Add windowed terminal, basic text, rectangle rendering, and keyboard events

Kernel.cs

@@ -53,7 +53,7 @@ public class Kernel : Sys.Kernel
         if (Processes.DesktopProcess.IsRunning)
         {
             // Suspend the CLI while the GUI is active to prevent blocking and console corruption.
-            Thread.Sleep(100);
+            Thread.Sleep(1000);
             return;
         }
 

Processes/DesktopProcess.cs

@@ -29,20 +29,23 @@ public class DesktopProcess : Process
 
         // Trigger Canvas initialization
         FullScreenCanvas.GetFullScreenCanvas();
-        
+
         // Force existing windows to redraw onto the new canvas renderer
         WindowManager.InvalidateAll();
 
+        // Start the terminal process within the desktop environment
+        ProcessManager.SpawnProcess<TerminalProcess>();
+
         while (!StopRequested)
         {
             WindowManager.Update();
-            
+
             // Sleep slightly to yield CPU to the main CLI thread (approx 60 FPS)
-            Thread.Sleep(16);
+            //Thread.Sleep(16);
         }
-        
+
         IsRunning = false;
-        
+
         // Cosmos doesn't robustly support switching back to text mode yet.
         // We will stop updating, but the screen will remain in graphics mode.
     }

Processes/TerminalProcess.cs

@@ -0,0 +1,135 @@
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using Cosmos.Kernel.System;
+using Cosmos.Kernel.System.Keyboard;
+using RemSox.Processing;
+using RemSox.UI.GUI.UIEelements;
+using RemSox.UI.GUI.Windows;
+using RemSox.UI.GUI.CLI;
+
+namespace RemSox.Processes;
+
+public class TerminalProcess : Process
+{
+    private Window? window;
+    private readonly List<string> history = new();
+    private string currentInput = "";
+    private readonly List<Text> textLines = new();
+    private const int MaxLines = 15;
+    private const int LineHeight = 16;
+
+    public TerminalProcess() : base("Terminal")
+    {
+    }
+
+    internal override void Run()
+    {
+        window = WindowManager.CreateWindow(this, "Terminal", new Point(50, 50), new Size(400, 300));
+
+        for (int i = 0; i < MaxLines + 1; i++) // +1 for the input line
+        {
+            var textElement = window.CreateUIElement<Text>(t =>
+            {
+                t.Position = new Point(5, 20 + (i * LineHeight));
+                t.Color = Color.LightGreen;
+                t.Content = "";
+            });
+            textLines.Add(textElement);
+        }
+
+        window.AutoFlush = true;
+
+        PrintLine("RemSox GUI Terminal v1.0");
+        PrintLine("Type 'help' for commands.");
+
+        window.OnKeyEvent += HandleKey;
+
+        while (!StopRequested)
+        {
+            System.Threading.Thread.Sleep(50);
+        }
+
+        window.OnKeyEvent -= HandleKey;
+        WindowManager.CloseWindow(window);
+    }
+
+    private void HandleKey(KeyEvent keyEvent)
+    {
+        if (keyEvent.Key == ConsoleKeyEx.Enter)
+        {
+            string cmd = currentInput;
+            PrintLine("> " + cmd);
+            currentInput = "";
+
+            if (!string.IsNullOrWhiteSpace(cmd))
+            {
+                // Temporarily capture console output
+                // Wait, CommandManager uses Console.WriteLine.
+                // Redirecting Console output in Cosmos might be tricky.
+                // For now we will just execute it. Note: CommandManager commands write to standard Console, 
+                // which might write over the VGA buffer or just be invisible.
+                // To make a proper terminal, commands should return strings or we need a custom ICommand context.
+
+                if (cmd == "exit")
+                {
+                    RequestStop();
+                }
+                else
+                {
+                    bool found = CommandManager.TryExecute(cmd);
+                    if (!found)
+                    {
+                        PrintLine($"\"{cmd}\" is not a command");
+                    }
+                    else
+                    {
+                        PrintLine("Command executed. (Output sent to background console)");
+                    }
+                }
+            }
+            UpdateDisplay();
+        }
+        else if (keyEvent.Key == ConsoleKeyEx.Backspace)
+        {
+            if (currentInput.Length > 0)
+            {
+                currentInput = currentInput.Substring(0, currentInput.Length - 1);
+                UpdateDisplay();
+            }
+        }
+        else if (keyEvent.KeyChar >= 32 && keyEvent.KeyChar <= 126) // Printable chars
+        {
+            currentInput += keyEvent.KeyChar;
+            UpdateDisplay();
+        }
+    }
+
+    private void PrintLine(string text)
+    {
+        history.Add(text);
+        if (history.Count > MaxLines)
+        {
+            history.RemoveAt(0);
+        }
+        UpdateDisplay();
+    }
+
+    private void UpdateDisplay()
+    {
+        for (int i = 0; i < MaxLines; i++)
+        {
+            if (i < history.Count)
+            {
+                textLines[i].Content = history[i];
+            }
+            else
+            {
+                textLines[i].Content = "";
+            }
+        }
+
+        // The last line is the input line
+        textLines[MaxLines].Content = "> " + currentInput + "_";
+    }
+}

