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

module Contrast
  module Utils
    # ThreadTracker allows tracking of singleton objects across threads
    class ThreadTracker
      def initialize logger = nil
        @logger = logger
      end

      # Note about Ruby -- thread#[] is fiber-local,
      # #thread_variables is not.

      def get key, default = nil
        log(key)
        Thread.current[key] || default
      end

      def set key, value
        Thread.current[key] = value
      end

      def delete key
        Thread.current[key] = nil
      end

      def lifespan obj
        set(:current_context, obj)
        response = yield(obj)
        delete(:current_context)
        response
      end

      def current
        get(:current_context)
      end

      def update_current_context context
        set(:current_context, context)
      end

      # logger may be nil so use this utility method instead
      def log key
        return unless @logger
        return unless @logger.debug?

        @logger.debug('Accessing object in Thread Tracker', name: key, p_id: Process.pid, thread_id: Thread.current.object_id)
      rescue StandardError
        false # NOOP
      end
    end
  end
end