// $Id$
// **************************************************************************
// This file is property of and copyright by the ALICE HLT Project          *
// ALICE Experiment at CERN, All rights reserved.                           *
//                                                                          *
// Primary Authors: Sergey Gorbunov <sergey.gorbunov@kip.uni-heidelberg.de> *
//                  Ivan Kisel <kisel@kip.uni-heidelberg.de>                *
//                  for The ALICE HLT Project.                              *
//                                                                          *
// 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.                    *
//                                                                          *
//***************************************************************************


#include "AliHLTTPCCAMCTrack.h"
#include "AliHLTTPCCAMath.h"
#include "TParticle.h"
#include "TDatabasePDG.h"


AliHLTTPCCAMCTrack::AliHLTTPCCAMCTrack()
    : fPDG( 0 ), fP( 0 ), fPt( 0 ), fNHits( 0 ), fNMCPoints( 0 ), fFirstMCPointID( 0 ), fNReconstructed( 0 ), fSet( 0 ), fNTurns( 0 )
{
  //* Default constructor
}


AliHLTTPCCAMCTrack::AliHLTTPCCAMCTrack( const TParticle *part )
    : fPDG( 0 ), fP( 0 ), fPt( 0 ), fNHits( 0 ), fNMCPoints( 0 ), fFirstMCPointID( 0 ), fNReconstructed( 0 ), fSet( 0 ), fNTurns( 0 )
{
  //* Constructor from TParticle

  for ( int i = 0; i < 7; i++ ) fPar[i] = 0;
  for ( int i = 0; i < 7; i++ ) fTPCPar[i] = 0;
  fP = 0;
  fPt = 0;

  if ( !part ) return;
  TLorentzVector mom, vtx;
  part->ProductionVertex( vtx );
  part->Momentum( mom );
  fPar[0] = part->Vx();
  fPar[1] = part->Vy();
  fPar[2] = part->Vz();
  fP = part->P();
  fPt = part->Pt();
  double pi = ( fP > 1.e-4 ) ? 1. / fP : 0;
  fPar[3] = part->Px() * pi;
  fPar[4] = part->Py() * pi;
  fPar[5] = part->Pz() * pi;
  fPar[6] = 0;
  fPDG  = part->GetPdgCode();
  if ( CAMath::Abs( fPDG ) < 100000 ) {
    TParticlePDG *pPDG = TDatabasePDG::Instance()->GetParticle( fPDG );
    if ( pPDG ) fPar[6] = pPDG->Charge() / 3.0 * pi;
  }
}

void AliHLTTPCCAMCTrack::SetTPCPar( float X, float Y, float Z,
                                    float Px, float Py, float Pz )
{
  //* Set parameters at TPC entrance

  for ( int i = 0; i < 7; i++ ) fTPCPar[i] = 0;

  fTPCPar[0] = X;
  fTPCPar[1] = Y;
  fTPCPar[2] = Z;
  double p = CAMath::Sqrt( Px * Px + Py * Py + Pz * Pz );
  double pi = ( p > 1.e-4 ) ? 1. / p : 0;
  fTPCPar[3] = Px * pi;
  fTPCPar[4] = Py * pi;
  fTPCPar[5] = Pz * pi;
  fTPCPar[6] = 0;
  if ( CAMath::Abs( fPDG ) < 100000 ) {
    TParticlePDG *pPDG = TDatabasePDG::Instance()->GetParticle( fPDG );
    if ( pPDG ) fTPCPar[6] = pPDG->Charge() / 3.0 * pi;
  }
}