Add command interruption support with Ctrl+C and cancellation tokens

Kernel.cs

@@ -34,6 +34,8 @@ public class Kernel : Sys.Kernel
         Sys.Mouse.MouseManager.Initialize();
         Sys.Mouse.MouseManager.SetScreenSize((int)canvas.Mode.Width, (int)canvas.Mode.Height);
         Sys.Keyboard.KeyboardManager.Initialize();
+
+        ProcessManager.SpawnProcess<CliProcess>();
     }
 
     protected override void Run()

Processes/CliProcess.cs

@@ -11,6 +11,8 @@ internal class CliProcess() : Process("Cli")
 
     private bool commandRunning = false;
 
+    private CancellationTokenSource? commandCancellationTokenSource = null;
+
     internal override void Start(string[] args)
     {
         Console.Clear();
@@ -23,10 +25,20 @@ internal class CliProcess() : Process("Cli")
 
     internal override async void Tick()
     {
-        while (Console.KeyAvailable && !commandRunning)
+        while (Console.KeyAvailable)
         {
             ConsoleKeyInfo key = Console.ReadKey(intercept: true);
 
+            if (commandRunning)
+            {
+                if (key.Key == ConsoleKey.C && key.Modifiers.HasFlag(ConsoleModifiers.Control) && commandCancellationTokenSource is not null)
+                {
+                    await commandCancellationTokenSource.CancelAsync();
+                }
+
+                continue;
+            }
+
             switch (key.Key)
             {
                 case ConsoleKey.Enter:
@@ -87,9 +99,10 @@ internal class CliProcess() : Process("Cli")
             return;
         }
 
+        commandCancellationTokenSource = new CancellationTokenSource();
         commandRunning = true;
 
-        bool handled = await CommandManager.TryExecute(input, Console.WriteLine);
+        bool handled = await CommandManager.TryExecuteAsync(input, Console.WriteLine, commandCancellationTokenSource.Token);
 
         if (!handled)
         {
@@ -97,5 +110,7 @@ internal class CliProcess() : Process("Cli")
         }
 
         commandRunning = false;
+        commandCancellationTokenSource.Dispose();
+        commandCancellationTokenSource = null;
     }
 }

Processes/TerminalProcess.cs

@@ -14,6 +14,8 @@ public class TerminalProcess() : Process("Terminal")
     private Window window = null!;
     private readonly List<string> history = [];
     private int historyIndex = -1;
+    private bool commandRunning = false;
+    private CancellationTokenSource? commandCancellationTokenSource = null;
     private string currentInput = "";
     private readonly List<Text> textLines = [];
     private readonly Lock textLinesLock = new();
@@ -49,6 +51,16 @@ public class TerminalProcess() : Process("Terminal")
 
     private async void HandleKey(KeyEvent keyEvent)
     {
+        if (commandRunning)
+        {
+            if (keyEvent.Key == ConsoleKeyEx.C && keyEvent.Modifiers.HasFlag(ConsoleModifiers.Control) && commandCancellationTokenSource is not null)
+            {
+                await commandCancellationTokenSource.CancelAsync();
+            }
+
+            return;
+        }
+
         if (keyEvent.Key == ConsoleKeyEx.Enter)
         {
             string cmd = currentInput;
@@ -72,16 +84,19 @@ public class TerminalProcess() : Process("Terminal")
                 }
                 else
                 {
-                    window.OnKeyEvent -= HandleKey;
+                    commandCancellationTokenSource = new CancellationTokenSource();
+                    commandRunning = true;
 
-                    bool handled = await CommandManager.TryExecute(cmd, PrintLine);
+                    bool handled = await CommandManager.TryExecuteAsync(cmd, PrintLine, commandCancellationTokenSource.Token);
 
                     if (!handled)
                     {
                         PrintLine($"\"{cmd}\" is not a command");
                     }
 
-                    window.OnKeyEvent += HandleKey;
+                    commandRunning = false;
+                    commandCancellationTokenSource.Dispose();
+                    commandCancellationTokenSource = null;
                 }
 
                 historyIndex = CommandManager.GetCommandHistory().Count;

UI/CLI/CommandManager.cs

@@ -29,7 +29,7 @@ public static class CommandManager
         return commandHistory;
     }
 
-    public static async Task<bool> TryExecute(string input, Action<string> printLine)
+    public static async Task<bool> TryExecuteAsync(string input, Action<string> printLine, CancellationToken cancellationToken = default)
     {
         string trimmedInput = input.Trim();
 
@@ -43,8 +43,7 @@ public static class CommandManager
             commandHistory.Add(trimmedInput);
         }
 
-        foreach (KeyValuePair<string, ICommand> entry in commands
+        foreach (KeyValuePair<string, ICommand> entry in commands.OrderByDescending(entry => entry.Key.Length))
-                     .OrderByDescending(entry => entry.Key.Length))
         {
             string commandName = entry.Key;
 
@@ -61,6 +60,8 @@ public static class CommandManager
                 arguments = trimmedInput[commandName.Length..].TrimStart();
             }
 
+            cancellationToken.Register(async () => await entry.Value.StopAsync());
+
             await entry.Value.ExecuteAsync(arguments, printLine);
             return true;
         }

UI/CLI/Commands/StartGuiCommand.cs

@@ -18,11 +18,6 @@ public class StartGuiCommand : ICommand
             return Task.CompletedTask;
         }
 
-        foreach (Process process in ProcessManager.GetProcessesOfType<CliProcess>())
-        {
-            ProcessManager.StopProcess(process.Id);
-        }
-
         _ = ProcessManager.SpawnProcess<DesktopProcess>();
         return Task.CompletedTask;
     }

UI/CLI/Commands/StopGuiCommand.cs

@@ -22,7 +22,5 @@ public class StopGuiCommand : ICommand
         {
             await ProcessManager.StopProcessAndWaitAsync(process.Id);
         }
-
-        _ = ProcessManager.SpawnProcess<CliProcess>();
     }
 }

UI/CLI/Commands/YesNtCommand.cs

@@ -12,10 +12,18 @@ namespace RemSox.UI.CLI.Commands
 
         public string Description => "Start the YesNt interpreter";
 
+        private int processId;
+
         public async Task ExecuteAsync(string? arguments, Action<string> printLine)
         {
-            int processId = ProcessManager.SpawnProcess<Processes.YesNtInterpreterProcess>(arguments?.Split(',') ?? []);
+            processId = ProcessManager.SpawnProcess<Processes.YesNtInterpreterProcess>(arguments?.Split(',') ?? []);
             await ProcessManager.WaitForProcessExitAsync(processId);
         }
+
+        public Task StopAsync()
+        {
+            ProcessManager.StopProcess(processId);
+            return Task.CompletedTask;
+        }
     }
 }

UI/CLI/ICommand.cs

@@ -20,4 +20,9 @@ public interface ICommand
     /// <param name="arguments">The arguments provided to the command.</param>
     /// <param name="printLine">A delegate to stream output lines to the current console or terminal.</param>
     Task ExecuteAsync(string? arguments, Action<string> printLine);
+
+    /// <summary>
+    /// Interrupts the command if it's currently running. This is called when the user presses Ctrl+C in the CLI.
+    /// </summary>
+    Task StopAsync() => Task.CompletedTask;
 }