module ZBase32

# File lib/zbase32.rb, line 18
def decode(bytes)
  join_string(bytes.downcase.split('').map { |s| ZB2N[s] })
end

# File lib/zbase32.rb, line 9
def encode(bytes)
  ret = ""
  (split_string(bytes)).each do |part|
    raise "There is no #{part}" unless part < 32
    ret = ret + CHARSET[part]
  end
  ret
end

# File lib/zbase32.rb, line 50
def join_string output
  length    = 5 * output.size
  ret       = Array.new((length / 8.0).ceil, 0)
  part      = 0  ; chunk  = 0
  suboffset = 0  ; offset = 0
  n         = 0  ; q      = 0
  while (q < length) do
    offset = (q / 8).to_i
    suboffset = q % 8
    part = output[n]
    chunk = (part << suboffset ) & MASKS[suboffset]
    ret[offset] |= chunk
    suboffset = suboffset - 4
    if suboffset >= 0
      ret[offset+1] |= (part >> (4-suboffset) ) & MASKS2[suboffset]
    end
    n = n + 1
    q = q + 5
  end
  string = ret.map(&:chr).join('')
  string.chomp!("\0")
  string
end

# File lib/zbase32.rb, line 24
def split_string string
  output    = [] ; chunk  = 0
  part      = 0  ; offset = 0
  suboffset = 0  ; q      = 0
  length    = 8 * string.length

  while (q < length) do
    offset = (q / 8).to_i
    suboffset = q % 8
    part = string[offset, 1][0].ord
    chunk = (part & MASKS[suboffset]) >> suboffset
    suboffset = suboffset - 4
    if suboffset >= 0
      if ((q + 5) > length)
        part = 0
      else
        part = string[offset+1, 1][0].ord
      end
      chunk |= (part & MASKS2[suboffset]) << (4 - suboffset)
    end
    output.push chunk
    q = q + 5
  end
  output
end