/**
 * $RCSfile: ,v $
 * $Revision: $
 * $Date: $
 * 
 * Copyright (C) 2004-2011 Jive Software. All rights reserved.
 *
 * 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 org.jivesoftware.sparkimpl.updater;

import javax.net.ssl.TrustManager;
import javax.net.ssl.TrustManagerFactory;
import javax.net.ssl.X509TrustManager;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import java.security.KeyStore;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;

/**
 * <p/>
 * EasyX509TrustManager unlike default {@link X509TrustManager} accepts
 * self-signed certificates.
 * </p>
 * <p/>
 * This trust manager SHOULD NOT be used for productive systems
 * due to security reasons, unless it is a concious decision and
 * you are perfectly aware of security implications of accepting
 * self-signed certificates
 * </p>
 *
 * @author <a href="mailto:adrian.sutton@ephox.com">Adrian Sutton</a>
 * @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
 *         <p/>
 *         <p/>
 *         DISCLAIMER: HttpClient developers DO NOT actively support this component.
 *         The component is provided as a reference material, which may be inappropriate
 *         for use without additional customization.
 *         </p>
 */

public class EasyX509TrustManager implements X509TrustManager {
    private X509TrustManager standardTrustManager = null;

    /**
     * Log object for this class.
     */
    private static final Log LOG = LogFactory.getLog(EasyX509TrustManager.class);

    public EasyX509TrustManager(KeyStore keystore) throws NoSuchAlgorithmException, KeyStoreException {
        super();
        TrustManagerFactory factory = TrustManagerFactory.getInstance("SunX509");
        factory.init(keystore);
        TrustManager[] trustmanagers = factory.getTrustManagers();
        if (trustmanagers.length == 0) {
            throw new NoSuchAlgorithmException("SunX509 trust manager not supported");
        }
        this.standardTrustManager = (X509TrustManager)trustmanagers[0];
    }

    public boolean isClientTrusted(X509Certificate[] certificates) {
        try {
            this.standardTrustManager.checkClientTrusted(certificates, null);
            return true;
        }
        catch (CertificateException e) {
            return false;
        }
    }

    public boolean isServerTrusted(X509Certificate[] certificates) {
        if ((certificates != null) && LOG.isDebugEnabled()) {
            LOG.debug("Server certificate chain:");
            for (int i = 0; i < certificates.length; i++) {
                LOG.debug("X509Certificate[" + i + "]=" + certificates[i]);
            }
        }
        if ((certificates != null) && (certificates.length == 1)) {
            X509Certificate certificate = certificates[0];
            try {
                certificate.checkValidity();
            }
            catch (CertificateException e) {
                LOG.error(e.toString());
                return false;
            }
            return true;
        }
        else {
            try {
                this.standardTrustManager.checkServerTrusted(certificates, null);
                return true;
            }
            catch (CertificateException e) {
                return false;
            }
        }
    }

    public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
    }

    public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException {
    }

    /**
     * @see javax.net.ssl.X509TrustManager#getAcceptedIssuers()
     */
    public X509Certificate[] getAcceptedIssuers() {
        return this.standardTrustManager.getAcceptedIssuers();
    }
}