone. Proceed?")) {
+				await ApplyFilterToDatabase(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, FilterRemovalMode.RemoveMatching);
+			if (DialogResult.YesNo.Yes == await Dialog.ShowYesNo(window, "Remove Matching Messages in This Database", messageCount.Pluralize("message") + " will be removed from this database. This action cannot be undone. Proceed?")) {
+				await ApplyFilterToDatabase(filter, FilterRemovalMode.RemoveMatching);
 			}
 		}
 	}
+
+	private async Task ApplyFilterToDatabase(MessageFilter filter, FilterRemovalMode removalMode) {
+		await ProgressDialog.ShowIndeterminate(window, "Apply Filters", "Removing messages...", _ => state.Db.Messages.Remove(filter, removalMode));
+	}
 }

app/Desktop/Main/Screens/MainContentScreen.axaml

@@ -5,7 +5,8 @@
              xmlns:controls="clr-namespace:DHT.Desktop.Main.Controls"
              xmlns:screens="clr-namespace:DHT.Desktop.Main.Screens"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="DHT.Desktop.Main.Screens.MainContentScreen">
+             x:Class="DHT.Desktop.Main.Screens.MainContentScreen"
+             x:DataType="screens:MainContentScreenModel">
 
     <Design.DataContext>
         <screens:MainContentScreenModel />
@@ -73,7 +74,7 @@
     <DockPanel>
         <Border Classes="statusBar" DockPanel.Dock="Bottom">
             <DockPanel>
-                <TextBlock Classes="invisibleTabItem" DockPanel.Dock="Left">Attachments</TextBlock>
+                <TextBlock Classes="invisibleTabItem" DockPanel.Dock="Left">Downloads</TextBlock>
                 <controls:StatusBar DataContext="{Binding StatusBarModel}" DockPanel.Dock="Right" />
             </DockPanel>
         </Border>
@@ -93,9 +94,9 @@
                     <ContentPresenter Content="{Binding TrackingPage}" Classes="page" />
                 </ScrollViewer>
             </TabItem>
-            <TabItem x:Name="TabAttachments" Header="Attachments" Grid.Row="2">
+            <TabItem x:Name="TabDownloads" Header="Downloads" Grid.Row="2">
                 <ScrollViewer>
-                    <ContentPresenter Content="{Binding AttachmentsPage}" Classes="page" />
+                    <ContentPresenter Content="{Binding DownloadsPage}" Classes="page" />
                 </ScrollViewer>
             </TabItem>
             <TabItem x:Name="TabViewer" Header="Viewer" Grid.Row="3">

app/Desktop/Main/Screens/MainContentScreenModel.cs

@@ -1,27 +1,20 @@
 using System;
-using System.Threading.Tasks;
 using Avalonia.Controls;
-using DHT.Desktop.Dialogs.Message;
 using DHT.Desktop.Main.Controls;
 using DHT.Desktop.Main.Pages;
-using DHT.Desktop.Server;
-using DHT.Server.Database;
-using DHT.Server.Service;
-using DHT.Utils.Logging;
+using DHT.Server;
 
 namespace DHT.Desktop.Main.Screens;
 
 sealed class MainContentScreenModel : IDisposable {
-	private static readonly Log Log = Log.ForType<MainContentScreenModel>();
-
 	public DatabasePage DatabasePage { get; }
 	private DatabasePageModel DatabasePageModel { get; }
 
 	public TrackingPage TrackingPage { get; }
 	private TrackingPageModel TrackingPageModel { get; }
 
-	public AttachmentsPage AttachmentsPage { get; }
-	private AttachmentsPageModel AttachmentsPageModel { get; }
+	public DownloadsPage DownloadsPage { get; }
+	private DownloadsPageModel DownloadsPageModel { get; }
 
 	public ViewerPage ViewerPage { get; }
 	private ViewerPageModel ViewerPageModel { get; }
@@ -35,7 +28,7 @@ sealed class MainContentScreenModel : IDisposable {
 	public bool HasDebugPage => true;
 	private DebugPageModel DebugPageModel { get; }
 	#else
-		public bool HasDebugPage => false;
+	public bool HasDebugPage => false;
 	#endif
 
 	public StatusBarModel StatusBarModel { get; }
@@ -49,71 +42,39 @@ sealed class MainContentScreenModel : IDisposable {
 		}
 	}
 
-	private readonly Window window;
-	private readonly ServerManager serverManager;
-
 	[Obsolete("Designer")]
-	public MainContentScreenModel() : this(null!, DummyDatabaseFile.Instance) {}
+	public MainContentScreenModel() : this(null!, State.Dummy) {}
 
-	public MainContentScreenModel(Window window, IDatabaseFile db) {
-		this.window = window;
-		this.serverManager = new ServerManager(db);
-
-		ServerLauncher.ServerManagementExceptionCaught += ServerLauncherOnServerManagementExceptionCaught;
-
-		DatabasePageModel = new DatabasePageModel(window, db);
+	public MainContentScreenModel(Window window, State state) {
+		DatabasePageModel = new DatabasePageModel(window, state);
 		DatabasePage = new DatabasePage { DataContext = DatabasePageModel };
 
 		TrackingPageModel = new TrackingPageModel(window);
 		TrackingPage = new TrackingPage { DataContext = TrackingPageModel };
 
-		AttachmentsPageModel = new AttachmentsPageModel(db);
-		AttachmentsPage = new AttachmentsPage { DataContext = AttachmentsPageModel };
+		DownloadsPageModel = new DownloadsPageModel(state);
+		DownloadsPage = new DownloadsPage { DataContext = DownloadsPageModel };
 
-		ViewerPageModel = new ViewerPageModel(window, db);
+		ViewerPageModel = new ViewerPageModel(window, state);
 		ViewerPage = new ViewerPage { DataContext = ViewerPageModel };
 
-		AdvancedPageModel = new AdvancedPageModel(window, db, serverManager);
+		AdvancedPageModel = new AdvancedPageModel(window, state);
 		AdvancedPage = new AdvancedPage { DataContext = AdvancedPageModel };
 
 		#if DEBUG
-		DebugPageModel = new DebugPageModel(window, db);
+		DebugPageModel = new DebugPageModel(window, state);
 		DebugPage = new DebugPage { DataContext = DebugPageModel };
 		#else
-			DebugPage = null;
+		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();
+		StatusBarModel = new StatusBarModel(state);
 	}
 
 	public void Dispose() {
-		ServerLauncher.ServerManagementExceptionCaught -= ServerLauncherOnServerManagementExceptionCaught;
-		AttachmentsPageModel.Dispose();
+		DownloadsPageModel.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);
+		AdvancedPageModel.Dispose();
+		StatusBarModel.Dispose();
 	}
 }

app/Desktop/Main/Screens/WelcomeScreen.axaml

@@ -4,7 +4,8 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:screens="clr-namespace:DHT.Desktop.Main.Screens"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="DHT.Desktop.Main.Screens.WelcomeScreen">
+             x:Class="DHT.Desktop.Main.Screens.WelcomeScreen"
+             x:DataType="screens:WelcomeScreenModel">
 
     <Design.DataContext>
         <screens:WelcomeScreenModel />
@@ -31,7 +32,7 @@
             <TextBlock Text="{Binding Version, StringFormat=Discord History Tracker v{0}}" FontSize="25" Margin="0 0 0 30" HorizontalAlignment="Center" />
 
             <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
-                <Button Command="{Binding OpenOrCreateDatabase}">Open or Create Database</Button>
+                <Button Command="{Binding OpenOrCreateDatabase}" IsEnabled="{Binding IsOpenOrCreateDatabaseButtonEnabled}">Open or Create Database</Button>
                 <Button Command="{Binding ShowAboutDialog}">About</Button>
                 <Button Command="{Binding Exit}">Exit</Button>
             </StackPanel>

app/Desktop/Main/Screens/WelcomeScreenModel.cs

@@ -1,20 +1,25 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Threading.Tasks;
 using Avalonia.Controls;
+using CommunityToolkit.Mvvm.ComponentModel;
 using DHT.Desktop.Common;
 using DHT.Desktop.Dialogs.Message;
+using DHT.Desktop.Dialogs.Progress;
 using DHT.Server.Database;
-using DHT.Utils.Models;
+using DHT.Server.Database.Sqlite.Schema;
 
 namespace DHT.Desktop.Main.Screens;
 
-sealed class WelcomeScreenModel : BaseModel, IDisposable {
+sealed partial class WelcomeScreenModel : ObservableObject {
 	public string Version => Program.Version;
-
-	public IDatabaseFile? Db { get; private set; }
-	public bool HasDatabase => Db != null;
-
+	
+	[ObservableProperty(Setter = Access.Private)]
+	private bool isOpenOrCreateDatabaseButtonEnabled = true;
+	
+	public event EventHandler<IDatabaseFile>? DatabaseSelected; 
+	
 	private readonly Window window;
 
 	private string? dbFilePath;
@@ -26,45 +31,89 @@ sealed class WelcomeScreenModel : BaseModel, IDisposable {
 		this.window = window;
 	}
 
-	public async void OpenOrCreateDatabase() {
-		var path = await DatabaseGui.NewOpenOrCreateDatabaseFileDialog(window, Path.GetDirectoryName(dbFilePath));
-		if (path != null) {
-			await OpenOrCreateDatabaseFromPath(path);
+	public async Task OpenOrCreateDatabase() {
+		IsOpenOrCreateDatabaseButtonEnabled = false;
+		try {
+			var path = await DatabaseGui.NewOpenOrCreateDatabaseFileDialog(window, Path.GetDirectoryName(dbFilePath));
+			if (path != null) {
+				await OpenOrCreateDatabaseFromPath(path);
+			}
+		} finally {
+			IsOpenOrCreateDatabaseButtonEnabled = true;
 		}
 	}
 
 	public async Task OpenOrCreateDatabaseFromPath(string path) {
-		if (Db != null) {
-			Db = null;
+		dbFilePath = path;
+		
+		var db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, window, new SchemaUpgradeCallbacks(window));
+		if (db != null) {
+			DatabaseSelected?.Invoke(this, db);
+		}
+	}
+
+	private sealed class SchemaUpgradeCallbacks : ISchemaUpgradeCallbacks {
+		private readonly Window window;
+		
+		public SchemaUpgradeCallbacks(Window window) {
+			this.window = window;
 		}
 
-		dbFilePath = path;
-		Db = await DatabaseGui.TryOpenOrCreateDatabaseFromPath(path, window, CheckCanUpgradeDatabase);
+		public async Task<bool> CanUpgrade() {
+			return DialogResult.YesNo.Yes == await DatabaseGui.ShowCanUpgradeDatabaseDialog(window);
+		}
 
