Contents

module Podos
  class PokerHand < Deck
    def initialize cards
      raise 'doesnt have 5 cards' if cards.count != 5

      super cards
    end

    def rank
      return :royal_flush if royal_flush?
      return :straight_flush if straight_flush?
      return :four_of_a_kind if four_of_a_kind?
      return :full_house if full_house?
      return :flush if flush?
      return :straight if straight?
      return :two_pair if two_pair?
      return :pair if pair?
      :high_card
    end

    def royal_flush?
      return unless straight_flush?

      @cards.map(&:rank).max == 14
    end

    def straight_flush?
      straight? && flush?
    end

    def four_of_a_kind?
      card_counts_by_rank.include? 4
    end

    def full_house?
      pair? && three_of_a_kind?
    end

    def flush?
      @cards.group_by(&:suit).count == 1
    end

    def straight?
      return if card_counts_by_rank != [1,1,1,1,1]

      card_ranks = @cards.map(&:rank)

      (card_ranks.max - card_ranks.min) == 4
    end

    def three_of_a_kind?
      card_counts_by_rank.include? 3
    end

    def two_pair?
      card_counts_by_rank == [2,2,1].sort!
    end

    def pair?
      card_counts_by_rank.include? 2
    end

    protected

    def card_counts_by_rank
      @card_counts_by_rank ||= @cards.group_by(&:rank).values.map(&:count).sort!
    end
  end
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
podos-0.1.1	lib/podos/poker_hand.rb