#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
#include <CGAL/Surface_mesh.h>

#include <CGAL/Polygon_mesh_processing/approximated_centroidal_Voronoi_diagram_remeshing.h>
#include <CGAL/Polygon_mesh_processing/connected_components.h>
#include <CGAL/Polygon_mesh_processing/IO/polygon_mesh_io.h>

#include <iostream>
#include <filesystem>

typedef CGAL::Exact_predicates_inexact_constructions_kernel Kernel;
typedef CGAL::Surface_mesh<Kernel::Point_3> Mesh;

namespace PMP = CGAL::Polygon_mesh_processing;
namespace params = CGAL::parameters;

int main(int argc, char* argv[])
{
  Mesh smesh;
  std::cout << "Seed : " << CGAL::get_default_random().get_seed() << std::endl;

  const std::string filename = (argc > 1) ? argv[1] : CGAL::data_file_path("meshes/fandisk.off");
  const std::string stem = std::filesystem::path(filename).stem().string();
  const std::string extension = std::filesystem::path(filename).extension().string();

  const int nb_clusters = (argc > 2) ? atoi(argv[2]) : 3000;
  const std::string nbc = std::to_string(nb_clusters);

  if (!CGAL::IO::read_polygon_mesh(filename, smesh))
  {
    std::cerr << "Invalid input file." << std::endl;
    return EXIT_FAILURE;
  }

  // Ensure the input is a single connected component.
  // Otherwise, the input must be decomposed.
  auto fcm = smesh.add_property_map<Mesh::Face_index, std::size_t>("fcm", 0).first;
  std::size_t nbcc = PMP::connected_components(smesh, fcm);
  if (nbcc != 1)
  {
    std::cerr << "The input is not a single connected component mesh." << std::endl;
    return EXIT_FAILURE;
  }

  // Uniform Isotropic ACVD
  std::cout << "Uniform Isotropic ACVD ...." << std::endl;
  Mesh acvd_mesh = smesh;
  PMP::approximated_centroidal_Voronoi_diagram_remeshing(acvd_mesh, nb_clusters);
  CGAL::IO::write_polygon_mesh(stem+"_acvd_"+nbc+extension, acvd_mesh);

  // With Post-Processing QEM Optimization
  std::cout << "Uniform Isotropic ACVD with QEM optimization ...." << std::endl;
  Mesh acvd_mesh_qem_pp = smesh;
  PMP::approximated_centroidal_Voronoi_diagram_remeshing(acvd_mesh_qem_pp, nb_clusters, params::use_postprocessing_qem(true));
  CGAL::IO::write_polygon_mesh( stem +"_acvd_qem-pp_"+nbc+extension, acvd_mesh_qem_pp);

  // With QEM Energy Minimization
  std::cout << "Uniform QEM ACVD ...." << std::endl;
  Mesh acvd_mesh_qem = smesh;
  PMP::approximated_centroidal_Voronoi_diagram_remeshing(acvd_mesh_qem, nb_clusters, params::use_qem_based_energy(true));
  CGAL::IO::write_polygon_mesh(stem +"_acvd_qem_"+ std::to_string(nb_clusters) + extension, acvd_mesh_qem);

  // Adaptive Isotropic ACVD
  std::cout << "Adaptive Isotropic ACVD ...." << std::endl;
  const double gradation_factor = 2;
  Mesh adaptive_acvd_mesh = smesh;
  PMP::approximated_centroidal_Voronoi_diagram_remeshing(adaptive_acvd_mesh, nb_clusters, params::gradation_factor(gradation_factor));
  CGAL::IO::write_polygon_mesh(stem +"_acvd_adaptative_"+ std::to_string(nb_clusters) + extension, adaptive_acvd_mesh);

  return 0;
}

