/*************************************************************************************

Grid physics library, www.github.com/paboyle/Grid

Source file: ./lib/qcd/action/fermion/MobiusEOFAFermioncache.cc

Copyright (C) 2017

Author: Peter Boyle <pabobyle@ph.ed.ac.uk>
Author: Peter Boyle <paboyle@ph.ed.ac.uk>
Author: Peter Boyle <peterboyle@Peters-MacBook-Pro-2.local>
Author: paboyle <paboyle@ph.ed.ac.uk>
Author: David Murphy <dmurphy@phys.columbia.edu>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

See the full license in the file "LICENSE" in the top level distribution directory
*************************************************************************************/
			   /*  END LEGAL */

#include <Grid/qcd/action/fermion/FermionCore.h>
#include <Grid/qcd/action/fermion/MobiusEOFAFermion.h>

NAMESPACE_BEGIN(Grid);

template<class Impl>
void MobiusEOFAFermion<Impl>::M5D(const FermionField &psi_i, const FermionField &phi_i, FermionField &chi_i,
				  std::vector<Coeff_t> &lower, std::vector<Coeff_t> &diag, std::vector<Coeff_t> &upper)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  auto psi = psi_i.View();
  auto phi = phi_i.View();
  auto chi = chi_i.View();

  assert(phi.Checkerboard() == psi.Checkerboard());

  // Flops = 6.0*(Nc*Ns) *Ls*vol
  this->M5Dcalls++;
  this->M5Dtime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{
    for(int s=0; s<Ls; s++){
      auto tmp = psi[0];
      if(s==0){
	spProj5m(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5p(tmp, psi[ss+Ls-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else if(s==(Ls-1)) {
	spProj5m(tmp, psi[ss+0]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5p(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else {
	spProj5m(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5p(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      }
    }
  });

  this->M5Dtime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::M5D_shift(const FermionField &psi_i, const FermionField &phi_i, FermionField &chi_i,
					std::vector<Coeff_t> &lower, std::vector<Coeff_t> &diag, std::vector<Coeff_t> &upper,
					std::vector<Coeff_t> &shift_coeffs)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  auto psi = psi_i.View();
  auto phi = phi_i.View();
  auto chi = chi_i.View();

  int shift_s = (this->pm == 1) ? (Ls-1) : 0; // s-component modified by shift operator

  assert(phi.Checkerboard() == psi.Checkerboard());

  // Flops = 6.0*(Nc*Ns) *Ls*vol
  this->M5Dcalls++;
  this->M5Dtime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{
    for(int s=0; s<Ls; s++){
      auto tmp = psi[0];
      if(s==0){
	spProj5m(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5p(tmp, psi[ss+Ls-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else if(s==(Ls-1)) {
	spProj5m(tmp, psi[ss+0]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5p(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else {
	spProj5m(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5p(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      }
      if(this->pm == 1){ spProj5p(tmp, psi[ss+shift_s]); }
      else{ spProj5m(tmp, psi[ss+shift_s]); }
      chi[ss+s] = chi[ss+s] + shift_coeffs[s]*tmp;
    }
  });

  this->M5Dtime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::M5Ddag(const FermionField &psi_i, const FermionField &phi_i, FermionField &chi_i,
				     std::vector<Coeff_t> &lower, std::vector<Coeff_t> &diag, std::vector<Coeff_t> &upper)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  auto psi = psi_i.View();
  auto phi = phi_i.View();
  auto chi = chi_i.View();

  assert(phi.Checkerboard() == psi.Checkerboard());

