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

///////////////////////////////////////////////////////////////////////////////
//                                                                           //
// Class containing constant common parameters                               //
//                                                                           //
///////////////////////////////////////////////////////////////////////////////

/* $Id$ */

#include "TObject.h"

class AliTRDpadPlane;

class AliTRDCommonParam : public TObject
{

  public:
  
    enum { kNplan = 6, kNcham = 5, kNsect = 18, kNdet = 540 };
    
    AliTRDCommonParam(const AliTRDCommonParam &p);   
    AliTRDCommonParam &operator=(const AliTRDCommonParam &p); 
    static AliTRDCommonParam *Instance();
    static void     Terminate();
    virtual void    Copy(TObject &p) const;
    
    void            SetField(Float_t field)                        { fField = field; };
    void            SetExB(Int_t exbOn = 1)                        { fExBOn = exbOn; };
    
    Float_t         GetField()                               const { return fField;  };
    Bool_t          ExBOn()                                  const { return fExBOn;  };
    
    AliTRDpadPlane *GetPadPlane(Int_t p, Int_t c) const;
    Int_t           GetRowMax(Int_t p, Int_t c, Int_t /*s*/) const;
    Int_t           GetColMax(Int_t p) const;
    Double_t        GetRow0(Int_t p, Int_t c, Int_t /*s*/) const;
    Double_t        GetCol0(Int_t p) const;
  
  protected:

    static AliTRDCommonParam *fgInstance;     //  Instance of this class (singleton implementation)
    static Bool_t             fgTerminated;   //  Defines if this class has already been terminated
    
    void Init();
    
    Float_t                   fField;         //  Magnetic field
    Int_t                     fExBOn;         //  Switch for the ExB effects
  
    TObjArray                *fPadPlaneArray; //! Array of pad plane objects
  
  private:

    // This is a singleton, constructor is private!  
    AliTRDCommonParam();
    virtual ~AliTRDCommonParam();
  
    ClassDef(AliTRDCommonParam,1)             // The constant parameters common to simulation and reconstruction       

};

#endif