Fixes #4004. Driver "windows" broken in conhost and cmd

Examples/UICatalog/Scenarios/Images.cs

@@ -246,7 +246,7 @@ protected override void Dispose (bool disposing)
         _sixelSupported.Dispose ();
         _isDisposed = true;
 
-        Application.Sixel.Clear ();
+        Application.Driver?.Sixel.Clear ();
     }
 
     private void OpenImage (object sender, CommandEventArgs e)

Examples/UICatalog/UICatalog.cs

@@ -57,7 +57,7 @@
 {
     private static string? _forceDriver;
     private static string? _uiCatalogDriver;
     private static string? _scenarioDriver;
 
     public static string LogFilePath { get; set; } = string.Empty;
     public static LoggingLevelSwitch LogLevelSwitch { get; } = new ();
@@ -433,8 +433,10 @@
 
             // This call to Application.Shutdown brackets the Application.Init call
             // made by Scenario.Init() above
-            // TODO: Throw if shutdown was not called already
-            Application.Shutdown ();
+            if (Application.Driver is { })
+            {
+                Application.Shutdown ();
+            }
 
             VerifyObjectsWereDisposed ();
 
@@ -482,8 +484,10 @@
 
         scenario.Dispose ();
 
-        // TODO: Throw if shutdown was not called already
-        Application.Shutdown ();
+        if (Application.Driver is { })
+        {
+            Application.Shutdown ();
+        }
 
         return results;
     }

Terminal.Gui/App/Application.Driver.cs

@@ -51,9 +51,9 @@ public static string ForceDriver
     /// <summary>Raised when <see cref="ForceDriver"/> changes.</summary>
     public static event EventHandler<ValueChangedEventArgs<string>>? ForceDriverChanged;
 
-    /// <inheritdoc cref="IApplication.Sixel"/>
-    [Obsolete ("The legacy static Application object is going away.")] 
-    public static List<SixelToRender> Sixel => ApplicationImpl.Instance.Sixel;
+    /// <inheritdoc cref="IDriver.Sixel"/>
+    [Obsolete ("The legacy static Application object is going away.")]
+    public static List<SixelToRender> Sixel => ApplicationImpl.Instance.Driver?.Sixel!;
 
     /// <summary>Gets a list of <see cref="IDriver"/> types and type names that are available.</summary>
     /// <returns></returns>

Terminal.Gui/App/Application.Lifecycle.cs

@@ -67,7 +67,13 @@ public static int? MainThreadId
 
     /// <inheritdoc cref="IDisposable.Dispose"/>
     [Obsolete ("The legacy static Application object is going away.")]
-    public static void Shutdown () => ApplicationImpl.Instance.Dispose ();
+    public static void Shutdown ()
+    {
+        ApplicationImpl.Instance.Dispose ();
+
+        // Use the static reset method to bypass the fence check
+        ApplicationImpl.ResetStateStatic ();
+    }
 
     /// <inheritdoc cref="IApplication.Initialized"/>
     [Obsolete ("The legacy static Application object is going away.")]

Terminal.Gui/App/ApplicationImpl.Driver.cs

@@ -13,9 +13,6 @@ internal partial class ApplicationImpl
     /// <inheritdoc/>
     public string ForceDriver { get; set; } = string.Empty;
 
-    /// <inheritdoc/>
-    public List<SixelToRender> Sixel { get; } = new ();
-
     /// <summary>
     ///     Creates the appropriate <see cref="IDriver"/> based on platform and driverName.
     /// </summary>

Terminal.Gui/App/ApplicationImpl.Lifecycle.cs

@@ -310,17 +310,14 @@ public void ResetState (bool ignoreDisposed = false)
         Initialized = false;
         MainThreadId = null;
 
-        // === 9. Clear graphics ===
-        Sixel.Clear ();
-
-        // === 10. Reset ForceDriver ===
+        // === 9. Reset ForceDriver ===
         // Note: ForceDriver and Force16Colors are reset
         // If they need to persist across Init/Shutdown cycles
         // then the user of the library should manage that state
         Force16Colors = false;
         ForceDriver = string.Empty;
 
