rock paper scissors lizard spock

rpsls.rb

VALID_CHOICES = {
  'rock'     => %w(scissors lizard),
  'paper'    => %w(rock spock),
  'scissors' => %w(paper lizard),
  'lizard'   => %w(paper spock),
  'spock'    => %w(rock scissors)
}
last_player_choice = nil
strategy_modifier = rand(0.2..0.8)
player_score = 0
computer_score = 0
player_choice = ''

loop do
  loop do
    puts "Choose one: #{VALID_CHOICES.keys.join(', ')}"
    player_choice = gets.chomp
    break if VALID_CHOICES.keys.include?(player_choice)
    puts "That's not a valid choice."
  end

  computer_choice = last_player_choice && rand > strategy_modifier ? last_player_choice : VALID_CHOICES.keys.sample
  last_player_choice = player_choice

  puts "You chose: #{player_choice}; Computer chose: #{computer_choice}"

  if VALID_CHOICES[player_choice].include?(computer_choice)
    player_score += 1
    puts "You win!"
  elsif VALID_CHOICES[computer_choice].include?(player_choice)
    computer_score += 1
    puts "You lose!"
  else
    puts "It's a tie!"
  end

  break if player_score == 5 || computer_score == 5
end

puts "You #{player_score > computer_score ? 'WON' : 'LOST'} the match!"
puts "Your score was #{player_score} - #{computer_score}. Thank you for playing. Have a nice day!"