#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <iostream>
#include <exception>
#include <stdexcept>
#include <fstream>

#include "common/Communication.h"
#include "analysis/TwoPhase.h"
#include "analysis/runAnalysis.h"
#include "common/MPI.h"
#include "ProfilerApp.h"
#include "threadpool/thread_pool.h"

/*
 * Simulator for two-phase flow in porous media
 * James E. McClure 2013-2018
 */

using namespace std;

//*************************************************************************
// Implementation of Two-Phase Immiscible LBM 
//*************************************************************************

int main(int argc, char **argv)
{
	// Initialize MPI
    Utilities::startup( argc, argv, true );
	Utilities::MPI comm( MPI_COMM_WORLD );
	int rank = comm.getRank();
	int nprocs = comm.getSize();
	int check=0;
	{ // Limit scope so variables that contain communicators will free before MPI_Finialize
	  int i,j,k,n,Np;
		if (rank == 0){
			printf("********************************************************\n");
			printf("Running DFH/Color LBM	\n");
			printf("********************************************************\n");
		}
		// Initialize compute device
		int device=ScaLBL_SetDevice(rank);
		printf("Using GPU ID %i for rank %i \n",device,rank);
		ScaLBL_DeviceBarrier();
		comm.barrier();

		PROFILE_ENABLE(1);
		//PROFILE_ENABLE_TRACE();
		//PROFILE_ENABLE_MEMORY();
		PROFILE_SYNCHRONIZE();
		PROFILE_START("Main");
		Utilities::setErrorHandlers();

        if ( argc < 2 ) {
            std::cerr << "Invalid number of arguments, no input file specified\n";
            return -1;
        }
        auto filename = argv[1];
        auto db = std::make_shared<Database>( filename );
        auto domain_db = db->getDatabase( "Domain" );
        auto color_db = db->getDatabase( "Color" );
        auto analysis_db = db->getDatabase( "Analysis" );

        if (rank == 0){
            printf("********************************************************\n");
            printf("Running Color LBM    \n");
            printf("********************************************************\n");
        }
        // Initialize compute device
        //        int device=ScaLBL_SetDevice(rank);
        ScaLBL_DeviceBarrier();
        comm.barrier();

        Utilities::setErrorHandlers();

        // Variables that specify the computational domain  
        string FILENAME;

        // Color Model parameters
        int timestepMax = color_db->getScalar<int>( "timestepMax" );
        double tauA = color_db->getWithDefault<double>( "tauA", 1.0 );
        double tauB = color_db->getWithDefault<double>( "tauB", 1.0 );
        double rhoA = color_db->getWithDefault<double>( "rhoA", 1.0 );
        double rhoB = color_db->getWithDefault<double>( "rhoB", 1.0 );
        double Fx = color_db->getVector<double>( "F" )[0];
        double Fy = color_db->getVector<double>( "F" )[1];
        double Fz = color_db->getVector<double>( "F" )[2];
        double alpha = color_db->getWithDefault<double>( "alpha", 0.001 );
        double beta = color_db->getWithDefault<double>( "beta", 0.95 );
        bool Restart = color_db->getWithDefault<bool>( "Restart", false );
        double din = color_db->getWithDefault<double>( "din", 1.0 );
        double dout = color_db->getWithDefault<double>( "dout", 1.0 );;
        double inletA=1.f;
        double inletB=0.f;
        double outletA=0.f;
        double outletB=1.f;
        double flux = 10.f;

        // Read domain values
        auto L = domain_db->getVector<double>( "L" );
        auto size = domain_db->getVector<int>( "n" );
        auto nproc = domain_db->getVector<int>( "nproc" );
        int BoundaryCondition = domain_db->getWithDefault<int>( "BC", 0 );
        int Nx = size[0];
        int Ny = size[1];
        int Nz = size[2];
        int nprocx = nproc[0];
        int nprocy = nproc[1];
        int nprocz = nproc[2];

        int timestep = 6;

        if (BoundaryCondition==4) flux = din*rhoA; // mass flux must adjust for density (see formulation for details

