EMFCompareStructureMergeViewerLabelProvider.java

/*******************************************************************************
 * Copyright (c) 2012, 2014 Obeo.
 * 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:
 *     Obeo - initial API and implementation
 *******************************************************************************/
package org.eclipse.emf.compare.ide.ui.internal.structuremergeviewer;

import org.eclipse.compare.structuremergeviewer.ICompareInput;
import org.eclipse.emf.common.notify.Adapter;
import org.eclipse.emf.common.notify.AdapterFactory;
import org.eclipse.emf.compare.ide.ui.internal.util.StyledStringConverter;
import org.eclipse.emf.compare.provider.EMFCompareEditPlugin;
import org.eclipse.emf.compare.provider.IItemStyledLabelProvider;
import org.eclipse.emf.compare.provider.spec.OverlayImageProvider;
import org.eclipse.emf.compare.rcp.ui.EMFCompareRCPUIPlugin;
import org.eclipse.emf.edit.provider.ItemProviderAdapter;
import org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider;
import org.eclipse.jface.viewers.DelegatingStyledCellLabelProvider.IStyledLabelProvider;
import org.eclipse.jface.viewers.StyledString;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Image;
import org.eclipse.ui.progress.PendingUpdateAdapter;

/**
 * A specialized {@link AdapterFactoryLabelProvider.FontAndColorProvider} for the structure merge viewer.
 * 
 * @author <a href="mailto:mikael.barbero@obeo.fr">Mikael Barbero</a>
 */
class EMFCompareStructureMergeViewerLabelProvider extends AdapterFactoryLabelProvider.FontAndColorProvider implements IStyledLabelProvider {

	protected StyledStringConverter styledStringConverter;

	private OverlayImageProvider overlayImageProvider;

	/**
	 * Constructor calling super {@link #FontAndColorProvider(AdapterFactory, Viewer)}.
	 * 
	 * @param adapterFactory
	 *            The adapter factory.
	 * @param viewer
	 *            The viewer.
	 */
	public EMFCompareStructureMergeViewerLabelProvider(AdapterFactory adapterFactory, Viewer viewer) {
		super(adapterFactory, viewer);
		overlayImageProvider = new OverlayImageProvider(EMFCompareEditPlugin.getPlugin());
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider#getText(java.lang.Object)
	 */
	@Override
	public String getText(Object element) {
		return getStyledText(element).getString();
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider#getFont(java.lang.Object)
	 */
	@Override
	public Font getFont(Object object) {
		if (object instanceof Adapter) {
			return super.getFont(((Adapter)object).getTarget());
		}
		return super.getFont(object);
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider#getForeground(java.lang.Object)
	 */
	@Override
	public Color getForeground(Object object) {
		if (object instanceof Adapter) {
			return super.getForeground(((Adapter)object).getTarget());
		}
		return super.getForeground(object);
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider#getBackground(java.lang.Object)
	 */
	@Override
	public Color getBackground(Object object) {
		if (object instanceof Adapter) {
			return super.getBackground(((Adapter)object).getTarget());
		}
		return super.getBackground(object);
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.emf.edit.ui.provider.AdapterFactoryLabelProvider#getImage(java.lang.Object)
	 */
	@Override
	public Image getImage(Object element) {
		final Image ret;
		if (element instanceof ItemProviderAdapter) {
			ret = super.getImage(element);
		} else if (element instanceof Adapter) {
			ret = super.getImage(((Adapter)element).getTarget());
		} else if (element instanceof ICompareInput) {
			ret = ((ICompareInput)element).getImage();
		} else if (element instanceof PendingUpdateAdapter) {
			ret = super.getImageFromObject(overlayImageProvider.getComposedImage(element,
					EMFCompareRCPUIPlugin.getImage("icons/full/toolb16/group.gif"))); //$NON-NLS-1$
		} else {
			ret = super.getImage(element);
		}

		return ret;
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see org.eclipse.jface.viewers.DelegatingStyledCellLabelProvider.IStyledLabelProvider.getStyledText(
	 *      java .lang.Object)
	 */
	@Override
	public StyledString getStyledText(Object element) {
		final StyledString ret;
		if (element instanceof ItemProviderAdapter) {
			ret = getStyledTextFromObject(element);
		} else if (element instanceof Adapter) {
			ret = getStyledTextFromObject(((Adapter)element).getTarget());
		} else if (element instanceof ICompareInput) {
			ret = getStyledTextFromObject(((ICompareInput)element).getName());
		} else if (element instanceof PendingUpdateAdapter) {
			ret = new StyledString("Please wait while computing the element to display...");
		} else {
			ret = getStyledTextFromObject(element);
		}
		return ret;
	}

	/**
	 * Returns the styled text string of the given <code>object</code> by adapting it to
	 * {@link IItemStyledLabelProvider} and asking for its
	 * {@link IItemStyledLabelProvider#getStyledText(Object) text}. Returns null if <code>object</code> is
	 * null.
	 * 
	 * @param object
	 *            the object from which we want a text
	 * @return the text, or null if object is null.
	 * @throws NullPointerException
	 *             if <code>adapterFactory</code> is null.
	 */
	private StyledString getStyledTextFromObject(final Object object) {
		if (object == null) {
			return null;
		}
		StyledString ret = null;
		Object itemStyledLabelProvider = getAdapterFactory().adapt(object, IItemStyledLabelProvider.class);
		if (itemStyledLabelProvider instanceof IItemStyledLabelProvider) {
			ret = getStyledStringConverter().toJFaceStyledString(
					((IItemStyledLabelProvider)itemStyledLabelProvider).getStyledText(object));
		}

		if (ret == null) {
			ret = new StyledString(object.toString());
		}

		return ret;
	}

	/**
	 * Returns the StyledStringConverter used to convert emf compare styled strings to jface styled strings.
	 * 
	 * @return the styledStringConverter.
	 */
	protected StyledStringConverter getStyledStringConverter() {
		if (styledStringConverter == null) {
			styledStringConverter = new StyledStringConverter(getDefaultFont(), getDefaultForeground(),
					getDefaultBackground());
		}
		return styledStringConverter;
	}
}