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


/** CbmMCTrack.h
 *@author V.Friese <v.friese@gsi.de>
 **
 ** Data class for storing Monte Carlo tracks processed by the CbmStack.
 ** 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 CBMMCTRACK_H
#define CBMMCTRACK_H 1


#include "CbmDetectorList.h"

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

#include <string>

class TParticle;

using std::string;

class CbmMCTrack : public TObject
{

 public:


  /**  Default constructor  **/
  CbmMCTrack();


  /**  Standard constructor  **/
  CbmMCTrack(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  **/
  CbmMCTrack(const CbmMCTrack& track);


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


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

  Int_t AccMVD() const {return GetNPoints(kMVD);}
  Int_t AccSTS() const {return GetNPoints(kSTS);}
  Int_t AccPSD() const {return GetNPoints(kPSD);}

  /**  Accessors  **/
  UInt_t   GetGeantProcessId()  const { return fProcessId; }
  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 GetCharge()   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) const; 
  void Get4Momentum(TLorentzVector& momentum) const;
  void GetStartVertex(TVector3& vertex) const;


  /** 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);


  /** String output **/
  string ToString() const;


private:

  /**  TMCProcess code  **/
  UInt_t  fProcessId;

  /**  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;

  /** energy at start vertex [GeV]  **/
  Double32_t fE;

  /** 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(CbmMCTrack,3)

};



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

inline Double_t CbmMCTrack::GetEnergy() const {
  if(fE>0.) return fE;
  Double_t mass = GetMass();
  return TMath::Sqrt(mass*mass + fPx*fPx + fPy*fPy + fPz*fPz );
}


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


inline void CbmMCTrack::Get4Momentum(TLorentzVector& momentum) const {
  momentum.SetXYZT(fPx,fPy,fPz,GetEnergy()); 
}


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





#endif