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// $Id: F04SteppingAction.cc 73014 2013-08-15 08:54:47Z gcosmo $
//
/// \file field/field04/src/F04SteppingAction.cc
/// \brief Implementation of the F04SteppingAction class
//

#include "G4Track.hh"

#include "F04SteppingAction.hh"
#include "G4SteppingManager.hh"
#include "F04SteppingActionMessenger.hh"

#include "G4ParticleTypes.hh"
#include "G4LogicalVolumeStore.hh"

#include "F04UserTrackInformation.hh"

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

F04SteppingAction::F04SteppingAction()
 : G4UserSteppingAction(),
   fSteppingMessenger(0),
   fTargetVolume(0),
   fTestPlaneVolume(0)
{
  fSteppingMessenger = new F04SteppingActionMessenger();
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

F04SteppingAction::~F04SteppingAction()
{
  delete fSteppingMessenger ;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......

void F04SteppingAction::UserSteppingAction(const G4Step* theStep)
{
  G4Track* theTrack = theStep->GetTrack();
  
  // Get pointers to test volumes (only once)
  if ( ! fTargetVolume ) {
    fTargetVolume
      = G4LogicalVolumeStore::GetInstance()->GetVolume("Target");
    fTestPlaneVolume
     = G4LogicalVolumeStore::GetInstance()->GetVolume("TestPlane");
  }   
 
  if (theTrack->GetParentID()==0) {
    //This is a primary track
    G4LogicalVolume* theVolume 
      = theStep->GetPreStepPoint()->GetPhysicalVolume()->GetLogicalVolume();
    if (theVolume != fTargetVolume) {
       theTrack->SetTrackStatus(fStopAndKill);
       return;
    }
  }

//  G4ParticleDefinition* particleType = theTrack->GetDefinition();

  // check if it is entering the test volume
  G4StepPoint* thePrePoint = theStep->GetPreStepPoint();
  G4VPhysicalVolume* thePrePV = thePrePoint->GetPhysicalVolume();
  G4LogicalVolume* thePreLV = thePrePV->GetLogicalVolume();

  G4LogicalVolume* thePostLV = 0;
  G4StepPoint* thePostPoint = theStep->GetPostStepPoint();

  if (thePostPoint) {
     G4VPhysicalVolume* thePostPV = thePostPoint->GetPhysicalVolume();
     if (thePostPV) thePostLV = thePostPV->GetLogicalVolume();
  }

  if (thePostLV == fTestPlaneVolume &&
      thePreLV  != fTestPlaneVolume) {

//     G4double x = theTrack->GetPosition().x();
//     G4double y = theTrack->GetPosition().y();

     G4ThreeVector theMomentumDirection = theTrack->
                          GetDynamicParticle()->GetMomentumDirection();
//     G4double theTotalMomentum = theTrack->GetDynamicParticle()->
//                                                    GetTotalMomentum();

     // then kill the track
     theTrack->SetTrackStatus(fStopAndKill);
     return;

  }

//  G4double z = theTrack->GetPosition().z();

  F04UserTrackInformation* trackInformation =
                      (F04UserTrackInformation*)theTrack->GetUserInformation();

  if (trackInformation->GetTrackStatusFlag() != reverse) {
     if (thePreLV  != fTargetVolume ) {
        if ( theTrack->      GetMomentumDirection().z()>0.0 &&
             theTrack->GetVertexMomentumDirection().z()<0.0     )
        {
             trackInformation->SetTrackStatusFlag(reverse);
        }
     }
  }

  // check if it is alive
  if (theTrack->GetTrackStatus() == fAlive) { return; }

  if (thePostPoint->GetProcessDefinedStep() != 0) {
     if (thePostPoint->GetProcessDefinedStep()->GetProcessName() != "Decay")
                                                                       return;
  }

}
