////////////////////////////////////////////////////////////////////
/// \class RAT::GunPMTGamma
///
/// \brief  Generates PMT Gamma events in set filled volume(s).
///
/// \author Sean Grullon <grullons@hep.upenn.edu> -- contact person
///
/// REVISION HISTORY:\n
///     10 Sep 2013 : Sean Grullon  - Initial definition
///     16 Aug 2020 : Juan Pablo Yanez - Added the missing beta
///
///  \details
/// An extra GLG4Vertex generator class for primary events,
///  based on Bill Heintzelman's weighted PMT gamma
// distribution  (See docdb 1712) for details about
// the weighting) This generator takes the generated R position,
///and samples from Bill's weighting function to get the
// appropriate angular distribution for PMT gammas.
// Note, this generator is only physically meaningful for
// PMT 2.6 MeV gammas, and not for other backgrounds or particles
// It now also has the accompanying beta to go with the gamma
////////////////////////////////////////////////////////////////////
#ifndef __GunPMTGamma_h__
#define __GunPMTGamma_h__


#include <RAT/GLG4VertexGen.hh>

class GLG4VertexGen_GunPMTGamma : public GLG4VertexGen {
public:
  // only generate primary vertex is overloaded...
  GLG4VertexGen_GunPMTGamma(const char *arg_dbname="gunpmtgamma");
  virtual ~GLG4VertexGen_GunPMTGamma();

  virtual void GeneratePrimaryVertex( G4Event *argEvent,
				      G4ThreeVector &dx,
				      G4double dt);

  virtual void SetState( G4String newValues );
  // format: gamma_kinetic_energy beta_radius beta_energy_scale
  // particle is hardcoded to be a gamma.

  virtual G4String GetState();
  // returns current state formatted as above
  // the following useful static const data should be universally accessible
  // (I copied it from the G4IonTable source code, where it is privatized
  // with no accessor functions.)


protected:
  G4ParticleDefinition *fPDef;
  G4ParticleDefinition *fPDefBeta;
  G4double fKe;
  G4double fBetaRadius;
  G4double fBetaEscale;

};

#endif