/*
 * Software License Agreement (BSD License)
 *
 *  Copyright (c) 2008-2014, Willow Garage, Inc.
 *  Copyright (c) 2014-2015, Open Source Robotics Foundation
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of Open Source Robotics Foundation nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 */

/* Author: Ioan Sucan */

#ifndef FCL_KNN_NEAREST_NEIGHBORS_H
#define FCL_KNN_NEAREST_NEIGHBORS_H

#include <vector>
#include <boost/bind.hpp>
#include <boost/function.hpp>

namespace fcl
{
/// @brief Abstract representation of a container that can perform nearest neighbors queries
template<typename _T>
class NearestNeighbors
{
public:

  /// @brief The definition of a distance function
  typedef boost::function<double(const _T&, const _T&)> DistanceFunction;

  NearestNeighbors(void)
  {
  }

  virtual ~NearestNeighbors(void)
  {
  }

  /// @brief Set the distance function to use
  virtual void setDistanceFunction(const DistanceFunction &distFun)
  {
    distFun_ = distFun;
  }

  /// @brief Get the distance function used
  const DistanceFunction& getDistanceFunction(void) const
  {
    return distFun_;
  }

  /// @brief Clear the datastructure
  virtual void clear(void) = 0;

  /// @brief Add an element to the datastructure
  virtual void add(const _T &data) = 0;

  /// @brief Add a vector of points
  virtual void add(const std::vector<_T> &data)
  {
    for (typename std::vector<_T>::const_iterator elt = data.begin() ; elt != data.end() ; ++elt)
      add(*elt);
  }

  /// @brief Remove an element from the datastructure
  virtual bool remove(const _T &data) = 0;

  /// @brief Get the nearest neighbor of a point
  virtual _T nearest(const _T &data) const = 0;

  /// @brief Get the k-nearest neighbors of a point
  virtual void nearestK(const _T &data, std::size_t k, std::vector<_T> &nbh) const = 0;

  /// @brief Get the nearest neighbors of a point, within a specified radius
  virtual void nearestR(const _T &data, double radius, std::vector<_T> &nbh) const = 0;

  /// @brief Get the number of elements in the datastructure
  virtual std::size_t size(void) const = 0;

  /// @brief Get all the elements in the datastructure
  virtual void list(std::vector<_T> &data) const = 0;

protected:

  /// @brief The used distance function
  DistanceFunction distFun_;

};
}


#endif
