#ifndef TGeomInfo_hxx_seen
#define TGeomInfo_hxx_seen

#include <TVector3.h>

//#include <oaEvent_version.h>
#include <IOADatabase.hxx>
#include <IGeometryId.hxx>

#include <IDetectorSolenoidGeom.hxx>
#include <IStrawTrkGeom.hxx>
#include <IECALGeom.hxx>

/// Namespace surrounding all COMET code.
namespace COMET {
    class IGeomInfo;
    class ICDCGeom;
    class ICTHGeom;
    class IHit;
}

/// A singleton class that creates, and provides access too, instances of
/// separate, 'singleton like' classes containing utility functions specific
/// to each sub-detector.
class COMET::IGeomInfo {
public:

  virtual ~IGeomInfo();

  /// Get a reference to the singleton instance of geometry information.
  static IGeomInfo& Get(void);

  /// Get a reference to the singleton instance of CDC geometry information.
  static const ICDCGeom& CDC();

  /// Get a reference to the singleton instance of CTH geometry information.
  static const ICTHGeom& CTH();

  /// Get a reference to the singleton instance of Detector Solenoid geometry information.
  static IDetectorSolenoidGeom& DetectorSolenoid();

  /// Get a reference to the singleton instance of StrawTrk geometry information.
  static IStrawTrkGeom& StrawTrk();

  /// Get a reference to the singleton instance of ECAL geometry information.
  static IECALGeom& ECAL();


  /// Translate an xyz position into a global node id.  This takes a
  /// position in the global coordinate system and returns the associated
  /// geometry identifier.  If the position is not associated with an
  /// identifier, then this returns an empty identifier.  Code using the
  /// method should ensure that the returned identifier is a real volume.
  /// For instance:
  ///
  /// \code
  /// IGeometryId id = COMET::IGeomInfo::Get().GeomId(x,y,z);
  /// if (id == COMET::IGeometryId()) {
  ///     std::cout << "x,y,z is not in a detector volume"
  ///               << std::endl;
  /// }
  /// \endcode
  COMET::IGeometryId GeomId(double x, double y, double z);

  /// {@ Translate a node ID into an extent in the master coordinate system.
  /// The node extent is defined as the "half-length" of the dimension.  For
  /// instance, a box which is 2cmx2cmx10cm will have an extend of (1cm,
  /// 1cm, 5cm).  This is how far the object extends from its reference
  /// point.
  TVector3 NodeExtent(COMET::IGeometryId geomId);
  TVector3 NodeExtent(const COMET::IHit& hit);
  // @}

  /// Fine the bounding box for the node in the local coordinate system.
  /// The bounding box is defined as the "half-length" of the dimension.
  /// For instance a box which is 2cmx2cmx10cm will have an extend of (1cm,
  /// 1cm, 5cm).  This is how far the object extends from its center.
  TVector3 NodeSize(COMET::IGeometryId geomId);

  /// Translate a node id into a geometry path name.
  std::string NodeName(COMET::IGeometryId geomId);

  /// Translate a node id into a position in the master coordinate system.
  /// If the input geometry identifier does not correspond to a volume, this
  /// returns an unspecified position.
  TVector3 NodePosition(COMET::IGeometryId geomId);

  /// Translate a position in the master coordinate system to a position in
  /// the local coordinate system of the geometry id.
  TVector3 MasterToLocal(COMET::IGeometryId geomId, double x, double y, double z);

  /// Translate a vector in the master coordinate system to a vector in
  /// the local coordinate system of the geometry id.
  TVector3 MasterToLocalVect(COMET::IGeometryId geomId, double x, double y, double z);

  /// Translate a position in the local coordinate system of a geometry id
  /// into a position in the master coordinate system.
  TVector3 LocalToMaster(COMET::IGeometryId geomId, double x, double y, double z);

  /// Translate a vector in the local coordinate system of a geometry id
  /// into a vector in the master coordinate system.
  TVector3 LocalToMasterVect(COMET::IGeometryId geomId, double x, double y, double z);

  /// Optioned Get radiation length ...
  /// Methods:
  ///   - 0: use (corrected) root version
  ///   - 1: use PDG method
  ///   - 2: use simplified PDG method
  double X0(TGeoMaterial * mat, int method = 0);

  /// An internal COMET::IGeomInfo class used to update tables when the
  /// geometry gets changed.
  class IGeometryChange : public COMET::IOADatabase::IGeometryChange {
  public:
    /// The callback to build the internal tables.
    void Callback(const COMET::ICOMETEvent* const event);
  };
  friend class COMET::IGeomInfo::IGeometryChange;
private:

  IGeomInfo();

  /// Private copy c'tor, no imp.
  IGeomInfo(const IGeomInfo& src);

  /// Private copy asg't operator, no imp.
  IGeomInfo& operator=(const IGeomInfo& rhs);

  /// Fill the internal tables.
  void FillInformation(void);

  /// Clear the internal tables.
  void Clear(void);

  /// The static pointer to the singleton instance.
  static IGeomInfo* fGeomInfo;

  /// The geometry manager that is currently described in this class.  This
  /// should not be used in regular code.  Use gGeoManager instead.
  TGeoManager* fGeoManager;

  /// Get Geometry description of CDC.
  ICDCGeom* fCDCGeom;

  /// Get Geometry description of CTH.
  ICTHGeom* fCTHGeom;

  /// Get Geometry description of DetectorSolenoid.
  IDetectorSolenoidGeom* fDetectorSolenoidGeom;

  /// Get Geometry description of StrawTrk.
  IStrawTrkGeom* fStrawTrkGeom;

  /// Get Geometry description of ECAL.
  IECALGeom* fECALGeom;
};
#endif