////////////////////////////////////////////////////////////////////////
/// \class RAT::PDFs::CherenkovSourcePDF
///
/// \brief  PDFs for Cherenkov source events
///
/// \author name W. Heintzelman <billh@hep.upenn.edu> -- contact person
///
/// REVISION HISTORY:\n
///     8 July 2013: W. Heintzelman - New file \n
///
/// \details Given a proposed fit vertex (including an event time) and
///         a PMT hit, return the probability of obtaining the
///         observed time residual.
///
////////////////////////////////////////////////////////////////////////

#ifndef __RAT_PDF_CherenkovSourcePDF__
#define __RAT_PDF_CherenkovSourcePDF__

#include <RAT/PDF.hh>
#include <RAT/DU/LightPathCalculator.hh>
#include <string>

class G4PhysicsOrderedFreeVector;

namespace RAT
{

namespace DS {
  class FitVertex;
}

namespace PDFs {
    class CherenkovSourcePDF : public PDF {
        public:
          double GetProbability( const FitterPMT& pmt,
                                         const DS::FitVertex& vertex );

          std::string GetName() const { return Name(); }
          static std::string Name() {return std::string ("CherenkovSourcePDF");}

          /// Initialise the fProbability values vector
          void Initialise( const std::string& param );

          void BeginOfRun( DS::Run& );

          void EndOfRun( DS::Run& ) { }
        protected:
            ///< PDF in a convenient interpolating structure:
            G4PhysicsOrderedFreeVector* fProbability;
        private:
            std::string fIndex; ///< PDF index string
            // Indices of refraction
            double fIdxScint;
            double fIdxAV;
            double fIdxWater;
            DU::LightPathCalculator fLightPath; ///< Light path calculator for a given run
    };

} //::PDFs
} //::RAT
#endif