FilePreview use ASCII only, force rerender when item disappears

src/ConsoleApp/FileTime.ConsoleUI.App/Controls/ItemPreviews.cs

@@ -79,9 +79,11 @@ public class ItemPreviews
                             .Setup(t => t.Bind(
                                 t,
                                 dc => dc.TextContent,
-                                t => t.Text)),
+                                t => t.Text,
+                                fallbackValue: string.Empty)),
                         new TextBlock<IElementPreviewViewModel>
                         {
+                            Margin = "0 1 0 0",
                             Extensions = {new GridPositionExtension(0, 1)}
                         }.Setup(t => t.Bind(
                             t,

src/Library/TerminalUI/Binding.cs

@@ -2,7 +2,6 @@
 using System.Linq.Expressions;
 using System.Reflection;
 using TerminalUI.Controls;
-using TerminalUI.ExpressionTrackers;
 using TerminalUI.Traits;
 
 namespace TerminalUI;

src/Library/TerminalUI/ConsoleDrivers/DotnetDriver.cs

@@ -6,7 +6,11 @@ namespace TerminalUI.ConsoleDrivers;
 
 public class DotnetDriver : IConsoleDriver
 {
+    protected bool CheckThreadId;
     public bool SupportsAnsiEscapeSequence { get; protected set; }
+    public int ThreadId { get; set; }
+
+    public void EnterRestrictedMode() => CheckThreadId = true;
 
     public virtual bool Init()
     {
@@ -25,10 +29,31 @@ public class DotnetDriver : IConsoleDriver
         return new(x, y);
     }
 
-    public void Write(string text) => Console.Out.Write(text);
+    public void Write(string text)
-    public void Write(ReadOnlySpan<char> text) => Console.Out.Write(text);
+    {
+        CheckThread();
+        Console.Out.Write(text);
+    }
 
-    public void Write(char text) => Console.Out.Write(text);
+    public void Write(ReadOnlySpan<char> text)
+    {
+        CheckThread();
+        Console.Out.Write(text);
+    }
+
+    public void Write(char text)
+    {
+        CheckThread();
+        Console.Out.Write(text);
+    }
+
+    private void CheckThread()
+    {
+        if (CheckThreadId && ThreadId != Thread.CurrentThread.ManagedThreadId)
+        {
+            throw new InvalidOperationException("Cannot write to console from another thread");
+        }
+    }
 
     public virtual void Dispose() => Console.Clear();
 

src/Library/TerminalUI/ConsoleDrivers/IConsoleDriver.cs

@@ -6,6 +6,7 @@ namespace TerminalUI.ConsoleDrivers;
 public interface IConsoleDriver
 {
     bool SupportsAnsiEscapeSequence { get; }
+    int ThreadId { get; set; }
     bool Init();
     void Dispose();
     void SetCursorPosition(Position position);
@@ -22,4 +23,5 @@ public interface IConsoleDriver
     void SetBackgroundColor(IColor background);
     Size GetWindowSize();
     void Clear();
+    void EnterRestrictedMode();
 }

src/Library/TerminalUI/ConsoleDrivers/XTermDriver.cs

@@ -28,6 +28,7 @@ public sealed class XTermDriver : DotnetDriver
 
     public override void Dispose()
     {
+        CheckThreadId = false;
         Write("\x1b[?1047l");
         SetCursorPosition(_initialCursorPosition);
     }

src/Library/TerminalUI/Controls/ChildCollectionView.cs

@@ -1,6 +1,5 @@
 using System.Collections.ObjectModel;
 using System.ComponentModel;
-using System.Diagnostics.CodeAnalysis;
 
 namespace TerminalUI.Controls;
 

src/Library/TerminalUI/Controls/StackPanel.cs

@@ -96,37 +96,6 @@ public sealed partial class StackPanel<T> : ChildCollectionView<StackPanel<T>, T
                 : childSize.Width;
         }
 
