tictactoe.rb

require 'pry'

class Board
  attr_accessor :square

  def initialize
    create_board
  end

  def create_board
    square = {}
    1.upto(9) { |n| square[n] = Square.new }
    self.square = square
  end

  def empty_squares
    square.select { |_,v| v.mark == ' ' }.keys
  end
end

class Square
  attr_accessor :mark

  def initialize
    @mark = ' '
  end

  def to_s
    mark
  end
end

class Player
  attr_accessor :name

  def initialize
    set_name
  end
end

class Human < Player
  HUMAN_MARKER = 'X'

  def set_name
    puts 'Please enter your name:'
    answer = nil
    loop do
      answer = gets.chomp
      break unless answer.empty?
      puts 'Please enter a valid name.'
    end
    self.name = name
  end

  def turn!(board)
    puts "Choose a square from either #{board.empty_squares.join(', ')}:"
    answer = nil
    loop do
      answer = gets.chomp.to_i
      break if board.empty_squares.include?(answer)
      puts 'Please enter a valid number.'
    end
    board.square[answer] = HUMAN_MARKER
  end
end

class Computer < Player
  COMPUTER_MARKER = 'O'

  def set_name
    self.name = %w(Alex Cathrine Greg Rachel)
  end

  def turn!(board)
    # logic for computer to select a square
  end
end

class GameEngine
  attr_accessor :board, :human, :computer

  def initialize
    clear_screen
    @board = Board.new
    @human = Human.new
    @computer = Computer.new
  end

  def clear_screen
    system 'clear'
  end

  def display_board
    puts '     |     |     '
    puts "  #{board.square[1]}  |  #{board.square[2]}  |  #{board.square[3]}  "
    puts '     |     |     '
    puts '-----------------'
    puts '     |     |     '
    puts "  #{board.square[4]}  |  #{board.square[5]}  |  #{board.square[6]}  "
    puts '     |     |     '
    puts '-----------------'
    puts '     |     |     '
    puts "  #{board.square[7]}  |  #{board.square[8]}  |  #{board.square[9]}  "
    puts '     |     |     '
    puts ''
  end

  def play
    clear_screen
    loop do
      display_board
      human.turn!(board)
    end
    display_board
  end

end

GameEngine.new.play