/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

// Library class for particle pt and y distributions used for 
// HMPID simulations.
// To be used with AliGenParam.
// The following particle typed can be simulated:
// phi, lambda, k
//
// Author: Annalisa Mastroserio <Annalisa.Mastroserio@ba.infn.it>
//
//

#include <TRandom.h>
#include <TString.h>
#include <AliLog.h>
#include "AliGenRICHlib.h"

ClassImp(AliGenRICHlib)

Int_t AliGenRICHlib::IpPhi(TRandom *)
{
//PDG code
  return 333;     
}

Double_t AliGenRICHlib::PtPhiFlat( Double_t *, Double_t *)
{
// Phi FLAT pt-distribution
  return 1; 
}

Double_t AliGenRICHlib::PtPhiExp( Double_t *x, Double_t *)
{
//phi     EXP  pt-distribution
  return x[0]*TMath::Exp(-x[0]/0.17);   
}

Double_t AliGenRICHlib::YPhiFlat(Double_t *,Double_t *)
{
//phi             y-distribution 
  return 1;
}

//-------------------------------------------------------
//                    LAMBDAS
//-------------------------------------------------------

Int_t AliGenRICHlib::IpLambda(TRandom *)
{
//PDG code
  return 3122;     
}

Double_t AliGenRICHlib::PtLambdaFlat( Double_t *, Double_t *)
{
// Lambda FLAT pt-distribution

  return 1; 
}

Double_t AliGenRICHlib::PtLambdaExp( Double_t *x, Double_t *)
{
//Lambda     EXP  pt-distribution
  return x[0]*TMath::Exp(-x[0]/0.17);   
}

Double_t AliGenRICHlib::YLambdaFlat(Double_t *,Double_t *)
{
  //Lambda             y-distribution 
  return 1;
}


Int_t AliGenRICHlib::IpLambdaBar(TRandom *)
{
//PDG code
  return -3122;     
}

Double_t AliGenRICHlib::PtLambdaBarFlat( Double_t *, Double_t *)
{
// LambdaBar FLAT pt-distribution

  return 1; 
}

Double_t AliGenRICHlib::PtLambdaBarExp( Double_t *x, Double_t *)
{
//LambdaBar     EXP  pt-distribution
  return x[0]*TMath::Exp(-x[0]/0.17);   
}

Double_t AliGenRICHlib::YLambdaBarFlat(Double_t *,Double_t *)
{
  //LambdaBar             y-distribution 
  return 1;
}



//---------------------------------------------------------
//       K0 short
//--------------------------------------------------------

Int_t AliGenRICHlib::IpK0s(TRandom *)
{
//PDG code
  return 310;     
}

Double_t AliGenRICHlib::PtK0sFlat( Double_t *, Double_t *)
{
// K0s FLAT pt-distribution
  return 1; 
}

Double_t AliGenRICHlib::PtK0sExp( Double_t *x, Double_t *)
{
// K0s   EXP  pt-distribution
  return x[0]*TMath::Exp(-x[0]/0.17);   
}

Double_t AliGenRICHlib::YK0sFlat(Double_t *,Double_t *)
{
// K0s             y-distribution 
  return 1;
}




typedef Double_t (*GenFunc)   (Double_t*,  Double_t*);
typedef Int_t    (*GenFuncIp) (TRandom *);

GenFunc AliGenRICHlib::GetPt(Int_t iPID, const char * sForm) const
{
// Return pointer to Pt parameterisation
  AliDebug(1,Form("PID: %i, form: %s",iPID,sForm));	
   TString type(sForm);

   switch(iPID) {
   case kPhi:  
      if     (type=="FLAT")                                         return PtPhiFlat;
      else if(type=="EXP")                                          return PtPhiExp;
      else {
        AliFatal(Form("Unknown Pt distribution form: %s",sForm));   return 0;
       }

   case kLambda0:  
      if     (type=="FLAT")                                         return PtLambdaFlat;
      else if(type=="EXP")                                          return PtLambdaExp;
      else {
        AliFatal(Form("Unknown Pt distribution form: %s",sForm));   return 0;
       }  

   case kLambda0Bar:  
      if     (type=="FLAT")                                         return PtLambdaBarFlat;
      else if(type=="EXP")                                          return PtLambdaBarExp;
      else {
        AliFatal(Form("Unknown Pt distribution form: %s",sForm));   return 0;
       }  


  case kK0Short:  
      if     (type=="FLAT")                                         return PtK0sFlat;
      else if(type=="EXP")                                          return PtK0sExp;
      else {
        AliFatal(Form("Unknown Pt distribution form: %s",sForm));   return 0;
       }

   default : AliFatal(Form("Unknown particle type: %i",iPID));      return 0;
   }//switch
}

GenFunc AliGenRICHlib::GetY(Int_t iPID, const char *sForm) const
{
  AliDebug(1,Form("PID: %i, form: %s",iPID,sForm));	

   switch (iPID) {
   case kPhi:                                                       return YPhiFlat;
   case kLambda0:                                                   return YLambdaFlat;
   case kLambda0Bar:                                                return YLambdaBarFlat;
   case kK0Short:                                                   return YK0sFlat;

   default  : AliFatal(Form("Unknown particle type: %i",iPID));     return 0;

   }//switch
}

GenFuncIp AliGenRICHlib::GetIp(Int_t iPID, const char *sForm) const
{
// Return pointer to particle type parameterisation
  AliDebug(1,Form("PID: %i, form: %s",iPID,sForm));   //////////	
  switch (iPID){
    case kPhi:                                                   return IpPhi;
    case kLambda0:                                               return IpLambda;
    case kLambda0Bar:                                            return IpLambdaBar; 
    case kK0Short:                                               return IpK0s;
    
    default  : AliFatal(Form("Unknown particle type: %i",iPID))  return 0;
  }
}