-        // === 11. Reset synchronization context ===
+        // === 10. Reset synchronization context ===
         // IMPORTANT: Always reset sync context, even if not initialized
         // This ensures cleanup works correctly even if Shutdown is called without Init
         // Reset synchronization context to allow the user to run async/await,
@@ -329,7 +326,7 @@ public void ResetState (bool ignoreDisposed = false)
         // (https://github.com/gui-cs/Terminal.Gui/issues/1084).
         SynchronizationContext.SetSynchronizationContext (null);
 
-        // === 12. Unsubscribe from Application static property change events ===
+        // === 11. Unsubscribe from Application static property change events ===
         UnsubscribeApplicationEvents ();
     }
 

Terminal.Gui/App/IApplication.cs

@@ -497,12 +497,6 @@ public IApplication Run<TRunnable> (Func<Exception, bool>? errorHandler = null,
     /// </remarks>
     bool ClearScreenNextIteration { get; set; }
 
-    /// <summary>
-    ///     Collection of sixel images to write out to screen when updating.
-    ///     Only add to this collection if you are sure terminal supports sixel format.
-    /// </summary>
-    List<SixelToRender> Sixel { get; }
-
     #endregion Screen and Driver
 
     #region Keyboard

Terminal.Gui/Drawing/Sixel/SixelSupportDetector.cs

@@ -33,7 +33,7 @@ public SixelSupportDetector (IDriver? driver) : this ()
     public void Detect (Action<SixelSupportResult> resultCallback)
     {
         var result = new SixelSupportResult ();
-        result.SupportsTransparency = IsVirtualTerminal () || IsXtermWithTransparency ();
+        result.SupportsTransparency = IsVirtualTerminal () && IsXtermWithTransparency ();
         IsSixelSupportedByDar (result, resultCallback);
     }
 
@@ -155,9 +155,9 @@ private void QueueRequest (AnsiEscapeSequence req, Action<string> responseCallba
 
     private static bool ResponseIndicatesSupport (string response) { return response.Split (';').Contains ("4"); }
 
-    private static bool IsVirtualTerminal ()
+    private bool IsVirtualTerminal ()
     {
-        return !string.IsNullOrWhiteSpace (Environment.GetEnvironmentVariable ("WT_SESSION"));
+        return (_driver as DriverImpl)?.IsVirtualTerminal == true;
     }
 
     private static bool IsXtermWithTransparency ()

Terminal.Gui/Drivers/DotNetDriver/NetOutput.cs

@@ -30,6 +30,8 @@ public NetOutput ()
         {
             _isWinPlatform = true;
         }
+
+        IsVirtualTerminal = true;
     }
 
     /// <inheritdoc/>

Terminal.Gui/Drivers/DriverImpl.cs

@@ -72,6 +72,31 @@ ISizeMonitor sizeMonitor
                                    };
 
         CreateClipboard ();
+
+        if (_output is OutputBase outputBase)
+        {
+            IsVirtualTerminal = outputBase.IsVirtualTerminal;
+            outputBase.Driver = this;
+        }
+    }
+
+    private bool _isVirtualTerminal = true;
+
+    /// <summary>
+    ///     Gets or sets whether <see cref="IDriver"/> support for virtualized terminal sequences.
+    /// </summary>
+    internal bool IsVirtualTerminal
+    {
+        get => _isVirtualTerminal;
+        set
+        {
+            _isVirtualTerminal = value;
+
+            if (!_isVirtualTerminal)
+            {
+                Force16Colors = true;
+            }
+        }
     }
 
     /// <inheritdoc/>
@@ -199,16 +224,34 @@ public int Top
 
     /// <inheritdoc/>
 
-    public bool SupportsTrueColor => true;
+    public bool SupportsTrueColor => _isVirtualTerminal;
 
     /// <inheritdoc/>
 
     public bool Force16Colors
     {
-        get => Application.Force16Colors || !SupportsTrueColor;
-        set => Application.Force16Colors = value || !SupportsTrueColor;
+        get => Application.Force16Colors;
+        set
+        {
+            if (!_isVirtualTerminal && !Application.Force16Colors)
+            {
+                Application.Force16Colors = true;
+
+                return;
+            }
+
+            if (!_isVirtualTerminal && !value)
+            {
+                return;
+            }
+
+            Application.Force16Colors = value;
+        }
     }
 
