#include <G4VUserDetectorConstruction.hh>
#include <G4tgbVolumeMgr.hh>

class Detector : public G4VUserDetectorConstruction
{
	private:
		G4String fInput;

	public:
		Detector(const char* file="geom.tg")
			: G4VUserDetectorConstruction(), fInput(file) {};

		G4VPhysicalVolume* Construct() {
			G4tgbVolumeMgr::GetInstance()->AddTextFile(fInput);
			return G4tgbVolumeMgr::GetInstance()->ReadAndConstructDetector();
		}
};

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#include <G4Run.hh>
#include <G4UserRunAction.hh>
#include <G4GenericAnalysisManager.hh>
// choose analysis technology according to file extension
using G4AnalysisManager = G4GenericAnalysisManager;

class RunAction : public G4UserRunAction
{
	public:
		RunAction() : G4UserRunAction() { G4AnalysisManager::Instance(); }
		~RunAction() { delete G4AnalysisManager::Instance(); }

		void BeginOfRunAction(const G4Run*)
		{ G4AnalysisManager::Instance()->OpenFile(); }
		void EndOfRunAction(const G4Run*) {
			G4AnalysisManager::Instance()->Write();
			G4AnalysisManager::Instance()->CloseFile();
		}
};

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#include <G4VUserPrimaryGeneratorAction.hh>
#include <G4GeneralParticleSource.hh>
/**
 * Call Geant4 General Particle Source to generate particles.
 */
class Generator : public G4VUserPrimaryGeneratorAction
{
	private:
		G4GeneralParticleSource* fSource;
	public:
		Generator() : G4VUserPrimaryGeneratorAction(), fSource(0) {
			fSource = new G4GeneralParticleSource; }
		virtual ~Generator() { delete fSource; }
		virtual void GeneratePrimaries(G4Event* evt)
		{ fSource->GeneratePrimaryVertex(evt); } ///< add sources to an event
};

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#include <G4TScoreHistFiller.hh>
#include "G4VUserActionInitialization.hh"

class Action : public G4VUserActionInitialization
{
	public:
    G4TScoreHistFiller<G4AnalysisManager>* filler;
		Action() : G4VUserActionInitialization() { 
			filler = new G4TScoreHistFiller<G4AnalysisManager>; }
		~Action() { delete filler; }
		void BuildForMaster() const { SetUserAction(new RunAction); }
		void Build() const {
			SetUserAction(new RunAction);
			SetUserAction(new Generator);
		} 
};

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
#include <G4RunManagerFactory.hh>
#include <G4PhysListFactory.hh>
#include <G4GeometryManager.hh>
#include <G4ScoringManager.hh>
#include <G4VisExecutive.hh>
#include <G4UIExecutive.hh>
#include <G4UImanager.hh>

int main(int argc, char** argv)
{
	// https://gitlab.cern.ch/geant4/geant4/-/tree/master/source/tasking
	auto *run = G4RunManagerFactory::CreateRunManager();
	G4ScoringManager::GetScoringManager(); // activate macro commands for scoring

	G4PhysListFactory physics;
	run->SetUserInitialization(physics.ReferencePhysList());

	Detector* detector;
	if (argc>1) detector = new Detector(argv[1]);
	else detector = new Detector();
	run->SetUserInitialization(detector);

	run->SetUserInitialization(new Action);

	G4VisManager* vis = new G4VisExecutive("quiet");
	vis->Initialize();

	if (argc<3) { // interactive mode
		G4UIExecutive ui(argc, argv);
		ui.SessionStart();
	} else {      // batch mode
		G4String cmd = "/control/execute ";
		G4UImanager::GetUIpointer()->ApplyCommand(cmd+argv[2]);
	}

	delete vis;

//	G4GeometryManager::GetInstance()->OpenGeometry();
}