# frozen_string_literal: true

require 'active_support/all'

module Labkit
  module Tracing
    autoload :Common, 'labkit/tracing/common'
    autoload :Factory, 'labkit/tracing/factory'
    autoload :GRPCInterceptor, 'labkit/tracing/grpc_interceptor'
    autoload :JaegerFactory, 'labkit/tracing/jaeger_factory'
    autoload :RackMiddleware, 'labkit/tracing/rack_middleware'

    module Rails
      autoload :ActionViewSubscriber, 'labkit/tracing/rails/action_view_subscriber'
      autoload :ActiveRecordSubscriber, 'labkit/tracing/rails/active_record_subscriber'
      autoload :RailsCommon, 'labkit/tracing/rails/rails_common'
    end

    module Sidekiq
      autoload :ClientMiddleware, 'labkit/tracing/sidekiq/client_middleware'
      autoload :ServerMiddleware, 'labkit/tracing/sidekiq/server_middleware'
      autoload :SidekiqCommon, 'labkit/tracing/sidekiq/sidekiq_common'
    end

    # Only enable tracing when the `GITLAB_TRACING` env var is configured. Note that we avoid using ApplicationSettings since
    # the same environment variable needs to be configured for Workhorse, Gitaly and any other components which
    # emit tracing. Since other components may start before Rails, and may not have access to ApplicationSettings,
    # an env var makes more sense.
    def self.enabled?
      connection_string.present?
    end

    def self.connection_string
      ENV['GITLAB_TRACING']
    end

    def self.tracing_url_template
      ENV['GITLAB_TRACING_URL']
    end

    def self.tracing_url_enabled?
      enabled? && tracing_url_template.present?
    end

    # This will provide a link into the distributed tracing for the current trace,
    # if it has been captured.
    def self.tracing_url(service_name)
      return unless tracing_url_enabled?

      correlation_id = Labkit::Correlation::CorrelationId.current_id.to_s

      # Avoid using `format` since it can throw TypeErrors
      # which we want to avoid on unsanitised env var input
      tracing_url_template.to_s.gsub('{{ correlation_id }}', correlation_id).gsub('{{ service }}', service_name)
    end
  end
end