/*
 * Copyright (c) 2008-2009, Piccolo2D project, http://piccolo2d.org
 * Copyright (c) 1998-2008, University of Maryland
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided
 * that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this list of conditions
 * and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions
 * and the following disclaimer in the documentation and/or other materials provided with the
 * distribution.
 *
 * None of the name of the University of Maryland, the name of the Piccolo2D project, or the names of its
 * contributors may be used to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package edu.umd.cs.piccolox.swt;

import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.Rectangle;

import edu.umd.cs.piccolo.PNode;
import edu.umd.cs.piccolo.nodes.PImage;
import edu.umd.cs.piccolo.util.PBounds;
import edu.umd.cs.piccolo.util.PPaintContext;

/**
 * <b>PSWTImage</b> is a wrapper around a org.eclipse.swt.graphics.Image.
 * 
 * @version 1.0
 * @author Jesse Grosjean
 */
public class PSWTImage extends PNode {
	private static final long serialVersionUID = 1L;

	private transient final PSWTCanvas canvas;

	private transient Image image;

	/**
	 * Constructs a PSWTImage attached to the provided canvas and with a null
	 * image.
	 * 
	 * The developer will need to call setImage for this node to be useful.
	 * 
	 * TODO: determine if canvas is actually necessary
	 * 
	 * @param canvas
	 *            canvas to associate with the image node
	 */
	public PSWTImage(final PSWTCanvas canvas) {
		this.canvas = canvas;
		canvas.addDisposeListener(new DisposeListener() {
			public void widgetDisposed(final DisposeEvent de) {
				disposeImage();
			}
		});
	}

	/**
	 * Constructs a PSWTImage wrapping the provided image.
	 * 
	 * @param canvas
	 *            canvas to associate with the image node
	 * @param image
	 *            image to be wrapped by this PSWTImage
	 */
	public PSWTImage(final PSWTCanvas canvas, final Image image) {
		this(canvas);
		setImage(image);
	}

	/**
	 * Constructs a PSWTImage wrapping the provided image after loading it from
	 * the file.
	 * 
	 * @param canvas
	 *            canvas to associate with the image node
	 * @param fileName
	 *            path to the image, will be loaded and converted to an Image
	 *            internally
	 */
	public PSWTImage(final PSWTCanvas canvas, final String fileName) {
		this(canvas);
		setImage(fileName);
	}

	/**
	 * Returns the image that is shown by this node, may be null.
	 * 
	 * @return the image that is shown by this node
	 */
	public Image getImage() {
		return image;
	}

	/**
	 * Set the image that is wrapped by this PImage node. This method will also
	 * load the image using a MediaTracker before returning. And if the this
	 * PImage is accelerated that image will be copied into an accelerated image
	 * if needed. Note that this may cause undesired results with images that
	 * have transparent regions, for those cases you may want to set the PImage
	 * to be not accelerated.
	 */
	public void setImage(final String fileName) {
		setImage(new Image(canvas.getDisplay(), fileName));
	}

	/**
	 * Set the image that is wrapped by this PImage node. This method will also
	 * load the image using a MediaTracker before returning. And if the this
	 * PImage is accelerated that I'm will be copied into an accelerated image
	 * if needed. Note that this may cause undesired results with images that
	 * have transparent regions, for those cases you may want to set the PImage
	 * to be not accelerated.
	 */
	public void setImage(final Image newImage) {
		final Image old = image;
		image = newImage;

		if (image != null) {
			final Rectangle bounds = getImage().getBounds();
			setBounds(0, 0, bounds.width, bounds.height);
			invalidatePaint();
		}

		firePropertyChange(PImage.PROPERTY_CODE_IMAGE, PImage.PROPERTY_IMAGE,
				old, image);
	}

	/**
	 * Subclasses may override this method to provide different image dispose
	 * behavior.
	 */
	protected void disposeImage() {
		if (image != null) {
			image.dispose();
		}
	}

	/** {@inheritDoc} */
	protected void paint(final PPaintContext paintContext) {
		if (getImage() != null) {
			final Rectangle r = image.getBounds();
			final PBounds b = getBoundsReference();
			final SWTGraphics2D g2 = (SWTGraphics2D) paintContext.getGraphics();

			if (b.x == 0 && b.y == 0 && b.width == r.width
					&& b.height == r.height) {
				g2.drawImage(image, 0, 0);
			} else {
				g2.translate(b.x, b.y);
				g2.scale(b.width / r.width, b.height / r.height);
				g2.drawImage(image, 0, 0);
				g2.scale(r.width / b.width, r.height / b.height);
				g2.translate(-b.x, -b.y);
			}
		}
	}
}