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// The lust update: M.V. Kossov, CERN/ITEP(Moscow) 17-June-02
// GEANT4 tag $Name: geant4-09-03 $
//
//
// G4 Physics class: G4QAntiBaryonPlusNuclearCrossSection for gamma+A cross sections
// Created: M.V. Kossov, CERN/ITEP(Moscow), 20-Dec-03
// The last update: M.V. Kossov, CERN/ITEP (Moscow) 15-Feb-04
// --------------------------------------------------------------------------------
// ****************************************************************************************
// ***** This HEADER is a property of the CHIPS hadronic package in Geant4 (M. Kosov) *****
// *********** DO NOT MAKE ANY CHANGE without approval of Mikhail.Kossov@cern.ch **********
// ****************************************************************************************
// Short description: CHIPS cross-sections for AntiBaryon(plus)-nuclear interactions
// -------------------------------------------------------------------------------------
//
//#define debug
//#define pdebug
//#define debug3
//#define debugn
//#define debugs

#include "G4QAntiBaryonPlusNuclearCrossSection.hh"

// Initialization of the
G4double* G4QAntiBaryonPlusNuclearCrossSection::lastLEN=0; // PointerToLastArray ofLowEn CS
G4double* G4QAntiBaryonPlusNuclearCrossSection::lastHEN=0; // PointerToLastArray ofHighEnCS
G4int     G4QAntiBaryonPlusNuclearCrossSection::lastN=0;   // TheLastN of calculatedNucleus
G4int     G4QAntiBaryonPlusNuclearCrossSection::lastZ=0;   // TheLastZ of calculatedNucleus
G4double  G4QAntiBaryonPlusNuclearCrossSection::lastP=0.;  // LastUsedCrossSectionMomentum
G4double  G4QAntiBaryonPlusNuclearCrossSection::lastTH=0.; // Last threshold momentum
G4double  G4QAntiBaryonPlusNuclearCrossSection::lastCS=0.; // LastValue of the CrossSection
G4int     G4QAntiBaryonPlusNuclearCrossSection::lastI=0;   // TheLastPosition in the DAMDB
std::vector<G4double*>* G4QAntiBaryonPlusNuclearCrossSection::LEN =
                                                                new std::vector<G4double*>;
std::vector<G4double*>* G4QAntiBaryonPlusNuclearCrossSection::HEN =
                                                                new std::vector<G4double*>;

// Returns Pointer to the G4VQCrossSection class
G4VQCrossSection* G4QAntiBaryonPlusNuclearCrossSection::GetPointer()
{
  static G4QAntiBaryonPlusNuclearCrossSection theCrossSection;//Static body of CrossSection
  return &theCrossSection;
}

G4QAntiBaryonPlusNuclearCrossSection::~G4QAntiBaryonPlusNuclearCrossSection()
{
  G4int lens=LEN->size();
  for(G4int i=0; i<lens; ++i) delete[] (*LEN)[i];
  delete LEN;
  G4int hens=HEN->size();
  for(G4int i=0; i<hens; ++i) delete[] (*HEN)[i];
  delete HEN;
}

