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//
#include "LXeSteppingAction.hh"
#include "LXeEventAction.hh"
#include "LXeTrackingAction.hh"
#include "LXeTrajectory.hh"
#include "LXePMTSD.hh"
#include "LXeUserTrackInformation.hh"
#include "LXeUserEventInformation.hh"
#include "LXeSteppingMessenger.hh"
#include "RecorderBase.hh"

#include "G4SteppingManager.hh"
#include "G4SDManager.hh"
#include "G4EventManager.hh"
#include "G4ProcessManager.hh"
#include "G4Track.hh"
#include "G4Step.hh"
#include "G4Event.hh"
#include "G4StepPoint.hh"
#include "G4TrackStatus.hh"
#include "G4VPhysicalVolume.hh"
#include "G4ParticleDefinition.hh"
#include "G4ParticleTypes.hh"
#include "G4OpBoundaryProcess.hh"

//_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
LXeSteppingAction::LXeSteppingAction(RecorderBase* r)
  :recorder(r),oneStepPrimaries(false)
{
  steppingMessenger = new LXeSteppingMessenger(this);
}

//_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
LXeSteppingAction::~LXeSteppingAction()
{}

//_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_-_
void LXeSteppingAction::UserSteppingAction(const G4Step * theStep){
  G4Track* theTrack = theStep->GetTrack();
  
  LXeUserTrackInformation* trackInformation
    =(LXeUserTrackInformation*)theTrack->GetUserInformation();
  LXeUserEventInformation* eventInformation
    =(LXeUserEventInformation*)G4EventManager::GetEventManager()
    ->GetConstCurrentEvent()->GetUserInformation();

  G4StepPoint* thePrePoint = theStep->GetPreStepPoint();
  G4VPhysicalVolume* thePrePV = thePrePoint->GetPhysicalVolume();

  G4StepPoint* thePostPoint = theStep->GetPostStepPoint();
  G4VPhysicalVolume* thePostPV = thePostPoint->GetPhysicalVolume();

  G4OpBoundaryProcessStatus boundaryStatus=Undefined;
  static G4OpBoundaryProcess* boundary=NULL;
  
  //find the boundary process only once
  if(!boundary){
    G4ProcessManager* pm 
      = theStep->GetTrack()->GetDefinition()->GetProcessManager();
    G4int nprocesses = pm->GetProcessListLength();
    G4ProcessVector* pv = pm->GetProcessList();
    G4int i;
    for( i=0;i<nprocesses;i++){
      if((*pv)[i]->GetProcessName()=="OpBoundary"){
	boundary = (G4OpBoundaryProcess*)(*pv)[i];
	break;
      }
    }
  }

  if(theTrack->GetParentID()==0){
    //This is a primary track
    
    G4TrackVector* fSecondary=fpSteppingManager->GetfSecondary();   
    G4int tN2ndariesTot = fpSteppingManager->GetfN2ndariesAtRestDoIt()
      + fpSteppingManager->GetfN2ndariesAlongStepDoIt()
      + fpSteppingManager->GetfN2ndariesPostStepDoIt();
    
    //If we havent already found the conversion position and there were 
    //secondaries generated, then search for it
    if(!eventInformation->IsConvPosSet() && tN2ndariesTot>0 ){    
      for(size_t lp1=(*fSecondary).size()-tN2ndariesTot; 
	  lp1<(*fSecondary).size(); lp1++){
	const G4VProcess* creator=(*fSecondary)[lp1]->GetCreatorProcess();
	if(creator){
	  G4String creatorName=creator->GetProcessName();
	  if(creatorName=="phot"||creatorName=="compt"||creatorName=="conv"){ 
	    //since this is happening before the secondary is being tracked
	    //the Vertex position has not been set yet(set in initial step)
	    eventInformation->SetConvPos((*fSecondary)[lp1]->GetPosition());
	  } 
	}
      }
    }

    if(oneStepPrimaries&&thePrePV->GetName()=="scintillator")
      theTrack->SetTrackStatus(fStopAndKill);
  }

  if(!thePostPV){//out of world
    return;
  }

  G4ParticleDefinition* particleType = theTrack->GetDefinition();
  if(particleType==G4OpticalPhoton::OpticalPhotonDefinition()){
    //Optical photon only

    if(thePrePV->GetName()=="Slab")
      //force drawing of photons in WLS slab
      trackInformation->SetForceDrawTrajectory(true);
    else if(thePostPV->GetName()=="expHall")
      //Kill photons entering expHall from something other than Slab
      theTrack->SetTrackStatus(fStopAndKill);
        
    //Was the photon absorbed by the absorption process
    if(thePostPoint->GetProcessDefinedStep()->GetProcessName()
       =="OpAbsorption"){
      eventInformation->IncAbsorption();
      trackInformation->AddTrackStatusFlag(absorbed);
    }
   
    boundaryStatus=boundary->GetStatus();
 
    //Check to see if the partcile was actually at a boundary
    //Otherwise the boundary status may not be valid
    //Prior to Geant4.6.0-p1 this would not have been enough to check
    if(thePostPoint->GetStepStatus()==fGeomBoundary){
      switch(boundaryStatus){
      case Absorption:
	trackInformation->AddTrackStatusFlag(boundaryAbsorbed);
	eventInformation->IncBoundaryAbsorption();
	break;
      case Detection: //Note, this assumes that the volume causing detection
                      //is the photocathode because it is the only one with
	              //non-zero efficiency
	{
	  //Triger sensitive detector manually since photon is
	  //absorbed but status was Detection
	  G4SDManager* SDman = G4SDManager::GetSDMpointer();
	  G4String sdName="/LXeDet/pmtSD";
	  LXePMTSD* pmtSD = (LXePMTSD*)SDman
	    ->FindSensitiveDetector(sdName);
	  if(pmtSD)
	    pmtSD->ProcessHits_constStep(theStep,NULL);
	  trackInformation->AddTrackStatusFlag(hitPMT);
	  break;
	}
      case FresnelReflection:
      case TotalInternalReflection:
      case SpikeReflection:
	trackInformation->IncReflections();
	break;
      default:
	break;
      }
      if(thePostPV->GetName()=="sphere")
	trackInformation->AddTrackStatusFlag(hitSphere);
    }
  }
  
  if(recorder)recorder->RecordStep(theStep);
}