// GLG4Gen.cc
// Contact person: Phil Jones <p.g.jones@qmul.ac.uk>
// See GLG4Gen.hh for more details
//———————————————————————//

#include <RAT/GLG4Gen.hh>
#include <RAT/GLG4VertexGen.hh>
#include <RAT/GLG4PosGen.hh>
#include <RAT/GLG4TimeGen.hh>
#include <RAT/GLG4StringUtil.hh>

#include <RAT/Factory.hh>

#include <G4Event.hh>
#include <G4Track.hh>
#include <G4PrimaryVertex.hh>
#include <G4PrimaryParticle.hh>
#include <G4ThreeVector.hh>

using namespace std;


GLG4Gen::~GLG4Gen() {
  if (fTimeGen) delete fTimeGen;
  if (fVertexGen) delete fVertexGen;
  if (fPosGen) delete fPosGen;

}

void GLG4Gen::BeginOfRun() {
  if (fTimeGen) fTimeGen->BeginOfRun();
  if (fVertexGen) fVertexGen->BeginOfRun();
  if (fPosGen) fPosGen->BeginOfRun();
}

void GLG4Gen::EndOfRun() {
  if (fTimeGen) fTimeGen->EndOfRun();
  if (fVertexGen) fVertexGen->EndOfRun();
  if (fPosGen) fPosGen->EndOfRun();
}


GLG4Gen_Combo::GLG4Gen_Combo() : GLG4Gen("combo"), fStateStr("")
{
  // Default time generator
  fTimeGen = new GLG4TimeGen_Poisson();
}

GLG4Gen_Combo::~GLG4Gen_Combo()
{
}

void GLG4Gen_Combo::GenerateEvent(G4Event *event)
{
  G4ThreeVector pos;
  fPosGen->GeneratePosition(pos);
  G4double t0 = NextTime();

  fVertexGen->GeneratePrimaryVertex(event, pos, t0);
}

void GLG4Gen_Combo::ResetTime(double offset)
{
  fNextTime = fTimeGen->GenerateEventTime() + offset;
}

void GLG4Gen_Combo::SetState(G4String state)
{
  state = util_strip_default(state);

  vector<string> parts = util_split(state, ":");

  try {
    switch (parts.size()) {
    case 3:
      // last is optional time generator
      delete fTimeGen; fTimeGen = 0; // In case of exception in next line
      fTimeGen = RAT::GlobalFactory<GLG4TimeGen>::New(parts[2]);
    case 2:
      delete fVertexGen; fVertexGen = 0;
      fVertexGen = RAT::GlobalFactory<GLG4VertexGen>::New(parts[0]);
      delete fPosGen; fPosGen = 0;
      fPosGen = RAT::GlobalFactory<GLG4PosGen>::New(parts[1]);
      break;
    default:
      G4Exception(__FILE__, "Invalid Parameter", FatalException, ("Combo generator syntax error: "+state).c_str());
      break;
    }

    fStateStr = state; // Save for later call to GetState()
  } catch (RAT::FactoryUnknownID &unknown) {
    G4cerr << "Unknown generator \"" << unknown.id << "\"" << G4endl;
  }
}

G4String GLG4Gen_Combo::GetState() const
{
  return fStateStr;
}

void GLG4Gen_Combo::SetTimeState(G4String state)
{
  if (fTimeGen)
    fTimeGen->SetState(state);
  else
    G4cerr << "GLG4Gen_Combo error: Cannot set time state, no time generator selected" << G4endl;
}

G4String GLG4Gen_Combo::GetTimeState() const
{
  if (fTimeGen)
    return fTimeGen->GetState();
  else
    return G4String("GLG4Gen_Combo error: no time generator selected");
}

void GLG4Gen_Combo::SetVertexState(G4String state)
{
  if (fVertexGen)
    fVertexGen->SetState(state);
  else
    G4cerr << "GLG4Gen_Combo error: Cannot set vertex state, no vertex generator selected" << G4endl;
}

G4String GLG4Gen_Combo::GetVertexState() const
{
  if (fVertexGen)
    return fVertexGen->GetState();
  else
    return G4String("GLG4Gen_Combo error: no vertex generator selected");
}

void GLG4Gen_Combo::SetPosState(G4String state)
{
  if (fPosGen)
    fPosGen->SetState(state);
  else
    G4cerr << "GLG4Gen_Combo error: Cannot set position state, no position generator selected" << G4endl;
}


G4String GLG4Gen_Combo::GetPosState() const
{
  if (fPosGen)
    return fPosGen->GetState();
  else
    return G4String("GLG4Gen_Combo error: no pos generator selected");
}


////////////////////////////////////////////////////////////////


GLG4Gen_DeferTrack::GLG4Gen_DeferTrack(const G4Track *track) : GLG4Gen("defer_track")
{
  fVertex = new G4PrimaryVertex( track->GetPosition(),
			       track->GetGlobalTime() );

  G4ThreeVector mom(track->GetMomentum());
  G4ThreeVector pol(track->GetPolarization());
  G4PrimaryParticle* particle;
  particle=
    new G4PrimaryParticle(track->GetDefinition(),// particle code
			  mom.x(), mom.y(), mom.z() );// momentum
  particle->SetPolarization(pol.x(), pol.y(), pol.z()); // polarization
  particle->SetMass(track->GetDefinition()->GetPDGMass()); // Geant4 is silly.

  fVertex->SetPrimary( particle );

  fNextTime = fVertex->GetT0();
}

GLG4Gen_DeferTrack::~GLG4Gen_DeferTrack()
{
}

void GLG4Gen_DeferTrack::GenerateEvent(G4Event *event)
{
  fVertex->SetT0(fNextTime);
  event->AddPrimaryVertex(fVertex);
}

void GLG4Gen_DeferTrack::SetState(G4String /*state*/)
{
  // No-op
}

G4String GLG4Gen_DeferTrack::GetState() const
{
  return G4String("");
}