#include <iostream>
#include "TMath.h"
#include "TString.h"

using namespace std;

// macro to implement the e-veto cut-based elections
/*
 * returns false if it a tau
 *         true  if it is an electron candidate
 *
 * input D3PD variables: ******************************************************
 * eta       : tau_seedCalo_track_eta (track with highest tau_seedCalo_track_pt)
 * Et        : tau_seedCalo_etEMAtEMScale   (not explicitly used)
 * TrkAvgDist: tau_seedCalo_trkAvgDist
 * HoP       : tau_seedCalo_etHadAtEMScale/tau_leadTrkPt
 * EoP       : tau_seedCalo_etEMAtEMScale/tau_leadTrkPt
 * TrtRatio  : tau_calcVars_TRTHTOverLT_LeadTrk
 * ****************************************************************************
 * Usage:
 * tauElectronVeto(float eta, float Et, float Estripmax, float HoP,
 *                 float EoP, float TrtRatio, TString qual)
 * qual: loose, medium, tight or tighter
 * returns true if the object is identified as an electron by the algorithm
 * ATLAS tauWG supported points: loose, medium and tight, tighter is for test
 * purposes
 *
 * Changes since the last release (12 May 2011)
 *
 * eta range changed: central taus were defined 0.0-1.7 now 0.0-2.0
 * variables replaced: 
 * OLD VARIABLE (ATHENA REL16)          -> NEW VARIABLE (ATHENA REL17)
 * tau_seedTrk_secMaxStripEt            -> tau_seedCalo_trkAvgDist
 * tau_seedTrk_hadLeakEt                -> tau_seedCalo_etHadAtEMScale/tau_leadTrkPt
 * tau_seedTrk_sumEMCellEtOverLeadTrkPt -> tau_seedCalo_etEMAtEMScale/tau_leadTrkPt
 * ****************************************************************************
 * nikolaos.rompotis at cern.ch - 6 Oct 2011
 *
 */

bool tauElectronVetoRel17(float eta, float Et, float TrkAvgDist, float HoP,
			  float EoP, float TrtRatio, TString qual) {

  float TrkAvgDist_C0, HoP_C0, EoP_C0, TrtRatio_C0a, TrtRatio_C0b, TrtRatio_C0c;
  float HoP_C1, EoP_C1;

  // define the cut values .............
  if (qual == "loose") {
    TrkAvgDist_C0= 0.028;
    HoP_C0       = 0.050;
    EoP_C0       = 0.927;
    TrtRatio_C0a = 0.216;
    TrtRatio_C0b = 0.104;
    TrtRatio_C0c = 0.102;
      		          
    HoP_C1       = 0.085;
    EoP_C1       = 0.112;
  }
  else if (qual == "medium") {
    TrkAvgDist_C0= 0.046;
    HoP_C0       = 0.081;
    EoP_C0       = 0.832;
    TrtRatio_C0a = 0.179;
    TrtRatio_C0b = 0.073;
    TrtRatio_C0c = 0.125;
            	   	       
    HoP_C1       = 0.218;
    EoP_C1       = 1.386;
  }
  else if (qual == "tight") {
    TrkAvgDist_C0= 0.026;
    HoP_C0       = 0.472;
    EoP_C0       = 3.059;
    TrtRatio_C0a = 0.161;
    TrtRatio_C0b = 0.097;
    TrtRatio_C0c = 0.092;
            	   	   
    HoP_C1       = 0.304;
    EoP_C1       = 0.990;

  }
  else if (qual == "tighter") {
    TrkAvgDist_C0= 0.097;
    HoP_C0       = 0.112;
    EoP_C0       = 0.104;
    TrtRatio_C0a = 0.101;
    TrtRatio_C0b = 0.592;
    TrtRatio_C0c = 0.057;
             	   	   
    HoP_C1       = 0.305;
    EoP_C1       = 0.992;
  }
  else {
    std::cout << "No such option for qual=" << qual << endl;
    return false;
  }
  
  if (qual == "medium") {
    if (tauElectronVetoRel17(eta, Et, TrkAvgDist, HoP, EoP, TrtRatio, "loose"))
      return true;
  }
  else if (qual == "tight") {
    if (tauElectronVetoRel17(eta, Et, TrkAvgDist, HoP, EoP, TrtRatio, "medium"))
      return true;
  }
  else if (qual == "tighter") { // tighter is defined also wrt to the medium
    if (tauElectronVetoRel17(eta, Et, TrkAvgDist, HoP, EoP, TrtRatio, "medium"))
      return true;
  }
  
  // ...................................
  if ( fabs(eta) < 2.0 ) {  // central taus
    //
    if (HoP > HoP_C0) { 
      if ( TrtRatio <= TrtRatio_C0a) return false;
      else return true;
    }
    else {
      if (TrkAvgDist > TrkAvgDist_C0) {
	if (TrtRatio <= TrtRatio_C0b) return false;
	else return true;
      }
      else {
	if (TrtRatio <= TrtRatio_C0c && EoP <= EoP_C0) return false;
	else return true;
      }
    }
  }
  else {                     // forward taus
    if (HoP > HoP_C1) return false;
    else {
      if (EoP <= EoP_C1) return false;
      else return true;
    }
  }
}