org.eclipse.fmc.blockdiagram.editor/src/org/eclipse/fmc/blockdiagram/editor/features/ReconnectionFeature.java

/*******************************************************************************
 * <copyright>
 *
 * Copyright (c) 2013, 2013 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.fmc.blockdiagram.editor.features;

import org.eclipse.fmc.blockdiagram.editor.features.create.ConnectionCreateFeature;
import org.eclipse.fmc.blockdiagram.editor.model.ConnectionStyle;
import org.eclipse.fmc.blockdiagram.editor.util.FMCUtil;
import org.eclipse.graphiti.features.IFeatureProvider;
import org.eclipse.graphiti.features.context.IContext;
import org.eclipse.graphiti.features.context.IReconnectionContext;
import org.eclipse.graphiti.features.context.impl.CreateConnectionContext;
import org.eclipse.graphiti.features.context.impl.ReconnectionContext;
import org.eclipse.graphiti.features.impl.DefaultReconnectionFeature;
import org.eclipse.graphiti.mm.pictograms.Connection;
import org.eclipse.graphiti.mm.pictograms.Shape;
import org.eclipse.graphiti.services.Graphiti;

/**
 * This class extends DefaultReconnectionFeature and adds special behavior for
 * dots connections and support for connecting the shape behind something
 * non-connectable. Dots connections are special because it is possible to set the
 * target to an invisible shape. 
 * 
 * @author Benjamin Schmeling
 * 
 */
public class ReconnectionFeature extends DefaultReconnectionFeature {

	public ReconnectionFeature(IFeatureProvider fp) {
		super(fp);
	}
	
	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.graphiti.features.impl.DefaultReconnectionFeature#canReconnect
	 * (org.eclipse.graphiti.features.context.IReconnectionContext)
	 */
	@Override
	public boolean canReconnect(IReconnectionContext context) {
		Connection con = context.getConnection();
		Object model = FMCUtil.getIndependentObject(con);
		if (model == null) {
			model = FMCUtil.getBO(con);
		}

		ConnectionCreateFeature feature = null;

		feature = new ConnectionCreateFeature(getFeatureProvider(), "", "",
				model, ConnectionStyle.NORMAL, null);

		CreateConnectionContext ctx = new CreateConnectionContext();

		if (context.getTargetPictogramElement() instanceof Shape) {
			Shape s = ConnectionCreateFeature
					.getShapeBehindTextOrPicture((Shape) context
							.getTargetPictogramElement());
			if (s != null && !s.getAnchors().isEmpty()) {
				context.setTargetPictogramElement(s);
				((ReconnectionContext) context).setNewAnchor(s.getAnchors()
						.get(0));
			}
		}
		if (context.getOldAnchor() != null
				&& context.getOldAnchor().eContainer() instanceof Shape) {
			Shape shape = (Shape) context.getOldAnchor().eContainer();
			if (!shape.isVisible()) {
				// It is a Dots Connection
				return true;
			}
		}
		if (ReconnectionContext.RECONNECT_SOURCE.equals(context
				.getReconnectType())) {
			ctx.setSourceAnchor(context.getNewAnchor());
			ctx.setTargetAnchor(con.getEnd());
			if (con.getEnd() != null)
				ctx.setTargetPictogramElement(con.getEnd().getParent());
			if (context.getNewAnchor() != null)
				ctx.setSourcePictogramElement(context.getNewAnchor()
						.getParent());
		} else if (ReconnectionContext.RECONNECT_TARGET.equals(context
				.getReconnectType())) {
			ctx.setSourceAnchor(con.getStart());
			ctx.setTargetAnchor(context.getNewAnchor());
			ctx.setSourcePictogramElement(con.getStart().getParent());
			if (context.getNewAnchor() != null)
				ctx.setTargetPictogramElement(context.getNewAnchor()
						.getParent());
		}
		return feature.canCreate(ctx);
	
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.graphiti.features.impl.DefaultReconnectionFeature#execute
	 * (org.eclipse.graphiti.features.context.IContext)
	 */
	@Override
	public void execute(IContext context) {
		// Handle Dots connection with invisible anchor shape
		if (context instanceof IReconnectionContext) {
			IReconnectionContext reCtx = (IReconnectionContext) context;
			if (reCtx.getNewAnchor() == null) {
				Shape shape = (Shape) reCtx.getOldAnchor().eContainer();
				Graphiti.getGaService().setLocation(
						shape.getGraphicsAlgorithm(),
						reCtx.getTargetLocation().getX(),
						reCtx.getTargetLocation().getY());
			} else
				super.execute(context);
		} else
			super.execute(context);
	}
}