EDIT

// $Id$

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy 

* http://www.e-taxonomy.eu

* 

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.taxeditor.ui.forms;

import java.io.InputStream;

import java.net.URI;

import org.eclipse.core.runtime.IProgressMonitor;

import org.eclipse.core.runtime.IStatus;

import org.eclipse.core.runtime.Status;

import org.eclipse.core.runtime.jobs.Job;

import org.eclipse.jface.operation.IRunnableWithProgress;

import org.eclipse.swt.events.PaintEvent;

import org.eclipse.swt.events.PaintListener;

import org.eclipse.swt.graphics.GC;

import org.eclipse.swt.graphics.Image;

import org.eclipse.swt.graphics.Rectangle;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Display;

import org.eclipse.swt.widgets.Event;

import org.eclipse.ui.forms.widgets.TableWrapData;

import eu.etaxonomy.cdm.common.UriUtils;

import eu.etaxonomy.taxeditor.store.StoreUtil;

/**

 * <p>ImageElement class.</p>

 *

 * @author n.hoffmann

 * @created Sep 24, 2010

 * @version 1.0

 */

public class ImageElement extends AbstractCdmFormElement implements PaintListener{

	private URI imageUri;

	private Image image;

	private Rectangle imageMaxBounds;

	private Composite container;

	/**

	 * <p>Constructor for ImageElement.</p>

	 *

	 * @param formFactory a {@link eu.etaxonomy.taxeditor.ui.forms.CdmFormFactory} object.

	 * @param parentElement a {@link eu.etaxonomy.taxeditor.ui.forms.ICdmFormElement} object.

	 * @param imageUri a {@link java.net.URI} object.

	 * @param style a int.

	 */

	protected ImageElement(CdmFormFactory formFactory, ICdmFormElement parentElement, URI imageUri, int style) {

		super(formFactory, parentElement);

		setImageUri(imageUri);

		loadImage();

		container = new Composite(getLayoutComposite(), style);

		container.setLayoutData(CdmFormFactory.FILL(2, 1));

		container.addPaintListener(this);

	}

	/* (non-Javadoc)

	 * @see eu.etaxonomy.taxeditor.forms.ISelectable#setSelected(boolean)

	 */

	/** {@inheritDoc} */

	@Override

	public void setSelected(boolean selected) {

	}

	/**

	 * <p>Setter for the field <code>imageUri</code>.</p>

	 *

	 * @param uri a {@link java.net.URI} object.

	 */

	public void setImageUri(URI uri) {

		this.imageUri = uri;

	}

	/**

	 * <p>Getter for the field <code>imageUri</code>.</p>

	 *

	 * @return the imageUri

	 */

	public URI getImageUri() {

		return imageUri;

	}

	public void loadImage(){

		loadImage(null);

	}

	public void loadImage(final Runnable postRunnable){

		if(getImageUri() != null){

			Job job = new Job("Loading image") {

				@Override

				protected IStatus run(IProgressMonitor monitor) {

					IRunnableWithProgress runnable = getLoadImageRunnable(postRunnable);

					try {

						runnable.run(monitor);

					} catch (Exception e) {

						StoreUtil.errorDialog("Could not load image", getClass(), e.getMessage()  + ": " +  getImageUri(), e);

					}

					return Status.OK_STATUS;

				}

			};

			job.schedule();

		}

	}

	public IRunnableWithProgress getLoadImageRunnable(final Runnable postRunnable){

		final Display display = getLayoutComposite().getDisplay(); 

		IRunnableWithProgress runnable = new IRunnableWithProgress(){

			@Override

			public void run(IProgressMonitor monitor) {

				try {	

					monitor.beginTask("Loading: " + getImageUri(), IProgressMonitor.UNKNOWN);

					InputStream imageStream = UriUtils.getInputStream(imageUri);

					image = new Image(Display.getCurrent(), imageStream);

					// redraw the image container

					display.asyncExec(new Runnable(){

						@Override

						public void run() {

							if(! getLayoutComposite().isDisposed()){

								Event untypedEvent = new Event();

								untypedEvent.widget = container;

								PaintEvent event = new PaintEvent(untypedEvent);

								event.gc = new GC(container);

								paintControl(event);

								getLayoutComposite().layout();

							}

						}

					});

					// execute the external runnable

					if(postRunnable != null){

						display.asyncExec(postRunnable);

					}

					monitor.done();					

				}catch (Exception e) {

					StoreUtil.errorDialog("Could not load image", getClass(), e.getMessage()  + ": " + imageUri , e);

				} 

			}					

		};

		return runnable;

	}

	private void calculateImageBounds(){

		Rectangle imageBounds = image.getBounds();

		Rectangle containerBounds = container.getBounds();

		Integer imgWidth = imageBounds.width;

		Integer imgHeight = imageBounds.height;

		Float ratio = imgHeight.floatValue()/imgWidth.floatValue();

		Integer width = containerBounds.width;

		Float height = width * ratio;

		imageMaxBounds = new Rectangle(containerBounds.x, containerBounds.y, width, height.intValue());

	}

	/* (non-Javadoc)

	 * @see org.eclipse.swt.events.PaintListener#paintControl(org.eclipse.swt.events.PaintEvent)

	 */

	/** {@inheritDoc} */

	@Override

	public void paintControl(PaintEvent e) {

		if(image != null){

			calculateImageBounds();

			Composite composite = (Composite) e.widget;

			TableWrapData layoutData = CdmFormFactory.FILL(2, 1);

			layoutData.heightHint = imageMaxBounds.height;

			composite.setLayoutData(layoutData);

			e.gc.drawImage(image, 0, 0, image.getBounds().width, image.getBounds().height, 0, 0, imageMaxBounds.width, imageMaxBounds.height);

			e.gc.dispose();

		}		

	}

}