        // Get the rank info
        const RankInfoStruct rank_info(rank,nprocx,nprocy,nprocz);

        comm.barrier();

        if (nprocs != nprocx*nprocy*nprocz){
            printf("nprocx =  %i \n",nprocx);
            printf("nprocy =  %i \n",nprocy);
            printf("nprocz =  %i \n",nprocz);
            INSIST(nprocs == nprocx*nprocy*nprocz,"Fatal error in processor count!");
        }

        if (rank==0){
            printf("********************************************************\n");
            printf("tau (non-wetting) = %f \n", tauA);
            printf("tau (wetting) = %f \n", tauB);
            printf("density (non-wetting) = %f \n", rhoA);
            printf("density (wetting) = %f \n", rhoB);
            printf("alpha = %f \n", alpha);        
            printf("beta = %f \n", beta);
            printf("gamma_{wn} = %f \n", 5.796*alpha);
            printf("Force(x) = %f \n", Fx);
            printf("Force(y) = %f \n", Fy);
            printf("Force(z) = %f \n", Fz);
            printf("Sub-domain size = %i x %i x %i\n",Nx,Ny,Nz);
            printf("Parallel domain size = %i x %i x %i\n",nprocx,nprocy,nprocz);
            if (BoundaryCondition==0) printf("Periodic boundary conditions will applied \n");
            if (BoundaryCondition==1) printf("Pressure boundary conditions will be applied \n");
            if (BoundaryCondition==2) printf("Velocity boundary conditions will be applied \n");
            if (BoundaryCondition==3) printf("Dynamic pressure boundary conditions will be applied \n");
            if (BoundaryCondition==4) printf("Average flux boundary conditions will be applied \n");
            if (!Restart) printf("Initial conditions assigned from phase ID file \n");
            if (Restart) printf("Initial conditions assigned from restart file \n");
            printf("********************************************************\n");
        }

        // Initialized domain and averaging framework for Two-Phase Flow
        bool pBC;
        if (BoundaryCondition==1 || BoundaryCondition==3 || BoundaryCondition == 4)
            pBC=true;
        else
            pBC=false;

        // Full domain used for averaging (do not use mask for analysis)
        auto Dm = std::make_shared<Domain>(domain_db,comm);
        for (int i=0; i<Dm->Nx*Dm->Ny*Dm->Nz; i++) Dm->id[i] = 1;
        auto Averages = std::make_shared<TwoPhase>(Dm);
        //   TwoPhase Averages(Dm);
        Dm->CommInit();

        // Mask that excludes the solid phase
        auto Mask = std::make_shared<Domain>(domain_db,comm);
        comm.barrier();

        Nx+=2; Ny+=2; Nz += 2;
        int N = Nx*Ny*Nz;
        //.......................................................................
        if (rank == 0)    printf("Read input media... \n");
        //.......................................................................
		//.......................................................................
		// Filenames used
		char LocalRankString[8];
		char LocalRankFilename[40];
		char LocalRestartFile[40];
		sprintf(LocalRankString,"%05d",rank);
		sprintf(LocalRankFilename,"%s%s","ID.",LocalRankString);
		sprintf(LocalRestartFile,"%s%s","Restart.",LocalRankString);

