/*
    * The MIT License
    *
    * Original work sponsored and donated by National Board of e-Health (NSI), Denmark (http://www.nsi.dk)
    *
    * Copyright (C) 2011 National Board of e-Health (NSI), Denmark (http://www.nsi.dk)
    *
    * Permission is hereby granted, free of charge, to any person obtaining a copy of
    * this software and associated documentation files (the "Software"), to deal in
   * the Software without restriction, including without limitation the rights to
   * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
   * of the Software, and to permit persons to whom the Software is furnished to do
   * so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in all
   * copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   *
   * $HeadURL: https://svn.softwareborsen.dk/sosi/trunk/modules/seal/src/main/java/dk/sosi/seal/xml/Base64.java $
   * $Id: Base64.java 8697 2011-09-02 10:33:55Z chg@lakeside.dk $
   */
  
  package dk.sosi.seal.xml;
  
  /**
   * This class provides encode/decode for RFC 2045 Base64 as defined by RFC 2045,
   * N. Freed and N. Borenstein. RFC 2045: Multipurpose Internet Mail Extensions
   * (MIME) Part One: Format of Internet Message Bodies. Reference 1996 Available
   * at: http://www.ietf.org/rfc/rfc2045.txt This class is used by XML Schema
   * binary format validation
   * 
   * This implementation does not encode/decode streaming data. You need the data
   * that you will encode/decode already on a byte arrray.
   * 
   * @author Jeffrey Rodriguez
   * @author Sandy Gao
   * @version $Id: Base64.java 8697 2011-09-02 10:33:55Z chg@lakeside.dk $
   */
  @Deprecated
  public final class Base64 { //NOPMD
  
  	static private final int BASELENGTH = 128;
  
  	static private final int LOOKUPLENGTH = 64;
  
  	static private final int TWENTYFOURBITGROUP = 24;
  
  	static private final int EIGHTBIT = 8;
  
  	static private final int SIXTEENBIT = 16;
  
  	static private final int FOURBYTE = 4;
  
  	static private final int SIGN = -128;
  
  	static private final char PAD = '=';
  
  	static final private byte[] base64Alphabet = new byte[BASELENGTH];
  
  	static final private char[] lookUpBase64Alphabet = new char[LOOKUPLENGTH];
  
  	static {
  
  		for (int i = 0; i < BASELENGTH; ++i) {
  			base64Alphabet[i] = -1;
  		}
  		for (int i = 'Z'; i >= 'A'; i--) {
  			base64Alphabet[i] = (byte) (i - 'A');
  		}
  		for (int i = 'z'; i >= 'a'; i--) {
  			base64Alphabet[i] = (byte) (i - 'a' + 26);
  		}
  
  		for (int i = '9'; i >= '0'; i--) {
  			base64Alphabet[i] = (byte) (i - '0' + 52);
  		}
  
  		base64Alphabet['+'] = 62;
  		base64Alphabet['/'] = 63;
  
  		for (int i = 0; i <= 25; i++)
  			lookUpBase64Alphabet[i] = (char) ('A' + i);
  
  		for (int i = 26, j = 0; i <= 51; i++, j++)
  			lookUpBase64Alphabet[i] = (char) ('a' + j);
  
  		for (int i = 52, j = 0; i <= 61; i++, j++)
  			lookUpBase64Alphabet[i] = (char) ('0' + j);
  		lookUpBase64Alphabet[62] = '+';
  		lookUpBase64Alphabet[63] = '/';
  
  	}
 
 	private static boolean isWhiteSpace(char octect) {
 		return (octect == 0x20 || octect == 0xd || octect == 0xa || octect == 0x9);
 	}
 
 	private static boolean isPad(char octect) {
 		return (octect == PAD);
 	}
 
 	private static boolean isData(char octect) {
 		return (octect < BASELENGTH && base64Alphabet[octect] != -1);
 	}
 
 	/**
 	 * Encodes hex octects into Base64
 	 * 
 	 * @param binaryData
 	 *            Array containing binaryData
 	 * @return Encoded Base64 array
 	 */
 	public static String encode(byte[] binaryData) {
 		if (binaryData == null || binaryData.length == 0)
 			return null;
 
 		int lengthDataBits = binaryData.length * EIGHTBIT;
 		int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
 		int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
 		int numberQuartet = fewerThan24bits != 0 ? numberTriplets + 1
 				: numberTriplets;
 		char encodedData[] = null;
 
 		encodedData = new char[numberQuartet * 4];
 
 		byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;
 
 		int encodedIndex = 0;
 		int dataIndex = 0;
 
 		for (int i = 0; i < numberTriplets; i++) {
 			b1 = binaryData[dataIndex++];
 			b2 = binaryData[dataIndex++];
 			b3 = binaryData[dataIndex++];
 
 			l = (byte) (b2 & 0x0f);
 			k = (byte) (b1 & 0x03);
 
 			byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2)
 					: (byte) ((b1) >> 2 ^ 0xc0);
 
 			byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4)
 					: (byte) ((b2) >> 4 ^ 0xf0);
 			byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6)
 					: (byte) ((b3) >> 6 ^ 0xfc);
 