+    /// <inheritdoc/>
+    public List<SixelToRender> Sixel { get; } = [];
+
     /// <inheritdoc/>
 
     public Attribute CurrentAttribute
@@ -362,7 +405,7 @@ public Attribute SetAttribute (Attribute newAttribute)
     public void EnqueueKeyEvent (Key key) { InputProcessor.EnqueueKeyDownEvent (key); }
 
     /// <inheritdoc/>
-    public void QueueAnsiRequest (AnsiEscapeSequenceRequest request) { _ansiRequestScheduler.SendOrSchedule (this, request); }
+    public virtual void QueueAnsiRequest (AnsiEscapeSequenceRequest request) { _ansiRequestScheduler.SendOrSchedule (this, request); }
 
     /// <inheritdoc/>
     public AnsiRequestScheduler GetRequestScheduler () => _ansiRequestScheduler;

Terminal.Gui/Drivers/FakeDriver/FakeOutput.cs

@@ -19,6 +19,7 @@ public FakeOutput ()
     {
         LastBuffer = new OutputBufferImpl ();
         LastBuffer.SetSize (80, 25);
+        IsVirtualTerminal = true;
     }
 
     /// <summary>
@@ -86,10 +87,21 @@ public void Dispose ()
     /// <inheritdoc/>
     protected override void AppendOrWriteAttribute (StringBuilder output, Attribute attr, TextStyle redrawTextStyle)
     {
-        if (Application.Force16Colors)
+        if (Driver?.Force16Colors == true)
         {
-            output.Append (EscSeqUtils.CSI_SetForegroundColor (attr.Foreground.GetAnsiColorCode ()));
-            output.Append (EscSeqUtils.CSI_SetBackgroundColor (attr.Background.GetAnsiColorCode ()));
+            if (IsVirtualTerminal)
+            {
+                output.Append (EscSeqUtils.CSI_SetForegroundColor (attr.Foreground.GetAnsiColorCode ()));
+                output.Append (EscSeqUtils.CSI_SetBackgroundColor (attr.Background.GetAnsiColorCode ()));
+
+                EscSeqUtils.CSI_AppendTextStyleChange (output, redrawTextStyle, attr.Style);
+            }
+            else
+            {
+                Write (output);
+                Console.ForegroundColor = (ConsoleColor)attr.Foreground.GetClosestNamedColor16 ();
+                Console.BackgroundColor = (ConsoleColor)attr.Background.GetClosestNamedColor16 ();
+            }
         }
         else
         {
@@ -106,9 +118,9 @@ protected override void AppendOrWriteAttribute (StringBuilder output, Attribute
                                                       attr.Background.G,
                                                       attr.Background.B
                                                      );
-        }
 
-        EscSeqUtils.CSI_AppendTextStyleChange (output, redrawTextStyle, attr.Style);
+            EscSeqUtils.CSI_AppendTextStyleChange (output, redrawTextStyle, attr.Style);
+        }
     }
 
     /// <inheritdoc/>

Terminal.Gui/Drivers/IDriver.cs

@@ -100,6 +100,12 @@ public interface IDriver
     /// </remarks>
     bool Force16Colors { get; set; }
 
+    /// <summary>
+    ///     Collection of sixel images to write out to screen when updating.
+    ///     Only add to this collection if you are sure terminal supports sixel format.
+    /// </summary>
+    List<SixelToRender> Sixel { get; }
+
     /// <summary>
     ///     The <see cref="System.Attribute"/> that will be used for the next <see cref="AddRune(Rune)"/> or <see cref="AddStr"/>
     ///     call.

