engine/app/models/extensions/site/subdomain_domains.rb

module Extensions
  module Site
    module SubdomainDomains

      def enable_subdomain_n_domains_if_multi_sites
        # puts "multi_sites? #{Locomotive.config.multi_sites?} / manage_domains? #{Locomotive.config.manage_domains?} / heroku? #{Locomotive.heroku?} / bushido? #{Locomotive.bushido?}"

        if Locomotive.config.multi_sites? || Locomotive.config.manage_domains?

          ## fields ##
          field :subdomain
          field :domains, :type => Array, :default => []

          ## indexes
          index :domains

          ## validations ##
          validates_presence_of     :subdomain
          validates_uniqueness_of   :subdomain
          validates_exclusion_of    :subdomain, :in => Locomotive.config.reserved_subdomains
          validates_format_of       :subdomain, :with => Locomotive::Regexps::SUBDOMAIN, :allow_blank => true
          validate                  :domains_must_be_valid_and_unique

          ## callbacks ##
          before_save :add_subdomain_to_domains

          ## named scopes ##
          scope :match_domain, lambda { |domain| { :any_in => { :domains => [*domain] } } }
          scope :match_domain_with_exclusion_of, lambda { |domain, site|
            { :any_in => { :domains => [*domain] }, :where => { :_id.ne => site.id } }
          }

          send :include, InstanceMethods
        end
      end

      module InstanceMethods

        def domains=(array)
          array = [] if array.blank?; super(array)
        end

        def add_subdomain_to_domains
          self.domains ||= []
          (self.domains << self.full_subdomain).uniq!
        end

        def domains_without_subdomain
          (self.domains || []) - [self.full_subdomain]
        end

        def domains_with_subdomain
          ((self.domains || []) + [self.full_subdomain]).uniq
        end

        def full_subdomain
          "#{self.subdomain}.#{Locomotive.config.domain}"
        end

        protected

        def domains_must_be_valid_and_unique
          return if self.domains.empty?

          self.domains_without_subdomain.each do |domain|
            if self.class.match_domain_with_exclusion_of(domain, self).any?
              self.errors.add(:domains, :domain_taken, :value => domain)
            end

            if not domain =~ Locomotive::Regexps::DOMAIN
              self.errors.add(:domains, :invalid_domain, :value => domain)
            end
          end
        end

      end

    end
  end
end