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// Author: Christian Velten (2025)

#ifndef G4MOLECULELOCATOR_HH
#define G4MOLECULELOCATOR_HH 1
#pragma once

#include "G4TouchableHandle.hh"
#include "G4ThreadLocalSingleton.hh"

#include <memory>

class G4Track;
class G4ITNavigator;

class G4MoleculeLocator final
{
  friend class G4ThreadLocalSingleton<G4MoleculeLocator>;
  public:
    static G4MoleculeLocator* Instance();

    ~G4MoleculeLocator() = default;

  private:
    G4MoleculeLocator();
    G4MoleculeLocator(const G4MoleculeLocator&) = delete;
    G4MoleculeLocator(G4MoleculeLocator&&) = delete;
    G4MoleculeLocator& operator=(const G4MoleculeLocator&) = delete;
    G4MoleculeLocator& operator=(G4MoleculeLocator&&) = delete;

    G4ThreadLocalStatic G4MoleculeLocator* fpInstance;

    G4bool fIsInitialized{false};
    std::unique_ptr<G4ITNavigator> fNavigator;

    void Initialize();

  public:
    void LocateMoleculeSetStateAndTouchable(G4Track*);
    G4TouchableHandle LocateMoleculeTrack(const G4Track*);
};

#endif