-		OnPropertyChanged(nameof(Db));
-		OnPropertyChanged(nameof(HasDatabase));
+		public async Task Start(int versionSteps, Func<ISchemaUpgradeCallbacks.IProgressReporter, Task> doUpgrade) {
+			async Task StartUpgrade(IReadOnlyList<IProgressCallback> callbacks) {
+				var reporter = new ProgressReporter(versionSteps, callbacks);
+				await reporter.NextVersion();
+				await Task.Delay(TimeSpan.FromMilliseconds(800));
+				await doUpgrade(reporter);
+				await Task.Delay(TimeSpan.FromMilliseconds(600));
+			}
+			
+			await new ProgressDialog { DataContext = new ProgressDialogModel("Upgrading Database", StartUpgrade, progressItems: 3) }.ShowProgressDialog(window);
+		}
+
+		private sealed class ProgressReporter : ISchemaUpgradeCallbacks.IProgressReporter {
+			private readonly IReadOnlyList<IProgressCallback> callbacks;
+			
+			private readonly int versionSteps;
+			private int versionProgress = 0;
+			
+			public ProgressReporter(int versionSteps, IReadOnlyList<IProgressCallback> callbacks) {
+				this.callbacks = callbacks;
+				this.versionSteps = versionSteps;
+			}
+
+			public async Task NextVersion() {
+				await callbacks[0].Update("Upgrading schema version...", versionProgress++, versionSteps);
+				await HideChildren(0);
+			}
+
+			public async Task MainWork(string message, int finishedItems, int totalItems) {
+				await callbacks[1].Update(message, finishedItems, totalItems);
+				await HideChildren(1);
+			}
+
+			public async Task SubWork(string message, int finishedItems, int totalItems) {
+				await callbacks[2].Update(message, finishedItems, totalItems);
+				await HideChildren(2);
+			}
+
+			private async Task HideChildren(int parentIndex) {
+				for (int i = parentIndex + 1; i < callbacks.Count; i++) {
+					await callbacks[i].Hide();
+				}
+			}
+		}
 	}
 
-	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 async Task ShowAboutDialog() {
+		await new AboutWindow { DataContext = new AboutWindowModel() }.ShowDialog(window);
 	}
 
 	public void Exit() {
 		window.Close();
 	}
-
-	public void Dispose() {
-		Db?.Dispose();
-		Db = null;
-	}
 }

app/Desktop/Program.cs

@@ -1,6 +1,8 @@
-using System.Globalization;
+using System;
+using System.Globalization;
 using System.Reflection;
 using Avalonia;
+using DHT.Utils.Logging;
 using DHT.Utils.Resources;
 
 namespace DHT.Desktop;
@@ -9,6 +11,7 @@ static class Program {
 	public static string Version { get; }
 	public static CultureInfo Culture { get; }
 	public static ResourceLoader Resources { get; }
+	public static Arguments Arguments { get; }
 
 	static Program() {
 		var assembly = Assembly.GetExecutingAssembly();
@@ -25,10 +28,21 @@ static class Program {
 		CultureInfo.DefaultThreadCurrentUICulture = CultureInfo.InvariantCulture;
 
 		Resources = new ResourceLoader(assembly);
+		Arguments = new Arguments(Environment.GetCommandLineArgs());
 	}
 
 	public static void Main(string[] args) {
-		BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
+		if (Arguments.Console && OperatingSystem.IsWindows()) {
+			WindowsConsole.AllocConsole();
+		}
+
+		try {
+			BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
+		} finally {
+			if (Arguments.Console && OperatingSystem.IsWindows()) {
+				WindowsConsole.FreeConsole();
+			}
+		}
 	}
 
 	private static AppBuilder BuildAvaloniaApp() {

app/Desktop/Server/ServerConfiguration.cs

@@ -0,0 +1,8 @@
+using DHT.Server.Service;
+
+namespace DHT.Desktop.Server;
+
+static class ServerConfiguration {
+	public static ushort Port { get; set; } = ServerUtils.FindAvailablePort(50000, 60000);
+	public static string Token { get; set; } = ServerUtils.GenerateRandomToken(20);
+}

app/Desktop/Server/ServerManager.cs

@@ -1,50 +0,0 @@
-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);
-
-	private static ServerManager? instance;
-
-	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!");
-			}
-
-			instance = this;
-		}
-
-		this.db = db;
-	}
-
-	public void Launch() {
-		ServerLauncher.Relaunch(Port, Token, db);
-	}
-
-	public void Relaunch(ushort port, string token) {
-		Port = port;
-		Token = token;
-		Launch();
-	}
-
-	public void Stop() {
-		ServerLauncher.Stop();
-	}
-
-	public void Dispose() {
-		Stop();
-
-		if (instance == this) {
-			instance = null;
-		}
-	}
-}

app/Directory.Build.props

@@ -2,7 +2,7 @@
   
   <PropertyGroup>
     <TargetFramework>net8.0</TargetFramework>
-    <LangVersion>11</LangVersion>
+    <LangVersion>12</LangVersion>
     <Nullable>enable</Nullable>
   </PropertyGroup>
   
@@ -19,9 +19,21 @@
   </PropertyGroup>
   
   <PropertyGroup>
+    <SuppressTrimAnalysisWarnings>false</SuppressTrimAnalysisWarnings>
     <PublishTrimmed>true</PublishTrimmed>
     <TrimMode>partial</TrimMode>
-    <JsonSerializerIsReflectionEnabledByDefault>true</JsonSerializerIsReflectionEnabledByDefault>
+    <EnableUnsafeBinaryFormatterSerialization>false</EnableUnsafeBinaryFormatterSerialization>
+    <EnableUnsafeUTF7Encoding>false</EnableUnsafeUTF7Encoding>
+    <EventSourceSupport>false</EventSourceSupport>
+    <HttpActivityPropagationSupport>false</HttpActivityPropagationSupport>
+    <JsonSerializerIsReflectionEnabledByDefault>false</JsonSerializerIsReflectionEnabledByDefault>
+  </PropertyGroup>
+  
+  <PropertyGroup>
+    <PublishSingleFile>true</PublishSingleFile>
+    <PublishReadyToRun>false</PublishReadyToRun>
+    <EnableCompressionInSingleFile>true</EnableCompressionInSingleFile>
+    <IncludeNativeLibrariesForSelfExtract>true</IncludeNativeLibrariesForSelfExtract>
   </PropertyGroup>
   
   <PropertyGroup Condition=" '$(Configuration)' == 'Release' ">

app/NuGet.Config

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+  <packageSources>
+    <add key="chylex's repository" value="https://nuget.chylex.com/feed/index.json" />
+  </packageSources>
+</configuration>

app/Resources/Tracker/scripts/state.js

@@ -48,6 +48,16 @@ const STATE = (function() {
 		});
 	};
 	
+	const getDate = function(date) {
+		if (date instanceof Date) {
+			return date;
+		}
+		else {
+			// noinspection JSUnresolvedReference
+			return date.toDate();
+		}
+	};
+	
 	const trackingStateChangedListeners = [];
 	let isTracking = false;
 	
@@ -69,8 +79,8 @@ const STATE = (function() {
 	 * @property {String} channel_id
 	 * @property {DiscordUser} author
 	 * @property {String} content
-	 * @property {Timestamp} timestamp
-	 * @property {Timestamp|null} editedTimestamp
+	 * @property {Date} timestamp
+	 * @property {Date|null} editedTimestamp
 	 * @property {DiscordAttachment[]} attachments
 	 * @property {Object[]} embeds
 	 * @property {DiscordMessageReaction[]} [reactions]
@@ -106,11 +116,6 @@ const STATE = (function() {
 	 * @property {Boolean} animated
 	 */
 	
-	/**
-	 * @name Timestamp
-	 * @property {Function} toDate
-	 */
-	
 	return {
 		setup(port, token) {
 			serverPort = port;
@@ -223,12 +228,12 @@ const STATE = (function() {
 					sender: msg.author.id,
 					channel: msg.channel_id,
 					text: msg.content,
-					timestamp: msg.timestamp.toDate().getTime()
+					timestamp: getDate(msg.timestamp).getTime()
 				};
 				
 				if (msg.editedTimestamp !== null) {
 					// noinspection JSUnusedGlobalSymbols
-					obj.editTimestamp = msg.editedTimestamp.toDate().getTime();
+					obj.editTimestamp = getDate(msg.editedTimestamp).getTime();
 				}
 				
 				if (msg.messageReference !== null) {

app/Resources/Viewer/index.html

@@ -2,15 +2,24 @@
 <html lang="en">
   <head>
     <meta charset="utf-8">
+    <meta name="referrer" content="no-referrer">
+    
     <title>Discord Offline History</title>
     
+    <link rel="icon" href="favicon.ico">
+    
+    <link rel="stylesheet" href="styles/main.css">
+    <link rel="stylesheet" href="styles/menu.css">
+    <link rel="stylesheet" href="styles/channels.css">
+    <link rel="stylesheet" href="styles/messages.css">
+    <link rel="stylesheet" href="styles/modal.css">
+    
     <script type="text/javascript">
-		window.DHT_EMBEDDED = "/*[ARCHIVE]*/";
-		/*[JS]*/
+		const query = new URLSearchParams(location.search);
+		window.DHT_SERVER_TOKEN = query.get("token");
+		window.DHT_SERVER_SESSION = query.get("session");
     </script>
-    <style>
-      /*[CSS]*/
-    </style>
+    <script type="module" src="scripts/bootstrap.mjs"></script>
   </head>
   <body>
     <div id="menu">
@@ -64,7 +73,9 @@
     </div>
     
     <div id="app">
-      <div id="channels"></div>
+      <div id="channels">
+        <div class="loading"></div>
+      </div>
       <div id="messages"></div>
     </div>
     

app/Resources/Viewer/scripts/bootstrap.js

@@ -1,39 +0,0 @@
-document.addEventListener("DOMContentLoaded", () => {
-	DISCORD.setup();
-	GUI.setup();
-	
-	GUI.onOptionMessagesPerPageChanged(() => {
-		STATE.setMessagesPerPage(GUI.getOptionMessagesPerPage());
-	});
-	
-	STATE.setMessagesPerPage(GUI.getOptionMessagesPerPage());
-	
-	GUI.onOptMessageFilterChanged(filter => {
-		STATE.setActiveFilter(filter);
-	});
-	
-	GUI.onNavigationButtonClicked(action => {
-		STATE.updateCurrentPage(action);
-	});
-	
-	STATE.onUsersRefreshed(users => {
-		GUI.updateUserList(users);
-	});
-	
-	STATE.onChannelsRefreshed((channels, selected) => {
-		GUI.updateChannelList(channels, selected, STATE.selectChannel);
-	});
-	
-	STATE.onMessagesRefreshed(messages => {
-		GUI.updateNavigation(STATE.getCurrentPage(), STATE.getPageCount());
-		GUI.updateMessageList(messages);
-		GUI.scrollMessagesToTop();
-	});
-	
-	try {
-		STATE.uploadFile(JSON.parse(window.DHT_EMBEDDED));
-	} catch (e) {
-		console.error(e);
-		alert("Could not parse embedded file, see console for details.");
-	}
-});

