rock! scissors! you loose fat buddy.

rock_paper_scissors.rb

class WrongNumberOfPlayersError < StandardError ; end
class NoSuchStrategyError < StandardError ; end

def rps_result( first_strategy, second_strategy )
  worst_than = { "r"=>"s", "s"=>"p", "p"=>"r" }  # Hash of rock/paper/scissors rules
  worst_than[second_strategy[1].downcase] == first_strategy[1].downcase ? second_strategy : first_strategy
end

def rps_game_winner( game )
  raise WrongNumberOfPlayersError unless game.length == 2 
  raise NoSuchStrategyError unless game[0].length == 2 && game[1].length == 2
  raise NoSuchStrategyError unless game[0][1].downcase.match(/^[rps]$/) && game[1][1].downcase.match(/^[rps]$/)
    
  rps_result( game[0], game[1] )
end

def rps_tournament_winner( tournament )
  if tournament[0][0].is_a? String
    rps_game_winner tournament
  else
    rps_game_winner( [ rps_tournament_winner( tournament[0] ), rps_tournament_winner( tournament[1] ) ] )
  end 
end

def main
  
  # Testing winner of a single game
  single_game = [ [ "Armando", "P" ], [ "Dave", "S" ] ]
  puts rps_game_winner single_game
  
  # Testing winner of the all tournament !
  tournament = [
                  [
                    [ ["Armando", "P"], ["Dave", "S"] ],
                    [ ["Richard", "R"], ["Michael", "S"] ]
                  ],
                  [
                    [ ["Allen", "S"], ["Omer", "P"] ],
                    [ ["David E.", "R"], ["Richard X.", "P"] ]
                  ]
                ]
                
  puts rps_tournament_winner tournament
  
end