/*
 * Copyright (C) 2005-2008 Alfresco Software Limited.
 *
 * This program 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 2
 * of the License, or (at your option) any later version.

 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

 * As a special exception to the terms and conditions of version 2.0 of 
 * the GPL, you may redistribute this Program in connection with Free/Libre 
 * and Open Source Software ("FLOSS") applications as described in Alfresco's 
 * FLOSS exception.  You should have received a copy of the text describing 
 * the FLOSS exception, and it is also available here: 
 * http://www.alfresco.com/legal/licensing"
 */
package org.alfresco.util.security;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.SecureRandom;
import java.util.Arrays;

import junit.framework.TestCase;

/**
 * Tests that the EncryptingOutputStream and EncryptingInputStream classes work correctly.
 */
public class EncryptingOutputStreamTest extends TestCase
{

    /**
     * Tests encryption / decryption by attempting to encrypt and decrypt the bytes forming this class definition and
     * comparing it with the unencrypted bytes.
     * 
     * @throws Exception
     *             an exception
     */
    public void testEncrypt() throws Exception
    {
        final KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
        final SecureRandom random = SecureRandom.getInstance("SHA1PRNG");
        final byte[] seed = getClass().getName().getBytes("UTF-8");
        random.setSeed(seed);
        keyGen.initialize(1024, random);
        final KeyPair pair = keyGen.generateKeyPair();

        final ByteArrayOutputStream buff = new ByteArrayOutputStream(2048);
        final OutputStream encrypting = new EncryptingOutputStream(buff, pair.getPublic(), random);
        final ByteArrayOutputStream plainText1 = new ByteArrayOutputStream(2048);

        final InputStream in = getClass().getResourceAsStream(getClass().getSimpleName() + ".class");
        final byte[] inbuff = new byte[17];
        int bytesRead;
        while ((bytesRead = in.read(inbuff)) != -1)
        {
            encrypting.write(inbuff, 0, bytesRead);
            plainText1.write(inbuff, 0, bytesRead);
        }
        in.close();
        encrypting.close();
        plainText1.close();
        final InputStream decrypting = new DecryptingInputStream(new ByteArrayInputStream(buff.toByteArray()), pair
                .getPrivate());
        final ByteArrayOutputStream plainText2 = new ByteArrayOutputStream(2048);
        while ((bytesRead = decrypting.read(inbuff)) != -1)
        {
            plainText2.write(inbuff, 0, bytesRead);
        }

        assertTrue(Arrays.equals(plainText1.toByteArray(), plainText2.toByteArray()));

    }
}