  // Flops = 6.0*(Nc*Ns) *Ls*vol
  this->M5Dcalls++;
  this->M5Dtime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{
    auto tmp = psi[0];
    for(int s=0; s<Ls; s++){
      if(s==0) {
	spProj5p(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5m(tmp, psi[ss+Ls-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else if(s==(Ls-1)) {
	spProj5p(tmp, psi[ss+0]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5m(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else {
	spProj5p(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5m(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      }
    }
  });

  this->M5Dtime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::M5Ddag_shift(const FermionField &psi_i, const FermionField &phi_i, FermionField &chi_i,
					   std::vector<Coeff_t> &lower, std::vector<Coeff_t> &diag, std::vector<Coeff_t> &upper,
					   std::vector<Coeff_t> &shift_coeffs)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  int shift_s = (this->pm == 1) ? (Ls-1) : 0; // s-component modified by shift operator
  auto psi = psi_i.View();
  auto phi = phi_i.View();
  auto chi = chi_i.View();

  assert(phi.Checkerboard() == psi.Checkerboard());

  // Flops = 6.0*(Nc*Ns) *Ls*vol
  this->M5Dcalls++;
  this->M5Dtime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{
    chi[ss+Ls-1] = Zero();
    auto tmp = psi[0];
    for(int s=0; s<Ls; s++){
      if(s==0) {
	spProj5p(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5m(tmp, psi[ss+Ls-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else if(s==(Ls-1)) {
	spProj5p(tmp, psi[ss+0]);
	chi[ss+s] = chi[ss+s] + diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5m(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      } else {
	spProj5p(tmp, psi[ss+s+1]);
	chi[ss+s] = diag[s]*phi[ss+s] + upper[s]*tmp;
	spProj5m(tmp, psi[ss+s-1]);
	chi[ss+s] = chi[ss+s] + lower[s]*tmp;
      }
      if(this->pm == 1){ spProj5p(tmp, psi[ss+s]); }
      else{ spProj5m(tmp, psi[ss+s]); }
      chi[ss+shift_s] = chi[ss+shift_s] + shift_coeffs[s]*tmp;
    }
  });

  this->M5Dtime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::MooeeInv(const FermionField &psi_i, FermionField &chi_i)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  auto psi = psi_i.View();
  auto chi = chi_i.View();

  if(this->shift != 0.0){ MooeeInv_shift(psi_i,chi_i); return; }

  this->MooeeInvCalls++;
  this->MooeeInvTime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{

    auto tmp = psi[0];

    // Apply (L^{\prime})^{-1}
    chi[ss] = psi[ss]; // chi[0]=psi[0]
    for(int s=1; s<Ls; s++){
      spProj5p(tmp, chi[ss+s-1]);
      chi[ss+s] = psi[ss+s] - this->lee[s-1]*tmp;
    }

    // L_m^{-1}
    for(int s=0; s<Ls-1; s++){ // Chi[ee] = 1 - sum[s<Ls-1] -leem[s]P_- chi
      spProj5m(tmp, chi[ss+s]);
      chi[ss+Ls-1] = chi[ss+Ls-1] - this->leem[s]*tmp;
    }

    // U_m^{-1} D^{-1}
    for(int s=0; s<Ls-1; s++){ // Chi[s] + 1/d chi[s]
      spProj5p(tmp, chi[ss+Ls-1]);
      chi[ss+s] = (1.0/this->dee[s])*chi[ss+s] - (this->ueem[s]/this->dee[Ls-1])*tmp;
    }
    chi[ss+Ls-1] = (1.0/this->dee[Ls-1])*chi[ss+Ls-1];

    // Apply U^{-1}
    for(int s=Ls-2; s>=0; s--){
      spProj5m(tmp, chi[ss+s+1]);
      chi[ss+s] = chi[ss+s] - this->uee[s]*tmp;
    }
  });

  this->MooeeInvTime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::MooeeInv_shift(const FermionField &psi_i, FermionField &chi_i)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  auto psi = psi_i.View();
  auto chi = chi_i.View();


  this->MooeeInvCalls++;
  this->MooeeInvTime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{

    auto tmp1        = psi[0];
    auto tmp2        = psi[0];
    auto tmp2_spProj = psi[0];

