/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *               
 *                                                                        *               
 * Author: The ALICE Off-line Project.                                    *               
 * Contributors are mentioned in the code where appropriate.              *               
 *                                                                        *               
 * Permission to use, copy, modify and distribute this software and its   *               
 * documentation strictly for non-commercial purposes is hereby granted   *               
 * without fee, provided that the above copyright notice appears in all   *               
 * copies and that both the copyright notice and this permission notice   *               
 * appear in the supporting documentation. The authors make no claims     *               
 * about the suitability of this software for any purpose. It is          *               
 * provided "as is" without express or implied warranty.                  *               
 **************************************************************************/


////////////////////////////////////////////////////////////////////////
//                                                                    //
//  Task for Heavy Flavour Electron-Hadron DeltaPhi Correlation       //
//  Non-Photonic Electron identified with Invariant mass              //
//  analysis methos in function  SelectPhotonicElectron               //
//  DeltaPhi calculated in function  ElectronHadCorrel                // 
//                                                                    //
//  Author: Deepa Thomas (Utrecht University)                         //
//                                                                    //
////////////////////////////////////////////////////////////////////////

#include "TChain.h"
#include "TTree.h"
#include "TH2F.h"
#include "TMath.h"
#include "TCanvas.h"
#include "THnSparse.h"
#include "TLorentzVector.h"
#include "TString.h"
#include "TFile.h"

#include "AliAnalysisTask.h"
#include "AliAnalysisManager.h"

#include "AliESDEvent.h"
#include "AliESDHandler.h"
#include "AliAODEvent.h"
#include "AliAODHandler.h"

#include "AliAnalysisTaskElecHadronCorrel.h"
#include "TGeoGlobalMagField.h"
#include "AliLog.h"
#include "AliAnalysisTaskSE.h"
#include "TRefArray.h"
#include "TVector.h"
#include "AliESDInputHandler.h"
#include "AliESDpid.h"
#include "AliESDtrackCuts.h"
#include "AliPhysicsSelection.h"
#include "AliESDCaloCluster.h"
#include "AliAODCaloCluster.h"
#include "AliEMCALRecoUtils.h"
#include "AliEMCALGeometry.h"
#include "AliGeomManager.h"
#include "stdio.h"
#include "TGeoManager.h"
#include "iostream"
#include "fstream"

#include "AliEMCALTrack.h"
#include "AliMagF.h"

#include "AliKFParticle.h"
#include "AliKFVertex.h"

#include "AliPID.h"
#include "AliPIDResponse.h"
#include "AliHFEcontainer.h"
#include "AliHFEcuts.h"
#include "AliHFEpid.h"
#include "AliHFEpidBase.h"
#include "AliHFEpidQAmanager.h"
#include "AliHFEtools.h"
#include "AliCFContainer.h"
#include "AliCFManager.h"

ClassImp(AliAnalysisTaskElecHadronCorrel)
//________________________________________________________________________
AliAnalysisTaskElecHadronCorrel::AliAnalysisTaskElecHadronCorrel(const char *name) 
  : AliAnalysisTaskSE(name)
  ,fESD(0)
  ,fGeom(0)
  ,fOutputList(0)
  ,fTrackCuts1(0)
  ,fTrackCuts2(0)
  ,fCuts(0)
  ,fIdentifiedAsOutInz(kFALSE)
  ,fPassTheEventCut(kFALSE)
  ,fRejectKinkMother(kFALSE)
  ,fVz(0.0)
  ,fCFM(0)	
  ,fPID(0)
  ,fPIDqa(0)	       
  ,fOpeningAngleCut(0.1)
  ,fInvmassCut(0.01)	
  ,fNoEvents(0)
  ,fTrkpt(0)
  ,fTrkEovPBef(0)	 
  ,fTrkEovPAft(0)	
  ,fdEdxBef(0)	 
  ,fdEdxAft(0)	 
  ,fInvmassLS(0)		
  ,fInvmassULS(0)		
  ,fOpeningAngleLS(0)	
  ,fOpeningAngleULS(0)	
  ,fSemiIncElecDphi(0) 	
  ,fPhotElecDphi(0)  	
  ,fInclusiveElecDphi(0)  	
  ,fDphiMassHigh(0)		
  ,fDphiULSMassLow(0)	
  ,fDphiLSMassLow(0)
  ,fPhotoElecPt(0)
  ,fSemiInclElecPt(0)
  ,fTrackPtBefTrkCuts(0)	 
  ,fTrackPtAftTrkCuts(0)
  ,fTPCnsigma(0)	 
{
  //Named constructor
  
  fPID = new AliHFEpid("hfePid");
  fTrackCuts1 = new AliESDtrackCuts();
  fTrackCuts2 = new AliESDtrackCuts();  

