// Copyright (c) 2015 GeometryFactory
//
// This file is part of CGAL (www.cgal.org)
//
// $URL$
// $Id$
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
//
// Author(s)     : Mael Rouxel-Labbé

#ifndef CGAL_STREAM_SUPPORT_HELPERS_H
#define CGAL_STREAM_SUPPORT_HELPERS_H

#include <CGAL/array.h>
#include <CGAL/assertions.h>
#include <CGAL/Container_helper.h>
#include <CGAL/Has_member.h>
#include <CGAL/Point_3.h>
#include <CGAL/is_iterator.h>

#include <boost/mpl/logical.hpp>
#include <boost/mpl/has_xxx.hpp>

namespace CGAL {
namespace IO {
namespace internal {

// Ideally this should be a std::is_constructible(double, double, double) but boost::is_constructible
// is not safe to use without CXX11
template <typename Kernel>
void fill_point(const double x, const double y, const double z, const double w, CGAL::Point_3<Kernel>& pt)
{
  pt = CGAL::Point_3<Kernel>(x, y, z, w);
}

template <typename Point_3>
void fill_point(const double x, const double y, const double z, const double w, Point_3& pt)
{
  // just in case something weirder than arrays or CGAL points are used as points...
  CGAL::internal::resize(pt, 3);

  pt[0] = x/w; pt[1] = y/w; pt[2] = z/w;
}

// Functions like 'write_OFF' can take :
// - write_OFF(stream, point_set)
// - write_OFF(stream, pointrange)
// - write_OFF(stream, polygon_mesh)
// so a way to distinguish is needed
BOOST_MPL_HAS_XXX_TRAIT_DEF(Point_set)

template <typename T>
struct is_Point_set_3 : has_Point_set<T> { };

// Point_set_3 also functions as range, so it needs to be excluded
template <typename T>
struct is_Range
  : public boost::mpl::and_<
             boost::has_range_const_iterator<T>,
             boost::mpl::not_<is_Point_set_3<T> > >
{ };

// For polygon meshes
template <typename T>
struct is_Point_set_or_Range_or_Iterator
  : public boost::mpl::or_<is_Point_set_3<T>, is_Range<T>, is_iterator<T> >
{ };

} // end namespace internal
} // end namespace IO
} // namespace CGAL

#endif // CGAL_STREAM_SUPPORT_HELPERS_H