/*
 * MM JDBC Drivers for MySQL
 *
 * $Id: Util.java,v 1.4 2002/04/21 03:03:47 mark_matthews Exp $
 *
 * Copyright (C) 1998 Mark Matthews <mmatthew@worldserver.com>
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 * 
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA  02111-1307, USA.
 *
 * See the COPYING file located in the top-level-directory of
 * the archive of this library for complete text of license.
 */

package com.mysql.jdbc;

import java.io.ObjectInputStream;

public class Util {
	// Right from Monty's code

	static String newCrypt(String Passwd, String Seed) {
		byte b;
		double d;

		if (Passwd == null || Passwd.length() == 0)
			return Passwd;

		long[] pw = newHash(Seed);
		long[] msg = newHash(Passwd);

		long max = 0x3fffffffL;
		long seed1 = (pw[0] ^ msg[0]) % max;
		long seed2 = (pw[1] ^ msg[1]) % max;

		char[] chars = new char[Seed.length()];

		for (int i = 0; i < Seed.length(); i++) {
			seed1 = (seed1 * 3 + seed2) % max;
			seed2 = (seed1 + seed2 + 33) % max;
			d = (double) seed1 / (double) max;
			b = (byte) java.lang.Math.floor((d * 31) + 64);
			chars[i] = (char) b;
		}

		seed1 = (seed1 * 3 + seed2) % max;
		seed2 = (seed1 + seed2 + 33) % max;
		d = (double) seed1 / (double) max;
		b = (byte) java.lang.Math.floor(d * 31);

		for (int i = 0; i < Seed.length(); i++)
			chars[i] ^= (char) b;

		return new String(chars);
	}

	static String oldCrypt(String Passwd, String Seed) {
		long hp, hm, s1, s2;
		long max = 0x01FFFFFF;
		double d;
		byte b;

		if (Passwd == null || Passwd.length() == 0)
			return Passwd;

		hp = oldHash(Seed);
		hm = oldHash(Passwd);
		long nr = hp ^ hm;
		nr %= max;
		s1 = nr;
		s2 = nr / 2;

		char[] chars = new char[Seed.length()];

		for (int i = 0; i < Seed.length(); i++) {
			s1 = (s1 * 3 + s2) % max;
			s2 = (s1 + s2 + 33) % max;
			d = (double) s1 / max;
			b = (byte) java.lang.Math.floor((d * 31) + 64);
			chars[i] = (char) b;
		}
		return new String(chars);
	}

	static long[] newHash(String P) {
		long nr = 1345345333L;
		long add = 7;
		long nr2 = 0x12345671L;
		long tmp;
		for (int i = 0; i < P.length(); ++i) {
			if (P.charAt(i) == ' ' || P.charAt(i) == '\t')
				continue; // skip spaces
			tmp = (long) (0xff & P.charAt(i));
			nr ^= (((nr & 63) + add) * tmp) + (nr << 8);
			nr2 += (nr2 << 8) ^ nr;
			add += tmp;
		}
		long[] result = new long[2];
		result[0] = nr & 0x7fffffffL;
		result[1] = nr2 & 0x7fffffffL;
		return result;
	}

	static long oldHash(String P) {
		long nr = 1345345333;
		long nr2 = 7;
		long tmp;

		for (int i = 0; i < P.length(); i++) {
			if ((P.charAt(i) == ' ') || (P.charAt(i) == '\t'))
				continue;
			tmp = (long) P.charAt(i);
			nr ^= (((nr & 63) + nr2) * tmp) + (nr << 8);
			nr2 += tmp;
		}
		return nr & (((long) 1L << 31) - 1L);
	}

	/**
	 * Given a ResultSet and an index into the columns of that ResultSet,
	 * read binary data from the column which represents a serialized object,
	 * and re-create the object.
	 *
	 * @param RS the ResultSet to use.
	 * @param index an index into the ResultSet.
	 * @return the object if it can be de-serialized
	 * @throws Exception if an error occurs
	 */

	public static Object readObject(java.sql.ResultSet RS, int index)
		throws Exception {
		ObjectInputStream ObjIn = new ObjectInputStream(RS.getBinaryStream(index));
		Object O = ObjIn.readObject();
		ObjIn.close();

		return O;
	}
	
		
}