/*!
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This program 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 Lesser General Public License for more details.
*
* Copyright (c) 2002-2013 Pentaho Corporation..  All rights reserved.
*/

package org.pentaho.reporting.designer.core.util.undo;

import org.pentaho.reporting.designer.core.editor.ReportDocumentContext;
import org.pentaho.reporting.designer.core.model.ModelUtility;
import org.pentaho.reporting.engine.classic.core.Element;
import org.pentaho.reporting.engine.classic.core.Section;
import org.pentaho.reporting.engine.classic.core.util.InstanceID;

/**
 * Handles insert, remove and replacement of elements. Insert: old is null, remove: new is null.
 *
 * @author Thomas Morgner
 */
public class SectionEditUndoEntry implements UndoEntry {
  private InstanceID target;
  private int position;
  private Element oldElement;
  private Element newElement;

  public SectionEditUndoEntry( final InstanceID target,
                               final int position,
                               final Element oldElement,
                               final Element newElement ) {
    this.target = target;
    this.position = position;
    this.oldElement = oldElement;
    this.newElement = newElement;
  }

  public void undo( final ReportDocumentContext renderContext ) {
    final Section elementById = (Section)
      ModelUtility.findElementById( renderContext.getReportDefinition(), target );
    elementById.setElementAt( position, oldElement );
  }

  public void redo( final ReportDocumentContext renderContext ) {
    final Section elementById = (Section)
      ModelUtility.findElementById( renderContext.getReportDefinition(), target );
    elementById.setElementAt( position, newElement );
  }

  public UndoEntry merge( final UndoEntry newEntry ) {
    return null;
  }
}