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

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

Source file: ./tests/Test_hmc_EODWFRatio.cc

Copyright (C) 2015-2016

Author: Peter Boyle <pabobyle@ph.ed.ac.uk>
Author: Guido Cossu <guido.cossu@ed.ac.uk>

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/Grid.h>

int main(int argc, char **argv) {
  using namespace Grid;

  Grid_init(&argc, &argv);
  int threads = GridThread::GetThreads();

   // Typedefs to simplify notation
  typedef WilsonImplR FermionImplPolicy;
  typedef MobiusFermionD FermionAction;
  typedef typename FermionAction::FermionField FermionField;

  typedef Grid::XmlReader       Serialiser;

  //::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
  IntegratorParameters MD;
  //  typedef GenericHMCRunner<LeapFrog> HMCWrapper;
  //  MD.name    = std::string("Leap Frog");
  //  typedef GenericHMCRunner<ForceGradient> HMCWrapper;
  //  MD.name    = std::string("Force Gradient");
  typedef GenericHMCRunner<MinimumNorm2> HMCWrapper;
  MD.name    = std::string("MinimumNorm2");
  MD.MDsteps =  6;
  MD.trajL   = 1.0;

  HMCparameters HMCparams;
  HMCparams.StartTrajectory  = 1077;
  HMCparams.Trajectories     = 1;
  HMCparams.NoMetropolisUntil=  0;
  // "[HotStart, ColdStart, TepidStart, CheckpointStart]\n";
  //  HMCparams.StartingType     =std::string("ColdStart");
  HMCparams.StartingType     =std::string("CheckpointStart");
  HMCparams.MD = MD;
  HMCWrapper TheHMC(HMCparams);

  // Grid from the command line arguments --grid and --mpi
  TheHMC.Resources.AddFourDimGrid("gauge"); // use default simd lanes decomposition

  CheckpointerParameters CPparams;
  CPparams.config_prefix = "ckpoint_DDHMC_lat";
  CPparams.rng_prefix    = "ckpoint_DDHMC_rng";
  CPparams.saveInterval  = 1;
  CPparams.format        = "IEEE64BIG";
  TheHMC.Resources.LoadNerscCheckpointer(CPparams);

  RNGModuleParameters RNGpar;
  RNGpar.serial_seeds = "1 2 3 4 5";
  RNGpar.parallel_seeds = "6 7 8 9 10";
  TheHMC.Resources.SetRNGSeeds(RNGpar);

  // Construct observables
  // here there is too much indirection
  typedef PlaquetteMod<HMCWrapper::ImplPolicy> PlaqObs;
  TheHMC.Resources.AddObservable<PlaqObs>();
  //////////////////////////////////////////////

  const int Ls      = 12;
  RealD M5  = 1.8;
  RealD b   = 1.5;
  RealD c   = 0.5;
  //  Real beta         = 2.31;
  //  Real light_mass   = 5.4e-4;
  Real beta         = 2.13;
  Real light_mass   = 7.8e-4;
  Real strange_mass = 0.02132;
  Real pv_mass      = 1.0;
  //  std::vector<Real> hasenbusch({ light_mass, 3.8e-3, 0.0145, 0.045, 0.108, 0.25, 0.51 , pv_mass });
  std::vector<Real> hasenbusch({ light_mass, 0.0145, 0.045, 0.108, 0.25, 0.51 , pv_mass });

  // FIXME:
  // Same in MC and MD
  // Need to mix precision too
  OneFlavourRationalParams SFRp; // Strange
  SFRp.lo       = 4.0e-3;
  SFRp.hi       = 90.0;
  SFRp.MaxIter  = 60000;
  SFRp.tolerance= 1.0e-8;
  SFRp.mdtolerance= 1.0e-4;
  SFRp.degree   = 12;
  SFRp.precision= 50;
  SFRp.BoundsCheckFreq=0;

  OneFlavourRationalParams OFRp; // Up/down
  OFRp.lo       = 2.0e-5;
  OFRp.hi       = 90.0;
  OFRp.MaxIter  = 60000;
  OFRp.tolerance= 1.0e-7;
  OFRp.mdtolerance= 1.0e-4;
  //  OFRp.degree   = 20; converges
  //  OFRp.degree   = 16;
  OFRp.degree   = 12;
  OFRp.precision= 80;
  OFRp.BoundsCheckFreq=0;

  auto GridPtr   = TheHMC.Resources.GetCartesian();
  auto GridRBPtr = TheHMC.Resources.GetRBCartesian();

  ////////////////////////////////////////////////////////////////
  // Domain decomposed
  ////////////////////////////////////////////////////////////////
  Coordinate latt4  = GridPtr->GlobalDimensions();
  Coordinate mpi    = GridPtr->ProcessorGrid();
  Coordinate shm;

