/*
 * IzPack - Copyright 2001-2008 Julien Ponge, All Rights Reserved.
 * 
 * http://izpack.org/
 * http://izpack.codehaus.org/
 * 
 * Copyright 2003 Elmar Grom
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 *     
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.izforge.izpack.sample;

import com.izforge.izpack.panels.ProcessingClient;
import com.izforge.izpack.panels.Processor;

/*---------------------------------------------------------------------------*/
/**
 * This class provides a demonstration for using an encryption service in
 * connection with a password field, as used in a <code>UserInputPanel</code>.
 *
 * @author Elmar Grom
 * @version 0.0.1 / 02/19/03
 */
/*---------------------------------------------------------------------------*/
public class PWDEncryptor implements Processor
{
    /*--------------------------------------------------------------------------*/
    /**
     * Encrypts the a password and returns the encrypted result. <br>
     * <b>Note:</b> this is not a real encryption algorithm. The code only
     * demonstrates the use of this interface in a real installation environment.
     * For a real application a proper encryption mechanism must be used. Though
     * Java 1.4.X provides such algorithms, you need to consider that not all
     * potential target environments have this version installed. It seems best
     * to include the necessary encryption library with the installer.
     *
     * @param client the client object using the services of this encryptor.
     * @return the encryption result.
     */
    /*--------------------------------------------------------------------------*/
    public String process(ProcessingClient client)
    {
        if (client.getNumFields() < 1)
        {
            return ("");
        }

        char[] password = client.getFieldContents(0).toCharArray();
        char[] result = new char[password.length];
        int temp;

        for (int i = 0; i < password.length; i++)
        {
            temp = password[i] - 57;
            if (i > 0)
            {
                temp += password[i - 1];
            }

            if ((temp % 3) == 0)
            {
                temp += 13;
            }
            if (temp < 0)
            {
                temp += 193;
            }

            result[i] = (char) temp;
        }

        return (new String(result));
    }
}
/*---------------------------------------------------------------------------*/