// The main member function giving the collision cross section (P is in IU, CS is in mb)
// Make pMom in independent units ! (Now it is MeV)
G4double G4QAntiBaryonPlusNuclearCrossSection::GetCrossSection(G4bool fCS, G4double pMom,
                                                       G4int tgZ, G4int tgN, G4int PDG)
{
  static G4double tolerance=0.001;     // Tolerance (0.1%) to consider as "the same mom"
  static G4int j;                      // A#0f Z/N-records already tested in AMDB
  static std::vector <G4int>    colN;  // Vector of N for calculated nuclei (isotops)
  static std::vector <G4int>    colZ;  // Vector of Z for calculated nuclei (isotops)
  static std::vector <G4double> colP;  // Vector of last momenta for the reaction
  static std::vector <G4double> colTH; // Vector of energy thresholds for the reaction
  static std::vector <G4double> colCS; // Vector of last cross sections for the reaction
  // ***---*** End of the mandatory Static Definitions of the Associative Memory ***---***
#ifdef debug
  G4cout<<"G4QPrCS::GetCS:>>> f="<<fCS<<", p="<<pMom<<", Z="<<tgZ<<"("<<lastZ<<") ,N="<<tgN
        <<"("<<lastN<<"),PDG=2212, thresh="<<lastTH<<",Sz="<<colN.size()<<G4endl;
#endif
  if(PDG!=-3112 && PDG!=-3312 && PDG!=-3334)
    G4cout<<"-Warning-G4QAntiBaryonPlusCS::GetCS: Not a PositiveAntiBar,PDG="<<PDG<<G4endl;
  G4bool in=false;                     // By default the isotope must be found in the AMDB
  if(tgN!=lastN || tgZ!=lastZ)         // The nucleus was not the last used isotope
  {
    in = false;                        // By default the isotope haven't be found in AMDB  
    lastP   = 0.;                      // New momentum history (nothing to compare with)
    lastN   = tgN;                     // The last N of the calculated nucleus
    lastZ   = tgZ;                     // The last Z of the calculated nucleus
    lastI   = colN.size();             // Size of the Associative Memory DB in the heap
    j  = 0;                            // A#0f records found in DB for this projectile
#ifdef debug
    G4cout<<"G4QPrCS::GetCS: the amount of records in the AMDB lastI="<<lastI<<G4endl;
#endif
    if(lastI) for(G4int i=0; i<lastI; i++) // AMDB exists, try to find the (Z,N) isotope
    {
      if(colN[i]==tgN && colZ[i]==tgZ) // Try the record "i" in the AMDB
      {
        lastI=i;                       // Remember the index for future fast/last use
        lastTH =colTH[i];              // The last THreshold (A-dependent)
#ifdef debug
        G4cout<<"G4QPrCS::GetCS:*Found* P="<<pMom<<",Threshold="<<lastTH<<",j="<<j<<G4endl;
#endif
        if(pMom<=lastTH)
        {
#ifdef debug
          G4cout<<"G4QPCS::GetCS:Found,P="<<pMom<<" < Threshold="<<lastTH<<",CS=0"<<G4endl;
#endif
          return 0.;                   // Energy is below the Threshold value
        }
        lastP  =colP [i];              // Last Momentum  (A-dependent)
        lastCS =colCS[i];              // Last CrossSect (A-dependent)
        if(std::fabs(lastP-pMom)<tolerance*pMom)
        //if(lastP==pMom)              // VI do not use tolerance
        {
#ifdef debug
          G4cout<<"..G4QPrCS::GetCS:.DoNothing.P="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
#endif
          //CalculateCrossSection(fCS,-1,j,2212,lastZ,lastN,pMom); // Update param's only
          return lastCS*millibarn;     // Use theLastCS
        }
        in = true;                     // This is the case when the isotop is found in DB
        // Momentum pMom is in IU ! @@ Units
#ifdef debug
        G4cout<<"G4QPrCS::G:UpdatDB P="<<pMom<<",f="<<fCS<<",lI="<<lastI<<",j="<<j<<G4endl;
#endif
        lastCS=CalculateCrossSection(fCS,-1,j,2212,lastZ,lastN,pMom); // read & update
#ifdef debug
        G4cout<<"G4QPrCS::GetCrosSec: *****> New (inDB) Calculated CS="<<lastCS<<G4endl;
#endif
        if(lastCS<=0. && pMom>lastTH)  // Correct the threshold (@@ No intermediate Zeros)
        {
#ifdef debug
          G4cout<<"G4QPrCS::GetCS: New P="<<pMom<<"(CS=0) > Threshold="<<lastTH<<G4endl;
#endif
          lastCS=0.;
          lastTH=pMom;
        }
        break;                         // Go out of the LOOP
      }
#ifdef debug
      G4cout<<"-->G4QPrCrossSec::GetCrosSec: pPDG=2212, j="<<j<<", N="<<colN[i]
            <<",Z["<<i<<"]="<<colZ[i]<<G4endl;
#endif
      j++;                             // Increment a#0f records found in DB
    }
#ifdef debug
    G4cout<<"-?-G4QPrCS::GetCS:RC Z="<<tgZ<<",N="<<tgN<<",in="<<in<<",j="<<j<<" ?"<<G4endl;
#endif
    if(!in)                            // This isotope has not been calculated previously
    {
#ifdef debug
      G4cout<<"^^^G4QPrCS::GetCS:CalcNew P="<<pMom<<", f="<<fCS<<", lastI="<<lastI<<G4endl;
#endif
      //!!The slave functions must provide cross-sections in millibarns (mb) !! (not in IU)
      lastCS=CalculateCrossSection(fCS,0,j,2212,lastZ,lastN,pMom); //calculate & create
      //if(lastCS>0.)                   // It means that the AMBD was initialized
      //{

