#ifndef STNTUPLE_TExtrap
#define STNTUPLE_TExtrap

#include "TVector3.h"
class TStnTrack;


class TExtrap {
public:
  TExtrap():rCoil(149.1),rCes(184.15),rCpr(168.29),zCot(150.0),
    zCes(239.6),zPes(185.4),rTof(140.75),zTof(139.7) {}
  ~TExtrap() {}

  Int_t SetParameters(Double_t d0, Double_t phi, Double_t curv, 
		      Double_t z0, Double_t lambda);

  Int_t SetParameters(TStnTrack* track);

  Int_t SetParameters(TVector3* vertex, TVector3* pvec, Int_t charge);

  Double_t PhiAtR(Double_t r);
  Double_t ZAtR(Double_t r);
  Double_t RAtZ(Double_t z);

  TVector3 PositionAtR(Double_t r);
  TVector3 MomentumAtR(Double_t r);

  Bool_t   IsCentral() { return fabs(ZAtROutField(rCes))<zCes;}

  Double_t DetEtaAtShowerMax();

  Int_t    GetCesWedge();
  // if wedge is -1, then find wedge first
  Double_t GetCesLocalX(Int_t wedge = -1);
  Double_t GetCesLocalZ(Int_t wedge = -1);

  Int_t    GetCprWedge();
  // if wedge is -1, then find wedge first
  Double_t GetCprLocalX(Int_t wedge = -1);
  Double_t GetCprLocalZ(Int_t wedge = -1);

  Int_t    GetTofBar();
  Double_t GetTofLocalZ();

  Int_t    GetPhiTower();
  Int_t    GetEtaTower();

private:

  // r at center of wedge
  Int_t    GetWedge(Int_t nWedge, Double_t r);
  Double_t GetLocalX(Int_t wedge, Int_t nWedge, Double_t r);
  Double_t GetLocalZ(Int_t wedge, Int_t nWedge, Double_t r);

  Double_t PhiAtRInField(Double_t r);
  Double_t ZAtRInField(Double_t r);
  Double_t RAtZInField(Double_t z);
  Double_t AlphaAtRInField(Double_t r);

  Double_t PhiAtROutField(Double_t r);
  Double_t ZAtROutField(Double_t r);
  Double_t RAtZOutField(Double_t z);

  // run helix out to coil, find track parameters after that r
  Int_t FillStraight();

  // track parameters
  double d,p,c,z,t;
  // straight section parameters
  double sd,sp,sz,st;

  double rexit,zexit;
  bool outCoil;
  double rCoil,rCes,rCpr,zCot,zCes,zPes,rTof,zTof;

};

#endif