//
// Class AliRsnCutPIDTPC
//
// General implementation of a single cut strategy, which can be:
// - a value contained in a given interval  [--> IsBetween()   ]
// - a value equal to a given reference     [--> MatchesValue()]
//
// In all cases, the reference value(s) is (are) given as data members
// and each kind of cut requires a given value type (Int, UInt, Double),
// but the cut check procedure is then automatized and chosen thanks to
// an enumeration of the implemented cut types.
// At the end, the user (or any other point which uses this object) has
// to use the method IsSelected() to check if this cut has been passed.
//
// authors: Martin Vala (martin.vala@cern.ch)
//          Alberto Pulvirenti (alberto.pulvirenti@ct.infn.it)
//

#include "AliAnalysisManager.h"
#include "AliESDInputHandler.h"
#include "AliRsnCutPIDTPC.h"

ClassImp(AliRsnCutPIDTPC)

//_________________________________________________________________________________________________
AliRsnCutPIDTPC::AliRsnCutPIDTPC
(const char *name, AliPID::EParticleType type, Double_t min, Double_t max, Bool_t rejectOutside) :
   AliRsnCut(name, AliRsnCut::kDaughter, min, max),
   fInitialized(kFALSE),
   fRejectOutside(rejectOutside),
   fMomMin(0.0),
   fMomMax(1E+20),
   fRefType(type),
   fESDpid(),
   fAODpid()
{
//
// Main constructor.
//
}

//_________________________________________________________________________________________________
AliRsnCutPIDTPC::AliRsnCutPIDTPC
(const AliRsnCutPIDTPC& copy) :
   AliRsnCut(copy),
   fInitialized(kFALSE),
   fRejectOutside(copy.fRejectOutside),
   fMomMin(copy.fMomMin),
   fMomMax(copy.fMomMax),
   fRefType(copy.fRefType),
   fESDpid(copy.fESDpid),
   fAODpid(copy.fAODpid)
{
//
// Copy constructor.
//
}

//_________________________________________________________________________________________________
AliRsnCutPIDTPC& AliRsnCutPIDTPC::operator=(const AliRsnCutPIDTPC& copy)
{
//
// Assignment operator
//

   AliRsnCut::operator=(copy);

   fInitialized   = kFALSE;
   fRejectOutside = copy.fRejectOutside;
   fMomMin        = copy.fMomMin;
   fMomMax        = copy.fMomMax;
   fRefType       = copy.fRefType;
   fESDpid        = copy.fESDpid;
   fAODpid        = copy.fAODpid;

   return (*this);
}

//_________________________________________________________________________________________________
void AliRsnCutPIDTPC::SetBBParam(Double_t p0, Double_t p1, Double_t p2, Double_t p3, Double_t p4)
{
//
// Properly set the Bethe-Bloch parameters in all places where it is needed.
//

   fESDpid.GetTPCResponse().SetBetheBlochParameters(p0, p1, p2, p3, p4);
   fAODpid.GetTPCResponse().SetBetheBlochParameters(p0, p1, p2, p3, p4);
}

//_________________________________________________________________________________________________
Bool_t AliRsnCutPIDTPC::IsSelected(TObject *object)
{
//
// Cut checker.
//

   // initialize if needed
   if (!fInitialized) Initialize();

   // coherence check
   if (!TargetOK(object)) return kFALSE;

   // reject not TPC tracks
   AliVTrack *vtrack = fDaughter->GetRefVtrack();
   if (!vtrack) return kFALSE;
   if (!IsTPC(vtrack)) {
      AliDebug(AliLog::kDebug + 2, "Track is not found in TPC");
      return kFALSE;
   }

   // common evaluation variables
   Double_t     mom;
   AliESDtrack *esdTrack = fDaughter->GetRefESDtrack();
   AliAODTrack *aodTrack = fDaughter->GetRefAODtrack();

   // get inner momentum, needed for BB computation
   if (esdTrack)
      mom = esdTrack->GetInnerParam()->P();
   else if (aodTrack)
      mom = aodTrack->GetDetPid()->GetTPCmomentum();
   else {
      AliDebug(AliLog::kDebug + 2, Form("Impossible to process an object of type '%s'. Cut applicable only to ESD/AOD tracks", fDaughter->GetRef()->ClassName()));
      return kFALSE;
   }

   // assign PID nsigmas to default cut check value
   // since bad object types are rejected before, here we have an ESD track or AOD track
   if (esdTrack)
      fCutValueD = fESDpid.GetTPCResponse().GetNumberOfSigmas(mom, esdTrack->GetTPCsignal(), esdTrack->GetTPCsignalN(), fRefType);
   else
      fCutValueD = fAODpid.NumberOfSigmasTPC(aodTrack, fRefType);

   // use AliRsnCut default method to check cut
   Bool_t cutCheck = OkRangeD();

   // now check the momentum:
   // -- if it stays inside the accepted range, track just checked
   //    with respect to the nsigma band
   // -- if it stays outside the accepted range and 'fRejectOutside' is kTRUE,
   //    track is always rejected, while if 'fRejectOutside' is kFALSE,
   //    track is accepted if it stays inside the nsigma band
   if ((mom >= fMomMin && mom <= fMomMax))
      return cutCheck;
   else {
      AliDebug(AliLog::kDebug + 2, Form("Track momentum = %.5f, outside allowed range", mom));
      return ((!fRejectOutside) && cutCheck);
   }
}

//_________________________________________________________________________________________________
void AliRsnCutPIDTPC::Print(const Option_t *) const
{
//
// Print information on this cut
//

   AliInfo(Form("Cut name                    : %s", GetName()));
   AliInfo(Form("--> cut range (nsigma)      : %.3f %.3f", fMinD, fMaxD));
   AliInfo(Form("--> momentum range          : %.3f %.3f", fMomMin, fMomMax));
   AliInfo(Form("--> tracks outside range are: %s", (fRejectOutside ? "rejected" : "accepted")));
}

//_________________________________________________________________________________________________
void AliRsnCutPIDTPC::Initialize()
{
//
// Initialize ESD pid object from global one
//

   AliAnalysisManager *mgr = AliAnalysisManager::GetAnalysisManager();
   AliESDInputHandler *handler = dynamic_cast<AliESDInputHandler*>(mgr->GetInputEventHandler());
   if (handler) {
      AliESDpid *pid = handler->GetESDpid();
      if (pid) fESDpid = (*pid);
   }

   fInitialized = kTRUE;
}