// --- BEGIN COPYRIGHT BLOCK ---
// 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; version 2 of the License.
//
// 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.
//
// (C) 2007 Red Hat, Inc.
// All rights reserved.
// --- END COPYRIGHT BLOCK ---
package org.mozilla.jss.netscape.security.x509;

import java.io.IOException;

import org.mozilla.jss.netscape.security.util.BitArray;
import org.mozilla.jss.netscape.security.util.DerInputStream;
import org.mozilla.jss.netscape.security.util.DerOutputStream;
import org.mozilla.jss.netscape.security.util.DerValue;

/**
 * This class defines the UniqueIdentity class used by certificates.
 *
 * @author Amit Kapoor
 * @author Hemma Prafullchandra
 * @version 1.6
 */
public class UniqueIdentity {
    // Private data members
    private BitArray id;

    /**
     * The default constructor for this class.
     *
     * @param id the byte array containing the unique identifier.
     */
    public UniqueIdentity(BitArray id) {
        this.id = id;
    }

    /**
     * The default constructor for this class.
     *
     * @param id the byte array containing the unique identifier.
     */
    public UniqueIdentity(byte[] id) {
        this.id = new BitArray(id.length * 8, id);
    }

    /**
     * Create the object, decoding the values from the passed DER stream.
     *
     * @param in the DerInputStream to read the UniqueIdentity from.
     * @exception IOException on decoding errors.
     */
    public UniqueIdentity(DerInputStream in) throws IOException {
        DerValue derVal = in.getDerValue();
        id = derVal.getUnalignedBitString(true);
    }

    /**
     * Create the object, decoding the values from the passed DER stream.
     *
     * @param derVal the DerValue decoded from the stream.
     * @param tag the tag the value is encoded under.
     * @exception IOException on decoding errors.
     */
    public UniqueIdentity(DerValue derVal) throws IOException {
        id = derVal.getUnalignedBitString(true);
    }

    /**
     * Return the UniqueIdentity as a printable string.
     */
    public String toString() {
        return ("UniqueIdentity:" + id.toString() + "\n");
    }

    /**
     * Encode the UniqueIdentity in DER form to the stream.
     *
     * @param out the DerOutputStream to marshal the contents to.
     * @param tag enocode it under the following tag.
     * @exception IOException on errors.
     */
    public void encode(DerOutputStream out, byte tag) throws IOException {
        byte[] bytes = id.toByteArray();
        int excessBits = bytes.length * 8 - id.length();

        out.write(tag);
        out.putLength(bytes.length + 1);

        out.write(excessBits);
        out.write(bytes);
    }

    /**
     * Return the unique id.
     */
    public boolean[] getId() {
        if (id == null)
            return null;

        return id.toBooleanArray();
    }
}
