// Copyright (c) 2005  Stanford University (USA).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; version 2.1 of the License.
// See the file LICENSE.LGPL distributed with CGAL.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL: svn+ssh://scm.gforge.inria.fr/svn/cgal/trunk/Kinetic_data_structures/include/CGAL/Kinetic/Delaunay_triangulation_2.h $
// $Id: Delaunay_triangulation_2.h 34827 2006-10-18 00:39:13Z drussel $
// 
//
// Author(s)     : Daniel Russel <drussel@alumni.princeton.edu>

#ifndef CGAL_KINETIC_KINETIC_TRIANGULATION_2_H
#define CGAL_KINETIC_KINETIC_TRIANGULATION_2_H
#include <CGAL/Kinetic/basic.h>

#include <CGAL/Kinetic/Triangulation_face_base_2.h>
#include <CGAL/Kinetic/Triangulation_vertex_base_2.h>
#include <CGAL/Kinetic/Triangulation_visitor_base_2.h>
#include <CGAL/Kinetic/Active_objects_batch_listener_helper.h>
#include <CGAL/Kinetic/Simulator_kds_listener.h>
#include <CGAL/Kinetic/internal/tds_2_helpers.h>
#include <CGAL/Triangulation_2.h>
#include <CGAL/Kinetic/Ref_counted.h>
#include <iterator>
#include <CGAL/Kinetic/Event_base.h>
#include <CGAL/Kinetic/Triangulation_default_traits_2.h>

CGAL_KINETIC_BEGIN_NAMESPACE
#ifdef NDEBUG
#define CGAL_TRIANGULATION_2_DEBUG(x)
#else
#define CGAL_TRIANGULATION_2_DEBUG(x) x
#endif

template <class KDel>
struct Triangulation_event: public Event_base<KDel*> {
  typedef Event_base<KDel*>  P;
  Triangulation_event(const typename KDel::Certificate_data &c,
				   const typename KDel::Face_handle &e,
				   KDel *kdel): P(kdel), c_(c), e_(e) {}
  typename KDel::Certificate_data &certificate() const {
    return c_;
  }
  const typename KDel::Face_handle face() const {
    return e_;
  }
  KDel* kdel() {
    return P::kds();
  }

  KDel* kdel() const {
    return P::kds();
  }
  void process() {
    kdel()->flip(e_, c_);
  }

  void audit(typename KDel::Event_key k) const {
    kdel()->audit_event(k, e_);
  }

  CGAL::Comparison_result compare_concurrent(typename KDel::Event_key a,
					     typename KDel::Event_key b) const {
    return kdel()->compare_concurrent(a, b);
  }	

  std::ostream& write(std::ostream &out) const
  {
    out << "Face " << e_->vertex(0)->point() << ", "
	<< e_->vertex(1)->point() 
	<< ", " << e_->vertex(2)->point() ;
    return out;
  }

  typename KDel::Certificate_data c_;
  const typename KDel::Face_handle e_;
};





//! A 2D kinetic triangulation.
/*!  There is one certificate for each face. For the internal faces
  (inside the convex hull), that certificate is for the face
  collapsing at which point we need to figure out which edge to flip.

  For the faces outside the convex hull, the certificate is for the
  edge that is CCW from the infinite vertex and for whether the other
  vertex on the edge leaves the convex hull.

  The annoying part is how to figure out which edge to flip when an
  internal face collapses.  As far as I can tell this requires
  evaluating which point is in the segment defined by which other two,
  so four 1D orientation predicates.
*/
template <class Simulation_traits_t, 
	  class Visitor= Triangulation_visitor_base_2,
	  class Triangulation
	  = CGAL::Triangulation_2<typename Simulation_traits_t::Instantaneous_kernel,
				  CGAL::Triangulation_data_structure_2<
	    Triangulation_vertex_base_2<typename Simulation_traits_t::Instantaneous_kernel>,
  CGAL::Kinetic::Triangulation_face_base_2<Simulation_traits_t > > >,
	  class Triangulation_traits_t= Triangulation_default_traits_2<Simulation_traits_t, Delaunay> >
class Triangulation_2:
  public Ref_counted<Triangulation_2<Simulation_traits_t, Visitor, Delaunay, Delaunay_traits_t> >
{

  typedef CGAL::Triangulation_2<typename Simulation_traits_t::Instantaneous_kernel,
				CGAL::Triangulation_data_structure_2<
    Ttriangulation_vertex_base_2<typename Simulation_traits_t::Instantaneous_kernel>,
    CGAL::Kinetic::Triangulation_face_base_2<Simulation_traits_t > > > Basic_Delaunay;

public:
  typedef Triangulation_traits_t Traits;
  typedef Simulation_traits_t Simulation_traits;
  typedef Triangulation_2<Simulation_traits, Visitor, Delaunay, Traits> This;

