refactor: commandline parsing

* `--rebase-todo-editor` launches this app as a git `sequence.editor`
* `--rebase-message-editor` launches this app as a git `core.editor` which runs on background by reading rebasing jobs
* `--core-editor` launches this app as a git `core.editor`
* `--askpass` launches this app as a SSH askpass program

src/App.JsonCodeGen.cs

@@ -59,7 +59,7 @@ namespace SourceGit
             typeof(GridLengthConverter),
         ]
     )]
-    [JsonSerializable(typeof(List<Models.InteractiveRebaseJob>))]
+    [JsonSerializable(typeof(Models.InteractiveRebaseJobCollection))]
     [JsonSerializable(typeof(Models.JetBrainsState))]
     [JsonSerializable(typeof(Models.ThemeOverrides))]
     [JsonSerializable(typeof(Models.Version))]

src/App.axaml.cs

@@ -47,8 +47,10 @@ namespace SourceGit
         {
             try
             {
-                if (args.Length > 1 && args[0].Equals("--rebase-editor", StringComparison.Ordinal))
-                    Environment.Exit(Models.InteractiveRebaseEditor.Process(args[1]));
+                if (TryLaunchedAsRebaseTodoEditor(args, out int exitTodo))
+                    Environment.Exit(exitTodo);
+                else if (TryLaunchedAsRebaseMessageEditor(args, out int exitMessage))
+                    Environment.Exit(exitMessage);
                 else
                     BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
             }
@@ -326,28 +328,14 @@ namespace SourceGit
             {
                 BindingPlugins.DataValidators.RemoveAt(0);
 
-                var commandlines = Environment.GetCommandLineArgs();
-                if (TryParseAskpass(commandlines, out var keyname))
-                {
-                    desktop.MainWindow = new Views.Askpass(Path.GetFileName(keyname));
-                }
-                else
-                {
-                    Native.OS.SetupEnternalTools();
+                if (TryLaunchedAsCoreEditor(desktop))
+                    return;
 
-                    _launcher = new ViewModels.Launcher(commandlines);
-                    desktop.MainWindow = new Views.Launcher() { DataContext = _launcher };
+                if (TryLaunchedAsAskpass(desktop))
+                    return;
 
-                    var pref = ViewModels.Preference.Instance;
-                    if (pref.ShouldCheck4UpdateOnStartup)
-                    {
-                        pref.Save();
-                        Check4Update();
-                    }
-                }
+                TryLaunchedAsNormal(desktop);
             }
-
-            base.OnFrameworkInitializationCompleted();
         }
 
         private static void ShowSelfUpdateResult(object data)
@@ -358,10 +346,7 @@ namespace SourceGit
                 {
                     var dialog = new Views.SelfUpdate()
                     {
-                        DataContext = new ViewModels.SelfUpdate
-                        {
-                            Data = data
-                        }
+                        DataContext = new ViewModels.SelfUpdate() { Data = data }
                     };
 
                     dialog.Show(desktop.MainWindow);
@@ -369,18 +354,133 @@ namespace SourceGit
             });
         }
 
-        private static bool TryParseAskpass(string[] args, out string keyname)
+        private static bool TryLaunchedAsRebaseTodoEditor(string[] args, out int exitCode)
         {
-            keyname = string.Empty;
+            exitCode = -1;
 