  // Define input and output slots here
  // Input slot #0 works with a TChain
  DefineInput(0, TChain::Class());
  // Output slot #0 id reserved by the base class for AOD
  // Output slot #1 writes into a TH1 container
  // DefineOutput(1, TH1I::Class());
  DefineOutput(1, TList::Class());
  //  DefineOutput(3, TTree::Class());
}

//________________________________________________________________________
AliAnalysisTaskElecHadronCorrel::AliAnalysisTaskElecHadronCorrel() 
  : AliAnalysisTaskSE("DefaultAnalysis_AliAnalysisElecHadCorrel")
  ,fESD(0)
  ,fGeom(0)  
  ,fOutputList(0)
  ,fTrackCuts1(0)
  ,fTrackCuts2(0)
  ,fCuts(0)
  ,fIdentifiedAsOutInz(kFALSE)
  ,fPassTheEventCut(kFALSE)
  ,fRejectKinkMother(kFALSE)
  ,fVz(0.0)
  ,fCFM(0)	
  ,fPID(0)       
  ,fPIDqa(0)	       
  ,fOpeningAngleCut(0.1)
  ,fInvmassCut(0.01)	
  ,fNoEvents(0)
  ,fTrkpt(0)
  ,fTrkEovPBef(0)	 
  ,fTrkEovPAft(0)	 
  ,fdEdxBef(0)	 
  ,fdEdxAft(0)	 
  ,fInvmassLS(0)		
  ,fInvmassULS(0)		
  ,fOpeningAngleLS(0)	
  ,fOpeningAngleULS(0)	
  ,fSemiIncElecDphi(0) 	
  ,fPhotElecDphi(0)  	
  ,fInclusiveElecDphi(0)  	
  ,fDphiMassHigh(0)		
  ,fDphiULSMassLow(0)	
  ,fDphiLSMassLow(0)
  ,fPhotoElecPt(0)
  ,fSemiInclElecPt(0)
  ,fTrackPtBefTrkCuts(0)	 
  ,fTrackPtAftTrkCuts(0)	 	  
  ,fTPCnsigma(0)	 
{
	//Default constructor
	fPID = new AliHFEpid("hfePid");

	fTrackCuts1 = new AliESDtrackCuts();
	fTrackCuts2 = new AliESDtrackCuts();

	// Constructor
	// Define input and output slots here
	// Input slot #0 works with a TChain
	DefineInput(0, TChain::Class());
	// Output slot #0 id reserved by the base class for AOD
	// Output slot #1 writes into a TH1 container
	// DefineOutput(1, TH1I::Class());
	DefineOutput(1, TList::Class());
	//DefineOutput(3, TTree::Class());
}
//_________________________________________

AliAnalysisTaskElecHadronCorrel::~AliAnalysisTaskElecHadronCorrel()
{
  //Destructor 
  
  delete fOutputList;
  delete fGeom;
  delete fPID;
  delete fCFM;
  delete fPIDqa;
  delete fTrackCuts1;
  delete fTrackCuts2;
}
//_________________________________________

void AliAnalysisTaskElecHadronCorrel::UserExec(Option_t*)
{
  //Main loop
  //Called for each event
  
  // create pointer to event
  fESD = dynamic_cast<AliESDEvent*>(InputEvent());
  if (!fESD) {
    printf("ERROR: fESD not available\n");
    return;
  }
  
  if(!fCuts){
    AliError("HFE cuts not available");
    return;
  }
  
  if(!fPID->IsInitialized()){ 
    // Initialize PID with the given run number
    AliWarning("PID not initialised, get from Run no");
    fPID->InitializePID(fESD->GetRunNumber());
  }
  
  //-------trigger selection
  UInt_t res = ((AliInputEventHandler*)(AliAnalysisManager::GetAnalysisManager()->GetInputEventHandler()))->IsEventSelected();
  if (res==0)
    return;
  
  if( (((AliInputEventHandler*)(AliAnalysisManager::GetAnalysisManager()->GetInputEventHandler()))->IsEventSelected() & AliVEvent::kFastOnly) )
    return;
  
  if(!(((AliInputEventHandler*)(AliAnalysisManager::GetAnalysisManager()->GetInputEventHandler()))->IsEventSelected() & AliVEvent::kEMC1) ) return;
  //if(!(((AliInputEventHandler*)(AliAnalysisManager::GetAnalysisManager()->GetInputEventHandler()))->IsEventSelected() & AliVEvent::kMB) ) return;
  
