module Sentry::Rails::Tracing

def self.get_current_transaction
  Sentry.get_current_scope.get_transaction if Sentry.initialized?
end

def self.patch_active_support_notifications
  unless ::ActiveSupport::Notifications::Instrumenter.ancestors.include?(SentryNotificationExtension)
    ::ActiveSupport::Notifications::Instrumenter.send(:prepend, SentryNotificationExtension)
  end
  SentryNotificationExtension.module_eval do
    def instrument(name, payload = {}, &block)
      # only inject timestamp to the events the SDK subscribes to
      if Tracing.subscribed_tracing_events.include?(name)
        payload[START_TIMESTAMP_NAME] = Time.now.utc.to_f if name[0] != "!" && payload.is_a?(Hash)
      end
      super(name, payload, &block)
    end
  end
end

def self.register_subscribers(subscribers)
  @subscribers = subscribers
end

def self.remove_active_support_notifications_patch
  if ::ActiveSupport::Notifications::Instrumenter.ancestors.include?(SentryNotificationExtension)
    SentryNotificationExtension.module_eval do
      def instrument(name, payload = {}, &block)
        super
      end
    end
  end
end

def self.subscribe_tracing_events
  # need to avoid duplicated subscription
  return if @subscribed
  subscribers.each do |subscriber|
    subscriber.subscribe!
    @subscribed_tracing_events ||= []
    @subscribed_tracing_events += subscriber::EVENT_NAMES
  end
  @subscribed = true
end

def self.subscribed_tracing_events
  @subscribed_tracing_events ||= []
end

def self.subscribers
  @subscribers
end

def self.unsubscribe_tracing_events
  return unless @subscribed
  subscribers.each(&:unsubscribe!)
  subscribed_tracing_events.clear
  @subscribed = false
end

def instrument(name, payload = {}, &block)
  # only inject timestamp to the events the SDK subscribes to
  if Tracing.subscribed_tracing_events.include?(name)
    payload[START_TIMESTAMP_NAME] = Time.now.utc.to_f if name[0] != "!" && payload.is_a?(Hash)
  end
  super(name, payload, &block)
end

def instrument(name, payload = {}, &block)
  super
end