// ===================================================================================
// Copyright ScalFmm 2011 INRIA, Olivier Coulaud, Berenger Bramas, Matthias Messner
// olivier.coulaud@inria.fr, berenger.bramas@inria.fr
// This software is a computer program whose purpose is to compute the FMM.
//
// This software is governed by the CeCILL-C and LGPL licenses and
// abiding by the rules of distribution of free software.  
// 
// 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 and CeCILL-C Licenses for more details.
// "http://www.cecill.info". 
// "http://www.gnu.org/licenses".
// ===================================================================================

#include <iostream>

#include <cstdio>
#include <cstdlib>

#include "../../Src/Utils/FTic.hpp"
#include "../../Src/Utils/FParameters.hpp"

#include "../../Src/Containers/FOctree.hpp"
#include "../../Src/Containers/FVector.hpp"

#include "../../Src/Core/FFmmAlgorithm.hpp"

#include "../../Src/Kernels/Spherical/FSphericalKernel.hpp"
#include "../../Src/Kernels/Spherical/FSphericalCell.hpp"
#include "../../Src/Components/FSimpleLeaf.hpp"

#include "../../Src/Files/FFmaGenericLoader.hpp"
#include "../../Src/Kernels/P2P/FP2PParticleContainer.hpp"

/** This program show an example of use of
  * the fmm basic algo
  * it also check that each particles is little or longer
  * related that each other
  */


// Simply create particles and try the kernels
int main(int argc, char ** argv){
    typedef FSphericalCell                 CellClass;
    typedef FP2PParticleContainer<>     ContainerClass;

    typedef FSimpleLeaf< ContainerClass >                             LeafClass;
    typedef FOctree< CellClass, ContainerClass , LeafClass >  OctreeClass;
    typedef FSphericalKernel< CellClass, ContainerClass >      KernelClass;

    typedef FFmmAlgorithm<OctreeClass, CellClass, ContainerClass, KernelClass, LeafClass > FmmClass;
    //
    ///////////////////////What we do/////////////////////////////
    std::cout << ">> This executable has to be used to test Spherical algorithm.\n";
    //////////////////////////////////////////////////////////////
    const int DevP           = FParameters::getValue(argc,argv,"-p", 8);
    const int NbLevels       = FParameters::getValue(argc,argv,"-depth", 3);
    const int SizeSubLevels  = FParameters::getValue(argc,argv,"-subdepth", 3);
    FTic counter;
    const char* const filename = FParameters::getStr(argc,argv,"-f", "../Data/test20k.fma");

    std::cout << "Openening : " << filename << "\n";

    FFmaGenericLoader loader(filename);
    if(!loader.isOpen()){
        std::cout << "Loader Error, " << filename << " is missing\n";
        return 1;
    }

    // -----------------------------------------------------
    CellClass::Init(DevP);
    OctreeClass tree(NbLevels, SizeSubLevels, loader.getBoxWidth(), loader.getCenterOfBox());

    // -----------------------------------------------------

    std::cout << "Creating & Inserting " << loader.getNumberOfParticles() << " particles ..." << std::endl;
    std::cout << "\tHeight : " << NbLevels << " \t sub-height : " << SizeSubLevels << std::endl;
    counter.tic();

    for(int idxPart = 0 ; idxPart < loader.getNumberOfParticles() ; ++idxPart){
        FPoint particlePosition;
        FReal physicalValue;
        loader.fillParticle(&particlePosition,&physicalValue);
        tree.insert(particlePosition, physicalValue );
    }

    counter.tac();
    std::cout << "Done  " << "(@Creating and Inserting Particles = " << counter.elapsed() << "s)." << std::endl;

    // -----------------------------------------------------

    std::cout << "Create kernel ..." << std::endl;
    counter.tic();

    KernelClass kernels(DevP, NbLevels, loader.getBoxWidth(), loader.getCenterOfBox());

    counter.tac();
    std::cout << "Done  " << " in " << counter.elapsed() << "s)." << std::endl;

    // -----------------------------------------------------

    std::cout << "Working on particles ..." << std::endl;

    FmmClass algo(&tree,&kernels);
    counter.tic();
    algo.execute();
    counter.tac();

    std::cout << "Done  " << "(@Algorithm = " << counter.elapsed() << "s)." << std::endl;

    { // get sum forces&potential
        FReal potential = 0;
        FReal fx = 0.0, fy = 0.0, fz = 0.0;

        tree.forEachLeaf([&](LeafClass* leaf){
            const FReal*const potentials = leaf->getTargets()->getPotentials();
            const FReal*const forcesX = leaf->getTargets()->getForcesX();
            const FReal*const forcesY = leaf->getTargets()->getForcesY();
            const FReal*const forcesZ = leaf->getTargets()->getForcesZ();
            const int nbParticlesInLeaf = leaf->getTargets()->getNbParticles();

            for(int idxPart = 0 ; idxPart < nbParticlesInLeaf ; ++idxPart){
                potential += potentials[idxPart];
                fx += forcesX[idxPart];
                fy += forcesY[idxPart];
                fz += forcesZ[idxPart];
            }
        });

        std::cout << "Foces Sum  x = " << fx << " y = " << fy << " z = " << fz << std::endl;
        std::cout << "Potential = " << potential << std::endl;
    }

    // -----------------------------------------------------


    return 0;
}