/* -*- C++ -*-

 * src/lemon/merge_node_graph_wrapper.h - Part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Combinatorial Optimization Research Group, EGRES).

 *

 * Permission to use, modify and distribute this software is granted

 * provided that this copyright notice appears in all copies. For

 * precise terms see the accompanying LICENSE file.

 *

 * This software is provided "AS IS" with no warranty of any kind,

 * express or implied, and with no claim as to its suitability for any

 * purpose.

 *

 */

#ifndef LEMON_MERGE_NODE_GRAPH_WRAPPER_H

#define LEMON_MERGE_NODE_GRAPH_WRAPPER_H

#include <lemon/invalid.h>

#include <lemon/maps.h>

#include <lemon/map_defines.h>

#include <lemon/graph_wrapper.h>

#include <iostream>

using std::cout;

using std::endl;

#include <boost/type_traits.hpp>

#include <boost/utility/enable_if.hpp>

namespace lemon {

  template <class _Graph1>

  class P1 : public GraphWrapperBase<_Graph1> {

  };

  template <class _Graph2>

  class P2 : public GraphWrapperBase<_Graph2> {

  };

  template <typename _Graph1, typename _Graph2, typename Enable=void>

  class MergeNodeGraphWrapperBaseBase : 

    public P1<_Graph1>, public P2<_Graph2> {

  public:

    static void printNode() { std::cout << "node: generic" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef P1<_Graph1> Parent1;

    typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

  protected:

    MergeNodeGraphWrapperBaseBase() { }

  public:

    class Node : public Graph1Node, public Graph2Node {

      friend class MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Node() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Node(const Graph1Node& n1, 

	   const Graph2Node& n2, bool _backward) : 

	Graph1Node(n1), Graph2Node(n2), backward(_backward) { }

      Node(Invalid i) : Graph1Node(i), Graph2Node(i), backward(true) { }

      bool operator==(const Node& v) const { 

	if (backward) 

	  return (v.backward && 

		  static_cast<Graph2Node>(*this)==static_cast<Graph2Node>(v)); 

	else 

	  return (!v.backward && 

		  static_cast<Graph1Node>(*this)==static_cast<Graph1Node>(v)); 

      } 

      bool operator!=(const Node& v) const { 

	return !(*this==v);

      }

    };

    static bool forward(const Node& n) { return !n.backward; }

    static bool backward(const Node& n) { return n.backward; }

    static void setForward(Node& n) { n.backward=false; }

    static void setBackward(Node& n) { n.backward=true; }    

  };

  template <typename _Graph1, typename _Graph2>

  class MergeNodeGraphWrapperBaseBase<

    _Graph1, _Graph2, typename boost::enable_if<

    boost::is_same<typename _Graph1::Node, typename _Graph2::Node> >::type> : 

    public P1<_Graph1>, public P2<_Graph2> {

  public:

    static void printNode() { std::cout << "node: same" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef P1<_Graph1> Parent1;

    typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

  protected:

    MergeNodeGraphWrapperBaseBase() { }

  public:

    class Node : public Graph1Node {

      friend class MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Node() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Node(const Graph1Node& n1, 

	   const Graph2Node& n2, bool _backward) : 

	Graph1Node(!_backward ? n1 : n2), backward(_backward) { }

      Node(Invalid i) : Graph1Node(i), backward(true) { }

      bool operator==(const Node& v) const { 

	return (backward==v.backward && 

		static_cast<Graph1Node>(*this)==static_cast<Graph1Node>(v));

      } 

      bool operator!=(const Node& v) const { 

	return !(*this==v);

      }

    };

    static bool forward(const Node& n) { return !n.backward; }

    static bool backward(const Node& n) { return n.backward; }

    static void setForward(Node& n) { n.backward=false; }

    static void setBackward(Node& n) { n.backward=true; }

  };

  template <typename _Graph1, typename _Graph2>

  class MergeNodeGraphWrapperBaseBase<

    _Graph1, _Graph2, typename boost::enable_if<

    boost::is_base_and_derived<typename _Graph1::Node, typename _Graph2::Node> >::type> : 

    public P1<_Graph1>, public P2<_Graph2> {

  public :

    static void printNode() { std::cout << "node: 2nd is derived" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef P1<_Graph1> Parent1;

    typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

  protected:

