UndoRedo.cpp

#include "UndoRedo.h"

UndoRedo::UndoRedo(){
    l = new undoredolist;
    l->next = NULL;
    l->prev = l;
    l->element = new Track();
    c = l;
    keepbeforeundo = 1;
}
UndoRedo::~UndoRedo(){
    del_list(l);
}
void UndoRedo::add(Track* element){
    if(element->notNULL()){
        del_list(c->next);
        c->next = new undoredolist;
        c->next->prev = c;
        c = c->next;
        c->next = NULL;
        c->element = new Track(element);
        l->prev = c;
        keepbeforeundo = 1;
    }
}
Track* UndoRedo::undo(Track* element){
    if(keepbeforeundo){
        /*bevor etwas rueckgaengig gemacht wird sollte der aktuellste Zustand
        eventuell gesichert werden*/
        add(element);
        keepbeforeundo = 0;
    }
    else
        /*oder eben geloescht*/
        element->~Track();
    if(c != l){
        c = c->prev;
        return new Track(c->element);
    }
    else
        return new Track(l->element);
}
Track* UndoRedo::redo(){
    if(c->next != NULL){
        c = c->next;
        return new Track(c->element);
    }
    else
        return new Track(c->element);
}
void UndoRedo::del_list(undoredolist* t){
    undoredolist* tt;
    while(t != NULL){
        tt = t;
        t = t->next;
        tt->element->~Track();
        delete tt;
    }
}