// file: examples/Arrangement_2/example8.C

#include "short_names.h"

#include <CGAL/Homogeneous.h>
#include <CGAL/MP_Float.h>
#include <CGAL/Arr_2_default_dcel.h>
#include <CGAL/Arrangement_2.h>
#include <CGAL/Arr_segment_traits_2.h>

typedef CGAL::MP_Float                                  NT;
typedef CGAL::Homogeneous<NT>                           Kernel;
typedef CGAL::Arr_segment_traits_2<Kernel>              Traits;
typedef Traits::Point_2                                 Point;
typedef Traits::Curve_2                                 Curve;
typedef Traits::X_monotone_curve_2                      X_curve;
typedef CGAL::Arr_2_default_dcel<Traits>                Dcel;
typedef CGAL::Arrangement_2<Dcel,Traits>                Arr_2;

int main()
{
  Arr_2 arr; 

  // Read the segments

  int num_curves;
  int x,y;
  std::cout << "Enter number of segments: " ;
  std::cin >> num_curves;
  while (num_curves--) 
  {
    std::cout << "Enter source coordinates (2 integers): " ;
    std::cin >> x >> y;
    Point s(x, y);

    std::cout << "Enter target coordinates (2 integers): " ;
    std::cin >> x >> y;
    Point t(x, y);

    X_curve seg(s, t);
    arr.insert(seg);
  }

  // Do the ray shooting

  std::cout << "Enter point for ray shooting (2 integers): " ;
  std::cin >> x >> y;
  Point p(x, y);

  Arr_2::Halfedge_handle e = arr.halfedges_begin();
  Arr_2::Locate_type lt;
  e = arr.vertical_ray_shoot(p, lt, true);
  
  // Check the location type
  if (lt == Arr_2::UNBOUNDED_FACE) 
  {
    std::cout << "UNBOUNDED_FACE" << std::endl;
  }
  else 
  {
    std::cout << "The half-edge shot is :" << std::endl;
    std::cout << "(Using homogeneous coordinates <hx, hy, hw> ";
    std::cout << "where <x, y>=<hx/hw, hy/hw>)" << std::endl;
    std::cout << e->source()->point() << " -> " << e->target()->point();
    std::cout << std::endl;
  }

  return 0;  
}