#ifndef CGAL_SURFACE_MESH_SEGMENTATION_MESH_SEGMENTATION_H
#define CGAL_SURFACE_MESH_SEGMENTATION_MESH_SEGMENTATION_H

/**
 * @file mesh_segmentation.h
 * @brief The API which contains free template functions for SDF computation and mesh segmentation.
 */
#include <CGAL/internal/Surface_mesh_segmentation/Surface_mesh_segmentation.h>
#include <boost/config.hpp>

namespace CGAL
{


/// @cond SKIP_IN_MANUAL
template <bool Fast_sdf_calculation_mode, class Polyhedron,
         class SDFPropertyMap, class GeomTraits
#ifndef BOOST_NO_FUNCTION_TEMPLATE_DEFAULT_ARGS
         = typename Polyhedron::Traits
#endif
         >
std::pair<double, double>
compute_sdf_values( const Polyhedron& polyhedron,
                    SDFPropertyMap sdf_values,
                    double cone_angle = 2.0 / 3.0 * CGAL_PI,
                    int number_of_rays = 25,
                    bool postprocess = true,
                    GeomTraits traits = GeomTraits())
{
  internal::Surface_mesh_segmentation<Polyhedron, GeomTraits, Fast_sdf_calculation_mode>
  algorithm(polyhedron, traits);
  return algorithm.calculate_sdf_values(cone_angle, number_of_rays, sdf_values,
                                        postprocess);
}
/// @endcond

/*!
 * \ingroup PkgSurfaceSegmentation
 * @brief Function computing the Shape Diameter Function over a surface mesh.
 *
 * This function implements the Shape Diameter Function (SDF) as described in \cgalCite{shapira2008consistent}.
 * It is possible to compute raw SDF values (without post-processing). In such a case,
 * -1 is used to indicate when no SDF value could be computed for a facet.
 *
 * @pre @a polyhedron.is_pure_triangle()
 *
 * @tparam Polyhedron a %CGAL polyhedron
 * @tparam SDFPropertyMap  a `ReadWritePropertyMap` with `Polyhedron::Facet_const_handle` as key and `double` as value type
 * @tparam GeomTraits a model of SegmentationGeomTraits
 *
 * @param polyhedron surface mesh on which SDF values are computed
 * @param[out] sdf_values the SDF value of each facet
 * @param cone_angle opening angle in radians for the cone of each facet
 * @param number_of_rays number of rays picked in the cone of each facet. In our experiments, we observe that increasing the number of rays beyond the default has little effect on the quality of the segmentation result
 * @param postprocess if `true`, `CGAL::postprocess_sdf_values` is called on raw SDF value computed.
 * @param traits traits class
 *
 * @return minimum and maximum raw SDF values if @a postprocess is `true`, otherwise minimum and maximum SDF values (before linear normalization)
 */
template <class Polyhedron, class SDFPropertyMap, class GeomTraits
#ifndef BOOST_NO_FUNCTION_TEMPLATE_DEFAULT_ARGS
= typename Polyhedron::Traits
#endif
>
std::pair<double, double>
compute_sdf_values( const Polyhedron& polyhedron,
                    SDFPropertyMap sdf_values,
                    double cone_angle = 2.0 / 3.0 * CGAL_PI,
                    int number_of_rays = 25,
                    bool postprocess = true,
                    GeomTraits traits = GeomTraits())
{
  return compute_sdf_values<true, Polyhedron, SDFPropertyMap, GeomTraits>
         (polyhedron, sdf_values, cone_angle, number_of_rays, postprocess, traits);
}