  typedef typename Simulation_traits::Kinetic_kernel Kinetic_kernel;
  typedef typename Simulation_traits::Simulator Simulator;
  typedef typename Simulation_traits::Active_points_2_table Moving_point_table;

  typedef typename Moving_point_table::Key Point_key;
  typedef typename Simulator::Event_key Event_key;
  //typedef typename Simulator::Root_stack Root_stack;

  typedef typename Traits::Triangulation Triangulation;

  typedef typename Triangulation::Edge_circulator Edge_circulator;
  typedef typename Triangulation::Face_circulator Face_circulator;
  typedef typename Triangulation::Finite_edges_iterator Finite_edges_iterator;
  //typedef typename Triangulation::Edge_iterator Edge_iterator;

  typedef typename Triangulation::Geom_traits::Point_2 Del_point;

  typedef typename Triangulation::Vertex_handle Vertex_handle;
  typedef typename Triangulation::Face_handle Face_handle;
  typedef typename Triangulation::Edge Edge;
  typedef typename Triangulation::All_faces_iterator Face_iterator;
  typedef typename Triangulation::All_edges_iterator Edge_iterator;
  typedef typename Traits::Certificate_data Certificate_data;
  typedef typename Traits::Time Time;
  typedef internal::Triangulation_data_structure_helper_2<typename Triangulation::Triangulation_data_structure> TDS_helper;

  typedef Triangulation_event<This> Event;
  
  //friend class Delaunay_edge_failure_event<This>;
  //friend class Delaunay_hull_edge_failure_event<This>;

  typedef typename CGAL::Kinetic::Simulator_kds_listener<typename Simulator::Listener, This> Simulator_listener;
  friend  class CGAL::Kinetic::Simulator_kds_listener<typename Simulator::Listener, This>;
  typedef typename CGAL::Kinetic::Active_objects_batch_listener_helper<typename Moving_point_table::Listener, This> Moving_point_table_listener;
  friend class CGAL::Kinetic::Active_objects_batch_listener_helper<typename Moving_point_table::Listener, This>;

  /*struct Compare_edges{
    bool operator()(const Edge &a, const Edge &b) const {
      Point_key a0, a1, b0, b1;
      a0= a.first->vertex((a.second+1)%3)->point();
      a1= a.first->vertex((a.second+2)%3)->point();
      b0= b.first->vertex((b.second+1)%3)->point();
      b1= b.first->vertex((b.second+2)%3)->point();
      if (a0 > a1) std::swap(a0, a1);
      if (b0 > b1) std::swap(b0, b1);
      if (a0 < b0) return true;
      else if (a0 > b0) return false;
      else return a1 < b1;
    }
    };*/

  void init_data(bool insert) {
    siml_ = Simulator_listener(traits_.simulator_handle(), this);
    motl_= Moving_point_table_listener(traits_.active_points_2_table_handle(), this, insert);
    has_certificates_=false; 
    clear_stats();
   
    batching_=false;
  }

public:

  Triangulation_2(Traits st,
		  Triangulation del,
		  Visitor w= Visitor()): 
    traits_(st),
    watcher_(w),
    del_(del) {
    vhs_.resize(del_.number_of_vertices());
    for (typename Triangulation::Vertex_iterator vit = del_.vertices_begin(); vit != del_.vertices_end(); ++vit) {
      CGAL_assertion(vit->point().to_index() < del_.number_of_vertices());
      vhs_[vit->point().to_index()]=vit;
    }
    init_data(false);
  
    set_has_certificates(true);
  }

  Delaunay_triangulation_2(Simulation_traits st,
			   Visitor w= Visitor()): 
    traits_(st),
    watcher_(w),
    del_(traits_.instantaneous_kernel_object()) {
    init_data(true);
    set_has_certificates(true);
  }



  //! Just write the objects in order;
  void write(std::ostream &out) const
  {
    out << del_;
  }

  void clear_stats() {
    num_events_=0;
    // num_single_certificates_=0;
  }

  void write_stats(std::ostream &out) const {
    out << "Num events is " << num_events_ << std::endl;
  }

  const Triangulation &triangulation(const typename Simulator::NT &t) const
  {
    //update_instantaneous_kernel_time();
    del_.geom_traits().set_time(t);
    return del_;
  }

  const Triangulation &triangulation() const
  {
    return del_;
  }


  // for Qt_triangulation
  /*Event_key null_event() const {
    return traits_.simulator_handle()->null_event();
    }*/

  /*const Simulation_traits& simulation_traits_object() const {
    return traits_;
    }*/

  typedef typename Triangulation::Triangulation_data_structure Triangulation_data_structure;
  const Triangulation_data_structure &triangulation_data_structure() const
  {
    return del_.tds();
  }

  bool is_batch_editing() const {
    return batching_;
  }

  void set_is_batch_editing(bool tf) {
    if (tf) {
      batching_=true;
    } else if (batching_) {

