module Concerns::Domain::Transferable
  extend ActiveSupport::Concern

  included do
    after_initialize :generate_transfer_code, if: 'new_record? && transfer_code.blank?'
  end

  def transfer(new_registrar)
    old_registrar = registrar

    self.registrar = new_registrar
    regenerate_transfer_code

    contact_codes = contacts.pluck(:code).sort.uniq
    registrant_code = registrant.code

    transaction do
      old_registrar.messages.create!(
        body: I18n.t('domain_transfer_was_approved', contacts: contact_codes, registrant: registrant_code),
        attached_obj_id: id,
        attached_obj_type: self.class.name
      )

      domain_transfers.create!(
        transfer_requested_at: Time.zone.now,
        old_registrar: old_registrar,
        new_registrar: new_registrar
      )

      transfer_contacts(new_registrar)
      save!
    end
  end

  private

  def generate_transfer_code
    self.transfer_code = SecureRandom.hex
  end

  alias_method :regenerate_transfer_code, :generate_transfer_code

  def transfer_contacts(new_registrar)
    transfer_registrant(new_registrar)
    transfer_domain_contacts(new_registrar)
  end

  def transfer_registrant(new_registrar)
    return if registrant.registrar == new_registrar
    self.registrant = registrant.transfer(new_registrar)
  end

  def transfer_domain_contacts(new_registrar)
    copied_ids = []
    contacts.each do |contact|
      next if copied_ids.include?(contact.id) || contact.registrar == new_registrar

      if registrant_id_was == contact.id # registrant was copied previously, do not copy it again
        oc = OpenStruct.new(id: registrant_id)
      else
        oc = contact.transfer(new_registrar)
      end

      domain_contacts.where(contact_id: contact.id).update_all({ contact_id: oc.id }) # n+1 workaround
      copied_ids << contact.id
    end
  end
end