/*!
 * \ingroup PkgSurfaceSegmentation
 * @brief Function post-processing raw SDF values computed per facet.
 *
 * Post-processing steps applied :
 *   - Facets with -1 SDF values are assigned the average SDF value of their edge-adjacent neighbors.
 *     If there is still a facet having -1 SDF value, the minimum valid SDF value assigned to it. Note that this step is not inherited from the paper.
 *     The main reason for not assigning 0 to facets with no SDF values (i.e. -1) is that it can obstruct log-normalization process which takes place at the beginning of `CGAL::segment_from_sdf_values`.
 *   - SDF values are smoothed with bilateral filtering.
 *   - SDF values are linearly normalized between [0,1].
 *
 * See the section \ref Surface_mesh_segmentationPostprocessing for more details.
 *
 * @pre @a polyhedron.is_pure_triangle()
 * @pre Raw values should be greater or equal to 0. -1 indicates when no value could be computed
 *
 * @tparam Polyhedron a %CGAL polyhedron
 * @tparam SDFPropertyMap  a `ReadWritePropertyMap` with `Polyhedron::Facet_const_handle` as key and `double` as value type
 *
 * @param polyhedron surface mesh on which SDF values are computed
 * @param[in, out] sdf_values the SDF value of each facet
 *
 * @return minimum and maximum SDF values before linear normalization
 */
template<class Polyhedron, class SDFPropertyMap>
std::pair<double, double>
postprocess_sdf_values(const Polyhedron& polyhedron, SDFPropertyMap sdf_values)
{
  CGAL_precondition(polyhedron.is_pure_triangle());
  return internal::Postprocess_sdf_values<Polyhedron>().postprocess(polyhedron,
         sdf_values);
}


/*!
 * \ingroup PkgSurfaceSegmentation
 * @brief Function computing the segmentation of a surface mesh given an SDF value per facet.
 *
 * This function fills a property map which associates a segment-id (in [0, number of segments -1])
 * or a cluster-id (in [0, `number_of_clusters` -1]) to each facet.
 * A segment is a set of connected facets which are placed under the same cluster (see \cgalFigureRef{Cluster_vs_segment}).
 *
 * \note Log-normalization is applied on `sdf_values` before segmentation.
 *       As described in the original paper \cgalCite{shapira2008consistent},
 *       this normalization is done to preserve thin parts of the mesh
 *       by increasing the distance between smaller SDF values and reducing
 *       it between larger ones.
 * \note There is no direct relation between the parameter `number_of_clusters`
 * and the final number of segments after segmentation. However, setting a large number of clusters will result in a detailed segmentation of the mesh with a large number of segments.
 *
 * @pre @a polyhedron.is_pure_triangle()
 * @pre @a number_of_clusters > 0
 *
 * @tparam Polyhedron a %CGAL polyhedron
 * @tparam SDFPropertyMap  a `ReadablePropertyMap` with `Polyhedron::Facet_const_handle` as key and `double` as value type
 * @tparam SegmentPropertyMap a `ReadWritePropertyMap` with `Polyhedron::Facet_const_handle` as key and `int` as value type
 * @tparam GeomTraits a model of SegmentationGeomTraits
 *
 * @param polyhedron surface mesh corresponding to the SDF values
 * @param sdf_values the SDF value of each facet between [0-1]
 * @param[out] segment_ids the segment or cluster id of each facet
 * @param number_of_clusters number of clusters for the soft clustering
 * @param smoothing_lambda factor which indicates the importance of the surface features for the energy minimization. It is recommended to choose a value in the interval [0,1]. See the section \ref Surface_mesh_segmentationGraphCut for more details.
 * @param output_cluster_ids if `false` fill `segment_ids` with segment-ids, and with cluster-ids otherwise (see \cgalFigureRef{Cluster_vs_segment})
 * @param traits traits class
 *
 * @return number of segments if `output_cluster_ids` is set to `false` and `number_of_clusters` otherwise
 */
template <class Polyhedron, class SDFPropertyMap, class SegmentPropertyMap,
         class GeomTraits
#ifndef BOOST_NO_FUNCTION_TEMPLATE_DEFAULT_ARGS
         = typename Polyhedron::Traits
#endif
         >
int
segment_from_sdf_values( const Polyhedron& polyhedron,
                         SDFPropertyMap sdf_values,
                         SegmentPropertyMap segment_ids,
                         int number_of_clusters = 5,
                         double smoothing_lambda = 0.26,
                         bool output_cluster_ids = false,
                         GeomTraits traits = GeomTraits())
{
  internal::Surface_mesh_segmentation<Polyhedron, GeomTraits> algorithm(
    polyhedron, traits);
  return algorithm.partition(number_of_clusters, smoothing_lambda, sdf_values,
                             segment_ids, !output_cluster_ids);
}