    MergeNodeGraphWrapperBaseBase() { }

  public:

    class Node : public Graph2Node {

      friend class MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Node() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Node(const Graph1Node& n1, 

	   const Graph2Node& n2, bool _backward) : 

	Graph2Node(n2), backward(_backward) { 

	if (!backward) *this=n1;

      }

      Node(Invalid i) : Graph2Node(i), backward(true) { }

      bool operator==(const Node& v) const { 

	if (backward) 

	  return (v.backward && 

		  static_cast<Graph2Node>(*this)==static_cast<Graph2Node>(v)); 

	else 

	  return (!v.backward && 

		  static_cast<Graph1Node>(*this)==static_cast<Graph1Node>(v)); 

      } 

      bool operator!=(const Node& v) const { 

	return !(*this==v);

      }

    };

    static bool forward(const Node& n) { return !n.backward; }

    static bool backward(const Node& n) { return n.backward; }

    static void setForward(Node& n) { n.backward=false; }

    static void setBackward(Node& n) { n.backward=true; }

  };

  template <typename _Graph1, typename _Graph2>

  class MergeNodeGraphWrapperBaseBase<

    _Graph1, _Graph2, typename boost::enable_if<

    boost::is_base_and_derived<typename _Graph2::Node, typename _Graph1::Node> >::type> : 

    public P1<_Graph1>, public P2<_Graph2> {

  public :

    static void printNode() { std::cout << "node: 1st is derived" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef P1<_Graph1> Parent1;

    typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

  protected:

    MergeNodeGraphWrapperBaseBase() { }

  public:

    class Node : public Graph1Node {

      friend class MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Node() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Node(const Graph1Node& n1, 

	   const Graph2Node& n2, bool _backward) : 

	Graph1Node(n1), backward(_backward) { 

	if (backward) *this=n2;

      }

      Node(Invalid i) : Graph1Node(i), backward(true) { }

      bool operator==(const Node& v) const { 

	if (backward) 

	  return (v.backward && 

		  static_cast<Graph2Node>(*this)==static_cast<Graph2Node>(v)); 

	else 

	  return (!v.backward && 

		  static_cast<Graph1Node>(*this)==static_cast<Graph1Node>(v)); 

      } 

      bool operator!=(const Node& v) const { 

	return !(*this==v);

      }

    };

    static bool forward(const Node& n) { return !n.backward; }

    static bool backward(const Node& n) { return n.backward; }

    static void setForward(Node& n) { n.backward=false; }

    static void setBackward(Node& n) { n.backward=true; }

  };

  template <typename _Graph1, typename _Graph2>

  class MergeNodeGraphWrapperBase : 

    public MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2> {

  public:

    typedef MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2> Parent;

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef P1<_Graph1> Parent1;

    typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

    typedef typename Parent::Node Node; 

    class Edge { };

    void first(Node& i) const {

      Parent1::graph->first(*static_cast<Graph1Node*>(&i));

      this->setForward(i);

      if (*static_cast<Graph1Node*>(&i)==INVALID) {

	Parent2::graph->first(*static_cast<Graph2Node*>(&i));

	this->setBackward(i);

      }

    }

    void next(Node& i) const {

      if (this->forward(i)) {

	Parent1::graph->next(*static_cast<Graph1Node*>(&i));

	if (*static_cast<Graph1Node*>(&i)==INVALID) {

	  Parent2::graph->first(*static_cast<Graph2Node*>(&i));

	  this->setBackward(i);

	}

      } else {

	Parent2::graph->next(*static_cast<Graph2Node*>(&i));

      }

    }

    int id(const Node& n) const { 

      if (this->forward(n)) 

	return this->Parent1::graph->id(n);

      else

	return this->Parent2::graph->id(n);

    }

    template <typename _Value> 

    class NodeMap { 

    protected:

      typedef typename _Graph1::template NodeMap<_Value> ParentMap1;

      typedef typename _Graph2::template NodeMap<_Value> ParentMap2;

      ParentMap1 forward_map;

      ParentMap2 backward_map;

    public:

      typedef _Value Value;

      typedef Node Key;

