pig_latin.rb

class PigLatin
  def self.translate(phrase)
    pig = PigLatin.new(phrase).convert
  end
  
  attr_reader :words
  
  def initialize(phrase)
    @words = phrase.split
  end
  
  def convert
    words.map do |word|
      if vowel_sound?(word)
        word + 'ay'
      else
        consonant_balance(word) + consonant(word) + 'ay'
      end
    end.join(' ')
  end
  
  def vowel_sound?(word)
    true if vowel?(word[0])
    case word[0] + word[1]
      when 'yt' then true
      when 'xr' then true
    end
  end
  
  def consonant_balance(word)
    word[consonant_end(word)..-1]
  end
  
  def consonant(word)
    word[0...consonant_end(word)]
  end
  
  def consonant_end(word)
    word.split('').each_with_index do |letter, index|
      return index if vowel?(letter)
      return index + 2 if letter == 'q'
    end
  end
  
  def vowel?(letter)
    %w(a e i o u).any? { |vowel| letter == vowel }
  end
end