var hash = require('../hash');
var utils = hash.utils;

var rotl32 = utils.rotl32;
var sum32 = utils.sum32;
var sum32_3 = utils.sum32_3;
var sum32_4 = utils.sum32_4;
var BlockHash = hash.common.BlockHash;

function RIPEMD160() {
  if (!(this instanceof RIPEMD160))
    return new RIPEMD160();

  BlockHash.call(this);

  this.h = [ 0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0 ];
  this.endian = 'little';
}
utils.inherits(RIPEMD160, BlockHash);
exports.ripemd160 = RIPEMD160;

RIPEMD160.blockSize = 512;
RIPEMD160.outSize = 160;
RIPEMD160.hmacStrength = 192;
RIPEMD160.padLength = 64;

RIPEMD160.prototype._update = function update(msg, start) {
  var A = this.h[0];
  var B = this.h[1];
  var C = this.h[2];
  var D = this.h[3];
  var E = this.h[4];
  var Ah = A;
  var Bh = B;
  var Ch = C;
  var Dh = D;
  var Eh = E;
  for (var j = 0; j < 80; j++) {
    var T = sum32(
      rotl32(
        sum32_4(A, f(j, B, C, D), msg[r[j] + start], K(j)),
        s[j]),
      E);
    A = E;
    E = D;
    D = rotl32(C, 10);
    C = B;
    B = T;
    T = sum32(
      rotl32(
        sum32_4(Ah, f(79 - j, Bh, Ch, Dh), msg[rh[j] + start], Kh(j)),
        sh[j]),
      Eh);
    Ah = Eh;
    Eh = Dh;
    Dh = rotl32(Ch, 10);
    Ch = Bh;
    Bh = T;
  }
  T = sum32_3(this.h[1], C, Dh);
  this.h[1] = sum32_3(this.h[2], D, Eh);
  this.h[2] = sum32_3(this.h[3], E, Ah);
  this.h[3] = sum32_3(this.h[4], A, Bh);
  this.h[4] = sum32_3(this.h[0], B, Ch);
  this.h[0] = T;
};

RIPEMD160.prototype._digest = function digest(enc) {
  if (enc === 'hex')
    return utils.toHex32(this.h, 'little');
  else
    return utils.split32(this.h, 'little');
};

function f(j, x, y, z) {
  if (j <= 15)
    return x ^ y ^ z;
  else if (j <= 31)
    return (x & y) | ((~x) & z);
  else if (j <= 47)
    return (x | (~y)) ^ z;
  else if (j <= 63)
    return (x & z) | (y & (~z));
  else
    return x ^ (y | (~z));
}

function K(j) {
  if (j <= 15)
    return 0x00000000;
  else if (j <= 31)
    return 0x5a827999;
  else if (j <= 47)
    return 0x6ed9eba1;
  else if (j <= 63)
    return 0x8f1bbcdc;
  else
    return 0xa953fd4e;
}

function Kh(j) {
  if (j <= 15)
    return 0x50a28be6;
  else if (j <= 31)
    return 0x5c4dd124;
  else if (j <= 47)
    return 0x6d703ef3;
  else if (j <= 63)
    return 0x7a6d76e9;
  else
    return 0x00000000;
}

var r = [
  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
  7, 4, 13, 1, 10, 6, 15, 3, 12, 0, 9, 5, 2, 14, 11, 8,
  3, 10, 14, 4, 9, 15, 8, 1, 2, 7, 0, 6, 13, 11, 5, 12,
  1, 9, 11, 10, 0, 8, 12, 4, 13, 3, 7, 15, 14, 5, 6, 2,
  4, 0, 5, 9, 7, 12, 2, 10, 14, 1, 3, 8, 11, 6, 15, 13
];

var rh = [
  5, 14, 7, 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12,
  6, 11, 3, 7, 0, 13, 5, 10, 14, 15, 8, 12, 4, 9, 1, 2,
  15, 5, 1, 3, 7, 14, 6, 9, 11, 8, 12, 2, 10, 0, 4, 13,
  8, 6, 4, 1, 3, 11, 15, 0, 5, 12, 2, 13, 9, 7, 10, 14,
  12, 15, 10, 4, 1, 5, 8, 7, 6, 2, 13, 14, 0, 3, 9, 11
];

var s = [
  11, 14, 15, 12, 5, 8, 7, 9, 11, 13, 14, 15, 6, 7, 9, 8,
  7, 6, 8, 13, 11, 9, 7, 15, 7, 12, 15, 9, 11, 7, 13, 12,
  11, 13, 6, 7, 14, 9, 13, 15, 14, 8, 13, 6, 5, 12, 7, 5,
  11, 12, 14, 15, 14, 15, 9, 8, 9, 14, 5, 6, 8, 6, 5, 12,
  9, 15, 5, 11, 6, 8, 13, 12, 5, 12, 13, 14, 11, 8, 5, 6
];

var sh = [
  8, 9, 9, 11, 13, 15, 15, 5, 7, 7, 8, 11, 14, 14, 12, 6,
  9, 13, 15, 7, 12, 8, 9, 11, 7, 7, 12, 7, 6, 15, 13, 11,
  9, 7, 15, 11, 8, 6, 6, 14, 12, 13, 5, 14, 13, 13, 7, 5,
  15, 5, 8, 11, 14, 14, 6, 14, 6, 9, 12, 9, 12, 5, 15, 8,
  8, 5, 12, 9, 12, 5, 14, 6, 8, 13, 6, 5, 15, 13, 11, 11
];