/*
  ---- FastSim ----
  A Fast Simulator for general purpose LHC detector
  S. Ovyn ~~~~ severine.ovyn@uclouvain.be

  Center for Particle Physics and Phenomenology (CP3)
  Universite Catholique de Louvain (UCL)
  Louvain-la-Neuve, Belgium
*/

/// \file Smearing.cpp
/// \brief executable for the FastSim

#include "TChain.h"
#include "TApplication.h"

#include "Utilities/ExRootAnalysis/interface/ExRootTreeReader.h"
#include "Utilities/ExRootAnalysis/interface/ExRootTreeWriter.h"
#include "Utilities/ExRootAnalysis/interface/ExRootTreeBranch.h"

#include "H_BeamParticle.h"
#include "H_BeamLine.h"
#include "H_RomanPot.h"

#include "interface/DataConverter.h"
#include "interface/HEPEVTConverter.h"
#include "interface/LHEFConverter.h"
#include "interface/STDHEPConverter.h"

#include "interface/SmearUtil.h"
#include "interface/JetUtils.h"
#include "interface/BFieldProp.h"

#include "Utilities/Fastjet/include/fastjet/PseudoJet.hh"
#include "Utilities/Fastjet/include/fastjet/ClusterSequence.hh"

#include<vector>
#include<iostream>

#include "interface/TreeClasses.h"
using namespace std;

//------------------------------------------------------------------------------

// //********************************** PYTHIA INFORMATION*********************************

TSimpleArray<TRootGenParticle> TauHadr(const TClonesArray *GEN)
 {
   TIter it((TCollection*)GEN);
   it.Reset();
   TRootGenParticle *gen1;
   TSimpleArray<TRootGenParticle> array,array2;

   while((gen1 = (TRootGenParticle*) it.Next()))
      {
        array.Add(gen1);
      }
   it.Reset();
   bool tauhad;
   while((gen1 = (TRootGenParticle*) it.Next()))
    {
       tauhad=false;
       if(abs(gen1->PID)==15)
         {
            int d1=gen1->D1;
            int d2=gen1->D2;

            if((d1 < array.GetEntries()) && (d1 > 0) && (d2 < array.GetEntries()) && (d2 > 0))
               {
                 tauhad=true;
                 for(int d=d1; d < d2+1; d++)
                    {
                      if(abs(array[d]->PID)== pE || abs(array[d]->PID)== pMU)tauhad=false;
                    }
               }
         }
        if(tauhad)array2.Add(gen1);
     }
   return array2;
 }



void PairingJet(TLorentzVector &JETSm, const TLorentzVector &JET,  vector<fastjet::PseudoJet> sorted_jetsS)
{
  JETSm.SetPxPyPzE(0,0,0,0);
  float deltaRtest=5000;
  for (unsigned int i = 0; i < sorted_jetsS.size(); i++) {
      TLorentzVector Att;
      Att.SetPxPyPzE(sorted_jetsS[i].px(),sorted_jetsS[i].py(),sorted_jetsS[i].pz(),sorted_jetsS[i].E());
      if(DeltaR(JET.Phi(),JET.Eta(),Att.Phi(),Att.Eta()) < deltaRtest)
        {
          deltaRtest = DeltaR(JET.Phi(),JET.Eta(),Att.Phi(),Att.Eta());
          if(deltaRtest < 0.25)
             {
               JETSm = Att;
             }
        }
    }
}

int main(int argc, char *argv[])
{
  int appargc = 2;
  char *appName = "Smearing";
  char *appargv[] = {appName, "-b"};
  TApplication app(appName, &appargc, appargv);
  
  if(argc != 4 && argc != 3) {
      cout << " Usage: " << argv[0] << " input_file" << " output_file" << " data_card " << endl;
      cout << " input_list - list of files in Ntpl, StdHep of LHEF format," << endl;
      cout << " output_file - output file." << endl;
      cout << " data_card - Datacard containing resolution variables for the detector simulation (optional) "<<endl;
      exit(1);
  }

  srand (time (NULL));         /* Initialisation du générateur */
  
  //read the input TROOT file
  string inputFileList(argv[1]), outputfilename(argv[2]);
  if(outputfilename.find(".root") > outputfilename.length() ) {
    cout << "output_file should be a .root file!\n";
    return -1;
  }

