/*****************************************************************************

 * md5.js

 *

 * A JavaScript implementation derived from the RSA Data Security, Inc. MD5

 * Message-Digest Algorithm. See http://cw.oaktree.co.uk/site/legal.html for

 * details.

 *

 * Copyright (C) Paul Johnston 1999 - 2000. Distributed under the LGPL.

 *****************************************************************************/



/* convert integer to hex string */

var sHex = "0123456789ABCDEF";

function hex(i)

{

  h = "";

  for(j = 0; j <= 3; j++)

  {

    h += sHex.charAt((i >> (j * 8 + 4)) & 0x0F) +

         sHex.charAt((i >> (j * 8)) & 0x0F);

  }

  return h;

}



/* add, handling overflows correctly */

function add(x, y)

{

  return ((x&0x7FFFFFFF) + (y&0x7FFFFFFF)) ^ (x&0x80000000) ^ (y&0x80000000);

}



/* MD5 rounds functions */

function R1(A, B, C, D, X, S, T)

{

  q = add(add(A, (B & C) | ((~B) & D)), add(X, T));

  return add((q << S) | (q >>> (32 - S)), B);

}



function R2(A, B, C, D, X, S, T)

{

  q = add(add(A, (B & D) | (C & (~D))), add(X, T));

  return add((q << S) | (q >>> (32 - S)), B);

}



function R3(A, B, C, D, X, S, T)

{

  q = add(add(A, B ^ C ^ D), add(X, T));

  return add((q << S) | (q >>> (32 - S)), B);

}



function R4(A, B, C, D, X, S, T)

{

  q = add(add(A, C ^ (B | (~D))), add(X, T));

  return add((q << S) | (q >>> (32 - S)), B);

}



/* main entry point */

function calcMD5(sInp) {



  /* Calculate length in machine words, including padding */

  wLen = (((sInp.length + 8) >> 6) + 1) << 4;

  var X = new Array(wLen);



  /* Convert string to array of words */

  j = 4;

  for (i = 0; (i * 4) < sInp.length; i++)

  {

    X[i] = 0;

    for (j = 0; (j < 4) && ((j + i * 4) < sInp.length); j++)

    {

      X[i] += sInp.charCodeAt(j + i * 4) << (j * 8);

    }

  }



  /* Append padding bits and length */

  if (j == 4)

  {

    X[i++] = 0x80;

  }

  else

  {

    X[i - 1] += 0x80 << (j * 8);

  }

  for(; i < wLen; i++) { X[i] = 0; }

  X[wLen - 2] = sInp.length * 8;



  /* hard coded initial values */

  a = 0x67452301;

  b = 0xefcdab89;

  c = 0x98badcfe;

  d = 0x10325476;



  /* Process each 16 word block in turn */

  for (i = 0; i < wLen; i += 16) {

    aO = a;

    bO = b;

    cO = c;

    dO = d;



    a = R1(a, b, c, d, X[i+ 0], 7 , 0xd76aa478);

    d = R1(d, a, b, c, X[i+ 1], 12, 0xe8c7b756);

    c = R1(c, d, a, b, X[i+ 2], 17, 0x242070db);

    b = R1(b, c, d, a, X[i+ 3], 22, 0xc1bdceee);

    a = R1(a, b, c, d, X[i+ 4], 7 , 0xf57c0faf);

    d = R1(d, a, b, c, X[i+ 5], 12, 0x4787c62a);

    c = R1(c, d, a, b, X[i+ 6], 17, 0xa8304613);

    b = R1(b, c, d, a, X[i+ 7], 22, 0xfd469501);

    a = R1(a, b, c, d, X[i+ 8], 7 , 0x698098d8);

    d = R1(d, a, b, c, X[i+ 9], 12, 0x8b44f7af);

    c = R1(c, d, a, b, X[i+10], 17, 0xffff5bb1);

    b = R1(b, c, d, a, X[i+11], 22, 0x895cd7be);

    a = R1(a, b, c, d, X[i+12], 7 , 0x6b901122);

    d = R1(d, a, b, c, X[i+13], 12, 0xfd987193);

    c = R1(c, d, a, b, X[i+14], 17, 0xa679438e);

    b = R1(b, c, d, a, X[i+15], 22, 0x49b40821);



    a = R2(a, b, c, d, X[i+ 1], 5 , 0xf61e2562);

