/*
 * This file is part of ***  M y C o R e  ***
 * See http://www.mycore.de/ for details.
 *
 * MyCoRe is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * MyCoRe is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with MyCoRe.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.mycore.frontend.xeditor.tracker;

import org.jdom2.Content;
import org.jdom2.Element;

public class MCRSwapElements implements MCRChange {

    public static MCRChangeData swap(Element parent, Element a, Element b) {
        int posA = parent.indexOf(a);
        int posB = parent.indexOf(b);
        return swap(parent, posA, a, posB, b);
    }

    public static MCRChangeData swap(Element parent, int posA, int posB) {
        Content a = parent.getContent().get(posA);
        Content b = parent.getContent().get(posB);
        return swap(parent, posA, a, posB, b);
    }

    public static MCRChangeData swap(Element parent, int posA, Content a, int posB, Content b) {
        if (posA > posB) {
            return swap(parent, posB, b, posA, a);
        }

        b.detach(); // x a x x x  
        parent.addContent(posA, b); // x b a x x x 
        a.detach(); // x b x x x
        parent.addContent(posB, a); // x b x x a x

        return new MCRChangeData("swapped-elements", posA + " " + posB, posB, parent);
    }

    public void undo(MCRChangeData data) {
        int posA = Integer.parseInt(data.getText().split(" ")[0]);
        int posB = Integer.parseInt(data.getText().split(" ")[1]);
        swap(data.getContext(), posA, posB);
    }
}
