/*
 Copyright (c) 1998-2005 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  BASIS, AND THE UNIVERSITY OF
 CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.

 PT_COPYRIGHT_VERSION_2
 COPYRIGHTENDKEY
 *
 */
package diva.canvas.interactor;

import java.util.Hashtable;

import diva.canvas.Figure;
import diva.canvas.FigureContainer;
import diva.canvas.FigureDecorator;
import diva.canvas.toolbox.BasicHighlighter;

/** A basic implementation of a selection renderer. This
 * implementation wraps each selected figure in an instance of
 * a FigureDecorator. The figure decorator is obtained by
 * cloning a prototype decorator, accessible through the
 * get/setFigureDecorator() methods. The default prototype
 * is an instance of BasicHighlighter. Often, the prototype
 * decorator will be set to instances of one of the Manipulator
 * classes.
 *
 * @version        $Id$
 * @author         John Reekie
 */
public class BasicSelectionRenderer implements SelectionRenderer {
    /** Mapping from figures to decorators
     */
    private Hashtable _decorators = new Hashtable();

    /** The prototype decorator
     */
    private FigureDecorator _prototypeDecorator;

    /** Create a new selection renderer with the default prototype
     * decorator.
     */
    public BasicSelectionRenderer() {
        _prototypeDecorator = new BasicHighlighter();
    }

    /** Create a new renderer with the given prototype decorator.
     */
    public BasicSelectionRenderer(FigureDecorator d) {
        _prototypeDecorator = d;
    }

    /** Get the prototype decorator.
     */
    public FigureDecorator getDecorator() {
        return _prototypeDecorator;
    }

    /** Test if the given figure is currently rendered selected.
     */
    public boolean isRenderedSelected(Figure figure) {
        return _decorators.containsKey(figure);
    }

    /** Set the rendering of the figure as deselected. The figure has
     * the decorator unwrapped off it and is inserted back into
     * its parent figure container, if there is one. If the figure is
     * not rendered selected, do nothing.
     */
    public void renderDeselected(Figure figure) {
        if (!_decorators.containsKey(figure)) {
            return;
        }

        // Rather than just get the parent of the figure, we must get
        // the decorator out of the hashtable, since other wrappers
        // may have been inserted between the figure and its
        // decorator
        FigureDecorator d = (FigureDecorator) _decorators.get(figure);

        if (d.getParent() != null) {
            figure.repaint();
            ((FigureContainer) d.getParent()).undecorate(d);
        }

        _decorators.remove(figure);
    }

    /** Set the rendering of the figure as selected. If the figure is
     * already rendered selected, just repaint. Otherwise create a new
     * BasicHighlighter, and wrap the figure in the decorator,
     * inserting the decorator into the figure's parent.
     */
    public void renderSelected(Figure figure) {
        if (_decorators.containsKey(figure)) {
            ((Figure) _decorators.get(figure)).repaint();
        } else {
            FigureContainer parent = (FigureContainer) figure.getParent();

            if (parent != null) {
                FigureDecorator d = _prototypeDecorator.newInstance(figure);
                parent.decorate(figure, d);
                _decorators.put(figure, d);
            }
        }
    }

    /** Set the prototype decorator.
     */
    public void setDecorator(FigureDecorator d) {
        _prototypeDecorator = d;
    }
}