app/Resources/Viewer/scripts/bootstrap.mjs

@@ -0,0 +1,110 @@
+import discord from "./discord.mjs";
+import gui from "./gui.mjs";
+import state from "./state.mjs";
+
+window.DISCORD = discord;
+
+document.addEventListener("DOMContentLoaded", () => {
+	discord.setup();
+	gui.setup();
+	
+	gui.onOptionMessagesPerPageChanged(() => {
+		state.setMessagesPerPage(gui.getOptionMessagesPerPage());
+	});
+	
+	state.setMessagesPerPage(gui.getOptionMessagesPerPage());
+	
+	gui.onOptMessageFilterChanged(filter => {
+		state.setActiveFilter(filter);
+	});
+	
+	gui.onNavigationButtonClicked(action => {
+		state.updateCurrentPage(action);
+	});
+	
+	state.onUsersRefreshed(users => {
+		gui.updateUserList(users);
+	});
+	
+	state.onChannelsRefreshed((channels, selected) => {
+		gui.updateChannelList(channels, selected, state.selectChannel);
+	});
+	
+	state.onMessagesRefreshed(messages => {
+		gui.updateNavigation(state.getCurrentPage(), state.getPageCount());
+		gui.updateMessageList(messages);
+		gui.scrollMessagesToTop();
+	});
+	
+	async function fetchUrl(path, contentType) {
+		const response = await fetch("/" + path + "?token=" + encodeURIComponent(window.DHT_SERVER_TOKEN) + "&session=" + encodeURIComponent(window.DHT_SERVER_SESSION), {
+			method: "GET",
+			headers: {
+				"Content-Type": contentType,
+			},
+			credentials: "omit",
+			redirect: "error",
+		});
+		
+		if (!response.ok) {
+			throw "Unexpected response status: " + response.statusText;
+		}
+		
+		return response;
+	}
+	
+	async function processLines(response, callback) {
+		let body = "";
+		
+		for await (const chunk of response.body.pipeThrough(new TextDecoderStream("utf-8"))) {
+			body += chunk;
+			
+			let startIndex = 0;
+			
+			while (true) {
+				const endIndex = body.indexOf("\n", startIndex);
+				if (endIndex === -1) {
+					break;
+				}
+				
+				callback(body.substring(startIndex, endIndex));
+				startIndex = endIndex + 1;
+			}
+			
+			body = body.substring(startIndex);
+		}
+		
+		if (body !== "") {
+			callback(body);
+		}
+	}
+	
+	async function loadData() {
+		try {
+			const metadataResponse = await fetchUrl("get-viewer-metadata", "application/json");
+			const metadataJson = await metadataResponse.json();
+			
+			const messagesResponse = await fetchUrl("get-viewer-messages", "application/x-ndjson");
+			const messages = {};
+			
+			await processLines(messagesResponse, line => {
+				const message = JSON.parse(line);
+				const channel = message.c;
+				
+				const channelMessages = messages[channel] || (messages[channel] = {});
+				channelMessages[message.id] = message;
+				
+				delete message.id;
+				delete message.c;
+			});
+			
+			state.uploadFile(metadataJson, messages);
+		} catch (e) {
+			console.error(e);
+			alert("Could not load data, see console for details.");
+			document.querySelector("#channels > div.loading").remove();
+		}
+	}
+	
+	loadData();
+});

app/Resources/Viewer/scripts/discord.mjs

@@ -1,4 +1,10 @@
-const DISCORD = (function() {
+import discord from "./discord.mjs";
+import dom from "./dom.mjs";
+import template from "./template.mjs";
+import settings from "./settings.mjs";
+import state from "./state.mjs";
+
+export default (function() {
 	const regex = {
 		formatBold: /\*\*([\s\S]+?)\*\*(?!\*)/g,
 		formatItalic1: /\*([\s\S]+?)\*(?!\*)/g,
@@ -35,10 +41,24 @@ const DISCORD = (function() {
 	let templateReaction;
 	let templateReactionCustom;
 	
+	const fileUrlProcessor = function(serverToken) {
+		if (typeof serverToken === "string") {
+			return url => "/get-downloaded-file/" + encodeURIComponent(url) + "?token=" + encodeURIComponent(serverToken);
+		}
+		else {
+			return url => url;
+		}
+	}(window.DHT_SERVER_TOKEN);
+	
+	const getEmoji = function(name, id, extension) {
+		const tag = ":" + name + ":";
+		return "<img src='" + fileUrlProcessor("https://cdn.discordapp.com/emojis/" + id + "." + extension) + "' alt='" + tag + "' title='" + tag + "' class='emoji'>";
+	};
+	
 	const processMessageContents = function(contents) {
-		let processed = DOM.escapeHTML(contents.replace(regex.formatUrlNoEmbed, "$1"));
+		let processed = dom.escapeHTML(contents.replace(regex.formatUrlNoEmbed, "$1"));
 		
-		if (SETTINGS.enableFormatting) {
+		if (settings.enableFormatting) {
 			const escapeHtmlMatch = (full, match) => "&#" + match.charCodeAt(0) + ";";
 			
 			processed = processed
@@ -54,29 +74,33 @@ const DISCORD = (function() {
 				.replace(regex.formatStrike, "<s>$1</s>");
 		}
 		
-		const animatedEmojiExtension = SETTINGS.enableAnimatedEmoji ? "gif" : "png";
+		const animatedEmojiExtension = settings.enableAnimatedEmoji ? "gif" : "webp";
 		
 		// noinspection HtmlUnknownTarget
 		processed = processed
 			.replace(regex.formatUrl, "<a href='$1' target='_blank' rel='noreferrer'>$1</a>")
-			.replace(regex.mentionChannel, (full, match) => "<span class='link mention-chat'>#" + STATE.getChannelName(match) + "</span>")
-			.replace(regex.mentionUser, (full, match) => "<span class='link mention-user' title='#" + (STATE.getUserTag(match) || "????") + "'>@" + STATE.getUserName(match) + "</span>")
-			.replace(regex.customEmojiStatic, "<img src='https://cdn.discordapp.com/emojis/$2.png' alt=':$1:' title=':$1:' class='emoji'>")
-			.replace(regex.customEmojiAnimated, "<img src='https://cdn.discordapp.com/emojis/$2." + animatedEmojiExtension + "' alt=':$1:' title=':$1:' class='emoji'>");
+			.replace(regex.mentionChannel, (full, match) => "<span class='link mention-chat'>#" + state.getChannelName(match) + "</span>")
+			.replace(regex.mentionUser, (full, match) => "<span class='link mention-user' title='#" + (state.getUserTag(match) || "????") + "'>@" + state.getUserName(match) + "</span>")
+			.replace(regex.customEmojiStatic, (full, m1, m2) => getEmoji(m1, m2, "webp"))
+			.replace(regex.customEmojiAnimated, (full, m1, m2) => getEmoji(m1, m2, animatedEmojiExtension));
 		
 		return "<p>" + processed + "</p>";
 	};
 	
+	const getAvatarUrlObject = function(avatar) {
+		return { url: fileUrlProcessor("https://cdn.discordapp.com/avatars/" + avatar.id + "/" + avatar.path + ".webp") };
+	};
+	
 	const getImageEmbed = function(url, image) {
-		if (!SETTINGS.enableImagePreviews) {
+		if (!settings.enableImagePreviews) {
 			return "";
 		}
 		
 		if (image.width && image.height) {
-			return templateEmbedImageWithSize.apply({ url, src: image.url, width: image.width, height: image.height });
+			return templateEmbedImageWithSize.apply({ url: fileUrlProcessor(url), src: fileUrlProcessor(image.url), width: image.width, height: image.height });
 		}
 		else {
-			return templateEmbedImage.apply({ url, src: image.url });
+			return templateEmbedImage.apply({ url: fileUrlProcessor(url), src: fileUrlProcessor(image.url) });
 		}
 	};
 	
@@ -88,21 +112,21 @@ const DISCORD = (function() {
 	
 	return {
 		setup() {
-			templateChannelServer = new TEMPLATE([
-				"<div data-channel='{id}'>",
+			templateChannelServer = new template([
+				"<div class='channel' data-channel='{id}'>",
 				"<div class='info' title='{topic}'><strong class='name'>#{name}</strong>{nsfw}<span class='tag'>{msgcount}</span></div>",
 				"<span class='server'>{server.name} ({server.type})</span>",
 				"</div>"
 			].join(""));
 			
-			templateChannelPrivate = new TEMPLATE([
-				"<div data-channel='{id}'>",
+			templateChannelPrivate = new template([
+				"<div class='channel' data-channel='{id}'>",
 				"<div class='info'><strong class='name'>{name}</strong><span class='tag'>{msgcount}</span></div>",
 				"<span class='server'>({server.type})</span>",
 				"</div>"
 			].join(""));
 			
-			templateMessageNoAvatar = new TEMPLATE([
+			templateMessageNoAvatar = new template([
 				"<div>",
 				"<div class='reply-message'>{reply}</div>",
 				"<h2><strong class='username' title='#{user.tag}'>{user.name}</strong><span class='info time'>{timestamp}</span>{edit}{jump}</h2>",
@@ -111,7 +135,7 @@ const DISCORD = (function() {
 				"</div>"
 			].join(""));
 			
-			templateMessageWithAvatar = new TEMPLATE([
+			templateMessageWithAvatar = new template([
 				"<div>",
 				"<div class='reply-message reply-message-with-avatar'>{reply}</div>",
 				"<div class='avatar-wrapper'>",
@@ -125,50 +149,52 @@ const DISCORD = (function() {
 				"</div>"
 			].join(""));
 			
-			templateUserAvatar = new TEMPLATE([
-				"<img src='https://cdn.discordapp.com/avatars/{id}/{path}.webp?size=128' alt=''>"
+			// noinspection HtmlUnknownTarget
+			templateUserAvatar = new template([
+				"<img src='{url}' alt=''>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
-			templateAttachmentDownload = new TEMPLATE([
+			templateAttachmentDownload = new template([
 				"<a href='{url}' class='embed download'>Download {name}</a>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
-			templateEmbedImage = new TEMPLATE([
-				"<a href='{url}' class='embed thumbnail loading'><img src='{src}' alt='' onload='DISCORD.handleImageLoad(this)' onerror='DISCORD.handleImageLoadError(this)'></a><br>"
+			templateEmbedImage = new template([
+				"<a href='{url}' class='embed thumbnail loading'><img src='{src}' alt='' onload='window.DISCORD.handleImageLoad(this)' onerror='window.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>"
+			templateEmbedImageWithSize = new template([
+				"<a href='{url}' class='embed thumbnail loading'><img src='{src}' width='{width}' height='{height}' alt='' onload='window.DISCORD.handleImageLoad(this)' onerror='window.DISCORD.handleImageLoadError(this)'></a><br>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
-			templateEmbedRich = new TEMPLATE([
+			templateEmbedRich = new template([
 				"<div class='embed download'><a href='{url}' class='title'>{title}</a><p class='desc'>{description}</p></div>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
-			templateEmbedRichNoDescription = new TEMPLATE([
+			templateEmbedRichNoDescription = new template([
 				"<div class='embed download'><a href='{url}' class='title'>{title}</a></div>"
 			].join(""));
 			
 			// noinspection HtmlUnknownTarget
-			templateEmbedUrl = new TEMPLATE([
+			templateEmbedUrl = new template([
 				"<a href='{url}' class='embed download'>{url}</a>"
 			].join(""));
 			
-			templateEmbedUnsupported = new TEMPLATE([
+			templateEmbedUnsupported = new template([
 				"<div class='embed download'><p>(Unsupported embed)</p></div>"
 			].join(""));
 			
-			templateReaction = new TEMPLATE([
+			templateReaction = new template([
 				"<span class='reaction-wrapper'><span class='reaction-emoji'>{n}</span><span class='count'>{c}</span></span>"
 			].join(""));
 			
-			templateReactionCustom = new TEMPLATE([
-				"<span class='reaction-wrapper'><img src='https://cdn.discordapp.com/emojis/{id}.{ext}' alt=':{n}:' title=':{n}:' class='reaction-emoji-custom'><span class='count'>{c}</span></span>"
+			// noinspection HtmlUnknownTarget
+			templateReactionCustom = new template([
+				"<span class='reaction-wrapper'><img src='{url}' alt=':{n}:' title=':{n}:' class='reaction-emoji-custom'><span class='count'>{c}</span></span>"
 			].join(""));
 		},
 		
