A Yo-based communication system

yosup.rb

module SophSec
  module YoSup
    WORDS = %w{dawg sup hi yo}

    def YoSup.encode(message)
      encoded = []
      message = message.to_s

      message.each_byte do |b|
        encoded << WORDS[(b & 0x03)]
        encoded << WORDS[((b & 0x0c) >> 2)]
        encoded << WORDS[((b & 0x30) >> 4)]
        encoded << WORDS[((b & 0xc0) >> 6)]
      end

      return encoded.join(' ')
    end

    def YoSup.decode(message)
      decoded = ''

      lookup = lambda { |word|
        WORDS.index(word) || 0
      }

      message.gsub(/[\(\),;:\.\?]/,'').split(' ').each_slice(4) do |words|
        b = 0

        b |= lookup.call(words[0])
        b |= (lookup.call(words[1]) << 2)
        b |= (lookup.call(words[2]) << 4)
        b |= (lookup.call(words[3]) << 6)

        decoded << b.chr
      end

      return decoded
    end
  end
end