      //unsigned int num_certs= num_certificates_;
      // this is important that it be before update
      batching_=false;

      //std::sort(batched_certs_.begin(), batched_certs_.end(), Compare_edges());
     
      /*batched_certs_.erase(std::unique(batched_certs_.begin(), 
				       batched_certs_.end()), 
				       batched_certs_.end());*/
     
      
      for (unsigned int i=0; i< batched_certs_.size(); ++i){
	//Point_key s=TDS_helper::origin(batched_certs_[i])->point();
	//Point_key t=TDS_helper::destination(batched_certs_[i])->point();
	
	//std::cout << std::min(s,t) << "--" << std::max(s,t) << std::endl;
	update_face(batched_certs_[i]);
      }
      
      batched_certs_.clear();
      /*CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, 
       *traits_.simulator_handle() << std::endl;);*/
      //int dnum= num_certificates_-num_certs;
      //std::cout << "Edit had " << dnum << " certificate computations" << std::endl;

      //audit();
    }
  }
  
  /*const std::set<Edge>& recent_edges() const {
    return new_edges_;
    }*/

  //! Verify that the current state of the
  void audit()const;

  void audit_event(Event_key k, Face_handle e) const {
    if (e->event() !=k) {
      std::cerr << "AUDIT FAILURE orphan event " << k << std::endl;
    }
    CGAL_assertion(e->event() ==k);
  }

  void set_has_certificates(bool tf, bool no_failures=false) {
    if (tf == has_certificates_){

    } else {
      if (tf==true && del_.dimension()==2) {
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "DELAUNAY2: Creating certificates."<< std::endl);
	if (no_failures) {
	  for (Face_iterator f = del_.all_faces_begin(); f != del_.all_faces_end(); ++f) {
	    f->set_event(traits_.simulator_handle()->null_event());
	  }
	}  
	/*for (typename Triangulation::All_vertices_iterator vit = del_.all_vertices_begin(); 
	     vit != del_.all_vertices_end(); ++vit) {
	  int deg=TDS_helper::low_degree(vit, del_.tds());
	  CGAL_assertion(deg >=3);
	  Vertex_handle vh= vit;
	  vh->set_neighbors(deg);
	  CGAL_DELAUNAY_2_DEBUG(std::cout << "Set degree of " << vit->point() << " to " << deg << std::endl);
	  //vit->set_neighbors_is_changed(false);
	  }*/
	if (!no_failures) {
	  for (Face_iterator eit = del_.all_faces_begin(); eit != del_.all_faces_end(); ++eit) {
	    eit->set_event(Event_key());
	    update_face(*eit);
	  }
	}

	watcher_.create_faces(del_.all_faces_begin(), del_.all_faces_end());
      } else if (tf==false) { 
	for (Face_iterator f = del_.all_faces_begin(); f != del_.all_faces_end(); ++f) {
	  delete_certificate(f);
	}
      } 
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, 
		       *traits_.simulator_handle() << std::endl;);
      has_certificates_=tf;
    }
  }
  bool has_certificates() {
    return has_certificates_;
  }

  void erase(Point_key k) {
    // erase all incident certificates
    Vertex_handle vh= vertex_handle(k);
    if (vh == Vertex_handle()) {
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "Point " << k << " is not in triangulation on removal."<< std::endl);
      return;
    }
    watcher_.remove_vertex(vh);
    if (has_certificates_) {
      Face_circulator fc= vh->incident_faces(), fe=fc;
      if (fc != NULL) {
	do {
	  for (unsigned int j=0; j<3; ++j) {
	    Edge e(fc, j);
	    Event_key k= TDS_helper::get_undirected_edge_label(e);
	    delete_certificate(e);
	  }
	  ++fc;
	} while (fc != fe);
      }
    }
    // remove from triangulation
    del_.geom_traits().set_time(traits_.rational_current_time());
    del_.remove(vh);
    //new_edges_.clear();
    if (del_.dimension()==2 && has_certificates_) {
      std::vector<Face_handle> faces;

      del_.get_conflicts(k,std::back_inserter(faces));
      for (unsigned int i=0; i< faces.size(); ++i) {
	for (unsigned int j=0; j<3; ++j) {
	  update_neighbors(faces[i]->vertex(j));
	}
      }
      for (unsigned int i=0; i< faces.size(); ++i) {
	for (unsigned int j=0; j<3; ++j) {
	  update_vertex(faces[i]->vertex(j));
	}
      }
      for (unsigned int i=0; i< faces.size(); ++i) {
	for (unsigned int j=0; j<3; ++j) {
	  Edge e(faces[i],j);
	  //Event_key k= TDS_helper::get_undirected_edge_label(e);
	  // a bit redundant for certificates which don't fail
	  update_edge(e);
	  //new_edges_.insert(e);
	}
      }
      watcher_.create_faces(faces.begin(), faces.end());
    }

