module Tables
  class Swap
    private attr_reader :initial_solution
    def initialize(initial_solution)
      @initial_solution = initial_solution
    end

    def each
      @initial_solution.tables.combination(2) do |table_a, table_b|
        table_a.product(table_b).each do |(person_a, person_b)|
          table_a.delete(person_a)
          table_b.delete(person_b)

          table_a << person_b
          table_b << person_a

          yield(@initial_solution)
        ensure
          table_a.delete(person_b)
          table_b.delete(person_a)

          table_a << person_a
          table_b << person_b
        end
      end
    end
  end
end