///////////////////////////////////////////////////////////////////////
//
// Fitter Method for NearAV events, using the angular distribution of hit PMTs
//
// Author: Krish Majumdar <Krishanu.Majumdar@physics.ox.ac.uk> -- contact person
//
// REVISION HISTORY:
//     2012-08-21 : K Majumdar - New file
//     2013-01-22 : K Majumdar - removing underscores, tab/space consistency
//     2013-01-29 : K Majumdar - added brief and detail, changed to CamelCase
//     2014-03-29 : P G Jones - Updated lifetime, added BeginOfRun method
//     2014-10-15 : K Majumdar - major changes to update for RAT 5.0 + changed
//                               from pol1 radius vs. ratio fit to pol2
//
// Calculate the event direction by summing over the position vectors
// of hit PMTs, retrieve the ratio of hit PMTs with some angle between
// PMT and event over total hit PMTs (i.e. classifier result), match the
// ratio value against previously coordinated values to find the event
// radius. See document SNO+-doc-1710 for more details on the theta and
// phi errors quantified below.
//
///////////////////////////////////////////////////////////////////////

#ifndef __RAT_Method_NearAVAngular_
#define __RAT_Method_NearAVAngular_

#include <string>

#include <RAT/DS/FitResult.hh>
#include <RAT/Method.hh>

#include <TH1D.h>
using namespace ROOT;

namespace RAT
{
  namespace DS
  {
    class Entry;
    class EV;
  }

  namespace Methods
  {
    class NearAVAngular : public Method
    {

    public:
      // Returns the method's name
      virtual std::string GetName() const {return NearAVAngular::Name();}
      // Returns the method's name
      static std::string Name() {return std::string("nearAVAngular");}
      // Initialise the method
      //
      // param is an optional index in the db to use
      void Initialise(const std::string& param);
      // Load the table from the database
      void BeginOfRun(DS::Run& run);
      void EndOfRun(DS::Run& run);
      // Calculate and return the best fit
      virtual DS::FitResult GetBestFit();
	  // Reposition the hit-times such that the first 3 hits occurring within 1 ns are situated in the 250ns bin
      //
      // histo is a histogram of raw hit-times
      // Returns the centre of the first bin that has a population of more than 3
      double RepositionHistogram(TH1D* histo);

    private:
      std::string fIndex; // Optional index override for the db table
      std::vector<int> fNhitsWindow; // Vector of Nhits window low bounds
      int fWindowWidth; // Nhits window width
      std::vector<double> fFitCoeffs0; // Vector of coefficients for the 0th radius power term in the function that relates radius and ratio value (one for each Nhits window)
      std::vector<double> fFitCoeffs1; // Vector of coefficients for the 1st radius power term in the function that relates radius and ratio value (one for each Nhits window)
      std::vector<double> fFitCoeffs2; // Vector of coefficients for the 2nd radius power term in the function that relates radius and ratio value (one for each Nhits window)
      std::vector<double> fRatioCuts; // Vector of ratio cut values which define the NearAV region (one for each Nhits window)
      std::vector<double> fRatioBins; // Vector of ratio bin low bounds
      double fBinWidth; // Ratio bin width
      std::vector<double> fNegativeErrors; // Vector of errors in the negative radial direction - towards detector centre (one for each Nhits window / ratio bin combination)
      std::vector<double> fPositiveErrors; // Vector of errors in the positive radial direction - towards detector edge (one for each Nhits window / ratio bin combination)
      double fThetaError; // Error in the Reconstructed Theta angle = Sigma of the "theta(true) - theta(reco)" distribution
      double fPhiError; // Error in the Reconstructed Phi angle = Sigma of the "phi(true) - phi(reco)" distribution
      double fAVRadius; // AV radius, taken from geometry file
    };
  }  // End of namespace Methods
}  // End of namespace RAT

#endif