  Int_t fNOtrks =  fESD->GetNumberOfTracks();
  const AliESDVertex *pVtx = fESD->GetPrimaryVertex();
  
  Double_t pVtxZ = -999;
  pVtxZ = pVtx->GetZ();
  
  // Event cut
  //	if(!fCFM->CheckEventCuts(AliHFEcuts::kEventStepReconstructed, fESD)) return;
  
  //Check if its an LED event 
  if(IsLEDEvent()) return;
  
  if(TMath::Abs(pVtxZ)>10) return;
  fNoEvents->Fill(0);
  
  if(fNOtrks<2) return;
  
  AliPIDResponse *pidResponse = fInputHandler->GetPIDResponse();
  if(!pidResponse){
    AliDebug(1, "Using default PID Response");
    pidResponse = AliHFEtools::GetDefaultPID(kFALSE, fInputEvent->IsA() == AliAODEvent::Class()); 
  }
  
  fPID->SetPIDResponse(pidResponse);
  
  fCFM->SetRecEventInfo(fESD);
  
  // Track loop 
  for (Int_t iTracks = 0; iTracks < fESD->GetNumberOfTracks(); iTracks++) {
    AliESDtrack* track = fESD->GetTrack(iTracks);
    if (!track) {
      printf("ERROR: Could not receive track %d\n", iTracks);
      continue;
    }
    
    fTrackPtBefTrkCuts->Fill(track->Pt());		
    // RecKine: ITSTPC cuts  
    if(!ProcessCutStep(AliHFEcuts::kStepRecKineITSTPC, track)) continue;
    
    //RecKink
    if(fRejectKinkMother) { // Quick and dirty fix to reject both kink mothers and daughters
      if(track->GetKinkIndex(0) != 0) continue;
    } 
    
    // RecPrim
    if(!ProcessCutStep(AliHFEcuts::kStepRecPrim, track)) continue;
    
    // HFEcuts: ITS layers cuts
    if(!ProcessCutStep(AliHFEcuts::kStepHFEcutsITS, track)) continue;
    
    // HFE cuts: TPC PID cleanup
    if(!ProcessCutStep(AliHFEcuts::kStepHFEcutsTPC, track)) continue;
    
    fTrackPtAftTrkCuts->Fill(track->Pt());		
    
    Double_t fClsE = -999, p = -999, fEovP=-999, pt = -999, dEdx=-999, fTPCnSigma=0;
    // Track extrapolation
    Int_t fClsId = track->GetEMCALcluster();
    if(fClsId == -1) continue;
    AliESDCaloCluster *cluster = fESD->GetCaloCluster(fClsId);
    
    pt = track->Pt();
    if(pt<1) continue;
    fTrkpt->Fill(pt);
    fClsE = cluster->E();
    p = track->P();
    dEdx = track->GetTPCsignal();
    fEovP = fClsE/p;
    fTPCnSigma = fPID->GetPIDResponse() ? fPID->GetPIDResponse()->NumberOfSigmasTPC(track, AliPID::kElectron) : 1000;
    fdEdxBef->Fill(p,dEdx);
    fTPCnsigma->Fill(p,fTPCnSigma);
    
    if(fTPCnSigma >= 1.5 && fTPCnSigma <= 3)fTrkEovPBef->Fill(pt,fEovP);
    Int_t pidpassed = 1;
    //--- track accepted, do PID
    AliHFEpidObject hfetrack;
    hfetrack.SetAnalysisType(AliHFEpidObject::kESDanalysis);
    hfetrack.SetRecTrack(track);
    hfetrack.SetPP();
    if(!fPID->IsSelected(&hfetrack, NULL, "", fPIDqa)) pidpassed = 0;
    
    if(pidpassed==0) continue;
    fTrkEovPAft->Fill(pt,fEovP);
    fdEdxAft->Fill(p,dEdx);
    
    Bool_t fFlagPhotonicElec = kFALSE;
    // select photonic electron
    SelectPhotonicElectron(iTracks,track,fFlagPhotonicElec);
    
    //Inclusive electron-hadron correlation
    ElectronHadCorrel(iTracks, track, fInclusiveElecDphi);
    
