#include "METOOLS/Explicit/Lorentz_Calculator.H"
#include "METOOLS/Currents/C_Scalar.H"
#include "METOOLS/Currents/C_Spinor.H"
#include "METOOLS/Currents/C_Vector.H"
#include "METOOLS/Explicit/Vertex.H"
#include "MODEL/Main/Single_Vertex.H"
#include "ATOOLS/Org/Message.H"
#include "ATOOLS/Org/Exception.H"
#include "ATOOLS/Math/MyComplex.H"


namespace METOOLS {

  template <typename SType>
  class FF2_Calculator: public Lorentz_Calculator {
  public:

    typedef std::complex<SType> SComplex;

    const SComplex I = SComplex(0.0,1.0);
    
    FF2_Calculator(const Vertex_Key &key):
      Lorentz_Calculator(key) {}

    std::string Label() const { return "FF2"; }

    CObject *Evaluate(const CObject_Vector &jj)
    {

// if outgoing index is 0
if (p_v->V()->id.back()==0){
const CSpinor <SType> & j1 = ((jj[0]->Get< CSpinor <SType> >())->B() == -1) ? (*(jj[0]->Get< CSpinor <SType> >())) : (*(jj[0]->Get< CSpinor <SType> >())).CConj() ;
const SComplex & j10 = j1[0];
const SComplex & j11 = j1[1];
const SComplex & j12 = j1[2];
const SComplex & j13 = j1[3];
CSpinor<SType>* j0 = NULL;
switch(+(j1.On()<<(2))){
case 4:
j0 = CSpinor<SType>::New(m_r[0],-1,0,0,0,0,1);
(*j0)[0] = 1.0*j10;
(*j0)[1] = 1.0*j11;
(*j0)[2] = 0;
(*j0)[3] = 0;
j0->SetS(j1.S());
return j0;
case 8:
return j0;
case 12:
j0 = CSpinor<SType>::New(m_r[0],-1,0,0,0,0,1);
(*j0)[0] = 1.0*j10;
(*j0)[1] = 1.0*j11;
(*j0)[2] = 0;
(*j0)[3] = 0;
j0->SetS(j1.S());
return j0;
default:
 THROW(fatal_error, "Massless spinor optimization error in Lorentz calculator");
}

}

// if outgoing index is 1
if (p_v->V()->id.back()==1){
const CSpinor <SType> & j0 = ((jj[0]->Get< CSpinor <SType> >())->B() == 1) ? (*(jj[0]->Get< CSpinor <SType> >())) : (*(jj[0]->Get< CSpinor <SType> >())).CConj() ;
const SComplex & j00 = j0[0];
const SComplex & j01 = j0[1];
const SComplex & j02 = j0[2];
const SComplex & j03 = j0[3];
CSpinor<SType>* j1 = NULL;
switch(+(j0.On()<<(0))){
case 1:
j1 = CSpinor<SType>::New(m_r[1],1,0,0,0,0,1);
(*j1)[0] = 1.0*j00;
(*j1)[1] = 1.0*j01;
(*j1)[2] = 0;
(*j1)[3] = 0;
j1->SetS(j0.S());
return j1;
case 2:
return j1;
case 3:
j1 = CSpinor<SType>::New(m_r[1],1,0,0,0,0,1);
(*j1)[0] = 1.0*j00;
(*j1)[1] = 1.0*j01;
(*j1)[2] = 0;
(*j1)[3] = 0;
j1->SetS(j0.S());
return j1;
default:
 THROW(fatal_error, "Massless spinor optimization error in Lorentz calculator");
}

}

      THROW(fatal_error, "Internal error in Lorentz calculator");
      return NULL;
    }

  };// end of class FF2_Calculator

  template class FF2_Calculator<double>;

}// end of namespace METOOLS


using namespace METOOLS;

DECLARE_GETTER(FF2_Calculator<double>,"DFF2",
	       Lorentz_Calculator,Vertex_Key);
Lorentz_Calculator *ATOOLS::Getter
<Lorentz_Calculator,Vertex_Key,FF2_Calculator<double> >::
operator()(const Vertex_Key &key) const
{ return new FF2_Calculator<double>(key); }

void ATOOLS::Getter<Lorentz_Calculator,Vertex_Key,
		    FF2_Calculator<double> >::
PrintInfo(std::ostream &str,const size_t width) const
{ str<<"FF2 vertex"; }