@@ -184,7 +210,7 @@ const DISCORD = (function() {
 		},
 		
 		isImageAttachment(attachment) {
-			const url = DOM.tryParseUrl(attachment.url);
+			const url = dom.tryParseUrl(attachment.url);
 			return url != null && isImageUrl(url);
 		},
 		
@@ -197,15 +223,15 @@ const DISCORD = (function() {
 		},
 		
 		getMessageHTML(message) { // noinspection FunctionWithInconsistentReturnsJS
-			return (SETTINGS.enableUserAvatars ? templateMessageWithAvatar : templateMessageNoAvatar).apply(message, (property, value) => {
+			return (settings.enableUserAvatars ? templateMessageWithAvatar : templateMessageNoAvatar).apply(message, (property, value) => {
 				if (property === "avatar") {
-					return value ? templateUserAvatar.apply(value) : "";
+					return value ? templateUserAvatar.apply(getAvatarUrlObject(value)) : "";
 				}
 				else if (property === "user.tag") {
 					return value ? value : "????";
 				}
 				else if (property === "timestamp") {
-					return DOM.getHumanReadableTime(value);
+					return dom.getHumanReadableTime(value);
 				}
 				else if (property === "contents") {
 					return value && value.length > 0 ? processMessageContents(value) : "";
@@ -242,22 +268,24 @@ const DISCORD = (function() {
 					}
 					
 					return value.map(attachment => {
-						if (!DISCORD.isImageAttachment(attachment) || !SETTINGS.enableImagePreviews) {
-							return templateAttachmentDownload.apply(attachment);
+						const url = fileUrlProcessor(attachment.url);
+						
+						if (!discord.isImageAttachment(attachment) || !settings.enableImagePreviews) {
+							return templateAttachmentDownload.apply({ url, name: attachment.name });
 						}
 						else if ("width" in attachment && "height" in attachment) {
-							return templateEmbedImageWithSize.apply({ url: attachment.url, src: attachment.url, width: attachment.width, height: attachment.height });
+							return templateEmbedImageWithSize.apply({ url, src: url, width: attachment.width, height: attachment.height });
 						}
 						else {
-							return templateEmbedImage.apply({ url: attachment.url, src: attachment.url });
+							return templateEmbedImage.apply({ url, src: url });
 						}
 					}).join("");
 				}
 				else if (property === "edit") {
-					return value ? "<span class='info edited'>Edited " + DOM.getHumanReadableTime(value) + "</span>" : "";
+					return value ? "<span class='info edited'>Edited " + dom.getHumanReadableTime(value) + "</span>" : "";
 				}
 				else if (property === "jump") {
-					return STATE.hasActiveFilter ? "<span class='info jump' data-jump='" + value + "'>Jump to message</span>" : "";
+					return state.hasActiveFilter ? "<span class='info jump' data-jump='" + value + "'>Jump to message</span>" : "";
 				}
 				else if (property === "reply") {
 					if (!value) {
@@ -265,7 +293,7 @@ const DISCORD = (function() {
 					}
 					
 					const user = "<span class='reply-username' title='#" + (value.user.tag ? value.user.tag : "????") + "'>" + value.user.name + "</span>";
-					const avatar = SETTINGS.enableUserAvatars && value.avatar ? "<span class='reply-avatar'>" + templateUserAvatar.apply(value.avatar) + "</span>" : "";
+					const avatar = settings.enableUserAvatars && value.avatar ? "<span class='reply-avatar'>" + templateUserAvatar.apply(getAvatarUrlObject(value.avatar)) + "</span>" : "";
 					const contents = value.contents ? "<span class='reply-contents'>" + processMessageContents(value.contents) + "</span>" : "";
 					
 					return "<span class='jump' data-jump='" + value.id + "'>Jump to reply</span><span class='user'>" + avatar + user + "</span>" + contents;
@@ -277,9 +305,10 @@ const DISCORD = (function() {
 					
 					return "<div class='reactions'>" + value.map(reaction => {
 						if ("id" in reaction){
-							// noinspection JSUnusedGlobalSymbols, JSUnresolvedVariable
-							reaction.ext = reaction.a && SETTINGS.enableAnimatedEmoji ? "gif" : "png";
-							return templateReactionCustom.apply(reaction);
+							const ext = reaction.a && settings.enableAnimatedEmoji ? "gif" : "webp";
+							const url = fileUrlProcessor("https://cdn.discordapp.com/emojis/" + reaction.id + "." + ext);
+							// noinspection JSUnusedGlobalSymbols
+							return templateReactionCustom.apply({ url, n: reaction.n, c: reaction.c });
 						}
 						else {
 							return templateReaction.apply(reaction);

app/Resources/Viewer/scripts/dom.mjs

@@ -8,9 +8,12 @@ const HTML_ENTITY_MAP = {
 
 const HTML_ENTITY_REGEX = /[&<>"']/g;
 
-class DOM {
+export default class {
 	/**
 	 * Returns a child element by its ID. Parent defaults to the entire document.
+	 * @param {string} id
+	 * @param {HTMLElement} [parent]
+	 * @returns {HTMLElement|null}
 	 */
 	static id(id, parent) {
 		return (parent || document).getElementById(id);
@@ -18,6 +21,9 @@ class DOM {
 	
 	/**
 	 * Returns an array of all child elements containing the specified class. Parent defaults to the entire document.
+	 * @param {string} cls
+	 * @param {HTMLElement} [parent]
+	 * @returns {HTMLElement[]}
 	 */
 	static cls(cls, parent) {
 		return Array.prototype.slice.call((parent || document).getElementsByClassName(cls));
@@ -25,6 +31,9 @@ class DOM {
 	
 	/**
 	 * Returns an array of all child elements that have the specified tag. Parent defaults to the entire document.
+	 * @param {string} tag
+	 * @param {HTMLElement} [parent]
+	 * @returns {HTMLElement[]}
 	 */
 	static tag(tag, parent) {
 		return Array.prototype.slice.call((parent || document).getElementsByTagName(tag));
@@ -32,6 +41,9 @@ class DOM {
 	
 	/**
 	 * Returns the first child element containing the specified class. Parent defaults to the entire document.
+	 * @param {string} cls
+	 * @param {HTMLElement} [parent]
+	 * @returns {HTMLElement}
 	 */
 	static fcls(cls, parent) {
 		return (parent || document).getElementsByClassName(cls)[0];

app/Resources/Viewer/scripts/gui.mjs

@@ -1,10 +1,16 @@
-const GUI = (function() {
+import dom from "./dom.mjs";
+import discord from "./discord.mjs";
+import settings from "./settings.mjs";
+import state from "./state.mjs";
+
+export default (function() {
 	let eventOnOptMessagesPerPageChanged;
 	let eventOnOptMessageFilterChanged;
 	let eventOnNavButtonClicked;
 	
 	const getActiveFilter = function() {
-		const active = DOM.fcls("active", DOM.id("opt-filter-list"));
+		/** @type HTMLSelectElement */
+		const active = dom.fcls("active", dom.id("opt-filter-list"));
 		
 		return active && active.value !== "" ? {
 			"type": active.getAttribute("data-filter-type"),
@@ -17,12 +23,12 @@ const GUI = (function() {
 	};
 	
 	const showModal = function(width, html) {
-		const dialog = DOM.id("dialog");
+		const dialog = dom.id("dialog");
 		dialog.innerHTML = html;
 		dialog.style.width = width + "px";
 		dialog.style.marginLeft = (-width / 2) + "px";
 		
-		DOM.id("modal").classList.add("visible");
+		dom.id("modal").classList.add("visible");
 		return dialog;
 	};
 	
@@ -38,9 +44,9 @@ const GUI = (function() {
 <label><input id='dht-cfg-animemoji' type='checkbox'> Animated Emoji</label><br>`);
 		
 		const setupCheckBox = function(id, settingName) {
-			const ele = DOM.id(id);
-			ele.checked = SETTINGS[settingName];
-			ele.addEventListener("change", () => SETTINGS[settingName] = ele.checked);
+			const ele = dom.id(id);
+			ele.checked = settings[settingName];
+			ele.addEventListener("change", () => settings[settingName] = ele.checked);
 		};
 		
 		setupCheckBox("dht-cfg-imgpreviews", "enableImagePreviews");
@@ -65,20 +71,20 @@ const GUI = (function() {
 		// ---------
 		
 		setup() {
-			const inputMessageFilter = DOM.id("opt-messages-filter");
-			const containerFilterList = DOM.id("opt-filter-list");
+			const inputMessageFilter = dom.id("opt-messages-filter");
+			const containerFilterList = dom.id("opt-filter-list");
 			
 			const resetActiveFilter = function() {
 				inputMessageFilter.value = "";
 				inputMessageFilter.dispatchEvent(new Event("change"));
 				
-				DOM.id("opt-filter-contents").value = "";
+				dom.id("opt-filter-contents").value = "";
 			};
 			
 			inputMessageFilter.value = ""; // required to prevent browsers from remembering old value
 			
 			inputMessageFilter.addEventListener("change", () => {
-				DOM.cls("active", containerFilterList).forEach(ele => ele.classList.remove("active"));
+				dom.cls("active", containerFilterList).forEach(ele => ele.classList.remove("active"));
 				
 				if (inputMessageFilter.value) {
 					containerFilterList.querySelector("[data-filter-type='" + inputMessageFilter.value + "']").classList.add("active");
@@ -91,11 +97,11 @@ const GUI = (function() {
 				ele.addEventListener(ele.tagName === "SELECT" ? "change" : "input", () => triggerFilterChanged());
 			});
 			
-			DOM.id("opt-messages-per-page").addEventListener("change", () => {
+			dom.id("opt-messages-per-page").addEventListener("change", () => {
 				eventOnOptMessagesPerPageChanged && eventOnOptMessagesPerPageChanged();
 			});
 			
-			DOM.tag("button", DOM.fcls("nav")).forEach(button => {
+			dom.tag("button", dom.fcls("nav")).forEach(button => {
 				button.disabled = true;
 				
 				button.addEventListener("click", () => {
@@ -103,34 +109,34 @@ const GUI = (function() {
 				});
 			});
 			
-			DOM.id("btn-settings").addEventListener("click", () => {
+			dom.id("btn-settings").addEventListener("click", () => {
 				showSettingsModal();
 			});
 			
-			DOM.id("btn-about").addEventListener("click", () => {
+			dom.id("btn-about").addEventListener("click", () => {
 				showInfoModal();
 			});
 			
-			DOM.id("messages").addEventListener("click", e => {
+			dom.id("messages").addEventListener("click", e => {
 				const jump = e.target.getAttribute("data-jump");
 				
 				if (jump) {
 					resetActiveFilter();
 					
-					const index = STATE.navigateToMessage(jump);
+					const index = state.navigateToMessage(jump);
 					
 					if (index === -1) {
 						alert("Message not found.");
 					}
 					else {
-						DOM.id("messages").children[index].scrollIntoView();
+						dom.id("messages").children[index].scrollIntoView();
 					}
 				}
 			});
 			
