/*******************************************************************************
 * Copyright (c) 2004-2008 Istvan Rath and Daniel Varro
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Istvan Rath - initial API and implementation
 *******************************************************************************/

 package org.eclipse.viatra2.treeeditor.providers;


import java.text.Collator;

import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerSorter;
import org.eclipse.viatra2.core.IModelElement;

public class ViatraTreeviewSorter extends ViewerSorter {

	public ViatraTreeviewSorter() {
		super();
	}

	public ViatraTreeviewSorter(Collator collator) {
		super(collator);
	}
	
	@Override
	public int compare(Viewer viewer, Object arg0, Object arg1) {
		if (arg0 instanceof IModelElement && arg1 instanceof IModelElement)
		{
			IModelElement a0 = (IModelElement) arg0;
			IModelElement a1 = (IModelElement) arg1;
			if (a0.getClass().equals(a1.getClass()))
				return (a0.getName().compareTo(a1.getName()));
			else if (a0.isEntity() && a1.isRelation())
				return +1;
			else
				return -1;
		}
		else if (arg0 instanceof IModelElement) return -1;
		else if (arg1 instanceof IModelElement) return +1;
		return 0;
	}

}