///\cond SKIP_IN_MANUAL
template < bool Fast_sdf_calculation_mode, class Polyhedron,
         class SegmentPropertyMap, class GeomTraits
#ifndef BOOST_NO_FUNCTION_TEMPLATE_DEFAULT_ARGS
         = typename Polyhedron::Traits
#endif
         >
int
compute_sdf_values_and_segment(const Polyhedron& polyhedron,
                               SegmentPropertyMap segment_ids,
                               double cone_angle = 2.0 / 3.0 * CGAL_PI,
                               int number_of_rays = 25,
                               int number_of_clusters = 5,
                               double smoothing_lambda = 0.26,
                               bool output_cluster_ids = false,
                               GeomTraits traits = GeomTraits())
{
  typedef std::map< typename Polyhedron::Facet_const_handle, double>
  Facet_double_map;
  Facet_double_map internal_sdf_map;
  boost::associative_property_map<Facet_double_map> sdf_property_map(
    internal_sdf_map);

  compute_sdf_values<Fast_sdf_calculation_mode, Polyhedron, boost::associative_property_map<Facet_double_map>, GeomTraits>
  (polyhedron, sdf_property_map, cone_angle, number_of_rays, true, traits);
  return segment_from_sdf_values<Polyhedron, boost::associative_property_map<Facet_double_map>, SegmentPropertyMap, GeomTraits>
         (polyhedron, sdf_property_map, segment_ids, number_of_clusters,
          smoothing_lambda, output_cluster_ids, traits);
}
/// \endcond


/*!
 * \ingroup PkgSurfaceSegmentation
 * @brief Function computing the segmentation of a surface mesh.
 *
 * This function is equivalent to calling the functions `CGAL::compute_sdf_values()` and
 * `CGAL::segment_from_sdf_values()` with the same parameters.
 *
 * \note There is no direct relation between the parameter `number_of_clusters`
 * and the final number of segments after segmentation. However, setting a large number of clusters will result in a detailed segmentation of the mesh with a large number of segments.
 * \note For computing segmentations of the mesh with different parameters (i.e. number of levels, and smoothing lambda),
 * it is more efficient to first compute the SDF values using `CGAL::compute_sdf_values()` and use them in different calls to
 * `CGAL::segment_from_sdf_values()`.
 *
 * @pre @a polyhedron.is_pure_triangle()
 * @pre @a number_of_clusters > 0
 *
 * @tparam Polyhedron a %CGAL polyhedron
 * @tparam SegmentPropertyMap a `ReadWritePropertyMap` with `Polyhedron::Facet_const_handle` as key and `int` as value type
 * @tparam GeomTraits a model of SegmentationGeomTraits
 *
 * @param polyhedron surface mesh on which SDF values are computed
 * @param[out] segment_ids the segment or cluster id of each facet
 * @param cone_angle opening angle in radians for the cone of each facet
 * @param number_of_rays number of rays picked in the cone of each facet. In our experiments, we observe that increasing the number of rays beyond the default has a little effect on the quality of the segmentation result
 * @param number_of_clusters number of clusters for the soft clustering
 * @param smoothing_lambda factor which indicates the importance of the surface features for the energy minimization. It is recommended to choose a value in the interval [0,1]. See the section \ref Surface_mesh_segmentationGraphCut for more details.
 * @param output_cluster_ids if `false` fill `segment_ids` with segment-ids, and with cluster-ids otherwise (see \cgalFigureRef{Cluster_vs_segment})
 * @param traits traits class
 *
 * @return number of segments if `output_cluster_ids` is set to `false` and `number_of_clusters` otherwise
 */
template < class Polyhedron, class SegmentPropertyMap, class GeomTraits
#ifndef BOOST_NO_FUNCTION_TEMPLATE_DEFAULT_ARGS
= typename Polyhedron::Traits
#endif
>
int
compute_sdf_values_and_segment(const Polyhedron& polyhedron,
                               SegmentPropertyMap segment_ids,
                               double cone_angle = 2.0 / 3.0 * CGAL_PI,
                               int number_of_rays = 25,
                               int number_of_clusters = 5,
                               double smoothing_lambda = 0.26,
                               bool output_cluster_ids = false,
                               GeomTraits traits = GeomTraits())
{
  return compute_sdf_values_and_segment<true, Polyhedron, SegmentPropertyMap, GeomTraits>
         (polyhedron, segment_ids, cone_angle, number_of_rays, number_of_clusters,
          smoothing_lambda, output_cluster_ids, traits);
}


