///////////////////////////////////////////////////////////////////////////////
/// \class RAT::Detector
///
/// \brief  Constructs the detector
///
/// \author Phil G Jones <p.g.jones@qmul.ac.uk>
/// \author Aksel Hallin <aksel.hallin@ualberta.ca> -- contact person
///
/// REVISION HISTORY:\n
/// 	2013-06-20 : P G Jones - New file, code from DetectorConstructor \n
///
/// \details Constructs the detector for Geant4, materials, optics, surfaces
/// and geometry.
///
///////////////////////////////////////////////////////////////////////////////

#ifndef __RAT_Detector_hh__
#define __RAT_Detector_hh__

#include <G4VUserDetectorConstruction.hh>

#include <vector>

class G4String;
class G4LogicalVolume;
class G4PhysicalVolume;

namespace RAT
{
class DetectorMessenger;

class Detector : public G4VUserDetectorConstruction
{
public:
  /// Find the logical volume by name
  ///
  /// @param[in] volume the name of the volume to find.
  /// @return the logical volume if found, NULL if not
  static G4LogicalVolume* FindLogicalVolume( const G4String& volume );

  /// Find the physical volume by name
  ///
  /// @param[in] volume the name of the volume to find.
  /// @param[in] check FIXME add comment here
  /// @return the physical volume if found, NULL if not
  static G4VPhysicalVolume* FindPhysicalVolume( const G4String& volume,
                                                const bool check=true );

  /// Return the world volume
  ///
  /// There can only be one world volume, that returned by this
  ///
  /// @return the physical world volume
  static G4VPhysicalVolume* GetWorld() { return FindPhysicalVolume( "world" ); }

  /// Return the active volume(s)
  ///
  /// The active volume(s) are those that contain 0, 0, 0 i.e. the origin
  /// Note that this volume could be a split volume, hence the plural return.
  ///
  /// @return a vector of physical volumes that are active
  static std::vector<G4VPhysicalVolume*> GetActiveVolumes();

  /// Return the number of electrons in the active volumes
  ///
  /// Helper function to return the number of electrons in the active volume(s).
  ///
  /// @return a vector of electron numbers, ordering matches GetActiveVolumes
  static std::vector<double> GetActiveElectrons();


  /// Construct the Detector, do nothing
  Detector();

  /// Destruct and delete the existing geometry
  virtual ~Detector();

  /// Construct the detector
  ///
  /// @return the world physical volume
  G4VPhysicalVolume* Construct();

  /// Set the check overlaps flag
  ///
  /// @param[in] check value, true or false
  void SetCheckOverlaps( const bool check ) { fCheckOverlaps = check; }
private:
  /// Clean (delete) the existing geometry
  void CleanGeometry();

  DetectorMessenger* fMessenger; ///< The detector messenger
  bool fCheckOverlaps; ///< If true overlap checking is enabled
};

} //::RAT

#endif