/* $Id: SelectionRerouteEdge.java 17865 2010-01-12 20:45:26Z linus $

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

  * Copyright (c) 2009 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:

  *    bobtarling

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

  *

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

  */

 // Copyright (c) 1996-2007 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

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

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 // UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 package org.argouml.uml.diagram.ui;

 import org.argouml.uml.diagram.UMLMutableGraphSupport;

 import java.awt.Rectangle;

 import java.awt.event.MouseEvent;

 import java.util.Enumeration;

 import org.tigris.gef.base.Globals;

 import org.tigris.gef.base.Editor;

 import org.tigris.gef.base.Layer;

 import org.tigris.gef.base.LayerManager;

 import org.tigris.gef.base.ModeManager;

 import org.tigris.gef.base.ModeCreatePolyEdge;

 import org.tigris.gef.base.FigModifyingMode;

 import org.tigris.gef.presentation.Fig;

 import org.tigris.gef.presentation.FigEdge;

 /**

  * A general class for rerouting edges, achieved by delegating

  * the re-routing logic to the graphmodels; extends

  * functionality in SelectionEdgeClarifiers.

  *

  * <p>If a graphmodel does not override canChangeConnectedNode()

  * then rerouting is not possible and ArgoUML should behave as if

  * rerouting had never been implemented.

  *

  * @author  alexb

  * @since 0.13.2

  */

 public class SelectionRerouteEdge extends SelectionEdgeClarifiers {

     /**

      * Used to determine if the association is now to self,

      * in which case The association needs automatic layout.

      */

     private FigNodeModelElement sourceFig;

     /**

      * Used to determine if the association is now to self,

      * in which case The association needs automatic layout.

      */

     private FigNodeModelElement destFig;

     /**

      * The re-routing capability it armed if the mouse was previously

      * dragged.

      * <p>prevents just selecting the message then clicking somewhere

      * else on the diagram,

      */

     private boolean armed;

     /**

      * The index of the point on the line of the message.

      * <p>0 = sender end

      * <p>1..* = receiver end

      */

     private int pointIndex;

     /** 

      * Creates a new instance of SelectionRerouteEdge

      *

      * @param feme the given Fig

      */

     public SelectionRerouteEdge(FigEdgeModelElement feme) {

         // TODO: There is a cyclic dependency between SelectionRerouteEdge

         // and FigEdgeModelElement

         super(feme);

         // set it to an invalid number by default

         // to make sure it is set correctly.

         pointIndex = -1;

     }

     /**

      * Set up for re-routing.

      *

      * {@inheritDoc}

      */

     public void mousePressed(MouseEvent me) {

         // calculate the source and dest figs for to self assoc

         sourceFig =

             (FigNodeModelElement) ((FigEdge) getContent()).getSourceFigNode();

         destFig = 

             (FigNodeModelElement) ((FigEdge) getContent()).getDestFigNode();

         final Rectangle mousePosition =

             new Rectangle(me.getX() - 5, me.getY() - 5, 10, 10);

         //reset the pointIndex

         pointIndex = -1;

         final int npoints = getContent().getNumPoints();

         final int[] xs = getContent().getXs();

         final int[] ys = getContent().getYs();

         if (mousePosition.contains(xs[0], ys[0])) {

             pointIndex = 0;

         } else if (mousePosition.contains(

                 xs[npoints - 1], ys[npoints - 1])) {

             pointIndex = npoints - 1;

         }

         super.mousePressed(me);

     }

     /*

      * Need to 'arm' the rerouting capability with mouseDragged().

      * <p>

      * Don't arm if the edtior's current mode is a figedge create mode,

      * because once a new edge has been created it is not deselected,

      * therefore on the next create an unwanted reroute is performed.

      *

      * @see java.awt.event.MouseMotionListener#mouseDragged(java.awt.event.MouseEvent)

      */

     public void mouseDragged(MouseEvent me) {

         Editor editor = Globals.curEditor();

         ModeManager modeMgr = editor.getModeManager();

         FigModifyingMode fMode = modeMgr.top();

         if (!(fMode instanceof ModeCreatePolyEdge)) {

             armed = true;

         }

         super.mouseDragged(me);

     }

     /*

      * Perform re-routing if src/dest nodes have changed.

      *

      * <p>This method needs to be 'armed' by a previous mouseDragged()

      * to avoid the situation where the user just clicks on the node

      * then clicks on some unrelated Fig, without moving the edge...

      *

      * <p>TODO: improve the fig finding algorithm to find the top most fig

      * in the layer. will be useful for nested states in a statechart.

      *

      * @see java.awt.event.MouseListener#mouseReleased(java.awt.event.MouseEvent)

      */

     public void mouseReleased(MouseEvent me) {

         // check pre-conds

         if (me.isConsumed() || !armed || pointIndex == -1) {

             armed = false;

             super.mouseReleased(me);

             return;

         }

         //Set-up:

         int x = me.getX(), y = me.getY();

         // the fig that was under the mouse when it was released

         FigNodeModelElement newFig = null;

         //make a nice little target area:

         Rectangle mousePoint = new Rectangle(x - 5, y - 5, 5, 5);

         // and find the Fig:

         Editor editor = Globals.curEditor();

         LayerManager lm = editor.getLayerManager();

         Layer active = lm.getActiveLayer();

         Enumeration figs = active.elementsIn(mousePoint);

         // last is the top fig.

         while (figs.hasMoreElements()) {

             Fig candidateFig = (Fig) figs.nextElement();

             if (candidateFig instanceof FigNodeModelElement

                     && candidateFig.isSelectable()) {

                 newFig = (FigNodeModelElement) candidateFig;

             }

         }

         // check intermediate post-condition.

         if (newFig == null) {

             armed = false;

             super.mouseReleased(me);

             return;

         }

         UMLMutableGraphSupport mgm =

             (UMLMutableGraphSupport) editor.getGraphModel();

         FigNodeModelElement oldFig = null;

         boolean isSource = false;

         if (pointIndex == 0) {

             oldFig = sourceFig;

             isSource = true;

         }

         else {

             oldFig = destFig;

         }

         // delegate the re-routing to graphmodels.

         if (mgm.canChangeConnectedNode(newFig.getOwner(),

                                        oldFig.getOwner(),

                                        this.getContent().getOwner())) {

             mgm.changeConnectedNode(newFig.getOwner(),

                                     oldFig.getOwner(),

                                     this.getContent().getOwner(),

                                     isSource);

         }

         editor.getSelectionManager().deselect(getContent());

         armed = false;

         // TODO: There is a cyclic dependency between SelectionRerouteEdge

         // and FigEdgeModelElement

         FigEdgeModelElement figEdge = (FigEdgeModelElement) getContent();

         figEdge.determineFigNodes();

         figEdge.computeRoute();

         super.mouseReleased(me);

         return;

     }

 }