/* $Id: DnDJGraph.java 18729 2010-09-10 16:10:34Z bobtarling $

  *****************************************************************************

  * Copyright (c) 2009-2010 Contributors - see below

  * 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:

  *    Michiel van der Wulp

  *    Bob Tarling

  *****************************************************************************

  *

  * Some portions of this file was previously release using the BSD License:

  */

 // Copyright (c) 2005-2009 The Regents of the University of California. All

 // Rights Reserved. Permission to use, copy, modify, and distribute this

 // software and its documentation without fee, and without a written

 // agreement is hereby granted, provided that the above copyright notice

 // and this paragraph appear in all copies.  This software program and

 // documentation are copyrighted by The Regents of the University of

 // California. The software program and documentation are supplied "AS

 // IS", without any accompanying services from The Regents. The Regents

 // does not warrant that the operation of the program will be

 // uninterrupted or error-free. The end-user understands that the program

 // was developed for research purposes and is advised not to rely

 // exclusively on the program for any reason.  IN NO EVENT SHALL THE

 // UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,

 // SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,

 // ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF

 // THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF

 // SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY

 // WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF

 // MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE

 // PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF

 // CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT,

 // UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 package org.argouml.uml.diagram.ui;

 import java.awt.datatransfer.Transferable;

 import java.awt.datatransfer.UnsupportedFlavorException;

 import java.awt.dnd.DnDConstants;

 import java.awt.dnd.DropTarget;

 import java.awt.dnd.DropTargetDragEvent;

 import java.awt.dnd.DropTargetDropEvent;

 import java.awt.dnd.DropTargetEvent;

 import java.awt.dnd.DropTargetListener;

 import java.io.IOException;

 import java.util.Collection;

 import java.util.Iterator;

 import org.apache.log4j.Logger;

 import org.argouml.kernel.Owned;

 import org.argouml.ui.TransferableModelElements;

 import org.argouml.uml.diagram.ArgoDiagram;

 import org.argouml.uml.diagram.DiagramElement;

 import org.argouml.uml.diagram.DiagramUtils;

 import org.tigris.gef.base.Diagram;

 import org.tigris.gef.base.Editor;

 import org.tigris.gef.base.Globals;

 import org.tigris.gef.graph.ConnectionConstrainer;

 import org.tigris.gef.graph.GraphModel;

 import org.tigris.gef.graph.MutableGraphModel;

 import org.tigris.gef.graph.presentation.JGraph;

 import org.tigris.gef.presentation.Fig;

 import org.tigris.gef.presentation.FigNode;

 /**

  * This is a JGraph with Drag and Drop capabilities.

  *

  * @author mvw

  */

 class DnDJGraph

     extends JGraph

     implements DropTargetListener {

     private static final Logger LOG = Logger.getLogger(DnDJGraph.class);

     /**

      * The constructor.

      *

      */

     public DnDJGraph() {

         super();

         makeDropTarget();

     }

     /**

      * The constructor.

      *

      * @param cc The ConnectionConstrainer.

      */

     public DnDJGraph(ConnectionConstrainer cc) {

         super(cc);

         makeDropTarget();

     }

     /**

      * The constructor.

      *

      * @param d The Diagram.

      */

     public DnDJGraph(Diagram d) {

         super(d);

         makeDropTarget();

     }

     /**

      * The constructor.

      *

      * @param gm The GraphModel.

      */

     public DnDJGraph(GraphModel gm) {

         super(gm);

         makeDropTarget();

     }

     /**

      * The constructor.

      *

      * @param ed The Editor.