-			DOM.id("overlay").addEventListener("click", () => {
-				DOM.id("modal").classList.remove("visible");
-				DOM.id("dialog").innerHTML = "";
+			dom.id("overlay").addEventListener("click", () => {
+				dom.id("modal").classList.remove("visible");
+				dom.id("dialog").innerHTML = "";
 			});
 		},
 		
@@ -168,19 +174,19 @@ const GUI = (function() {
 		 */
 		getOptionMessagesPerPage() {
 			/** @type HTMLInputElement */
-			const messagesPerPage = DOM.id("opt-messages-per-page");
+			const messagesPerPage = dom.id("opt-messages-per-page");
 			return parseInt(messagesPerPage.value, 10);
 		},
 		
 		updateNavigation(currentPage, totalPages) {
-			DOM.id("nav-page-current").innerHTML = currentPage;
-			DOM.id("nav-page-total").innerHTML = totalPages || "?";
+			dom.id("nav-page-current").innerHTML = currentPage;
+			dom.id("nav-page-total").innerHTML = totalPages || "?";
 			
-			DOM.id("nav-first").disabled = currentPage === 1;
-			DOM.id("nav-prev").disabled = currentPage === 1;
-			DOM.id("nav-pick").disabled = (totalPages || 0) <= 1;
-			DOM.id("nav-next").disabled = currentPage === (totalPages || 1);
-			DOM.id("nav-last").disabled = currentPage === (totalPages || 1);
+			dom.id("nav-first").disabled = currentPage === 1;
+			dom.id("nav-prev").disabled = currentPage === 1;
+			dom.id("nav-pick").disabled = (totalPages || 0) <= 1;
+			dom.id("nav-next").disabled = currentPage === (totalPages || 1);
+			dom.id("nav-last").disabled = currentPage === (totalPages || 1);
 		},
 		
 		// --------------
@@ -191,7 +197,7 @@ const GUI = (function() {
 		 * Updates the channel list and sets up their click events. The callback is triggered whenever a channel is selected, and takes the channel ID as its argument.
 		 */
 		updateChannelList(channels, selected, callback) {
-			const eleChannels = DOM.id("channels");
+			const eleChannels = dom.id("channels");
 			
 			if (!channels) {
 				eleChannels.innerHTML = "";
@@ -201,11 +207,11 @@ const GUI = (function() {
 					channels = channels.filter(channel => channel.msgcount > 0);
 				}
 				
-				eleChannels.innerHTML = channels.map(channel => DISCORD.getChannelHTML(channel)).join("");
+				eleChannels.innerHTML = channels.map(channel => discord.getChannelHTML(channel)).join("");
 				
 				Array.prototype.forEach.call(eleChannels.children, ele => {
 					ele.addEventListener("click", () => {
-						const currentChannel = DOM.fcls("active", eleChannels);
+						const currentChannel = dom.fcls("active", eleChannels);
 						
 						if (currentChannel) {
 							currentChannel.classList.remove("active");
@@ -224,12 +230,12 @@ const GUI = (function() {
 		},
 		
 		updateMessageList(messages) {
-			DOM.id("messages").innerHTML = messages ? messages.map(message => DISCORD.getMessageHTML(message)).join("") : "";
+			dom.id("messages").innerHTML = messages ? messages.map(message => discord.getMessageHTML(message)).join("") : "";
 		},
 		
 		updateUserList(users) {
 			/** @type HTMLSelectElement */
-			const eleSelect = DOM.id("opt-filter-user");
+			const eleSelect = dom.id("opt-filter-user");
 			
 			while (eleSelect.length > 1) {
 				eleSelect.remove(1);
@@ -249,7 +255,7 @@ const GUI = (function() {
 		},
 		
 		scrollMessagesToTop() {
-			DOM.id("messages").scrollTop = 0;
+			dom.id("messages").scrollTop = 0;
 		}
 	};
 })();

app/Resources/Viewer/scripts/processor.mjs

@@ -1,16 +1,16 @@
-const PROCESSOR = {};
+import discord from "./discord.mjs";
 
 // ------------------------
 // Global filter generators
 // ------------------------
 
-PROCESSOR.FILTER = {
-	byUser: ((userindex) => message => message.u === userindex),
+const filter = {
+	byUser: ((user) => message => message.u === user),
 	byTime: ((timeStart, timeEnd) => message => message.t >= timeStart && message.t <= timeEnd),
 	byContents: ((substr) => message => ("m" in message ? message.m : "").indexOf(substr) !== -1),
 	byRegex: ((regex) => message => regex.test("m" in message ? message.m : "")),
-	withImages: (() => message => (message.e && message.e.some(embed => embed.type === "image")) || (message.a && message.a.some(DISCORD.isImageAttachment))),
-	withDownloads: (() => message => message.a && message.a.some(attachment => !DISCORD.isImageAttachment(attachment))),
+	withImages: (() => message => (message.e && message.e.some(embed => embed.type === "image")) || (message.a && message.a.some(discord.isImageAttachment))),
+	withDownloads: (() => message => message.a && message.a.some(attachment => !discord.isImageAttachment(attachment))),
 	withEmbeds: (() => message => message.e && message.e.length > 0),
 	withAttachments: (() => message => message.a && message.a.length > 0),
 	isEdited: (() => message => ("te" in message) ? message.te : (message.f & 1) === 1)
@@ -20,7 +20,7 @@ PROCESSOR.FILTER = {
 // Global sorters
 // --------------
 
-PROCESSOR.SORTER = {
+const sorter = {
 	oldestToNewest: (key1, key2) => {
 		if (key1.length === key2.length) {
 			return key1 > key2 ? 1 : key1 < key2 ? -1 : 0;
@@ -39,3 +39,8 @@ PROCESSOR.SORTER = {
 		}
 	}
 };
+
+export default {
+	FILTER: filter,
+	SORTER: sorter
+};

app/Resources/Viewer/scripts/settings.mjs

@@ -1,4 +1,4 @@
-const SETTINGS = (function() {
+export default (function() {
 	/**
 	 * @type {{}}
 	 * @property {Function} onSettingsChanged

app/Resources/Viewer/scripts/state.mjs

@@ -1,10 +1,12 @@
+import settings from "./settings.mjs";
+import processor from "./processor.mjs";
+
 // noinspection FunctionWithInconsistentReturnsJS
-const STATE = (function() {
+export default (function() {
 	/**
 	 * @type {{}}
 	 * @property {{}} users
-	 * @property {String[]} userindex
-	 * @property {{}[]} servers
+	 * @property {{}} servers
 	 * @property {{}} channels
 	 */
 	let loadedFileMeta;
@@ -17,20 +19,16 @@ const STATE = (function() {
 	let currentPage;
 	let messagesPerPage;
 	
-	const getUser = function(index) {
-		return loadedFileMeta.users[loadedFileMeta.userindex[index]] || { "name": "<unknown>" };
-	};
-	
-	const getUserId = function(index) {
-		return loadedFileMeta.userindex[index];
+	const getUser = function(id) {
+		return loadedFileMeta.users[id] || { "name": "<unknown>" };
 	};
 	
 	const getUserList = function() {
 		return loadedFileMeta ? loadedFileMeta.users : [];
 	};
 	
-	const getServer = function(index) {
-		return loadedFileMeta.servers[index] || { "name": "<unknown>", "type": "unknown" };
+	const getServer = function(id) {
+		return loadedFileMeta.servers[id] || { "name": "<unknown>", "type": "unknown" };
 	};
 	
 	const generateChannelHierarchy = function() {
@@ -173,7 +171,7 @@ const STATE = (function() {
 	};
 	
 	const getMessageChannel = function(id) {
-		for (const [ channel, messages ] of Object.entries(loadedFileData)) {
+		for (const [ channel, messages ] of Object.entries(loadedFileData)) { 
 			if (id in messages) {
 				return channel;
 			}
@@ -204,7 +202,7 @@ const STATE = (function() {
 			 */
 			const message = messages[key];
 			const user = getUser(message.u);
-			const avatar = user.avatar ? { id: getUserId(message.u), path: user.avatar } : null;
+			const avatar = user.avatar ? { id: message.u, path: user.avatar } : null;
 			
 			const obj = {
 				user,
@@ -232,7 +230,7 @@ const STATE = (function() {
 			if ("r" in message) {
 				const replyMessage = getMessageById(message.r);
 				const replyUser = replyMessage ? getUser(replyMessage.u) : null;
-				const replyAvatar = replyUser && replyUser.avatar ? { id: getUserId(replyMessage.u), path: replyUser.avatar } : null;
+				const replyAvatar = replyUser && replyUser.avatar ? { id: replyMessage.u, path: replyUser.avatar } : null;
 				
 				obj["reply"] = replyMessage ? {
 					"id": message.r,
@@ -290,20 +288,17 @@ const STATE = (function() {
 			eventOnUsersRefreshed = callback;
 		},
 		
-		/**
-		 * @param {{ meta, data }} file
-		 */
-		uploadFile(file) {
+		uploadFile(meta, data) {
 			if (loadedFileMeta != null) {
 				throw "A file is already loaded!";
 			}
 			
-			if (!file || typeof file.meta !== "object" || typeof file.data !== "object") {
+			if (typeof meta !== "object" || typeof data !== "object") {
 				throw "Invalid file format!";
 			}
 			
-			loadedFileMeta = file.meta;
-			loadedFileData = file.data;
+			loadedFileMeta = meta;
+			loadedFileData = data;
 			loadedMessages = null;
 			
 			selectedChannel = null;
@@ -313,7 +308,7 @@ const STATE = (function() {
 			triggerChannelsRefreshed();
 			triggerMessagesRefreshed();
 			
-			SETTINGS.onSettingsChanged(() => triggerMessagesRefreshed());
+			settings.onSettingsChanged(() => triggerMessagesRefreshed());
 		},
 		
 		getChannelName(channel) {
@@ -335,7 +330,7 @@ const STATE = (function() {
 			currentPage = 1;
 			selectedChannel = channel;
 			
-			loadedMessages = getFilteredMessageKeys(channel).sort(PROCESSOR.SORTER.oldestToNewest);
+			loadedMessages = getFilteredMessageKeys(channel).sort(processor.SORTER.oldestToNewest);
 			triggerMessagesRefreshed();
 		},
 		
@@ -416,23 +411,23 @@ const STATE = (function() {
 		setActiveFilter(filter) {
 			switch (filter ? filter.type : "") {
 				case "user":
-					filterFunction = PROCESSOR.FILTER.byUser(loadedFileMeta.userindex.indexOf(filter.value));
+					filterFunction = processor.FILTER.byUser(filter.value);
 					break;
 				
 				case "contents":
-					filterFunction = PROCESSOR.FILTER.byContents(filter.value);
+					filterFunction = processor.FILTER.byContents(filter.value);
 					break;
 				
 				case "withimages":
-					filterFunction = PROCESSOR.FILTER.withImages();
+					filterFunction = processor.FILTER.withImages();
 					break;
 				
 				case "withdownloads":
-					filterFunction = PROCESSOR.FILTER.withDownloads();
+					filterFunction = processor.FILTER.withDownloads();
 					break;
 				
 				case "edited":
-					filterFunction = PROCESSOR.FILTER.isEdited();
+					filterFunction = processor.FILTER.isEdited();
 					break;
 				
 				default:

app/Resources/Viewer/scripts/template.mjs

@@ -1,6 +1,8 @@
+import dom from "./dom.mjs";
+
 const TEMPLATE_REGEX = /{([^{}]+?)}/g;
 