		//	printf("Local File Name =  %s \n",LocalRankFilename);
		// .......... READ THE INPUT FILE .......................................
		//	char value;
		auto id = new char[N];
		double sum;
		//...........................................................................
		if (rank == 0) cout << "Setting up bubble..." << endl;
	    double BubbleRadius = 15.5; // Radius of the capillary tube
	    sum=0; Np=0;
	    for (k=0;k<Nz;k++){
	        for (j=0;j<Ny;j++){
	            for (i=0;i<Nx;i++){
	                n = k*Nx*Ny + j*Nz + i;
	                Averages->SDs(i,j,k) = 100.f;
	                // Initialize phase positions field
	                if (Averages->SDs(i,j,k) < 0.0){
	                    id[n] = 0;
	                }
	                else {
	                    sum++;
	                    Np++;
	                }
	            }
	        }
	    }
        // Initialize the bubble
	    for (k=0;k<Nz;k++){
            for (j=0;j<Ny;j++){
                for (i=0;i<Nx;i++){
                    int n = k*Nx*Ny + j*Nz + i;
                    int iglobal= i+(Nx-2)*Dm->iproc();
                    int jglobal= j+(Ny-2)*Dm->jproc();
                    int kglobal= k+(Nz-2)*Dm->kproc();
                    // Initialize phase position field for parallel bubble test
                    if ((iglobal-0.5*(Nx-2)*nprocx)*(iglobal-0.5*(Nx-2)*nprocx)
                            +(jglobal-0.5*(Ny-2)*nprocy)*(jglobal-0.5*(Ny-2)*nprocy)
                            +(kglobal-0.5*(Nz-2)*nprocz)*(kglobal-0.5*(Nz-2)*nprocz) < BubbleRadius*BubbleRadius){
                        id[n] = 2;
                    }
                    else{
                        id[n]=1;
                    }
                }
            }
        }

		//.........................................................
		// don't perform computations at the eight corners
		id[0] = id[Nx-1] = id[(Ny-1)*Nx] = id[(Ny-1)*Nx + Nx-1] = 0;
		id[(Nz-1)*Nx*Ny] = id[(Nz-1)*Nx*Ny+Nx-1] = id[(Nz-1)*Nx*Ny+(Ny-1)*Nx] = id[(Nz-1)*Nx*Ny+(Ny-1)*Nx + Nx-1] = 0;
		//.........................................................

		// Initialize communication structures in averaging domain
		for (i=0; i<Mask->Nx*Mask->Ny*Mask->Nz; i++) Mask->id[i] = id[i];
		Mask->CommInit();
		auto PhaseLabel = new double[N];
		
		//...........................................................................
		if (rank==0)	printf ("Create ScaLBL_Communicator \n");
		// Create a communicator for the device (will use optimized layout)
		auto ScaLBL_Comm = std::make_shared<ScaLBL_Communicator>(Mask);
		
		int Npad=(Np/16 + 2)*16;
		if (rank==0)	printf ("Set up memory efficient layout Npad=%i \n",Npad);
		IntArray Map(Nx,Ny,Nz);
		auto neighborList= new int[18*Npad];
		Np = ScaLBL_Comm->MemoryOptimizedLayoutAA(Map,neighborList,Mask->id.data(),Np,1);
		comm.barrier();

		//...........................................................................
		//				MAIN  VARIABLES ALLOCATED HERE
		//...........................................................................
		// LBM variables
		if (rank==0)	printf ("Allocating distributions \n");
		//......................device distributions.................................
		int dist_mem_size = Np*sizeof(double);
		int neighborSize=18*(Np*sizeof(int));

		int *NeighborList;
		int *dvcMap;
		double *fq, *Aq, *Bq;
		double *Den, *Phi;
		double *SolidPotential;
		double *Velocity;
		double *Gradient;
		double *Pressure;
		
		//...........................................................................
		ScaLBL_AllocateDeviceMemory((void **) &NeighborList, neighborSize);
		ScaLBL_AllocateDeviceMemory((void **) &dvcMap, sizeof(int)*Np);
		ScaLBL_AllocateDeviceMemory((void **) &fq, 19*dist_mem_size);
		ScaLBL_AllocateDeviceMemory((void **) &Aq, 7*dist_mem_size);
		ScaLBL_AllocateDeviceMemory((void **) &Bq, 7*dist_mem_size);
		ScaLBL_AllocateDeviceMemory((void **) &Den, 2*dist_mem_size);
		ScaLBL_AllocateDeviceMemory((void **) &Phi, sizeof(double)*Np);		
		ScaLBL_AllocateDeviceMemory((void **) &Pressure, sizeof(double)*Np);
		ScaLBL_AllocateDeviceMemory((void **) &Velocity, 3*sizeof(double)*Np);
		ScaLBL_AllocateDeviceMemory((void **) &Gradient, 3*sizeof(double)*Np);
		ScaLBL_AllocateDeviceMemory((void **) &SolidPotential, 3*sizeof(double)*Np);
		
