/*
 * This file is part of l2jserver <l2jserver.com>.
 *
 * l2jserver is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * l2jserver is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with l2jserver.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.l2jserver.util;

/**
 * This class contains utilities that are used when we are working with classes
 * 
 * @author <a href="http://www.rogiel.com">Rogiel</a>
 */
public class ClassUtils {
	/**
	 * Return true if class a is either equivalent to class b, or if class a is
	 * a subclass of class b, i.e. if a either "extends" or "implements" b. Note
	 * that either or both "Class" objects may represent interfaces.
	 * 
	 * @param a
	 *            class
	 * @param b
	 *            class
	 * @return true if a == b or a extends b or a implements b
	 */
	public static boolean isSubclass(Class<?> a, Class<?> b) {
		// We rely on the fact that for any given java class or
		// primitive type there is a unique Class object, so
		// we can use object equivalence in the comparisons.
		if (a == b) {
			return true;
		}
		if (a == null || b == null) {
			return false;
		}
		for (Class<?> x = a; x != null; x = x.getSuperclass()) {
			if (x == b) {
				return true;
			}
			if (b.isInterface()) {
				Class<?> interfaces[] = x.getInterfaces();
				for (Class<?> anInterface : interfaces) {
					if (isSubclass(anInterface, b)) {
						return true;
					}
				}
			}
		}
		return false;
	}

	/**
	 * Checks if class in member of the package
	 * 
	 * @param clazz
	 *            class to check
	 * @param packageName
	 *            package
	 * @return true if is member
	 */
	public static boolean isPackageMember(Class<?> clazz, String packageName) {
		return isPackageMember(clazz.getName(), packageName);
	}

	/**
	 * Checks if classNames belongs to package
	 * 
	 * @param className
	 *            class name
	 * @param packageName
	 *            package
	 * @return true if belongs
	 */
	public static boolean isPackageMember(String className, String packageName) {
		if (!className.contains(".")) {
			return packageName == null || packageName.isEmpty();
		} else {
			String classPackage = className.substring(0,
					className.lastIndexOf('.'));
			return packageName.equals(classPackage);
		}
	}
}