-class TEMPLATE {
+export default class {
 	constructor(contents) {
 		this.contents = contents;
 	};
@@ -11,10 +13,10 @@ class TEMPLATE {
 			
 			if (processor) {
 				const updated = processor(match, value);
-				return typeof updated === "undefined" ? DOM.escapeHTML(value) : updated;
+				return typeof updated === "undefined" ? dom.escapeHTML(value) : updated;
 			}
 			
-			return DOM.escapeHTML(value);
+			return dom.escapeHTML(value);
 		});
 	}
 }

app/Resources/Viewer/styles/channels.css

@@ -3,18 +3,24 @@
   min-width: 215px;
   max-width: 300px;
   overflow-y: auto;
+  color: #eee;
   background-color: #1c1e22;
+  font-size: 15px;
 }
 
-#channels > div {
+#channels > div.loading {
+  margin: 0 auto;
+  width: 150px;
+  height: 150px;
+}
+
+#channels > div.channel {
   cursor: pointer;
   padding: 10px 12px;
-  color: #eee;
-  font-size: 15px;
   border-bottom: 1px solid #333333;
 }
 
-#channels > div:hover, #channels > div.active {
+#channels > div.channel:hover, #channels > div.channel.active {
   background-color: #282b30;
 }
 

app/Resources/Viewer/styles/main.css

@@ -11,3 +11,20 @@ body {
   display: flex;
   flex-direction: row;
 }
+
+.loading {
+  position: relative;
+  --loading-backdrop: rgba(0, 0, 0, 0);
+}
+
+.loading::after {
+  content: "";
+  background: var(--loading-backdrop)
+  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%;
+}

app/Resources/Viewer/styles/messages.css

@@ -107,23 +107,11 @@
 }
 
 .message .thumbnail {
-  position: relative;
+  --loading-backdrop: rgba(0, 0, 0, 0.75);
   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%;

app/Server/Data/Aggregations/DownloadStatusStatistics.cs

@@ -1,15 +1,19 @@
 namespace DHT.Server.Data.Aggregations;
 
 public sealed class DownloadStatusStatistics {
-	public int EnqueuedCount { get; internal set; }
-	public ulong EnqueuedSize { get; internal set; }
+	public int PendingCount { get; internal init; }
+	public ulong PendingTotalSize { get; internal init; }
+	public int PendingWithUnknownSizeCount { get; internal init; }
 
-	public int SuccessfulCount { get; internal set; }
-	public ulong SuccessfulSize { get; internal set; }
+	public int SuccessfulCount { get; internal init; }
+	public ulong SuccessfulTotalSize { get; internal init; }
+	public int SuccessfulWithUnknownSizeCount { get; internal init; }
 
-	public int FailedCount { get; internal set; }
-	public ulong FailedSize { get; internal set; }
-
-	public int SkippedCount { get; internal set; }
-	public ulong SkippedSize { get; internal set; }
+	public int FailedCount { get; internal init; }
+	public ulong FailedTotalSize { get; internal init; }
+	public int FailedWithUnknownSizeCount { get; internal init; }
+	
+	public int SkippedCount { get; internal init; }
+	public ulong SkippedTotalSize { get; internal init; }
+	public int SkippedWithUnknownSizeCount { get; internal init; }
 }

app/Server/Data/Download.cs

@@ -1,33 +1,17 @@
-using System;
-using System.Net;
-using DHT.Server.Download;
-
 namespace DHT.Server.Data;
 
-public readonly struct Download {
-	internal static Download NewSuccess(DownloadItem item, byte[] data) {
-		return new Download(item.NormalizedUrl, item.DownloadUrl, DownloadStatus.Success, (ulong) Math.Max(data.LongLength, 0), data);
-	}
-
-	internal static Download NewFailure(DownloadItem item, HttpStatusCode? statusCode, ulong size) {
-		return new Download(item.NormalizedUrl, item.DownloadUrl, statusCode.HasValue ? (DownloadStatus) (int) statusCode : DownloadStatus.GenericError, size);
-	}
-
+public sealed class Download {
 	public string NormalizedUrl { get; }
 	public string DownloadUrl { get; }
 	public DownloadStatus Status { get; }
-	public ulong Size { get; }
-	public byte[]? Data { get; }
+	public string? Type { get; }
+	public ulong? Size { get; }
 
-	internal Download(string normalizedUrl, string downloadUrl, DownloadStatus status, ulong size, byte[]? data = null) {
+	internal Download(string normalizedUrl, string downloadUrl, DownloadStatus status, string? type, ulong? size) {
 		NormalizedUrl = normalizedUrl;
 		DownloadUrl = downloadUrl;
 		Status = status;
+		Type = type;
 		Size = size;
-		Data = data;
-	}
-
-	internal Download WithData(byte[] data) {
-		return new Download(NormalizedUrl, DownloadUrl, Status, Size, data);
 	}
 }

app/Server/Data/DownloadStatus.cs

@@ -6,7 +6,9 @@ namespace DHT.Server.Data;
 /// Extends <see cref="HttpStatusCode"/> with custom status codes in the range 0-99.
 /// </summary>
 public enum DownloadStatus {
-	Enqueued = 0,
+	Pending = 0,
 	GenericError = 1,
+	Downloading = 2,
+	LastCustomCode = 99,
 	Success = HttpStatusCode.OK
 }

app/Server/Data/DownloadedAttachment.cs

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

app/Server/Data/Embeds/DiscordEmbedJson.cs

@@ -0,0 +1,17 @@
+namespace DHT.Server.Data.Embeds;
+
+sealed class DiscordEmbedJson {
+	public string? Type { get; set; }
+	public string? Url { get; set; }
+	
+	public JsonImage? Image { get; set; }
+	public JsonImage? Thumbnail { get; set; }
+	public JsonImage? Video { get; set; }
+
+	public sealed class JsonImage {
+		public string? Url { get; set; }
+		public string? ProxyUrl { get; set; }
+		public int? Width { get; set; }
+		public int? Height { get; set; }
+	}
+}

app/Server/Data/Embeds/DiscordEmbedJsonContext.cs

@@ -0,0 +1,7 @@
+using System.Text.Json.Serialization;
+
+namespace DHT.Server.Data.Embeds;
+
+[JsonSourceGenerationOptions(PropertyNamingPolicy = JsonKnownNamingPolicy.SnakeCaseLower, GenerationMode = JsonSourceGenerationMode.Default)]
+[JsonSerializable(typeof(DiscordEmbedJson))]
+sealed partial class DiscordEmbedJsonContext : JsonSerializerContext;

app/Server/Data/Filters/AttachmentFilter.cs

@@ -1,15 +0,0 @@
-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

@@ -3,8 +3,10 @@ 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 HashSet<DownloadStatus>? IncludeStatuses { get; set; } = null;
+	public HashSet<DownloadStatus>? ExcludeStatuses { get; set; } = null;
+	
+	public ulong? MaxBytes { get; set; } = null;
 
-	public bool IsEmpty => IncludeStatuses == null && ExcludeStatuses == null;
+	public bool IsEmpty => IncludeStatuses == null && ExcludeStatuses == null && MaxBytes == null;
 }

app/Server/Data/Message.cs

@@ -10,7 +10,7 @@ public readonly struct Message {
 	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; }
+	public ImmutableList<Attachment> Attachments { get; init; }
+	public ImmutableList<Embed> Embeds { get; init; }
+	public ImmutableList<Reaction> Reactions { get; init; }
 }

app/Server/Database/DatabaseExtensions.cs

@@ -1,29 +1,34 @@
 using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
 using DHT.Server.Data;
 
 namespace DHT.Server.Database;
 
 public static class DatabaseExtensions {
-	public static 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());
+	public static async Task AddFrom(this IDatabaseFile target, IDatabaseFile source) {
+		await target.Users.Add(await source.Users.Get().ToListAsync());
+		await target.Servers.Add(await source.Servers.Get().ToListAsync());
+		await target.Channels.Add(await source.Channels.Get().ToListAsync());
 
-		foreach (var download in source.GetDownloadsWithoutData()) {
-			target.AddDownload(download.Status == DownloadStatus.Success ? source.GetDownloadWithData(download) : download);
+		const int MessageBatchSize = 100;
+		List<Message> batchedMessages = new (MessageBatchSize);
+		
+		await foreach (var message in source.Messages.Get()) {
+			batchedMessages.Add(message);
+
+			if (batchedMessages.Count >= MessageBatchSize) {
+				await target.Messages.Add(batchedMessages);
+				batchedMessages.Clear();
+			}
 		}
-	}
+		
+		await target.Messages.Add(batchedMessages);
 
-	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);
+		await foreach (var download in source.Downloads.Get()) {
+			if (download.Status != DownloadStatus.Success || !await source.Downloads.GetDownloadData(download.NormalizedUrl, stream => target.Downloads.AddDownload(download, stream))) {
+				await target.Downloads.AddDownload(download, stream: null);
+			}
 		}
 	}
 }

app/Server/Database/DatabaseStatistics.cs

@@ -1,46 +0,0 @@
-using DHT.Utils.Models;
-
-namespace DHT.Server.Database;
-
-/// <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 TotalServers {
-		get => totalServers;
-		internal set => Change(ref totalServers, value);
-	}
-
-	public long TotalChannels {
-		get => totalChannels;
-		internal set => Change(ref totalChannels, value);
-	}
-
-	public long TotalUsers {
-		get => totalUsers;
-		internal set => Change(ref totalUsers, value);
-	}
-
-	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

@@ -1,11 +0,0 @@
-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; }
-}

app/Server/Database/DummyDatabaseFile.cs

@@ -1,90 +1,28 @@
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-using DHT.Server.Data;
-using DHT.Server.Data.Aggregations;
-using DHT.Server.Data.Filters;
-using DHT.Server.Download;
+using System.Threading.Tasks;
+using DHT.Server.Database.Repositories;
 
 namespace DHT.Server.Database;
 
 [SuppressMessage("ReSharper", "ArrangeObjectCreationWhenTypeNotEvident")]
-public sealed class DummyDatabaseFile : IDatabaseFile {
-	public static DummyDatabaseFile Instance { get; } = new();
+sealed class DummyDatabaseFile : IDatabaseFile {
+	public static DummyDatabaseFile Instance { get; } = new ();
 
 	public string Path => "";
-	public DatabaseStatistics Statistics { get; } = new();
-
+	
+	public IUserRepository Users { get; } = new IUserRepository.Dummy();
+	public IServerRepository Servers { get; } = new IServerRepository.Dummy();
+	public IChannelRepository Channels { get; } = new IChannelRepository.Dummy();
+	public IMessageRepository Messages { get; } = new IMessageRepository.Dummy();
+	public IDownloadRepository Downloads { get; } = new IDownloadRepository.Dummy();
+	
 	private DummyDatabaseFile() {}
 
-	public DatabaseStatisticsSnapshot SnapshotStatistics() {
-		return new();
+	public Task Vacuum() {
+		return Task.CompletedTask;
 	}
 