		//...........................................................................
		// Update GPU data structures
		if (rank==0)	printf ("Setting up device map and neighbor list \n");
		int *TmpMap;
		TmpMap=new int[Np];
		for (k=1; k<Nz-1; k++){
			for (j=1; j<Ny-1; j++){
				for (i=1; i<Nx-1; i++){
					int idx=Map(i,j,k);
					if (!(idx < 0))
						TmpMap[idx] = k*Nx*Ny+j*Nx+i;
				}
			}
		}
		ScaLBL_CopyToDevice(dvcMap, TmpMap, sizeof(int)*Np);
		ScaLBL_DeviceBarrier();
		delete [] TmpMap;
		
		// Compute the solid interaction potential and copy result to device
		if (rank==0) printf("Computing solid interaction potential \n");
		double *Tmp;
		Tmp=new double[3*Np];
		Averages->UpdateMeshValues(); // this computes the gradient of distance field (among other things)
		double count_wet=0.f;
		double cns,bns,cws,bws;
		cns=bns=bws=cws=1.0;
		for (k=1; k<Nz-1; k++){
			for (j=1; j<Ny-1; j++){
				for (i=1; i<Nx-1; i++){
					int idx=Map(i,j,k);
					int n = k*Nx*Ny+j*Nx+i;
					if (!(idx < 0)){
						double d = Averages->SDs(n);
						double dx = Averages->SDs_x(n);
						double dy = Averages->SDs_y(n);
						double dz = Averages->SDs_z(n);
						double value=cns*exp(-bns*fabs(d))-cws*exp(-bns*fabs(d));
						Tmp[idx] = value*dx;
						Tmp[idx+Np] = value*dy;
						Tmp[idx+2*Np] = value*dz;
						// initialize fluid phases
						if (Mask->id[n] == 1)	PhaseLabel[idx] = 1.0;
						else if (Mask->id[n] == 2){
							PhaseLabel[idx] = -1.0;
							count_wet +=1.0;
						}
						else {
							PhaseLabel[idx] = -1.0;
						}
					}
				}
			}
		}
		printf("wetting fraction=%f \n", count_wet/double(Np));
		ScaLBL_CopyToDevice(SolidPotential, Tmp, 3*sizeof(double)*Np);
		ScaLBL_DeviceBarrier();
		delete [] Tmp;
		
		// copy the neighbor list 
		ScaLBL_CopyToDevice(NeighborList, neighborList, neighborSize);
		// initialize phi based on PhaseLabel (include solid component labels)
		ScaLBL_CopyToDevice(Phi, PhaseLabel, Np*sizeof(double));
		//...........................................................................

		if (rank==0)	printf ("Initializing distributions \n");
		ScaLBL_D3Q19_Init(fq, Np);
		if (rank==0)	printf ("Initializing phase field \n");
		ScaLBL_DFH_Init(Phi, Den, Aq, Bq, 0, ScaLBL_Comm->last_interior, Np);