      NodeMap(const MergeNodeGraphWrapperBase<_Graph1, _Graph2>& gw) : 

	forward_map(*(gw.Parent1::graph)), 

	backward_map(*(gw.Parent2::graph)) { }

      NodeMap(const MergeNodeGraphWrapperBase<_Graph1, _Graph2>& gw, 

	      const _Value& value) : 

	forward_map(*(gw.Parent1::graph), value), 

	backward_map(*(gw.Parent2::graph), value) { }

      _Value operator[](const Node& n) const {

	if (Parent::forward(n)) 

	  return forward_map[n];

	else 

	  return backward_map[n];

      }

      void set(const Node& n, const _Value& value) {

	if (Parent::forward(n)) 

	  forward_map.set(n, value);

	else 

	  backward_map.set(n, value);

      }

//       using ParentMap1::operator[];

//       using ParentMap2::operator[];

    };

  };

  /*! A graph wrapper class 

    for merging the node-set of two node-disjoint graphs 

    into the node-set of one graph. 

    Different implementations are according to the relation of 

    _Graph1::Node and _Graph2::Node. 

    If _Graph1::Node and _Graph2::Node are unrelated, then 

    MergeNodeGraphWrapper<_Graph1, _Graph2>::Node 

    is derived from both. 

    If _Graph1::Node and _Graph2::Node are the same type, then 

    MergeNodeGraphWrapper<_Graph1, _Graph2>::Node 

    is derived from _Graph1::Node. 

    If one of _Graph1::Node and _Graph2::Node 

    is derived from the other one, then 

    MergeNodeGraphWrapper<_Graph1, _Graph2>::Node 

    is derived from the derived type.

    It does not satisfy 

    StaticGraph concept as it has no edge-set which 

    works together with the node-set.

  */

  template <typename _Graph1, typename _Graph2>

  class MergeNodeGraphWrapper : public 

  IterableGraphExtender<MergeNodeGraphWrapperBase<_Graph1, _Graph2> > {

  public:

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef IterableGraphExtender<

      MergeNodeGraphWrapperBase<_Graph1, _Graph2> > Parent;

  protected:

    MergeNodeGraphWrapper() { }

  public:

    MergeNodeGraphWrapper(_Graph1& _graph1, _Graph2& _graph2) { 

      Parent::Parent1::setGraph(_graph1);

      Parent::Parent2::setGraph(_graph2);

    }

  };

  /*! A grah wrapper base class 

    for merging the node-sets and edge-sets of 

    two node-disjoint graphs 

    into one graph.

    Generic implementation for unrelated _Graph1::Edge and _Graph2::Edge.

   */

  template <typename _Graph1, typename _Graph2, typename Enable=void>

  class MergeEdgeGraphWrapperBaseBase : 

    public MergeNodeGraphWrapperBase<_Graph1, _Graph2> {

  public:

    static void printEdge() { std::cout << "edge: generic" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef MergeNodeGraphWrapperBase<_Graph1, _Graph2> Parent;

    typedef typename Parent::Parent1 Parent1;

    typedef typename Parent::Parent2 Parent2;

//     typedef P1<_Graph1> Parent1;

//     typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Edge Graph1Edge;

    typedef typename Parent2::Edge Graph2Edge;

  protected:

    MergeEdgeGraphWrapperBaseBase() { }

  public:

    class Edge : public Graph1Edge, public Graph2Edge {

      friend class MergeEdgeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Edge() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Edge(const Graph1Edge& n1, 

	   const Graph2Edge& n2, bool _backward) : 

	Graph1Edge(n1), Graph2Edge(n2), backward(_backward) { }

      Edge(Invalid i) : Graph1Edge(i), Graph2Edge(i), backward(true) { }

      bool operator==(const Edge& v) const { 

	if (backward) 

	  return (v.backward && 

		  static_cast<Graph2Edge>(*this)==static_cast<Graph2Edge>(v)); 

	else 

	  return (!v.backward && 

		  static_cast<Graph1Edge>(*this)==static_cast<Graph1Edge>(v)); 

      } 

      bool operator!=(const Edge& v) const { 

	return !(*this==v);

      }

    };

    using Parent::forward;

    using Parent::backward;

    using Parent::setForward;

    using Parent::setBackward;

    static bool forward(const Edge& e) { return !e.backward; }

    static bool backward(const Edge& e) { return e.backward; }

    static void setForward(Edge& e) { e.backward=false; }

    static void setBackward(Edge& e) { e.backward=true; }

  };

  /*! A graph wrapper base class 

    for merging the node-sets and edge-sets of 

    two node-disjoint graphs 

    into one graph.

