// ----- FairM
// -------------------------------------------------------------------------
// -----                      FairMCTrack header file                   -----
// -----                  Created 03/08/04  by V. Friese               -----
// -------------------------------------------------------------------------


/** FairMCTrack.h
 *@author V.Friese <v.friese@gsi.de>
 **
 ** Data class for storing Monte Carlo tracks processed by the FairStack.
 ** A MCTrack can be a primary track put into the simulation or a
 ** secondary one produced by the transport through decay or interaction.
 **
 ** Redesign 13/06/07 by V. Friese
 **/


#ifndef FAIRMCTRACK_H
#define FAIRMCTRACK_H 1


#include "FairDetectorList.h"

#include "TLorentzVector.h"
#include "TObject.h"
#include "TParticle.h"
#include "TVector3.h"

#ifndef ROOT_TParticlePDG
#include "TParticlePDG.h"
#endif
#ifndef ROOT_TDatabasePDG
#include "TDatabasePDG.h"
#endif


class FairMCTrack : public TObject
{

  public:


    /**  Default constructor  **/
    FairMCTrack();


    /**  Standard constructor  **/
    FairMCTrack(Int_t pdgCode, Int_t motherID, Double_t px, Double_t py,
                Double_t pz, Double_t x, Double_t y, Double_t z,
                Double_t t, Int_t nPoints);

    /**  Copy constructor  **/
    FairMCTrack(const FairMCTrack& track);


    /**  Constructor from TParticle  **/
    FairMCTrack(TParticle* particle);


    /**  Destructor  **/
    virtual ~FairMCTrack();


    /**  Output to screen  **/
    void Print(Int_t iTrack=0) const;


    /**  Accessors  **/
    Int_t    GetPdgCode()  const { return fPdgCode; }
    Int_t    GetMotherId() const { return fMotherId; }
    Double_t GetPx()       const { return fPx; }
    Double_t GetPy()       const { return fPy; }
    Double_t GetPz()       const { return fPz; }
    Double_t GetStartX()   const { return fStartX; }
    Double_t GetStartY()   const { return fStartY; }
    Double_t GetStartZ()   const { return fStartZ; }
    Double_t GetStartT()   const { return fStartT; }
    Double_t GetMass()     const;
    Double_t GetEnergy()   const;
    Double_t GetPt()       const { return TMath::Sqrt(fPx*fPx+fPy*fPy); }
    Double_t GetP() const { return TMath::Sqrt(fPx*fPx+fPy*fPy+fPz*fPz); }
    Double_t GetRapidity() const;
    void GetMomentum(TVector3& momentum);
    void Get4Momentum(TLorentzVector& momentum);
    void GetStartVertex(TVector3& vertex);


    /** Accessors to the number of MCPoints in the detectors **/
    Int_t GetNPoints(DetectorId detId)  const;


    /**  Modifiers  **/
    void SetMotherId(Int_t id) { fMotherId = id; }
    void SetNPoints(Int_t iDet, Int_t np);



  private:

    /**  PDG particle code  **/
    Int_t  fPdgCode;

    /**  Index of mother track. -1 for primary particles.  **/
    Int_t  fMotherId;

    /** Momentum components at start vertex [GeV]  **/
    Double32_t fPx, fPy, fPz;

    /** Coordinates of start vertex [cm, ns]  **/
    Double32_t fStartX, fStartY, fStartZ, fStartT;

    /**  Bitvector representing the number of MCPoints for this track in
     **  each subdetector. The detectors are represented by
     **  REF:         Bit  0      (1 bit,  max. value  1)
     **  MVD:         Bit  1 -  3 (3 bits, max. value  7)
     **  STS:         Bit  4 -  8 (5 bits, max. value 31)
     **  RICH:        Bit  9      (1 bit,  max. value  1)
     **  MUCH:        Bit 10 - 14 (5 bits, max. value 31)
     **  TRD:         Bit 15 - 19 (5 bits, max. value 31)
     **  TOF:         Bit 20 - 23 (4 bits, max. value 15)
     **  ECAL:        Bit 24      (1 bit,  max. value  1)
     **  ZDC:         Bit 25      (1 bit,  max. value  1)
     **  The respective point numbers can be accessed and modified
     **  with the inline functions.
     **  Bits 26-31 are spare for potential additional detectors.
     **/
    Int_t fNPoints;


    ClassDef(FairMCTrack,2);

};



// ==========   Inline functions   ========================================

inline Double_t FairMCTrack::GetEnergy() const
{
  Double_t mass = GetMass();
  return TMath::Sqrt(mass*mass + fPx*fPx + fPy*fPy + fPz*fPz );
}


inline void FairMCTrack::GetMomentum(TVector3& momentum)
{
  momentum.SetXYZ(fPx,fPy,fPz);
}


inline void FairMCTrack::Get4Momentum(TLorentzVector& momentum)

{
  momentum.SetXYZT(fPx,fPy,fPz,GetEnergy());
}


inline void FairMCTrack::GetStartVertex(TVector3& vertex)
{
  vertex.SetXYZ(fStartX,fStartY,fStartZ);
}





#endif