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// $Id: G4VEmProcess.hh,v 1.4 2004/05/17 09:46:56 vnivanch Exp $
// GEANT4 tag $Name: geant4-06-02 $
//
// -------------------------------------------------------------------
//
// GEANT4 Class header file
//
//
// File name:     G4VEmProcess
//
// Author:        Vladimir Ivanchenko
//
// Creation date: 01.10.2003
//
// Modifications:
//
//
// Class Description:
//
// It is the unified Rest and/or Discrete process

// -------------------------------------------------------------------
//

#ifndef G4VEmProcess_h
#define G4VEmProcess_h 1

#include "G4VRestDiscreteProcess.hh"
#include "globals.hh"
#include "G4Material.hh"
#include "G4MaterialCutsCouple.hh"
#include "G4Track.hh"
#include "G4EmModelManager.hh"
#include "G4UnitsTable.hh"
#include "G4ParticleDefinition.hh"

class G4Step;
class G4VEmModel;
class G4VEmFluctuationModel;
class G4DataVector;
class G4VParticleChange;
class G4PhysicsTable;
class G4PhysicsVector;

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

class G4VEmProcess : public G4VRestDiscreteProcess
{
public:

  G4VEmProcess(const G4String& name,
                     G4ProcessType type = fElectromagnetic);

 ~G4VEmProcess();

  G4VParticleChange* PostStepDoIt(const G4Track&, const G4Step&);

  G4double GetMeanLifeTime(const G4Track& aTrack,
                                 G4ForceCondition* condition);
       // It is invoked by the ProcessManager of the Positron if this
       // e+ has a kinetic energy null. Then it return 0 to force the
       // call of AtRestDoIt.
       // This function overloads a virtual function of the base class.

  virtual G4VParticleChange* AtRestDoIt(const G4Track& aTrack,
                                        const G4Step& aStep);
       // It computes the final state of the process:
       //          e+ (at rest) e- (at rest)  ---> gamma gamma,
       // returned as a ParticleChange object.
       // This function overloads a virtual function of the base class.
       // It is invoked by the ProcessManager of the Particle.

  virtual void SecondariesPostStep(G4VEmModel*,
                             const G4MaterialCutsCouple*,
                             const G4DynamicParticle*,
                                   G4double& tcut,
                                   G4double& kinEnergy) = 0;

  virtual G4bool IsApplicable(const G4ParticleDefinition& p) = 0;
    // True for all charged particles

  virtual void BuildPhysicsTable(const G4ParticleDefinition&);
  // Build physics table during initialisation

  virtual void PrintInfoDefinition();
  // Print out of the class parameters

  G4PhysicsTable* BuildLambdaTable();

  void SetLambdaBinning(G4int nbins);
  // Binning for lambda table

  void SetMinKinEnergy(G4double e);
  G4double MinKinEnergy() const;
  // Min kinetic energy for tables

  void SetMaxKinEnergy(G4double e);
  G4double MaxKinEnergy() const;
  // Max kinetic energy for tables

  G4bool StorePhysicsTable(G4ParticleDefinition*,
                     const G4String& directory,
                           G4bool ascii = false);
    // Store PhysicsTable in a file.
    // Return false in case of failure at I/O

  G4bool RetrievePhysicsTable(G4ParticleDefinition*,
                        const G4String& directory,
                              G4bool ascii);
    // Retrieve Physics from a file.
    // (return true if the Physics Table can be build by using file)
    // (return false if the process has no functionality or in case of failure)
    // File name should is constructed as processName+particleName and the
    // should be placed under the directory specifed by the argument.

  void AddEmModel(G4int, G4VEmModel*, G4VEmFluctuationModel* fluc = 0,
                   const G4Region* region = 0);
  // Add EM model coupled with fluctuation model for the region

  void UpdateEmModel(const G4String&, G4double, G4double);
  // Define new energy range for the model identified by the name

  G4double GetLambda(G4double& kinEnergy, const G4MaterialCutsCouple* couple);
  // It returns the Lambda of the process

  G4double MicroscopicCrossSection(G4double kineticEnergy,
                             const G4MaterialCutsCouple* couple);
  // It returns the cross section of the process for energy/ material

  void SetIntegral(G4bool val) {integral = val;};
  G4bool IsIntegral() const {return integral;}

  G4double MeanFreePath(const G4Track& track,
                              G4double previousStepSize,
                              G4ForceCondition* condition);

  const G4ParticleDefinition* Particle() const;
  const G4ParticleDefinition* SecondaryParticle() const;

  void ActivateFluorescence(G4bool, const G4Region* r = 0);
  void ActivateAugerElectronProduction(G4bool, const G4Region* r = 0);

  void SetLambdaFactor(G4double val);

protected:

  void SetParticle(const G4ParticleDefinition* p);
  void SetSecondaryParticle(const G4ParticleDefinition* p);

  virtual G4double GetMeanFreePath(const G4Track& track,
                                         G4double previousStepSize,
                                         G4ForceCondition* condition);

  virtual G4PhysicsVector* LambdaPhysicsVector(const G4MaterialCutsCouple*);

  virtual G4double MinPrimaryEnergy(const G4ParticleDefinition*,
                                    const G4Material*, G4double cut) = 0;