    // photonic electron
    if(fFlagPhotonicElec){
      //Electron hadron correlation
      ElectronHadCorrel(iTracks, track, fPhotElecDphi);
      fPhotoElecPt->Fill(pt);
    }
    
    // Semi inclusive electron 
    if(!fFlagPhotonicElec){
      //Electron hadron correlation
      ElectronHadCorrel(iTracks, track, fSemiIncElecDphi);
      fSemiInclElecPt->Fill(pt);
    }
  }
  
  
  PostData(1, fOutputList);
}
//_________________________________________
void AliAnalysisTaskElecHadronCorrel::UserCreateOutputObjects()
{
  //Create histograms
  TGeoManager::Import("geometry.root");
  fGeom =  AliEMCALGeometry::GetInstance("EMCAL_COMPLETEV1");
  
  //--------Initialize PID
  fPID->SetHasMCData(kFALSE);
  if(!fPID->GetNumberOfPIDdetectors()) 
    {
      fPID->AddDetector("TPC", 0);
      fPID->AddDetector("EMCAL", 1);
    }
  
  fPID->SortDetectors(); 
  fPIDqa = new AliHFEpidQAmanager();
  fPIDqa->Initialize(fPID);
  
  //--------Initialize correction Framework and Cuts
  fCFM = new AliCFManager;
  const Int_t kNcutSteps = AliHFEcuts::kNcutStepsMCTrack + AliHFEcuts::kNcutStepsRecTrack + AliHFEcuts::kNcutStepsDETrack;
  fCFM->SetNStepParticle(kNcutSteps);
  for(Int_t istep = 0; istep < kNcutSteps; istep++)
    fCFM->SetParticleCutsList(istep, NULL);
  
  if(!fCuts){
    AliWarning("Cuts not available. Default cuts will be used");
    fCuts = new AliHFEcuts;
    fCuts->CreateStandardCuts();
  }
  fCuts->Initialize(fCFM);
  
  //---------Output Tlist
  fOutputList = new TList();
  fOutputList->SetOwner();
  fOutputList->Add(fPIDqa->MakeList("PIDQA"));
  
  fNoEvents = new TH1F("fNoEvents","",1,0,1) ;
  fOutputList->Add(fNoEvents);
  
  fTrkpt = new TH1F("fTrkpt","track pt",1000,0,50);
  fOutputList->Add(fTrkpt);
  
  fTrackPtBefTrkCuts = new TH1F("fTrackPtBefTrkCuts","track pt before track cuts",1000,0,50);
  fOutputList->Add(fTrackPtBefTrkCuts);
  
  fTrackPtAftTrkCuts = new TH1F("fTrackPtAftTrkCuts","track pt after track cuts",1000,0,50);
  fOutputList->Add(fTrackPtAftTrkCuts);
  
  fTPCnsigma = new TH2F("fTPCnsigma", "TPC - n sigma",1000,0,50,200,-10,10);
  fOutputList->Add(fTPCnsigma);
  
  fTrkEovPBef = new TH2F("fTrkEovPBef","track E/p before HFE pid",1000,0,50,100,0,2);
  fOutputList->Add(fTrkEovPBef);
  
  fTrkEovPAft = new TH2F("fTrkEovPAft","track E/p after HFE pid",1000,0,50,100,0,2);
  fOutputList->Add(fTrkEovPAft);
  
  fdEdxBef = new TH2F("fdEdxBef","track dEdx vs p before HFE pid",1000,0,50,150,0,150);
  fOutputList->Add(fdEdxBef);
  
  fdEdxAft = new TH2F("fdEdxAft","track dEdx vs p after HFE pid",1000,0,50,150,0,150);
  fOutputList->Add(fdEdxAft);
  
  fInvmassLS = new TH1F("fInvmassLS", "Inv mass of LS (e,e); mass(GeV/c^2); counts;", 1000,0,0.5);
  fOutputList->Add(fInvmassLS);
  
  fInvmassULS = new TH1F("fInvmassULS", "Inv mass of ULS (e,e); mass(GeV/c^2); counts;", 1000,0,0.5);
  fOutputList->Add(fInvmassULS);
  
  fOpeningAngleLS = new TH1F("fOpeningAngleLS","Opening angle for LS pairs",100,0,1);
  fOutputList->Add(fOpeningAngleLS);
  
  fOpeningAngleULS = new TH1F("fOpeningAngleULS","Opening angle for ULS pairs",100,0,1);
  fOutputList->Add(fOpeningAngleULS);
  
