/*******************************************************************************
 * Copyright (c) 2004 - 2006 University Of British Columbia and others.
 * 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:
 *     University Of British Columbia - initial API and implementation
 *******************************************************************************/
package org.eclipse.mylyn.internal.tasklist;

public class RelativePathUtil {
	public static String findRelativePath(String baseDirectory, String filePath) {
		if (filePath.startsWith(baseDirectory)) {
			return filePath.substring(baseDirectory.length(), filePath.lastIndexOf('.'));
		} else {
			StringBuffer result = new StringBuffer(filePath.length());
			String[] rootFolders = baseDirectory.split("/");
			String[] pathFolders = filePath.split("/");
			int diff = 0;
			for (int i = 0; i < pathFolders.length; i++) {
				if (!rootFolders[i].equals(pathFolders[i])) {
					diff = i;
					while (i < rootFolders.length) {
						result.append('.');
						result.append('.');
						result.append('/');
						i++;
					}
					while (diff < pathFolders.length - 1) {
						result.append(pathFolders[diff]);
						diff++;
					}
					result.append(pathFolders[diff].substring(0, pathFolders[diff].lastIndexOf('.')));
				}
			}
			return result.toString();
		}
	}
}