		//.......................................................................
		// Once phase has been initialized, map solid to account for 'smeared' interface
		//for (i=0; i<N; i++)	Averages.SDs(i) -= (1.0);
		// Make sure the id match for the two domains
		for (i=0; i<N; i++)	Dm->id[i] = Mask->id[i];
		//.......................................................................
		// Finalize setup for averaging domain
		Averages->UpdateSolid();
		//.......................................................................		
		//ScaLBL_D3Q19_Pressure(fq,Pressure,Np);
		//ScaLBL_D3Q19_Momentum(fq,Velocity,Np);
		//...........................................................................
		// Copy the phase indicator field for the earlier timestep
		ScaLBL_DeviceBarrier();
		ScaLBL_CopyToHost(Averages->Phase_tplus.data(),Phi,N*sizeof(double));
		//...........................................................................
		// Copy the data for for the analysis timestep
		//...........................................................................
		// Copy the phase from the GPU -> CPU
		//...........................................................................
		ScaLBL_DeviceBarrier();
		ScaLBL_CopyToHost(Averages->Phase.data(),Phi,N*sizeof(double));
		ScaLBL_Comm->RegularLayout(Map,Pressure,Averages->Press);
		ScaLBL_Comm->RegularLayout(Map,&Velocity[0],Averages->Vel_x);
		ScaLBL_Comm->RegularLayout(Map,&Velocity[Np],Averages->Vel_y);
		ScaLBL_Comm->RegularLayout(Map,&Velocity[2*Np],Averages->Vel_z);
		//...........................................................................

		if (rank==0) printf("********************************************************\n");
		if (rank==0)	printf("No. of timesteps: %i \n", timestepMax);
		double err=1.0;
		double tol=1.0e-6;
		//.......create and start timer............
		double starttime,stoptime,cputime;
		ScaLBL_DeviceBarrier();
		comm.barrier();
		starttime = Utilities::MPI::time();
		//.........................................

		err = 1.0; 	
		if (rank==0) printf("Begin timesteps: error tolerance is %f \n", tol);

		//************ MAIN ITERATION LOOP ***************************************/
		PROFILE_START("Loop");
		//std::shared_ptr<Database> analysis_db;
		runAnalysis analysis(db, rank_info, ScaLBL_Comm, Dm, Np, pBC, Map );
        //analysis.createThreads( analysis_method, 4 );
		while (timestep < timestepMax && err > tol ) {
			//if ( rank==0 ) { printf("Running timestep %i (%i MB)\n",timestep+1,(int)(Utilities::getMemoryUsage()/1048576)); }
			PROFILE_START("Update");
			// *************ODD TIMESTEP*************
			timestep++;
			// Compute the Phase indicator field
			// Read for Aq, Bq happens in this routine (requires communication)
			ScaLBL_Comm->BiSendD3Q7AA(Aq,Bq); //READ FROM NORMAL
			ScaLBL_D3Q7_AAodd_DFH(NeighborList, Aq, Bq, Den, Phi, ScaLBL_Comm->first_interior, ScaLBL_Comm->last_interior, Np);
			ScaLBL_Comm->BiRecvD3Q7AA(Aq,Bq); //WRITE INTO OPPOSITE
			ScaLBL_D3Q7_AAodd_DFH(NeighborList, Aq, Bq, Den, Phi, 0, ScaLBL_Comm->next, Np);

			// compute the gradient 
			ScaLBL_D3Q19_Gradient_DFH(NeighborList, Phi, Gradient, ScaLBL_Comm->first_interior, ScaLBL_Comm->last_interior, Np);
			ScaLBL_Comm->SendHalo(Phi);
			ScaLBL_D3Q19_Gradient_DFH(NeighborList, Phi, Gradient, 0, ScaLBL_Comm->next, Np);
			ScaLBL_Comm->RecvGrad(Phi,Gradient);