    Specialization for the case when _Graph1::Edge and _Graph2::Edge

    are the same.

   */

  template <typename _Graph1, typename _Graph2>

  class MergeEdgeGraphWrapperBaseBase<

    _Graph1, _Graph2, typename boost::enable_if<

    boost::is_same<typename _Graph1::Edge, typename _Graph2::Edge> >::type> : 

    public MergeNodeGraphWrapperBase<_Graph1, _Graph2> {

  public:

    static void printEdge() { std::cout << "edge: same" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef MergeNodeGraphWrapperBase<_Graph1, _Graph2> Parent;

    typedef typename Parent::Parent1 Parent1;

    typedef typename Parent::Parent2 Parent2;

//     typedef P1<_Graph1> Parent1;

//     typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Edge Graph1Edge;

    typedef typename Parent2::Edge Graph2Edge;

  protected:

    MergeEdgeGraphWrapperBaseBase() { }

  public:

    class Edge : public Graph1Edge {

      friend class MergeEdgeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Edge() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Edge(const Graph1Edge& n1, 

	   const Graph2Edge& n2, bool _backward) : 

	Graph1Edge(!_backward ? n1 : n2), backward(_backward) { }

      Edge(Invalid i) : Graph1Edge(i), backward(true) { }

      bool operator==(const Edge& v) const { 

	return (backward==v.backward && 

		static_cast<Graph1Edge>(*this)==static_cast<Graph1Edge>(v)); 

      }

      bool operator!=(const Edge& v) const { 

	return !(*this==v);

      }

    };

    using Parent::forward;

    using Parent::backward;

    using Parent::setForward;

    using Parent::setBackward;

    static bool forward(const Edge& e) { return !e.backward; }

    static bool backward(const Edge& e) { return e.backward; }

    static void setForward(Edge& e) { e.backward=false; }

    static void setBackward(Edge& e) { e.backward=true; }

  };

  /*! A grah wrapper base class 

    for merging the node-sets and edge-sets of 

    two node-disjoint graphs 

    into one graph. 

    Specialized implementation for the case 

    when _Graph1::Edge is a base class and _Graph2::Edge

    is derived from it.

   */

  template <typename _Graph1, typename _Graph2>

  class MergeEdgeGraphWrapperBaseBase<

    _Graph1, _Graph2, typename boost::enable_if<

    boost::is_base_and_derived<typename _Graph1::Edge, typename _Graph2::Edge> >::type> : 

    public MergeNodeGraphWrapperBase<_Graph1, _Graph2> {

  public:

    static void printEdge() { std::cout << "edge: 2nd is derived" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef MergeNodeGraphWrapperBase<_Graph1, _Graph2> Parent;

    typedef typename Parent::Parent1 Parent1;

    typedef typename Parent::Parent2 Parent2;

//     typedef P1<_Graph1> Parent1;

//     typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Edge Graph1Edge;

    typedef typename Parent2::Edge Graph2Edge;

  protected:

    MergeEdgeGraphWrapperBaseBase() { }

  public:

    class Edge : public Graph2Edge {

      friend class MergeEdgeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Edge() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Edge(const Graph1Edge& n1, 

	   const Graph2Edge& n2, bool _backward) : 

	Graph2Edge(n2), backward(_backward) { 

	if (!backward) *this=n1;

      }

      Edge(Invalid i) : Graph2Edge(i), backward(true) { }

      bool operator==(const Edge& v) const { 

	if (backward) 

	  return (v.backward && 

		  static_cast<Graph2Edge>(*this)==static_cast<Graph2Edge>(v)); 

	else 

	  return (!v.backward && 

		  static_cast<Graph1Edge>(*this)==static_cast<Graph1Edge>(v)); 

      } 

      bool operator!=(const Edge& v) const { 

	return !(*this==v);

      }

    };

    using Parent::forward;

    using Parent::backward;

    using Parent::setForward;

    using Parent::setBackward;

    static bool forward(const Edge& e) { return !e.backward; }

    static bool backward(const Edge& e) { return e.backward; }

    static void setForward(Edge& e) { e.backward=false; }

    static void setBackward(Edge& e) { e.backward=true; }

  };

  /*! A grah wrapper base class 

    for merging the node-sets and edge-sets of 

    two node-disjoint graphs 

    into one graph. 

