#ifndef __MUTKALMANTRACKHIT_H__
#define __MUTKALMANTRACKHIT_H__
// MutKalmanTrackHit.h 
//
// Kalman track hit for muon tracker: header file
//---------------------------------------------------------------------

#include "TObject.h"

#include "MutKalmanTrack.h" // object belongs to the class
#include "MutKalmanTrackParam.h" // object belongs to the class

class TVectorD;
class TMatrixD;

// "public TObject" to use Root facilities
class MutKalmanTrackHit : public TObject {

 public:
  MutKalmanTrackHit(Int_t NMeas = 1); // constructor with "NMeas" measurements (default: 1) 
  virtual ~MutKalmanTrackHit(); // destructor
  MutKalmanTrackHit (const MutKalmanTrackHit& TrackHit); // copy constructor
  MutKalmanTrackHit& operator=(const MutKalmanTrackHit& TrackHit); // assignment operator

  MutKalmanTrack* GetTrack() {return fTrack;}
  void SetTrack(MutKalmanTrack* Track) {fTrack = Track;}
  Double_t GetZ() {return fZ;}
  void SetZ(Double_t Z) {fZ = Z;}
  Int_t GetNMeas() {return fNMeas;}
  TVectorD* GetMeas() {return fMeas;}
  void SetMeas1(Double_t Meas0);
  void SetMeas1Z(Double_t Meas0, Double_t Z);
  void SetMeas2(Double_t Meas0, Double_t Meas1);
  void SetMeas2Z(Double_t Meas0, Double_t Meas1, Double_t Z);
  TMatrixD* GetCovMeas() {return fCovMeas;}
  void SetCovMeas(TMatrixD* CovMeas);
  TMatrixD* GetDMeasDXY() {return fDMeasDXY;}
  void SetDMeasDXY(TMatrixD* DMeasDXY);
  TMatrixD* GetPropagatorParDeriv() {return fPropagatorParDeriv;}
  MutKalmanTrackParam* GetTrackParam(Int_t PredFiltSmooth) {return &fTrackParam[PredFiltSmooth];} // Predicted(0)-Filtered(1)-Smoothed(2)
  void SetTrackParam(Int_t PredFiltSmooth, MutKalmanTrackParam* Param) {fTrackParam[PredFiltSmooth] = *Param;}
  TVectorD* GetTrueParam() {return fTrueParam;}
  void SetTrueParam(Double_t X, Double_t Y,
		    Double_t Px, Double_t Py, Double_t Pz);
  Double_t GetChi2M() {return fChi2M;}
  void SetChi2M(TMatrixD* Chi2M);
  Double_t GetChi2P() {return fChi2P;}
  void SetChi2P(TMatrixD* Chi2P);

  MutKalmanTrackHit* Next() {return (MutKalmanTrackHit*) (fTrack->GetTrackHitsPtr()->After((MutKalmanTrackHit*) (this)));}
  MutKalmanTrackHit* Prev() {return (MutKalmanTrackHit*) (fTrack->GetTrackHitsPtr()->Before((MutKalmanTrackHit*) (this)));}

/*   void FillWithHitFromDMuoTracksClass(dMuoTracksClass* MuoTrack, Int_t stNumber, Int_t stHitNumber); */

  void Print();

 protected:

 private:
  MutKalmanTrack *fTrack; //! Pointer to the track the hit belongs to
  // information about raw hit
  Double_t fZ; //! Z position in cm
  Int_t fNMeas; //! number of measurements
  TVectorD *fMeas; //! pointer to: measurements in cm (not necessarily X and Y)
  TMatrixD *fCovMeas; //! pointer to: covariance matrix of measurements in cm**2
  TMatrixD *fDMeasDXY; //! pointer to: matrix of derivatives of measurements with respect to X and Y
  TMatrixD *fPropagatorParDeriv; //! Track propagator: partial derivatives of track parameters
/*   TMatrixD *fPropagatorCovMatrix; //! Track propagator: covariance matrix of track parameters */
  MutKalmanTrackParam fTrackParam[3]; //! Track parameters: predicted (0), filtered (1) and smoothed (2)
  TVectorD *fTrueParam; //! True track parameters if simulated track
  Double_t fChi2M; //! chi squared from measurement
  Double_t fChi2P; //! chi squared from propagation

  // class version
  ClassDef(MutKalmanTrackHit, 1) // Kalman track in PHENIX dimuon spectrometer
    };
#endif /*__MUTKALMANTRACKHIT_H__*/