  TFile *outputFile = TFile::Open(outputfilename.c_str(), "RECREATE"); // Creates the file, but should be closed just after
  outputFile->Close();
  
  string line;
  ifstream infile(inputFileList.c_str());
  infile >> line; // the first line determines the type of input files
  
  DataConverter *converter=0;
  
  if(strstr(line.c_str(),".hep"))
    {                           
      cout<<"*************************************************************************"<<endl;
      cout<<"************         StdHEP file format detected           **************"<<endl;
      cout<<"************     Starting convertion to TRoot format       **************"<<endl;
      cout<<"*************************************************************************"<<endl;
      converter = new STDHEPConverter(inputFileList,outputfilename);//case ntpl file in input list
    }
  else if(strstr(line.c_str(),".lhe"))
    {
      cout<<"*************************************************************************"<<endl;
      cout<<"************          LHEF file format detected            **************"<<endl;
      cout<<"************     Starting convertion to TRoot format       **************"<<endl;
      cout<<"*************************************************************************"<<endl;
      converter = new LHEFConverter(inputFileList,outputfilename);//case ntpl file in input list
    }
  else if(strstr(line.c_str(),".root"))
    {
      cout<<"*************************************************************************"<<endl;
      cout<<"************         h2root file format detected           **************"<<endl;
      cout<<"************     Starting convertion to TRoot format       **************"<<endl;
      cout<<"*************************************************************************"<<endl;
      converter = new HEPEVTConverter(inputFileList,outputfilename);//case ntpl file in input list
    }
  else { cout << "***  " << line.c_str() << "\n***  file format not identified\n***  Exiting\n"; return -1;};
  
  TChain chain("GEN");
  chain.Add(outputfilename.c_str());
  ExRootTreeReader *treeReader = new ExRootTreeReader(&chain);
  const TClonesArray *branchGen = treeReader->UseBranch("Particle");
  TIter itGen((TCollection*)branchGen);
  
  //write the output root file
  ExRootTreeWriter *treeWriter = new ExRootTreeWriter(outputfilename, "Analysis");
  ExRootTreeBranch *branchjet = treeWriter->NewBranch("JetPTResol", RESOLJET::Class());
  ExRootTreeBranch *branchelec = treeWriter->NewBranch("ElecEResol", RESOLELEC::Class());
  ExRootTreeBranch *branchmuon = treeWriter->NewBranch("MuonPTResol", RESOLMUON::Class());
  ExRootTreeBranch *branchtaujet = treeWriter->NewBranch("TauJetPTResol", TAUHAD::Class());
  ExRootTreeBranch *branchetmis = treeWriter->NewBranch("ETmisResol",ETMIS::Class());
  
  TRootGenParticle *particle;
  
  RESOLELEC * elementElec;
  RESOLMUON *elementMuon;
  RESOLJET *elementJet;
  TAUHAD *elementTaujet;
  ETMIS *elementEtmis;
  
  
  //read the datacard input file
  string DetDatacard("data/DataCardDet.dat");
  if(argc==4)  DetDatacard =argv[3];
  RESOLution *DET = new RESOLution();   
  DET->ReadDataCard(DetDatacard);

  //Jet information
  JetsUtil *JETRUN = new JetsUtil();

  //Propagation of tracks in the B field
  TrackPropagation *TRACP = new TrackPropagation();
   
  TLorentzVector genMomentum(0,0,0,0);//TLorentzVector containing generator level information
  TLorentzVector recoMomentum(0,0,0,0);//TLorentzVector containing Reco level information
  LorentzVector jetMomentum;
  vector<TLorentzVector> TrackCentral;
  
  vector<fastjet::PseudoJet> input_particlesGEN;//for FastJet algorithm
  vector<fastjet::PseudoJet> sorted_jetsGEN;
  
  vector<fastjet::PseudoJet> input_particlesReco;//for FastJet algorithm
  vector<fastjet::PseudoJet> sorted_jetsReco;

  vector<PhysicsTower> towers;
  