#ifdef BOOST_NO_FUNCTION_TEMPLATE_DEFAULT_ARGS
template <bool Fast_sdf_calculation_mode, class Polyhedron, class SDFPropertyMap>
std::pair<double, double>
compute_sdf_values(const Polyhedron& polyhedron,
                   SDFPropertyMap sdf_values,
                   double cone_angle = 2.0 / 3.0 * CGAL_PI,
                   int number_of_rays = 25,
                   bool postprocess = true,
                   typename Polyhedron::Traits traits = typename Polyhedron::Traits())
{
  return compute_sdf_values<Fast_sdf_calculation_mode, Polyhedron, SDFPropertyMap, typename Polyhedron::Traits>
         (polyhedron, sdf_values, cone_angle, number_of_rays, postprocess, traits);
}

template < class Polyhedron, class SDFPropertyMap>
std::pair<double, double>
compute_sdf_values(const Polyhedron& polyhedron,
                   SDFPropertyMap sdf_values,
                   double cone_angle = 2.0 / 3.0 * CGAL_PI,
                   int number_of_rays = 25,
                   bool postprocess = true,
                   typename Polyhedron::Traits traits = typename Polyhedron::Traits())
{
  return compute_sdf_values<true, Polyhedron, SDFPropertyMap, typename Polyhedron::Traits>
         (polyhedron, sdf_values, cone_angle, number_of_rays, postprocess, traits);
}

template <class Polyhedron, class SDFPropertyMap, class SegmentPropertyMap>
int
segment_from_sdf_values(const Polyhedron& polyhedron,
                        SDFPropertyMap sdf_values,
                        SegmentPropertyMap segment_ids,
                        int number_of_clusters = 5,
                        double smoothing_lambda = 0.26,
                        bool output_cluster_ids = false,
                        typename Polyhedron::Traits traits = typename Polyhedron::Traits())
{
  return segment_from_sdf_values<Polyhedron, SDFPropertyMap, SegmentPropertyMap, typename Polyhedron::Traits>
         (polyhedron, sdf_values, segment_ids, number_of_clusters, smoothing_lambda,
          output_cluster_ids, traits);
}

template <bool Fast_sdf_calculation_mode, class Polyhedron, class SegmentPropertyMap>
int
compute_sdf_values_and_segment(const Polyhedron& polyhedron,
                               SegmentPropertyMap segment_ids,
                               double cone_angle = 2.0 / 3.0 * CGAL_PI,
                               int number_of_rays = 25,
                               int number_of_clusters = 5,
                               double smoothing_lambda = 0.26,
                               bool output_cluster_ids = false,
                               typename Polyhedron::Traits traits = typename Polyhedron::Traits())
{
  return compute_sdf_values_and_segment< Fast_sdf_calculation_mode, Polyhedron, SegmentPropertyMap, typename Polyhedron::Traits>
         (polyhedron, segment_ids, cone_angle, number_of_rays, number_of_clusters,
          smoothing_lambda, output_cluster_ids, traits);
}

template <class Polyhedron, class SegmentPropertyMap>
int
compute_sdf_values_and_segment(const Polyhedron& polyhedron,
                               SegmentPropertyMap segment_ids,
                               double cone_angle = 2.0 / 3.0 * CGAL_PI,
                               int number_of_rays = 25,
                               int number_of_clusters = 5,
                               double smoothing_lambda = 0.26,
                               bool output_cluster_ids = false,
                               typename Polyhedron::Traits traits = typename Polyhedron::Traits())
{
  return compute_sdf_values_and_segment<true, Polyhedron, SegmentPropertyMap, typename Polyhedron::Traits>
         (polyhedron, segment_ids, cone_angle, number_of_rays, number_of_clusters,
          smoothing_lambda, output_cluster_ids, traits);
}


#endif

}//namespace CGAL

#endif // CGAL_SURFACE_MESH_SEGMENTATION_MESH_SEGMENTATION_H //