bundles/org.eclipse.emf.rap.edit.ui.minimal/src/org/eclipse/emf/edit/ui/provider/ExtendedColorRegistry.java

/**
 * Copyright (c) 2008-2010 IBM Corporation and others.
 * 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 * IBM - Initial API and implementation
 */
// REUSED CLASS
package org.eclipse.emf.edit.ui.provider;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;

import org.eclipse.emf.common.util.URI;
import org.eclipse.emf.edit.provider.IItemColorProvider;
import org.eclipse.jface.resource.ColorDescriptor;
import org.eclipse.jface.resource.DeviceResourceException;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.widgets.Display;

/**
 * A color registry for converting a color description into an actual color.
 *
 * @see IItemColorProvider
 */
public class ExtendedColorRegistry
{
	public static final ExtendedColorRegistry INSTANCE = new ExtendedColorRegistry()
	{
		@Override
		public Color getColor(Color foregroundColor, Color backgroundColor, Object object)
		{
			return ExtendedImageRegistry.getInstance(ExtendedColorRegistry.class).getColor(foregroundColor,
				backgroundColor, object);
		}
	};

	protected Display display;
	protected HashMap<Collection<?>, Color> table = new HashMap<Collection<?>, Color>(10);

	public ExtendedColorRegistry()
	{
		display = Display.getCurrent();
		hookDisplayDispose(display);
	}

	public ExtendedColorRegistry(Display display)
	{
		this.display = display;
		hookDisplayDispose(display);
	}

	public Color getColor(Color foregroundColor, Color backgroundColor, Object object)
	{
		if (object instanceof Color)
		{
			return (Color) object;
		}
		else
		{
			final Collection<Object> key = new ArrayList<Object>(2);
			key.add(foregroundColor);
			key.add(backgroundColor);
			key.add(object);

			Color result = table.get(key);
			if (result == null)
			{
				if (object instanceof ColorDescriptor)
				{
					final ColorDescriptor colorDescriptor = (ColorDescriptor) object;
					try
					{
						result = colorDescriptor.createColor(display);
					} catch (final DeviceResourceException exception)
					{
						Activator.log(exception);
					}
				}
				else if (object instanceof URI)
				{
					final URI colorURI = (URI) object;
					if (!"color".equals(colorURI.scheme()))
					{
						throw new IllegalArgumentException("Only 'color' scheme is recognized" + colorURI);
					}

					RGB colorData;
					if ("rgb".equals(colorURI.authority()))
					{
						final int red = Integer.parseInt(colorURI.segment(0));
						final int green = Integer.parseInt(colorURI.segment(1));
						final int blue = Integer.parseInt(colorURI.segment(2));
						colorData = new RGB(red, green, blue);
					}
					else if ("hsb".equals(colorURI.authority()))
					{
						final float[] hsb = new float[3];
						for (int i = 0; i < 3; ++i)
						{
							final String segment = colorURI.segment(i);
							hsb[i] =
								"".equals(segment) || "foreground".equals(segment) ?
									foregroundColor.getRGB().getHSB()[i] :
									"background".equals(segment) ?
										backgroundColor.getRGB().getHSB()[i] :
										Float.parseFloat(segment);
						}
						colorData = new RGB(hsb[0], hsb[1], hsb[2]);
					}
					else
					{
						throw new IllegalArgumentException("Only 'rgb' and 'hsb' authority are recognized" + colorURI);
					}

					try
					{
						result = ColorDescriptor.createFrom(colorData).createColor(display);
					} catch (final DeviceResourceException exception)
					{
						Activator.log(exception);
					}
				}

				if (result != null)
				{
					table.put(key, result);
				}
			}
			return result;
		}
	}

	protected void handleDisplayDispose()
	{
		for (final Color color : table.values())
		{
			color.dispose();
		}
		table = null;
	}

	protected void hookDisplayDispose(Display display)
	{
		display.disposeExec
			(new Runnable()
			{
				@Override
				public void run()
				{
					handleDisplayDispose();
				}
			});
	}
}