Unlimited undo/redo for Fl_Input_ and Fl_Text_Buffer (#558) (#676)

4 files changed, 26 insertions, 3 deletions

diff --git a/FL/Fl_Input.H b/FL/Fl_Input.H
index 93d1c2642..f53debd50 100644
--- a/FL/Fl_Input.H
+++ b/FL/Fl_Input.H
@@ -1,7 +1,7 @@
 //
 // Input header file for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2021 by Bill Spitzak and others.
+// Copyright 1998-2023 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/FL/Fl_Input_.H b/FL/Fl_Input_.H
index d89a341bc..a7062f5a0 100644
--- a/FL/Fl_Input_.H
+++ b/FL/Fl_Input_.H
@@ -39,6 +39,7 @@
 #define FL_MULTILINE_OUTPUT_WRAP (FL_MULTILINE_INPUT | FL_INPUT_READONLY | FL_INPUT_WRAP)
 
 class Fl_Input_Undo_Action;
+class Fl_Input_Undo_Action_List;
 
 /**
   This class provides a low-overhead text input field.
@@ -148,6 +149,8 @@ class FL_EXPORT Fl_Input_ : public Fl_Widget {
 
   /** \internal local undo event */
   Fl_Input_Undo_Action* undo_;
+  Fl_Input_Undo_Action_List* undo_list_;
+  Fl_Input_Undo_Action_List* redo_list_;
 
   /** \internal Horizontal cursor position in pixels while moving up or down. */
   static double up_down_pos;
@@ -212,6 +215,9 @@ protected:
   /* Return the number of lines displayed on a single page.  */
   int linesPerPage();
 
+  /* Apply the current undo/redo operation, called from undo() or redo() */
+  int apply_undo();
+
 public:
 
   /* Change the size of the widget. */
@@ -378,6 +384,9 @@ public:
   /* Undo previous changes to the text buffer. */
   int undo();
 
+  /* Redo previous undo operations. */
+  int redo();
+
   /* Copy the yank buffer to the clipboard. */
   int copy_cuts();
 
diff --git a/FL/Fl_Text_Buffer.H b/FL/Fl_Text_Buffer.H
index e3e131ef1..dabe5677a 100644
--- a/FL/Fl_Text_Buffer.H
+++ b/FL/Fl_Text_Buffer.H
@@ -1,7 +1,7 @@
 //
 // Header file for Fl_Text_Buffer class.
 //
-// Copyright 2001-2021 by Bill Spitzak and others.
+// Copyright 2001-2023 by Bill Spitzak and others.
 // Original code Copyright Mark Edel.  Permission to distribute under
 // the LGPL for the FLTK library granted by Mark Edel.
 //
@@ -61,6 +61,7 @@
 
 #include "Fl_Export.H"
 
+class Fl_Text_Undo_Action_List;
 class Fl_Text_Undo_Action;
 
 /**
@@ -327,6 +328,11 @@ public:
   int undo(int *cp=0);
 
   /**
+   Redo previous undo action.
+   */
+  int redo(int *cp=0);
+
+  /**
    Lets the undo system know if we can undo changes
    */
   void canUndo(char flag=1);
@@ -813,6 +819,11 @@ protected:
    */
   void update_selections(int pos, int nDeleted, int nInserted);
 
+  /**
+   Apply the current undo/redo operation, called from undo() or redo().
+   */
+  int apply_undo(Fl_Text_Undo_Action* action, int* cursorPos);
+
   Fl_Text_Selection mPrimary;     /**< highlighted areas */
   Fl_Text_Selection mSecondary;   /**< highlighted areas */
   Fl_Text_Selection mHighlight;   /**< highlighted areas */
@@ -841,6 +852,8 @@ protected:
                                        bytes and should only be increased if frequent
                                        and large changes in buffer size are expected */
   Fl_Text_Undo_Action* mUndo;     /**< local undo event */
+  Fl_Text_Undo_Action_List* mUndoList; /**< List of undo event */
+  Fl_Text_Undo_Action_List* mRedoList; /**< List of redo event */
 };
 
 #endif
diff --git a/FL/Fl_Text_Editor.H b/FL/Fl_Text_Editor.H
index 5bf49781e..16af25451 100644
--- a/FL/Fl_Text_Editor.H
+++ b/FL/Fl_Text_Editor.H
@@ -1,7 +1,7 @@
 //
 // Header file for Fl_Text_Editor class.
 //
-// Copyright 2001-2010 by Bill Spitzak and others.
+// Copyright 2001-2023 by Bill Spitzak and others.
 // Original code Copyright Mark Edel.  Permission to distribute under
 // the LGPL for the FLTK library granted by Mark Edel.
 //
@@ -110,6 +110,7 @@ class FL_EXPORT Fl_Text_Editor : public Fl_Text_Display {
     static int kf_paste(int c, Fl_Text_Editor* e);
     static int kf_select_all(int c, Fl_Text_Editor* e);
     static int kf_undo(int c, Fl_Text_Editor* e);
+    static int kf_redo(int c, Fl_Text_Editor* e);
 
   protected:
     int handle_key();