Added the beginnings of a class to represent an undo list.

git-svn-id: http://openexile.googlecode.com/svn/trunk@82 4ebdad44-0ea0-11de-aab3-ff745001d230

osx/tools/undo.h

@@ -0,0 +1,45 @@
+/*
+ *  undo.h
+ *  BoE
+ *
+ *  Created by Celtic Minstrel on 29/05/09.
+ *
+ *  For use in creating an undo history in the scenario editor.
+ *  Could also be used in the PC editor.
+ *
+ */
+
+#include <list>
+
+class cAction {
+public:
+	virtual void undo() = 0; // undoes this action if it has not already been undone
+	virtual void redo() = 0; // redoes this action if it has been undone
+	virtual bool isDone() = 0; // checks to see whether the action has been undone; returns false if it has
+	virtual std::string getActionName() = 0; // returns the name of this action for display in the Edit menu
+	virtual ~cAction();
+};
+
+class cUndoList {
+	std::list<cAction*> theList;
+	std::list<cAction*>::iterator cur, lastSave;
+	size_t num_actions;
+public:
+	cUndoList();
+	void undo(); // undoes the current action and decrements the cur pointer
+	void redo(); // increments the cur pointer and redoes the current action
+	void save(); // sets the last saved action to the current action
+	void revert(); // undoes all actions back to (but excluding) the last saved action
+	void add(cAction* what);
+	static size_t maxUndoSize;
+};
+
+// As a special convention, I will prefix action classes with 'a' instead of 'c'
+/*
+class aEditMonster : public cAction {
+	cMonster oldMonst, newMonst;
+};
+
+class aEditItem : public cAction {
+	cItemRec oldItem, newItem;
+};*/