wedding-planner/app/services/tables/swap.rb

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)|
          new_solution = @initial_solution.dup

          new_table_a = table_a.dup
          new_table_b = table_b.dup

          new_solution.replace(new_table_a)
          new_solution.replace(new_table_b)

          new_table_a.delete(person_a)
          new_table_b.delete(person_b)

          new_table_a << person_b
          new_table_b << person_a

          new_solution.freeze

          yield(new_solution)
        end
      end
    end
  end
end