class Syllable
  def initialize
    @syllable_cache = Hash.new
  end

  def normalize(word)
	  return word.downcase.strip.tr('^a-z-\'','')
  end

  def syllables(word)
    word = word.downcase.strip.tr('^a-z-\'','')
    # caching syllables reduces average run time by more than half
    found = @syllable_cache[word]
    return found unless found.nil?

    subsyl = ["cial","tia","cius",
              "cious","giu",
              "ion","iou","sia$",".ely$", "ing"]

    addsyl = ["ia","riet","dien","iu",
              "io","ii","[aeiouym]bl$",
              "[aeiou]{3}",
              "^mc","ism$",
              '([^aeiouy])\1l$',
              "[^l]lien",
              "^coa[dglx].",
              "[^gq]ua[^auieo]",
              "dnt$"]

    # fold contraction
    word.tr!("'","")
    # chop off trailing 'e'
    word = word[0,word.length-1] if word[word.length-1,1] == "e"

    parts = word.split /[^aeiouy]+/
    parts.shift if parts[0] == ""
    count = 0
    # deal with exceptions
    subsyl.each{ |pat|
      count -= 1 if word =~ /#{pat}/
    }
    addsyl.each{ |pat|
      count += 1 if word =~ /#{pat}/
    }
    # x
    count += 1 if word.length == 1 && !vowel?(word)
    # count vowel groups
    count += parts.length
    count = 1 if count == 0

    @syllable_cache[word] = count
    return count
  end

end

s = Syllable.new
puts s.syllables("Should have a count of six") # Should give us 6
puts
puts s.syllables("Perhaps a more challenging test. The count should be fourteen") # Should give us 14