/**
 *  License (BSD Style License):
 *   Copyright (c) 2011
 *   Software Engineering
 *   Department of Computer Science
 *   Technische Universität Darmstadt
 *   All rights reserved.
 * 
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions are met:
 * 
 *   - Redistributions of source code must retain the above copyright notice,
 *     this list of conditions and the following disclaimer.
 *   - Redistributions in binary form must reproduce the above copyright notice,
 *     this list of conditions and the following disclaimer in the documentation
 *     and/or other materials provided with the distribution.
 *   - Neither the name of the Software Engineering Group or Technische 
 *     Universität Darmstadt nor the names of its contributors may be used to 
 *     endorse or promote products derived from this software without specific 
 *     prior written permission.
 * 
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 *   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *   POSSIBILITY OF SUCH DAMAGE.
 */
package de.tud.cs.st.vespucci.diagram.menuItems;

import org.eclipse.core.expressions.PropertyTester;
import org.eclipse.gmf.runtime.diagram.ui.editparts.ConnectionEditPart;

import de.tud.cs.st.vespucci.vespucci_model.Connection;
import de.tud.cs.st.vespucci.vespucci_model.Dummy;
import de.tud.cs.st.vespucci.vespucci_model.Shape;

/**
 * PropertyTester to check whether a connection starts or ends at an Empty Ensemble.
 * 
 * @author Dominic Scheurer
 */
public class ConnectionPointsToDummyTester extends PropertyTester {

	@Override
	public boolean test(final Object receiver, final String property, final Object[] args, final Object expectedValue) {
		final ConnectionEditPart connectionEditPart = (ConnectionEditPart) receiver;
		final Connection connection = (Connection) connectionEditPart.resolveSemanticElement();

		return (getOriginalSource(connection) instanceof Dummy) || (getOriginalTarget(connection) instanceof Dummy);
	}

	// XXX: This method should be part of the Connection interface.
	private static Shape getOriginalSource(final Connection conn) {
		if (conn.getOriginalSource().isEmpty()) {
			return conn.getSource();
		} else {
			return conn.getOriginalSource().get(0);
		}
	}

	// XXX: This method should be part of the Connection interface
	private static Shape getOriginalTarget(final Connection conn) {
		if (conn.getOriginalTarget().isEmpty()) {
			return conn.getTarget();
		} else {
			return conn.getOriginalTarget().get(0);
		}
	}

}