  fSemiIncElecDphi = new TH2F("fSemiIncElecDphi", "Semi Inclusive elec-had Dphi correlation",200,0,20,100,-3.14,3.14);
  fOutputList->Add(fSemiIncElecDphi);
  
  fPhotElecDphi = new TH2F("fPhotElecDphi", "Photon elec-had Dphi correlation",200,0,20,100,-3.14,3.14);
  fOutputList->Add(fPhotElecDphi);
  
  fInclusiveElecDphi = new TH2F("fInclusiveElecDphi", "Inclusive elec-had Dphi correlation",200,0,20,100,-3.14,3.14);
  fOutputList->Add(fInclusiveElecDphi);
  
  fDphiMassHigh = new TH2F("fDphiMassHigh", "e-h Dphi LS+ULS, mass>0.01",200,0,20,100,-3.14,3.14);
  fOutputList->Add(fDphiMassHigh);
  
  fDphiULSMassLow = new TH2F("fDphiULSMassLow", "e-h Dphi ULS, mass<0.01",200,0,20,100,-3.14,3.14);
  fOutputList->Add(fDphiULSMassLow);
  
  fDphiLSMassLow = new TH2F("fDphiLSMassLow", "e-h Dphi LS, mass<0.01",200,0,20,100,-3.14,3.14);
  fOutputList->Add(fDphiLSMassLow);
  
  fPhotoElecPt = new TH1F("fPhotoElecPt", "photonic electron pt",1000,0,100);
  fOutputList->Add(fPhotoElecPt);
  
  fSemiInclElecPt = new TH1F("fSemiInclElecPt", "Semi-inclusive electron pt",1000,0,100);
  fOutputList->Add(fSemiInclElecPt);
  PostData(1,fOutputList);
}

//________________________________________________________________________
void AliAnalysisTaskElecHadronCorrel::Terminate(Option_t *)
{
  // Info("Terminate");
	AliAnalysisTaskSE::Terminate();
}

//________________________________________________________________________
Bool_t AliAnalysisTaskElecHadronCorrel::ProcessCutStep(Int_t cutStep, AliVParticle *track)
{
  // Check single track cuts for a given cut step
  const Int_t kMCOffset = AliHFEcuts::kNcutStepsMCTrack;
  if(!fCFM->CheckParticleCuts(cutStep + kMCOffset, track)) return kFALSE;
  return kTRUE;
}
//_________________________________________
void AliAnalysisTaskElecHadronCorrel::SelectPhotonicElectron(Int_t itrack, AliESDtrack *track, Bool_t &fFlagPhotonicElec)
{
  //Identify non-heavy flavour electrons using Invariant mass method
  
  fTrackCuts1->SetAcceptKinkDaughters(kFALSE);
  fTrackCuts1->SetRequireTPCRefit(kTRUE);
  fTrackCuts1->SetEtaRange(-0.9,0.9);
  fTrackCuts1->SetRequireSigmaToVertex(kTRUE);
  fTrackCuts1->SetMaxChi2PerClusterTPC(3.5);
  fTrackCuts1->SetMinNClustersTPC(80);
  
  const AliESDVertex *pVtx = fESD->GetPrimaryVertex();
  
  Bool_t flagPhotonicElec = kFALSE;
  
  for(Int_t jTracks = itrack+1; jTracks<fESD->GetNumberOfTracks(); jTracks++){
    AliESDtrack* trackAsso = fESD->GetTrack(jTracks);
    if (!trackAsso) {
      printf("ERROR: Could not receive track %d\n", jTracks);
      continue;
    }
    
    Double_t dEdxAsso = -999., ptAsso=-999., openingAngle = -999.;
    Double_t mass=999., width = -999;
    Bool_t fFlagLS=kFALSE, fFlagULS=kFALSE;
    
    dEdxAsso = trackAsso->GetTPCsignal();
    ptAsso = trackAsso->Pt();
    Int_t chargeAsso = trackAsso->Charge();
    Int_t charge = track->Charge();
    
    if(ptAsso <0.3) continue;
    if(!fTrackCuts1->AcceptTrack(trackAsso)) continue;
    if(dEdxAsso <70 || dEdxAsso>100) continue; //11a pass1
    
    Int_t fPDGe1 = 11; Int_t fPDGe2 = 11;
    if(charge>0) fPDGe1 = -11;
    if(chargeAsso>0) fPDGe2 = -11;
    
    if(charge == chargeAsso) fFlagLS = kTRUE;
    if(charge != chargeAsso) fFlagULS = kTRUE;
    
