////////////////////////////////////////////////////////////////////
/// \class RAT::VertexGen_PrimakoffRosen
///
/// \brief Vertex Generator for double beta decay events.
///
/// \author Jeanne Wilson <j.r.wilson@qmul.ac.uk> -- contact person
///
/// REVISION HISTORY:
///    - first version : 23-July-2008
///    - 2014/06/30 A. Mastbaum - Brought back VertexGen_DoubleBeta after deletion,
///                          renamed to VertexGen_PrimakoffRosen
///    - 2014/11/26 Matt Strait - doxygen fixes
///    - 2015/08/04 Matt Mottram - Use G4IonTable to get ions
///
/// \details This vertex generator (to be used in composite generators like combo or coincidence) produces
/// double beta decay events using isotope information provided in DBD ratdb files.
///
/// The code is based on that produced for the COBRA experiment with formulae derived from
/// Tretyak & Zdesenko, "Tables of Double Beta Decay Data", Atomic Data and Nuclear Data Tables, 61,
/// 43-90 (1995). Calculations use the Primakoff-Rosen approximation for the Fermi function.
///
/// Currently the following methods are available. They are user selected via the mode value.\n
/// 			mode = 0 : 0nuBB 0+0+ transition with 2n mechanism\n
/// 			mode = 2 : 2nuBB 0+0+ transition with 2n mechanism
///
////////////////////////////////////////////////////////////////////

#ifndef __RAT_VertexGen_PrimakoffRosen__
#define __RAT_VertexGen_PrimakoffRosen__

#include <RAT/GLG4VertexGen.hh>
#include "RAT/DB.hh"

#include <G4Event.hh>
#include <G4ThreeVector.hh>
#include <globals.hh>
#include <vector>

namespace RAT {

	class VertexGen_PrimakoffRosen : public GLG4VertexGen {
		public:

		VertexGen_PrimakoffRosen(const char *arg_dbname="DoubleBeta");
		virtual 		~VertexGen_PrimakoffRosen();
		/** generate and add new vertex to this event.  Position and
  		* time of vertex are offset from 0 by dx and dt.  (These
  		* are usually derived from GLG4PosGen and GLG4TimeGen.)
		*/
		virtual void 	GeneratePrimaryVertex( G4Event* argEvent,
						G4ThreeVector& dx,
						G4double dt);
		/** set the state for generator. Format: isotope (mode)
		* where isotope is the parent isotope (Nd150, Nd148),
		* and mode is the decay mode (0= 0nuBB, 2=2nuBB)
		*/
		virtual void 	SetState( G4String newValues );
		/** return current state */
		virtual 		G4String GetState();

		/** calculate the energies for the two betas and the angle between them
		* for the neutrinoless case - 2n mechanism */
		virtual void	ZeroNu2nBasic(G4double& E1, G4double& E2, G4double& btheta);

		/** calculate the energies for the two betas and the angle between them
		* for the two neutrino case - 2n mechanism */
		virtual void	TwoNu2nBasic(G4double& E1, G4double& E2, G4double& btheta);

		/** output energies are only limitable for 2nuBB mode */
		virtual bool 	ELimitable();

		/** Set the limits on the generated energy */
		virtual void	LimitEnergies(float Elo, float Ehi);

		/** Return the maximum possible energy */
		virtual float	EMaximum();

		/** Return the minimum possible energy */
		virtual float	EMinimum();

		private:
		G4ParticleDefinition *fPDef;	// particle definition is used multiple times
		G4String	      fIsotope;	   // parent isotope
		int		      fMode;	      // decay mode
  		DBLinkPtr 	   fLdbdb;	      // database pointer
		float		      fELimUniLow; 	   // user applied universal limits on the generated energy
		float		      fELimUniHigh;
		float		      fELimTempLow;	   // temporary energy limits (apply to one event)
		float		      fELimTempHigh;

	};

} // namespace RAT

#endif