#ifndef __JDAQEVALUATOR__
#define __JDAQEVALUATOR__

#include "km3net-dataformat/online/JDAQUTCExtended.hh"
#include "km3net-dataformat/online/JDAQHeader.hh"
#include "km3net-dataformat/online/JDAQEvent.hh"


/**
 * \author mdejong
 */

namespace KM3NETDAQ {

  /**
   * Auxiliary class to determine value of DAQ objects.
   */
  struct JDAQEvaluator {
    /**
     * Default constructor.
     */
    JDAQEvaluator()
    {}


    /**
     * Get value of object.
     *
     * \param  object          UTC time
     * \return                 value
     */
    inline double operator()(const JDAQUTCExtended& object) const
    {
      return getTimeDifference(getUTC(), object) * 1.0e-9;
    }


    /**
     * Get value of object.
     *
     * \param  object          event
     * \return                 value
     */
    inline double operator()(const JDAQHeader& object) const
    {
      return(*this)(object.getTimesliceStart());
    }


    /**
     * Get value of event.
     *
     * \param  object          event
     * \return                 value
     */
    inline double operator()(const JDAQEvent& object) const
    {
      return getTimeDifference(getUTC(), object.getTimesliceStart()) * 1.0e-9  +  object.getCounter() * getWeight();
    }


    /**
     * Get relative weight for JDAQEvent evaluation.
     *
     * This value should be less than the ratio of
     * the expected maximum number of events in a single data taking run and
     * the frame duration in units of nano seconds.
     *
     * \return                 weigth [ns]
     */
    static double getWeight()
    {
      return 1.0e-6; // [ns]
    }


    /**
     * Get arbitrary offset.
     *
     * \return                 UTC time
     */
    static const JDAQUTCExtended& getUTC() 
    {
      static JDAQUTCExtended utc(1600000000, 0);

      return utc;
    }
  };


  /**
   * Function object for evaluation of DAQ objects.
   */
  static const JDAQEvaluator getDAQValue;
}

#endif