    AliKFParticle ge1(*track, fPDGe1);
    AliKFParticle ge2(*trackAsso, fPDGe2);
    AliKFParticle recg(ge1, ge2);
    
    if(recg.GetNDF()<1) continue;
    Double_t chi2recg = recg.GetChi2()/recg.GetNDF();
    if(TMath::Sqrt(TMath::Abs(chi2recg))>3.) continue;
    
    AliKFVertex primV(*pVtx);
    primV += recg;
    recg.SetProductionVertex(primV);
    
    recg.SetMassConstraint(0,0.0001);
    
    openingAngle = ge1.GetAngle(ge2);
    if(fFlagLS) fOpeningAngleLS->Fill(openingAngle);
    if(fFlagULS) fOpeningAngleULS->Fill(openingAngle);
    
    if(openingAngle > fOpeningAngleCut) continue;
    
    recg.GetMass(mass,width);
    
    if(fFlagLS) fInvmassLS->Fill(mass);
    if(fFlagULS) fInvmassULS->Fill(mass);
    
    if(mass>fInvmassCut){
      ElectronHadCorrel(itrack,track,fDphiMassHigh);
    }
    if(mass>fInvmassCut){
      if(fFlagULS) ElectronHadCorrel(itrack,track,fDphiULSMassLow);
      if(fFlagLS) ElectronHadCorrel(itrack,track,fDphiLSMassLow);
    }
    
    if(mass<fInvmassCut && fFlagULS && !flagPhotonicElec){
      flagPhotonicElec = kTRUE;
    }
    
  }
  fFlagPhotonicElec = flagPhotonicElec;
  
}
//_________________________________________
void AliAnalysisTaskElecHadronCorrel::ElectronHadCorrel(Int_t itrack, AliESDtrack *track, TH2F *DphiPt)
{
  //Construct Delta Phi between electrons and hadrons
  
  fTrackCuts2->SetAcceptKinkDaughters(kFALSE);
  fTrackCuts2->SetRequireTPCRefit(kTRUE);
  fTrackCuts2->SetRequireITSRefit(kTRUE);
  fTrackCuts2->SetEtaRange(-0.9,0.9);
  fTrackCuts2->SetRequireSigmaToVertex(kTRUE);
  fTrackCuts2->SetMaxChi2PerClusterTPC(3.5);
  fTrackCuts2->SetMinNClustersTPC(80);
  
  for(Int_t ktracks = 0; ktracks<fESD->GetNumberOfTracks(); ktracks++){
    AliESDtrack* trackHad = fESD->GetTrack(ktracks);
    if (!trackHad) {
      printf("ERROR: Could not receive track %d\n", ktracks);
      continue;
    }
    if(ktracks == itrack) continue; //do not select the same electron
    
    Double_t ptHad= -999, pHad=-999., dEdxHad = -999;
    Double_t ptEle = -999;
    Double_t phiEle = -999, phiHad = -999, Dphi = -999;
    Double_t pi = 3.14;
    
    dEdxHad = trackHad->GetTPCsignal();
    ptHad = trackHad->Pt();
    pHad = trackHad->P();
    
    if(ptHad <0.3) continue;
    if(!fTrackCuts2->AcceptTrack(trackHad)) continue;
    
    phiEle = track->Phi();
    phiHad = trackHad->Phi();
    Dphi = phiEle - phiHad;
    if (Dphi > pi)
      Dphi = Dphi - 2*pi;
    if (Dphi < -pi)
      Dphi = Dphi + 2*pi;
    
    ptEle = track->Pt();
    
    DphiPt->Fill(ptEle,Dphi);
  }
}
//_________________________________________
Bool_t AliAnalysisTaskElecHadronCorrel::IsLEDEvent() const
{
 // Identify LED events which had to be discarded

 AliESDCaloCells *cells = fESD->GetEMCALCells();
 Short_t nCells = cells->GetNumberOfCells();
 Int_t nCellCount[2] = {0,0};
 for(Int_t iCell=0; iCell<nCells; iCell++)
   {
     Int_t cellId = cells->GetCellNumber(iCell);
     Double_t cellE = cells->GetCellAmplitude(cellId);
     Int_t sMod = fGeom->GetSuperModuleNumber(cellId);

     if(sMod==3 || sMod==4)
       {
         if(cellE>2)
           nCellCount[sMod-3]++;
       }
   }

 if(nCellCount[0]>7 || nCellCount[1]>7)
   {
     //cout<<"Bad event!"<<endl;
     return kTRUE;
   }
 return kFALSE;
}