Add settings page for using legacy PDF mode

src/ViewModels/SettingsViewModel.cs

@@ -0,0 +1,58 @@
+#nullable enable
+
+using System;
+using System.Collections.ObjectModel;
+using System.Globalization;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using Avalonia.Platform.Storage;
+using Avalonia.Themes.Fluent;
+using DialogHostAvalonia;
+using ImageMagick;
+using MigraDoc.DocumentObjectModel;
+using MigraDoc.Rendering;
+using PdfSharp.Fonts;
+using PdfSharp.Pdf.IO;
+using PdfSharp.Snippets.Font;
+using MayShow.Interfaces;
+using MayShow.Models;
+using MayShow.Helpers;
+
+namespace MayShow.ViewModels;
+
+class SettingsViewModel: ChangeNotifier
+{
+    private Settings _previousSettings;
+    private Settings _settings;
+
+    public SettingsViewModel(Settings settingsToEdit)
+    {
+        _previousSettings = settingsToEdit;
+        _settings = new Settings
+        {
+            LastUsedPath = _previousSettings.LastUsedPath,
+            UseDocnetPFDImageRendering = _previousSettings.UseDocnetPFDImageRendering
+        };
+    }
+
+    public bool UseDocnetPDFImageRendering
+    {
+        get => _settings.UseDocnetPFDImageRendering;
+        set
+        {
+            _settings.UseDocnetPFDImageRendering = value;
+            NotifyPropertyChanged();
+        }
+    }
+
+    public void Cancel()
+    {
+        DialogHost.Close("DialogHost", null);
+    }
+
+    public void Save()
+    {
+        DialogHost.Close("DialogHost", _settings);
+    }
+}