-            if (args.Length != 2)
+            if (args.Length <= 1 || !args[0].Equals("--rebase-todo-editor", StringComparison.Ordinal))
+                return false;
+
+            var file = args[1];
+            var filename = Path.GetFileName(file);
+            if (!filename.Equals("git-rebase-todo", StringComparison.OrdinalIgnoreCase))
+                return true;
+
+            var dirInfo = new DirectoryInfo(Path.GetDirectoryName(file));
+            if (!dirInfo.Exists || !dirInfo.Name.Equals("rebase-merge", StringComparison.Ordinal))
+                return true;
+
+            var jobsFile = Path.Combine(dirInfo.Parent.FullName, "sourcegit_rebase_jobs.json");
+            if (!File.Exists(jobsFile))
+                return true;
+
+            var collection = JsonSerializer.Deserialize(File.ReadAllText(jobsFile), JsonCodeGen.Default.InteractiveRebaseJobCollection);
+            var lines = new List<string>();
+            foreach (var job in collection.Jobs)
+            {
+                switch (job.Action)
+                {
+                    case Models.InteractiveRebaseAction.Pick:
+                        lines.Add($"p {job.SHA}");
+                        break;
+                    case Models.InteractiveRebaseAction.Edit:
+                        lines.Add($"e {job.SHA}");
+                        break;
+                    case Models.InteractiveRebaseAction.Reword:
+                        lines.Add($"r {job.SHA}");
+                        break;
+                    case Models.InteractiveRebaseAction.Squash:
+                        lines.Add($"s {job.SHA}");
+                        break;
+                    case Models.InteractiveRebaseAction.Fixup:
+                        lines.Add($"f {job.SHA}");
+                        break;
+                    default:
+                        lines.Add($"d {job.SHA}");
+                        break;
+                }
+            }
+
+            File.WriteAllLines(file, lines);
+
+            exitCode = 0;
+            return true;
+        }
+
+        private static bool TryLaunchedAsRebaseMessageEditor(string[] args, out int exitCode)
+        {
+            exitCode = -1;
+
+            if (args.Length <= 1 || !args[0].Equals("--rebase-message-editor", StringComparison.Ordinal))
+                return false;
+
+            var file = args[1];
+            var filename = Path.GetFileName(file);
+            if (!filename.Equals("COMMIT_EDITMSG", StringComparison.OrdinalIgnoreCase))
+                return true;
+
+            var jobsFile = Path.Combine(Path.GetDirectoryName(file), "sourcegit_rebase_jobs.json");
+            if (!File.Exists(jobsFile))
+                return true;
+
+            var collection = JsonSerializer.Deserialize(File.ReadAllText(jobsFile), JsonCodeGen.Default.InteractiveRebaseJobCollection);
+            var doneFile = Path.Combine(Path.GetDirectoryName(file), "rebase-merge", "done");
+            if (!File.Exists(doneFile))
+                return true;
+
+            var done = File.ReadAllText(doneFile).Split(new char[] { '\n', '\r' }, StringSplitOptions.RemoveEmptyEntries);
+            if (done.Length > collection.Jobs.Count)
+                return true;
+
+            var job = collection.Jobs[done.Length - 1];
+            File.WriteAllText(file, job.Message);
+
+            exitCode = 0;
+            return true;
+        }
+
+        private bool TryLaunchedAsCoreEditor(IClassicDesktopStyleApplicationLifetime desktop)
+        {
+            var args = desktop.Args;
+            if (args.Length <= 1 || !args[0].Equals("--core-editor", StringComparison.Ordinal))
+                return false;
+
+            var file = args[1];
+            if (!File.Exists(file))
+                Environment.Exit(-1);
+
+            desktop.MainWindow = new Views.CodeEditor(file);
+            return true;
+        }
+
+        private bool TryLaunchedAsAskpass(IClassicDesktopStyleApplicationLifetime desktop)
+        {
+            var args = desktop.Args;
+            if (args.Length <= 1 || !args[0].Equals("--askpass", StringComparison.Ordinal))
                 return false;
 
             var match = REG_ASKPASS().Match(args[1]);
-            if (match.Success)
-                keyname = match.Groups[1].Value;
+            if (!match.Success)
+                return false;
+                
+            desktop.MainWindow = new Views.Askpass(Path.GetFileName(match.Groups[1].Value));
+            return true;
+        }
 
-            return match.Success;
+        private void TryLaunchedAsNormal(IClassicDesktopStyleApplicationLifetime desktop)
+        {
+            Native.OS.SetupEnternalTools();
+
+            var startupRepo = desktop.Args.Length == 1 && Directory.Exists(desktop.Args[0]) ? desktop.Args[0] : null;
+            _launcher = new ViewModels.Launcher(startupRepo);
+            desktop.MainWindow = new Views.Launcher() { DataContext = _launcher };
+
+            var pref = ViewModels.Preference.Instance;
+            if (pref.ShouldCheck4UpdateOnStartup)
+            {
+                pref.Save();
+                Check4Update();
+            }
         }
 
         [GeneratedRegex(@"Enter\s+passphrase\s*for\s*key\s*['""]([^'""]+)['""]\:\s*", RegexOptions.IgnoreCase)]

src/Commands/Command.cs

@@ -3,7 +3,6 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.Text;
 using System.Text.RegularExpressions;
-
 using Avalonia.Threading;
 
 namespace SourceGit.Commands
@@ -22,9 +21,17 @@ namespace SourceGit.Commands
             public string StdErr { get; set; }
         }
 
