/*************************************************************************
 *                                                                       *
 *  CERT-CVC: EAC 1.11 Card Verifiable Certificate Library               * 
 *                                                                       *
 *  This software is free software; you can redistribute it and/or       *
 *  modify it under the terms of the GNU Lesser General Public           *
 *  License as published by the Free Software Foundation; either         *
 *  version 2.1 of the License, or any later version.                    *
 *                                                                       *
 *  See terms of license at gnu.org.                                     *
 *                                                                       *
 *************************************************************************/
package org.ejbca.cvc;

import java.math.BigInteger;

import org.ejbca.cvc.util.StringConverter;

/**
 * Generic field representing binary data (or Octet String)
 * 
 * @author Keijo Kurkinen, Swedish National Police Board
 * @version $Id: ByteField.java 20720 2015-02-19 16:56:59Z mikekushner $
 *
 */
public class ByteField extends AbstractDataField {

    private static final long serialVersionUID = 1L;
    private byte[] data;
    private boolean showBitLength = false;

    /**
     * Constructor taking tag
     * 
     * @param tag
     */
    ByteField(CVCTagEnum tag) {
	super(tag);
    }

    /**
     * Constructor taking tag and data
     * 
     * @param tag
     * @param data
     */
    ByteField(CVCTagEnum tag, byte[] data) {
	this(tag, data, false);
    }

    /**
     * Constructor taking tag, data and flag indicating if data length should be
     * shown in valueAsText()
     * 
     * @param tag
     * @param data
     * @param showBitLength
     */
    ByteField(CVCTagEnum tag, byte[] data, boolean showBitLength) {
	super(tag);
	this.data = data;
	this.showBitLength = showBitLength;
    }

    /**
     * Returns flag for 'showBitLen'
     * 
     * @return
     */
    public boolean isShowBitLength() {
	return showBitLength;
    }

    /**
     * Sets flag 'showBitLen'
     * 
     * @param showBitLength
     *            - if true then valueAsText() will add an entry showing the length
     *            in bits
     */
    public void setShowBitLength(boolean showBitLength) {
	this.showBitLength = showBitLength;
    }

    /**
     * Returns the data.
     * 
     * @return
     */
    public byte[] getData() {
	return data;
    }

    @Override
    protected byte[] getEncoded() {
	return data;
    }

    @Override
    protected String valueAsText() {
	String lenInfo = "";
	// Check if length in bits should be shown
	if (showBitLength) {
	    int bitLength = 0;
	    if (data != null) {
		BigInteger big = new BigInteger(1, data);
		bitLength = big.bitLength();
	    }
	    lenInfo = "[" + bitLength + "]  ";
	}
	return lenInfo + StringConverter.byteToHex(data);
    }

}