add missing modes

Author: tomlm

src/XTerm.NET/Common/CommandExtensions.cs

@@ -29,6 +29,7 @@ public static class CsiCommandExtensions
         { "c", CsiCommand.DeviceAttributes },
         { "d", CsiCommand.LinePositionAbsolute },
         { "f", CsiCommand.CursorPosition }, // HVP - same as CUP
+        { "g", CsiCommand.TabClear },
         { "h", CsiCommand.SetMode },
         { "l", CsiCommand.ResetMode },
         { "m", CsiCommand.SelectGraphicRendition },

src/XTerm.NET/Common/CsiCommand.cs

@@ -102,6 +102,13 @@ public enum CsiCommand
     /// </summary>
     CursorBackwardTab,
 
+    /// <summary>
+    /// Tab Clear (CSI g).
+    /// Ps = 0: Clear current column tab stop.
+    /// Ps = 3: Clear all tab stops.
+    /// </summary>
+    TabClear,
+    
     /// <summary>
     /// Device Attributes (CSI c).
     /// </summary>

src/XTerm.NET/Common/TerminalMode.cs

@@ -38,6 +38,12 @@ public enum TerminalMode
     /// </summary>
     SmoothScroll = 4,
 
+    /// <summary>
+    /// Reverse Video (DECSCNM).
+    /// When set, the entire screen is displayed in reverse video.
+    /// </summary>
+    ReverseVideo = 5,
+    
     /// <summary>
     /// Origin Mode (DECOM).
     /// </summary>
@@ -58,6 +64,18 @@ public enum TerminalMode
     /// </summary>
     ShowCursor = 25,
 
+    /// <summary>
+    /// National Replacement Character Set Mode (DECNRCM).
+    /// When set, enables national replacement character sets.
+    /// </summary>
+    NationalCharset = 42,
+    
+    /// <summary>
+    /// Reverse Wraparound Mode.
+    /// When set, allows backspace to wrap from column 0 to the previous line.
+    /// </summary>
+    ReverseWraparound = 45,
+    
     /// <summary>
     /// Application Keypad (DECNKM).
     /// </summary>

src/XTerm.NET/InputHandler.cs

@@ -416,6 +416,10 @@ public void HandleCsi(string identifier, Params parameters)
                 CursorBackwardTab(parameters);
                 break;
 
+            case CsiCommand.TabClear:
+                TabClear(parameters);
+                break;
+
             case CsiCommand.DeviceAttributes:
                 DeviceAttributes(parameters, isPrivate);
                 break;
@@ -1065,6 +1069,25 @@ private void CursorBackwardTab(Params parameters)
         }
     }
 
+    private void TabClear(Params parameters)
+    {
+        // TBC - Tab Clear (CSI g)
+        // Ps = 0: Clear tab stop at current column (default)
+        // Ps = 3: Clear all tab stops
+        // Note: We use fixed tab stops, so this is acknowledged but has no effect
+        // A full implementation would maintain a list of custom tab stops
+        var mode = parameters.GetParam(0, 0);
+        switch (mode)
+        {
+            case 0:
+                // Clear current column tab stop - acknowledged but no action
+                break;
+            case 3:
+                // Clear all tab stops - acknowledged but no action
+                break;
+        }
+    }
+
     private void DeviceAttributes(Params parameters, bool isPrivate)
     {
         // DA - Device Attributes (CSI c or CSI > c)
@@ -1519,19 +1542,45 @@ private void SetModeInternal(int mode, bool isPrivate)
                     _terminal.ApplicationCursorKeys = true;
                     break;
 
+                case TerminalMode.InsertMode:
+                    // Mode 4: In DEC private mode context, this is SmoothScroll (DECSCLM)
+                    // InsertMode and SmoothScroll share value 4 in the enum
+                    // Smooth scroll is acknowledged but has no effect in modern terminals
+                    break;
+
+                case TerminalMode.ReverseVideo:
+                    _terminal.ReverseVideo = true;
+                    break;
+
                 case TerminalMode.Origin:
                     _terminal.OriginMode = true;
                     _buffer.SetCursor(0, 0);
                     break;
 
                 case TerminalMode.Wraparound:
+                    // Mode 7: Wraparound mode
+                    // Wraparound and AutoWrapMode share value 7 in the enum
                     _terminal.Options.Wraparound = true;
                     break;
 
+                case TerminalMode.AutoRepeat:
+                    // Auto repeat is typically always enabled in modern terminals
+                    // This mode is acknowledged but has no effect
+                    break;
+
                 case TerminalMode.ShowCursor:
                     _terminal.CursorVisible = true;
                     break;
 
+                case TerminalMode.NationalCharset:
+                    // National replacement character set mode
+                    // Acknowledged but typically no specific action needed for modern use
+                    break;
+
+                case TerminalMode.ReverseWraparound:
+                    _terminal.ReverseWraparound = true;
+                    break;
+
                 case TerminalMode.AppKeypad:
                     _terminal.ApplicationKeypad = true;
                     break;
@@ -1683,19 +1732,43 @@ private void ResetModeInternal(int mode, bool isPrivate)
                     _terminal.ApplicationCursorKeys = false;
                     break;
 
+                case TerminalMode.InsertMode:
+                    // Mode 4: In DEC private mode context, this is SmoothScroll (DECSCLM)
+                    // Smooth scroll is acknowledged but has no effect in modern terminals
+                    break;
+
+                case TerminalMode.ReverseVideo:
+                    _terminal.ReverseVideo = false;
+                    break;
+
                 case TerminalMode.Origin:
                     _terminal.OriginMode = false;
                     _buffer.SetCursor(0, 0);
                     break;
 
                 case TerminalMode.Wraparound:
+                    // Mode 7: Wraparound mode
                     _terminal.Options.Wraparound = false;
                     break;
 
+                case TerminalMode.AutoRepeat:
+                    // Auto repeat is typically always enabled in modern terminals
+                    // This mode is acknowledged but has no effect
+                    break;
+
                 case TerminalMode.ShowCursor:
                     _terminal.CursorVisible = false;
                     break;
 
+                case TerminalMode.NationalCharset:
+                    // National replacement character set mode
+                    // Acknowledged but typically no specific action needed for modern use
+                    break;
+
+                case TerminalMode.ReverseWraparound:
+                    _terminal.ReverseWraparound = false;
+                    break;
+
                 case TerminalMode.AppKeypad:
                     _terminal.ApplicationKeypad = false;
                     break;

src/XTerm.NET/Terminal.cs

@@ -38,6 +38,7 @@ public class Terminal
     public bool OriginMode { get; set; }
     public bool CursorVisible { get; set; }
     public bool ReverseWraparound { get; set; }
+    public bool ReverseVideo { get; set; }
     public bool SendFocusEvents { get; set; }
     public bool Win32InputMode { get; set; }
 
@@ -305,6 +306,7 @@ public void Reset()
         OriginMode = false;
         CursorVisible = true;
         ReverseWraparound = false;
+        ReverseVideo = false;
         SendFocusEvents = false;
         EightBitInput = false;
         MetaSendsEscape = false;  // Default is disabled