# Copyright (c) 2015 Sqreen. All Rights Reserved.
# Please refer to our terms for more information: https://www.sqreen.io/terms.html

require 'sqreen/performance_notifications'

module Sqreen
  module PerformanceNotifications
    # Log performances on the console
    class NewRelic
      @subid = nil
      @level = 0

      class << self
        def timings
          v = SharedStorage.get(:log_performance_nr_timings)
          if v.nil?
            v = []
            self.timings = v
          end
          v
        end

        def timings=(value)
          SharedStorage.set(:log_performance_nr_timings, value)
        end

        def log(event, start, finish, _meta)
          timings << [event, start, finish]
        end

        def enabled?
          !@subid.nil?
        end

        def report(hash)
          if ::NewRelic::Agent.respond_to?(:add_custom_attributes)
            return ::NewRelic::Agent.add_custom_attributes(hash)
          end
          ::NewRelic::Agent.add_custom_parameters(:user_id => @user.id)
        end

        def next_request
          return unless enabled?
          if @level == 1
            overhead = timings.map do |_evt, start, finish|
              (finish - start) * 1000
            end.inject(0, &:+)
            report('sqreen_time' => overhead)
          else
            output = timings.map do |evt, start, finish|
              [evt.split('/')[1], (finish - start) * 1000]
            end
            total = 0
            count = 0
            rules = output.inject({}) do |acc, (e, t)|
              tt, cc = (acc[e] || [0, 0])
              acc[e] = [tt + t, cc + 1]
              total += t
              count += 1
              acc
            end
            attrs = rules.inject('sqreen_time' => total, 'sqreen_count' => count) do |acc, (rule, values)|
              acc["sqreen_#{rule}_time"] = values[0]
              acc["sqreen_#{rule}_count"] = values[1]
              acc
            end
            report(attrs)
          end
          self.timings = []
        end

        def enable(level = 0)
          return unless @subid.nil?
          return unless defined?(::NewRelic::Agent)
          return unless ::NewRelic::Agent.respond_to?(:add_custom_attributes) || ::NewRelic::Agent.respond_to?(:add_custom_parameters)
          return unless level > 0
          @level = level
          Sqreen.log.debug('Enabling New Relic reporting')
          @subid = Sqreen::PerformanceNotifications.subscribe(&method(:log))
        end

        def disable
          return if @subid.nil?
          Sqreen::PerformanceNotifications.unsubscribe(@subid)
          @subid = nil
          @level = 0
        end
      end
    end
  end
end