        lastTH = ThresholdEnergy(tgZ, tgN); // The Threshold Energy which is now the last
#ifdef debug
        G4cout<<"G4QPrCrossSection::GetCrossSect: NewThresh="<<lastTH<<",P="<<pMom<<G4endl;
#endif
        colN.push_back(tgN);
        colZ.push_back(tgZ);
        colP.push_back(pMom);
        colTH.push_back(lastTH);
        colCS.push_back(lastCS);
#ifdef debug
        G4cout<<"G4QPrCS::GetCrosSec:recCS="<<lastCS<<",lZ="<<lastN<<",lN="<<lastZ<<G4endl;
#endif
      //} // M.K. Presence of H1 with high threshold breaks the syncronization
#ifdef pdebug
      G4cout<<"G4QPrCS::GetCS:1st,P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
#endif
      return lastCS*millibarn;
    } // End of creation of the new set of parameters
    else
    {
#ifdef debug
      G4cout<<"G4QPrCS::GetCS: Update lastI="<<lastI<<",j="<<j<<G4endl;
#endif
      colP[lastI]=pMom;
      colCS[lastI]=lastCS;
    }
  } // End of parameters udate
  else if(pMom<=lastTH)
  {
#ifdef debug
    G4cout<<"G4QPrCS::GetCS: Current P="<<pMom<<" < Threshold="<<lastTH<<", CS=0"<<G4endl;
#endif
    return 0.;                         // Momentum is below the Threshold Value -> CS=0
  }
  else if(std::fabs(lastP-pMom)<tolerance*pMom)
  //else if(lastP==pMom)               // VI do not use tolerance
  {
#ifdef debug
    G4cout<<"..G4QPCS::GetCS:OldNZ&P="<<lastP<<"="<<pMom<<",CS="<<lastCS*millibarn<<G4endl;
#endif
    return lastCS*millibarn;           // Use theLastCS
  }
  else                                 // It is the last used -> use the current tables
  {
#ifdef debug
    G4cout<<"-!-G4QPCS::GetCS:UseCur P="<<pMom<<",f="<<fCS<<",I="<<lastI<<",j="<<j<<G4endl;
#endif
    lastCS=CalculateCrossSection(fCS,1,j,2212,lastZ,lastN,pMom); // Only read and UpdateDB
    lastP=pMom;
  }
#ifdef debug
  G4cout<<"==>G4QPrCS::GetCroSec: P="<<pMom<<"(MeV),CS="<<lastCS*millibarn<<"(mb)"<<G4endl;
#endif
  return lastCS*millibarn;
}