-        if (Orientation == Orientation.Horizontal)
-        {
-            var leftWidth = size.Width - delta;
-            Span<char> text = stackalloc char[leftWidth];
-            text.Fill(ApplicationContext!.EmptyCharacter);
-
-            SetColorsForDriver(renderContext);
-            RenderText(
-                text,
-                renderContext,
-                position with {X = position.X + delta},
-                size with {Width = leftWidth},
-                !neededRerender
-            );
-        }
-        else
-        {
-            var leftHeight = size.Height - delta;
-            Span<char> text = stackalloc char[size.Width];
-            text.Fill(ApplicationContext!.EmptyCharacter);
-
-            SetColorsForDriver(renderContext);
-            RenderText(
-                text,
-                renderContext,
-                position with {Y = position.Y + delta},
-                size with {Height = leftHeight},
-                !neededRerender
-            );
-        }
-
         return neededRerender;
     }
 

src/Library/TerminalUI/Controls/TextBlock.cs

@@ -21,7 +21,6 @@ public sealed partial class TextBlock<T> : View<TextBlock<T>, T>, IDisplayView
 
     private RenderState? _lastRenderState;
     private string[]? _textLines;
-    private bool _placeholderRenderDone;
 
     [Notify] private string? _text = string.Empty;
     [Notify] private TextAlignment _textAlignment = TextAlignment.Left;
@@ -64,30 +63,22 @@ public sealed partial class TextBlock<T> : View<TextBlock<T>, T>, IDisplayView
 
         _lastRenderState = renderState;
 
-        if (_textLines is null)
+        var textLines = _textLines;
+        var textStartIndex = _textStartIndex;
+        if (textLines is null)
         {
-            if (!_placeholderRenderDone)
-            {
-                _placeholderRenderDone = true;
-                RenderEmpty(renderContext, position, size, skipRender);
-                return true;
-            }
-
             return false;
         }
 
-        _placeholderRenderDone = false;
-
         SetStyleColor(renderContext, foreground, background, _textFormat);
 
-        var textLines = _textLines;
+        if (textStartIndex < textLines.Length)
-        if (_textStartIndex < _textLines.Length)
         {
-            textLines = _textLines[_textStartIndex..];
+            textLines = textLines[textStartIndex..];
         }
         else
         {
-            _textStartIndex = _textLines.Length - size.Height;
+            _textStartIndex = textLines.Length - size.Height;
         }
 
         RenderText(textLines, renderContext, position, size, skipRender, TransformText);
@@ -99,7 +90,7 @@ public sealed partial class TextBlock<T> : View<TextBlock<T>, T>, IDisplayView
         => TextAlignment switch
         {
             TextAlignment.Right => string.Format($"{{0,{size.Width}}}", text),
-            _ => string.Format($"{{0,{-size.Width}}}", text)
+            _ => text
         };
 
     private bool NeedsRerender(RenderState renderState)

src/Library/TerminalUI/Controls/TextBox.cs

@@ -103,11 +103,8 @@ public sealed partial class TextBox<T> : View<TextBox<T>, T>, IFocusable, IDispl
         var skipRender = !renderContext.ForceRerender && !NeedsRerender(renderStatus);
         _lastRenderState = renderStatus;
 
-        var driver = renderContext.ConsoleDriver;
         SetStyleColor(renderContext, foreground, background);
 
-        RenderEmpty(renderContext, position, size, skipRender);
-
         if (PasswordChar is { } passwordChar && !char.IsControl(passwordChar))
         {
             for (var i = 0; i < _textLines.Count; i++)

src/Library/TerminalUI/Controls/View.cs

@@ -132,7 +132,7 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
         }
         else if (e.PropertyName == nameof(IsVisible))
         {
-            ApplicationContext?.RenderEngine.VisibilityChanged(this);
+            ApplicationContext?.RenderEngine.VisibilityChanged(this, IsVisible);
         }
     }
 
@@ -218,7 +218,7 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
         }
     }
 
-    private void UpdateCells(bool[,] renderContextUpdatedCells, Position position, int sizeWidth, int sizeHeight)
+    private static void UpdateCells(bool[,] renderContextUpdatedCells, Position position, int sizeWidth, int sizeHeight)
     {
         for (var x = 0; x < sizeWidth; x++)
         {
@@ -235,14 +235,12 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
         Position position,
         Size size,
         bool updateCellsOnly,
-        TextTransformer? textTransformer = null)
+        TextTransformer? textTransformer = null,
+        bool useAsciiOnly = true)
     {
-        UpdateCells(renderContext.UpdatedCells, position, size.Width, size.Height);
-
-        if (updateCellsOnly) return;
-
         var driver = renderContext.ConsoleDriver;
-        for (var i = 0; i < textLines.Count; i++)
+        var end = int.Min(textLines.Count, size.Height);
+        for (var i = 0; i < end; i++)
         {
             var currentPosition = position with {Y = position.Y + i};
             var text = textLines[i];
@@ -252,15 +250,32 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
                 text = textTransformer(text, currentPosition, size);
             }
 
