path: root/activerecord/lib/active_record/associations/has_one_through_association.rb

module ActiveRecord
  # = Active Record Has One Through Association
  module Associations
    class HasOneThroughAssociation < HasOneAssociation
      include ThroughAssociation

      def replace(record)
        create_through_record(record)
        self.target = record
      end

      private

      def create_through_record(record)
        through_proxy  = @owner.send(:association_proxy, @reflection.through_reflection.name)
        through_record = through_proxy.send(:load_target)

        if through_record && !record
          through_record.destroy
        elsif record
          attributes = construct_join_attributes(record)

          if through_record
            through_record.update_attributes(attributes)
          elsif @owner.new_record?
            through_proxy.build(attributes)
          else
            through_proxy.create(attributes)
          end
        end
      end
    end
  end
end