// The main member function giving the gamma-A cross section (E in GeV, CS in mb)
G4double G4QAntiBaryonPlusNuclearCrossSection::CalculateCrossSection(G4bool, G4int F, G4int I,
                                        G4int, G4int targZ, G4int targN, G4double Momentum)
{
  static const G4double THmin=27.;     // default minimum Momentum (MeV/c) Threshold
  static const G4double THmiG=THmin*.001; // minimum Momentum (GeV/c) Threshold
  static const G4double dP=10.;        // step for the LEN (Low ENergy) table MeV/c
  static const G4double dPG=dP*.001;   // step for the LEN (Low ENergy) table GeV/c
  static const G4int    nL=105;        // A#of LEN points in E (step 10 MeV/c)
  static const G4double Pmin=THmin+(nL-1)*dP; // minP for the HighE part with safety
  static const G4double Pmax=227000.;  // maxP for the HEN (High ENergy) part 227 GeV
  static const G4int    nH=224;        // A#of HEN points in lnE
  static const G4double milP=std::log(Pmin);// Low logarithm energy for the HEN part
  static const G4double malP=std::log(Pmax);// High logarithm energy (each 2.75 percent)
  static const G4double dlP=(malP-milP)/(nH-1); // Step in log energy in the HEN part
  static const G4double milPG=std::log(.001*Pmin);// Low logarithmEnergy for HEN part GeV/c
#ifdef debug
  G4cout<<"G4QProtNCS::CalCS:N="<<targN<<",Z="<<targZ<<",P="<<Momentum<<">"<<THmin<<G4endl;
#endif
  G4double sigma=0.;
  if(F&&I) sigma=0.;                   // @@ *!* Fake line *!* to use F & I !!!Temporary!!!
  G4double A=targN+targZ;              // A of the target
#ifdef debug
  G4cout<<"G4QProtNucCS::CalCS: A="<<A<<",F="<<F<<",I="<<I<<",nL="<<nL<<",nH="<<nH<<G4endl;
#endif
  if(F<=0)                             // This isotope was not the last used isotop
  {
    if(F<0)                            // This isotope was found in DAMDB =======> RETRIEVE
    {
      G4int sync=LEN->size();
      if(sync<=I) G4cerr<<"*!*G4QPiMinusNuclCS::CalcCrosSect:Sync="<<sync<<"<="<<I<<G4endl;
      lastLEN=(*LEN)[I];               // Pointer to prepared LowEnergy cross sections
      lastHEN=(*HEN)[I];               // Pointer to prepared High Energy cross sections
    }
    else                               // This isotope wasn't calculated before => CREATE
    {
      lastLEN = new G4double[nL];      // Allocate memory for the new LEN cross sections
      lastHEN = new G4double[nH];      // Allocate memory for the new HEN cross sections
      // --- Instead of making a separate function ---
      G4double P=THmiG;                // Table threshold in GeV/c
      for(G4int m=0; m<nL; m++)
      {
        lastLEN[m] = CrossSectionLin(targZ, targN, P);
        P+=dPG;
      }
      G4double lP=milPG;
      for(G4int n=0; n<nH; n++)
      {
        lastHEN[n] = CrossSectionLog(targZ, targN, lP);
        lP+=dlP;
      }
#ifdef debug
      G4cout<<"-*->G4QPr0tNucCS::CalcCS:Tab for Z="<<targZ<<",N="<<targN<<",I="<<I<<G4endl;
#endif
      // --- End of possible separate function
      // *** The synchronization check ***
      G4int sync=LEN->size();
      if(sync!=I)
      {
        G4cerr<<"***G4QPiMinusNuclCS::CalcCrossSect: Sinc="<<sync<<"#"<<I<<", Z=" <<targZ
              <<", N="<<targN<<", F="<<F<<G4endl;
        //G4Exception("G4PiMinusNuclearCS::CalculateCS:","39",FatalException,"DBoverflow");
      }
      LEN->push_back(lastLEN);         // remember the Low Energy Table
      HEN->push_back(lastHEN);         // remember the High Energy Table
    } // End of creation of the new set of parameters
  } // End of parameters udate
  // ============================== NOW the Magic Formula =================================
#ifdef debug
  G4cout<<"G4QPrNCS::CalcCS:lTH="<<lastTH<<",Pmi="<<Pmin<<",dP="<<dP<<",dlP="<<dlP<<G4endl;
#endif
  if (Momentum<lastTH) return 0.;      // It must be already checked in the interface class
  else if (Momentum<Pmin)              // High Energy region
  {
#ifdef debug
    G4cout<<"G4QPrNCS::CalcCS:bLEN A="<<A<<", nL="<<nL<<",TH="<<THmin<<",dP="<<dP<<G4endl;
#endif
    if(A<=1.) sigma=0.;
    else      sigma=EquLinearFit(Momentum,nL,THmin,dP,lastLEN);
#ifdef debugn
    if(sigma<0.)
      G4cout<<"G4QPrNuCS::CalcCS:A="<<A<<",E="<<Momentum<<",T="<<THmin<<",dP="<<dP<<G4endl;
#endif
  }
  else if (Momentum<Pmax)              // High Energy region
  {
    G4double lP=std::log(Momentum);
#ifdef debug
    G4cout<<"G4QProtNucCS::CalcCS: before HEN nH="<<nH<<",iE="<<milP<<",dlP="<<dlP<<G4endl;
#endif
    sigma=EquLinearFit(lP,nH,milP,dlP,lastHEN);
  }
  else                                 // UHE region (calculation, not frequent)
  {
    G4double P=0.001*Momentum;         // Approximation formula is for P in GeV/c
    sigma=CrossSectionFormula(targZ, targN, P, std::log(P));
  }
#ifdef debug
  G4cout<<"G4QAntiBaryonPlusNuclearCrossSection::CalcCS: CS="<<sigma<<G4endl;
#endif
  if(sigma<0.) return 0.;
  return sigma;
}