+        public enum EditorType
+        {
+            None,
+            CoreEditor,
+            RebaseEditor,
+        }
+
         public string Context { get; set; } = string.Empty;
         public CancelToken Cancel { get; set; } = null;
         public string WorkingDirectory { get; set; } = null;
+        public EditorType Editor { get; set; } = EditorType.CoreEditor; // Only used in Exec() mode
         public string Args { get; set; } = string.Empty;
         public bool RaiseError { get; set; } = true;
         public bool TraitErrorAsOutput { get; set; } = false;
@@ -33,7 +40,7 @@ namespace SourceGit.Commands
         public void UseSSHKey(string key)
         {
             Envs.Add("DISPLAY", "required");
-            Envs.Add("SSH_ASKPASS", Process.GetCurrentProcess().MainModule.FileName);
+            Envs.Add("SSH_ASKPASS", $"\"{Process.GetCurrentProcess().MainModule.FileName}\" --askpass");
             Envs.Add("SSH_ASKPASS_REQUIRE", "prefer");
             Envs.Add("GIT_SSH_COMMAND", $"ssh -i '{key}'");
         }
@@ -42,7 +49,7 @@ namespace SourceGit.Commands
         {
             var start = new ProcessStartInfo();
             start.FileName = Native.OS.GitExecutable;
-            start.Arguments = "--no-pager -c core.quotepath=off " + Args;
+            start.Arguments = "--no-pager -c core.quotepath=off ";
             start.UseShellExecute = false;
             start.CreateNoWindow = true;
             start.RedirectStandardOutput = true;
@@ -50,6 +57,24 @@ namespace SourceGit.Commands
             start.StandardOutputEncoding = Encoding.UTF8;
             start.StandardErrorEncoding = Encoding.UTF8;
 
+            // Editors
+            var editorProgram = $"\\\"{Process.GetCurrentProcess().MainModule.FileName}\\\"";
+            switch (Editor)
+            {
+                case EditorType.CoreEditor:
+                    start.Arguments += $"-c core.editor=\"{editorProgram} --core-editor\" ";
+                    break;
+                case EditorType.RebaseEditor:
+                    start.Arguments += $"-c core.editor=\"{editorProgram} --rebase-message-editor\" -c sequence.editor=\"{editorProgram} --rebase-todo-editor\" -c rebase.abbreviateCommands=true ";
+                    break;
+                default:
+                    start.Arguments += "-c core.editor=true ";
+                    break;
+            }
+
+            // Append command args
+            start.Arguments += Args;
+
             // User environment overrides.
             foreach (var kv in Envs)
                 start.Environment.Add(kv.Key, kv.Value);

src/Commands/Rebase.cs

@@ -1,6 +1,4 @@
-using System.Diagnostics;
-
-namespace SourceGit.Commands
+namespace SourceGit.Commands
 {
     public class Rebase : Command
     {
@@ -19,12 +17,10 @@ namespace SourceGit.Commands
     {
         public InteractiveRebase(string repo, string basedOn)
         {
-            var exec = Process.GetCurrentProcess().MainModule.FileName;
-            var editor = $"\\\"{exec}\\\" --rebase-editor";
-
             WorkingDirectory = repo;
             Context = repo;
-            Args = $"-c core.editor=\"{editor}\" -c sequence.editor=\"{editor}\" -c rebase.abbreviateCommands=true rebase -i --autosquash {basedOn}";
+            Editor = EditorType.RebaseEditor;
+            Args = $"rebase -i --autosquash {basedOn}";
         }
     }
 }

src/Models/InteractiveRebase.cs

@@ -0,0 +1,26 @@
+using System.Collections.Generic;
+
+namespace SourceGit.Models
+{
+    public enum InteractiveRebaseAction
+    {
+        Pick,
+        Edit,
+        Reword,
+        Squash,
+        Fixup,
+        Drop,
+    }
+
+    public class InteractiveRebaseJob
+    {
+        public string SHA { get; set; } = string.Empty;
+        public InteractiveRebaseAction Action { get; set; } = InteractiveRebaseAction.Pick;
+        public string Message { get; set; } = string.Empty;
+    }
+
+    public class InteractiveRebaseJobCollection
+    {
+        public List<InteractiveRebaseJob> Jobs { get; set; } = new List<InteractiveRebaseJob>();
+    }
+}

