/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is the Netscape Security Services for Java.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998-2000
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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package org.mozilla.jss.pkix.cmc;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.mozilla.jss.asn1.ASN1Template;
import org.mozilla.jss.asn1.ASN1Value;
import org.mozilla.jss.asn1.InvalidBERException;
import org.mozilla.jss.asn1.OCTET_STRING;
import org.mozilla.jss.asn1.SEQUENCE;
import org.mozilla.jss.asn1.Tag;
import org.mozilla.jss.pkix.primitive.AlgorithmIdentifier;

/**
 * CMC <i>PopLinkWitnessV2</i>:
 *   per rfc 5272
 * <pre>
 *     PopLinkWitnessV2 ::= SEQUENCE {
 *         keyGenAlgorithm     AlgorithmIdentifier,
 *         macAlgorithm       AlgorithmIdentifier,
 *         witness        OCTET STRING
 *     }
 * </pre>
 *
 * @author Christina Fu (cfu)
 */
public class PopLinkWitnessV2 implements ASN1Value {

    ///////////////////////////////////////////////////////////////////////
    // members and member access
    ///////////////////////////////////////////////////////////////////////
    private AlgorithmIdentifier keyGenAlgorithm;
    private AlgorithmIdentifier macAlgorithm;
    private OCTET_STRING witness;
    private SEQUENCE sequence;  // for DER encoding

    public AlgorithmIdentifier getKeyGenAlgorithm() {
        return keyGenAlgorithm;
    }

    public AlgorithmIdentifier getMacAlgorithm() {
        return macAlgorithm;
    }

    public OCTET_STRING getWitness() {
        return witness;
    }

    ///////////////////////////////////////////////////////////////////////
    // constructors
    ///////////////////////////////////////////////////////////////////////

    public PopLinkWitnessV2(
            AlgorithmIdentifier keyGenAlgorithm,
            AlgorithmIdentifier macAlgorithm,
            OCTET_STRING witness)
    {
        if(  keyGenAlgorithm==null || macAlgorithm==null ||
                witness==null ) {
            throw new IllegalArgumentException("PopLinkWitnessV2 constructor"
                +" parameter is null");
        }

        this.keyGenAlgorithm = keyGenAlgorithm;
        this.macAlgorithm = macAlgorithm;
        this.witness = witness;

        sequence = new SEQUENCE();
        sequence.addElement(keyGenAlgorithm);
        sequence.addElement(macAlgorithm);
        sequence.addElement(witness);
    }

    ///////////////////////////////////////////////////////////////////////
    // DER encoding
    ///////////////////////////////////////////////////////////////////////

    private static final Tag TAG = SEQUENCE.TAG;

    @Override
    public Tag getTag() {
        return TAG;
    }

    @Override
    public void encode(OutputStream ostream) throws IOException {
        sequence.encode(ostream);
    }

    @Override
    public void encode(Tag implicitTag, OutputStream ostream)
            throws IOException {
        sequence.encode(implicitTag, ostream);
    }

    private static final Template templateInstance = new Template();
    public static Template getTemplate() {
        return templateInstance;
    }

    /**
     * A Template for decoding BER-encoded PopLinkWitnessV2 items.
     */
    public static class Template implements ASN1Template {

        private SEQUENCE.Template seqt;

        public Template() {
            seqt = new SEQUENCE.Template();

            seqt.addElement( AlgorithmIdentifier.getTemplate() );
            seqt.addElement( AlgorithmIdentifier.getTemplate() );
            seqt.addElement( OCTET_STRING.getTemplate() );
        }

        @Override
        public boolean tagMatch(Tag tag) {
            return TAG.equals(tag);
        }

        @Override
        public ASN1Value decode(InputStream istream)
                throws InvalidBERException, IOException {
            return decode(TAG, istream);
        }

        @Override
        public ASN1Value decode(Tag implicitTag, InputStream istream)
                throws InvalidBERException, IOException {

            SEQUENCE seq = (SEQUENCE) seqt.decode(implicitTag, istream);

            return new PopLinkWitnessV2(
                            (AlgorithmIdentifier) seq.elementAt(0),
                            (AlgorithmIdentifier) seq.elementAt(1),
                            (OCTET_STRING) seq.elementAt(2) );
        }
    }
}
