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

cs__scoped_require 'securerandom'
cs__scoped_require 'set'

cs__scoped_require 'contrast/utils/assess/sampling_util'
cs__scoped_require 'contrast/utils/assess/tracking_util'
cs__scoped_require 'contrast/utils/environment_util'
cs__scoped_require 'contrast/utils/env_configuration_item'
cs__scoped_require 'contrast/utils/gemfile_reader'
cs__scoped_require 'contrast/utils/object_share'
cs__scoped_require 'contrast/utils/performs_logging'
cs__scoped_require 'contrast/utils/string_utils'
cs__scoped_require 'contrast/agent/reaction_processor'
cs__scoped_require 'contrast/agent/require_state'
cs__scoped_require 'contrast/agent/assess/policy/patcher'
cs__scoped_require 'contrast/agent/patching/policy/patcher'
cs__scoped_require 'contrast/components/interface'

module Contrast
  module Agent
    # This class functions as a way to query the Agent for its current
    # configuration without having to expose other sections of code to the
    # decision tree needed to make that determination.
    # It should not be accessed directly, but should instead be inherited from
    #
    # @abstract Use the methods in FeatureState to access this data
    class SettingsState
      include Contrast::Utils::PerformsLogging
      include Contrast::Components::Interface

      INVALID_CONFIG = '!!! CONFIG FILE IS INVALID - DISABLING CONTRAST AGENT !!!'

      access_component :agent, :analysis, :settings, :config, :contrast_service

      MODE_WHITELIST = %i[NO_ACTION BLOCK_AT_PERIMETER MONITOR BLOCK].cs__freeze

      # These are components.
      attr_accessor :last_update,
                    :log_file,
                    :log_level

      # These represent process-level attributes,
      # not directly related to Contrast function itself.
      attr_reader :pid,
                  :ppid

      def initialize
        @instrumentation_mutex = Mutex.new
        @instrumented_packages = {}

        # Last we heard from the Contrast Service
        @last_update = nil

        # keep track of which process instantiated this instance
        @pid  = Process.pid.to_i
        @ppid = Process.ppid.to_i

        init_log_queueing

        check_config

        flush_log_queues
      end

      def check_config
        SETTINGS.reset_state

        if CONFIG.invalid?
          AGENT.disable!
          self.class.log_error(INVALID_CONFIG)
          abort_log_queues
          elseif CONFIG.disabled?
          AGENT.disable!
          self.class.log_warn(LOG_CONFIGURATION_DISABLED)
        else
          AGENT.enable!
        end
      end

      # workaround to mixed use of class/instance
      def self.logger
        instance.logger
      end

      def logger
        logger_manager.current
      end

      def logger_manager
        (@_logger_manager ||= Contrast::Agent::LoggerManager.new.tap(&:update))
      end

      def assess_rule name
        ASSESS.rule name
      end

      def instrument package
        return if @instrumented_packages[package] # double check is intentional

        @instrumentation_mutex.synchronize do
          return if @instrumented_packages[package]

          @instrumented_packages[package] = true
        end

        self.class.debug_with_time("instrumenting #{ package }") do
          cs__scoped_require(package)
        end
      rescue LoadError, StandardError => e
        @instrumented_packages[package] = false
        self.class.log_error("[e.class: #{ e.class }] unable to instrument: #{ package }", e)
      end

      def protect_rule name
        PROTECT.rule name
      end

      def send_inventory_message
        return unless INVENTORY.enabled?

        msg = Contrast::Api::Dtm::ApplicationUpdate.new
        msg.platform = Contrast::Api::Dtm::Platform.new
        msg.platform.major, msg.platform.minor, msg.platform.build = *Contrast::Utils::EnvironmentUtil.platform

        Contrast::Utils::EnvironmentUtil.add_library_to_app_update(msg, protobuf_format(CONFIG.root.inventory.tags))
        Contrast::Utils::EnvironmentUtil.scan_views(msg)
        Contrast::Utils::EnvironmentUtil.scan_routes(msg)
        Contrast::Utils::InventoryUtil.append_db_config(msg)

        CONTRAST_SERVICE.queue_message msg
      end

      def present? str
        Contrast::Utils::EnvironmentUtil.present?(str)
      end

      # CONTRAST-35326, move this responsibility toward the protobuf object
      def protobuf_format param, truncate: true
        param = param&.to_s
        param = Contrast::Utils::StringUtils.force_utf8(param)
        param = Contrast::Utils::StringUtils.truncate(param) if truncate
        param
      end
    end
  end
end