////////////////////////////////////////////////////////////////////////
///
/// \class  MultiPDF
///
/// \brief  Fitter method for using different PDFs for different PMT
///         or PDF position
///
/// \author Will Parker     william.parker@physics.ox.ac.uk
///
/// REVISION HISTORY:
/// Oct 22, 2020 :  Will Parker   First revision, new file.
///
/// Mar 17, 2021 :  Will Parker   Generalising method so not so specific
///                               to partial fill case. Now initialise
///                               with string to determine whether to use
///                               full fill or partial (this determines
///                               which db tables to use, and which set of pdfs).
///                               For using position dependent pdfs, instead of
///                               "position relative to fill level center" we now
///                               have a "position relative to origin". In partial
///                               fill the "origin" is set as center of fill level
///                               as pdfs are split by distance relative to fill
///                               level. For full fill the origin is set as center
///                               of AV. But you could set the 'origin' as any
///                               point and use the distance from that to split
///                               pdfs.
///
/// Jan 16, 2024 :  Will Parker   Use seed result to determine which radial shell
///                               to select PDF for. PDF now gets chosen once per
///                               event instead of per fit iteration
///
/// \detail Method uses different pdfs to fit vertex position. The
///         different pdfs correspond to different regions of the av,
///         and different pmt heights. If the seed position is within
///         50 cm of the boundary separating the position-dependent
///         pdfs, then non-vertex-position dependent pdfs are used
////////////////////////////////////////////////////////////////////////

#ifndef __RAT_MultiPDF__
#define __RAT_MultiPDF__

#include <RAT/OptimisedMethod.hh>
#include <RAT/PDFMethod.hh>
#include <RAT/SeededMethod.hh>
#include <RAT/SelectorMethod.hh>
#include <RAT/Processor.hh>
#include <RAT/FitterPMT.hh>
#include "TVectorD.h"

namespace RAT {

namespace Methods {

  class MultiPDF :  public SeededMethod, SelectorMethod
{
public:

  /// Returns the name
  virtual std::string GetName() const { return MultiPDF::Name(); }

  /// Fitter structure name
  static std::string Name() { return std::string("multipdf"); }

  /// Constructor
  MultiPDF();

  /// Destructor
  ~MultiPDF();

  /// Initialise the method
  void Initialise( const std::string& );

  /// Set the default seed (origin, t=230ns, big errors)
  virtual void DefaultSeed();

  /// Reads constants from the database
  /// FIT_MULTIPDF.ratdb
  virtual void BeginOfRun( DS::Run& run );

  /// Forwards EndOfRun to VertexFunction
  virtual void EndOfRun( DS::Run& run );

  /// Runs the algorithm and returns the answer
  virtual DS::FitResult GetBestFit();

  // Default fitters may have subroutines that set the same FOM name for different parameters
  // Add a prefix for the FOM name in the final result to distinguish them.
  void SetFOMs( DS::FitResult& fitResult, const DS::FitResult& MultiPDF, const std::string& prefix );

protected:

  Methods::Method* fPositionTime;
  Methods::Method* fPositionTimeNonPosDep;
  Optimisers::Optimiser* fPowell;
  PMTSelectors::PMTSelector* fNullSelector;
  PDFs::PDF* fMultiPDFs;
  PDFs::PDF* fMultiPDFsNonPosDep;

  std::string fGeo; // Full scintillator fill ("scint") or partial fill ("scintwater")
  int fNumPosDepPDFs; // Number of position dependent pdfs
  int fNumNonPosDepPDFs; // Number of non-position depdendent pdfs
  double fFillLevel;
  std::vector <double> fAV_offset;
  TVector3 fFillLevelCentre; // For determining if seed result is in different region to final result
  TVector3 fOrigin; // For determining if seed result is in different region to final result. This is the center of the fill Level for partial fill, center of AV for full fill
  std::vector <double> fRBoundary; // For determining if seed result is close to boundary between position depedent pdfs
  int fBoundaryRange; // If seed result within this range of position boundary, use non-position-dependent PDFs. Units: mm
};

} //::Methods

} //::RAT

#endif