src/Models/InteractiveRebaseEditor.cs

@@ -1,98 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
-using System.Text.Json;
-
-namespace SourceGit.Models
-{
-    public enum InteractiveRebaseAction
-    {
-        Pick,
-        Edit,
-        Reword,
-        Squash,
-        Fixup,
-        Drop,
-    }
-
-    public class InteractiveRebaseJob
-    {
-        public string SHA { get; set; } = string.Empty;
-        public InteractiveRebaseAction Action { get; set; } = InteractiveRebaseAction.Pick;
-        public string Message { get; set; } = string.Empty;
-    }
-
-    public static class InteractiveRebaseEditor
-    {
-        public static int Process(string file)
-        {
-            try
-            {
-                var filename = Path.GetFileName(file);
-                if (filename.Equals("git-rebase-todo", StringComparison.OrdinalIgnoreCase))
-                {
-                    var dirInfo = new DirectoryInfo(Path.GetDirectoryName(file));
-                    if (!dirInfo.Exists || !dirInfo.Name.Equals("rebase-merge", StringComparison.Ordinal))
-                        return -1;
-
-                    var jobsFile = Path.Combine(dirInfo.Parent.FullName, "sourcegit_rebase_jobs.json");
-                    if (!File.Exists(jobsFile))
-                        return -1;
-
-                    var jobs = JsonSerializer.Deserialize(File.ReadAllText(jobsFile), JsonCodeGen.Default.ListInteractiveRebaseJob);
-                    var lines = new List<string>();
-                    foreach (var job in jobs)
-                    {
-                        switch (job.Action)
-                        {
-                            case InteractiveRebaseAction.Pick:
-                                lines.Add($"p {job.SHA}");
-                                break;
-                            case InteractiveRebaseAction.Edit:
-                                lines.Add($"e {job.SHA}");
-                                break;
-                            case InteractiveRebaseAction.Reword:
-                                lines.Add($"r {job.SHA}");
-                                break;
-                            case InteractiveRebaseAction.Squash:
-                                lines.Add($"s {job.SHA}");
-                                break;
-                            case InteractiveRebaseAction.Fixup:
-                                lines.Add($"f {job.SHA}");
-                                break;
-                            default:
-                                lines.Add($"d {job.SHA}");
-                                break;
-                        }
-                    }
-
-                    File.WriteAllLines(file, lines);
-                } 
-                else if (filename.Equals("COMMIT_EDITMSG", StringComparison.OrdinalIgnoreCase))
-                {
-                    var jobsFile = Path.Combine(Path.GetDirectoryName(file), "sourcegit_rebase_jobs.json");
-                    if (!File.Exists(jobsFile))
-                        return 0;
-
-                    var jobs = JsonSerializer.Deserialize(File.ReadAllText(jobsFile), JsonCodeGen.Default.ListInteractiveRebaseJob);
-                    var doneFile = Path.Combine(Path.GetDirectoryName(file), "rebase-merge", "done");
-                    if (!File.Exists(doneFile))
-                        return -1;
-
-                    var done = File.ReadAllText(doneFile).Split(new char[] {'\n', '\r'}, StringSplitOptions.RemoveEmptyEntries);
-                    if (done.Length > jobs.Count)
-                        return -1;
-
-                    var job = jobs[done.Length - 1];
-                    File.WriteAllText(file, job.Message);
-                }
-
-                return 0;
-            }
-            catch
-            {
-                return -1;
-            }
-        }
-    }
-}

src/Resources/Locales/en_US.axaml

@@ -91,6 +91,7 @@
   <x:String x:Key="Text.Clone.ParentFolder" xml:space="preserve">Parent Folder:</x:String>
   <x:String x:Key="Text.Clone.RemoteURL" xml:space="preserve">Repository URL:</x:String>
   <x:String x:Key="Text.Close" xml:space="preserve">CLOSE</x:String>
+  <x:String x:Key="Text.CodeEditor" xml:space="preserve">Editor</x:String>
   <x:String x:Key="Text.CommitCM.CherryPick" xml:space="preserve">Cherry-Pick This Commit</x:String>
   <x:String x:Key="Text.CommitCM.Checkout" xml:space="preserve">Checkout Commit</x:String>
   <x:String x:Key="Text.CommitCM.CompareWithHead" xml:space="preserve">Compare with HEAD</x:String>

src/Resources/Locales/zh_CN.axaml

@@ -94,6 +94,7 @@
   <x:String x:Key="Text.Clone.ParentFolder" xml:space="preserve">父级目录 ：</x:String>
   <x:String x:Key="Text.Clone.RemoteURL" xml:space="preserve">远程仓库 ：</x:String>
   <x:String x:Key="Text.Close" xml:space="preserve">关闭</x:String>
+  <x:String x:Key="Text.CodeEditor" xml:space="preserve">提交信息编辑器</x:String>
   <x:String x:Key="Text.CommitCM.CherryPick" xml:space="preserve">挑选(cherry-pick)此提交</x:String>
   <x:String x:Key="Text.CommitCM.Checkout" xml:space="preserve">检出此提交</x:String>
   <x:String x:Key="Text.CommitCM.CompareWithHead" xml:space="preserve">与当前HEAD比较</x:String>

