/*
 * Copyright (c) 2006 Stiftung Deutsches Elektronen-Synchroton,
 * Member of the Helmholtz Association, (DESY), HAMBURG, GERMANY.
 *
 * THIS SOFTWARE IS PROVIDED UNDER THIS LICENSE ON AN "../AS IS" BASIS.
 * WITHOUT WARRANTY OF ANY KIND, EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED
 * TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR PARTICULAR PURPOSE AND
 * NON-INFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
 * FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE. SHOULD THE SOFTWARE PROVE DEFECTIVE
 * IN ANY RESPECT, THE USER ASSUMES THE COST OF ANY NECESSARY SERVICING, REPAIR OR
 * CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE.
 * NO USE OF ANY SOFTWARE IS AUTHORIZED HEREUNDER EXCEPT UNDER THIS DISCLAIMER.
 * DESY HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
 * OR MODIFICATIONS.
 * THE FULL LICENSE SPECIFYING FOR THE SOFTWARE THE REDISTRIBUTION, MODIFICATION,
 * USAGE AND OTHER RIGHTS AND OBLIGATIONS IS INCLUDED WITH THE DISTRIBUTION OF THIS
 * PROJECT IN THE FILE LICENSE.HTML. IF THE LICENSE IS NOT INCLUDED YOU MAY FIND A COPY
 * AT HTTP://WWW.DESY.DE/LEGAL/LICENSE.HTM
 */
package org.csstudio.sds.internal.rules;

import org.csstudio.sds.model.IRule;
import org.eclipse.core.runtime.Platform;

/**
 * Simple fast color rule.
 *
 * @author Alexander Will
 * @version $Revision: 1.2 $
 *
 */
public final class SimpleColorRule implements IRule {

	/**
	 * RED color.
	 */
	static final String COLOR_RED = "#ff0000";

	/**
	 * YELLOW color.
	 */
	static final String COLOR_YELLOW = "#FFFF00";

	/**
	 * GREEN color.
	 */
	static final String COLOR_GREEN = "#00ff00";

	/**
	 * BLACK color.
	 */
	static final String COLOR_BLACK = "#000000";

	/**
	 * Standard constructor.
	 */
	public SimpleColorRule() {
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public Object evaluate(final Object[] arguments) {
		if ((arguments != null) && (arguments.length > 0)) {
			if (arguments[0] instanceof Number) {
				double d = ((Number) arguments[0]).doubleValue();

				if (d > 66) {
					return COLOR_RED;
				}

				if (d > 33) {
					return COLOR_YELLOW;
				}

				if (d > 0) {
					return COLOR_GREEN;
				}
			}
		}

		return COLOR_BLACK;
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	public String getDescription() {
	    String ls = System.getProperty(Platform.PREF_LINE_SEPARATOR);
	    return "When the value is a Number and "+ls
	    	 + "value > 66 return red: "+COLOR_RED+ls
	         + "value > 33 return yellow: "+COLOR_YELLOW+ls
	         + "value >  0 return green: "+COLOR_GREEN+ls
	         + "else return black: "+COLOR_BLACK;
	}
}