/**
 @class PndFtsHoughTracklet

 @author Martin J. Galuska <martin [dot] j [dot] galuska (at) physik [dot] uni (minus) giessen [dot] de>

 @brief Class for saving the result of one Hough transform for FTS PR.

 One object of this class corresponds to one peak in the Hough space or part of a track candidate.
 The tracklet can represent a line or a parabola (actually an arbitrary result of a 2d Hough transform).

 Created: 11.02.2014
*/

#ifndef PNDFTSHOUGHTRACKLET_H
#define PNDFTSHOUGHTRACKLET_H

#include "PndFtsHoughTrackerTask.h"

// Root Class Headers ----------------
#include "PndTrackCand.h"
#include "Rtypes.h"                     // for Double_t, Int_t, etc
#include "FairLogger.h" // for FairLogger, MESSAGE_ORIGIN

// For error reporting
#include "TString.h"
#include <stdexcept>

class PndFtsHit;
class PndTrack;
class TClonesArray;



class PndFtsHoughTracklet : public PndTrackCand {
public:

	// Constructors/Destructors ---------
	PndFtsHoughTracklet(Double_t zRefLabSys=0., PndFtsHoughTrackerTask *trackerTask=0); ///< @brief Set pointer to tracker task (super important as it provides an I/O interface to PandaRoot)
	~PndFtsHoughTracklet();


	// Accessors -----------------------
	void Print() const;

	Bool_t isSet() const { return fIsSet; }; // returns kTRUE iif data from the 2d Hough transforms have been entered

	// add results from Hough transforms
	void SetHoughTransformResults(
			const Double_t thetaVal,
			const Double_t secondVal,
			const Double_t peakHeight,
			const Double_t thetaHw,
			const Double_t secondHw
	);


	// getters for Hough space peak info
	Double_t getPeakHeightFromPeakFinder() const { return fPeakHeightFromPeakFinder; };
	Double_t getThetaRadVal() const { return fThetaRadVal; }; // theta value for peak (in rad)
	Double_t getThetaRadHw() const { return fThetaRadHw; }; // hw = half width = half length of Hough space bin
	Double_t getSecondVal() const { return fSecondVal; }; // second value for peak, see below for explanation

	Double_t getSecondHw() const { return fSecondHw; }; // hw = half width = half length of Hough space bin
	Double_t getZRefLabSys() const { return fZRefLabSys; }; // in cm


	// hits
	UInt_t getNSharedHits(const PndFtsHoughTracklet& rhs); // gives the number of hits that are contained both in rhs and *this







private:
	// Private Data Members ------------
	// for PandaRoot input/output
	PndFtsHoughTrackerTask *fTrackerTask;

	/** @brief For error reporting */
	void throwError(const TString s) const{ throw std::runtime_error(s.Data()); };

	Int_t fVerbose;

	Bool_t fIsSet; // kTRUE if values have already been filled


	Double_t fPeakHeightFromPeakFinder;
	// height of peak in Hough transform
	// (as determined by peakFinder -- does not need to be == fHitId.size()
	// as the peak finder might add a weight to the hits depending on how close they have been to the actual peak)

	// saving peak position in a 2d Hough transform as well as the half width of the histogram
	Double_t fThetaRadVal; // theta angle
	Double_t fThetaRadHw; // error on angle

	Double_t fSecondVal; // second value is x or y intercept for line in zx or zy plane and Q/pZx for parabola in zx plane
	Double_t fSecondHw; // error on second value

	// at which z value in lab sys the values have to be interpreted
	Double_t fZRefLabSys;

	//	void addPeakHits(); // check which hits have contributed to the peak and add them to the hitId vector


	ClassDef(PndFtsHoughTracklet,1);
};

#endif