decorating_boards.rb

class Board
  def initialize ships
    @ships = ships
  end

  def shoot coordinates
     if coordinates == 1 # this would call the ships really
       @ships = [0,0,-1,1]
       return 'HIT'
     end
     return 'Miss'
  end

  def show
    @ships
  end
end

class OpponentBoard
  def initialize board
    @board = board
  end

  def shoot coordinates
    result = @board.shoot coordinates
  end
  def show
    @board.show.map do |n|
      if n > 0
        n-1
      else
        n
      end
    end
  end
end

class Player
  def initialize target
    @target = target
  end

  def shoot coordinates
    @target.shoot coordinates
  end

  def board
    @target.show
  end
end

board = Board.new [0,0,1,1]
target = OpponentBoard.new board
player = Player.new target
player.shoot 1
puts player.board.inspect