rock-paper-scissors

get "/rps/:play" do
  rps_plays = ["rock", "paper", "scissors", "rock"]
  #outcomes = ["You win.", "You lose!", "It's a tie."]

  unless rps_plays.include?(params["play"])
    return "Try entering rock, paper, or scissors."
  end

  comp_play = rand(3)
  user_play = rps_plays.find_index(params["play"])

  if user_play == comp_play
    return "Computer played #{rps_plays[comp_play]}. It's a tie."
  elsif rps_plays[user_play] == rps_plays[comp_play + 1]
    return "Computer played #{rps_plays[comp_play]}. You win!"
  else
    return "Computer played #{rps_plays[comp_play]}. You lose."
  end
  
end