    // Apply (L^{\prime})^{-1} and accumulate MooeeInv_shift_lc[j]*psi[j] in tmp2
    chi[ss] = psi[ss]; // chi[0]=psi[0]
    tmp2 = MooeeInv_shift_lc[0]*psi[ss];
    for(int s=1; s<Ls; s++){
      spProj5p(tmp1, chi[ss+s-1]);
      chi[ss+s] = psi[ss+s] - this->lee[s-1]*tmp1;
      tmp2 = tmp2 + MooeeInv_shift_lc[s]*psi[ss+s];
    }
    if(this->pm == 1){ spProj5p(tmp2_spProj, tmp2);}
    else{ spProj5m(tmp2_spProj, tmp2); }

    // L_m^{-1}
    for(int s=0; s<Ls-1; s++){ // Chi[ee] = 1 - sum[s<Ls-1] -leem[s]P_- chi
      spProj5m(tmp1, chi[ss+s]);
      chi[ss+Ls-1] = chi[ss+Ls-1] - this->leem[s]*tmp1;
    }

    // U_m^{-1} D^{-1}
    for(int s=0; s<Ls-1; s++){ // Chi[s] + 1/d chi[s]
      spProj5p(tmp1, chi[ss+Ls-1]);
      chi[ss+s] = (1.0/this->dee[s])*chi[ss+s] - (this->ueem[s]/this->dee[Ls-1])*tmp1;
    }
    // chi[ss+Ls-1] = (1.0/this->dee[Ls-1])*chi[ss+Ls-1] + MooeeInv_shift_norm[Ls-1]*tmp2_spProj;
    chi[ss+Ls-1] = (1.0/this->dee[Ls-1])*chi[ss+Ls-1];
    spProj5m(tmp1, chi[ss+Ls-1]);
    chi[ss+Ls-1] = chi[ss+Ls-1] + MooeeInv_shift_norm[Ls-1]*tmp2_spProj;

    // Apply U^{-1} and add shift term
    for(int s=Ls-2; s>=0; s--){
      chi[ss+s] = chi[ss+s] - this->uee[s]*tmp1;
      spProj5m(tmp1, chi[ss+s]);
      chi[ss+s] = chi[ss+s] + MooeeInv_shift_norm[s]*tmp2_spProj;
    }
  });

  this->MooeeInvTime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::MooeeInvDag(const FermionField &psi_i, FermionField &chi_i)
{
  if(this->shift != 0.0){ MooeeInvDag_shift(psi_i,chi_i); return; }

  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  int Ls = this->Ls;
  auto psi = psi_i.View();
  auto chi = chi_i.View();

  this->MooeeInvCalls++;
  this->MooeeInvTime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{

    auto tmp = psi[0];

    // Apply (U^{\prime})^{-dag}
    chi[ss] = psi[ss];
    for(int s=1; s<Ls; s++){
      spProj5m(tmp, chi[ss+s-1]);
      chi[ss+s] = psi[ss+s] - this->uee[s-1]*tmp;
    }

    // U_m^{-\dag}
    for(int s=0; s<Ls-1; s++){
      spProj5p(tmp, chi[ss+s]);
      chi[ss+Ls-1] = chi[ss+Ls-1] - this->ueem[s]*tmp;
    }

    // L_m^{-\dag} D^{-dag}
    for(int s=0; s<Ls-1; s++){
      spProj5m(tmp, chi[ss+Ls-1]);
      chi[ss+s] = (1.0/this->dee[s])*chi[ss+s] - (this->leem[s]/this->dee[Ls-1])*tmp;
    }
    chi[ss+Ls-1] = (1.0/this->dee[Ls-1])*chi[ss+Ls-1];

