// -------------------------------------------------------------------------
// -----                TpcRootGiBUUGenerator header file             -----
// -----          Created 03/04/12  by S. Doerheim                     -----
// -------------------------------------------------------------------------

/**  TpcRootGiBUUGenerator.h
 *@author V.Friese    <v.friese@gsi.de>
 *@author D.Bertini   <d.bertini@gsi.de>
 *@author M.Al-Turany <M.Al-Turany@gsi.de>
 *@author S. Dorheim  <sverre.dorheim@tum.de>

 The TpcRootGiBUUGenerator is adapted from the FairAsciiGenerator to read
 ascii files generated from the GiBUU event generator.
 The format of the files are as follows:
 NTRACKS UNUSED WEIGHT UNUSED UNUSED UNUSED
 PDGCODE PX     PY     PZ     E      Mass
 Momentum in GeV/c, Mass GeV/c^2, Energy in GeV

 Derived from FairGenerator.
**/


#ifndef TPC_GIBUU_ROOTGENERATOR_H
#define TPC_GIBUU_ROOTGENERATOR_H


#include "FairGenerator.h"

#include <fstream>

#include <TFile.h>
#include <TTree.h>
class TDatabasePDG;
class FairPrimaryGenerator;
class TVector3;


class TpcRootGiBUUGenerator : public FairGenerator
{

  public:

    /** Default constructor without arguments should not be used. **/
    TpcRootGiBUUGenerator();


    /** Standard constructor.
     ** @param fileName The input file name
     **/
    TpcRootGiBUUGenerator(const char* fileName);

    /** Sets line in file to start reading events
     ** @param eventNbr
     **/
    bool SetStartEvent(unsigned int eventNbr);

    /** Destructor. **/
    virtual ~TpcRootGiBUUGenerator();

    /**Only write events which contain a particle
     **with type pdgID
     **/
    void ParticleFilter(int pdgID){
      filter_on_PDG=true;
      pdgToFilter=pdgID;
    }

    /** Reads on event from the input file and pushes the tracks onto
     ** the stack. Abstract method in base class.
     ** @param primGen  pointer to the FairPrimaryGenerator
     **/
    virtual Bool_t ReadEvent(FairPrimaryGenerator* primGen);
    void SetTargetThickness(double thickness){
      targetThickness=thickness;
    }
    void SetVetoRadius(double radius){
      vetoR=radius;
    }


  private:


    TFile* fInputFile;               //! Input file stream
    TTree* fInputTree;
    const Char_t* fFileName;            //! Input file Name
    double vetoR; //assumes circular veto detector, alowing for a hole of radius R around the z-axis
    double targetThickness;
    bool filter_on_PDG;
    int pdgToFilter;
    /** Private method CloseInput. Just for convenience. Closes the
     ** input file properly. Called from destructor and from ReadEvent. **/
    void CloseInput();
    int evNb;         //general EvNb (used for event filtering)
    int evNbFile;     //line number in tree
    int realEvNbFile; //Actual eventnumber
    TpcRootGiBUUGenerator(const TpcRootGiBUUGenerator&);
    TpcRootGiBUUGenerator& operator=(const TpcRootGiBUUGenerator&);
    void GenerateVertex(double& vx,double& vy,double& vz);
    Bool_t ReadFileEvent(std::vector<TVector3> &mom,
                         std::vector<int> &pdgs,
                         std::vector<double> &energies,
                         Bool_t &found);
    /** PDG data base */

    float Evt, Mul, Pid, Px, Py, Pz, E, M;
    TDatabasePDG *fPDG; //!

    ClassDef(TpcRootGiBUUGenerator,1);

};

#endif