/* An abstract menu factory that creates context menus using item factories

 Copyright (c) 2000-2006 The Regents of the University of California.
 All rights reserved.
 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the above
 copyright notice and the following two paragraphs appear in all copies
 of this software.

 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
 FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 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 OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.

 PT_COPYRIGHT_VERSION_2
 COPYRIGHTENDKEY

 */
package ptolemy.vergil.toolbox;

import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import ptolemy.kernel.util.NamedObj;
import diva.canvas.Figure;
import diva.graph.GraphController;
import diva.gui.toolbox.JContextMenu;
import diva.gui.toolbox.MenuFactory;

//////////////////////////////////////////////////////////////////////////
//// PtolemyMenuFactory

/**
 A menu factory that contains a list of item factories.
 When asked to create a context menu, This class first
 takes the figure and finds the ptolemy object associated with it.  Then it
 passes the ptolemy object to each menu item factory that it contains to add
 the menu items.  Lastly, it returns the resulting menu.  This seems simple,
 except for the fact that for different types of figures, and different
 visual notations, the mapping between figure and the interesting ptolemy
 object is different.  Hence, Node and Edge Controllers will often need
 subclasses of this factory to get the correct ptolemy object.

 @author Steve Neuendorffer
 @version $Id$
 @since Ptolemy II 1.0
 @Pt.ProposedRating Red (eal)
 @Pt.AcceptedRating Red (johnr)
 */
public class PtolemyMenuFactory implements MenuFactory {

    /** Create a new menu factory that contains no menu item factories.
     *  @param controller The controller.
     */
    public PtolemyMenuFactory(GraphController controller) {
        _factoryList = new LinkedList();
        _controller = controller;
    }

    ///////////////////////////////////////////////////////////////////
    ////                         public methods                    ////

    /** Add a menu item factory to this creator.
     *  @param factory The menu item factory to add.
     */
    public void addMenuItemFactory(MenuItemFactory factory) {
        _factoryList.add(factory);
    }

    /** Create an instance of the menu associated with this factory.
     *  @param figure The figure for which to create a context menu.
     *  @return The instance of the menu.
     */
    public JContextMenu create(Figure figure) {
        NamedObj object = _getObjectFromFigure(figure);

        if (object == null) {
            return null;
        }

        JContextMenu menu = new JContextMenu(object, object.getFullName());
        Iterator i = menuItemFactoryList().iterator();

        while (i.hasNext()) {
            MenuItemFactory factory = (MenuItemFactory) i.next();
            factory.create(menu, object);
        }

        return menu;
    }

    /** Return the graph controller that created this menu factory.
     *  @return The controller.
     */
    public GraphController getController() {
        return _controller;
    }

    /** Return the list of menu item factories.
     * @return An unmodifiable list.
     */
    public List menuItemFactoryList() {
        return Collections.unmodifiableList(_factoryList);
    }

    /** Remove the given menu item factory from the factory list.
     *  @param factory The factory to be removed.
     */
    public void removeMenuItemFactory(MenuItemFactory factory) {
        _factoryList.remove(factory);
    }

    ///////////////////////////////////////////////////////////////////
    ////                         protected methods                 ////

    /** Return the Ptolemy object that the given figure represents.
     *  In this base class, we assume that the figure is attached to a
     *  a diva.graph.model object, and that object is attached to the
     *  correct ptolemy object.  In many cases, this is not the case,
     *  and you will have to override this function.
     *  @param figure The figure.
     *  @return The Ptolemy object that the given figure represents.
     */
    protected NamedObj _getObjectFromFigure(Figure figure) {
        Object object = figure.getUserObject();
        return (NamedObj) _controller.getGraphModel().getSemanticObject(object);
    }

    ///////////////////////////////////////////////////////////////////
    ////                     private members                       ////

    /** The graph controller.
     */
    private GraphController _controller;

    /** The menu item factories.
     */
    private List _factoryList;
}