  G4VEmModel* SelectModel(G4double& kinEnergy);

  size_t CurrentMaterialCutsCoupleIndex() const {return currentMaterialIndex;};

  void      ResetNumberOfInteractionLengthLeft();
  // reset (determine the value of)NumberOfInteractionLengthLeft

private:

  void Initialise();

  void DefineMaterial(const G4MaterialCutsCouple* couple);

  G4double GetLambda(G4double kinEnergy);

  void ComputeLambda(G4double kinEnergy);

  // hide  assignment operator

  G4VEmProcess(G4VEmProcess &);
  G4VEmProcess & operator=(const G4VEmProcess &right);

// =====================================================================

private:

  G4EmModelManager*           modelManager;

  // tables and vectors
  G4PhysicsTable*             theLambdaTable;
  G4double*                   theEnergyOfCrossSectionMax;
  G4double*                   theCrossSectionMax;

  const G4ParticleDefinition* particle;
  const G4ParticleDefinition* baseParticle;
  const G4ParticleDefinition* secondaryParticle;
  const G4DataVector*         theCuts;

  // cash
  const G4Material*           currentMaterial;
  const G4MaterialCutsCouple* currentCouple;
  size_t                      currentMaterialIndex;

  G4int                       nLambdaBins;

  G4double                    minKinEnergy;
  G4double                    maxKinEnergy;
  G4double                    lambdaFactor;

  G4double                    preStepLambda;
  G4double                    preStepMFP;
  G4double                    preStepKinEnergy;
  G4double                    mfpKinEnergy;

  G4bool                      integral;
  G4bool                      meanFreePath;
};

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline void G4VEmProcess::DefineMaterial(const G4MaterialCutsCouple* couple)
{
  if(couple != currentCouple) {
    currentCouple   = couple;
    currentMaterial = couple->GetMaterial();
    currentMaterialIndex = couple->GetIndex();
    if(integral && (!meanFreePath || preStepKinEnergy < mfpKinEnergy))
      ResetNumberOfInteractionLengthLeft();
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline G4double G4VEmProcess::GetLambda(G4double& kineticEnergy,
                                  const G4MaterialCutsCouple* couple)
{
  DefineMaterial(couple);
  G4double x = 0.0;
  if(theLambdaTable) x = GetLambda(kineticEnergy);
  return x;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline G4double G4VEmProcess::GetLambda(G4double e)
{
  G4bool b;
  return (((*theLambdaTable)[currentMaterialIndex])->GetValue(e, b));
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline void G4VEmProcess::ComputeLambda(G4double e)
{
  meanFreePath  = false;
  mfpKinEnergy  = 0.0;
  G4double emax = theEnergyOfCrossSectionMax[currentMaterialIndex];
  if (e <= emax) preStepLambda = GetLambda(e);
  else {
    e *= lambdaFactor;
    if(e > emax) {
      mfpKinEnergy = e;
      preStepLambda = GetLambda(e);
    } else preStepLambda = theCrossSectionMax[currentMaterialIndex];
  }
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline G4double G4VEmProcess::GetMeanFreePath(const G4Track& track, G4double,
                                                    G4ForceCondition*)
{
  preStepKinEnergy = track.GetKineticEnergy();
  DefineMaterial(track.GetMaterialCutsCouple());
  if (meanFreePath) {
    if (integral) ComputeLambda(preStepKinEnergy);
    else          preStepLambda = GetLambda(preStepKinEnergy);
    if(0.0 < preStepLambda) preStepMFP = 1.0/preStepLambda;
    else                    preStepMFP = DBL_MAX;
  }
  // G4cout<<GetProcessName()<<": e= "<<preStepKinEnergy<<" mfp= "<<preStepMFP<<G4endl;
  return preStepMFP;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline void G4VEmProcess::ResetNumberOfInteractionLengthLeft()
{
  meanFreePath = true;
  G4VProcess::ResetNumberOfInteractionLengthLeft();
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline G4VEmModel* G4VEmProcess::SelectModel(G4double& kinEnergy)
{
  return modelManager->SelectModel(kinEnergy, currentMaterialIndex);
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline const G4ParticleDefinition* G4VEmProcess::Particle() const
{
  return particle;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline const G4ParticleDefinition* G4VEmProcess::SecondaryParticle() const
{
  return secondaryParticle;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline G4double G4VEmProcess::GetMeanLifeTime(const G4Track&,
                                                    G4ForceCondition*)
{
  return 0.0;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

inline G4VParticleChange* G4VEmProcess::AtRestDoIt(const G4Track&,
                                                   const G4Step&)
{
  return 0;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

#endif