# frozen_string_literal: true

require 'active_job'
require 'toot'
require 'wcc/auth'
require 'wcc/data'

class WCC::Media::Engine < ::Rails::Engine
  isolate_namespace WCC::Media

  class << self
    def subscribe(channel, handler = nil, &block)
      handler ||= Proc.new(&block)
      with_toot_config do |c|
        c.subscribe :media, channel, handler
      end
    end

    def initialized
      # Don't register subscriptions unless
      # 1. we mounted the engine and
      # 2. something subscribed.
      ::Toot.config.callback_url &&
        ::Toot.config.subscriptions.any? { |s| s.source.name == :media }
    end

    def register_subscriptions
      return unless initialized

      raise StandardError, "WCC::Auth must be configured" unless WCC::Auth.config.app_name.present? && WCC::Auth.config.app_url.present?

      RegistersSubscriptionsJob.perform_later
    end

    # Ensures toot is configured properly with the Media channel.  Note this is
    # not done until an actual subscription is requested.
    def with_toot_config(&block)
      return ::Toot.config(&block) if @configured

      ::Toot.config do |c|
        media_api_url = WCC::Media::Client.default.api_url

        c.source :media,
          channel_prefix: "org.watermark.media.",
          subscription_url: URI.join(media_api_url, '/toot/subscriptions')

        # Note - use the [] method to override only if not set in client already
        c[:http_connection] ||=
          Faraday::Connection.new do |conn|
            conn.use :client_app_token
            conn.adapter :net_http
          end

        yield c
      end
      @configured = true
    end
  end

  initializer 'configure WCC::Media Toots' do
    ActiveSupport::Notifications.subscribe 'routes_loaded.engine.media.wcc' do
      ::Toot.config.callback_url ||= Rails.application.routes.url_helpers.wcc_media_url +
        '/callbacks'

      WCC::Media::Engine.register_subscriptions
    end
  end

  config.generators do |g|
    g.test_framework :rspec, fixture: false
  end

  class RegistersSubscriptionsJob < ::ActiveJob::Base
    self.queue_adapter = :async

    def perform
      Toot::RegistersSubscriptions.call
    rescue WCC::Data::Mapper::ServiceUnavailable => e
      _handle_error(e)
    rescue Faraday::ConnectionFailed => e
      _handle_error(e)
    rescue Faraday::TimeoutError => e
      _handle_error(e)
    rescue Toot::RegisterSubscriptionFailure => e
      raise unless e.status == 503

      _handle_error(e)
    end

    private

    def _handle_error(err)
      logger.error "Server is down (will not retry): #{err.class} #{err}"
    end
  end
end