  // Loop over all events
  Long64_t entry, allEntries = treeReader->GetEntries();
  cout << "** Chain contains " << allEntries << " events" << endl;
  for(entry = 0; entry < allEntries; ++entry)
    {
      TLorentzVector PTmisReco(0,0,0,0);
      TLorentzVector PTmisGEN(0,0,0,0);
      treeReader->ReadEntry(entry);
      treeWriter->Clear();
      if((entry % 100) == 0 && entry > 0 )  cout << "** Processing element # " << entry << endl;
      
      TSimpleArray<TRootGenParticle> bGen;
      itGen.Reset();
      TrackCentral.clear();
      TSimpleArray<TRootGenParticle> NFCentralQ;
      
      input_particlesReco.clear();
      input_particlesGEN.clear();
      towers.clear();
      
      // Loop over all particles in event
      while( (particle = (TRootGenParticle*) itGen.Next()) )
	{
          genMomentum.SetPxPyPzE(particle->Px, particle->Py, particle->Pz, particle->E);
	  
	  int pid = abs(particle->PID);
	  float eta = fabs(particle->Eta);
	  
          //input generator level particle for jet algorithm	  
          if(particle->Status == 1 && eta < DET->MAX_CALO_FWD)
	    {
	      input_particlesGEN.push_back(fastjet::PseudoJet(genMomentum.Px(),genMomentum.Py(),genMomentum.Pz(), genMomentum.E()));
	    }
	  
	  //Calculate ETMIS from generated particles
          if((pid == pNU1) || (pid == pNU2) || (pid == pNU3))PTmisGEN = PTmisGEN + genMomentum;
	  
	  if( (particle->Status == 1)    &&
              ((pid != pNU1) && (pid != pNU2) && (pid != pNU3)) &&
              (fabs(particle->Eta) < DET->MAX_CALO_FWD)
	      )
            {
              recoMomentum = genMomentum;          
              //use of the magnetic field propagation
              TRACP->Propagation(particle,recoMomentum);
	      //              cout<<"eta "<<eta<<endl;
              eta=fabs(recoMomentum.Eta());
	      //            cout<<"eta apres"<<eta<<endl;
	      
	      switch(pid) {
		
	      case pE: // all electrons with eta < DET->MAX_CALO_FWD
                DET->SmearElectron(recoMomentum);
                if(recoMomentum.E() !=0 && eta < DET->MAX_TRACKER){
		  elementElec=(RESOLELEC*) branchelec->NewEntry();
		  elementElec->E = genMomentum.E();
		  elementElec->SmearedE = recoMomentum.E();}
		break; // case pE
	      case pGAMMA: // all photons with eta < DET->MAX_CALO_FWD
		DET->SmearElectron(recoMomentum);
		break; // case pGAMMA
	      case pMU: // all muons with eta < DET->MAX_MU
		DET->SmearMu(recoMomentum);
                if(recoMomentum.E() !=0){
                elementMuon = (RESOLMUON*) branchmuon->NewEntry();
                elementMuon->OverPT = (1/genMomentum.Pt());
                elementMuon->OverSmearedPT = (1/recoMomentum.Pt());}
		break; // case pMU
	      case pLAMBDA: // all lambdas with eta < DET->MAX_CALO_FWD
	      case pK0S:    // all K0s with eta < DET->MAX_CALO_FWD
		DET->SmearHadron(recoMomentum, 0.7);
		break; // case hadron
	      default:   // all other final particles with eta < DET->MAX_CALO_FWD
		DET->SmearHadron(recoMomentum, 1.0);
		break;
	      } // switch (pid)
	      
	      //information to reconstruct jets from reconstructed towers
	      int charge=Charge(pid);
	      if(recoMomentum.E() !=0 && pid != pMU) {
		if(charge == 0 || (charge !=0 && recoMomentum.Pt() >= DET->PT_TRACKS_MIN)){
		  towers.push_back(PhysicsTower(LorentzVector(recoMomentum.Px(),recoMomentum.Py(),recoMomentum.Pz(), recoMomentum.E())));
		  input_particlesReco.push_back(fastjet::PseudoJet(recoMomentum.Px(),recoMomentum.Py(),recoMomentum.Pz(), recoMomentum.E()));
		}
	      }
	      