    Specialized implementation for the case 

    when _Graph1::Edge is derived from _Graph2::Edge.

   */

  template <typename _Graph1, typename _Graph2>

  class MergeEdgeGraphWrapperBaseBase<

    _Graph1, _Graph2, typename boost::enable_if<

    boost::is_base_and_derived<typename _Graph2::Edge, typename _Graph1::Edge> >::type> : 

    public MergeNodeGraphWrapperBase<_Graph1, _Graph2> {

  public:

    static void printEdge() { std::cout << "edge: 1st is derived" << std::endl; }

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef MergeNodeGraphWrapperBaseBase<_Graph1, _Graph2> Parent;

    typedef typename Parent::Parent1 Parent1;

    typedef typename Parent::Parent2 Parent2;

//     typedef P1<_Graph1> Parent1;

//     typedef P2<_Graph2> Parent2;

    typedef typename Parent1::Edge Graph1Edge;

    typedef typename Parent2::Edge Graph2Edge;

  protected:

    MergeEdgeGraphWrapperBaseBase() { }

  public:

    class Edge : public Graph1Edge {

      friend class MergeEdgeGraphWrapperBaseBase<_Graph1, _Graph2>;

    protected:

      bool backward; //true, iff backward

    public:

      Edge() { }

      /// \todo =false is needed, or causes problems?

      /// If \c _backward is false, then we get an edge corresponding to the 

      /// original one, otherwise its oppositely directed pair is obtained.

      Edge(const Graph1Edge& n1, 

	   const Graph2Edge& n2, bool _backward) : 

	Graph1Edge(n1), backward(_backward) { 

	if (backward) *this=n2;

      }

      Edge(Invalid i) : Graph1Edge(i), backward(true) { }

      bool operator==(const Edge& v) const { 

	if (backward) 

	  return (v.backward && 

		  static_cast<Graph2Edge>(*this)==static_cast<Graph2Edge>(v)); 

	else 

	  return (!v.backward && 

		  static_cast<Graph1Edge>(*this)==static_cast<Graph1Edge>(v)); 

      } 

      bool operator!=(const Edge& v) const { 

	return !(*this==v);

      }

    };

    using Parent::forward;

    using Parent::backward;

    using Parent::setForward;

    using Parent::setBackward;

    static bool forward(const Edge& e) { return !e.backward; }

    static bool backward(const Edge& e) { return e.backward; }

    static void setForward(Edge& e) { e.backward=false; }

    static void setBackward(Edge& e) { e.backward=true; }

  };

  template <typename _Graph1, typename _Graph2>

  class MergeEdgeGraphWrapperBase : 

    public MergeEdgeGraphWrapperBaseBase<_Graph1, _Graph2> {

  public:

    typedef MergeEdgeGraphWrapperBaseBase<_Graph1, _Graph2> Parent;

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef typename Parent::Parent1 Parent1;

    typedef typename Parent::Parent2 Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

    typedef typename Parent1::Edge Graph1Edge;

    typedef typename Parent2::Edge Graph2Edge;

    typedef typename Parent::Node Node;

    typedef typename Parent::Edge Edge;

    using Parent::first;

    void first(Edge& i) const {

      Parent1::graph->first(*static_cast<Graph1Edge*>(&i));

      this->setForward(i);

      if (*static_cast<Graph1Edge*>(&i)==INVALID) {

	Parent2::graph->first(*static_cast<Graph2Edge*>(&i));

	this->setBackward(i);

      }

    }

    void firstIn(Edge& i, const Node& n) const {

      if (forward(n)) {

	Parent1::graph->firstIn(*static_cast<Graph1Edge*>(&i), n);

	if (*static_cast<Graph1Edge*>(&i)==INVALID) 

	  i=INVALID;

	else

	  this->setForward(i);

      } else {

	Parent2::graph->firstIn(*static_cast<Graph2Edge*>(&i), n);

	this->setBackward(i);

