HORIZON PROJECT

var rng = require('./lib/rng');

var bytesToUuid = require('./lib/bytesToUuid');

function v4(options, buf, offset) {

  var i = buf && offset || 0;

  if (typeof(options) == 'string') {

    buf = options === 'binary' ? new Array(16) : null;

    options = null;

  }

  options = options || {};

  var rnds = options.random || (options.rng || rng)();

  // Per 4.4, set bits for version and `clock_seq_hi_and_reserved`

  rnds[6] = (rnds[6] & 0x0f) | 0x40;

  rnds[8] = (rnds[8] & 0x3f) | 0x80;

  // Copy bytes to buffer, if provided

  if (buf) {

    for (var ii = 0; ii < 16; ++ii) {

      buf[i + ii] = rnds[ii];

    }

  }

  return buf || bytesToUuid(rnds);

}

module.exports = v4;