      */

     public DnDJGraph(Editor ed) {

         super(ed);

         makeDropTarget();

     }

     private void makeDropTarget() {

         new DropTarget(this,

                 DnDConstants.ACTION_COPY_OR_MOVE,

                 this);

     }

     /*

      * @see java.awt.dnd.DropTargetListener#dragEnter(

      *         java.awt.dnd.DropTargetDragEvent)

      */

     public void dragEnter(DropTargetDragEvent dtde) {

             try {

                 if (dtde.isDataFlavorSupported(

                         TransferableModelElements.UML_COLLECTION_FLAVOR)) {

                     dtde.acceptDrag(dtde.getDropAction());

                     return;

                 }

             } catch (NullPointerException e) {

 //                        System.err.println("NullPointerException ignored.");

             }

             dtde.rejectDrag();

     }

     /*

      * @see java.awt.dnd.DropTargetListener#dragOver(

      *         java.awt.dnd.DropTargetDragEvent)

      */

     public void dragOver(DropTargetDragEvent dtde) {

             try {

                 ArgoDiagram dia = DiagramUtils.getActiveDiagram();

                 if (dia instanceof UMLDiagram 

                 /*&& ((UMLDiagram) dia).doesAccept(dtde.getSource())*/) {

                     dtde.acceptDrag(dtde.getDropAction());

                     return;

                 }

                 if (dtde.isDataFlavorSupported(

                         TransferableModelElements.UML_COLLECTION_FLAVOR)) {

                     dtde.acceptDrag(dtde.getDropAction());

                     return;

                 }

             } catch (NullPointerException e) {

 //                    System.err.println("NullPointerException ignored.");

             }

             dtde.rejectDrag();

     }

     /*

      * @see java.awt.dnd.DropTargetListener#dropActionChanged(

      *         java.awt.dnd.DropTargetDragEvent)

      */

     public void dropActionChanged(DropTargetDragEvent dtde) {

         // ignored

     }

     /*

      * @see java.awt.dnd.DropTargetListener#dragExit(

      *         java.awt.dnd.DropTargetEvent)

      */

     public void dragExit(DropTargetEvent dte) {

         // ignored

     }

     /*

      * @see java.awt.dnd.DropTargetListener#drop(

      *         java.awt.dnd.DropTargetDropEvent)

      */

     public void drop(DropTargetDropEvent dropTargetDropEvent) {

         Transferable tr = dropTargetDropEvent.getTransferable();

         //if the flavor is not supported, then reject the drop:

         if (!tr.isDataFlavorSupported(

                      TransferableModelElements.UML_COLLECTION_FLAVOR)) {

             dropTargetDropEvent.rejectDrop();

             return;

         }

         dropTargetDropEvent.acceptDrop(dropTargetDropEvent.getDropAction());

         //get the model elements that are being transfered.

         Collection modelElements; 

         try {

             ArgoDiagram diagram = DiagramUtils.getActiveDiagram();

             modelElements =

                 (Collection) tr.getTransferData(

                     TransferableModelElements.UML_COLLECTION_FLAVOR);

             Iterator i = modelElements.iterator();

             while (i.hasNext()) {

                 /* TODO: Why not call UMLDiagram.doesAccept() first, 

                  * like in ClassDiagramRenderer?  */

                 DiagramElement figNode = ((UMLDiagram ) diagram).drop(i.next(),

                         dropTargetDropEvent.getLocation());

                 if (figNode != null && figNode instanceof Owned) {

                     MutableGraphModel gm =

                         (MutableGraphModel) diagram.getGraphModel();

                     Object owner = ((Owned) figNode).getOwner();

                     if (!gm.getNodes().contains(owner)) {

                         gm.getNodes().add(owner);

                     }

                     Globals.curEditor().getLayerManager().getActiveLayer()

                             .add((Fig) figNode);

                     if (figNode instanceof FigNode && figNode instanceof Owned) {

                         gm.addNodeRelatedEdges(((Owned) figNode).getOwner());

                     }

                 }

             }

             dropTargetDropEvent.getDropTargetContext().dropComplete(true);

         } catch (UnsupportedFlavorException e) {

             LOG.debug("Exception caught", e);

         } catch (IOException e) {

             LOG.debug("Exception caught", e);

         }

     }

     /**

      * The UID.

      */

     private static final long serialVersionUID = -5753683239435014182L;

 }