Done

bin/tictactoe

@@ -1,3 +1,5 @@
 #!/usr/bin/env ruby
 
-require_relative '../config/environment'
+require_relative '../config/environment'  # Loads environment and code
+
+Game.start.play

lib/board.rb

@@ -0,0 +1,65 @@
+require 'pry'
+class Board
+  attr_accessor :cells
+
+  def initialize
+    @cells = [" ", " ", " ", " ", " ", " ", " ", " ", " "]
+    # Commented out 8 & 9 and replaced with line 6. Not sure I need 8 & 9 anymore.
+    #@cells = []
+    #self.reset!
+  end
+
+  def reset!  #resets cells of the board to a 9 element array of " "
+    @cells.replace([" ", " ", " ", " ", " ", " ", " ", " ", " "]) #refactorMe
+  end
+
+  def display
+    puts " " + @cells[0] + " | " + @cells[1] + " | " + @cells[2] + " "
+    puts "-----------"
+    puts " " + @cells[3] + " | " + @cells[4] + " | " + @cells[5] + " "
+    puts "-----------"
+    puts " " + @cells[6] + " | " + @cells[7] + " | " + @cells[8] + " "
+  end
+
+  def position(user_input)  # takes in user input and returns the value of the board cell
+    self.cells[(user_input.to_i) - 1]
+  end
+
+  def full?
+    !self.cells.include?(" ")
+  end
+
+  def turn_count
+    count = 0
+    self.cells.each do |cell|
+      if cell != " "
+        count += 1
+      end
+    end
+    count
+  end
+
+  def taken?(position)
+    if @cells[position.to_i - 1] == "X"
+      true
+    elsif @cells[position.to_i - 1] == "O"
+      true
+    else
+      false
+    end
+  end
+
+  def valid_move?(user_input)
+    if taken?(user_input)
+      false
+    elsif !(1..9).include?(user_input.to_i)
+      false
+    else
+      true
+    end
+  end
+
+  def update(position, player)
+    @cells[position.to_i-1] = "#{player.token}"
+  end
+end

lib/game.rb

@@ -0,0 +1,92 @@
+class Game
+  attr_accessor :board, :player_1, :player_2
+
+  WIN_COMBINATIONS = [
+    [0, 1, 2],
+    [3, 4, 5],
+    [6, 7, 8],
+    [0, 3, 6],
+    [1, 4, 7],
+    [2, 5, 8],
+    [0, 4, 8],
+    [2, 4, 6]
+  ]
+
+  def initialize(player_1 = Players::Human.new("X"), player_2 = Players::Human.new("O"), board = Board.new)
+      @player_1 = player_1
+      @player_2 = player_2
+      @board = board
+  end
+
+  def current_player
+    (board.turn_count % 2) == 0 ? self.player_1 : self.player_2
+  end
+
+  def won?
+    WIN_COMBINATIONS.detect do |win_combo|
+      position_1 = board.cells[win_combo[0]]
+      position_2 = board.cells[win_combo[1]]
+      position_3 = board.cells[win_combo[2]]
+
+      position_1 == player_1.token && position_2 == player_1.token && position_3 == player_1.token || position_1 == player_2.token && position_2 == player_2.token && position_3 == player_2.token
+      end
+  end
+
+  def draw?
+    !won? && !board.cells.include?(" ")
+  end
+
+  def over?
+    won? || draw?
+  end
+
+  def winner
+    if winner = won?
+      board.cells[winner[0]]
+    end
+  end
+
+  def turn
+    board.display
+    input = current_player.move(board)
+    if board.valid_move?(input)
+      board.update(input, current_player)
+    else
+      puts "Invalid move. Please try again."
+      turn
+    end
+  end
+
+  def play
+    until over?
+      turn
+    end
+
+    if won?
+      puts "Congratulations #{winner}!"
+    else
+      puts "Cat's Game!"
+    end
+  end
+
+  def self.start
+    puts "Welcome to Tic Tac Toe!"
+    puts "How many players will be playing? Enter 0, 1, or 2"
+    number_of_players = gets.chomp
+    if number_of_players.to_i == 0
+          Game.new(player_1 = Players::Computer.new("X"), player_2 = Players::Computer.new("O"), board = Board.new)
+    elsif number_of_players.to_i == 1
+      puts "Would you like to be X and go first or be O and go second? Enter X or O"
+      player_choice = gets.chomp
+      if player_choice.capitalize == "X"
+        Game.new(player_1 = Players::Human.new("X"), player_2 = Players::Computer.new("O"), board = Board.new)
+      else
+        Game.new(player_1 = Players::Computer.new("X"), player_2 = Players::Human.new("O"), board = Board.new)
+      end
+    else
+      Game.new
+    end
+
+  end
+
+end

lib/player.rb

@@ -0,0 +1,8 @@
+class Player
+  attr_reader :token
+
+  def initialize(token)
+    @token = token
+  end
+
+end

lib/players/computer.rb

@@ -0,0 +1,15 @@
+module Players
+  class Computer < Player
+
+    def move(board)
+      puts "Computer select move 1 - 9"
+      if !board.taken?(5)
+        "5"
+      else
+       rand(1..9).to_s
+      end
+
+    end
+  end
+
+end

lib/players/human.rb

@@ -0,0 +1,10 @@
+module Players
+  class Human < Player
+
+    def move(board)
+      puts "Enter your move 1 - 9"
+      move = gets.chomp
+    end
+  end
+
+end