// -*- C++ -*-
-/* This file is part of
- * ======================================================
- *
- * LyX, The Document Processor
- *
- * Copyright (C) 1995 Matthias Ettrich, 1995, 1996 LyX Team
+/**
+ * \file undo.h
+ * This file is part of LyX, the document processor.
+ * Licence details can be found in the file COPYING.
*
- *======================================================*/
-#ifndef _UNDO_H
-#define _UNDO_H
+ * \author Asger Alstrup
+ * \author Lars Gullik Bjønnes
+ * \author John Levon
+ * \author André Pönitz
+ * \author Jürgen Vigna
+ *
+ * Full author contact details are available in file CREDITS.
+ */
-#ifdef __GNUG__
-#pragma interface
-#endif
+#ifndef UNDO_H
+#define UNDO_H
-#include "definitions.h"
-#include "lyxparagraph.h"
+#include "ParagraphList_fwd.h"
+#include "support/types.h"
+class LyXText;
+class BufferView;
-///
+/**
+ * These are the elements put on the undo stack. Each object
+ * contains complete paragraphs and sufficient information
+ * to restore the state.
+ */
class Undo {
public:
- /// The undo kinds
+ /**
+ * The undo kinds are used to combine consecutive undo recordings
+ * of the same kind.
+ */
enum undo_kind {
- ///
+ /**
+ * Insert something - these will combine to one big chunk
+ * when many inserts come after each other.
+ */
INSERT,
- ///
+
+ /**
+ * Delete something - these will combine to one big chunk
+ * when many deletes come after each other.
+ */
DELETE,
- ///
- EDIT,
- ///
- FINISH
+
+ /// Atomic - each of these will have its own entry in the stack
+ ATOMIC
};
- ///
+ /// constructor
+ Undo(undo_kind kind, int text, int index,
+ int first_par, int end_par, int cursor_par, int cursor_pos);
+
+ /// which kind of operation are we recording for?
undo_kind kind;
- ///
- int number_of_before_par;
- ///
- int number_of_behind_par;
- ///
- int number_of_cursor_par;
- ///
- int cursor_pos; // valid if >= 0
- ///
- LyXParagraph* par;
- ///
- Undo(undo_kind kind_arg,
- int number_before_arg, int number_behind_arg,
- int cursor_par_arg, int cursor_pos_arg,
- LyXParagraph* par_arg)
- {
- kind = kind_arg;
- number_of_before_par = number_before_arg;
- number_of_behind_par = number_behind_arg;
- number_of_cursor_par = cursor_par_arg;
- cursor_pos = cursor_pos_arg;
- par = par_arg;
- }
- ///
- ~Undo(){
- LyXParagraph* tmppar;
- while (par) {
- tmppar = par;
- par = par->next;
- delete tmppar;
- }
- }
-};
+ /// hosting LyXText counted from buffer begin
+ int text;
-/// A limited Stack for the undo informations. Matthias 290496
-class UndoStack{
-private:
- ///
- struct StackAtom{
- ///
- StackAtom* previous;
- ///
- Undo* undo;
- };
- ///
- StackAtom* current;
- ///
- StackAtom *tmp;
- ///
- int size;
- ///
- int limit;
-public:
- ///
- UndoStack(){
- current = NULL;
- // size must be initialised (thornley)
- size = 0;
- limit = 100; // the maximum number of undo steps stored. 0 means NO LIMIT.
- // Limit can be changed with UndoStack::SetStackLimit(int)
- }
- ///
- Undo *Pop(){
- Undo* result = NULL;
- if (current){
- result = current->undo;
- tmp = current;
- current = current->previous;
- delete tmp;
- size--;
- }
- else {
- size = 0; // for safety...
- }
- return result;
- }
- ///
- Undo* Top(){
- if (current)
- return current->undo;
- else
- return NULL;
- }
- ///
- ~UndoStack(){
- Clear();
- }
- ///
- void Clear(){
- Undo* tmp_undo = Pop();
- while (tmp_undo){
- delete tmp_undo;
- tmp_undo = Pop();
- }
- }
- ///
- void SetStackLimit(int limit_arg) {
- limit = limit_arg;
- }
-
- ///
- void Push(Undo* undo_arg){
- int i;
- StackAtom* tmp2;
- if (undo_arg){
- tmp = new StackAtom;
- tmp->undo = undo_arg;
- tmp->previous = current;
- current = tmp;
- size++;
- if (limit && size > limit){
- for (i=0; i<limit && tmp; i++)
- tmp = tmp->previous;
- while(tmp && tmp->previous){
- tmp2 = tmp->previous->previous;
- delete tmp->previous;
- size--;
- tmp->previous = tmp2;
- }
- }
- }
- }
+ /// cell in a tabular or similar
+ int index;
+
+ /// offset to the first paragraph in the paragraph list
+ int first_par;
+
+ /// offset to the last paragraph from the end of parargraph list
+ int end_par;
+
+ /// offset to the first paragraph in the paragraph list
+ int cursor_par;
+
+ /// the position of the cursor in the hosting paragraph
+ int cursor_pos;
+
+ /// the contents of the paragraphs saved
+ ParagraphList pars;
};
-#endif
+
+/// this will undo the last action - returns false if no undo possible
+bool textUndo(BufferView *);
+
+/// this will redo the last undo - returns false if no redo possible
+bool textRedo(BufferView *);
+
+/// makes sure the next operation will be stored
+void finishUndo();
+
+/// whilst undo is frozen, all actions do not get added to the undo stack
+void freezeUndo();
+
+/// track undos again
+void unFreezeUndo();
+
+/**
+ * Record undo information - call with the first paragraph that will be changed
+ * and the last paragraph that will be changed. So we give an inclusive
+ * range.
+ * This is called before you make the changes to the paragraph, and it
+ * will record the original information of the paragraphs in the undo stack.
+ */
+void recordUndo(Undo::undo_kind kind,
+ LyXText const * text, lyx::paroffset_type first, lyx::paroffset_type last);
+
+/// convienience: prepare undo when change in a single paragraph
+void recordUndo(Undo::undo_kind kind,
+ LyXText const * text, lyx::paroffset_type par);
+
+/// convienience: prepare undo for the paragraph that contains the cursor
+void recordUndo(BufferView *, Undo::undo_kind kind);
+
+/// are we avoiding tracking undos currently?
+extern bool undo_frozen;
+
+#endif // UNDO_FUNCS_H