/*
  ---- Delphes ----
  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 Delphes.cpp
/// \brief executable for the Delphes

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

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

#include <vector>
#include <iostream>

using namespace std;

//------------------------------------------------------------------------------
void todo(string filename) {
  ifstream infile(filename.c_str());
  cout << "** TODO list ..." << endl;
  while(infile.good()) {
	string temp;
	getline(infile,temp);
	cout << "*" << temp << endl;
  }
  cout << "** done...\n"; 
}

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

int main(int argc, char *argv[])
{
  int appargc = 2;
  char *appName = "Delphes";
  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"; 
  	exit(1);
  }
  //create output log-file name
  string forLog = outputfilename;
  string LogName = forLog.erase(forLog.find(".root"));
  LogName = LogName+"_run.log";

  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

  //read the datacard input file
  string DetDatacard("");
  if(argc==4)  DetDatacard =argv[3];

  //Smearing information
  RESOLution *DET = new RESOLution();
  DET->ReadDataCard(DetDatacard);
  DET->Logfile(LogName);

  //Trigger information
  Trigger *TRIG = new Trigger();
  TRIG->TriggerReader("data/trigger.dat");

  //Propagation of tracks in the B field
  TrackPropagation *TRACP = new TrackPropagation(); 

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

  //VFD information
  VeryForward * VFD = new VeryForward();

  //todo(LogName.c_str());
 
  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("Jet", TRootJet::Class());
  ExRootTreeBranch *branchTauJet = treeWriter->NewBranch("TauJet", TRootTauJet::Class());
  ExRootTreeBranch *branchElectron = treeWriter->NewBranch("Electron", TRootElectron::Class());
  ExRootTreeBranch *branchMuon = treeWriter->NewBranch("Muon", TRootMuon::Class());
  ExRootTreeBranch *branchPhoton = treeWriter->NewBranch("Photon", TRootPhoton::Class());
  ExRootTreeBranch *branchTracks = treeWriter->NewBranch("Tracks", TRootTracks::Class());
  ExRootTreeBranch *branchETmis = treeWriter->NewBranch("ETmis", TRootETmis::Class());
  ExRootTreeBranch *branchCalo = treeWriter->NewBranch("CaloTower", TRootCalo::Class());
  ExRootTreeBranch *branchZDC = treeWriter->NewBranch("ZDChits", TRootZdcHits::Class());
  ExRootTreeBranch *branchRP220 = treeWriter->NewBranch("RP220hits", TRootRomanPotHits::Class());
  ExRootTreeBranch *branchFP420 = treeWriter->NewBranch("FP420hits", TRootRomanPotHits::Class());
  
  
  TRootGenParticle *particle; 
  TRootETmis *elementEtmis;
  TRootElectron *elementElec;
  TRootMuon *elementMu;
  TRootPhoton *elementPhoton;
  TRootTracks *elementTracks;
  TRootCalo *elementCalo;
  
  TLorentzVector genMomentum(0,0,0,0);
  TLorentzVector genMomentumCalo(0,0,0,0);
  LorentzVector jetMomentum;
 
  vector<fastjet::PseudoJet> input_particles;//for FastJet algorithm
  vector<fastjet::PseudoJet> sorted_jets;

  vector<TLorentzVector> TrackCentral;  
  vector<PhysicsTower> towers;
  
  vector<TLorentzVector> electron;
  vector<int> elecPID;
  vector<TLorentzVector> muon;
  vector<int> muonPID;
  TSimpleArray<TRootGenParticle> NFCentralQ;
  


  // Loop over all events
  Long64_t entry, allEntries = treeReader->GetEntries();
  cout << "** Chain contains " << allEntries << " events" << endl;
  for(entry = 0; entry < allEntries; ++entry)
    {
      TLorentzVector PTmis(0,0,0,0);
      treeReader->ReadEntry(entry);
      treeWriter->Clear();
      if((entry % 100) == 0 && entry > 0 )  cout << "** Processing element # " << entry << endl;
      
      electron.clear();
      muon.clear();
      elecPID.clear();
      muonPID.clear();
      NFCentralQ.Clear();
      
      itGen.Reset();
      TrackCentral.clear();
      towers.clear();
      input_particles.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(genMomentum.Eta());

          //subarray of the quarks (i.e. not final particles, i.e status not equal to 1) 
          // in the tracker (i.e. for those we know the tracks)
          // with enough p_T
          //// This subarray is needed for the B-jet algorithm
	  // optimization for speed : put first PID condition, then ETA condition, then either pt or status
	  if( (pid <= pB || pid == pGLUON) &&// is it a light quark or a gluon, i.e. is it one of these : u,d,c,s,b,g ?
              eta < DET->MAX_TRACKER &&
              particle->Status != 1 &&
              particle->PT > DET->PT_QUARKS_MIN ) {
            NFCentralQ.Add(particle);
          }
	  