      }

    }

    void firstOut(Edge& i, const Node& n) const {

      if (forward(n)) {

	Parent1::graph->firstOut(*static_cast<Graph1Edge*>(&i), n);

	if (*static_cast<Graph1Edge*>(&i)==INVALID) 

	  i=INVALID;

	else

	  this->setForward(i);

      } else {

	Parent2::graph->firstOut(*static_cast<Graph2Edge*>(&i), n);

	this->setBackward(i);

      }

    }

    using Parent::next;

    void next(Edge& i) const {

      if (forward(i)) {

	Parent1::graph->next(*static_cast<Graph1Edge*>(&i));

	if (*static_cast<Graph1Edge*>(&i)==INVALID) {

	  Parent2::graph->first(*static_cast<Graph2Edge*>(&i));

	  this->setBackward(i);

	}

      } else {

	Parent2::graph->next(*static_cast<Graph2Edge*>(&i));

      }

    }

    void nextIn(Edge& i) const {

      if (forward(i)) {

	Parent1::graph->nextIn(*static_cast<Graph1Edge*>(&i));

 	if (*static_cast<Graph1Edge*>(&i)==INVALID) i=INVALID;

      } else {

	Parent2::graph->nextIn(*static_cast<Graph2Edge*>(&i));

      }

    }

    void nextOut(Edge& i) const {

      if (Parent::forward(i)) {

	Parent1::graph->nextOut(*static_cast<Graph1Edge*>(&i));

 	if (*static_cast<Graph1Edge*>(&i)==INVALID) i=INVALID;

      } else {

	Parent2::graph->nextOut(*static_cast<Graph2Edge*>(&i));

      }

    }

    Node source(const Edge& i) const {

      if (forward(i)) {

	return 

	  Node(Parent1::graph->source(i), INVALID, false);

      } else {

	return 

	  Node(INVALID, Parent2::graph->source(i), true);

      }

    }

    Node target(const Edge& i) const {

      if (forward(i)) {

	return 

	  Node(Parent1::graph->target(i), INVALID, false);

      } else {

	return 

	  Node(INVALID, Parent2::graph->target(i), true);

      }

    }

    using Parent::id;

    int id(const Edge& n) const { 

      if (forward(n)) 

	return this->Parent1::graph->id(n);

      else

	return this->Parent2::graph->id(n);

    }

    template <typename _Value> 

    class EdgeMap { 

    protected:

      typedef typename Parent::Graph1::template EdgeMap<_Value> ParentMap1;

      typedef typename Parent::Graph2::template EdgeMap<_Value> ParentMap2;

      ParentMap1 forward_map;

      ParentMap2 backward_map;

    public:

      typedef _Value Value;

      typedef Edge Key;

      EdgeMap(const MergeEdgeGraphWrapperBase<_Graph1, _Graph2>& gw) : 

	forward_map(*(gw.Parent1::graph)), 

	backward_map(*(gw.Parent2::graph)) { }

      EdgeMap(const MergeEdgeGraphWrapperBase<_Graph1, _Graph2>& gw, 

	      const _Value& value) : 

	forward_map(*(gw.Parent1::graph), value), 

	backward_map(*(gw.Parent2::graph), value) { }

      _Value operator[](const Edge& n) const {

	if (Parent::forward(n)) 

	  return forward_map[n];

	else 

	  return backward_map[n];

      }

      void set(const Edge& n, const _Value& value) {

	if (Parent::forward(n)) 

	  forward_map.set(n, value);

	else 

	  backward_map.set(n, value);

      }

//       using ParentMap1::operator[];

//       using ParentMap2::operator[];

    };

  };

  /*! A graph wrapper class 

    for merging two node-disjoint graphs 

    into one graph. 

    Different implementations are according to the relation of 

    _Graph1::Edge and _Graph2::Edge. 

    If _Graph1::Edge and _Graph2::Edge are unrelated, then 

    MergeEdgeGraphWrapper<_Graph1, _Graph2>::Edge 

    is derived from both. 

    If _Graph1::Edge and _Graph2::Edge are the same type, then 

    MergeEdgeGraphWrapper<_Graph1, _Graph2>::Edge 

    is derived from _Graph1::Edge. 

    If one of _Graph1::Edge and _Graph2::Edge 

    is derived from the other one, then 

    MergeEdgeGraphWrapper<_Graph1, _Graph2>::Edge 

    is derived from the derived type.