  }

  //! The assertion will catch that the object is in the same sorted order
  void set(Point_key k) {
    //std::cout << "Object changed " << k << std::endl;

    //new_edges_.clear();
    traits_.point_changed(k);
    if (del_.dimension() != 2) {
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME,"Triangulation is still 1D.\n");
      return;
    }

    Vertex_handle vh=vertex_handle(k);
    if (vh == Vertex_handle()) {
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "Point " << k << " is not in triangulation on set."<< std::endl);
      return;
    }

    if (has_certificates_) {
      Face_handle f= vh->face(), fe= vh->face();
      int i= f->index(vh);
      do {
	//int i= fc->index(vh);
	Edge e0(f, i);
	delete_certificate(e0);
	update_edge(e0);
	Edge e1=Edge(f, (i+1)%3);
	delete_certificate(e1);
	update_edge(e1);
	f= f->neighbor((i+1)%3);
	i= f->index(vh);
      } while (f != fe);
    }

   
    watcher_.modify_vertex(vh);

    /*if (has_certificates_) {
      Face_handle f= vh->face(), fe= vh->face();
      int i= f->index(vh);
      do {
	//int i= fc->index(vh);
	Edge e0(f, i);
	update_edge(e0);
	Edge e1=Edge(f, (i+1)%3);
	update_edge(e1);
	f= f->neighbor((i+1)%3);
	i= f->index(vh);
      } while (f != fe);
      }*/
    //write(std::cout);
  }


  void insert(Point_key k) {
    // evil hack
    CGAL_precondition(k.to_index() >= vhs_.size() || vertex_handle(k) == Vertex_handle());
    CGAL_DELAUNAY_2_DEBUG(std::cout << "Inserting " << k << std::endl);
    bool was_2d= (del_.dimension()==2);

    del_.geom_traits().set_time(traits_.rational_current_time());
    if (was_2d && has_certificates_) {
      //std::cout << "removing extra certificates.\n";
      std::vector<Face_handle> faces;
      del_.get_conflicts(k, std::back_inserter(faces));
      for (unsigned int i=0; i< faces.size(); ++i) {
	Face_handle f= faces[i];
	for (unsigned int j=0; j<3; ++j) {
	  Edge e(f, j);
	  Event_key k= TDS_helper::get_undirected_edge_label(e);
	  delete_certificate(e);
	}
      }
      watcher_.remove_faces(faces.begin(), faces.end());

      if (faces.empty()) {
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "DELAUNAY vertex not successfully inserted " << k << std::endl);
	return;
      }
    }
    Vertex_handle vh= del_.insert(k);
    set_vertex_handle(k, vh);
    
    CGAL_assertion(vertex_handle(k) != Vertex_handle());
    
    CGAL_DELAUNAY_2_DEBUG(std::cout << "Vertex " << vertex_handle(k)->point() 
			  << " has " << vertex_handle(k)->neighbors() << std::endl);
    watcher_.create_vertex(vertex_handle(k));

    // now have to update
    if (has_certificates_) {
   

      if (!was_2d && del_.dimension()==2) {
	vh->set_neighbors(vh->degree());
	has_certificates_=false;
	set_has_certificates(true); 
      } else if (del_.dimension() == 2) {
	update_neighbors(vh);
	update_vertex(vh);
	// update vertices
	{
	  Face_handle f= vh->face(), fe= vh->face();
	  int i= f->index(vh);
	  do {
	    update_neighbors(f->vertex((i+1)%3));
	    f= f->neighbor((i+1)%3);
	    i= f->index(vh);
	  } while (f != fe);
	} 

	{
	  Face_handle f= vh->face(), fe= vh->face();
	  int i= f->index(vh);
	  do {
	    update_vertex(f->vertex((i+1)%3));
	    f= f->neighbor((i+1)%3);
	    i= f->index(vh);
	  } while (f != fe);
	} 
	// update edges 
	{
	  Face_handle f= vh->face(), fe= vh->face();
	  int i= f->index(vh);
	  do {
	    //int i= fc->index(vh);
	    Edge e0(f, i);
	    update_edge(e0);
	    Edge e1=Edge(f, (i+1)%3);
	    update_edge(e1);
	    f= f->neighbor((i+1)%3);
	    i= f->index(vh);
	  } while (f != fe);
	}
      }
    } else {
      vertex_handle(k)->set_neighbors(vh->degree());
    }
    //write(std::cout);
    //if (del_.dimension()==2) audit();
  }



  Comparison_result compare_concurrent(Event_key a, Event_key b) const {
    Edge ea= traits_.simulator_handle()->template event<Event>(a).edge();
    Edge eb= traits_.simulator_handle()->template event<Event>(b).edge();
    return traits_.compare_concurrent(a, ea, b, eb);
  }




