#ifndef TECALBar_hxx_seen
#define TECALBar_hxx_seen

// root
#include <TVector3.h>

// oaEvent
#include <IGeometryId.hxx>
#include <COMETGeomId.hxx>
#include <COMETGeomIdDef.hxx>

//oaGeomInfo
#include <IScintBarGeom.hxx>

namespace COMET
{
	class IECALBar;
};

/// Class for managing the geometry information associated with an ECal
/// scintillator bar.
/// Note that none of the methods are guaranteed to leave the geometry
/// manager untouched. The current node, for example, may change.
class COMET::IECALBar: public COMET::IScintBarGeom
{
	// Note for contributors:
	// This class should work on the assumption that the IECalIdFinder in
	// oaEvent did its job, and all IGeometryId are set properly.
	// Therefore, no usage of geometry paths should be required.
    
    friend class IECALModule;
    
	public:
		/// The ECal bar represented by a GeometryId.
		/// The orientation (0 is X, 1 is Y) is the axis perpendicular
		/// to the lie of the bar.
		/// The number of photosensors that are attached (2, 1, -1)
		/// where the sign determines read-out end in bar's coord system.
  		IECALBar(COMET::IGeometryId geomId, int orientation, int nsensors, int layer_number, int bar_number);
  		
		~IECALBar(){}
		
		/// Returns the full length of the bar.
		double GetLength() const;
		
		/// Returns the number of the bar within it's layer. Indexed from 0.
		int GetBarNumber() const	{	return fBarNumber;	}
		
		/// Returns the layer in which the bar lies. Indexed from 0.
		int GetLayerNumber() const	{	return fLayerNumber;	}
		
		/// Returns a position in the global coordinate system of the
		/// centre of the bar, at the positive end of the bar's length
		/// if orientation = +1, or at the neagative end of the bar's
		/// length if orientation = -1.
		/// Will return a zero vector if orientation is neither +1 nor -1.
		TVector3 GetEnd(const int orientation) const;
		
	private:
		
		/// Layer in which the bar lies.
		/// 0 <= fLayerNumber <= number of layers in the module.
		int fLayerNumber;
		
		/// Number of the bar within it's layer.
		/// 0 <= fBarNumber <= number of bars in the layer.
		int fBarNumber;
};

#endif