Mongo binary UUID to Java legacy string and vice versa

uuid.coffee

{Binary} = require 'mongodb'

# Put together following https://github.com/mongodb/mongo-csharp-driver/blob/master/uuidhelpers.js
module.exports.toJUUID = toJUUID = (binId) ->
  return "" unless binId?.buffer?
  hex = binId.buffer.toString 'hex'
  msb = hex.substr(0, 16)
  lsb = hex.substr(16, 16)
  msb = msb.substr(14, 2) + msb.substr(12, 2) + msb.substr(10, 2) + msb.substr(8, 2) + msb.substr(6, 2) + msb.substr(4, 2) + msb.substr(2, 2) + msb.substr(0, 2)
  lsb = lsb.substr(14, 2) + lsb.substr(12, 2) + lsb.substr(10, 2) + lsb.substr(8, 2) + lsb.substr(6, 2) + lsb.substr(4, 2) + lsb.substr(2, 2) + lsb.substr(0, 2)
  hex = msb + lsb
  hex.substr(0, 8)  + '-' +
  hex.substr(8, 4)  + '-' +
  hex.substr(12, 4) + '-' +
  hex.substr(16, 4) + '-' +
  hex.substr(20, 12)

module.exports.toBinData = toBinData = (uuid) ->
  hex = uuid.replace /[{}-]/g, ""
  msb = hex.substr(0, 16);
  lsb = hex.substr(16, 16);
  msb = msb.substr(14, 2) + msb.substr(12, 2) + msb.substr(10, 2) + msb.substr(8, 2) + msb.substr(6, 2) + msb.substr(4, 2) + msb.substr(2, 2) + msb.substr(0, 2);
  lsb = lsb.substr(14, 2) + lsb.substr(12, 2) + lsb.substr(10, 2) + lsb.substr(8, 2) + lsb.substr(6, 2) + lsb.substr(4, 2) + lsb.substr(2, 2) + lsb.substr(0, 2);
  hex = msb + lsb;
  new Binary new Buffer(hex, 'hex'), Binary.SUBTYPE_UUID_OLD