  Edge flip(const Edge &e, Certificate_data cert) {
    ++num_events_;
    CGAL_precondition(!batching_);
    CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "\n\n\n\n\n\nDELAUNAY Flipping edge "
		     << TDS_helper::origin(e)->point()
		     << TDS_helper::destination(e)->point() 
		     << " to get " << TDS_helper::third_vertex(e)->point()
		     << ", " << TDS_helper::mirror_vertex(e)->point()<< std::endl);
    //CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, TDS_helper::destination(e)->point() << std::endl);
    //CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, " at "  << traits_.simulator()->current_time() << std::endl);

    

    Face_handle face= e.first;
    int index= e.second;
    Face_handle mirror_face = face->neighbor(index);
    int mirror_index =face->mirror_index(index);
    Edge em(mirror_face,mirror_index);
    CGAL_precondition(mirror_face->neighbor(mirror_index) == face);

    Face_handle bef;
    int bei;

    if (!traits_.is_exact()
	&& del_.is_edge(TDS_helper::third_vertex(e), TDS_helper::mirror_vertex(e),
			bef, bei)) {
      // we have a numeric error, lets try to rebuild the neighboring certificates
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME,
		       "DELAUNAY ERROR not flipping unflippable edge" << std::endl);
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, 
		       *traits_.simulator_handle() << std::endl;);
      //make this better
      //double ub=to_interval(traits_.simulator_handle()->next_event_time()).second;
      Edge bad_edge(bef, bei);
      Event_key bek= TDS_helper::get_undirected_edge_label(bad_edge);
      
      if (bek == traits_.simulator_handle()->null_event()) {
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME,
			 "Dropping the event." << std::endl);
	TDS_helper::set_undirected_edge_label(e, Event_key());
	return e;
      } else {

	double ub = CGAL::to_interval(traits_.simulator_handle()->event_time(bek)).second;
	
	ub= (std::max)(ub+.0000001, 
		       nextafter(ub, (std::numeric_limits<double>::max)()));
	Time t(ub);
	CGAL_precondition(CGAL::compare(t, traits_.simulator_handle()->next_event_time()) == CGAL::LARGER);
	Event_key k =traits_.simulator_handle()->new_event(t, Event(cert, e, this));
	TDS_helper::set_undirected_edge_label(e, k);
	return e;
      }
    }
    CGAL_precondition(!del_.is_edge(TDS_helper::third_vertex(e), TDS_helper::mirror_vertex(e),
				    bef, bei));

    TDS_helper::set_directed_edge_label(e, Event_key());
    TDS_helper::set_directed_edge_label(em, Event_key());

    delete_certificate(Edge(face, (index+1)%3));
    delete_certificate(Edge(face, (index+2)%3));
    delete_certificate(Edge(mirror_face, (mirror_index+1)%3));
    delete_certificate(Edge(mirror_face, (mirror_index+2)%3));

   
    watcher_.before_flip(e);
    del_.tds().flip(face,index);
   
    // we also know that CGAL preserves the edge index of the flipped edge
    mirror_index = mirror_face->index(face);
    index= face->index(mirror_face);

    Edge flipped_edge(face,index);
    Edge mirror_flipped_edge(face->neighbor(index), mirror_index);
    CGAL_assertion(mirror_flipped_edge == TDS_helper::mirror_edge(flipped_edge));
    //CGAL_postcondition(del_.is_face(face));

    CGAL_assertion(mirror_index == face->mirror_index(index));
    CGAL_assertion(mirror_face == face->neighbor(index));

    watcher_.after_flip(flipped_edge);

    decrease_neighbors(flipped_edge.first->vertex(flipped_edge.second));
    increase_neighbors(flipped_edge.first->vertex((flipped_edge.second+1)%3));
    increase_neighbors(flipped_edge.first->vertex((flipped_edge.second+2)%3));
    decrease_neighbors(mirror_flipped_edge.first->vertex(mirror_flipped_edge.second));

    // make sure it is not created by a 3-4 transition
    TDS_helper::set_directed_edge_label(flipped_edge, traits_.simulator_handle()->null_event());
    TDS_helper::set_directed_edge_label(mirror_flipped_edge, traits_.simulator_handle()->null_event());

    update_decreased_vertex(flipped_edge.first->vertex(flipped_edge.second));
    update_increased_vertex(flipped_edge.first->vertex((flipped_edge.second+1)%3));
    update_increased_vertex(flipped_edge.first->vertex((flipped_edge.second+2)%3));
    update_decreased_vertex(mirror_flipped_edge.first->vertex(mirror_flipped_edge.second));

    update_edge(Edge(flipped_edge.first, (flipped_edge.second+1)%3));
    update_edge(Edge(flipped_edge.first, (flipped_edge.second+2)%3));
    update_edge(Edge(mirror_flipped_edge.first, (mirror_flipped_edge.second+1)%3));
    update_edge(Edge(mirror_flipped_edge.first, (mirror_flipped_edge.second+2)%3));