			// Perform the collision operation
			ScaLBL_Comm->SendD3Q19AA(fq); //READ FROM NORMAL
			ScaLBL_D3Q19_AAodd_DFH(NeighborList, fq, Aq, Bq, Den, Phi, Gradient, SolidPotential, rhoA, rhoB, tauA, tauB,
					alpha, beta, Fx, Fy, Fz, ScaLBL_Comm->first_interior, ScaLBL_Comm->last_interior, Np);
			ScaLBL_Comm->RecvD3Q19AA(fq); //WRITE INTO OPPOSITE
			// Set BCs
			if (BoundaryCondition > 0){
				ScaLBL_Comm->Color_BC_z(dvcMap, Phi, Den, inletA, inletB);
				ScaLBL_Comm->Color_BC_Z(dvcMap, Phi, Den, outletA, outletB);
			}
			if (BoundaryCondition == 3){
				ScaLBL_Comm->D3Q19_Pressure_BC_z(NeighborList, fq, din, timestep);
				ScaLBL_Comm->D3Q19_Pressure_BC_Z(NeighborList, fq, dout, timestep);
			}
			if (BoundaryCondition == 4){
				din = ScaLBL_Comm->D3Q19_Flux_BC_z(NeighborList, fq, flux, timestep);
				ScaLBL_Comm->D3Q19_Pressure_BC_Z(NeighborList, fq, dout, timestep);
			}
			ScaLBL_D3Q19_AAodd_DFH(NeighborList, fq, Aq, Bq, Den, Phi, Gradient, SolidPotential, rhoA, rhoB, tauA, tauB,
					alpha, beta, Fx, Fy, Fz, 0, ScaLBL_Comm->next, Np);
			ScaLBL_DeviceBarrier(); comm.barrier();

			// *************EVEN TIMESTEP*************
			timestep++;
			// Compute the Phase indicator field
			ScaLBL_Comm->BiSendD3Q7AA(Aq,Bq); //READ FROM NORMAL
			ScaLBL_D3Q7_AAeven_DFH(Aq, Bq, Den, Phi, ScaLBL_Comm->first_interior, ScaLBL_Comm->last_interior, Np);
			ScaLBL_Comm->BiRecvD3Q7AA(Aq,Bq); //WRITE INTO OPPOSITE
			ScaLBL_D3Q7_AAeven_DFH(Aq, Bq, Den, Phi, 0, ScaLBL_Comm->next, Np);

			// compute the gradient 
			ScaLBL_D3Q19_Gradient_DFH(NeighborList, Phi, Gradient, ScaLBL_Comm->first_interior, ScaLBL_Comm->last_interior, Np);
			ScaLBL_Comm->SendHalo(Phi);
			ScaLBL_D3Q19_Gradient_DFH(NeighborList, Phi, Gradient, 0, ScaLBL_Comm->next, Np);
			ScaLBL_Comm->RecvGrad(Phi,Gradient);

			// Perform the collision operation
			ScaLBL_Comm->SendD3Q19AA(fq); //READ FORM NORMAL
			ScaLBL_D3Q19_AAeven_DFH(NeighborList, fq, Aq, Bq, Den, Phi, Gradient, SolidPotential, rhoA, rhoB, tauA, tauB,
					alpha, beta, Fx, Fy, Fz, ScaLBL_Comm->first_interior, ScaLBL_Comm->last_interior, Np);
			ScaLBL_Comm->RecvD3Q19AA(fq); //WRITE INTO OPPOSITE
			// Set boundary conditions
			if (BoundaryCondition > 0){
				ScaLBL_Comm->Color_BC_z(dvcMap, Phi, Den, inletA, inletB);
				ScaLBL_Comm->Color_BC_Z(dvcMap, Phi, Den, outletA, outletB);
			}
			if (BoundaryCondition == 3){
				ScaLBL_Comm->D3Q19_Pressure_BC_z(NeighborList, fq, din, timestep);
				ScaLBL_Comm->D3Q19_Pressure_BC_Z(NeighborList, fq, dout, timestep);
			}
			else if (BoundaryCondition == 4){
				din = ScaLBL_Comm->D3Q19_Flux_BC_z(NeighborList, fq, flux, timestep);
				ScaLBL_Comm->D3Q19_Pressure_BC_Z(NeighborList, fq, dout, timestep);
			}
			ScaLBL_D3Q19_AAeven_DFH(NeighborList, fq, Aq, Bq, Den, Phi, Gradient, SolidPotential, rhoA, rhoB, tauA, tauB,
					alpha, beta, Fx, Fy, Fz,  0, ScaLBL_Comm->next, Np);
			ScaLBL_DeviceBarrier(); comm.barrier();
			//************************************************************************
			comm.barrier();
			PROFILE_STOP("Update");