    It does not satisfy 

  */

  template <typename _Graph1, typename _Graph2>

  class MergeEdgeGraphWrapper : public 

  IterableGraphExtender<MergeEdgeGraphWrapperBase<_Graph1, _Graph2> > {

  public:

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef IterableGraphExtender<

      MergeEdgeGraphWrapperBase<_Graph1, _Graph2> > Parent;

  protected:

    MergeEdgeGraphWrapper() { }

  public:

    MergeEdgeGraphWrapper(_Graph1& _graph1, _Graph2& _graph2) { 

      Parent::Parent1::setGraph(_graph1);

      Parent::Parent2::setGraph(_graph2);

    }

  };

  /*! A graph wrapper base class for the following functionality.

    If a bijection is given between the node-sets of two graphs, 

    then the second one can be considered as a new edge-set 

    over th first node-set. 

   */

  template <typename _Graph, typename _EdgeSetGraph>

  class NewEdgeSetGraphWrapperBase : public GraphWrapperBase<_Graph> {

  public:

    typedef GraphWrapperBase<_Graph> Parent; 

    typedef _Graph Graph;

    typedef _EdgeSetGraph EdgeSetGraph;

    typedef typename _Graph::Node Node;

    typedef typename _EdgeSetGraph::Node ENode;

  protected:

    EdgeSetGraph* edge_set_graph;

    typename Graph::NodeMap<ENode>* e_node;

    typename EdgeSetGraph::NodeMap<Node>* n_node;

    void setEdgeSetGraph(EdgeSetGraph& _edge_set_graph) { 

      edge_set_graph=&_edge_set_graph; 

    }

    /// For each node of \c Graph, this gives a node of \c EdgeSetGraph .

    void setNodeMap(typename EdgeSetGraph::NodeMap<Node>& _n_node) { 

      n_node=&_n_node; 

    }

    /// For each node of \c EdgeSetGraph, this gives a node of \c Graph .

    void setENodeMap(typename Graph::NodeMap<ENode>& _e_node) { 

      e_node=&_e_node; 

    }

  public:

    class Edge : public EdgeSetGraph::Edge {

      typedef typename EdgeSetGraph::Edge Parent;

    public:

      Edge() { }

      Edge(const Parent& e) : Parent(e) { }

      Edge(Invalid i) : Parent(i) { }

    };

    using Parent::first;

    void first(Edge &e) const { 

      edge_set_graph->first(e);

    }

    void firstOut(Edge& e, const Node& n) const {

//       cout << e_node << endl;

//       cout << n_node << endl;

      edge_set_graph->firstOut(e, (*e_node)[n]);

    }

    void firstIn(Edge& e, const Node& n) const {

      edge_set_graph->firstIn(e, (*e_node)[n]);

    }

    using Parent::next;

    void next(Edge &e) const { 

      edge_set_graph->next(e);

    }

    void nextOut(Edge& e) const {

      edge_set_graph->nextOut(e);

    }

    void nextIn(Edge& e) const {

      edge_set_graph->nextIn(e);

    }

    Node source(const Edge& e) const { 

      return (*n_node)[edge_set_graph->source(e)];

    }

    Node target(const Edge& e) const { 

      return (*n_node)[edge_set_graph->target(e)];

    }

    int edgeNum() const { return edge_set_graph->edgeNum(); }

//     NNode addOldNode() {

//       return Parent::addNode();

//     }

//     ENode addNewNode() {

//       return edge_set_graph->addNode();

//     }

    Edge addEdge(const Node& u, const Node& v) {

      return edge_set_graph->addEdge((*e_node)[u], (*e_node)[v]);

    }

    using Parent::erase;

    void erase(const Edge& i) const { edge_set_graph->erase(i); }

    void clear() const { Parent::clear(); edge_set_graph->clear(); }

    bool forward(const Edge& e) const { return edge_set_graph->forward(e); }

    bool backward(const Edge& e) const { return edge_set_graph->backward(e); }

    int id(const Node& e) const { return Parent::id(e); }

    int id(const Edge& e) const { return edge_set_graph->id(e); }

    Edge opposite(const Edge& e) const { return edge_set_graph->opposite(e); }

    template <typename _Value>

    class EdgeMap : public EdgeSetGraph::EdgeMap<_Value> {

    public:

      typedef typename EdgeSetGraph::EdgeMap<_Value> Parent; 

      typedef _Value Value;

      typedef Edge Key;

      EdgeMap(const NewEdgeSetGraphWrapperBase& gw) : 

	Parent(*(gw.edge_set_graph)) { }

      EdgeMap(const NewEdgeSetGraphWrapperBase& gw, const _Value& _value) : 

	Parent(*(gw.edge_set_graph), _value) { }

    };

  };

  /*! A graph wrapper class for the following functionality.

