feat: use TasFile model to replace some view model code.

BallanceTasEditor/BallanceTasEditor/BallanceTasEditor.csproj

@@ -15,13 +15,9 @@
 
   <ItemGroup>
     <PackageReference Include="CommunityToolkit.HighPerformance" Version="8.4.0" />
-    <PackageReference Include="CommunityToolkit.Mvvm" Version="8.2.1" />
+    <PackageReference Include="CommunityToolkit.Mvvm" Version="8.4.2" />
     <PackageReference Include="OneOf" Version="3.0.271" />
     <PackageReference Include="System.Configuration.ConfigurationManager" Version="10.0.5" />
   </ItemGroup>
 
-  <ItemGroup>
-    <Folder Include="Frontend\Models\" />
-  </ItemGroup>
-
 </Project>

BallanceTasEditor/BallanceTasEditor/Frontend/Models/TasFile.cs

@@ -0,0 +1,84 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace BallanceTasEditor.Frontend.Models {
+    public partial class TasFile : ObservableObject {
+        public TasFile() {
+            FileBody = null;
+        }
+
+        #region File Load and Save
+
+        [ObservableProperty]
+        [NotifyPropertyChangedFor(nameof(IsFileLoaded))]
+        [NotifyPropertyChangedFor(nameof(IsFileNotLoaded))]
+        private Backend.ITasSequence? fileBody;
+
+        [MemberNotNullWhen(true, nameof(FileBody))]
+        public bool IsFileLoaded {
+            get => FileBody is not null;
+        }
+
+        [MemberNotNullWhen(false, nameof(FileBody))]
+        public bool IsFileNotLoaded {
+            get => FileBody is null;
+        }
+
+        public void NewFile(TasSequenceKind kind, int count, uint fps) {
+            // Check status
+            if (IsFileLoaded) {
+                throw new InvalidOperationException();
+            }
+
+            // Initialize sequence
+            var seq = TasSequenceKindHelper.CreateSequenceByKind(kind);
+            // Initialize items
+            Backend.TasStorage.Init(seq, count, fps);
+            // Set members
+            FileBody = seq;
+        }
+
+        public void LoadFile(TasSequenceKind kind, string path) {
+            // Check status
+            if (IsFileLoaded) {
+                throw new InvalidOperationException();
+            }
+
+            // Initialize sequence
+            var seq = TasSequenceKindHelper.CreateSequenceByKind(kind);
+            // Load into sequence
+            Backend.TasStorage.Load(path, seq);
+            // Set members
+            FileBody = seq;
+        }
+
+        public void SaveFile(string path) {
+            // Check status
+            if (IsFileNotLoaded) {
+                throw new InvalidOperationException();
+            }
+
+            // Save sequence
+            Backend.TasStorage.Save(path, FileBody);
+        }
+
+        public void CloseFile() {
+            // Check status
+            if (IsFileNotLoaded) {
+                throw new InvalidOperationException();
+            }
+
+            // Set member
+            FileBody = null;
+        }
+
+        #endregion
+
+    }
+}

BallanceTasEditor/BallanceTasEditor/Frontend/Models/TasSequenceKind.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+
+namespace BallanceTasEditor.Frontend.Models {
+    public enum TasSequenceKind {
+        Array,
+        DoubleLinkedList
+    }
+
+    public static class  TasSequenceKindHelper {
+        public static Backend.ITasSequence CreateSequenceByKind(TasSequenceKind kind) {
+            return kind switch {
+                TasSequenceKind.Array => new Backend.ListTasSequence(),
+                TasSequenceKind.DoubleLinkedList => new Backend.LegacyTasSequence(),
+                _ => throw new UnreachableException(),
+            };
+        }
+    }
+
+}

BallanceTasEditor/BallanceTasEditor/Frontend/ViewModels/MainWindow.cs

@@ -15,8 +15,9 @@ namespace BallanceTasEditor.Frontend.ViewModels {
         public MainWindow(Shared.IDialogService dialogService) {
             m_DialogService = dialogService;
 
-            this.TasFile = null;
+            TasFile = new Models.TasFile();
-            this.TasFilePath = null;
+            TasFile.PropertyChanged += TasFile_PropertyChanged;
+            TasFilePath = null;
 
             this.StatusMessage = "";
             m_StatusMessageDimmer = new DispatcherTimer();
@@ -33,34 +34,38 @@ namespace BallanceTasEditor.Frontend.ViewModels {
 
         [ObservableProperty]
         [NotifyPropertyChangedFor(nameof(WindowTitle))]
-        [NotifyCanExecuteChangedFor(nameof(NewFileCommand))]
+        private Models.TasFile tasFile;
-        [NotifyCanExecuteChangedFor(nameof(OpenFileCommand))]
-        [NotifyCanExecuteChangedFor(nameof(SaveFileCommand))]
-        [NotifyCanExecuteChangedFor(nameof(SaveFileAsCommand))]
-        [NotifyCanExecuteChangedFor(nameof(CloseFileCommand))]
-        private Backend.ITasSequence? tasFile;
         [ObservableProperty]
         [NotifyPropertyChangedFor(nameof(WindowTitle))]
         private string? tasFilePath;
 
