// -*- c++ -*-

#ifndef LEMON_ERASABLE_GRAPH_EXTENDER_H

#define LEMON_ERASABLE_GRAPH_EXTENDER_H

#include <lemon/invalid.h>

namespace lemon {

  template <typename _Base> 

  class ErasableGraphExtender : public _Base {

  public:

    typedef ErasableGraphExtender Graph;

    typedef _Base Parent;

    typedef typename Parent::Node Node;

    typedef typename Parent::Edge Edge;

    void erase(const Node& node) {

      Edge edge;

      Parent::firstOut(edge, node);

      while (edge != INVALID ) {

	erase(edge);

	Parent::firstOut(edge, node);

      } 

      Parent::firstIn(edge, node);

      while (edge != INVALID ) {

	erase(edge);

	Parent::firstIn(edge, node);

      }

      Parent::getNotifier(Node()).erase(node);

      Parent::erase(node);

    }

    void erase(const Edge& edge) {

      Parent::getNotifier(Edge()).erase(edge);

      Parent::erase(edge);

    }

  };

  template <typename _Base> 

  class ErasableUndirGraphExtender : public _Base {

  public:

    typedef ErasableUndirGraphExtender Graph;

    typedef _Base Parent;

    typedef typename Parent::Node Node;

    typedef typename Parent::UndirEdge UndirEdge;

    typedef typename Parent::Edge Edge;

    void erase(const Node& node) {

      Edge edge;

      Parent::firstOut(edge, node);

      while (edge != INVALID ) {

	erase(edge);

	Parent::firstOut(edge, node);

      } 

      Parent::getNotifier(Node()).erase(node);

      Parent::erase(node);

    }

    void erase(const UndirEdge& uedge) {

      Parent::getNotifier(Edge()).erase(Edge(uedge,true));

      Parent::getNotifier(Edge()).erase(Edge(uedge,false));

      Parent::getNotifier(UndirEdge()).erase(uedge);

      Parent::erase(uedge);

    }

  };

}

#endif