/**
 * Copyright (c) 2007-2014 Kaazing Corporation. All rights reserved.
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.kaazing.net.auth;

import java.util.Arrays;

/**
 * A challenge response contains a character array representing the response to the server,
 * and a reference to the next challenge handler to handle any further challenges for the request.
 *
 */
public class ChallengeResponse {

    private char[] credentials;
    private ChallengeHandler nextChallengeHandler;

    /**
     * Constructor from a set of credentials to send to the server in an 'Authorization:' header
     * and the next challenge handler responsible for handling any further challenges for the request.
     *
     * @param credentials a set of credentials to send to the server in an 'Authorization:' header
     * @param nextChallengeHandler the next challenge handler responsible for handling any further challenges for the request.
     */
    public ChallengeResponse(char[] credentials, ChallengeHandler nextChallengeHandler) {
        this.credentials = credentials;
        this.nextChallengeHandler = nextChallengeHandler;
    }

    /**
     * Return the next challenge handler responsible for handling any further challenges for the request.
     *
     * @return the next challenge handler responsible for handling any further challenges for the request.
     */
    public ChallengeHandler getNextChallengeHandler() {
        return nextChallengeHandler;
    }

    /**
     * Return a set of credentials to send to the server in an 'Authorization:' header.
     *
     * @return a set of credentials to send to the server in an 'Authorization:' header.
     */
    public char[] getCredentials() {
        return credentials;
    }

    /**
     * Establish the credentials for this response.
     *
     * @param credentials the credentials to be used for this challenge response.
     */
    public void setCredentials(char[] credentials) {
        this.credentials = credentials;
    }

    /**
     * Establish the next challenge handler responsible for handling any further challenges for the request.
     *
     * @param nextChallengeHandler the next challenge handler responsible for handling any further challenges for the request.
     */
    public void setNextChallengeHandler(ChallengeHandler nextChallengeHandler) {
        this.nextChallengeHandler = nextChallengeHandler;
    }

    /**
     * Clear the credentials of this response.
     * <p/>
     * Calling this method once the credentials have been communicated to the network layer
     * protects credentials in memory.
     */
    public void clearCredentials() {
        if (getCredentials() != null) {
                Arrays.fill(getCredentials(), (char) 0);
        }
    }
}