    // Apply L^{-dag}
    for(int s=Ls-2; s>=0; s--){
      spProj5p(tmp, chi[ss+s+1]);
      chi[ss+s] = chi[ss+s] - this->lee[s]*tmp;
    }
  });

  this->MooeeInvTime += usecond();
}

template<class Impl>
void MobiusEOFAFermion<Impl>::MooeeInvDag_shift(const FermionField &psi_i, FermionField &chi_i)
{
  chi_i.Checkerboard() = psi_i.Checkerboard();
  GridBase *grid = psi_i.Grid();
  auto psi = psi_i.View();
  auto chi = chi_i.View();
  int Ls = this->Ls;


  this->MooeeInvCalls++;
  this->MooeeInvTime -= usecond();

  thread_loop( (int ss=0; ss<grid->oSites(); ss+=Ls),{

    auto tmp1        = psi[0];
    auto tmp2        = psi[0];
    auto tmp2_spProj = psi[0];

    // Apply (U^{\prime})^{-dag} and accumulate MooeeInvDag_shift_lc[j]*psi[j] in tmp2
    chi[ss] = psi[ss];
    tmp2 = MooeeInvDag_shift_lc[0]*psi[ss];
    for(int s=1; s<Ls; s++){
      spProj5m(tmp1, chi[ss+s-1]);
      chi[ss+s] = psi[ss+s] - this->uee[s-1]*tmp1;
      tmp2 = tmp2 + MooeeInvDag_shift_lc[s]*psi[ss+s];
    }
    if(this->pm == 1){ spProj5p(tmp2_spProj, tmp2);}
    else{ spProj5m(tmp2_spProj, tmp2); }

    // U_m^{-\dag}
    for(int s=0; s<Ls-1; s++){
      spProj5p(tmp1, chi[ss+s]);
      chi[ss+Ls-1] = chi[ss+Ls-1] - this->ueem[s]*tmp1;
    }

    // L_m^{-\dag} D^{-dag}
    for(int s=0; s<Ls-1; s++){
      spProj5m(tmp1, chi[ss+Ls-1]);
      chi[ss+s] = (1.0/this->dee[s])*chi[ss+s] - (this->leem[s]/this->dee[Ls-1])*tmp1;
    }
    chi[ss+Ls-1] = (1.0/this->dee[Ls-1])*chi[ss+Ls-1];
    spProj5p(tmp1, chi[ss+Ls-1]);
    chi[ss+Ls-1] = chi[ss+Ls-1] + MooeeInvDag_shift_norm[Ls-1]*tmp2_spProj;

    // Apply L^{-dag}
    for(int s=Ls-2; s>=0; s--){
      chi[ss+s] = chi[ss+s] - this->lee[s]*tmp1;
      spProj5p(tmp1, chi[ss+s]);
      chi[ss+s] = chi[ss+s] + MooeeInvDag_shift_norm[s]*tmp2_spProj;
    }
  });

  this->MooeeInvTime += usecond();
}

#ifdef MOBIUS_EOFA_DPERP_CACHE

INSTANTIATE_DPERP_MOBIUS_EOFA(WilsonImplF);
INSTANTIATE_DPERP_MOBIUS_EOFA(WilsonImplD);
INSTANTIATE_DPERP_MOBIUS_EOFA(GparityWilsonImplF);
INSTANTIATE_DPERP_MOBIUS_EOFA(GparityWilsonImplD);
INSTANTIATE_DPERP_MOBIUS_EOFA(ZWilsonImplF);
INSTANTIATE_DPERP_MOBIUS_EOFA(ZWilsonImplD);

INSTANTIATE_DPERP_MOBIUS_EOFA(WilsonImplFH);
INSTANTIATE_DPERP_MOBIUS_EOFA(WilsonImplDF);
INSTANTIATE_DPERP_MOBIUS_EOFA(GparityWilsonImplFH);
INSTANTIATE_DPERP_MOBIUS_EOFA(GparityWilsonImplDF);
INSTANTIATE_DPERP_MOBIUS_EOFA(ZWilsonImplFH);
INSTANTIATE_DPERP_MOBIUS_EOFA(ZWilsonImplDF);

#endif

NAMESPACE_END(Grid);