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/// \file GB06BOptrSplitAndKillByImportance.cc
/// \brief Implementation of the GB06BOptrSplitAndKillByImportance class

#include "GB06BOptrSplitAndKillByImportance.hh"

#include "GB06BOptnSplitAndKillByImportance.hh"

#include "G4BiasingProcessInterface.hh"
#include "G4BiasingProcessSharedData.hh"
#include "G4ParallelGeometriesLimiterProcess.hh"
#include "G4ParticleDefinition.hh"
#include "G4ParticleTable.hh"
#include "G4TouchableHandle.hh"
#include "G4TransportationManager.hh"
#include "G4VProcess.hh"

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

GB06BOptrSplitAndKillByImportance::GB06BOptrSplitAndKillByImportance(G4String particleName,
                                                                     G4String name)
  : G4VBiasingOperator(name),
    fParallelWorld(nullptr),
    fParallelWorldIndex(-1),
    fBiasingLimiterProcess(nullptr)
{
  fParticleToBias = G4ParticleTable::GetParticleTable()->FindParticle(particleName);

  if (fParticleToBias == nullptr) {
    G4ExceptionDescription ed;
    ed << "Particle `" << particleName << "' not found !" << G4endl;
    G4Exception("GB06BOptrSplitAndKillByImportance(...)", "exGB06.01", JustWarning, ed);
  }

  fSplitAndKillByImportance = new GB06BOptnSplitAndKillByImportance("splitterFor_" + particleName);
}

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

GB06BOptrSplitAndKillByImportance::~GB06BOptrSplitAndKillByImportance()
{
  delete fSplitAndKillByImportance;
}

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

void GB06BOptrSplitAndKillByImportance::StartRun()
{
  // ---------------
  // -- Setup stage:
  // ---------------
  // -- get the particle process manager...
  const G4ProcessManager* processManager = fParticleToBias->GetProcessManager();
  // -- ... to obtain the biasing information shared among this particle processes:
  fBiasingSharedData = G4BiasingProcessInterface::GetSharedData(processManager);
  // if biasing off, the pointer is nullptr
  if (fBiasingSharedData == nullptr) return;
  // -- Remember the index of the parallel world:
  fBiasingLimiterProcess = fBiasingSharedData->GetParallelGeometriesLimiterProcess();
  fParallelWorldIndex = fBiasingLimiterProcess->GetParallelWorldIndex(fParallelWorld);

  // -- Setup the biasing operation:
  fSplitAndKillByImportance->SetBiasingSharedData(fBiasingSharedData);
  fSplitAndKillByImportance->SetParallelWorldIndex(fParallelWorldIndex);
  fSplitAndKillByImportance->SetImportanceMap(&fImportanceMap);
}

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

G4VBiasingOperation* GB06BOptrSplitAndKillByImportance::ProposeNonPhysicsBiasingOperation(
  const G4Track* track, const G4BiasingProcessInterface* /*callingProcess*/)
{
  // -- Check if current particle type is the one to bias:
  if (track->GetDefinition() != fParticleToBias) return nullptr;

  // -- if so, request biasing:
  return fSplitAndKillByImportance;
}
