#include <gudhi/Rips_complex.h>
// to construct Rips_complex from a fvecs file of points
#include <gudhi/Simplex_tree.h>
#include <gudhi/Fake_simplex_tree.h>
#include <gudhi/distance_functions.h>
#include <gudhi/Points_fvecs_reader.h>

#include <CGAL/Epick_d.h>

#include <iostream>
#include <string>
#include <vector>

void usage(int nbArgs, char * const progName) {
  std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
  std::cerr << "Usage: " << progName << " filename.fvecs threshold dim_max [ouput_file.txt]\n";
  std::cerr << "       i.e.: " << progName << " ../../data/points/alphacomplexdoc.fvecs 60.0\n";
  exit(-1);  // ----- >>
}

int main(int argc, char **argv) {
  if ((argc != 4) && (argc != 5)) usage(argc, (argv[0] - 1));

  std::string file_name(argv[1]);
  double threshold = atof(argv[2]);
  int dim_max = atoi(argv[3]);

  // Type definitions
  using K = CGAL::Epick_d<CGAL::Dynamic_dimension_tag>;
  using Point = typename K::Point_d;
  //using Simplex_tree = Gudhi::Simplex_tree<>;
  using Simplex_tree = Gudhi::Fake_simplex_tree;
  using Filtration_value = Simplex_tree::Filtration_value;
  using Rips_complex = Gudhi::rips_complex::Rips_complex<Filtration_value>;
  using Point_vector = std::vector<Point>;

  // ----------------------------------------------------------------------------
  // Init of a Rips complex from an fvecs file
  // ----------------------------------------------------------------------------
  Point_vector point_vector;
  Gudhi::load_points_from_fvecs_file<K>(file_name, std::back_insert_iterator< Point_vector >(point_vector));

  Rips_complex rips_complex_from_file(point_vector, threshold, Gudhi::Euclidean_distance());

  std::streambuf* streambufffer;
  std::ofstream ouput_file_stream;

  if (argc == 5) {
    ouput_file_stream.open(std::string(argv[4]));
    streambufffer = ouput_file_stream.rdbuf();
  } else {
    streambufffer = std::cout.rdbuf();
  }

  Simplex_tree stree;
  rips_complex_from_file.create_complex(stree, dim_max);
  std::ostream output_stream(streambufffer);

  // ----------------------------------------------------------------------------
  // Display information about the Rips complex
  // ----------------------------------------------------------------------------
  output_stream << "Rips complex is of dimension " << stree.dimension() <<
                   " - " << stree.num_simplices() << " simplices." << std::endl;

  ouput_file_stream.close();
  return 0;
}