# frozen_string_literal: true

# Copyright The OpenTelemetry Authors
#
# SPDX-License-Identifier: Apache-2.0

module OpenTelemetry
  module Instrumentation
    module ActiveJob
      module Patches
        # Module to prepend to ActiveJob::Base for instrumentation.
        module ActiveJobCallbacks
          def self.prepended(base)
            base.class_eval do
              around_enqueue do |job, block|
                span_kind = job.class.queue_adapter_name == 'inline' ? :client : :producer
                span_name = "#{otel_config[:span_naming] == :job_class ? job.class : job.queue_name} send"
                span_attributes = job_attributes(job)
                otel_tracer.in_span(span_name, attributes: span_attributes, kind: span_kind) do
                  OpenTelemetry.propagation.inject(job.metadata)
                  block.call
                end
              end
            end
          end

          def perform_now
            span_kind = self.class.queue_adapter_name == 'inline' ? :server : :consumer
            span_name = "#{otel_config[:span_naming] == :job_class ? self.class : queue_name} process"
            span_attributes = job_attributes(self).merge('messaging.operation' => 'process', 'code.function' => 'perform_now')
            executions_count = (executions || 0) + 1 # because we run before the count is incremented in ActiveJob::Execution

            extracted_context = OpenTelemetry.propagation.extract(metadata)
            OpenTelemetry::Context.with_current(extracted_context) do
              if otel_config[:propagation_style] == :child
                otel_tracer.in_span(span_name, attributes: span_attributes, kind: span_kind) do |span|
                  span.set_attribute('messaging.active_job.executions', executions_count)
                  super
                end
              else
                span_links = []
                if otel_config[:propagation_style] == :link
                  span_context = OpenTelemetry::Trace.current_span(extracted_context).context
                  span_links << OpenTelemetry::Trace::Link.new(span_context) if span_context.valid?
                end

                root_span = otel_tracer.start_root_span(span_name, attributes: span_attributes, links: span_links, kind: span_kind)
                OpenTelemetry::Trace.with_span(root_span) do |span|
                  span.set_attribute('messaging.active_job.executions', executions_count)
                  super
                rescue Exception => e # rubocop:disable Lint/RescueException
                  span.record_exception(e)
                  span.status = OpenTelemetry::Trace::Status.error("Unhandled exception of type: #{e.class}")
                  raise e
                ensure
                  root_span.finish
                end
              end
            end
          ensure
            # We may be in a job system (eg: resque) that forks and kills worker processes often.
            # We don't want to lose spans by not flushing any span processors, so we optionally force it here.
            OpenTelemetry.tracer_provider.force_flush if otel_config[:force_flush]
          end

          private

          def job_attributes(job)
            otel_attributes = {
              'code.namespace' => job.class.name,
              'messaging.destination_kind' => 'queue',
              'messaging.system' => job.class.queue_adapter_name,
              'messaging.destination' => job.queue_name,
              'messaging.message_id' => job.job_id,
              'messaging.active_job.provider_job_id' => job.provider_job_id,
              'messaging.active_job.scheduled_at' => job.scheduled_at,
              'messaging.active_job.priority' => job.priority
            }

            otel_attributes['net.transport'] = 'inproc' if %w[async inline].include?(job.class.queue_adapter_name)

            otel_attributes.compact
          end

          def otel_tracer
            ActiveJob::Instrumentation.instance.tracer
          end

          def otel_config
            ActiveJob::Instrumentation.instance.config
          end
        end
      end
    end
  end
end