Rank hands without tiebreaker

hand.rb

@@ -1,11 +1,19 @@
 require "./card"
+require "./hand_ranker"
 
 class Hand
   def initialize(cards)
     @cards = cards
+    @rank = HandRanker.new(self).rank
   end
 
+  attr_reader :rank, :cards
+
   def to_s
     @cards.join("\n")
   end
+
+  def <=>(other_hand)
+    rank <=> other_hand.rank
+  end
 end

hand_classifier.rb

@@ -0,0 +1,88 @@
+class HandClassifier
+  def initialize(hand)
+    @hand = hand
+  end
+
+  attr_reader :hand, :rank
+
+  def classify
+    if straight_flush?
+      :straight_flush
+    elsif four_of_a_kind?
+      :four_of_a_kind
+    elsif full_house?
+      :full_house
+    elsif flush?
+      :flush
+    elsif straight?
+      :straight
+    elsif three_of_a_kind?
+      :three_of_a_kind
+    elsif two_pair?
+      :two_pair
+    elsif one_pair?
+      :one_pair
+    else
+      :high_card
+    end
+  end
+
+  private
+
+  def straight_flush?
+    straight? && flush?
+  end
+
+  def four_of_a_kind?
+    find_pairings?(4)
+  end
+
+  def full_house?
+    grouped_hand = find_matches
+    full_house = grouped_hand.length == 2 && grouped_hand.any? do |group|
+      group.length == 2
+    end
+    full_house && grouped_hand.any?{ |group| group.length == 3 }
+  end
+
+  def flush?
+    hand.cards.map(&:suit).reduce(true, :==) #i apologize for the accidental obscenity of this code
+  end
+
+  def straight?
+    values = hand.cards.map(&:value)
+    values.sort!
+    increment = values[0]
+    match_tracker = true
+    values.each_with_index do |value, index|
+      match_tracker = match_tracker && index + increment == value
+    end
+    match_tracker
+  end
+
+  def three_of_a_kind?
+    find_pairings?(3)
+  end
+
+  def two_pair?
+    matches = find_pairings(2)
+    matches.length == 2
+  end
+
+  def one_pair?
+    find_pairings?(2)
+  end
+
+  def find_matches
+    hand.cards.group_by { |card| card.value }
+  end
+
+  def find_pairings?(length)
+    find_pairings(length).empty?
+  end
+
+  def find_pairings(length)
+    find_matches.select { |number, group| group.length == length }
+  end
+end
+

hand_ranker.rb

@@ -0,0 +1,31 @@
+require "./hand_classifier"
+class HandRanker
+  HAND_RANKS = {
+    straight_flush: 9,
+    four_of_a_kind: 8,
+    full_house: 7,
+    flush: 6,
+    straight: 5,
+    three_of_a_kind: 4,
+    two_pair: 3,
+    one_pair: 2,
+    high_card: 1
+  }
+
+  def initialize(hand)
+    @hand = hand
+    @rank = rank_hand
+  end
+
+  attr_reader :hand, :rank
+
+  def <=>(other_hand)
+      rank <=> other_hand.rank
+  end
+
+  private
+
+  def rank_hand
+    HAND_RANKS[HandClassifier.new(hand).classify]
+  end
+end

poker.rb

@@ -18,13 +18,16 @@ def deal_hands
   end
 
   def display_hands
+    puts "Hands ranked highest to lowest"
+    @hands.sort!.reverse!
     @hands.each_with_index do |hand, index|
       puts "Player #{index + 1}:"
       puts hand
+      puts hand.rank
       puts
     end
   end
 end
 
-poker = Poker.new(4)
+poker = Poker.new(6)
 poker.play