# Copyright (c) 2020 Contrast Security, Inc. See https://www.contrastsecurity.com/enduser-terms-0317a for more details.
# frozen_string_literal: true

require 'contrast/components/interface'

module Contrast
  module Extension
    module Assess
      # This is our patch of the Array class required to handle propagation
      # Disclaimer: there may be a better way, but we're in a 'get it work' state.
      # Hopefully, we'll be in a 'get it right' state soon.
      # This module is used for our Marshal#load patches
      class MarshalPropagator
        include Contrast::Components::Interface

        access_component :logging

        class << self
          def cs__load_trigger_check source, ret
            current_context = Contrast::Agent::REQUEST_TRACKER.current
            return unless current_context

            # Since we know this is the source of the trigger, we can do some
            # optimization here and return when it is not tracked
            return unless Contrast::Agent::Assess::Tracker.tracked?(source)

            args = [source]
            # source might not be all the args passed in, but it is the one we care
            # about. we could pass in all the args in the last param here if it
            # becomes an issue in rendering on TS
            Contrast::Agent::Assess::Policy::TriggerMethod.build_finding(
                current_context,
                trigger_node('Marshal', :load),
                source,
                self,
                ret,
                args)
            properties = Contrast::Agent::Assess::Tracker.properties(ret)
            properties.copy_from(source, ret)

            node = Contrast::Agent::Assess::Policy::Policy.instance.find_propagator_node('Marshal', :load, false)
            properties.build_event(node, ret, self, ret, args)
          rescue StandardError => e
            logger.error('Unable to determine if a trigger occurred in Marshal.load', e)
          end

          def instrument_marshal_load
            @_instrument_marshal_load ||= begin
              require 'cs__assess_marshal_module/cs__assess_marshal_module'
              true
            end
          rescue StandardError, LoadError => e
            logger.error('Error loading marshal load patch', e)
            false
          end

          def trigger_node clazz, method
            triggers = Contrast::Agent::Assess::Policy::Policy.instance.triggers
            return unless triggers

            triggers.find { |node| node.class_name == clazz && node.method_name == method }
          end
        end
      end
    end
  end
end