flush_evaluator.rb

module RangeTools
  module FlushEvaluator
    extend self

    def evalFlush(twoCardHand, board)
      fullHand, board = prepareForFlush(twoCardHand, board)
      {
        fullHand: flushStrength(fullHand),
        board: flushStrength(board)
      }
    end

    private

    def flushStrength(hand)
      suitBuckets = buildSuitBuckets(hand)
      found = nil
      suitBuckets.each_pair do |suit, count|
        if count > 4
          found = :flush
        elsif count > 3
          found = :flush_draw
        end
      end
      found
    end

    def buildSuitBuckets(fullHand)
      fullHand.inject({}) do |suitBuckets, suit|
        suitBuckets[suit] ||= 0
        suitBuckets[suit] += 1
        suitBuckets
      end
    end

    def prepareForFlush(twoCardHand, board)
      twoCardHand = twoCardHand.collect {|card| card[:suit]}
      board = board.collect {|card| card[:suit]}
      fullHand = (twoCardHand + board)
      [fullHand, board]
    end
  end
end