+            if (useAsciiOnly)
+            {
+                RenderTextAsciiOnly(
+                    text,
+                    renderContext,
+                    currentPosition,
+                    size.Width,
+                    updateCellsOnly);
+            }
+            else
+            {
                 if (text.Length > size.Width)
                 {
                     text = text[..size.Width];
                 }
-            else if (text.Length < size.Width)
+
+
+                foreach (var c in text)
                 {
-                text = text.PadRight(size.Width);
+                    if (char.IsControl(c))
+                        throw new Exception("Control character");
                 }
 
+                if (updateCellsOnly) continue;
+                UpdateCells(renderContext.UpdatedCells, currentPosition, text.Length, 1);
+
                 try
                 {
                     driver.SetCursorPosition(currentPosition);
@@ -271,6 +286,7 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
                 }
             }
         }
+    }
 
     protected void RenderText(
         in ReadOnlySpan<char> text,
@@ -279,10 +295,6 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
         Size size,
         bool updateCellsOnly)
     {
-        UpdateCells(renderContext.UpdatedCells, position, size.Width, size.Height);
-
-        if (updateCellsOnly) return;
-
         var driver = renderContext.ConsoleDriver;
         for (var i = 0; i < size.Height; i++)
         {
@@ -294,6 +306,9 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
                 finalText = finalText[..size.Width];
             }
 
+            UpdateCells(renderContext.UpdatedCells, currentPosition, finalText.Length, 1);
+            if (updateCellsOnly) continue;
+
             driver.SetCursorPosition(currentPosition);
             driver.Write(finalText);
         }
@@ -311,7 +326,8 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
         if (updateCellsOnly) return;
 
         var driver = renderContext.ConsoleDriver;
-        var contentString = new string(content, size.Width);
+        Span<char> contentString = stackalloc char[size.Width];
+        contentString.Fill(content);
 
         for (var i = 0; i < size.Height; i++)
         {
@@ -322,6 +338,37 @@ public abstract partial class View<TConcrete, T> : IView<T> where TConcrete : Vi
         }
     }
 
+    private void RenderTextAsciiOnly(
+        ReadOnlySpan<char> text,
+        in RenderContext renderContext,
+        Position position,
+        int width,
+        bool updateCellsOnly)
+    {
+        Span<char> finalText = stackalloc char[width];
+
+        var finalTextPosition = 0;
+        for (var i = 0; i < text.Length && finalTextPosition < width; i++)
+        {
+            var c = text[i];
+            if (c < 32 || c > 255) continue;
+
+            finalText[finalTextPosition] = c;
+            finalTextPosition++;
+        }
+
+        for (var i = 0; i < finalTextPosition; i++)
+        {
+            renderContext.UpdatedCells[position.X + i, position.Y] = true;
+        }
+
+        if (updateCellsOnly) return;
+
+        var driver = renderContext.ConsoleDriver;
+        driver.SetCursorPosition(position);
+        driver.Write(finalText[..finalTextPosition]);
+    }
+
     protected void SetStyleColor(
         in RenderContext renderContext,
         IColor? foreground = null,

src/Library/TerminalUI/EventLoop.cs

@@ -1,5 +1,4 @@
-using System.Diagnostics;
+using Microsoft.Extensions.Logging;
-using Microsoft.Extensions.Logging;
 
 namespace TerminalUI;
 
@@ -7,8 +6,11 @@ public class EventLoop : IEventLoop
 {
     private readonly IApplicationContext _applicationContext;
     private readonly ILogger<EventLoop> _logger;
+    private readonly List<Action> _initializers = new();
     private readonly List<Action> _permanentQueue = new();
 
+    public int ThreadId { get; set; } = -1;
+    
     public EventLoop(
         IApplicationContext applicationContext,
         ILogger<EventLoop> logger)
@@ -18,15 +20,22 @@ public class EventLoop : IEventLoop
     }
 
     public void AddToPermanentQueue(Action action) => _permanentQueue.Add(action);
+    public void AddInitializer(Action action) => _initializers.Add(action);
 
     public void Run()
     {
         _applicationContext.IsRunning = true;
+        ThreadId = Thread.CurrentThread.ManagedThreadId;
+        foreach (var initializer in _initializers)
+        {
+            initializer();
+        }
         while (_applicationContext.IsRunning)
         {
             ProcessQueues();
             Thread.Sleep(10);
         }
+        ThreadId = -1;
     }
 
     private void ProcessQueues()

