/*******************************************************************************
 * <copyright>
 *
 * Copyright (c) 2005, 2012 SAP AG.
 * 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:
 *    SAP AG - initial API, implementation and documentation
 *
 * </copyright>
 *
 *******************************************************************************/
package org.eclipse.graphiti.ui.internal.policy;

import org.eclipse.gef.EditPart;
import org.eclipse.gef.EditPolicy;
import org.eclipse.gef.Request;
import org.eclipse.gef.commands.Command;
import org.eclipse.gef.editpolicies.LayoutEditPolicy;
import org.eclipse.gef.requests.CreateRequest;
import org.eclipse.graphiti.ui.platform.IConfigurationProvider;

/**
 * An EditPolicy, which 'forbids' any Layout dependent Commands. All methods of
 * this EditPolicy return null, which is different from using no EditPolicy at
 * all, because it will create a visible feedback that the requests are
 * forbidden. This EditPolicy can for example be used for those EditParts, which
 * do not have any children.
 * 
 * @see org.eclipse.graphiti.ui.internal.policy.IEditPolicyFactory#createShapeForbidLayoutEditPolicy()
 * @noinstantiate This class is not intended to be instantiated by clients.
 * @noextend This class is not intended to be subclassed by clients.
 */
public class ShapeForbidLayoutEditPolicy extends LayoutEditPolicy {

	private IConfigurationProvider _configurationProvider;

	/**
	 * Creates a new ShapeForbidLayoutEditPolicy.
	 * 
	 * @param configurationProvider
	 *            The IConfigurationProviderInternal.
	 */
	protected ShapeForbidLayoutEditPolicy(IConfigurationProvider configurationProvider) {
		_configurationProvider = configurationProvider;
	}

	protected final IConfigurationProvider getConfigurationProvider() {
		return _configurationProvider;
	}

	/**
	 * Returns null.
	 * 
	 * @see org.eclipse.gef.editpolicies.LayoutEditPolicy#createChildEditPolicy(org.eclipse.gef.EditPart)
	 */
	@Override
	protected EditPolicy createChildEditPolicy(EditPart child) {
		return null;
	}

	/**
	 * Returns null.
	 * 
	 * @see org.eclipse.gef.editpolicies.LayoutEditPolicy#getCreateCommand(org.eclipse.gef.requests.CreateRequest)
	 */
	@Override
	protected Command getCreateCommand(CreateRequest request) {
		return null;
	}

	/**
	 * Returns null.
	 * 
	 * @see org.eclipse.gef.editpolicies.LayoutEditPolicy#getMoveChildrenCommand(org.eclipse.gef.Request)
	 */
	@Override
	protected Command getMoveChildrenCommand(Request request) {
		return null;
	}

	/**
	 * Returns null.
	 * 
	 * @see org.eclipse.gef.editpolicies.LayoutEditPolicy#getDeleteDependantCommand(org.eclipse.gef.Request)
	 */
	@Override
	protected Command getDeleteDependantCommand(Request request) {
		return null;
	}
}