Done

bin/tictactoe

@@ -1,3 +1,6 @@
 #!/usr/bin/env ruby
 
 require_relative '../config/environment'
+
+puts "Welcome to Tic Tac Toe!"
+Game.start

lib/board.rb

@@ -0,0 +1,61 @@
+require 'pry'
+
+class Board
+
+  attr_accessor :cells
+
+  def initialize
+    reset!
+  end
+
+  def display
+    puts " #{@cells[0]} | #{@cells[1]} | #{@cells[2]} \n-----------\n #{@cells[3]} | #{@cells[4]} | #{@cells[5]} \n-----------\n #{@cells[6]} | #{@cells[7]} | #{@cells[8]} "
+  end
+
+  def position(input)
+    @input = input.to_i - 1
+    @cells[@input]
+  end
+
+  def full?
+    if @cells.include? " "
+      false
+    else
+      true
+    end
+  end
+
+  def turn_count
+    @cells.count {|position| position != " "}
+  end
+
+  def taken?(position)
+    @position = position.to_i - 1
+    if ((@position >=0 && @position <= 8) && @cells[@position] != " ")
+      true
+    else
+      false
+    end
+  end
+
+  def valid_move?(position)
+    @position_taken = taken?(position)
+    @position = position.to_i - 1
+    if ((@position >=0 && @position <= 8) && !@position_taken)
+      true
+    else
+      false
+    end
+  end
+
+  def update(position,player)
+    @position = position.to_i - 1
+    @cells[@position] = player.token
+  end
+
+  def reset!
+    @cells = []
+    @cells = [" "," "," "," "," "," "," "," "," "]
+  end
+
+end

lib/game.rb

@@ -0,0 +1,146 @@
+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],[6,4,2]]
+
+  def initialize(player_1=nil, player_2=nil, board=nil)
+    player_1 == nil ? @player_1 = Players::Human.new("X") : @player_1 = player_1
+    player_2 == nil ? @player_2 = Players::Human.new("O") : @player_2 = player_2
+    board == nil ?  @board = Board.new : @board = board
+  end
+
+  def board
+    @board
+  end
+
+  def current_player
+    @board.turn_count % 2 == 0 ? @player_1 : @player_2
+  end
+
+  def won?
+    winner_found = false
+    WIN_COMBINATIONS.each do |combo|
+      tokens_played = combo.collect {|position| @board.cells[position]}
+      winner_found = combo if (tokens_played.all?("X") || tokens_played.all?("O"))
+    end
+    winner_found
+  end
+
+  def draw?
+    @board.full? && !won?
+  end
+
+  def over?
+    draw? || won?
+  end
+
+  def winner
+    if won?
+      @board.cells.count {|position| position == "X"} > @board.cells.count {|position| position == "O"} ? "X" : "O"
+    end
+  end
+
+  def turn
+    loop do
+      move = current_player.move(@board)
+
+      if move != "invalid"
+        @board.update(move, current_player)
+        move
+        break
+      end
+    end
+  end
+
+  def board_display
+    puts "Current board"
+
+    index = 0
+    board_string = ""
+
+    while index < 10
+      board_string += "| #{@board.cells[index]} "
+      board_string += "|\n" if index == 2 || index == 5
+      index += 1
+    end
+
+    puts board_string
+
+  end
+
+  def request_position
+    position_req = "Select an open square"
+    position_req += ", #{current_player.name}" if current_player.name != nil
+    position_req += ":"
+    puts position_req if current_player.class == Players::Human
+  end
+
+  def play
+
+    while !over?
+      request_position
+      board_display if current_player.class == Players::Human
+      turn
+    end
+    if winner != nil
+      puts "Congratulations #{winner}!"
+    elsif draw?
+      puts "Cat's Game!"
+    end
+  end
+
+  def self.start
+    puts "Please enter the number of players (0, 1, 2):"
+    player_count = gets.chomp
+
+    game_count = 1
+    won_count = 0
+
+    if player_count == "wargames"
+      puts "Thermonuclear War"
+      game_count = 100
+      @player_1 = Players::Computer.new("X")
+      @player_2 = Players::Computer.new("O")
+
+    elsif player_count == "0"
+      puts "You have asked for 2 Computer players."
+      @player_1 = Players::Computer.new("X")
+      @player_2 = Players::Computer.new("O")
+
+    elsif player_count == "1"
+      puts "You have asked for 1 Human player and 1 Computer player. Do you want X (Player 1) or 0 (Player 2)?"
+      human_token = gets.chomp
+
+      if human_token == "X"
+        @player_1 = Players::Human.new("X")
+        @player_2 = Players::Computer.new("O")
+      elsif human_token == "O"
+        @player_1 = Players::Computer.new("X")
+        @player_2 = Players::Human.new("O")
+      end
+
+    elsif player_count == "2"
+      puts "You have asked for a 2 Human player game. Who will be X (Player 1)?"
+      name1 = gets.chomp
+      puts "Who will be O (Player 2)?"
+      name2 = gets.chomp
+
+      @player_1 = Players::Human.new("X",name1)
+      @player_2 = Players::Human.new("O",name2)
+
+    end
+
+    while (game_count > 0 )
+      game = self.new(@player_1,@player_2)
+      game.play
+
+      won_count += 1 if game.winner != nil
+      game_count -= 1
+    end
+
+    puts "Outcome: #{won_count} games won."
+
+  end
+
+end

lib/player.rb

@@ -0,0 +1,10 @@
+class Player
+
+  attr_reader :token, :name
+
+  def initialize(token, name=nil)
+    @token = token
+    @name = name
+  end
+
+end

lib/players/computer.rb

@@ -0,0 +1,25 @@
+module Players
+
+  class Computer < Player
+
+    def move(board)
+
+      input = ""
+
+      if board.cells[4] == " " && board.cells.count {|cell| cell == " "} == 9 #middle square is empty and game is new
+        input = "5"
+      else
+        input = rand(1..9)
+      end
+
+      if !board.valid_move?(input)
+        input = "invalid"
+      end
+
+      input
+
+    end
+
+  end
+
+end

lib/players/human.rb

@@ -0,0 +1,17 @@
+module Players
+
+  class Human < Player
+
+    def move(board)
+
+      input = gets.chomp
+      if !board.valid_move?(input)
+        input = "invalid"
+      end
+
+      input
+    end
+
+  end
+
+end