How to metaprogram routes dinamicaly?

Question

So there should be a class called Registers::Internal::Routes with a class method called draw that takes a block as a parameter:

def self.draw(&block)
  ...
end

It should be possible to pass the structures of the routes in this block. Example:

Registers::Internal::Routes.draw do
  namespace :api do
    namespace :internal do
      namespace :companies do
        resources :registrations, only: [:index, :show] do
          post :request

          member do
            post :cancel
          end

          resources :bank_accounts, only: :index
        end
      end
    end
  end
end

it should be possible to acquire the URL of the routes, for example:

Registers::Internal::Routes.api_internal_companies_registrations_url
# api/internal/companies/registrations

Registers::Internal::Routes.api_internal_companies_registration_url("aef54ea9-239c-42c7-aee7-670a0d454f1d")
# api/internal/companies/registrations/aef54ea9-239c-42c7-aee7-670a0d454f1d

Registers::Internal::Routes.api_internal_companies_registrations_request_url
# api/internal/companies/registrations/request

Registers::Internal::Routes.api_internal_companies_registration_cancel_url("aef54ea9-239c-42c7-aee7-670a0d454f1d")
# api/internal/companies/registrations/aef54ea9-239c-42c7-aee7-670a0d454f1d/cancel

Registers::Internal::Routes.api_internal_companies_registration_bank_accounts_url("aef54ea9-239c-42c7-aee7-670a0d454f1d")
# api/internal/companies/registrations/aef54ea9-239c-42c7-aee7-670a0d454f1d/bank_accounts

---

So after playing a bit with this, i "managed" to try to generate an "url" everytime the namespace/resources/member/post method is called, the problem is that the "url" variable doesnt reset, therefore resulting in it being overwritten. Is there any other way to do this, simple and cleaner?

module Registers
  module Internal
    class Routes
      def self.draw(&block)
        @url = ""
        class_eval(&block)
      end

      def self.namespace(key, &block)
        generate_url("namespace", key)
        class_eval(&block)
      end

      def self.resources(key, options, &block)
        generate_url("resources", key, options)
        class_eval(&block) if block_given?
      end

      def self.member(&block)
        class_eval(&block)
      end

      def self.post(action)
        generate_url("action", action)
      end

      def self.generate_url(name, key, options = nil)
        if name != "action"
          @url << "#{key.to_s + '/'}"
        else
          @url << "/#{key.to_s}"
          define_class_method(@url)
        end
        set_options(options) if options.present?
      end

      def self.set_options(options)
        Array(options[:only]).each do |option|
          case option
          when :index
            @url.chop!
          when :show
            @url
          end
          define_class_method(@url)
        end
      end

      def self.define_class_method(url)
        method_name = "#{url.gsub('/', '_')}_url".to_sym
        self.class.instance_eval do
          define_method(method_name) do
            url
          end
        end
      end
    end
  end
end