/**************************************************************************
 * 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.                  *
 **************************************************************************/

/* $Id$ */

//-----------------------------------------------------------------------------
// Class AliMUONHitForRec
// ------------------------
// Hit for reconstruction in ALICE dimuon spectrometer
// Author: J. Gosset
//-----------------------------------------------------------------------------

#include "AliMUONHitForRec.h" 
#include "AliMUONVCluster.h"
#include "AliMUONConstants.h"
#include "AliLog.h"
#include "TMath.h"
#include "Riostream.h"

/// \cond CLASSIMP
ClassImp(AliMUONHitForRec) // Class implementation in ROOT context
/// \endcond

  //__________________________________________________________________________
AliMUONHitForRec::AliMUONHitForRec()
  : TObject(),
    fBendingCoor(0.),
    fNonBendingCoor(0.),
    fZ(0.),
    fBendingReso2(0.),
    fNonBendingReso2(0.),
    fChamberNumber(0),
    fDetElemId(0),
    fHitNumber(0),
    fTTRTrack(0),
    fTrackRefSignal(0),
    fNTrackHits(0)
{
/// Default Constructor
 
}

  //__________________________________________________________________________
AliMUONHitForRec::AliMUONHitForRec(AliMUONVCluster* theRawCluster)
  : TObject(),
    fBendingCoor(theRawCluster->GetY()),
    fNonBendingCoor(theRawCluster->GetX()),
    fZ(0.),
    fBendingReso2(0.),
    fNonBendingReso2(0.),
    fChamberNumber(0),
    fDetElemId(theRawCluster->GetDetElemId()),
    fHitNumber(0),
    fTTRTrack(-1),
    fTrackRefSignal(-1),
    fNTrackHits(0)
{
/// Constructor for AliMUONHitForRec from a raw cluster.
/// Fills the bending and non bending coordinates.

  // other fields will be updated in
  // AliMUONEventReconstructor::AddHitsForRecFromRawClusters,
  return;
}

  //__________________________________________________________________________
AliMUONHitForRec::AliMUONHitForRec (const AliMUONHitForRec& theMUONHitForRec)
  : TObject(theMUONHitForRec),
    fBendingCoor(theMUONHitForRec.fBendingCoor),
    fNonBendingCoor(theMUONHitForRec.fNonBendingCoor),
    fZ(theMUONHitForRec.fZ),
    fBendingReso2(theMUONHitForRec.fBendingReso2),
    fNonBendingReso2(theMUONHitForRec.fNonBendingReso2),
    fChamberNumber(theMUONHitForRec.fChamberNumber),
    fDetElemId(theMUONHitForRec.fDetElemId),
    fHitNumber(theMUONHitForRec.fHitNumber),
    fTTRTrack(theMUONHitForRec.fTTRTrack),
    fTrackRefSignal(theMUONHitForRec.fTrackRefSignal),
    fNTrackHits(theMUONHitForRec.fNTrackHits)
{
/// Copy constructor

}

  //__________________________________________________________________________
AliMUONHitForRec::~AliMUONHitForRec()
{
/// Destructor
}

  //__________________________________________________________________________
AliMUONHitForRec & AliMUONHitForRec::operator=(const AliMUONHitForRec& theMUONHitForRec)
{
/// Assignment operator

  fBendingCoor = theMUONHitForRec.fBendingCoor;
  fNonBendingCoor = theMUONHitForRec.fNonBendingCoor;
  fZ = theMUONHitForRec.fZ;
  fBendingReso2 = theMUONHitForRec.fBendingReso2;
  fNonBendingReso2 = theMUONHitForRec.fNonBendingReso2;
  fChamberNumber = theMUONHitForRec.fChamberNumber;
  fDetElemId = theMUONHitForRec.fDetElemId;
  fHitNumber = theMUONHitForRec.fHitNumber;
  fTTRTrack = theMUONHitForRec.fTTRTrack;
  fTrackRefSignal = theMUONHitForRec.fTrackRefSignal;
  fNTrackHits = theMUONHitForRec.fNTrackHits;
  return *this;
}
  //__________________________________________________________________________
/*AZ
Int_t AliMUONHitForRec::Compare(const TObject* Hit) const
{
  // "Compare" function to sort with increasing chamber number.
  // Returns -1 (0, +1) if ChamberNumber of current HitForRec
  // is smaller than (equal to, larger than) ChamberNumber of Hit
  if (fChamberNumber <  ((AliMUONHitForRec*)Hit)->fChamberNumber) return(-1);
  else if (fChamberNumber == ((AliMUONHitForRec*)Hit)->fChamberNumber) return( 0);
  else return(+1);
}
*/
  //__________________________________________________________________________
Int_t AliMUONHitForRec::Compare(const TObject* Hit) const
{
/// "Compare" function to sort with decreasing Z-coordinate (spectro. MUON z<0).
/// Returns 1 (0, -1) if Z-coordinate of current HitForRec
/// is smaller than (equal to, larger than) Z-coordinate of Hit

  if (fZ <  ((AliMUONHitForRec*)Hit)->fZ) return(1);
  else if (fZ == ((AliMUONHitForRec*)Hit)->fZ) return( 0);
  else return(-1);
}

  //__________________________________________________________________________
Double_t AliMUONHitForRec::NormalizedChi2WithHitForRec(AliMUONHitForRec* hitForRec, Double_t Sigma2Cut) const
{
/// Calculate the normalized Chi2 between the current hitForRec (this) and the hitForRec pointed to by "hitForRec",
/// i.e. the square deviations between the coordinates, in both the bending and the non bending plane,
/// divided by the variance of the same quantities and by "Sigma2Cut".
/// Returns 3 if none of the 2 quantities is OK, something smaller than or equal to 2 otherwise.
/// Would it be more correct to use a real chi square including the non diagonal term ????

  Double_t chi2, chi2Max, diff, normDiff;
  chi2 = 0.0;
  chi2Max = 3.0;
  // coordinate in bending plane
  diff = fBendingCoor - hitForRec->fBendingCoor;
  normDiff = diff * diff / (fBendingReso2 + hitForRec->fBendingReso2) / Sigma2Cut;
  if (normDiff > 1.0) return chi2Max;
  chi2 = chi2 + normDiff;
  // coordinate in non bending plane
  diff = fNonBendingCoor - hitForRec->fNonBendingCoor;
  normDiff = diff * diff / (fNonBendingReso2 + hitForRec->fNonBendingReso2) / Sigma2Cut;
  if (normDiff > 1.0) return chi2Max;
  chi2 = chi2 + normDiff;
  return chi2;
}

//______________________________________________________________________________
void
AliMUONHitForRec::Print(Option_t* /*opt*/) const
{
/// Printing

  cout << "<AliMUONHitForRec> Coordinates (B,NB,Z) = (" 
  << setw(8) << setprecision(5) << fBendingCoor
  << "," << setw(8) << setprecision(5) << fNonBendingCoor << "," 
  << setw(8) << setprecision(5) << fZ << ") "
  << "Reso (B,NB)=(" << setw(8) << setprecision(5) << TMath::Sqrt(fBendingReso2) 
  << "," << setw(8) << setprecision(5) << TMath::Sqrt(fNonBendingReso2)
  << ") " 
  << "Number " << setw(3) << fHitNumber 
  << " within chamber " << setw(3) <<fChamberNumber 
  << " DE " << setw(4) << fDetElemId
  << endl;
}