Terminal.Gui/Drivers/OutputBase.cs

@@ -5,6 +5,30 @@ namespace Terminal.Gui.Drivers;
 /// </summary>
 public abstract class OutputBase
 {
+    /// <summary>
+    /// Get or sets the <see cref="IDriver"/> instance associated with this output.
+    /// </summary>
+    internal IDriver? Driver { get; set; }
+
+    private bool _isVirtualTerminal;
+
+    /// <summary>
+    ///     Gets or sets whether <see cref="IDriver"/> support for virtualized terminal sequences.
+    /// </summary>
+    internal bool IsVirtualTerminal
+    {
+        get => _isVirtualTerminal;
+        set
+        {
+            _isVirtualTerminal = value;
+
+            if (Driver is DriverImpl driverImpl)
+            {
+                driverImpl.IsVirtualTerminal = _isVirtualTerminal;
+            }
+        }
+    }
+
     private CursorVisibility? _cachedCursorVisibility;
 
     // Last text style used, for updating style with EscSeqUtils.CSI_AppendTextStyleChange().
@@ -82,24 +106,32 @@ public virtual void Write (IOutputBuffer buffer)
 
             if (output.Length > 0)
             {
-                SetCursorPositionImpl (lastCol, row);
+                if (IsVirtualTerminal)
+                {
+                    SetCursorPositionImpl (lastCol, row);
 
-                // Wrap URLs with OSC 8 hyperlink sequences using the new Osc8UrlLinker
-                StringBuilder processed = Osc8UrlLinker.WrapOsc8 (output);
-                Write (processed);
+                    // Wrap URLs with OSC 8 hyperlink sequences using the new Osc8UrlLinker
+                    StringBuilder processed = Osc8UrlLinker.WrapOsc8 (output);
+                    Write (processed);
+                }
+                else
+                {
+                    Write (output);
+                }
             }
         }
 
-        // BUGBUG: The Sixel impl depends on the legacy static Application object
-        // BUGBUG: Disabled for now
-        //foreach (SixelToRender s in  Application.Sixel)
-        //{
-        //    if (!string.IsNullOrWhiteSpace (s.SixelData))
-        //    {
-        //        SetCursorPositionImpl (s.ScreenPosition.X, s.ScreenPosition.Y);
-        //        Console.Out.Write (s.SixelData);
-        //    }
-        //}
+        if (Driver is { } && IsVirtualTerminal)
+        {
+            foreach (SixelToRender s in Driver?.Sixel!)
+            {
+                if (!string.IsNullOrWhiteSpace (s.SixelData))
+                {
+                    SetCursorPositionImpl (s.ScreenPosition.X, s.ScreenPosition.Y);
+                    Write ((StringBuilder)new (s.SixelData));
+                }
+            }
+        }
 
         SetCursorVisibility (savedVisibility ?? CursorVisibility.Default);
         _cachedCursorVisibility = savedVisibility;
@@ -230,9 +262,16 @@ private void WriteToConsole (StringBuilder output, ref int lastCol, int row, ref
     {
         SetCursorPositionImpl (lastCol, row);
 
-        // Wrap URLs with OSC 8 hyperlink sequences using the new Osc8UrlLinker
-        StringBuilder processed = Osc8UrlLinker.WrapOsc8 (output);
-        Write (processed);
+        if (IsVirtualTerminal)
+        {
+            // Wrap URLs with OSC 8 hyperlink sequences using the new Osc8UrlLinker
+            StringBuilder processed = Osc8UrlLinker.WrapOsc8 (output);
+            Write (processed);
+        }
+        else
+        {
+            Write (output);
+        }
 
         output.Clear ();
         lastCol += outputWidth;

Terminal.Gui/Drivers/UnixDriver/UnixOutput.cs

@@ -36,10 +36,15 @@ private struct WinSize
     [DllImport ("libc", SetLastError = true)]
     private static extern int dup (int fd);
 
+    public UnixOutput ()
+    {
+        IsVirtualTerminal = true;
+    }
+
     /// <inheritdoc />
     protected override void AppendOrWriteAttribute (StringBuilder output, Attribute attr, TextStyle redrawTextStyle)
     {
-        if (Application.Force16Colors)
+        if (Driver?.Force16Colors == true)
         {
             output.Append (EscSeqUtils.CSI_SetForegroundColor (attr.Foreground.GetAnsiColorCode ()));
             output.Append (EscSeqUtils.CSI_SetBackgroundColor (attr.Background.GetAnsiColorCode ()));