+        private void TasFile_PropertyChanged(object? sender, System.ComponentModel.PropertyChangedEventArgs e) {
+            // YYC MARK:
+            // Due to the shitty limit of MVVM Toolkit,
+            // I was forced trigger these command manually.
+            NewFileCommand.NotifyCanExecuteChanged();
+            OpenFileCommand.NotifyCanExecuteChanged();
+            SaveFileCommand.NotifyCanExecuteChanged();
+            SaveFileAsCommand.NotifyCanExecuteChanged();
+            CloseFileCommand.NotifyCanExecuteChanged();
+        }
+
         [RelayCommand(CanExecute = nameof(CanNewFile))]
         private void NewFile() {
             // Request new file properties
             var dialog = m_DialogService.ShowNewFileDialog();
             if (dialog is null) return;
 
-            // Initialize sequence
+            // Create new file
-            var seq = new Backend.ListTasSequence();
+            TasFile.NewFile(Models.TasSequenceKind.Array, dialog.Count, dialog.Fps);
-            // Initialize items
-            Backend.TasStorage.Init(seq, dialog.Count, dialog.Fps);
             // Set members
-            this.TasFile = seq;
+            TasFilePath = null;
-            this.TasFilePath = null;
+            // Send notification
             UpdateStatusMessage($"New TAS file is created.");
         }
 
         private bool CanNewFile() {
-            return this.TasFile is null;
+            return TasFile.IsFileNotLoaded;
         }
 
         [RelayCommand(CanExecute = nameof(CanOpenFile))]
@@ -69,23 +74,21 @@ namespace BallanceTasEditor.Frontend.ViewModels {
             var dialog = m_DialogService.ShowOpenFileDialog();
             if (dialog is null) return;
 
-            // Initialize sequence
+            // Load file
-            var seq = new Backend.ListTasSequence();
-            // Load into sequence
             try {
-                Backend.TasStorage.Load(dialog.Path, seq);
+                TasFile.LoadFile(Models.TasSequenceKind.Array, dialog.Path);
             } catch (Exception e) {
                 m_DialogService.ShowOpenFileFailedDialog(e);
                 return;
             }
             // Set members
-            this.TasFile = seq;
+            TasFilePath = dialog.Path;
-            this.TasFilePath = dialog.Path;
+            // Send notification
             UpdateStatusMessage($"TAS file {this.TasFilePath} is loaded.");
         }
 
         private bool CanOpenFile() {
-            return this.TasFile is null;
+            return TasFile.IsFileNotLoaded;
         }
 
         [RelayCommand(CanExecute = nameof(CanSaveFile))]
@@ -102,18 +105,19 @@ namespace BallanceTasEditor.Frontend.ViewModels {
 
             // Save file
             try {
-                Backend.TasStorage.Save(filePath, this.TasFile.Unwrap());
+                TasFile.SaveFile(filePath);
             } catch (Exception e) {
                 m_DialogService.ShowSaveFileFailedDialog(e);
                 return;
             }
             // Update member
-            this.TasFilePath = filePath;
+            TasFilePath = filePath;
+            // Send notification
             UpdateStatusMessage($"TAS file {this.TasFilePath} is saved.");
         }
 
         private bool CanSaveFile() {
-            return this.TasFile is not null;
+            return TasFile.IsFileLoaded;
         }
 
         [RelayCommand(CanExecute = nameof(CanSaveFileAs))]
@@ -124,29 +128,33 @@ namespace BallanceTasEditor.Frontend.ViewModels {
 
             // Save file
             try {
-                Backend.TasStorage.Save(dialog.Path, this.TasFile.Unwrap());
+                TasFile.SaveFile(dialog.Path);
             } catch (Exception e) {
                 m_DialogService.ShowSaveFileFailedDialog(e);
                 return;
             }
             // Set file path
             TasFilePath = dialog.Path;
+            // Send notification
             UpdateStatusMessage($"TAS file {this.TasFilePath} is saved.");
         }
         
         private bool CanSaveFileAs() {
-            return this.TasFile is not null;
+            return TasFile.IsFileLoaded;
         }
 
         [RelayCommand(CanExecute = nameof(CanCloseFile))]
         private void CloseFile() {
-            this.TasFile = null;
+            // Close file
-            this.TasFilePath = null;
+            TasFile.CloseFile();
+            // Set members
+            TasFilePath = null;
+            // Send notification
             UpdateStatusMessage($"TAS file is closed.");
         }
 
         private bool CanCloseFile() {
-            return this.TasFile is not null;
+            return TasFile.IsFileLoaded;
         }
 
         #endregion
@@ -228,7 +236,7 @@ namespace BallanceTasEditor.Frontend.ViewModels {
 
         public string WindowTitle {
             get {
-                if (TasFile is null) {
+                if (TasFile.IsFileNotLoaded) {
                     return "Ballance TAS Editor";
                 } else {
                     if (TasFilePath is null) {