src/Resources/Locales/zh_TW.axaml

@@ -94,6 +94,7 @@
   <x:String x:Key="Text.Clone.ParentFolder" xml:space="preserve">父級目錄 ：</x:String>
   <x:String x:Key="Text.Clone.RemoteURL" xml:space="preserve">遠端倉庫 ：</x:String>
   <x:String x:Key="Text.Close" xml:space="preserve">關閉</x:String>
+  <x:String x:Key="Text.CodeEditor" xml:space="preserve">提交資訊編輯器</x:String>
   <x:String x:Key="Text.CommitCM.CherryPick" xml:space="preserve">挑選(cherry-pick)此提交</x:String>
   <x:String x:Key="Text.CommitCM.Checkout" xml:space="preserve">檢出此提交</x:String>
   <x:String x:Key="Text.CommitCM.CompareWithHead" xml:space="preserve">與當前HEAD比較</x:String>

src/ViewModels/InProgressContexts.cs

@@ -1,5 +1,4 @@
-using System.Diagnostics;
-using System.IO;
+using System.IO;
 
 namespace SourceGit.ViewModels
 {
@@ -39,7 +38,8 @@ namespace SourceGit.ViewModels
             {
                 WorkingDirectory = Repository,
                 Context = Repository,
-                Args = $"-c core.editor=true {Cmd} --continue",
+                Editor = Commands.Command.EditorType.None,
+                Args = $"{Cmd} --continue",
             }.Exec();
         }
     }
@@ -58,14 +58,12 @@ namespace SourceGit.ViewModels
 
         public override bool Continue()
         {
-            var exec = Process.GetCurrentProcess().MainModule.FileName;
-            var editor = $"\\\"{exec}\\\" --rebase-editor";
-
             var succ = new Commands.Command()
             {
                 WorkingDirectory = Repository,
                 Context = Repository,
-                Args = $"-c core.editor=\"{editor}\" rebase --continue",
+                Editor = Commands.Command.EditorType.RebaseEditor,
+                Args = $"rebase --continue",
             }.Exec();
 
             if (succ)

src/ViewModels/InteractiveRebase.cs

@@ -168,18 +168,18 @@ namespace SourceGit.ViewModels
             _repo.SetWatcherEnabled(false);
 
             var saveFile = Path.Combine(_repo.GitDir, "sourcegit_rebase_jobs.json");
-            var jobs = new List<Models.InteractiveRebaseJob>();
+            var collection = new Models.InteractiveRebaseJobCollection();
             for (int i = Items.Count - 1; i >= 0; i--)
             {
                 var item = Items[i];
-                jobs.Add(new Models.InteractiveRebaseJob()
+                collection.Jobs.Add(new Models.InteractiveRebaseJob()
                 {
                     SHA = item.Commit.SHA,
                     Action = item.Action,
                     Message = item.FullMessage,
                 });
             }
-            File.WriteAllText(saveFile, JsonSerializer.Serialize(jobs, JsonCodeGen.Default.ListInteractiveRebaseJob));
+            File.WriteAllText(saveFile, JsonSerializer.Serialize(collection, JsonCodeGen.Default.InteractiveRebaseJobCollection));
 
             return Task.Run(() =>
             {

src/ViewModels/Launcher.cs

@@ -28,21 +28,20 @@ namespace SourceGit.ViewModels
             }
         }
 
-        public Launcher(string[] commandlines)
+        public Launcher(string startupRepo)
         {
             Pages = new AvaloniaList<LauncherPage>();
             AddNewTab();
             