// Electromagnetic momentum-threshold (in MeV/c) 
G4double G4QAntiBaryonPlusNuclearCrossSection::ThresholdMomentum(G4int tZ, G4int tN)
{
  static const G4double third=1./3.;
  static const G4double prM = G4QPDGCode(2212).GetMass(); // Proton mass in MeV
  static const G4double pM = G4QPDGCode(3112).GetMass(); // Projectile mass in MeV
  static const G4double tpM= pM+pM;       // Doubled projectile mass (MeV)
  G4double tA=tZ+tN;
  if(tZ<.99 || tN<0.) return 0.;
  G4double dE=tZ/(1.+std::pow(tA,third)); // Safety for diffused edge of the nucleus (QE)
  G4double tM=931.5*tA;
  if(tZ==1 && tN==0) tM=prM;    // A threshold on the free proton
  G4double T=dE+dE*(dE/2+pM)/tM;
  return std::sqrt(T*(tpM+T));
}

// Calculation formula for piMinus-nuclear inelastic cross-section (mb) (P in GeV/c)
G4double G4QAntiBaryonPlusNuclearCrossSection::CrossSectionLin(G4int tZ, G4int tN,
                                                               G4double P)
{
  G4double lP=std::log(P);
  return CrossSectionFormula(tZ, tN, P, lP);
}

// Calculation formula for piMinus-nuclear inelastic cross-section (mb) log(P in GeV/c)
G4double G4QAntiBaryonPlusNuclearCrossSection::CrossSectionLog(G4int tZ, G4int tN,
                                                               G4double lP)
{
  G4double P=std::exp(lP);
  return CrossSectionFormula(tZ, tN, P, lP);
}
// Calculation formula for piMinus-nuclear inelastic cross-section (mb) log(P in GeV/c)
G4double G4QAntiBaryonPlusNuclearCrossSection::CrossSectionFormula(G4int tZ, G4int tN,
                                                                   G4double P, G4double lP)
{
  G4double sigma=0.;
  if(tZ==1 && !tN)                        // AntiBar-Prot interaction from G4QuasiElRatios
  {
    G4double ld=lP-3.5;
    G4double ld2=ld*ld;
    G4double ye=std::exp(lP*1.25);
    G4double yt=std::exp(lP*0.35);
    G4double El=80./(ye+1.);
    G4double To=(80./yt+.3)/yt;
    sigma=(To-El)+.2443*ld2+31.48;
  }
  else if(tZ==1 && tN==1)
  {
    G4double p2=P*P;
    G4double p4=p2*p2;
    G4double r=lP-3.7;
    sigma=(0.6*r*r+67.+90.*std::exp(-lP*.666))/(1.+4.E-7/p4/p4);
  }
  else if(tZ<97 && tN<152)                // General solution
  {
    G4double d=lP-4.2;
    G4double sp=std::sqrt(P);
    G4double p2=P*P;
    G4double p4=p2*p2;
    G4double a=tN+tZ;                      // A of the target
    G4double sa=std::sqrt(a);
    G4double a2=a*a;
    G4double a3=a2*a;
    G4double a4=a2*a2;
    G4double a2s=a2*sa;
    G4double c=(170.+3600./a2s)/(1.+65./a2s)+40.*std::pow(a,0.712)/(1.+12.2/a)/(1.+34./a2);
    G4double r=(170.+0.01*a3)/(1.+a3/28000.);
    G4double h=.016*(1.+1.5E-8*a3*a2s)/a4;
    sigma=(c+d*d+r/sp)/(1.+h/p4/p4);
#ifdef pdebug
    G4cout<<"G4QAntiBarPlNucCS::CSForm: A="<<a<<",P="<<P<<",CS="<<sigma<<",c="<<c<<",g="<<g
          <<",d="<<d<<",r="<<r<<",e="<<e<<",h="<<h<<G4endl;
#endif
  }
  else
  {
    G4cerr<<"-Warning-G4QAntiBarPlNuclCroSect::CSForm:*Bad A* Z="<<tZ<<", N="<<tN<<G4endl;
    sigma=0.;
  }
  if(sigma<0.) return 0.;
  return sigma;  
}
