module Federails
  module Entity
    extend ActiveSupport::Concern

    included do # rubocop:todo Metrics/BlockLength
      include ActiveSupport::Callbacks
      define_callbacks :followed

      # Define a method that will be called after the entity receives a follow request
      # @param method [Symbol] The name of the method to call, or a block that will be called directly
      # @example
      #   after_followed :accept_follow
      def self.after_followed(method)
        set_callback :followed, :after, method
      end

      # Define a method that will be called after an activity has been received
      # @param activity_type [String] The activity action to handle, e.g. 'Create'. If you specify '*', the handler will be called for any activity type.
      # @param object_type [String] The object type to handle, e.g. 'Note'. If you specify '*', the handler will be called for any object type.
      # @param method [Symbol] The name of the class method to call. The method will receive the complete activity payload as a parameter.
      # @example
      #   after_activity_received 'Create', 'Note', :create_note
      def self.after_activity_received(activity_type, object_type, method)
        Fediverse::Inbox.register_handler(activity_type, object_type, self, method)
      end

      has_one :actor, class_name: 'Federails::Actor', as: :entity, dependent: :destroy

      after_create :create_actor, if: lambda {
        raise("Entity not configured for #{self.class.name}. Did you use \"acts_as_federails_actor\"?") unless Federails::Configuration.entity_types.key? self.class.name

        Federails::Configuration.entity_types[self.class.name][:auto_create_actors]
      }

      # Configures the mapping between entity and actor
      # @param username_field [Symbol] The method or attribute name that returns the preferred username for ActivityPub
      # @param name_field [Symbol] The method or attribute name that returns the preferred name for ActivityPub
      # @param profile_url_method [Symbol] The route method name that will generate the profile URL for ActivityPub
      # @param actor_type [String] The ActivityStreams Actor type for this entity; defaults to 'Person'
      # @param user_count_method [Symbol] A class method to call to count active users. Leave unspecified to leave this
      #  entity out of user counts. Method signature should accept a single parameter which will specify a date range
      #  If parameter is nil, the total user count should be returned. If the parameter is specified, the number of users
      #  active during the time period should be returned.
      # @param auto_create_actors [Boolean] Whether to automatically create an actor when the entity is created
      # @example
      #   acts_as_federails_actor username_field: :username, name_field: :display_name, profile_url_method: :url_for, actor_type: 'Person'
      # rubocop:disable Metrics/ParameterLists
      def self.acts_as_federails_actor(
        name_field:,
        username_field:,
        profile_url_method: nil,
        actor_type: 'Person',
        user_count_method: nil,
        auto_create_actors: true
      )
        Federails::Configuration.register_entity(
          self,
          username_field:     username_field,
          name_field:         name_field,
          profile_url_method: profile_url_method,
          actor_type:         actor_type,
          user_count_method:  user_count_method,
          auto_create_actors: auto_create_actors
        )
      end
      # rubocop:enable Metrics/ParameterLists

      # Add custom data to actor responses.
      # Override in your own model to add extra data, which will be merged into the actor response
      # generated by Federails. You can include extra `@context` for activitypub extensions and it will
      # be merged with the main response context.
      # @example
      #   def to_activitypub_object
      #     {
      #       "@context": {
      #         toot: "http://joinmastodon.org/ns#",
      #         attributionDomains: {
      #           "@id": "toot:attributionDomains",
      #           "@type": "@id"
      #         }
      #       },
      #       attributionDomains: [
      #         "example.com"
      #       ]
      #     }
      #   end
      def to_activitypub_object
        {}
      end

      private

      def create_actor
        Federails::Actor.create! entity: self
      end
    end
  end
end