src/Library/TerminalUI/IEventLoop.cs

@@ -4,4 +4,6 @@ public interface IEventLoop
 {
     void Run();
     void AddToPermanentQueue(Action action);
+    void AddInitializer(Action action);
+    int ThreadId { get; set; }
 }

src/Library/TerminalUI/IRenderEngine.cs

@@ -5,7 +5,7 @@ namespace TerminalUI;
 public interface IRenderEngine
 {
     void RequestRerender(IView view);
-    void VisibilityChanged(IView view);
+    void VisibilityChanged(IView view, bool newVisibility);
     void AddViewToPermanentRenderGroup(IView view);
     void Run();
 }

src/Library/TerminalUI/RenderEngine.cs

@@ -1,5 +1,4 @@
-using TerminalUI.ConsoleDrivers;
+using TerminalUI.Controls;
-using TerminalUI.Controls;
 using TerminalUI.Models;
 using TerminalUI.TextFormat;
 using TerminalUI.Traits;
@@ -15,9 +14,11 @@ public class RenderEngine : IRenderEngine
     private readonly List<IView> _forcedTemporaryViewsToRender = new();
     private bool _rerenderRequested = true;
     private bool _lastCursorVisible;
+    private bool _forceRerenderAll;
     private bool[,]? _updatedCells;
     private bool[,]? _filledCells;
     private bool[,]? _lastFilledCells;
+    private DateTime _renderRequestDetected;
 
     public RenderEngine(IApplicationContext applicationContext, IEventLoop eventLoop)
     {
@@ -25,12 +26,23 @@ public class RenderEngine : IRenderEngine
         _eventLoop = eventLoop;
 
         _eventLoop.AddToPermanentQueue(Render);
+        _eventLoop.AddInitializer(() =>
+        {
+            _applicationContext.ConsoleDriver.ThreadId = _eventLoop.ThreadId;
+            _applicationContext.ConsoleDriver.EnterRestrictedMode();
+        });
     }
 
     public void RequestRerender(IView view) => RequestRerender();
 
-    public void VisibilityChanged(IView view)
+    public void VisibilityChanged(IView view, bool newVisibility)
     {
+        if (!newVisibility)
+        {
+            _forceRerenderAll = true;
+            return;
+        }
+
         IVisibilityChangeHandler? visibilityChangeHandler = null;
         var parent = view.VisualParent;
         while (parent?.VisualParent != null)
@@ -46,13 +58,12 @@ public class RenderEngine : IRenderEngine
 
         if (visibilityChangeHandler is null)
         {
-            AddViewToForcedTemporaryRenderGroup(parent ?? view);
+            //AddViewToForcedTemporaryRenderGroup(parent ?? view);
+            return;
         }
-        else
+
-        {
         visibilityChangeHandler.ChildVisibilityChanged(view);
     }
-    }
 
     public void Run() => _eventLoop.Run();
 
@@ -68,6 +79,7 @@ public class RenderEngine : IRenderEngine
     {
         List<IView> permanentViewsToRender;
         List<IView> forcedTemporaryViewsToRender;
+        bool forceRerenderAll;
         lock (_lock)
         {
             if (!_rerenderRequested) return;
@@ -75,6 +87,9 @@ public class RenderEngine : IRenderEngine
             permanentViewsToRender = _permanentViewsToRender.ToList();
             forcedTemporaryViewsToRender = _forcedTemporaryViewsToRender.ToList();
             _forcedTemporaryViewsToRender.Clear();
+
+            forceRerenderAll = _forceRerenderAll;
+            _forceRerenderAll = false;
         }
 
         var driver = _applicationContext.ConsoleDriver;
@@ -93,6 +108,8 @@ public class RenderEngine : IRenderEngine
             ClearArray2D(_updatedCells);
         }
 
+        if (!forceRerenderAll)
+        {
             RenderViews(
                 forcedTemporaryViewsToRender,
                 new RenderContext(
@@ -106,12 +123,13 @@ public class RenderEngine : IRenderEngine
                 ),
                 initialPosition,
                 size);
+        }
 
         RenderViews(
             permanentViewsToRender,
             new RenderContext(
                 driver,
-                false,
+                forceRerenderAll,
                 null,
                 null,
                 new RenderStatistics(),

src/Library/TerminalUI/TerminalUI.csproj

@@ -24,8 +24,4 @@
     </PackageReference>
   </ItemGroup>
 
-  <ItemGroup>
-    <Folder Include="KeyHandling\" />
-  </ItemGroup>
-
 </Project>