  GlobalSharedMemory::GetShmDims(mpi,shm);
  
  Coordinate CommDim(Nd);
  for(int d=0;d<Nd;d++) CommDim[d]= (mpi[d]/shm[d])>1 ? 1 : 0;

  Coordinate NonDirichlet(Nd+1,0);
  Coordinate Dirichlet(Nd+1,0);
  Dirichlet[1] = CommDim[0]*latt4[0]/mpi[0] * shm[0];
  Dirichlet[2] = CommDim[1]*latt4[1]/mpi[1] * shm[1];
  Dirichlet[3] = CommDim[2]*latt4[2]/mpi[2] * shm[2];
  Dirichlet[4] = CommDim[3]*latt4[3]/mpi[3] * shm[3];

  Coordinate Block4(Nd);
  //  Block4[0] = Dirichlet[1];
  //  Block4[1] = Dirichlet[2];
  //  Block4[2] = Dirichlet[3];
  Block4[0] = 0;
  Block4[1] = 0;
  Block4[2] = 0;
  Block4[3] = Dirichlet[4];

  int Width=3;
  TheHMC.Resources.SetMomentumFilter(new DDHMCFilter<WilsonImplR::Field>(Block4,Width));

  //////////////////////////
  // Fermion Grid
  //////////////////////////
  auto FGrid     = SpaceTimeGrid::makeFiveDimGrid(Ls,GridPtr);
  auto FrbGrid   = SpaceTimeGrid::makeFiveDimRedBlackGrid(Ls,GridPtr);

  IwasakiGaugeActionR GaugeAction(beta);

  // temporarily need a gauge field
  LatticeGaugeField U(GridPtr);

  std::cout << GridLogMessage << " Running the HMC "<< std::endl;
  TheHMC.ReadCommandLine(argc,argv);  // params on CML or from param file
  TheHMC.initializeGaugeFieldAndRNGs(U);


  // These lines are unecessary if BC are all periodic
  std::vector<Complex> boundary = {1,1,1,-1};
  FermionAction::ImplParams Params(boundary);
  Params.dirichlet=NonDirichlet;
  FermionAction::ImplParams ParamsDir(boundary);
  ParamsDir.dirichlet=Dirichlet;

  //  double StoppingCondition = 1e-14;
  //  double MDStoppingCondition = 1e-9;
  double StoppingCondition = 1e-8;
  double MDStoppingCondition = 1e-6;
  double MaxCGIterations = 300000;
  ConjugateGradient<FermionField>  CG(StoppingCondition,MaxCGIterations);
  ConjugateGradient<FermionField>  MDCG(MDStoppingCondition,MaxCGIterations);

  ////////////////////////////////////
  // Collect actions
  ////////////////////////////////////
  ActionLevel<HMCWrapper::Field> Level1(1);
  ActionLevel<HMCWrapper::Field> Level2(4);
  ActionLevel<HMCWrapper::Field> Level3(8);

  ////////////////////////////////////
  // Strange action
  ////////////////////////////////////
  FermionAction StrangeOp (U,*FGrid,*FrbGrid,*GridPtr,*GridRBPtr,strange_mass,M5,b,c, Params);
  FermionAction StrangePauliVillarsOp(U,*FGrid,*FrbGrid,*GridPtr,*GridRBPtr,pv_mass,  M5,b,c, Params);

  FermionAction StrangeOpDir (U,*FGrid,*FrbGrid,*GridPtr,*GridRBPtr,strange_mass,M5,b,c, ParamsDir);
  FermionAction StrangePauliVillarsOpDir(U,*FGrid,*FrbGrid,*GridPtr,*GridRBPtr,pv_mass,  M5,b,c, ParamsDir);
  
  OneFlavourEvenOddRatioRationalPseudoFermionAction<FermionImplPolicy> StrangePseudoFermionBdy(StrangeOpDir,StrangeOp,SFRp);
  OneFlavourEvenOddRatioRationalPseudoFermionAction<FermionImplPolicy> StrangePseudoFermionLocal(StrangePauliVillarsOpDir,StrangeOpDir,SFRp);
  OneFlavourEvenOddRatioRationalPseudoFermionAction<FermionImplPolicy> StrangePseudoFermionPVBdy(StrangePauliVillarsOp,StrangePauliVillarsOpDir,SFRp);
  Level1.push_back(&StrangePseudoFermionBdy);
  Level2.push_back(&StrangePseudoFermionLocal);
  Level1.push_back(&StrangePseudoFermionPVBdy);