	  
	  // keeps only final particles, visible by the central detector, including the fiducial volume
	  // the ordering of conditions have been optimised for speed : put first the STATUS condition
	  //
	  // 
          if( (particle->Status == 1)    &&
	      ( 
	       (pid == pMU  && eta < DET->MAX_MU) ||
	       (pid != pMU  && (pid != pNU1) && (pid != pNU2) && (pid != pNU3) && eta < DET->MAX_CALO_FWD) 
		)
	      ) { 
          //  TRACP->Propagation(particle,genMomentum);
	    eta = fabs(genMomentum.Eta());
            switch(pid) {
	      
	    case pE: // all electrons with eta < DET->MAX_CALO_FWD
              DET->SmearElectron(genMomentum);
	      electron.push_back(genMomentum);
              elecPID.push_back(particle->PID);
	      break; // case pE
	    case pGAMMA: // all photons with eta < DET->MAX_CALO_FWD
	      DET->SmearElectron(genMomentum);
	      if(genMomentum.E()!=0 && eta < DET->MAX_TRACKER) {
		elementPhoton = (TRootPhoton*) branchPhoton->NewEntry();
		elementPhoton->Set(genMomentum);
	      }
	      break; // case pGAMMA
	    case pMU: // all muons with eta < DET->MAX_MU
	      DET->SmearMu(genMomentum);
              muonPID.push_back(particle->PID);
	      muon.push_back(genMomentum);
	      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(genMomentum, 0.7);
	      break; // case hadron
	    default:   // all other final particles with eta < DET->MAX_CALO_FWD
	      DET->SmearHadron(genMomentum, 1.0);
	      break;
	    } // switch (pid)
	    
	    // all final particles but muons and neutrinos	
	    // for calorimetric towers and mission PT
	    
	    if(genMomentum.E() !=0) {
	      if(pid !=pMU) {
                PhysicsTower CaloTower = PhysicsTower(LorentzVector(genMomentum.Px(),genMomentum.Py(),genMomentum.Pz(), genMomentum.E()));
    		towers.push_back(CaloTower);
		// create a fastjet::PseudoJet with these components and put it onto
		// back of the input_particles vector
		input_particles.push_back(fastjet::PseudoJet(genMomentum.Px(),genMomentum.Py(),genMomentum.Pz(), genMomentum.E())); 
                //genMomentumCalo.SetPtEtaPhiE(CaloTower.Et(),CaloTower.iEta(),CaloTower.iPhi(),CaloTower.fourVector.E);
                genMomentumCalo.SetPxPyPzE(CaloTower.fourVector.px,CaloTower.fourVector.py,CaloTower.fourVector.pz,CaloTower.fourVector.E);
		elementCalo = (TRootCalo*) branchCalo->NewEntry();
		elementCalo->Set(genMomentumCalo);
	      }
	    }
	    
	    // all final charged particles
	    if(
	       ((rand()%100) < DET->TRACKING_EFF)  &&
	       (genMomentum.E()!=0) &&
	       (fabs(genMomentum.Eta()) < DET->MAX_TRACKER) && 
	       (genMomentum.Pt() > DET->PT_TRACKS_MIN ) &&     // pt too small to be taken into account
	       (pid != pGAMMA)    && 
	       (pid != pPI0)      &&
	       (pid != pK0L)      &&
	       (pid != pN)        &&
	       (pid != pSIGMA0)   &&
	       (pid != pDELTA0)   &&
	       (pid != pK0S)   // not charged particles : invisible by tracker
	       )
	      {
		elementTracks = (TRootTracks*) branchTracks->NewEntry();
		elementTracks->Set(genMomentum);
		TrackCentral.push_back(genMomentum);
	      }
	    
	  } // switch
	  
          VFD->ZDC(treeWriter,branchZDC,particle);
          VFD->RomanPots(treeWriter,branchRP220,branchFP420,particle);
	  
	} // while
      
      for(unsigned int i=0; i < electron.size(); i++) {
	if(electron[i].E()!=0 && fabs(electron[i].Eta()) < DET->MAX_TRACKER && electron[i].Pt() > DET->ELEC_pt)
	  {
	    elementElec = (TRootElectron*) branchElectron->NewEntry();
	    elementElec->Set(electron[i]);
	    elementElec->Charge = sign(elecPID[i]);
	    elementElec->IsolFlag = DET->Isolation(electron[i].Phi(),electron[i].Eta(),TrackCentral,2.0);
	  }
      }
      for(unsigned int i=0; i < muon.size(); i++) {
	if(muon[i].E()!=0 && fabs(muon[i].Eta()) < DET->MAX_MU && muon[i].Pt() > DET->MUON_pt) 
	  {
	    elementMu = (TRootMuon*) branchMuon->NewEntry();
	    elementMu->Charge = sign(muonPID[i]);
	    elementMu->Set(muon[i]);
	    elementMu->IsolFlag = DET->Isolation(muon[i].Phi(),muon[i].Eta(),TrackCentral,2.0);
	  }
      }
      
      // computes the Missing Transverse Momentum
      TLorentzVector Att(0.,0.,0.,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);
          PTmis = PTmis + Att;
        }
      elementEtmis = (TRootETmis*) branchETmis->NewEntry();
      elementEtmis->ET = (PTmis).Pt();
      elementEtmis->Phi = (-PTmis).Phi();
      elementEtmis->Px = (-PTmis).Px();
      elementEtmis->Py = (-PTmis).Py();
      //*****************************
      
      sorted_jets=JETRUN->RunJets(input_particles);
      JETRUN->RunJetBtagging(treeWriter, branchJet,sorted_jets,NFCentralQ);
      JETRUN->RunTauJets(treeWriter,branchTauJet,sorted_jets,towers, TrackCentral);


      treeWriter->Fill();

      // Add here the trigger
      // Should test all the trigger table on the event, based on reconstructed objects
      
 //     Trigger *TRIG = new Trigger();
 //     TRIG->TriggerReader("data/trigger.dat");
     
    } // Loop over all events

  treeWriter->Write();
  
  cout << "** Exiting..." << endl;
  
  delete treeWriter;
  delete treeReader;
  delete DET;
  if(converter) delete converter;

  todo("TODO");
}