    d = R2(d, a, b, c, X[i+ 6], 9 , 0xc040b340);

    c = R2(c, d, a, b, X[i+11], 14, 0x265e5a51);

    b = R2(b, c, d, a, X[i+ 0], 20, 0xe9b6c7aa);

    a = R2(a, b, c, d, X[i+ 5], 5 , 0xd62f105d);

    d = R2(d, a, b, c, X[i+10], 9 ,  0x2441453);

    c = R2(c, d, a, b, X[i+15], 14, 0xd8a1e681);

    b = R2(b, c, d, a, X[i+ 4], 20, 0xe7d3fbc8);

    a = R2(a, b, c, d, X[i+ 9], 5 , 0x21e1cde6);

    d = R2(d, a, b, c, X[i+14], 9 , 0xc33707d6);

    c = R2(c, d, a, b, X[i+ 3], 14, 0xf4d50d87);

    b = R2(b, c, d, a, X[i+ 8], 20, 0x455a14ed);

    a = R2(a, b, c, d, X[i+13], 5 , 0xa9e3e905);

    d = R2(d, a, b, c, X[i+ 2], 9 , 0xfcefa3f8);

    c = R2(c, d, a, b, X[i+ 7], 14, 0x676f02d9);

    b = R2(b, c, d, a, X[i+12], 20, 0x8d2a4c8a);



    a = R3(a, b, c, d, X[i+ 5], 4 , 0xfffa3942);

    d = R3(d, a, b, c, X[i+ 8], 11, 0x8771f681);

    c = R3(c, d, a, b, X[i+11], 16, 0x6d9d6122);

    b = R3(b, c, d, a, X[i+14], 23, 0xfde5380c);

    a = R3(a, b, c, d, X[i+ 1], 4 , 0xa4beea44);

    d = R3(d, a, b, c, X[i+ 4], 11, 0x4bdecfa9);

    c = R3(c, d, a, b, X[i+ 7], 16, 0xf6bb4b60);

    b = R3(b, c, d, a, X[i+10], 23, 0xbebfbc70);

    a = R3(a, b, c, d, X[i+13], 4 , 0x289b7ec6);

    d = R3(d, a, b, c, X[i+ 0], 11, 0xeaa127fa);

    c = R3(c, d, a, b, X[i+ 3], 16, 0xd4ef3085);

    b = R3(b, c, d, a, X[i+ 6], 23,  0x4881d05);

    a = R3(a, b, c, d, X[i+ 9], 4 , 0xd9d4d039);

    d = R3(d, a, b, c, X[i+12], 11, 0xe6db99e5);

    c = R3(c, d, a, b, X[i+15], 16, 0x1fa27cf8);

    b = R3(b, c, d, a, X[i+ 2], 23, 0xc4ac5665);



    a = R4(a, b, c, d, X[i+ 0], 6 , 0xf4292244);

    d = R4(d, a, b, c, X[i+ 7], 10, 0x432aff97);

    c = R4(c, d, a, b, X[i+14], 15, 0xab9423a7);

    b = R4(b, c, d, a, X[i+ 5], 21, 0xfc93a039);

    a = R4(a, b, c, d, X[i+12], 6 , 0x655b59c3);

    d = R4(d, a, b, c, X[i+ 3], 10, 0x8f0ccc92);

    c = R4(c, d, a, b, X[i+10], 15, 0xffeff47d);

    b = R4(b, c, d, a, X[i+ 1], 21, 0x85845dd1);

    a = R4(a, b, c, d, X[i+ 8], 6 , 0x6fa87e4f);

    d = R4(d, a, b, c, X[i+15], 10, 0xfe2ce6e0);

    c = R4(c, d, a, b, X[i+ 6], 15, 0xa3014314);

    b = R4(b, c, d, a, X[i+13], 21, 0x4e0811a1);

    a = R4(a, b, c, d, X[i+ 4], 6 , 0xf7537e82);

    d = R4(d, a, b, c, X[i+11], 10, 0xbd3af235);

    c = R4(c, d, a, b, X[i+ 2], 15, 0x2ad7d2bb);

    b = R4(b, c, d, a, X[i+ 9], 21, 0xeb86d391);



    a = add(a, aO);

    b = add(b, bO);

    c = add(c, cO);

    d = add(d, dO);

  }

  return hex(a) + hex(b) + hex(c) + hex(d);

}