UI/GUI/Rendering/CanvasRenderSource.cs

@@ -3,6 +3,7 @@ using System.Drawing;
 using System.Collections.Generic;
 using System.Linq;
 using Cosmos.Kernel.System.Graphics;
+using Cosmos.Kernel.System.Graphics.Fonts;
 
 namespace RemSox.UI.GUI.Rendering;
 
@@ -12,15 +13,32 @@ public sealed class CanvasRenderSource : IRenderSource
     private static readonly Dictionary<int, Point> windowPositions = new();
     private static readonly Dictionary<int, int> windowZIndices = new();
 
+    private static bool isDirty = true;
+    private static Point lastPointerPosition = new Point(-1, -1);
+    private static List<int> orderedWindowsCache = new();
+    private static bool isZOrderDirty = true;
+
     public void Render(IEnumerable<RenderCommand> commands)
     {
+        bool changed = false;
         foreach (RenderCommand command in commands)
         {
+            changed = true;
+            if (command.ElementType == "WindowClose")
+            {
+                windowCanvases.Remove(command.WindowId);
+                windowPositions.Remove(command.WindowId);
+                windowZIndices.Remove(command.WindowId);
+                isZOrderDirty = true;
+                continue;
+            }
+
             if (command.ElementType == "Window" || command.ElementType == "WindowMove")
             {
                 if (command.Properties.TryGetValue("ZIndex", out object? rawZIndex) && rawZIndex is int z)
                 {
                     windowZIndices[command.WindowId] = z;
+                    isZOrderDirty = true;
                 }
             }
 
@@ -30,14 +48,14 @@ public sealed class CanvasRenderSource : IRenderSource
                     ? windowSize
                     : new Size(160, 120);
 
-                if (!windowCanvases.TryGetValue(command.WindowId, out Canvas? currentCanvas) || 
-                    currentCanvas.Mode.Width != size.Width || 
+                if (!windowCanvases.TryGetValue(command.WindowId, out Canvas? currentCanvas) ||
+                    currentCanvas.Mode.Width != size.Width ||
                     currentCanvas.Mode.Height != size.Height)
                 {
                     windowCanvases[command.WindowId] = new Canvas(size.Width, size.Height);
                 }
             }
-            
+
             if (!windowCanvases.ContainsKey(command.WindowId))
             {
                 windowCanvases[command.WindowId] = new Canvas(160, 120);
@@ -62,16 +80,40 @@ public sealed class CanvasRenderSource : IRenderSource
             {
                 RenderCircle(windowCanvas, command);
             }
+
+            if (command.ElementType == "Rectangle")
+            {
+                RenderRectangle(windowCanvas, command);
+            }
+
+            if (command.ElementType == "Text")
+            {
+                RenderText(windowCanvas, command);
+            }
+        }
+
+        if (changed)
+        {
+            isDirty = true;
         }
     }
 
     public static void CompositeAndDisplay(Canvas screenCanvas, Point pointerPosition)
     {
-        screenCanvas.Clear(Color.Black);
+        if (!isDirty && pointerPosition == lastPointerPosition)
+        {
+            return;
+        }
 
-        var orderedWindows = windowPositions.Keys.OrderBy(id => windowZIndices.TryGetValue(id, out int z) ? z : 0);
+        if (isZOrderDirty)
+        {
+            orderedWindowsCache = windowPositions.Keys.OrderBy(id => windowZIndices.TryGetValue(id, out int z) ? z : 0).ToList();
+            isZOrderDirty = false;
+        }
 
