/**
 * JS Implementation of MurmurHash2
 *
 * @author <a href="mailto:gary.court@gmail.com">Gary Court</a>
 * @see http://github.com/garycourt/murmurhash-js
 * @author <a href="mailto:aappleby@gmail.com">Austin Appleby</a>
 * @see http://sites.google.com/site/murmurhash/
 *
 * @param {string} str ASCII only
 * @return {int} hash result
 */
module.exports = function murmur2js(str) {
  var l = str.length;
  var h = l;
  var i = 0;
  var k;

  while (l >= 4) {
    k = ((str.charCodeAt(i) & 0xff)) |
      ((str.charCodeAt(++i) & 0xff) << 8) |
      ((str.charCodeAt(++i) & 0xff) << 16) |
      ((str.charCodeAt(++i) & 0xff) << 24);

    k = (((k & 0xffff) * 0x5bd1e995) + ((((k >>> 16) * 0x5bd1e995) & 0xffff) << 16));
    k ^= k >>> 24;
    k = (((k & 0xffff) * 0x5bd1e995) + ((((k >>> 16) * 0x5bd1e995) & 0xffff) << 16));

    h = (((h & 0xffff) * 0x5bd1e995) + ((((h >>> 16) * 0x5bd1e995) & 0xffff) << 16)) ^ k;

    l -= 4;
    ++i;
  }

  switch (l) {
    case 3: h ^= (str.charCodeAt(i + 2) & 0xff) << 16;
    case 2: h ^= (str.charCodeAt(i + 1) & 0xff) << 8;
    case 1: h ^= (str.charCodeAt(i) & 0xff);
      h = (((h & 0xffff) * 0x5bd1e995) + ((((h >>> 16) * 0x5bd1e995) & 0xffff) << 16));
  }

  h ^= h >>> 13;
  h = (((h & 0xffff) * 0x5bd1e995) + ((((h >>> 16) * 0x5bd1e995) & 0xffff) << 16));
  h ^= h >>> 15;

  return h >>> 0;
};
