openreplay/tracker/tracker-redux/src/syncod-v2/mur.ts

function murmurhash3_32_rp(key, seed) {
  var keyLength, tailLength, tailLength4, bodyLength, bodyLength8, h1, k1, i, c1_low, c1_high, c2_low, c2_high, k1B, c3;
  keyLength = key.length;
  tailLength = keyLength & 3;
  bodyLength = keyLength - tailLength;
  tailLength4 = bodyLength & 7;
  bodyLength8 = bodyLength - tailLength4;
  h1 = seed;

  //c1 = 0xcc9e2d51;
  c1_low = 0x2d51;
  c1_high = 0xcc9e0000;

  //c2 = 0x1b873593;
  c2_low = 0x3593;
  c2_high = 0x1b870000;

  c3 = 0xe6546b64;


  //----------
  // body

  i = 0;

  while (i < bodyLength8) {

    k1 =
      ((key.charCodeAt(i) & 0xff)) |
      ((key.charCodeAt(++i) & 0xff) << 8) |
      ((key.charCodeAt(++i) & 0xff) << 16) |
      ((key.charCodeAt(++i) & 0xff) << 24);

    k1B =
      ((key.charCodeAt(++i) & 0xff)) |
      ((key.charCodeAt(++i) & 0xff) << 8) |
      ((key.charCodeAt(++i) & 0xff) << 16) |
      ((key.charCodeAt(++i) & 0xff) << 24);

    ++i;


    //k1 *= c1;
    k1 = (c1_high * k1 | 0) + (c1_low * k1);
    //k1 = ROTL32(k1,15);
    k1 = (k1 << 15) | (k1 >>> 17);
    //k1 *= c2;
    k1 = (c2_high * k1 | 0) + (c2_low * k1);

    //h1 ^= k1;
    h1 ^= k1;
    //h1 = ROTL32(h1,13);
    h1 = (h1 << 13) | (h1 >>> 19);
    //h1 = h1*5+0xe6546b64;
    h1 = h1 * 5 + c3;


    //k1 *= c1;
    k1B = (c1_high * k1B | 0) + (c1_low * k1B);
    //k1 = ROTL32(k1,15);
    k1B = (k1B << 15) | (k1B >>> 17);
    //k1 *= c2;
    k1B = (c2_high * k1B | 0) + (c2_low * k1B);

    //h1 ^= k1;
    h1 ^= k1B;
    //h1 = ROTL32(h1,13);
    h1 = (h1 << 13) | (h1 >>> 19);
    //h1 = h1*5+0xe6546b64;
    h1 = h1 * 5 + c3;

  }   //while (i < bodyLength8) {


  if (tailLength4) {

    k1 =
      ((key.charCodeAt(i) & 0xff)) |
      ((key.charCodeAt(++i) & 0xff) << 8) |
      ((key.charCodeAt(++i) & 0xff) << 16) |
      ((key.charCodeAt(++i) & 0xff) << 24);

    ++i;

    //k1 *= c1;
    k1 = (c1_high * k1 | 0) + (c1_low * k1);
    //k1 = ROTL32(k1,15);
    k1 = (k1 << 15) | (k1 >>> 17);
    //k1 *= c2;
    k1 = (c2_high * k1 | 0) + (c2_low * k1);

    //h1 ^= k1;
    h1 ^= k1;
    //h1 = ROTL32(h1,13);
    h1 = (h1 << 13) | (h1 >>> 19);
    //h1 = h1*5+0xe6546b64;
    h1 = h1 * 5 + c3;

  }   //if (tailLength4) {


  //----------
  // tail

  k1 = 0;

  switch (tailLength) {

    case 3: k1 ^= (key.charCodeAt(i + 2) & 0xff) << 16;
    case 2: k1 ^= (key.charCodeAt(i + 1) & 0xff) << 8;
    case 1: k1 ^= (key.charCodeAt(i) & 0xff);

      //k1 *= c1;
      k1 = (c1_high * k1 | 0) + (c1_low * k1);
      //k1 = ROTL32(k1,15);
      k1 = (k1 << 15) | (k1 >>> 17);
      //k1 *= c2;
      k1 = (c2_high * k1 | 0) + (c2_low * k1);
      //h1 ^= k1;
      h1 ^= k1;

  }   //switch (tailLength) {


  //----------
  // finalization

  h1 ^= keyLength;

  //h1 = fmix32(h1);
  {
    //h ^= h >> 16;
    h1 ^= h1 >>> 16;
    //h1 *= 0x85ebca6b;
    h1 = (0x85eb0000 * h1 | 0) + (0xca6b * h1);
    //h ^= h >> 13;
    h1 ^= h1 >>> 13;
    //h1 *= 0xc2b2ae35;
    h1 = (0xc2b20000 * h1 | 0) + (0xae35 * h1);
    //h ^= h >> 16;
    h1 ^= h1 >>> 16;
  }


  return h1 >>> 0;    //convert to unsigned int

}


function murmurHash3ToBase64(key, seed = 0) {
  let hashValue = murmurhash3_32_rp(key, seed);
  return hashToBase64(hashValue);
}

function hashToBase64(hash) {
  let buffer = new ArrayBuffer(4); // 32 bits for hash
  let view = new DataView(buffer);
  view.setUint32(0, hash, false); // Use big-endian
  return btoa(String.fromCharCode.apply(null, new Uint8Array(buffer)));
}

export default murmurHash3ToBase64;