-        foreach (var windowId in orderedWindows)
+        //screenCanvas.Clear(Color.Black);
+
+        foreach (var windowId in orderedWindowsCache)
         {
             if (windowPositions.TryGetValue(windowId, out Point position) && windowCanvases.TryGetValue(windowId, out Canvas? windowCanvas))
             {
@@ -81,6 +123,9 @@ public sealed class CanvasRenderSource : IRenderSource
 
         screenCanvas.DrawFilledCircle(Color.White, pointerPosition.X, pointerPosition.Y, 5);
         screenCanvas.Display();
+
+        lastPointerPosition = pointerPosition;
+        isDirty = false;
     }
 
     private static void RenderWindow(Canvas canvas, RenderCommand command)
@@ -115,4 +160,42 @@ public sealed class CanvasRenderSource : IRenderSource
 
         canvas.DrawFilledCircle(color, centerX, centerY, radius);
     }
+
+    private static void RenderRectangle(Canvas canvas, RenderCommand command)
+    {
+        Color color = command.Properties.TryGetValue("Color", out object? rawColor) && rawColor is Color rectColor
+            ? rectColor
+            : Color.White;
+
+        Size size = command.Properties.TryGetValue("Size", out object? rawSize) && rawSize is Size rectSize
+            ? rectSize
+            : new Size(10, 10);
+
+        bool isFilled = command.Properties.TryGetValue("IsFilled", out object? rawFilled) && rawFilled is bool filled && filled;
+
+        if (isFilled)
+        {
+            canvas.DrawFilledRectangle(color, command.Position.X, command.Position.Y, size.Width, size.Height);
+        }
+        else
+        {
+            canvas.DrawRectangle(color, command.Position.X, command.Position.Y, size.Width, size.Height);
+        }
+    }
+
+    private static void RenderText(Canvas canvas, RenderCommand command)
+    {
+        Color color = command.Properties.TryGetValue("Color", out object? rawColor) && rawColor is Color textColor
+            ? textColor
+            : Color.White;
+
+        string content = command.Properties.TryGetValue("Content", out object? rawContent) && rawContent is string textContent
+            ? textContent
+            : string.Empty;
+
+        if (!string.IsNullOrEmpty(content))
+        {
+            canvas.DrawString(content, Cosmos.Kernel.System.Graphics.Fonts.PCScreenFont.DefaultFont, color, command.Position.X, command.Position.Y);
+        }
+    }
 }

UI/GUI/UIEelements/Shapes/Rectangle.cs

@@ -0,0 +1,18 @@
+using System.Drawing;
+
+namespace RemSox.UI.GUI.UIEelements.Shapes;
+
+public class Rectangle() : Shape("Rectangle")
+{
+    public Size Size
+    {
+        get;
+        set => SetProperty(nameof(Size), ref field, value);
+    }
+
+    public bool IsFilled
+    {
+        get;
+        set => SetProperty(nameof(IsFilled), ref field, value);
+    } = true;
+}

UI/GUI/UIEelements/Text.cs

@@ -0,0 +1,18 @@
+using System.Drawing;
+
+namespace RemSox.UI.GUI.UIEelements;
+
+public class Text() : UIElement("Text")
+{
+    public string Content
+    {
+        get;
+        set => SetProperty(nameof(Content), ref field, value);
+    } = string.Empty;
+
+    public Color Color
+    {
+        get;
+        set => SetProperty(nameof(Color), ref field, value);
+    } = Color.White;
+}

UI/GUI/Windows/Window.cs

@@ -18,6 +18,13 @@ public sealed class Window(string title, int processId, int id, IRenderSource re
 
     public bool AutoFlush { get; set; } = false;
 
+    public event Action<Cosmos.Kernel.System.Keyboard.KeyEvent>? OnKeyEvent;
+
+    public void HandleKeyEvent(Cosmos.Kernel.System.Keyboard.KeyEvent keyEvent)
+    {
+        OnKeyEvent?.Invoke(keyEvent);
+    }
+
     public bool IsFocused
     {
         get => WindowManager.IsWindowFocused(this);

UI/GUI/Windows/WindowManager.cs

@@ -5,6 +5,7 @@ using System.Drawing;
 using System.Linq;
 using Cosmos.Kernel.System.Graphics;
 using Cosmos.Kernel.System.Mouse;
+using Cosmos.Kernel.System.Keyboard;
 using RemSox.Processing;
 using RemSox.UI.GUI.Rendering;
 
@@ -51,6 +52,11 @@ public static class WindowManager
 
         wasLeftButtonDown = leftButtonDown;
 
+        if (KeyboardManager.TryReadKey(out KeyEvent keyEvent))
+        {
+            focusedWindow?.HandleKeyEvent(keyEvent);
+        }
+
         Canvas canvas = FullScreenCanvas.GetFullScreenCanvas();
         CanvasRenderSource.CompositeAndDisplay(canvas, pointerPosition);
 
@@ -86,6 +92,8 @@ public static class WindowManager
         {
             processWindows.Remove(window);
         }
+        
+        renderSource.Render(new[] { new RenderCommand { WindowId = window.Id, ElementId = window.Id, ElementType = "WindowClose", Position = window.Position, Properties = new Dictionary<string, object?>() } });
     }
 
     public static List<Window> GetWindowsForProcess(Process process)