Class: TTT::MoveGenerator

Inherits:
Object
  • Object
show all
Defined in:
lib/tictactoe/move_generator.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(game) ⇒ MoveGenerator

Returns a new instance of MoveGenerator.



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# File 'lib/tictactoe/move_generator.rb', line 6

def initialize(game)
  @game = game
end

Instance Attribute Details

#choice ⇒ Object

Returns the value of attribute choice.



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# File 'lib/tictactoe/move_generator.rb', line 4

def choice
  @choice
end

#game ⇒ Object

Returns the value of attribute game.



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# File 'lib/tictactoe/move_generator.rb', line 4

def game
  @game
end

Instance Method Details

#minimax ⇒ Object 



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# File 'lib/tictactoe/move_generator.rb', line 15

def minimax
  scores = []
  choices = []
  if game.over?
    return score(game)
  end

  available_choices.each do |available_choice|
    new_game_state = Marshal.load(Marshal.dump(game))
    new_game_state.change_square(available_choice, game.current_player.value)
    #below needed because pry indicates possible_game_state's board not updating after make_move above
    # possible_game_state.game_board = possible_board_state
    choices.push(available_choice)
    new_move_generator = MoveGenerator.new(new_game_state)
    scores.push new_move_generator.minimax
  end

  if game.current_player == computer_player

    #https://stackoverflow.com/questions/2149802/in-ruby-what-is-the-cleanest-way-of-obtaining-the-index-of-the-largest-value-in
    max_score_index = scores.each_with_index.max[1]
    @choice = choices[max_score_index]
    return scores[max_score_index]
  else
    # This is the min calculation
    min_score_index = scores.each_with_index.min[1]
    @choice = choices[min_score_index]
    return scores[min_score_index]
  end

end

#random_move ⇒ Object

returns int representing display value of random available square



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# File 'lib/tictactoe/move_generator.rb', line 11

def random_move
  available_choices.sample
end