// McTrackState.hpp

#ifndef McTrackState_H
#define McTrackState_H

// This class represents the state of a Monte Carlo track at one
// point along its trajectory.  It consists of the path distance and
// a VTrack.

#include <iosfwd>
#include "trfbase/VTrack.h"
#include "gtrbase/DetectorID.hpp"

class McTrackState {

private:

  // The path distance.
  double _s;

  // The track.
  trf::VTrack _trv;

  // The detector element id

  unsigned int _id;
  
public:

  // Default constructor.
  McTrackState();

  // Constructor from s and track.
  McTrackState(double s, const trf::VTrack& trv);
  McTrackState(const McTrackState&);

  // Constructor from s, surface and track vector.
  McTrackState(double s, const trf::SurfacePtr& psrf,
               const trf::TrackVector& vec);

  // Destructor.
  ~McTrackState();

public:

  // Return if this state is valid.
  // This is true if the track is valid.
  bool is_valid() const { return _trv.is_valid(); }

  // Return the path distance.
  double s() const { return _s; }

  // Return the track.
  const trf::VTrack& track() const { return _trv; }

 // Return the id

 DetectorID get_detid() const {return DetectorID(_id);}

 // set id

 void set_detid(const DetectorID& id) {_id=id.get_detector_id();}

};

// Ordering operator.
// Order by s.
bool operator<(const McTrackState& lhs, const McTrackState& rhs);

// Equality operator.
// Require s and track
bool operator==(const McTrackState& lhs, const McTrackState& rhs);

// Output stream.
std::ostream& operator<<(std::ostream& stream, const McTrackState& rhs);

#endif