    If a bijection is given between the node-sets of two graphs, 

    then the second one can be considered as a new edge-set 

    over th first node-set. 

   */

  template <typename _Graph, typename _EdgeSetGraph>

  class NewEdgeSetGraphWrapper : 

    public IterableGraphExtender<

    NewEdgeSetGraphWrapperBase<_Graph, _EdgeSetGraph> > {

  public:

    typedef _Graph Graph;

    typedef _EdgeSetGraph EdgeSetGraph;

    typedef IterableGraphExtender<

      NewEdgeSetGraphWrapperBase<_Graph, _EdgeSetGraph> > Parent;

  protected:

    NewEdgeSetGraphWrapper() { }

  public:

    NewEdgeSetGraphWrapper(_Graph& _graph, 

			   _EdgeSetGraph& _edge_set_graph, 

			   typename _Graph::

			   NodeMap<typename _EdgeSetGraph::Node>& _e_node, 

			   typename _EdgeSetGraph::

			   NodeMap<typename _Graph::Node>& _n_node) { 

      setGraph(_graph);

      setEdgeSetGraph(_edge_set_graph);

      setNodeMap(_n_node);

      setENodeMap(_e_node);

    }

  };

  /*! A graph wrapper class for the following functionality.

    The same as NewEdgeSetGrapWrapper, but the bijection and the graph of 

    new edges is andled inthe class.

   */

  template <typename _Graph, typename _EdgeSetGraph>

  class NewEdgeSetGraphWrapper2 : 

    public IterableGraphExtender<

    NewEdgeSetGraphWrapperBase<_Graph, _EdgeSetGraph> > {

  public:

    typedef _Graph Graph;

    typedef _EdgeSetGraph EdgeSetGraph;

    typedef IterableGraphExtender<

      NewEdgeSetGraphWrapperBase<_Graph, _EdgeSetGraph> > Parent;

  protected:

    _EdgeSetGraph _edge_set_graph;

    typename Graph::template NodeMap<typename EdgeSetGraph::Node> _e_node;

    typename EdgeSetGraph::template NodeMap<typename Graph::Node> _n_node;

    NewEdgeSetGraphWrapper2() { }

  public:

    typedef typename Graph::Node Node;

    //    typedef typename Parent::Edge Edge;

    NewEdgeSetGraphWrapper2(_Graph& _graph) : 

      _edge_set_graph(), 

      _e_node(_graph), _n_node(_edge_set_graph) { 

      setGraph(_graph);

      setEdgeSetGraph(_edge_set_graph);

      setNodeMap(_n_node); setENodeMap(_e_node);

      Node n;

      for (this->first(n); n!=INVALID; this->next(n)) {

	typename EdgeSetGraph::Node e=_edge_set_graph.addNode();

	_e_node.set(n, e);

	_n_node.set(e, n);

      }

    }

//     Node addNode() {

//       Node n=(*this).Parent::addNode();

//       typename EdgeSetGraph::Node e=_edge_set_graph.addNode();

//       _e_node.set(n, e);

//       _n_node.set(e, n);

//       return n;

//     }

  };

  /*! A graph wrapper base class 

    for merging graphs of type _Graph1 and _Graph2 

    which are given on the same node-set 

    (specially on the node-set of Graph1) 

    into one graph.

    In an other point of view, _Graph1 is extended with 

    the edge-set of _Graph2.

    \warning we need specialize dimplementations

    \todo we need specialize dimplementations

    \bug we need specialize dimplementations

   */

  template <typename _Graph1, typename _Graph2, typename Enable=void>

  class AugmentingGraphWrapperBase : 

    public P1<_Graph1> {

  public:

    void printAugment() const { std::cout << "generic" << std::endl; }