feat: implement IPC for opening repositories in new tabs (#1185)

* refactor: improve diff handling for EOL changes and enhance text diff display

- Updated `Diff.cs` to streamline whitespace handling in diff arguments.
- Enhanced `DiffContext.cs` to check for EOL changes when old and new hashes differ, creating a text diff if necessary.
- Added support for showing end-of-line symbols in `TextDiffView.axaml.cs` options.

* localization: update translations to include EOF handling in ignore whitespace messages

- Modified the ignore whitespace text in multiple language files to specify that EOF changes are also ignored.
- Ensured consistency across all localization files for the patch application feature.

* revert: Typo in DiffResult comment

* revert: update diff arguments to ignore CR at EOL in whitespace handling (like before changes)

* revert: update translations to remove EOF references in Text.Apply.IgnoreWS and fixed typo in Text.Diff.IgnoreWhitespace (EOF => EOL)

* feat: add workspace-specific default clone directory functionality

- Implemented logic in Clone.cs to set ParentFolder based on the active workspace's DefaultCloneDir if available, falling back to the global GitDefaultCloneDir.
- Added DefaultCloneDir property to Workspace.cs to store the default clone directory for each workspace.
- Updated ConfigureWorkspace.axaml to include a TextBox and Button for setting the DefaultCloneDir in the UI.
- Implemented folder selection functionality in ConfigureWorkspace.axaml.cs to allow users to choose a directory for cloning.
- This closes issue #1145

* feat: implement IPC for opening repositories in new tabs

- Added functionality to send repository paths to an existing instance of the application using named pipes.
- Introduced a new preference option to open repositories in a new tab instead of a new window.
- Updated UI to include a checkbox for the new preference.
- Enhanced the handling of IPC server lifecycle based on the new preference setting.
- This closes issue #1184

---------

Co-authored-by: mpagani <massimo.pagani@unitec-group.com>

src/App.axaml.cs

@@ -2,12 +2,14 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using System.IO.Pipes;
 using System.Net.Http;
 using System.Reflection;
 using System.Text;
 using System.Text.Json;
 using System.Threading;
 using System.Threading.Tasks;
+using System.Linq;
 
 using Avalonia;
 using Avalonia.Controls;
@@ -46,6 +48,8 @@ namespace SourceGit
                     Environment.Exit(exitTodo);
                 else if (TryLaunchAsRebaseMessageEditor(args, out int exitMessage))
                     Environment.Exit(exitMessage);
+                else if (TrySendArgsToExistingInstance(args))
+                    Environment.Exit(0);
                 else
                     BuildAvaloniaApp().StartWithClassicDesktopLifetime(args);
             }
@@ -77,6 +81,44 @@ namespace SourceGit
             return builder;
         }
 
+        private static bool TrySendArgsToExistingInstance(string[] args)
+        {
+            if (args == null || args.Length != 1 || !Directory.Exists(args[0]))
+                return false;
+
+            var pref = ViewModels.Preferences.Instance;
+
+            if (!pref.OpenReposInNewTab)
+                return false;
+
+            try
+            {
+                var processes = Process.GetProcessesByName("SourceGit");
+
+                if (processes.Length <= 1)
+                    return false;
+
+                using var client = new NamedPipeClientStream(".", "SourceGitIPC", PipeDirection.Out);
+
+                client.Connect(1000);
+
+                if (client.IsConnected)
+                {
+                    using var writer = new StreamWriter(client);
+
+                    writer.WriteLine(args[0]);
+                    writer.Flush();
+
+                    return true;
+                }
+            }
+            catch (Exception)
+            {
+            }
+
+            return false;
+        }
+
         private static void LogException(Exception ex)
         {
             if (ex == null)
@@ -328,7 +370,13 @@ namespace SourceGit
             AvaloniaXamlLoader.Load(this);
 
             var pref = ViewModels.Preferences.Instance;
-            pref.PropertyChanged += (_, _) => pref.Save();
+
+            pref.PropertyChanged += (s, e) => {
+                pref.Save();
+                
+                if (e.PropertyName.Equals(nameof(ViewModels.Preferences.OpenReposInNewTab)))
+                    HandleOpenReposInNewTabChanged();
+            };
 
             SetLocale(pref.Locale);
             SetTheme(pref.Theme, pref.ThemeOverrides);
@@ -488,13 +536,104 @@ namespace SourceGit
             _launcher = new ViewModels.Launcher(startupRepo);
             desktop.MainWindow = new Views.Launcher() { DataContext = _launcher };
 
-#if !DISABLE_UPDATE_DETECTION
             var pref = ViewModels.Preferences.Instance;
+
+            HandleOpenReposInNewTabChanged();
+
+#if !DISABLE_UPDATE_DETECTION
             if (pref.ShouldCheck4UpdateOnStartup())
                 Check4Update();
 #endif
         }
 