	      // all final charged particles
	      if(
		 (genMomentum.E()!=0) &&
		 (fabs(genMomentum.Eta()) < DET->MAX_TRACKER) &&
		 (genMomentum.Pt() > DET->PT_TRACKS_MIN ) &&     // pt too small to be taken into account
		 ((rand()%100) < DET->TRACKING_EFF)  &&
		 (charge!=0)
		 )
		{TrackCentral.push_back(genMomentum);}
	      
	    } // switch
	} // while
      
      //compute missing transverse energy from calo towers    
      TLorentzVector Att(0.,0.,0.,0.);
      float ScalarEt=0;
      for(unsigned int i=0; i < towers.size(); i++) 
	{
	  Att.SetPxPyPzE(towers[i].fourVector.px,towers[i].fourVector.py,towers[i].fourVector.pz,towers[i].fourVector.E);
	  ScalarEt = ScalarEt + Att.Et();
	  PTmisReco = PTmisReco + Att;
	}
      
      elementEtmis= (ETMIS*) branchetmis->NewEntry();
      elementEtmis->Et = (PTmisGEN).Pt();
      elementEtmis->Ex = (-PTmisGEN).Px();
      elementEtmis->SEt = ScalarEt;

      elementEtmis->EtSmeare = (PTmisReco).Pt()-(PTmisGEN).Pt();
      elementEtmis->ExSmeare = (-PTmisReco).Px()-(PTmisGEN).Px();

      //*****************************
      
      sorted_jetsGEN=JETRUN->RunJets(input_particlesGEN);
      sorted_jetsReco=JETRUN->RunJets(input_particlesReco);

      TSimpleArray<TRootGenParticle> TausHadr = TauHadr(branchGen);

      TLorentzVector JETreco(0,0,0,0);
      for (unsigned int i = 0; i < sorted_jetsGEN.size(); i++) {
        TLorentzVector JETgen(0,0,0,0);
        JETgen.SetPxPyPzE(sorted_jetsGEN[i].px(),sorted_jetsGEN[i].py(),sorted_jetsGEN[i].pz(),sorted_jetsGEN[i].E());
        PairingJet(JETreco,JETgen,sorted_jetsReco);
        if(JETreco.Pt()>1)
          {
            elementJet= (RESOLJET*) branchjet->NewEntry();
            elementJet->PT = JETgen.Et();
            elementJet->SmearedPT = JETreco.Et()/JETgen.Et();
          }
      }
      for (unsigned int i = 0; i < sorted_jetsReco.size(); i++) {
        TLorentzVector JETT(0,0,0,0);
        JETT.SetPxPyPzE(sorted_jetsReco[i].px(),sorted_jetsReco[i].py(),sorted_jetsReco[i].pz(),sorted_jetsReco[i].E());
        if(fabs(JETT.Eta()) < (DET->MAX_TRACKER - DET->TAU_CONE_TRACKS)) 
           {
            for(Int_t i=0; i<TausHadr.GetEntries();i++)
              {
                if(DeltaR(TausHadr[i]->Phi,TausHadr[i]->Eta,JETT.Phi(),JETT.Eta())<0.1)
                  {
                    elementTaujet= (TAUHAD*) branchtaujet->NewEntry();
                    elementTaujet->EnergieCen = (DET->EnergySmallCone(towers,JETT.Eta(),JETT.Phi())/JETT.E());
                    elementTaujet->NumTrack = DET->NumTracks(TrackCentral,DET->PT_TRACK_TAU,JETT.Eta(),JETT.Phi());
                 }
              }
           }
         
	
      } // for itJet : loop on all jets
      
      treeWriter->Fill();
    } // Loop over all events
  treeWriter->Write();
  
  cout << "** Exiting..." << endl;
  
  delete treeWriter;
  delete treeReader;
  delete DET;
  if(converter) delete converter;
}