#!/usr/bin/env ruby

def hangman
  tries_left = 12
  # only select words less than ten letters long
  lines = File.readlines('/usr/share/dict/words').select { |e| e.length < 10 }
  # grab a random word
  word = lines[rand(lines.length)].chomp.chars
  guessed = []
  while tries_left > 0
    print "Guess a letter : "
    # only take the first character.
    # we could check to see if it's a letter, but why?
    guessed.push STDIN.gets.chomp.chars[0]
    # prints the letter or an underscore
    # the ternary could have been part of #reduce but the line is long enough as is
    puts word.
      map { |e| guessed.include?(e) ? e : '_'}.
      reduce('') { |acc, e| acc += " #{e} "}
    tries_left -= 1
    return puts "Congratulations! You win!" if word & guessed == word
    puts "You have #{tries_left} guesses left"
  end
  puts "Sorry, you lose. The word was #{word.join}"
end

loop do
  hangman
  print "Rematch? [y/N]"
  break unless gets.chomp.casecmp?('y')
end