#ifndef IGL_QSLIM_OPTIMAL_COLLAPSE_EDGE_CALLBACKS_H
#define IGL_QSLIM_OPTIMAL_COLLAPSE_EDGE_CALLBACKS_H
#include "igl_inline.h"
#include <Eigen/Core>
#include <functional>
#include <vector>
#include <tuple>
namespace igl
{

  // Prepare callbacks for decimating edges using the qslim optimal placement
  // metric.
  //
  // Inputs:
  //   E  #E by 2 list of working edges
  //   quadrics  reference to list of working per vertex quadrics 
  //   v1  working variable to maintain end point of collapsed edge
  //   v2  working variable to maintain end point of collapsed edge
  // Outputs
  //   cost_and_placement  callback for evaluating cost of edge collapse and
  //     determining placement of vertex (see collapse_edge)
  //   pre_collapse  callback before edge collapse (see collapse_edge)
  //   post_collapse  callback after edge collapse (see collapse_edge)
  IGL_INLINE void qslim_optimal_collapse_edge_callbacks(
    Eigen::MatrixXi & E,
    std::vector<std::tuple<Eigen::MatrixXd,Eigen::RowVectorXd,double> > & 
      quadrics,
    int & v1,
    int & v2,
    std::function<void(
      const int e,
      const Eigen::MatrixXd &,
      const Eigen::MatrixXi &,
      const Eigen::MatrixXi &,
      const Eigen::VectorXi &,
      const Eigen::MatrixXi &,
      const Eigen::MatrixXi &,
      double &,
      Eigen::RowVectorXd &)> & cost_and_placement,
    std::function<bool(const int)> & pre_collapse,
    std::function<void(const int,const bool)> & post_collapse);
}
#ifndef IGL_STATIC_LIBRARY
#  include "qslim_optimal_collapse_edge_callbacks.cpp"
#endif
#endif