+        private void HandleOpenReposInNewTabChanged()
+        {
+            var pref = ViewModels.Preferences.Instance;
+            
+            if (pref.OpenReposInNewTab)
+            {
+                if (_ipcServerTask == null || _ipcServerTask.IsCompleted)
+                {
+                    // Start IPC server
+                    _ipcServerCts = new CancellationTokenSource();
+                    _ipcServerTask = Task.Run(() => StartIPCServer(_ipcServerCts.Token));
+                }
+            }
+            else
+            {
+                // Stop IPC server if running
+                if (_ipcServerCts != null && !_ipcServerCts.IsCancellationRequested)
+                {
+                    _ipcServerCts.Cancel();
+                    _ipcServerCts.Dispose();
+                    _ipcServerCts = null;
+                }
+                _ipcServerTask = null;
+            }
+        }
+
+        private void StartIPCServer(CancellationToken cancellationToken)
+        {
+            try
+            {
+                while (!cancellationToken.IsCancellationRequested)
+                {
+                    using var server = new NamedPipeServerStream("SourceGitIPC", PipeDirection.In);
+                    
+                    // Use WaitForConnectionAsync with cancellation token
+                    try
+                    {
+                        Task connectionTask = server.WaitForConnectionAsync(cancellationToken);
+                        connectionTask.Wait(cancellationToken);
+                    }
+                    catch (OperationCanceledException)
+                    {
+                        return;
+                    }
+                    catch (AggregateException ae) when (ae.InnerExceptions.Any(e => e is OperationCanceledException))
+                    {
+                        return;
+                    }
+
+                    // Process the connection
+                    using var reader = new StreamReader(server);
+                    var repoPath = reader.ReadLine();
+
+                    if (!string.IsNullOrEmpty(repoPath) && Directory.Exists(repoPath))
+                    {
+                        Dispatcher.UIThread.Post(() =>
+                        {
+                            try
+                            {
+                                var test = new Commands.QueryRepositoryRootPath(repoPath).ReadToEnd();
+
+                                if (test.IsSuccess && !string.IsNullOrEmpty(test.StdOut))
+                                {
+                                    var repoRootPath = test.StdOut.Trim();
+                                    var pref = ViewModels.Preferences.Instance;
+                                    var node = pref.FindOrAddNodeByRepositoryPath(repoRootPath, null, false);
+
+                                    ViewModels.Welcome.Instance.Refresh();
+
+                                    _launcher?.OpenRepositoryInTab(node, null);
+
+                                    if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop && desktop.MainWindow != null)
+                                        desktop.MainWindow.Activate();
+                                }
+                            }
+                            catch (Exception)
+                            {
+                            }
+                        });
+                    }
+                }
+            }
+            catch (Exception)
+            {
+                // Pipe server failed, we can just exit the thread
+            }
+        }
+
         private void Check4Update(bool manually = false)
         {
             Task.Run(async () =>
@@ -584,5 +723,7 @@ namespace SourceGit
         private ResourceDictionary _activeLocale = null;
         private ResourceDictionary _themeOverrides = null;
         private ResourceDictionary _fontsOverrides = null;
+        private Task _ipcServerTask = null;
+        private CancellationTokenSource _ipcServerCts = null;
     }
 }

src/Resources/Locales/en_US.axaml

@@ -752,4 +752,5 @@
   <x:String x:Key="Text.Worktree.Lock" xml:space="preserve">Lock</x:String>
   <x:String x:Key="Text.Worktree.Remove" xml:space="preserve">Remove</x:String>
   <x:String x:Key="Text.Worktree.Unlock" xml:space="preserve">Unlock</x:String>
+  <x:String x:Key="Text.Preferences.General.OpenReposInNewTab" xml:space="preserve">Open repositories in new tab instead of new window</x:String>
 </ResourceDictionary>

src/ViewModels/Preferences.cs

@@ -90,6 +90,12 @@ namespace SourceGit.ViewModels
             }
         }
 
+        public bool OpenReposInNewTab
+        {
+            get => _openReposInNewTab;
+            set => SetProperty(ref _openReposInNewTab, value);
+        }
+
         public bool UseSystemWindowFrame
         {
             get => _useSystemWindowFrame;
@@ -632,6 +638,7 @@ namespace SourceGit.ViewModels
         private string _defaultFontFamily = string.Empty;
         private string _monospaceFontFamily = string.Empty;
         private bool _onlyUseMonoFontInEditor = false;
+        private bool _openReposInNewTab = false;
         private bool _useSystemWindowFrame = false;
         private double _defaultFontSize = 13;
         private double _editorFontSize = 13;

src/Views/Preferences.axaml

@@ -46,7 +46,7 @@
           <TabItem.Header>
             <TextBlock Classes="tab_header" Text="{DynamicResource Text.Preferences.General}"/>
           </TabItem.Header>
-          <Grid Margin="8" RowDefinitions="32,32,32,32,32,32,32,32,Auto" ColumnDefinitions="Auto,*">
+          <Grid Margin="8" RowDefinitions="32,32,32,32,32,32,32,32,32,Auto" ColumnDefinitions="Auto,*">
             <TextBlock Grid.Row="0" Grid.Column="0"
                        Text="{DynamicResource Text.Preferences.General.Locale}"
                        HorizontalAlignment="Right"
@@ -142,6 +142,11 @@
                       IsChecked="{Binding Source={x:Static vm:Preferences.Instance}, Path=ShowChildren, Mode=TwoWay}"/>
 
             <CheckBox Grid.Row="8" Grid.Column="1"
+                      Height="32"
+                      Content="{DynamicResource Text.Preferences.General.OpenReposInNewTab}"
+                      IsChecked="{Binding Source={x:Static vm:Preferences.Instance}, Path=OpenReposInNewTab, Mode=TwoWay}"/>
+
+            <CheckBox Grid.Row="9" Grid.Column="1"
                       Height="32"
                       Content="{DynamicResource Text.Preferences.General.Check4UpdatesOnStartup}"
                       IsVisible="{x:Static s:App.IsCheckForUpdateCommandVisible}"