tennis_kata.rb

require 'rspec'

class Game
  attr_reader :player1, :player2
  POINTS = [0, 15, 30, 40]
  def initialize
    @player1 = Player.new('player1')
    @player2 = Player.new('player2')
    @point = Point.new(@player1, @player2)
    @score_view = ScoreView.new(@player1, @player2)
  end

  def score
    @score_view.render
  end

  def play_point
    @point.play
  end

  def play_game
    until winner
      puts score
      puts "#{play_point.name} wins point"
    end

    puts winner.name
  end

  def winner
    [@player1, @player2].find do |player|
      player_won?(player)
    end
  end

  def player_won?(player)
    player.points >= 4 &&
    player.points - 2 >= [@player1, @player2]
      .find { |p| p != player}.points
  end
end

class ScoreView
  POINTS = [0, 15, 30, 40]
  def initialize(player1, player2)
    @player1 = player1
    @player2 = player2
  end

  def render
    @player1.score <= 3 && @player2.score <= 3 ? regular_score : deuce_score
  end

  def player_in_lead
    @player1.score > @player2.score ? "player 1" : "player 2"
  end

  def regular_score
    "#{POINTS[@player1.score]} - #{POINTS[@player2.score]}"
  end

  def deuce_score
    @player1.score == @player2.score ? "deuce" : "ad #{player_in_lead}"
  end
end

class Point
  def initialize(player1, player2)
    @player1 = player1
    @player2 = player2
  end

  def play
    winner = [@player1, @player2].sample
    winner.add_point
    winner
  end
end


class Player
  attr_reader :points, :name
  def initialize(name)
    @name = name
    @points = 0
  end

  def add_point
    @points += 1
  end

  def score
    @points
  end
end

describe Game do
  before(:each) do
    @game = Game.new
  end

  context "before game starts" do
    it "score should be 0 - 0" do
      @game.score.should == "0 - 0"
    end

    it "winner should be nil" do
      @game.winner.should be_nil
    end
  end

  context "the score" do
    it "should be 15-0 after player 1 wins first point" do
      @game.log_point_winner(@game.player1)
      @game.score.should == "15 - 0"
    end

    it "should be up 30 - 0 after player 1 wins first two points" do
      2.times { @game.log_point_winner(@game.player1) }
      @game.score.should == "30 - 0"
    end

    it "should be 40 - 0 after player 1 wins first three points" do
      3.times { @game.log_point_winner(@game.player1) }
      @game.score.should == "40 - 0"
    end

    it "should be 0 - 15 after player 2 wins first point" do
      @game.log_point_winner(@game.player2)
      @game.score.should == "0 - 15"
    end

    context 'if at least one player has more than 3 points' do
      before(:each) do
        3.times { @game.log_point_winner(@game.player1) }
        3.times { @game.log_point_winner(@game.player2) }
      end

      it "should be deuce if players are tied" do
        @game.log_point_winner(@game.player1)
        @game.log_point_winner(@game.player2)
        @game.score.should == "deuce"
      end

      it "should be 'ad player 1' if player 1 is ahead" do
        @game.log_point_winner(@game.player1)
        @game.score.should == "ad player 1"
      end

      it "should be 'ad player 2' if player 2 is ahead" do
        @game.log_point_winner(@game.player2)
        @game.score.should == "ad player 2"
      end
    end

  end

  context "winner" do

    it "should be player 1 after winning first four points" do
      4.times { @game.log_point_winner(@game.player1) }
      @game.winner.should == @game.player1
    end

    it "should be player 2 after winning first four points" do
      4.times { @game.log_point_winner(@game.player2) }
      @game.winner.should == @game.player2
    end

    it "should not be declared after four points if opponent is less than two points behind" do
      3.times { 
        @game.log_point_winner(@game.player1) 
        @game.log_point_winner(@game.player2) 
      }

      @game.log_point_winner(@game.player1)
      @game.winner.should be_nil
    end

    it "should be declared after one player gets up by at least two" do
      3.times { 
        @game.log_point_winner(@game.player1) 
        @game.log_point_winner(@game.player2) 
      }

      @game.log_point_winner(@game.player2)

      3.times { @game.log_point_winner(@game.player1) }

      @game.winner.should == @game.player1
    end
  end
end

Game.new.play_game

#   context "when a player has scored" do
#     it "zero times, she has a score of 0" do
#       @game.player1.score.should == 0
#     end

#     it "one time, she has a score of 15" do
#       @game.player1.add_point
#       @game.player1.score.should == 15
#     end

#     it "two times, she has a score of 30" do
#       @game.player1.add_point
#       @game.player1.add_point
#       @game.player1.score.should == 30
#     end

#     it "three times, she has a score of 40" do
#       3.times { @game.player1.add_point }
#       @game.player1.score.should == 40
#     end

#   end
# end