Refactor validation and dialogs

Directory.Packages.props

@@ -2,21 +2,22 @@
   <PropertyGroup>
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
     <CentralPackageTransitivePinningEnabled>false</CentralPackageTransitivePinningEnabled>
-    <BclVersion>10.0.8</BclVersion>
-    <AvaloniaVersion>12.0.4</AvaloniaVersion>
+    <BclVersion>10.0.10</BclVersion>
+    <AvaloniaVersion>12.1.0</AvaloniaVersion>
   </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="Avalonia" Version="$(AvaloniaVersion)" />
     <PackageVersion Include="Avalonia.AvaloniaEdit" Version="12.0.0" />
-    <PackageVersion Include="Avalonia.Controls.DataGrid" Version="12.0.0" />
+    <PackageVersion Include="Avalonia.Controls.DataGrid" Version="12.1.0" />
     <PackageVersion Include="Avalonia.Desktop" Version="$(AvaloniaVersion)" />
-    <PackageVersion Include="Avalonia.Themes.Fluent" Version="$(AvaloniaVersion)" />
     <PackageVersion Include="Avalonia.Fonts.Inter" Version="$(AvaloniaVersion)" />
-    <PackageVersion Include="AvaloniaUI.DiagnosticsSupport" Version="2.2.1" />
+    <PackageVersion Include="Avalonia.Themes.Fluent" Version="$(AvaloniaVersion)" />
+    <PackageVersion Include="AvaloniaUI.DiagnosticsSupport" Version="2.2.3" />
     <PackageVersion Include="BCnEncoder.Net" Version="2.2.1" />
     <PackageVersion Include="CommunityToolkit.Mvvm" Version="8.4.2" />
     <PackageVersion Include="CommunityToolkit.Diagnostics" Version="8.4.2" />
     <PackageVersion Include="ConsoleAppFramework" Version="5.2.4" />
+    <PackageVersion Include="FluentValidation" Version="12.1.1" />
     <PackageVersion Include="K4os.Compression.LZ4" Version="1.3.8" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="$(BclVersion)" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="$(BclVersion)" />

src/EgoEngineLibrary.Frontend.Avalonia/Dialogs/AvaloniaDialogService.cs

@@ -0,0 +1,166 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Controls.ApplicationLifetimes;
+using Avalonia.Threading;
+using EgoEngineLibrary.Frontend.Dialogs.File;
+
+namespace EgoEngineLibrary.Frontend.Dialogs;
+
+/// <summary>
+/// A <see cref="IDialogService"/> for Avalonia.
+/// </summary>
+public sealed class AvaloniaDialogService : DialogServiceBase
+{
+    /// <summary>
+    /// Initializes a new instance of <see cref="AvaloniaDialogService"/>.
+    /// </summary>
+    public AvaloniaDialogService(IServiceProvider serviceProvider) : base(serviceProvider)
+    {
+    }
+
+    /// <inheritdoc />
+    public override async Task<bool?> ShowDialogAsync(IDialogViewModel viewModel)
+    {
+        if (!Dispatcher.UIThread.CheckAccess())
+        {
+            return await Dispatcher.UIThread.InvokeAsync(() => ShowDialogAsync(viewModel));
+        }
+
+        var frameworkHandled = await HandleFrameworkDialogsAsync(viewModel);
+        if (frameworkHandled)
+        {
+            // result unused
+            return false;
+        }
+
+        var window = CreateWindow(viewModel);
+        var ctx = new DialogContext(window, viewModel);
+        try
+        {
+            viewModel.DialogContext = ctx;
+            _ = await window.ShowDialog<bool>(GetOwner());
+            return await ctx.ResultTask;
+        }
+        finally
+        {
+            ctx.Close(false);
+        }
+    }
+
+    private static async Task<bool> HandleFrameworkDialogsAsync(IDialogViewModel viewModel)
+    {
+        Task? task = viewModel switch
+        {
+            FileOpenViewModel fileOpenViewModel => FileDialogAvalonia.FileOpen(GetOwner(), fileOpenViewModel),
+            FileSaveViewModel fileSaveViewModel => FileDialogAvalonia.FileSave(GetOwner(), fileSaveViewModel),
+            FolderOpenViewModel folderOpenViewModel => FileDialogAvalonia.FolderOpen(GetOwner(), folderOpenViewModel),
+            _ => null
+        };
+
+        if (task is null)
+        {
+            return false;
+        }
+
+        await task;
+        return true;
+    }
+
+    public override void Show(IDialogViewModel viewModel)
+    {
+        if (!Dispatcher.UIThread.CheckAccess())
+        {
+            Dispatcher.UIThread.Invoke(() => Show(viewModel));
+            return;
+        }
+
+        var window = CreateWindow(viewModel);
+        var ctx = new DialogContext(window, viewModel);
+        try
+        {
+            viewModel.DialogContext = ctx;
+        }
+        catch
+        {
+            ctx.Close(false);
+            throw;
+        }
+
+        window.Show(GetOwner());
+    }
+
+    private static Window CreateWindow(IDialogViewModel viewModel)
+    {
+        return new Window
+        {
+            Title = viewModel.Title,
+            CanMinimize = false,
+            CanResize = false,
+            Content = viewModel,
+            SizeToContent = SizeToContent.WidthAndHeight,
+            WindowStartupLocation = WindowStartupLocation.CenterOwner,
+        };
+    }
+
+    private static Window GetOwner()
+    {
+        if (Application.Current?.ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
+        {
+            return desktop.MainWindow ?? throw new InvalidOperationException("Main window is null.");
+        }
+
+        throw new InvalidOperationException("ApplicationLifetime not supported");
+    }
+
+    private class DialogContext : IDialogContext
+    {
+        private readonly TaskCompletionSource<bool> _resultTcs;
+        private Window? _dialogWindow;
+        private IDialogViewModel? _viewModel;
+
+        public Task<bool> ResultTask => _resultTcs.Task;
+
+        public DialogContext(Window dialogWindow, IDialogViewModel viewModel)
+        {
+            _resultTcs = new TaskCompletionSource<bool>();
+            _dialogWindow = dialogWindow;
+            _viewModel = viewModel;
+            _dialogWindow.Closed += DialogWindowOnClosed;
+        }
+
+        private void DialogWindowOnClosed(object? sender, EventArgs e)
+        {
+            _dialogWindow?.Closed -= DialogWindowOnClosed;
+            Close(false);
+        }
+
+        public void Close(bool result = true)
+        {
+            if (!_resultTcs.TrySetResult(result))
+            {
+                // Already closed
+                return;
+            }
+
+            _viewModel?.DialogContext = null;
+            _viewModel = null;
+
+            var dialogWindow = _dialogWindow;
+            _dialogWindow = null;
+            if (dialogWindow is null)
+            {
+                return;
+            }
+
+            dialogWindow.Closed -= DialogWindowOnClosed;
+            if (dialogWindow.Dispatcher.CheckAccess())
+            {
+                dialogWindow.Close();
+            }
+            else
+            {
+                dialogWindow.Dispatcher.Invoke(dialogWindow.Close);
+            }
+        }
+    }
+}