    {
     std::pair<Time, Certificate_data> sp= traits_.certificate_failure_time(flipped_edge,cert);
      Event_key k =traits_.simulator_handle()->new_event(sp.first,
							 Event(sp.second, flipped_edge, this));
      TDS_helper::set_directed_edge_label(flipped_edge, k);
      TDS_helper::set_directed_edge_label(mirror_flipped_edge, k);
    }
    //write(std::cout);
    //new_edges_.clear();
    //new_edges_.insert(flipped_edge);

    CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "Created " << TDS_helper::origin(flipped_edge)->point());
    CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, TDS_helper::destination(flipped_edge)->point() << std::endl);

    return flipped_edge;
  }

  Visitor &visitor() {
    return watcher_;
  }

  const Visitor &visitor() const
  {
    return watcher_;
  }

protected:
  Traits traits_;
  Visitor watcher_;
  Triangulation del_;


  Simulator_listener siml_;
  Moving_point_table_listener motl_; 
  std::vector<Vertex_handle> vhs_;

  bool has_certificates_;
  bool batching_;
  std::vector<Edge> batched_certs_;


  mutable unsigned int num_events_;
  //mutable unsigned int num_single_certificates_;

  const typename Traits::Point_2& point(Point_key k) const
  {
    return traits_.point(k);
  }


  Vertex_handle vertex_handle(Point_key k) const {
    //if (k.to_index() >= vhs_.size()) return Vertex_handle();
    CGAL_precondition(k.to_index() < vhs_.size());
    return vhs_[k.to_index()];
  }
  void set_vertex_handle(Point_key k, Vertex_handle vh) {
    vhs_.resize(std::max(k.to_index()+1, vhs_.size()));
    vhs_[k.to_index()]=vh;
  }

  void update_vertex_to_degree_3(Vertex_handle vh) {
    CGAL_DELAUNAY_2_DEBUG(std::cout << "Degree 3 for " 
			  << vh->point() << std::endl);
    typename Triangulation::Edge_circulator ec= del_.incident_edges(vh);
    do {
      delete_certificate(*ec);
      ++ec;
    } while (ec != del_.incident_edges(vh));
  }

  void update_vertex_to_not_degree_3(Vertex_handle vh) {
    CGAL_DELAUNAY_2_DEBUG(std::cout << "Degree 4 for " 
			      << vh->point() << std::endl);
    typename Triangulation::Edge_circulator ec= del_.incident_edges(vh);
    do {
      if (TDS_helper::get_undirected_edge_label(*ec) == Event_key()) {
	// check other vertex, it it is not changed and not 3, build
	Vertex_handle ov= ec->first->vertex((ec->second+1)%3);
	if (ov== vh) {
	  ov= ec->first->vertex((ec->second+2)%3);
	}
	
	if (ov->neighbors() != 3){
	  new_certificate(*ec);
	  CGAL_DELAUNAY_2_DEBUG(std::cout << "New cert for "
				<< TDS_helper::origin(*ec)->point() << " " 
				<< TDS_helper::destination(*ec)->point() 
				<< std::endl);
	} else {
	  CGAL_DELAUNAY_2_DEBUG(std::cout << "Not creating cert for "
				<< TDS_helper::origin(*ec)->point() << " " 
				<< TDS_helper::destination(*ec)->point() 
				<< std::endl);
	}
      }
      ++ec;
    } while (ec != del_.incident_edges(vh));
  }

  void update_neighbors(Vertex_handle vh) {
    unsigned int deg= vh->degree();
    if (deg == vh->neighbors()) return;
    if (deg ==3) {
      vh->set_neighbors(3);
      //update_vertex_to_degree_3(vh);
    } else if (vh->neighbors()==3) {
      vh->set_neighbors(deg);
      //update_vertex_to_not_degree_3(vh);
    }  else {
      vh->set_neighbors(deg);
    }
  }
  
  void decrease_neighbors(Vertex_handle vh) {
    vh->set_neighbors(vh->neighbors()-1);
    CGAL_assertion(neighbors_ok(vh));
    //if (vh->neighbors() == 3) update_vertex_to_degree_3(vh);
  }

  void increase_neighbors(Vertex_handle vh) {
    vh->set_neighbors(vh->neighbors()+1);
    CGAL_assertion(neighbors_ok(vh));
    //if (vh->neighbors() == 4) update_vertex_to_not_degree_3(vh);
  }

  void update_vertex(Vertex_handle vh) {
    CGAL_precondition(neighbors_ok(vh));
    if (vh->neighbors() == 3) {
      update_vertex_to_degree_3(vh);
    } else if (vh->neighbors() == 4) {
      update_vertex_to_not_degree_3(vh);
    }
  }

  void update_decreased_vertex(Vertex_handle vh) {
    if (vh->neighbors() == 3) {
      update_vertex_to_degree_3(vh);
    } 
  }