-	public void AddServer(Data.Server server) {}
-
-	public List<Data.Server> GetAllServers() {
-		return new();
+	public ValueTask DisposeAsync() {
+		return ValueTask.CompletedTask;
 	}
-
-	public void AddChannel(Channel channel) {}
-
-	public List<Channel> GetAllChannels() {
-		return new();
-	}
-
-	public void AddUsers(User[] users) {}
-
-	public List<User> GetAllUsers() {
-		return new();
-	}
-
-	public void AddMessages(Message[] messages) {}
-
-	public int CountMessages(MessageFilter? filter = null) {
-		return 0;
-	}
-
-	public List<Message> GetMessages(MessageFilter? filter = null) {
-		return new();
-	}
-
-	public HashSet<ulong> GetMessageIds(MessageFilter? filter = null) {
-		return new();
-	}
-
-	public void RemoveMessages(MessageFilter filter, FilterRemovalMode mode) {}
-
-	public int CountAttachments(AttachmentFilter? filter = null) {
-		return new();
-	}
-
-	public List<Data.Download> GetDownloadsWithoutData() {
-		return new();
-	}
-
-	public Data.Download GetDownloadWithData(Data.Download download) {
-		return download;
-	}
-
-	public DownloadedAttachment? GetDownloadedAttachment(string url) {
-		return null;
-	}
-
-	public void AddDownload(Data.Download download) {}
-
-	public void EnqueueDownloadItems(AttachmentFilter? filter = null) {}
-
-	public List<DownloadItem> GetEnqueuedDownloadItems(int count) {
-		return new();
-	}
-
-	public void RemoveDownloadItems(DownloadItemFilter? filter, FilterRemovalMode mode) {}
-
-	public DownloadStatusStatistics GetDownloadStatusStatistics() {
-		return new();
-	}
-
-	public void Vacuum() {}
-
-	public void Dispose() {}
 }

app/Server/Database/Exceptions/DatabaseTooNewException.cs

@@ -5,9 +5,9 @@ namespace DHT.Server.Database.Exceptions;
 
 public sealed class DatabaseTooNewException : Exception {
 	public int DatabaseVersion { get; }
-	public int CurrentVersion => Schema.Version;
+	public int CurrentVersion => SqliteSchema.Version;
 
-	internal DatabaseTooNewException(int databaseVersion) : base("Database is too new: " + databaseVersion + " > " + Schema.Version) {
+	internal DatabaseTooNewException(int databaseVersion) : base("Database is too new: " + databaseVersion + " > " + SqliteSchema.Version) {
 		this.DatabaseVersion = databaseVersion;
 	}
 }

app/Server/Database/Export/Snowflake.cs

@@ -0,0 +1,5 @@
+namespace DHT.Server.Database.Export;
+
+readonly record struct Snowflake(ulong Id) {
+	public static implicit operator Snowflake(ulong id) => new (id);
+}

app/Server/Database/Export/SnowflakeJsonSerializer.cs

@@ -0,0 +1,23 @@
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace DHT.Server.Database.Export;
+
+sealed class SnowflakeJsonSerializer : JsonConverter<Snowflake> {
+	public override Snowflake Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
+		return new Snowflake(ulong.Parse(reader.GetString()!));
+	}
+
+	public override void Write(Utf8JsonWriter writer, Snowflake value, JsonSerializerOptions options) {
+		writer.WriteStringValue(value.Id.ToString());
+	}
+
+	public override Snowflake ReadAsPropertyName(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
+		return new Snowflake(ulong.Parse(reader.GetString()!));
+	}
+
+	public override void WriteAsPropertyName(Utf8JsonWriter writer, Snowflake value, JsonSerializerOptions options) {
+		writer.WritePropertyName(value.Id.ToString());
+	}
+}

app/Server/Database/Export/Strategy/IViewerExportStrategy.cs

@@ -1,7 +0,0 @@
-using DHT.Server.Data;
-
-namespace DHT.Server.Database.Export.Strategy;
-
-public interface IViewerExportStrategy {
-	string GetAttachmentUrl(Attachment attachment);
-}

app/Server/Database/Export/Strategy/LiveViewerExportStrategy.cs

@@ -1,18 +0,0 @@
-using System.Net;
-using DHT.Server.Data;
-
-namespace DHT.Server.Database.Export.Strategy;
-
-public sealed class LiveViewerExportStrategy : IViewerExportStrategy {
-	private readonly string safePort;
-	private readonly string safeToken;
-
-	public LiveViewerExportStrategy(ushort port, string token) {
-		this.safePort = port.ToString();
-		this.safeToken = WebUtility.UrlEncode(token);
-	}
-
-	public string GetAttachmentUrl(Attachment attachment) {
-		return "http://127.0.0.1:" + safePort + "/get-attachment/" + WebUtility.UrlEncode(attachment.NormalizedUrl) + "?token=" + safeToken;
-	}
-}

app/Server/Database/Export/Strategy/StandaloneViewerExportStrategy.cs

@@ -1,18 +0,0 @@
-using DHT.Server.Data;
-
-namespace DHT.Server.Database.Export.Strategy;
-
-public sealed class StandaloneViewerExportStrategy : IViewerExportStrategy {
-	public static StandaloneViewerExportStrategy Instance { get; } = new ();
-
-	private StandaloneViewerExportStrategy() {}
-
-	public string GetAttachmentUrl(Attachment attachment) {
-		// The normalized URL will not load files from Discord CDN once the time limit is enforced.
-		
-		// The downloaded URL would work, but only for a limited time, so it is better for the links to not work
-		// rather than give users a false sense of security.
-		
-		return attachment.NormalizedUrl;
-	}
-}

app/Server/Database/Export/ViewerJson.cs

@@ -0,0 +1,91 @@
+using System.Collections.Generic;
+using System.Text.Json.Serialization;
+
+namespace DHT.Server.Database.Export;
+
+static class ViewerJson {
+	public sealed class JsonMeta {
+		public required Dictionary<Snowflake, JsonUser> Users { get; init; }
+		public required Dictionary<Snowflake, JsonServer> Servers { get; init; }
+		public required Dictionary<Snowflake, JsonChannel> Channels { get; init; }
+	}
+	
+	public sealed class JsonUser {
+		public required string Name { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? Avatar { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? Tag { get; init; }
+	}
+
+	public sealed class JsonServer {
+		public required string Name { get; init; }
+		public required string Type { get; init; }
+	}
+
+	public sealed class JsonChannel {
+		public required Snowflake Server { get; init; }
+		public required string Name { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? Parent { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public int? Position { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? Topic { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public bool? Nsfw { get; init; }
+	}
+
+	public sealed class JsonMessage {
+		public required Snowflake Id { get; init; }
+		public required Snowflake C { get; init; }
+		public required Snowflake U { get; init; }
+		public required long T { get; init; }
+
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? M { get; init; }
+
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public long? Te { get; init; }
+
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? R { get; init; }
+
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public JsonMessageAttachment[]? A { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string[]? E { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public JsonMessageReaction[]? Re { get; init; }
+	}
+
+	public sealed class JsonMessageAttachment {
+		public required string Url { get; init; }
+		public required string Name { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public int? Width { get; set; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public int? Height { get; set; }
+	}
+
+	public sealed class JsonMessageReaction {
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? Id { get; init; }
+		
+		[JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+		public string? N { get; init; }
+
+		public required bool A { get; init; }
+		public required int C { get; init; }
+	}
+}

app/Server/Database/Export/ViewerJsonExport.cs

@@ -2,214 +2,148 @@ using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
+using System.Runtime.CompilerServices;
 using System.Text.Json;
+using System.Threading;
 using System.Threading.Tasks;
 using DHT.Server.Data;
 using DHT.Server.Data.Filters;
-using DHT.Server.Database.Export.Strategy;
 using DHT.Utils.Logging;
 
 namespace DHT.Server.Database.Export;
 
-public static class ViewerJsonExport {
+static class ViewerJsonExport {
 	private static readonly Log Log = Log.ForType(typeof(ViewerJsonExport));
 
-	public static async Task Generate(Stream stream, IViewerExportStrategy strategy, IDatabaseFile db, MessageFilter? filter = null) {
+	public static async Task GetMetadata(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
 		var perf = Log.Start();
 
-		var includedUserIds = new HashSet<ulong>();
-		var includedChannelIds = new HashSet<ulong>();
+		var includedChannels = new List<Channel>();
 		var includedServerIds = new HashSet<ulong>();
 
-		var includedMessages = db.GetMessages(filter);
-		var includedChannels = new List<Channel>();
+		var channelIdFilter = filter?.ChannelIds;
 
-		foreach (var message in includedMessages) {
-			includedUserIds.Add(message.Sender);
-			includedChannelIds.Add(message.Channel);
-		}
-
-		foreach (var channel in db.GetAllChannels()) {
-			if (includedChannelIds.Contains(channel.Id)) {
+		await foreach (var channel in db.Channels.Get(cancellationToken)) {
+			if (channelIdFilter == null || channelIdFilter.Contains(channel.Id)) {
 				includedChannels.Add(channel);
 				includedServerIds.Add(channel.Server);
 			}
 		}
 
-		var users = GenerateUserList(db, includedUserIds, out var userindex, out var userIndices);
-		var servers = GenerateServerList(db, includedServerIds, out var serverindex);
-		var channels = GenerateChannelList(includedChannels, serverindex);
+		var users = await GenerateUserList(db, cancellationToken);
+		var servers = await GenerateServerList(db, includedServerIds, cancellationToken);
+		var channels = GenerateChannelList(includedChannels);
+
+		var meta = new ViewerJson.JsonMeta {
+			Users = users,
+			Servers = servers,
+			Channels = channels
+		};
 
 		perf.Step("Collect database data");
 
-		var value = new {
-			meta = new { users, userindex, servers, channels },
-			data = GenerateMessageList(includedMessages, userIndices, strategy),
-		};
-
-		perf.Step("Generate value object");
-
-		var opts = new JsonSerializerOptions();
-		opts.Converters.Add(new ViewerJsonSnowflakeSerializer());
-
-		await JsonSerializer.SerializeAsync(stream, value, opts);
+		await JsonSerializer.SerializeAsync(stream, meta, ViewerJsonMetadataContext.Default.JsonMeta, cancellationToken);
 
 		perf.Step("Serialize to JSON");
 		perf.End();
 	}
 
-	private static Dictionary<string, object> GenerateUserList(IDatabaseFile db, HashSet<ulong> userIds, out List<string> userindex, out Dictionary<ulong, object> userIndices) {
-		var users = new Dictionary<string, object>();
-		userindex = new List<string>();
-		userIndices = new Dictionary<ulong, object>();
+	public static async Task GetMessages(Stream stream, IDatabaseFile db, MessageFilter? filter = null, CancellationToken cancellationToken = default) {
+		var perf = Log.Start();
 
-		foreach (var user in db.GetAllUsers()) {
-			var id = user.Id;
-			if (!userIds.Contains(id)) {
-				continue;
-			}
+		ReadOnlyMemory<byte> newLine = "\n"u8.ToArray();
+		
+		await foreach(var message in GenerateMessageList(db, filter, cancellationToken)) {
+			await JsonSerializer.SerializeAsync(stream, message, ViewerJsonMessageContext.Default.JsonMessage, cancellationToken);
+			await stream.WriteAsync(newLine, cancellationToken);
+		}
 
