ANTS PROBLEM

ants_problem.rb

class Ant
  DIRECTIONS = [[1,0], [0,1], [-1,0], [0,-1]]   # [0]:right, [1]:bottom, [2]:left, [3]:top

  def in_border?
    (0 <= @position_x && @position_x < @size_x) && (0 <= @position_y && @position_y < @size_y)
  end

  def initialize(size, turns, middle = size/2)
    @matrix = Array.new(size) { Array.new(size, 'W') }

    @size_x, @size_y = size, size
    @position_x, @position_y = middle, middle

    @direction = 0
    @moves = 0

    while @moves < turns && in_border?
      @matrix.each.with_index do |row, idx|
        p row
        puts "\n" if idx == @size_x - 1
      end

      move
    end
  end

  def move
    @moves += 1

    @direction = (@matrix[@position_x][@position_y] == 'W' ? @direction + 1 : @direction - 1) % 4

    case @matrix[@position_x][@position_y]
    when 'B'
      @matrix[@position_x][@position_y] = 'W'
    when 'W'
      @matrix[@position_x][@position_y] = 'B'
    end

    @position_x += DIRECTIONS[@direction][0]
    @position_y += DIRECTIONS[@direction][1]
  end
end