 void update_increased_vertex(Vertex_handle vh) {
    if (vh->neighbors() == 4) {
      update_vertex_to_not_degree_3(vh);
    } 
  }

  bool neighbors_ok(Vertex_handle vh) const {
    return vh->degree() == vh->neighbors();
    //(vh->neighbors() == vh->degree() && vh->degree() <6 
    //|| vh->degree() >=5 && vh->neighbors() >=5);
  }

  void update_edge_no_batch(const Edge &e) {
    CGAL_DELAUNAY_2_DEBUG(std::cout << "Updating edge " 
			  << TDS_helper::origin(e)->point() << " " 
			  << TDS_helper::destination(e)->point() 
			  << std::endl);
    Vertex_handle ov=TDS_helper::origin(e);
    Vertex_handle dv=TDS_helper::destination(e);
    
    CGAL_precondition(neighbors_ok(ov));
    CGAL_precondition(neighbors_ok(dv));

    if (TDS_helper::get_undirected_edge_label(e) != Event_key()) {
      CGAL_DELAUNAY_2_DEBUG(std::cout << "Already has event " << std::endl);
      // can't do this since I create all edges around vertex of degree 4 at once
      // CGAL_assertion(0);
    } else if (ov->neighbors() ==3 
	       || dv->neighbors() ==3) {
      CGAL_DELAUNAY_2_DEBUG(std::cout << "One end has 3 " << std::endl);
    } else {
      //CGAL_DELAUNAY_2_DEBUG(std::cout << "New certificate" << std::endl);
      new_certificate(e);
    }
  }



  void update_edge(const Edge &e) {
    if (batching_) {
      //delete_certificate(e);
      batched_certs_.push_back(e);
    } else if (TDS_helper::get_undirected_edge_label(e) == Event_key()) {
      update_edge_no_batch(e);
    }
  }


  void new_certificate(Edge e) {
    CGAL_precondition(TDS_helper::get_undirected_edge_label(e) == Event_key());
    CGAL_DELAUNAY_2_DEBUG(std::cout << "\nMaking certificate for " << TDS_helper::origin(e)->point() << " " 
			  << TDS_helper::destination(e)->point() 
			  << " which would make " << TDS_helper::mirror_vertex(e)->point() << " " 
			  << TDS_helper::third_vertex(e)->point()
			  << std::endl);
    std::pair<Time, Certificate_data> sp= traits_.certificate_failure_time(e);
    Event_key k= traits_.simulator_handle()->new_event(sp.first, Event(sp.second, e, this));
    TDS_helper::set_undirected_edge_label(e, k);
  }

  void delete_certificate(Edge e) {
    CGAL_DELAUNAY_2_DEBUG(std::cout << "Cleaning edge " << TDS_helper::origin(e)->point() << " " << TDS_helper::destination(e)->point() << std::endl);
    Event_key k=  TDS_helper::get_undirected_edge_label(e);
    if (k != Event_key()) {
      traits_.simulator_handle()->delete_event(k);
      TDS_helper::set_undirected_edge_label(e, Event_key());
    }
  }


  Edge canonicalize(Edge e) const {
    if (e.first->neighbor(e.second) < e.first) {
      return TDS_helper::mirror_edge(e);
    } else {
      return e;
    }
  }
};

template <class Sim, class Del, class W, class T>
std::ostream &operator<<(std::ostream &out, const Delaunay_triangulation_2<Sim, Del, W, T> &kd)
{
  kd.write(out);
  return out;
}

template <class Sim, class Del, class W, class T>
void Delaunay_triangulation_2<Sim, Del, W, T>::audit() const
  {
    if (!has_certificates_) return;
    CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_SOME, "Auditing delaunay" << std::endl);
    
    if (del_.number_of_vertices() < 50) {
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_LOTS, *this);
    }
    if (del_.dimension() != 2) return;
    Basic_Delaunay sdel(traits_.instantaneous_kernel_object());
    sdel.geom_traits().set_time(traits_.rational_current_time());
    for (typename Triangulation::Finite_vertices_iterator cit= del_.finite_vertices_begin();
	 cit != del_.finite_vertices_end(); ++cit){
      sdel.insert(cit->point());
    }
    /*    sdel.insert(traits_.active_points_2_table_handle()->keys_begin(),
	  traits_.active_points_2_table_handle()->keys_end());*/

    //CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_LOTS, sdel << std::endl);

    if (del_.dimension() != sdel.dimension()) {
      CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE Dimensions don't match in audit" << std::endl);
      return;
    }
    CGAL_exactness_assertion(del_.dimension() == sdel.dimension());
   
   for (typename Triangulation::All_vertices_iterator vit = del_.all_vertices_begin();
	vit != del_.all_vertices_end(); ++vit) {
     if (vit->point() != Point_key()) {
       
       if (!neighbors_ok(vit)) {
	 CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE stored degree is " << vit->neighbors() 
			  << " and actual is " << vit->degree() << " for " << vit->point() << std::endl);
	 CGAL_exactness_assertion(neighbors_ok(vit));
       }
     }
   }
   for (typename Basic_Delaunay::All_vertices_iterator vit = sdel.all_vertices_begin();
	 vit != sdel.all_vertices_end(); ++vit) {
      bool found=false;
    