-            if (commandlines.Length == 2)
+            if (!string.IsNullOrEmpty(startupRepo))
             {
-                var path = commandlines[1];
-                var root = new Commands.QueryRepositoryRootPath(path).Result();
+                var root = new Commands.QueryRepositoryRootPath(startupRepo).Result();
                 if (string.IsNullOrEmpty(root))
                 {
                     Pages[0].Notifications.Add(new Notification
                     {
                         IsError = true,
-                        Message = $"Given path: '{path}' is NOT a valid repository!"
+                        Message = $"Given path: '{startupRepo}' is NOT a valid repository!"
                     });
                     return;
                 }

src/Views/CodeEditor.axaml

@@ -0,0 +1,62 @@
+<v:ChromelessWindow xmlns="https://github.com/avaloniaui"
+                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+                    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+                    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+                    xmlns:vm="using:SourceGit.ViewModels"
+                    xmlns:v="using:SourceGit.Views"
+                    mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
+                    x:Class="SourceGit.Views.CodeEditor"
+                    Icon="/App.ico"
+                    Title="{DynamicResource Text.CodeEditor}"
+                    Width="800"
+                    SizeToContent="Height"
+                    CanResize="False"
+                    WindowStartupLocation="CenterScreen">
+  <Grid RowDefinitions="Auto,*">
+    <!-- TitleBar -->
+    <Grid Grid.Row="0" ColumnDefinitions="Auto,*,Auto" Height="30">
+      <Border Grid.Column="0" Grid.ColumnSpan="3"
+              Background="{DynamicResource Brush.TitleBar}"
+              BorderThickness="0,0,0,1" BorderBrush="{DynamicResource Brush.Border0}"
+              PointerPressed="BeginMoveWindow"/>
+
+      <Path Grid.Column="0"
+            Width="14" Height="14"
+            Margin="10,0,0,0"
+            Data="{StaticResource Icons.Edit}"
+            IsVisible="{OnPlatform True, macOS=False}"/>
+
+      <Grid Grid.Column="0" Classes="caption_button_box" Margin="2,4,0,0" IsVisible="{OnPlatform False, macOS=True}">
+        <Button Classes="caption_button_macos" Click="CloseWindow">
+          <Grid>
+            <Ellipse Fill="{DynamicResource Brush.MacOS.Close}"/>
+            <Path Height="6" Width="6" Stretch="Fill" Fill="#404040" Stroke="#404040" StrokeThickness="1" Data="{StaticResource Icons.Window.Close}"/>
+          </Grid>
+        </Button>
+      </Grid>
+
+      <TextBlock Grid.Column="0" Grid.ColumnSpan="3"
+                 Classes="bold"
+                 Text="{DynamicResource Text.CodeEditor}"
+                 HorizontalAlignment="Center" VerticalAlignment="Center"
+                 IsHitTestVisible="False"/>
+
+      <Button Grid.Column="2"
+              Classes="caption_button"
+              Click="CloseWindow"
+              IsVisible="{OnPlatform True, macOS=False}">
+        <Path Data="{StaticResource Icons.Window.Close}"/>
+      </Button>
+    </Grid>
+
+    <StackPanel Grid.Row="1" Orientation="Vertical" Margin="8">
+      <v:CommitMessageTextBox x:Name="Editor" Height="400" Text=""/>
+      <Button Classes="flat primary"
+              Width="80"
+              Margin="0,8,0,4"
+              Content="{DynamicResource Text.Sure}"
+              Click="SaveAndClose"
+              HorizontalAlignment="Center"/>
+    </StackPanel>
+  </Grid>
+</v:ChromelessWindow>

src/Views/CodeEditor.axaml.cs

@@ -0,0 +1,54 @@
+using System;
+using System.IO;
+using System.Text;
+using Avalonia.Input;
+using Avalonia.Interactivity;
+
+namespace SourceGit.Views
+{
+    public partial class CodeEditor : ChromelessWindow
+    {
+        public CodeEditor()
+        {
+            DataContext = this;
+            InitializeComponent();
+        }
+
+        public CodeEditor(string file)
+        {
+            _file = file;
+            DataContext = this;
+            InitializeComponent();
+
+            var content = File.ReadAllText(file).ReplaceLineEndings("\n");
+            var firstLineEnd = content.IndexOf('\n');
+            if (firstLineEnd == -1)
+            {
+                Editor.SubjectEditor.Text = content;
+            }
+            else
+            {
+                Editor.SubjectEditor.Text = content.Substring(0, firstLineEnd);
+                Editor.DescriptionEditor.Text = content.Substring(firstLineEnd + 1);
+            }
+        }
+
+        private void BeginMoveWindow(object sender, PointerPressedEventArgs e)
+        {
+            BeginMoveDrag(e);
+        }
+
+        private void CloseWindow(object sender, RoutedEventArgs e)
+        {
+            Environment.Exit(-1);
+        }
+
+        private void SaveAndClose(object sender, RoutedEventArgs e)
+        {
+            File.WriteAllText(_file, Editor.Text);
+            Environment.Exit(0);
+        }
+
+        private string _file = string.Empty;
+    }
+}