			// Run the analysis
			analysis.run( timestep, db, *Averages, Phi, Pressure, Velocity, fq, Den );

		}
        analysis.finish();
		PROFILE_STOP("Loop");
		PROFILE_SAVE("lbpm_color_simulator",1);
		//************************************************************************
		ScaLBL_DeviceBarrier();
		comm.barrier();
		stoptime = Utilities::MPI::time();
		if (rank==0) printf("-------------------------------------------------------------------\n");
		// Compute the walltime per timestep
		cputime = (stoptime - starttime)/timestep;
		// Performance obtained from each node
		double MLUPS = double(Np)/cputime/1000000;

		if (rank==0) printf("********************************************************\n");
		if (rank==0) printf("CPU time = %f \n", cputime);
		if (rank==0) printf("Lattice update rate (per core)= %f MLUPS \n", MLUPS);
		MLUPS *= nprocs;
		if (rank==0) printf("Lattice update rate (total)= %f MLUPS \n", MLUPS);
		if (rank==0) printf("********************************************************\n");

		// ************************************************************************
    	
		// Copy back final phase indicator field and convert to regular layout
		DoubleArray PhaseField(Nx,Ny,Nz);
        ScaLBL_Comm->RegularLayout(Map,Phi,PhaseField);
		sprintf(LocalRankFilename,"Phase.raw");
		auto OUTFILE = fopen(LocalRankFilename,"wb");
    	fwrite(PhaseField.data(),8,N,OUTFILE);
    	fclose(OUTFILE);
    	
		DoubleArray Cx(Nx,Ny,Nz);
		DoubleArray Cy(Nx,Ny,Nz);
		DoubleArray Cz(Nx,Ny,Nz);
		DoubleArray GradNorm(Nx,Ny,Nz);
        ScaLBL_Comm->RegularLayout(Map,&Gradient[0],Cx);
        ScaLBL_Comm->RegularLayout(Map,&Gradient[Np],Cy);
        ScaLBL_Comm->RegularLayout(Map,&Gradient[2*Np],Cz);
		for (k=1; k<Nz-1; k++){
			for (j=1; j<Ny-1; j++){
				for (i=1; i<Nx-1; i++){
					GradNorm(i,j,k) = Cx(i,j,k)*Cx(i,j,k) + Cy(i,j,k)*Cy(i,j,k) + Cz(i,j,k)*Cz(i,j,k);
				}
			}
		}
		sprintf(LocalRankFilename,"Gradient.raw");
		auto GFILE = fopen(LocalRankFilename,"wb");
    	fwrite(GradNorm.data(),8,N,GFILE);
    	fclose(GFILE);
    	
		DoubleArray Rho1(Nx,Ny,Nz);
		DoubleArray Rho2(Nx,Ny,Nz);
        ScaLBL_Comm->RegularLayout(Map,&Den[0],Rho1);
        ScaLBL_Comm->RegularLayout(Map,&Den[Np],Rho2);
		sprintf(LocalRankFilename,"Rho1.raw");
		auto RFILE1 = fopen(LocalRankFilename,"wb");
    	fwrite(Rho1.data(),8,N,RFILE1);
    	fclose(RFILE1);
		sprintf(LocalRankFilename,"Rho2.raw");
		auto RFILE2 = fopen(LocalRankFilename,"wb");
    	fwrite(Rho2.data(),8,N,RFILE2);
    	fclose(RFILE2);
    	
		PROFILE_STOP("Main");
		PROFILE_SAVE("lbpm_color_simulator",1);
		// ****************************************************
		comm.barrier();
	} // Limit scope so variables that contain communicators will free before MPI_Finialize
    Utilities::shutdown();
	return check;
}