#include <string>
#include <iostream>
#include <fstream>
#include <iomanip>
#include <vector>
#include <map>

#include "TROOT.h"
#include "TFile.h"
#include "TH1D.h"
#include "TProfile.h"
#include "TRandom3.h"

#include "JTools/JFunction1D_t.hh"
#include "JTools/JFunctionalMap_t.hh"
#include "JTools/JAbstractHistogram.hh"
#include "JPhysics/JCDFTable.hh"
#include "JPhysics/JPDFTypes.hh"
#include "JPhysics/JPDFToolkit.hh"
#include "JGeometry3D/JAngle3D.hh"
#include "JROOT/JRootToolkit.hh"
#include "JROOT/JManager.hh"
#include "Jeep/JTimer.hh"
#include "Jeep/JParser.hh"
#include "Jeep/JMessage.hh"


/**
 * \file
 *
 * Program to verify generation of arrival times of Cherenkov photons from a muon using tabulated CDF.
 * \author mdejong
 */
int main(int argc, char **argv)
{
  using namespace std;
  using namespace JPP;

  typedef JAbstractHistogram<double> JHistogram_t;

  vector<string> inputFile;
  string         outputFile;
  double         E;
  double         R;
  JAngle3D       dir;
  int            numberOfEvents;
  JHistogram_t   histogram;
  int            debug;

  try { 

    JParser<> zap("Program to verify generation of arrival times of Cherenkov photons from a muon using tabulated CDF.");

    zap['f'] = make_field(inputFile);
    zap['o'] = make_field(outputFile)                              = "";
    zap['E'] = make_field(E,         "muon energy [GeV]")          = 1.0;
    zap['R'] = make_field(R,         "distance of approach [m]");
    zap['D'] = make_field(dir,       "(theta, phi) of PMT [rad]");
    zap['n'] = make_field(numberOfEvents)                          = 0;
    zap['H'] = make_field(histogram, "histogram binning")          = JHistogram_t();
    zap['d'] = make_field(debug)                                   = 2;

    zap(argc, argv);
  }
  catch(const exception& error) {
    FATAL(error.what() << endl);
  }


  typedef JHermiteSplineFunction1D_t                              JFunction1D_t;
  //typedef JSplineFunction1D_t                                     JFunction1D_t;
  //typedef JPolint1Function1D_t                                    JFunction1D_t;
  typedef JMAPLIST<JPolint1FunctionalMap,
		   JPolint1FunctionalGridMap,
		   JPolint1FunctionalGridMap>::maplist            JMapList_t;
  typedef JCDFTable<JFunction1D_t, JMapList_t>                    JCDF_t;

  const int N = inputFile.size();

  int    type[N];
  JCDF_t cdf [N];

  try {

    for (int i = 0; i != N; ++i) {

      NOTICE("loading input from file " << inputFile[i] << "... " << flush);

      type[i] = getPDFType(inputFile[i]);

      cdf [i].load(inputFile[i].c_str());

      NOTICE("OK" << endl);
    }
  }
  catch(const JException& error) {
    FATAL(error.what() << endl);
  }


  if (outputFile == "") {

    for ( ; ; ) {

      double  x;

      cout << "> " << flush;
      cin  >> x;

      cout << " --> ";

      for (int i = 0; i != N; ++i) {
      
	try {
        
	  double npe = cdf[i].getNPE (R, dir.getTheta(), dir.getPhi());
	  double t   = cdf[i].getTime(R, dir.getTheta(), dir.getPhi(), x);

	  if        (is_bremsstrahlung(type[i])) {
	    npe *= E;
	  } else if (is_deltarays(type[i])) {
	    npe *= getDeltaRaysFromMuon(E);
	  }

	  cout << ' ' << FIXED(6,2) << t << ' ' << FIXED(5,2) << npe;
	}
	catch(const exception& error) {
	  ERROR(error.what() << endl);
	}
      }

      cout << endl;
    }

    return 0;
  }
   

  int function = 0;

  if (inputFile.size() == 1 && getPDFType(inputFile[0]) == DIRECT_LIGHT_FROM_MUON) {
    function = 1;
  }

  //const double z0   = -100.0;                                 // [m]
  //const double t0   = (-z0 +  R * getTanThetaC()) / C;        // time [ns]
  const double t0   =  0.0;                                   // time [ns]

  if (!histogram.is_valid()) {

    if (function == 1) {

      histogram = JHistogram_t(t0 - 20.0, t0 + 50.0);

      histogram.setBinWidth(0.5);

    } else {

      histogram = JHistogram_t(t0 - 20.0, t0 + 500.0);

      histogram.setBinWidth(2.0);
    }
  }

  TH1D h0("h0", NULL, histogram.getNumberOfBins(), histogram.getLowerLimit(), histogram.getUpperLimit());

  h0.Sumw2();
  
  JManager<int, TH1D> H1(new TH1D("h1[%]", NULL, 100000, 0.0, +1.0));
  
  for (int i = 0; i != N; ++i) {
    
    for (int j = 1; j <= H1->GetNbinsX(); ++j) {
    
      try {
      
	const double x = H1->GetBinCenter(j);
	const double t = cdf[i].getTime(R, dir.getTheta(), dir.getPhi(), x);
      
	H1[i]->SetBinContent(j, t);
      }
      catch(const exception& error) {
	ERROR(error.what() << endl);
      }
    }
  }
    
  if (numberOfEvents > 0) {
  
    JTimer timer;
    
    timer.reset();
    
    for (int counter = 0; counter != numberOfEvents; ++counter) {
      
      if (counter%1000== 0) { 
	STATUS(setw(10) << counter << '\r'); DEBUG(endl);
      }
      
      timer.start();
      
      for (int i = 0; i != N; ++i) {

	try {
	
	  double npe = cdf[i].getNPE(R, dir.getTheta(), dir.getPhi());

	  if        (is_bremsstrahlung(type[i])) {
	    npe *= E;
	  } else if (is_deltarays(type[i])) {
	    npe *= getDeltaRaysFromMuon(E);
	  }

	  for (int j = gRandom->Poisson(npe); j != 0; --j) {
	  
	    const double x = gRandom->Rndm();
	    const double t = cdf[i].getTime(R, dir.getTheta(), dir.getPhi(), x);
	  
	    h0.Fill(t + t0);
	  }
	}
	catch(const exception& error) {
	  NOTICE(error.what() << endl);
	}
      }
      
      timer.stop();
    }
    STATUS(endl);
  
    const double w = 1.0 / (double) numberOfEvents;
    
    if (debug > JEEP::status_t) {
      timer.print(cout, w);
    }

    // normalise histogram (dP/dt)
    
    for (int j = 1; j <= h0.GetNbinsX(); ++j) {
      
      const double y  = h0.GetBinContent(j);
      const double z  = h0.GetBinError  (j);
      const double dx = h0.GetBinWidth  (j);
      
      h0.SetBinContent(j, y / (dx*numberOfEvents));
      h0.SetBinError  (j, z / (dx*numberOfEvents));
    }
  }

  TFile out(outputFile.c_str(), "recreate");

  out << h0 << H1;
  
  out.Write();
  out.Close();
}