it3s/meppit

module Contributable
  extend ActiveSupport::Concern

  included do
    after_destroy :clean_contributings_for_destroyed_contributable!

    def contributors
      User.joins(:contributings).where(contributings: _contributable_params)
    end

    def contributors_count
      contributors.size
    end

    def add_contributor(contributor)
      contrib = Contributing.where(_contributable_params.merge contributor: contributor).first_or_create
      contrib.save
    end

    private

      def _contributable_params
        {contributable: self}
      end

      def clean_contributings_for_destroyed_contributable!
        Contributing.where(_contributable_params).destroy_all
      end
  end
end