added undo/redo to EditableWidget

src/common/EventHandlerSDL2.cxx

@@ -27,6 +27,15 @@ EventHandlerSDL2::EventHandlerSDL2(OSystem& osystem)
 {
   ASSERT_MAIN_THREAD;
 
+#ifdef GUI_SUPPORT
+  {
+    ostringstream buf;
+    myQwertz = int('y') == int(SDL_GetKeyFromScancode(SDL_Scancode(KBDK_Z)));
+    buf << "Keyboard: " << (myQwertz ? "QWERTZ" : "QWERTY");
+    Logger::debug(buf.str());
+  }
+#endif
+
 #ifdef JOYSTICK_SUPPORT
   if(SDL_InitSubSystem(SDL_INIT_JOYSTICK) < 0)
   {

src/emucore/EventHandler.hxx

@@ -338,6 +338,11 @@ class EventHandler
     virtual void enableTextEvents(bool enable) = 0;
 
   #ifdef GUI_SUPPORT
+    /**
+      Check for QWERTZ keyboard layout
+    */
+    bool isQwertz() { return myQwertz; }
+
     /**
       Clipboard methods.
     */
@@ -359,6 +364,11 @@ class EventHandler
     // Global OSystem object
     OSystem& myOSystem;
 
+  #ifdef GUI_SUPPORT
+    // Keyboard layout
+    bool myQwertz{false};
+  #endif
+
     /**
       Methods which are called by derived classes to handle specific types
       of input.

src/gui/EditableWidget.cxx

@@ -47,6 +47,9 @@ void EditableWidget::setText(const string& str, bool)
     if(_filter(tolower(c)))
       _editString.push_back(c);
 
+  clearEdits();
+  doEdit();
+
   _caretPos = int(_editString.size());
   _selectSize = 0;
 
@@ -78,12 +81,64 @@ void EditableWidget::lostFocusWidget()
   _selectSize = 0;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void EditableWidget::clearEdits()
+{
+  _editBuffer.clear();
+  _redoCount = 0;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+void EditableWidget::doEdit()
+{
+  constexpr size_t UNDO_SIZE = 100;
+
+  // clear redos
+  for(; _redoCount; _redoCount--)
+    _editBuffer.pop_back();
+
+  if(_editBuffer.size() == UNDO_SIZE)
+    _editBuffer.pop_front();
+  _editBuffer.push_back(_editString);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool EditableWidget::undoEdit()
+{
+  if(_editBuffer.size() - _redoCount - 1)
+  {
+    _redoCount++;
+    _editString = _editBuffer[_editBuffer.size() - _redoCount - 1];
+    _caretPos = int(_editString.size()); // TODO: put at last difference
+    _selectSize = 0;
+
+    return true;
+  }
+  return false;
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+bool EditableWidget::redoEdit()
+{
+  if(_redoCount)
+  {
+    _redoCount--;
+    _editString = _editBuffer[_editBuffer.size() - _redoCount - 1];
+    _caretPos = int(_editString.size()); // TODO: put at last difference
+    _selectSize = 0;
+
+    return true;
+  }
+  return false;
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool EditableWidget::tryInsertChar(char c, int pos)
 {
   if(_filter(tolower(c)))
   {
     _editString.insert(pos, 1, c);
+    doEdit();
     return true;
   }
   return false;
@@ -187,8 +242,12 @@ bool EditableWidget::handleControlKeys(StellaKey key, StellaMod mod)
         sendCommand(EditableWidget::kChangedCmd, key, _id);
       break;
 
+    case KBDK_Y:
     case KBDK_Z:
-      // TODO: undo
+      if(key == KBDK_Y != instance().eventHandler().isQwertz())
+        dirty = redoEdit();
+      else
+        dirty = undoEdit();
       break;
 
     case KBDK_LEFT:
@@ -469,7 +528,7 @@ int EditableWidget::scrollOffset()
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-bool EditableWidget::killChar(int direction)
+bool EditableWidget::killChar(int direction, bool addEdit)
 {
   bool handled = false;
 