  ////////////////////////////////////
  // up down action
  ////////////////////////////////////
  std::vector<Real> light_den;
  std::vector<Real> light_num;
  std::vector<int> dirichlet_den;
  std::vector<int> dirichlet_num;

  int n_hasenbusch = hasenbusch.size();
  light_den.push_back(light_mass);  dirichlet_den.push_back(0);
  for(int h=0;h<n_hasenbusch;h++){
    light_den.push_back(hasenbusch[h]); dirichlet_den.push_back(1);
  }

  for(int h=0;h<n_hasenbusch;h++){
    light_num.push_back(hasenbusch[h]); dirichlet_num.push_back(1);
  }
  light_num.push_back(pv_mass);  dirichlet_num.push_back(0);

  std::vector<FermionAction *> Numerators;
  std::vector<FermionAction *> Denominators;
  std::vector<TwoFlavourEvenOddRatioPseudoFermionAction<FermionImplPolicy> *> Quotients;
  std::vector<OneFlavourEvenOddRatioRationalPseudoFermionAction<FermionImplPolicy> *> Bdys;
  
  for(int h=0;h<n_hasenbusch+1;h++){
    std::cout << GridLogMessage
	      << " 2f quotient Action ";
    std::cout << "det D("<<light_den[h]<<")";
    if ( dirichlet_den[h] ) std::cout << "^dirichlet    ";
    std::cout << "/ det D("<<light_num[h]<<")";
    if ( dirichlet_num[h] ) std::cout << "^dirichlet    ";
    std::cout << std::endl;

    FermionAction::ImplParams ParamsNum(boundary);
    FermionAction::ImplParams ParamsDen(boundary);
    
    if ( dirichlet_num[h]==1) ParamsNum.dirichlet = Dirichlet;
    else                      ParamsNum.dirichlet = NonDirichlet;
    Numerators.push_back  (new FermionAction(U,*FGrid,*FrbGrid,*GridPtr,*GridRBPtr,light_num[h],M5,b,c, ParamsNum));

    if ( dirichlet_den[h]==1) ParamsDen.dirichlet = Dirichlet;
    else                      ParamsDen.dirichlet = NonDirichlet;
    Denominators.push_back(new FermionAction(U,*FGrid,*FrbGrid,*GridPtr,*GridRBPtr,light_den[h],M5,b,c, ParamsDen));
    
    if(h!=0) {
      Quotients.push_back   (new TwoFlavourEvenOddRatioPseudoFermionAction<FermionImplPolicy>(*Numerators[h],*Denominators[h],MDCG,CG));
    } else {
      Bdys.push_back( new OneFlavourEvenOddRatioRationalPseudoFermionAction<FermionImplPolicy>(*Numerators[h],*Denominators[h],OFRp));
      Bdys.push_back( new OneFlavourEvenOddRatioRationalPseudoFermionAction<FermionImplPolicy>(*Numerators[h],*Denominators[h],OFRp));
    }
  }

  int nquo=Quotients.size();
  Level1.push_back(Bdys[0]);
  Level1.push_back(Bdys[1]);
  for(int h=0;h<nquo-1;h++){
    Level2.push_back(Quotients[h]);
  }
  Level2.push_back(Quotients[nquo-1]);

  /////////////////////////////////////////////////////////////
  // Gauge action
  /////////////////////////////////////////////////////////////
  Level3.push_back(&GaugeAction);
  TheHMC.TheAction.push_back(Level1);
  TheHMC.TheAction.push_back(Level2);
  TheHMC.TheAction.push_back(Level3);
  std::cout << GridLogMessage << " Action complete "<< std::endl;
  /////////////////////////////////////////////////////////////

  if(1){
    // TODO:
    // i)  Break high bound, how rapidly does it break? Tune this test.
    // ii) Break low bound, how rapidly?
    // iii) Run lanczos
    // iv)  Have CG return spectral range estimate
    FermionField vec(StrangeOp.FermionRedBlackGrid());
    FermionField res(StrangeOp.FermionRedBlackGrid());
    vec = 1; // Fill with any old junk

    std::cout << "Bounds check on strange operator mass "<< StrangeOp.Mass()<<std::endl;
    SchurDifferentiableOperator<FermionImplPolicy> SdagS(StrangeOp);
    HighBoundCheck(SdagS,vec,SFRp.hi);
    ChebyBoundsCheck(SdagS,vec,SFRp.lo,SFRp.hi);
    std::cout << "Strange inversion"<<std::endl;
    res=Zero();
    //    MDCG(SdagS,vec,res);


    std::cout << "Bounds check on light quark operator mass "<< Denominators[0]->Mass() <<std::endl;
    SchurDifferentiableOperator<FermionImplPolicy> UdagU(*Denominators[0]);
    HighBoundCheck(UdagU,vec,OFRp.hi);
    ChebyBoundsCheck(UdagU,vec,OFRp.lo,OFRp.hi);
    std::cout << "light inversion"<<std::endl;
    res=Zero();
    //    MDCG(UdagU,vec,res);