-			var obj = new Dictionary<string, object> {
-				["name"] = user.Name
+		perf.Step("Generate and serialize messages to JSON");
+		perf.End();
+	}
+
+	private static async Task<Dictionary<Snowflake, ViewerJson.JsonUser>> GenerateUserList(IDatabaseFile db, CancellationToken cancellationToken) {
+		var users = new Dictionary<Snowflake, ViewerJson.JsonUser>();
+
+		await foreach (var user in db.Users.Get(cancellationToken)) {
+			users[user.Id] = new ViewerJson.JsonUser {
+				Name = user.Name,
+				Avatar = user.AvatarUrl,
+				Tag = user.Discriminator
 			};
-
-			if (user.AvatarUrl != null) {
-				obj["avatar"] = user.AvatarUrl;
-			}
-
-			if (user.Discriminator != null) {
-				obj["tag"] = user.Discriminator;
-			}
-
-			var idStr = id.ToString();
-			userIndices[id] = users.Count;
-			userindex.Add(idStr);
-			users[idStr] = obj;
 		}
 
 		return users;
 	}
 
-	private static List<object> GenerateServerList(IDatabaseFile db, HashSet<ulong> serverIds, out Dictionary<ulong, object> serverIndices) {
-		var servers = new List<object>();
-		serverIndices = new Dictionary<ulong, object>();
+	private static async Task<Dictionary<Snowflake, ViewerJson.JsonServer>> GenerateServerList(IDatabaseFile db, HashSet<ulong> serverIds, CancellationToken cancellationToken) {
+		var servers = new Dictionary<Snowflake, ViewerJson.JsonServer>();
 
-		foreach (var server in db.GetAllServers()) {
-			var id = server.Id;
-			if (!serverIds.Contains(id)) {
+		await foreach (var server in db.Servers.Get(cancellationToken)) {
+			if (!serverIds.Contains(server.Id)) {
 				continue;
 			}
 
-			serverIndices[id] = servers.Count;
-			servers.Add(new Dictionary<string, object> {
-				["name"] = server.Name,
-				["type"] = ServerTypes.ToJsonViewerString(server.Type),
-			});
+			servers[server.Id] = new ViewerJson.JsonServer {
+				Name = server.Name,
+				Type = ServerTypes.ToJsonViewerString(server.Type)
+			};
 		}
 
 		return servers;
 	}
 
-	private static Dictionary<string, object> GenerateChannelList(List<Channel> includedChannels, Dictionary<ulong, object> serverIndices) {
-		var channels = new Dictionary<string, object>();
+	private static Dictionary<Snowflake, ViewerJson.JsonChannel> GenerateChannelList(List<Channel> includedChannels) {
+		var channels = new Dictionary<Snowflake, ViewerJson.JsonChannel>();
 
 		foreach (var channel in includedChannels) {
-			var obj = new Dictionary<string, object> {
-				["server"] = serverIndices[channel.Server],
-				["name"] = channel.Name,
+			channels[channel.Id] = new ViewerJson.JsonChannel {
+				Server = channel.Server,
+				Name = channel.Name,
+				Parent = channel.ParentId?.ToString(),
+				Position = channel.Position,
+				Topic = channel.Topic,
+				Nsfw = channel.Nsfw
 			};
-
-			if (channel.ParentId != null) {
-				obj["parent"] = channel.ParentId;
-			}
-
-			if (channel.Position != null) {
-				obj["position"] = channel.Position;
-			}
-
-			if (channel.Topic != null) {
-				obj["topic"] = channel.Topic;
-			}
-
-			if (channel.Nsfw != null) {
-				obj["nsfw"] = channel.Nsfw;
-			}
-
-			channels[channel.Id.ToString()] = obj;
 		}
 
 		return channels;
 	}
 
-	private static Dictionary<string, Dictionary<string, object>> GenerateMessageList( List<Message> includedMessages, Dictionary<ulong, object> userIndices, IViewerExportStrategy strategy) {
-		var data = new Dictionary<string, Dictionary<string, object>>();
+	private static async IAsyncEnumerable<ViewerJson.JsonMessage> GenerateMessageList(IDatabaseFile db, MessageFilter? filter, [EnumeratorCancellation] CancellationToken cancellationToken) {
+		await foreach (var message in db.Messages.Get(filter, cancellationToken)) {
+			yield return new ViewerJson.JsonMessage {
+				Id = message.Id,
+				C = message.Channel,
+				U = message.Sender,
+				T = message.Timestamp,
+				M = string.IsNullOrEmpty(message.Text) ? null : message.Text,
+				Te = message.EditTimestamp,
+				R = message.RepliedToId?.ToString(),
 
-		foreach (var grouping in includedMessages.GroupBy(static message => message.Channel)) {
-			var channel = grouping.Key.ToString();
-			var channelData = new Dictionary<string, object>();
+				A = message.Attachments.IsEmpty ? null : message.Attachments.Select(static attachment => {
+					var a = new ViewerJson.JsonMessageAttachment {
+						Url = attachment.DownloadUrl,
+						Name = Uri.TryCreate(attachment.NormalizedUrl, UriKind.Absolute, out var uri) ? Path.GetFileName(uri.LocalPath) : attachment.NormalizedUrl
+					};
 
-			foreach (var message in grouping) {
-				var obj = new Dictionary<string, object> {
-					["u"] = userIndices[message.Sender],
-					["t"] = message.Timestamp,
-				};
+					if (attachment is { Width: not null, Height: not null }) {
+						a.Width = attachment.Width;
+						a.Height = attachment.Height;
+					}
 
-				if (!string.IsNullOrEmpty(message.Text)) {
-					obj["m"] = message.Text;
-				}
+					return a;
+				}).ToArray(),
 
-				if (message.EditTimestamp != null) {
-					obj["te"] = message.EditTimestamp;
-				}
+				E = message.Embeds.IsEmpty ? null : message.Embeds.Select(static embed => embed.Json).ToArray(),
 
-				if (message.RepliedToId != null) {
-					obj["r"] = message.RepliedToId.Value;
-				}
-
-				if (!message.Attachments.IsEmpty) {
-					obj["a"] = message.Attachments.Select(attachment => {
-						var a = new Dictionary<string, object> {
-							{ "url", strategy.GetAttachmentUrl(attachment) },
-							{ "name", Uri.TryCreate(attachment.NormalizedUrl, UriKind.Absolute, out var uri) ? Path.GetFileName(uri.LocalPath) : attachment.NormalizedUrl },
-						};
-
-						if (attachment is { Width: not null, Height: not null }) {
-							a["width"] = attachment.Width;
-							a["height"] = attachment.Height;
-						}
-
-						return a;
-					}).ToArray();
-				}
-
-				if (!message.Embeds.IsEmpty) {
-					obj["e"] = message.Embeds.Select(static embed => embed.Json).ToArray();
-				}
-
-				if (!message.Reactions.IsEmpty) {
-					obj["re"] = message.Reactions.Select(static reaction => {
-						var r = new Dictionary<string, object>();
-
-						if (reaction.EmojiId != null) {
-							r["id"] = reaction.EmojiId.Value;
-						}
-
-						if (reaction.EmojiName != null) {
-							r["n"] = reaction.EmojiName;
-						}
-
-						r["a"] = reaction.EmojiFlags.HasFlag(EmojiFlags.Animated);
-						r["c"] = reaction.Count;
-						return r;
-					}).ToArray();
-				}
-
-				channelData[message.Id.ToString()] = obj;
-			}
-
-			data[channel] = channelData;
+				Re = message.Reactions.IsEmpty ? null : message.Reactions.Select(static reaction => new ViewerJson.JsonMessageReaction {
+					Id = reaction.EmojiId?.ToString(),
+					N = reaction.EmojiName,
+					A = reaction.EmojiFlags.HasFlag(EmojiFlags.Animated),
+					C = reaction.Count
+				}).ToArray()
+			};
 		}
-
-		return data;
 	}
 }

app/Server/Database/Export/ViewerJsonMessageContext.cs

@@ -0,0 +1,11 @@
+using System.Text.Json.Serialization;
+
+namespace DHT.Server.Database.Export;
+
+[JsonSourceGenerationOptions(
+	Converters = [typeof(SnowflakeJsonSerializer)],
+	PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
+	GenerationMode = JsonSourceGenerationMode.Default
+)]
+[JsonSerializable(typeof(ViewerJson.JsonMessage))]
+sealed partial class ViewerJsonMessageContext : JsonSerializerContext;

app/Server/Database/Export/ViewerJsonMetadataContext.cs

@@ -0,0 +1,11 @@
+using System.Text.Json.Serialization;
+
+namespace DHT.Server.Database.Export;
+
+[JsonSourceGenerationOptions(
+	Converters = [typeof(SnowflakeJsonSerializer)],
+	PropertyNamingPolicy = JsonKnownNamingPolicy.CamelCase,
+	GenerationMode = JsonSourceGenerationMode.Default
+)]
+[JsonSerializable(typeof(ViewerJson.JsonMeta))]
+sealed partial class ViewerJsonMetadataContext : JsonSerializerContext;

app/Server/Database/Export/ViewerJsonSnowflakeSerializer.cs

@@ -1,15 +0,0 @@
-using System;
-using System.Text.Json;
-using System.Text.Json.Serialization;
-
-namespace DHT.Server.Database.Export;
-
-sealed class ViewerJsonSnowflakeSerializer : JsonConverter<ulong> {
-	public override ulong Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) {
-		return ulong.Parse(reader.GetString()!);
-	}
-
-	public override void Write(Utf8JsonWriter writer, ulong value, JsonSerializerOptions options) {
-		writer.WriteStringValue(value.ToString());
-	}
-}

app/Server/Database/IDatabaseFile.cs

@@ -1,43 +1,17 @@
 using System;
-using System.Collections.Generic;
-using DHT.Server.Data;
-using DHT.Server.Data.Aggregations;
-using DHT.Server.Data.Filters;
-using DHT.Server.Download;
+using System.Threading.Tasks;
+using DHT.Server.Database.Repositories;
 
 namespace DHT.Server.Database;
 
-public interface IDatabaseFile : IDisposable {
+public interface IDatabaseFile : IAsyncDisposable {
 	string Path { get; }
-	DatabaseStatistics Statistics { get; }
-	DatabaseStatisticsSnapshot SnapshotStatistics();
 
-	void AddServer(Data.Server server);
-	List<Data.Server> GetAllServers();
+	IUserRepository Users { get; }
+	IServerRepository Servers { get; }
+	IChannelRepository Channels { get; }
+	IMessageRepository Messages { get; }
+	IDownloadRepository Downloads { get; }
 
-	void AddChannel(Channel channel);
-	List<Channel> GetAllChannels();
-
-	void AddUsers(User[] users);
-	List<User> GetAllUsers();
-
-	void AddMessages(Message[] messages);
-	int CountMessages(MessageFilter? filter = null);
-	List<Message> GetMessages(MessageFilter? filter = null);
-	HashSet<ulong> GetMessageIds(MessageFilter? filter = null);
-	void RemoveMessages(MessageFilter filter, FilterRemovalMode mode);
-
-	int CountAttachments(AttachmentFilter? filter = null);
-
-	void AddDownload(Data.Download download);
-	List<Data.Download> GetDownloadsWithoutData();
-	Data.Download GetDownloadWithData(Data.Download download);
-	DownloadedAttachment? GetDownloadedAttachment(string url);
-
-	void EnqueueDownloadItems(AttachmentFilter? filter = null);
-	List<DownloadItem> GetEnqueuedDownloadItems(int count);
-	void RemoveDownloadItems(DownloadItemFilter? filter, FilterRemovalMode mode);
-	DownloadStatusStatistics GetDownloadStatusStatistics();
-
-	void Vacuum();
+	Task Vacuum();
 }