org.eclipse.osbp.xtext.reportdsl/src/org/eclipse/osbp/xtext/reportdsl/common/ColorUtilities.java

/**
 *                                                                            
 * Copyright (c) 2011, 2016 - Loetz GmbH&Co.KG (69115 Heidelberg, Germany)
 *                                                                            
 * 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:   
 * Christophe Loetz (Loetz GmbH&Co.KG) - initial implementation 
 */
package org.eclipse.osbp.xtext.reportdsl.common;

import org.eclipse.osbp.xtext.reportdsl.Color;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 *  Utilities to convert different Color types.
 */
public class ColorUtilities {

	private final static Logger log = LoggerFactory.getLogger(ColorUtilities.class);
	
	/**
	 * @param   source  a color attribute of the Report DSL Grammar
	 * @return  a AWT color is the source is parseable or <code>java.awt.Color.BLACK</code> otherwise
	 */
	public static java.awt.Color convertToAwtColor(Color source) {
		return convertToAwtColor(source.getColor());
	}
	
	/**
	 * @param   source  a color string value
	 * @return  a AWT color is the source is parseable or <code>java.awt.Color.BLACK</code> otherwise
	 */
	public static java.awt.Color convertToAwtColor(String source) {
		java.awt.Color result = java.awt.Color.BLACK;
		if	(source != null) {
			if	(source.charAt(0) == '#') {
				int r = 0;
				int g = 0;
				int b = 0;
				switch (source.length()) {
					case 3:
						r = parseHex(source.substring(1, 3));
						g = r;
						b = r;
						break;
					case 4:
						r = parseHex(""+source.charAt(1)+source.charAt(1));
						g = parseHex(""+source.charAt(2)+source.charAt(2));
						b = parseHex(""+source.charAt(3)+source.charAt(3));
						break;
					case 7:
						r = parseHex(source.substring(1, 3));
						g = parseHex(source.substring(3, 5));
						b = parseHex(source.substring(5, 7));
						break;
					default:
						log.error("convertToAwtColor(): hex '"+source+"' is not parseable due to wrong value length!");
						break;
				}
				result = new java.awt.Color(r, g, b);
			}
			else {
				log.error("convertToAwtColor(): string '"+source+"' is not parseable due to wrong value format! Please use #rrggbb format!");
			}
		}
		else {
			log.error("convertToAwtColor(): string '<null>' is not parseable!");
		}
		return result;
	}
	
	private static int parseHex(String hex) {
		try {
			return Integer.decode("0x"+hex);
		}
		catch (NumberFormatException nfe) {
			log.error("convertToAwtColor(): hex '"+hex+"' is not parseable!");
			return 0;
		}
	}
}