    std::cout << "Bounds check on strange dirichlet operator mass "<< StrangeOpDir.Mass()<<std::endl;
    SchurDifferentiableOperator<FermionImplPolicy> SddagSd(StrangeOpDir);
    HighBoundCheck(SddagSd,vec,OFRp.hi);
    ChebyBoundsCheck(SddagSd,vec,OFRp.lo,OFRp.hi);
    std::cout << "strange dirichlet inversion"<<std::endl;
    res=Zero();
    //    MDCG(SddagSd,vec,res);

    std::cout << "Bounds check on light dirichlet operator mass "<< Numerators[0]->Mass()<<std::endl;
    SchurDifferentiableOperator<FermionImplPolicy> UddagUd(*Numerators[0]);
    HighBoundCheck(UddagUd,vec,OFRp.hi);
    ChebyBoundsCheck(UddagUd,vec,OFRp.lo,OFRp.hi);
    std::cout << "light dirichlet inversion"<<std::endl;
    res=Zero();
    //MDCG(UddagUd,vec,res);

    
    auto grid4= GridPtr;
    auto rbgrid4= GridRBPtr;
    auto rbgrid = StrangeOp.FermionRedBlackGrid();
    auto grid = StrangeOp.FermionGrid();
    if(1){
    const int Nstop = 5;
    const int Nk = 20;
    const int Np = 20;
    const int Nm = Nk+Np;
    const int MaxIt= 10000;
    int Nconv;
    RealD resid = 1.0e-5;
    if(0)
    {
      int order = 501;
      RealD bound = 5.0e-4;
      std::cout << GridLogMessage << " Lanczos for dirichlet bound " << bound<<" order "<< order<<std::endl;
      Chebyshev<FermionField> Cheby(bound,90.,order);
      FunctionHermOp<FermionField> OpCheby(Cheby,UddagUd);
      PlainHermOp<FermionField> Op     (UddagUd);
      ImplicitlyRestartedLanczos<FermionField> IRL(OpCheby,Op,Nstop,Nk,Nm,resid,MaxIt);
      std::vector<RealD>          eval(Nm);
      std::vector<FermionField> evec(Nm,rbgrid);
      FermionField    src(rbgrid);src = 1.0;
      IRL.calc(eval,evec,src,Nconv);
      
      FermionField tmp(rbgrid);
      FermionField ftmp(grid);
      FermionField ftmp4(grid4);
      for(int ev=0;ev<evec.size();ev++){
	Gamma GT(Gamma::Algebra::GammaT);
	std::cout << " evec " << ev << std::endl;
	tmp = evec[ev] + GT*evec[ev];
	DumpSliceNorm(" 1+gammaT ",tmp,Nd);
	tmp = evec[ev] - GT*evec[ev];
	DumpSliceNorm(" 1-gammaT ",tmp,Nd);
      }
      for(int e=0;e<10;e++){
	std::cout << " Dirichlet evec "<<e<<std::endl;
	tmp = evec[e];
	for(int s=0;s<Ls;s++){
	  ftmp=Zero();
	  setCheckerboard(ftmp,tmp);
	  ExtractSlice(ftmp4,ftmp,s,0);
	  std::cout << "s-slice "<<s<< " evec[0] " << std::endl;
	  DumpSliceNorm(" s-slice ",ftmp4,Nd-1);
	}
      }
    }
    if(1)
    {
      int order = 2001;
      RealD bound = 6.0e-5;
      std::cout << GridLogMessage << " Lanczos for full operator  bound " << bound<<" order "<< order<<std::endl;
      Chebyshev<FermionField> Cheby(bound,90.,order);
      FunctionHermOp<FermionField> OpCheby(Cheby,UdagU);
      PlainHermOp<FermionField> Op     (UdagU);
      ImplicitlyRestartedLanczos<FermionField> IRL(OpCheby,Op,Nstop,Nk,Nm,resid,MaxIt);
      std::vector<RealD>          eval(Nm);
      std::vector<FermionField> evec(Nm,rbgrid);
      FermionField    src(rbgrid); src = 1.0;
      IRL.calc(eval,evec,src,Nconv);

      FermionField tmp(rbgrid);
      FermionField ftmp(grid);
      FermionField ftmp4(grid4);
      for(int e=0;e<evec.size();e++){
	std::cout << " Full evec "<<e<<std::endl;
	tmp = evec[e];
	for(int s=0;s<Ls;s++){
	  ftmp=Zero();
	  setCheckerboard(ftmp,tmp);
	  ExtractSlice(ftmp4,ftmp,s,0);
	  std::cout << "s-slice "<<s<< " evec[0] " << std::endl;
	  DumpSliceNorm(" s-slice ",ftmp4,Nd-1);
	}
      }

    }
    Grid_finalize();
    std::cout << " All done "<<std::endl;
    exit(EXIT_SUCCESS);
    }
  }

  TheHMC.Run();  // no smearing

  Grid_finalize();
} // main