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2) | val3];
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f];
 		}
 
 		// form integral number of 6-bit groups
 		if (fewerThan24bits == EIGHTBIT) {
 			b1 = binaryData[dataIndex];
 			k = (byte) (b1 & 0x03);
 			byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2)
 					: (byte) ((b1) >> 2 ^ 0xc0);
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[k << 4];
 			encodedData[encodedIndex++] = PAD;
 			encodedData[encodedIndex++] = PAD;
 		} else if (fewerThan24bits == SIXTEENBIT) {
 			b1 = binaryData[dataIndex];
 			b2 = binaryData[dataIndex + 1];
 			l = (byte) (b2 & 0x0f);
 			k = (byte) (b1 & 0x03);
 
 			byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2)
 					: (byte) ((b1) >> 2 ^ 0xc0);
 			byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4)
 					: (byte) ((b2) >> 4 ^ 0xf0);
 
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
 			encodedData[encodedIndex++] = lookUpBase64Alphabet[l << 2];
 			encodedData[encodedIndex++] = PAD;
 		}
 
 		return new String(encodedData);
 	}
 
 	/**
 	 * Decodes Base64 data into octects
 	 * 
 	 * @param encoded
 	 *            string containing Base64 data
 	 * @return Array containind decoded data.
 	 */
 	public static byte[] decode(String encoded) {
 
 		if (encoded == null)
 			return null;
 
 		char[] base64Data = encoded.toCharArray();
 		// remove white spaces
 		int len = removeWhiteSpace(base64Data);
 
 		if (len % FOURBYTE != 0) {
 			return null;// should be divisible by four
 		}
 
 		int numberQuadruple = (len / FOURBYTE);
 
 		if (numberQuadruple == 0)
 			return new byte[0];
 
 		byte decodedData[] = null;
 		byte b1 = 0, b2 = 0, b3 = 0, b4 = 0;
 		char d1 = 0, d2 = 0, d3 = 0, d4 = 0;
 
 		int i = 0;
 		int encodedIndex = 0;
 		int dataIndex = 0;
 		decodedData = new byte[(numberQuadruple) * 3];
 
 		for (; i < numberQuadruple - 1; i++) {
 
 			if (!isData((d1 = base64Data[dataIndex++]))
 					|| !isData((d2 = base64Data[dataIndex++]))
 					|| !isData((d3 = base64Data[dataIndex++]))
 					|| !isData((d4 = base64Data[dataIndex++])))
 				return null;// if found "no data" just return null
 
 			b1 = base64Alphabet[d1];
 			b2 = base64Alphabet[d2];
 			b3 = base64Alphabet[d3];
 			b4 = base64Alphabet[d4];
 
 			decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
 			decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
 			decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);
 		}
 
 		if (!isData((d1 = base64Data[dataIndex++]))
 				|| !isData((d2 = base64Data[dataIndex++]))) {
 			return null;// if found "no data" just return null
 		}
 
 		b1 = base64Alphabet[d1];
 		b2 = base64Alphabet[d2];
 
 		d3 = base64Data[dataIndex++];
 		d4 = base64Data[dataIndex++];
 		if (!isData((d3)) || !isData((d4))) {// Check if they are PAD
 												// characters
 			if (isPad(d3) && isPad(d4)) { // Two PAD e.g. 3c[Pad][Pad]
 				if ((b2 & 0xf) != 0)// last 4 bits should be zero
 					return null;
 				byte[] tmp = new byte[i * 3 + 1];
 				System.arraycopy(decodedData, 0, tmp, 0, i * 3);
 				tmp[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
 				return tmp;
 			} else if (!isPad(d3) && isPad(d4)) { // One PAD e.g. 3cQ[Pad]
 				b3 = base64Alphabet[d3];
 				if ((b3 & 0x3) != 0)// last 2 bits should be zero
 					return null;
 				byte[] tmp = new byte[i * 3 + 2];
 				System.arraycopy(decodedData, 0, tmp, 0, i * 3);
 				tmp[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
 				tmp[encodedIndex] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
 				return tmp;
 			} else {
 				return null;// an error like "3c[Pad]r", "3cdX", "3cXd", "3cXX"
 							// where X is non data
 			}
 		}
 
 		// No PAD e.g 3cQl
 		b3 = base64Alphabet[d3];
 		b4 = base64Alphabet[d4];
 		decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
 		decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
 		decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);
 
 		return decodedData;
 	}
 
 	/**
 	 * remove WhiteSpace from MIME containing encoded Base64 data.
 	 * 
 	 * @param data
 	 *            the byte array of base64 data (with WS)
 	 * @return the new length
 	 */
 	private static int removeWhiteSpace(char[] data) {
 		// count characters that's not whitespace
 		int newSize = 0;
 		int len = data.length;
 		for (int i = 0; i < len; i++) {
 			if (!isWhiteSpace(data[i]))
 				data[newSize++] = data[i];
 		}
 		return newSize;
 	}
 }