/*
 * Created on 15/Mar/2003
 *
 */
package net.sourceforge.fenixedu.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

/**
 * @author Nuno Nunes
 * 
 */
public class EncryptionTools extends FenixUtil {

    /**
     * This Method encrypts a String
     * 
     * @param password
     * @return Encrypted Password
     */
    public static String encrypt(String password) {
	byte[] buf = new byte[password.length()];
	buf = password.getBytes();

	MessageDigest algorithm = null;
	try {
	    algorithm = MessageDigest.getInstance("SHA-1");
	} catch (NoSuchAlgorithmException e) {
	    throw new RuntimeException(e);
	}
	algorithm.reset();
	algorithm.update(buf);
	byte[] digest1 = algorithm.digest();
	return new String(digest1);
    }

    /**
     * This Method compares two encrypted passwords and returns the result of
     * the comparison
     * 
     * @param encryptedPassword
     * @param password2
     * @return boolean
     */
    public static boolean compareEncryptedPasswords(String encryptedPassword1, String encryptedPassword2) {
	byte[] buf = new byte[encryptedPassword1.length()];
	buf = encryptedPassword1.getBytes();

	MessageDigest algorithm = null;
	try {
	    algorithm = MessageDigest.getInstance("SHA-1");
	} catch (NoSuchAlgorithmException e) {
	    throw new RuntimeException(e);
	}
	algorithm.reset();
	algorithm.update(buf);

	byte[] digest1 = algorithm.digest();

	algorithm.reset();

	buf = new byte[encryptedPassword2.length()];
	buf = encryptedPassword2.getBytes();
	algorithm.update(buf);
	byte[] digest2 = algorithm.digest();

	if (digest1.length != digest2.length)
	    return false;

	for (int i = 0; i < digest1.length; i++) {
	    if (digest1[i] != digest2[i])
		return false;
	}
	return true;
    }

    /**
     * Compares a encrypted password with a non encrypted one
     * 
     * @param encryptedPassword
     * @param nonEncryptedPassword
     * @return
     */
    public static boolean compareEncryptedPasswordAndNonEncrypted(String encryptedPassword, String nonEncryptedPassword) {
	if (encryptedPassword.equals(encrypt(nonEncryptedPassword)))
	    return true;
	return false;

    }

}