///////////////////////////////////////////////////////////////////////
//
// Simple chi squared method
//
// Author: J Amey <jjtamey@googlemail.com>
// Author: Matt Mottram < m.mottram@qmul.ac.uk> -- contact person
//
// REVISION HISTORY:
//     - 08/2012 : J Amey - New file
//     - 10/09/2013 : K Majumdar - Adding in ability to do asymmetric
//        errors and errors in Spherical coordinates
//     - 2014-03-29 : P G Jones - Updated lifetime, added BeginOfRun method
//     - 2014-12-09 : P G Jones - Allow chained PMTSelectors
//     - 2015-02-24 : R Stainforth - Fixed typo in the assignment of
//                                   negative errors
//     - 2015-06-21 : R Stainforth - Add option to seed by SOC object.
//                    Rename class 'SOCPositionTimeChiSquared'
//                    from 'PositionTimeChiSquared'.
//     - 2015-07-09 : R Stainforth - Add bucket time calculation to the
//                                   computation of the time transit.
//     - 2015-09-21 : R Stainforth - Added option to override the value
//                                   of 'fPhotonEnergy' at macro level.
//
// Requires Seeding, optimising and a selector
//
///////////////////////////////////////////////////////////////////////

#ifndef __RAT_Method_SOCPositionTimeChiSquared_
#define __RAT_Method_SOCPositionTimeChiSquared_

#include <string>
#include <stdexcept>

#include <RAT/OptimisedMethod.hh>
#include <RAT/PDFMethod.hh>
#include <RAT/SeededMethod.hh>
#include <RAT/DS/SOC.hh>
#include <RAT/SelectorMethod.hh>
#include <RAT/DU/LightPathCalculator.hh>

namespace RAT
{

namespace DS
{
  class FitResult;
}

namespace Methods
{

  class SOCPositionTimeChiSquared : public SeededMethod, public OptimisedMethod, public SelectorMethod
{
public:
  // Returns the name of the method
  virtual std::string
  GetName() const { return SOCPositionTimeChiSquared::Name(); }
  // Returns the name of the simplechisquared method
  static std::string
  Name() { return std::string( "socPositionTimeChiSquared" ); }
  // Initialises the TruncatedChiSquared method (requires no init string)
  void Initialise( const std::string& ); // Init string, no required

  // Load from the database and setup
  void BeginOfRun( DS::Run& run );

  void EndOfRun( DS::Run& ) { }

  // Set a double paramter
  //
  // param is a parameter name
  // value is the value of the parameter
  void SetD( const std::string& param,
             const double value );

  // Sets the seed to the default
  void DefaultSeed();

  // Seed using a SOC object
  void SeedBySOC( DS::SOC& soc );

  // Invokes the method's algorithm
  virtual DS::FitResult GetBestFit();
  // Called by the optimiser to get the starting/seed params to optimise
  virtual std::vector<double> GetParams() const;
  // Called by the optimiser to get the starting/seed errors to optimise
  virtual std::vector<double> GetPositiveErrors() const;
  virtual std::vector<double> GetNegativeErrors() const;
  // Converts the vector of params into the fFitResult
  virtual void SetParams( const std::vector<double>& params );
  // Converts the vector of errors into the fFitResult
  virtual void SetPositiveErrors( const std::vector<double>& errors );
  virtual void SetNegativeErrors( const std::vector<double>& errors );
  // Called by the optimiser to invoke the method algorithm, optimiser will pass current parameters
  virtual double operator()( const std::vector<double>& params );

protected:
  double fAVRadius; // Radius of the acrylic vessel, method will check fit is within this.
  double fPhotonEnergy; // Assumed energy of the photon when calculating the transit time
  bool fPhotonEnergyOverride; // Boolean flag to determine whether the user has set the wavelength in the macro or if it will be read off of the SOC file by 'SeedBySOC'
  DU::LightPathCalculator fLightPath; // Light path calculator for a given run
};

} //::Methods

} //::RAT

#endif