pack puzzle

gistfile1.txt

exports.pack = (data, cb) ->
  ret= []
  innerRet = []
  for index, d of data
    if d then innerRet.push '1' else innerRet.push '0'
    if innerRet.length is 32 or index is (data.length - 1)
      ret.push innerRet
      innerRet = []

  binary = []
  for part in ret
    binaryStr = part.join('')
    binary.push parseInt binaryStr, 2
  binary.push data.length
  cb null, binary


exports.unpack = (buffer, cb) ->
  ret = ''
  arrayLength = buffer[buffer.length-1]
  for v in buffer[0..buffer.length-1]
    binaryStr = v.toString(2)
    if binaryStr.length < 32
      padding = '00000000000000000000000000000000'.substring 0, 32 - binaryStr.length
      binaryStr = padding + binaryStr
    ret += binaryStr

  ret = ret.substring 0, arrayLength
  data = []
  for v in ret
    if v is '1' then data.push true else data.push false

  cb null, data