#ifndef ALITPCSPACECHARGE_H
#define ALITPCSPACECHARGE_H

/* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 * See cxx source for full Copyright notice                               */

////////////////////////////////////////////////////////////////////////////
// AliTPCSpaceCharge class                                                //
// Authors: Jim Thomas, Stefan Rossegger                                  //
////////////////////////////////////////////////////////////////////////////

#include "AliTPCCorrection.h"


class TH2; 

class AliTPCSpaceCharge : public AliTPCCorrection {
public:
  AliTPCSpaceCharge();
  virtual ~AliTPCSpaceCharge();

  // initialization and update functions
  virtual void Init();
  virtual void Update(const TTimeStamp &timeStamp);
  void    SetInputSpaceCharge(TH2 * hisSpaceCharge){fSpaceChargeHistogram = hisSpaceCharge;}  // MI add
  const TH2 *   GetInputSpaceCharge(){return fSpaceChargeHistogram;}       // MI add 


  // common setters and getters for tangled ExB effect
  virtual void SetOmegaTauT1T2(Float_t omegaTau,Float_t t1,Float_t t2) {
    fT1=t1; fT2=t2;
    const Double_t wt0=t2*omegaTau;     fC0=1./(1.+wt0*wt0);
    const Double_t wt1=t1*omegaTau;     fC1=wt1/(1.+wt1*wt1);
  };
  void SetC0C1(Float_t c0,Float_t c1) {fC0=c0;fC1=c1;} // CAUTION: USE WITH CARE
  Float_t GetC0() const {return fC0;}
  Float_t GetC1() const {return fC1;}

  // setters and getters for conical
  void SetCorrectionFactor(Float_t correctionFactor) {fCorrectionFactor=correctionFactor;}
  Float_t GetCorrectionFactor() const {return fCorrectionFactor;}

  void InitSpaceChargeDistortion();

  virtual void Print(const Option_t* option="") const;

protected:
  virtual void GetCorrection(const Float_t x[],const Short_t roc,Float_t dx[]);

private:
  Float_t fC0; // coefficient C0                 (compare Jim Thomas's notes for definitions)
  Float_t fC1; // coefficient C1                 (compare Jim Thomas's notes for definitions)
  Float_t fCorrectionFactor;       // Space Charge Correction factor in comparison to initialized
                                   // look up table which was created for M_mb = 900 and IR = 3000
                                   // compare Internal Note Nr: ???

  TH2 *    fSpaceChargeHistogram;      // Histogram with the input space charge histogram - used as an optional input 
  Bool_t fInitLookUp;                  // flag to check it the Look Up table was created

  Double_t fLookUpErOverEz[kNZ][kNR];  // Array to store electric field integral (int Er/Ez)
  Double_t fLookUpDeltaEz[kNZ][kNR];   // Array to store electric field integral (int Delta Ez)
  // basic numbers for the poisson relaxation //can be set individually in each class
  enum {kRows   =257}; // grid size in r direction used in the poisson relaxation // ( 2**n + 1 ) eg. 65, 129, 257 etc.
  enum {kColumns=129}; // grid size in z direction used in the poisson relaxation // ( 2**m + 1 ) eg. 65, 129, 257 etc.
  enum {kIterations=100}; // Number of iterations within the poisson relaxation 

  ClassDef(AliTPCSpaceCharge,0); 
};

#endif