@@ -480,12 +539,20 @@ bool EditableWidget::killChar(int direction)
       _caretPos--;
       _editString.erase(_caretPos, 1);
       handled = true;
+      if(_selectSize < 0)
+        _selectSize++;
+      if(addEdit)
+        doEdit();
     }
   }
   else if(direction == 1)  // Delete next character (delete)
   {
     _editString.erase(_caretPos, 1);
     handled = true;
+    if(_selectSize > 0)
+      _selectSize--;
+    if(addEdit)
+      doEdit();
   }
 
   return handled;
@@ -502,12 +569,13 @@ bool EditableWidget::killLine(int direction)
     if(count > 0)
     {
       for (int i = 0; i < count; i++)
-        killChar(-1);
+        killChar(-1, false);
 
       handled = true;
       // remove selection for removed text
       if(_selectSize < 0)
         _selectSize = 0;
+      doEdit();
     }
   }
   else if(direction == 1)  // erase from current position to end of line
@@ -516,12 +584,13 @@ bool EditableWidget::killLine(int direction)
     if(count > 0)
     {
       for (int i = 0; i < count; i++)
-        killChar(+1);
+        killChar(+1, false);
 
       handled = true;
       // remove selection for removed text
       if(_selectSize > 0)
         _selectSize = 0;
+      doEdit();
     }
   }
 
@@ -551,12 +620,13 @@ bool EditableWidget::killLastWord()
   if(count > 0)
   {
     for (int i = 0; i < count; i++)
-      killChar(-1);
+      killChar(-1, false);
 
     handled = true;
     // remove selection for removed word
     if(_selectSize < 0)
       _selectSize = std::min(_selectSize + count, 0);
+    doEdit();
   }
 
   return handled;
@@ -649,7 +719,7 @@ int EditableWidget::selectEndPos()
 
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-bool EditableWidget::killSelectedText()
+bool EditableWidget::killSelectedText(bool addEdit)
 {
   if(_selectSize)
   {
@@ -660,6 +730,8 @@ bool EditableWidget::killSelectedText()
     }
     _editString.erase(_caretPos, _selectSize);
     _selectSize = 0;
+    if(addEdit)
+      doEdit();
     return true;
   }
   return false;
@@ -703,7 +775,7 @@ bool EditableWidget::pasteSelectedText()
   // retrieve the pasted text
   instance().eventHandler().pasteText(pasted);
   // remove the currently selected text
-  killSelectedText();
+  killSelectedText(false);
   // insert filtered paste text instead
   ostringstream buf;
   bool lastOk = true; // only one filler char per invalid character (block)
@@ -725,5 +797,10 @@ bool EditableWidget::pasteSelectedText()
   // position cursor at the end of pasted text
   _caretPos += int(buf.str().length());
 
-  return selected || !pasted.empty();
+  if(selected || !pasted.empty())
+  {
+    doEdit();
+    return true;
+  }
+  return false;
 }

src/gui/EditableWidget.hxx

@@ -19,6 +19,7 @@
 #define EDITABLE_WIDGET_HXX
 
 #include <functional>
+#include <deque>
 
 #include "Widget.hxx"
 #include "Rect.hxx"
@@ -89,18 +90,23 @@ class EditableWidget : public Widget, public CommandSender
     bool handleControlKeys(StellaKey key, StellaMod mod);
     bool handleShiftKeys(StellaKey key);
     bool handleNormalKeys(StellaKey key);
-    bool killChar(int direction);
+    bool killChar(int direction, bool addEdit = true);
     bool killLine(int direction);
     bool killLastWord();
     bool moveWord(int direction, bool select);
 
-    bool killSelectedText();
+    bool killSelectedText(bool addEdit = true);
     int selectStartPos();
     int selectEndPos();
     // Clipboard
     bool cutSelectedText();
     bool copySelectedText();
     bool pasteSelectedText();
+    // Undo
+    void clearEdits();
+    void doEdit();
+    bool undoEdit();
+    bool redoEdit();
 
     // Use the current TextFilter to insert a character into the
     // internal buffer
@@ -109,6 +115,9 @@ class EditableWidget : public Widget, public CommandSender
   private:
     bool   _editable{true};
     string _editString;
+
+    std::deque<string> _editBuffer;
+    int    _redoCount{0};
     int    _caretPos{0};
     // Size of current selected text
     //    0 = no selection