# Copyright (c) 2022 Contrast Security, Inc. See https://www.contrastsecurity.com/enduser-terms-0317a for more details.
# frozen_string_literal: true

module Contrast
  module Framework
    module Rails
      module Patch
        # This class acts as our patch into the ActionController::Live::Buffer class, allowing us to track the close
        # event on streamed responses.
        module ActionControllerLiveBuffer
          class << self
            # TODO: RUBY-1353
            # TODO: RUBY-1355
            # TODO: RUBY-1357
            # TODO: RUBY-1357
            def send_messages
              return unless (context = Contrast::Agent::REQUEST_TRACKER.current)

              if Contrast::Agent::Reporter.enabled?
                [
                  context.new_observed_route,
                  Contrast::Agent::Reporting::DtmMessage.dtm_to_event(context.server_activity),
                  Contrast::Agent::Reporting::DtmMessage.dtm_to_event(context.activity.library_usages),
                  Contrast::Agent::Reporting::DtmMessage.dtm_to_event(context.activity)
                ].each do |event|
                  Contrast::Agent.reporter&.send_event_immediately(event)
                end
              else
                [context.server_activity, context.activity, context.observed_route].each do |msg|
                  Contrast::Agent.messaging_queue&.send_event_immediately(msg)
                end
              end
            end

            def instrument
              @_instrument ||= begin
                ::ActionController::Live::Buffer.class_eval do
                  # normally pre->in->post filters are applied however, in a streamed response we can run into a case
                  # where it's pre -> in -> post -> more infilters in order to submit anything found during the
                  # infilters after the response has been written we need to explicitly send them
                  alias_method(:cs__close, :close)
                  def close
                    Contrast::Framework::Rails::Patch::ActionControllerLiveBuffer.send_messages
                    cs__close
                  end
                end
                true
              end
            end
          end
        end
      end
    end
  end
end