require 'agent/handler/tracker_handler'

module ManageEngine
  module Instrumentation
    class RailsFramework
      
      def present?
        defined?(::Rails) && defined?(::ActionController)
      end
      
      def version
        Rails::VERSION::STRING
      end
      
      def env
        if Rails::VERSION::MAJOR >= 3 
          ::Rails.env
        else
          RAILS_ENV.dup
        end
      end
      
      def name
        'Rails'
      end
      
      def instrument
        @obj = ManageEngine::APMObjectHolder.instance
        @obj.log.info "Instrumenting ActionController.. Rails Version: #{version}"
        
        ActiveSupport::Notifications.subscribe('start_processing.action_controller') do |name, start, finish, id, payload|
          result = payload[:path].partition("?")
          railsTracker = ManageEngine::Tracker::RootTracker.new("#{payload[:controller]}.#{payload[:action]}", start.to_f * 1000)
          railsTracker.url=(result[0])
          railsTracker.queryString(result[2]) # even if value not available empty string will be returned
          railsTracker.http_method(payload[:method])
          railsTracker.http_params(payload[:params])
            
          railsTracker = ManageEngine::Agent::TrackerHandler.invokeTracker(railsTracker)
          Thread.current[:railsTracker] = railsTracker
        end # subscribe
        
        
        ActiveSupport::Notifications.subscribe('process_action.action_controller') do |name, start, finish, id, payload|
          begin
            railsTracker = Thread.current[:railsTracker]
            if (railsTracker != nil)
              railsTracker.finish(finish.to_f * 1000)
              railsTracker.setStatus(payload[:status])
              exception = payload[:exception_object]
              if exception != nil
                railsTracker.setError(exception)
              end
              ManageEngine::Agent::TrackerHandler.exitTracker(railsTracker)
            end
          rescue Exception=>e
            @obj.log.logException("Unable to process controller event #{name}. Exception: " ,e)
          end
        end
        
      end # def instrument
      
    end
  end
end