      //Object_key k= vit->point();
      for (typename Triangulation::All_vertices_iterator vit2= del_.all_vertices_begin();
	   vit2 != del_.all_vertices_end(); ++vit2) {
	//Object_key k2= vit2->point();
	if (vit->point() == vit2->point()) {
	  found=true;
	  //int d= vit->degree();
	  //int d2= vit2->degree();
	  if (vit->degree() != vit2->degree()) {
	    CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE Degrees don't match in: " 
			     << vit->point() << std::endl);
	  }
	  CGAL_exactness_assertion(vit->degree() == vit2->degree());


	}
      }
      if (!found) {
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE Matching vertex not found: " 
			 << vit->point() << std::endl);
      }
      CGAL_exactness_assertion(found);
     
    }

  

    typename Simulation_traits::Instantaneous_kernel ik= traits_.instantaneous_kernel_object();
    ik.set_time(traits_.rational_current_time());

    typename Simulation_traits::Instantaneous_kernel::Side_of_oriented_circle_2 ic2
      = ik.side_of_oriented_circle_2_object();
    for (typename Triangulation::Finite_edges_iterator fit = del_.finite_edges_begin(); 
	 fit != del_.finite_edges_end(); ++fit){
      Point_key k0= fit->first->vertex((fit->second+1)%3)->point();
      Point_key k2= fit->first->vertex((fit->second+2)%3)->point();
      Point_key k3= TDS_helper::mirror_vertex(*fit)->point();
      Point_key k1= TDS_helper::third_vertex(*fit)->point();
      if (k1== Point_key() || k3== Point_key()) continue;
      typename Triangulation::Geom_traits::Current_coordinates cc= del_.geom_traits().current_coordinates_object();
      typedef typename Triangulation::Geom_traits::Current_coordinates::result_type P2;
      P2 p0= cc(k0);
      P2 p1= cc(k1);
      P2 p2= cc(k2);
      P2 p3= cc(k3);
      if (ic2(k0, k1, k2, k3) != CGAL::ON_POSITIVE_SIDE) {
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE Failed certificate: " << k0 << " " << k1 << " " 
			 << k2 << " " << k3 << std::endl);
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE Points are: " << p0 << ": " << p1 << ": " << p2 
			 << ": " << p3 << std::endl);
      }
      CGAL_exactness_assertion(ic2(k0, k1, k2, k3) == CGAL::ON_POSITIVE_SIDE);
      
    }

    for (typename Triangulation::Edge_iterator fit = del_.edges_begin(); fit != del_.edges_end(); ++fit){
      if (TDS_helper::get_directed_edge_label(*fit) != 
	  TDS_helper::get_directed_edge_label(TDS_helper::mirror_edge(*fit))) {
	CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE mismatched labels on " 
			 << TDS_helper::origin(*fit)->point() << " " 
			 << TDS_helper::destination(*fit)->point() 
			 << " front has " << TDS_helper::get_directed_edge_label(*fit)
			 << " and back has " << TDS_helper::get_directed_edge_label(TDS_helper::mirror_edge(*fit))<< std::endl);
      }
      if (TDS_helper::origin(*fit)->degree()==3 || TDS_helper::destination(*fit)->degree()==3) {
	if (TDS_helper::get_undirected_edge_label(*fit) != Event_key()) {
	  CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE certificate on degree 3 edge: " 
			   << TDS_helper::origin(*fit)->point()
			   << " " <<  TDS_helper::destination(*fit)->point() 
			   << TDS_helper::origin(*fit)->degree() <<  " "
			   << TDS_helper::destination(*fit)->degree() << std::endl);
	} 
	CGAL_exactness_assertion(TDS_helper::get_undirected_edge_label(*fit) == Event_key());
      } else {
	if (TDS_helper::get_undirected_edge_label(*fit) == Event_key()) {
	  CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE no certificate on edge: " 
			   << TDS_helper::origin(*fit)->point()
			   << " " <<  TDS_helper::destination(*fit)->point() << std::endl);
	  CGAL_KINETIC_LOG(CGAL::Kinetic::LOG_NONE, "AUDIT FAILURE degrees are: " 
			   << TDS_helper::origin(*fit)->degree()
			   << " " <<  TDS_helper::destination(*fit)->degree() << std::endl);
	  
	} 
	CGAL_exactness_assertion(TDS_helper::get_undirected_edge_label(*fit) != Event_key());
      }
    }

  }

CGAL_KINETIC_END_NAMESPACE
#endif