/* -*- 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>

namespace lemon {

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

  class MergeNodeGraphWrapperBase : 

    public GraphWrapperBase<_Graph1>, public GraphWrapperBase<_Graph2> {

  public:

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef GraphWrapperBase<_Graph1> Parent1;

    typedef GraphWrapperBase<_Graph2> Parent2;

    typedef typename Parent1::Node Graph1Node;

    typedef typename Parent2::Node Graph2Node;

  protected:

    MergeNodeGraphWrapperBase() { }

  public:

    template <typename _Value> class NodeMap;

    class Node : public Graph1Node, public Graph2Node {

      friend class MergeNodeGraphWrapperBase<_Graph1, _Graph2>;

      template <typename Value> friend class NodeMap;

    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 { 

	return (this->backward==v.backward && 

		static_cast<Graph1Node>(*this)==

		static_cast<Graph1Node>(v) && 

		static_cast<Graph2Node>(*this)==

		static_cast<Graph2Node>(v));

      } 

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

	return (this->backward!=v.backward || 

		static_cast<Graph1Node>(*this)!=

		static_cast<Graph1Node>(v) || 

		static_cast<Graph2Node>(*this)!=

		static_cast<Graph2Node>(v));

      }

    };

    //typedef void Edge;

    class Edge { };

    void first(Node& i) const {

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

      i.backward=false;

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

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

	i.backward=true;

      }

    }

    void next(Node& i) const {

      if (!(i.backward)) {

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

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

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

	  i.backward=true;

	}

      } else {

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

      }

    }

    int id(const Node& n) const { 

      if (!n.backward) 

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

      else

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

    }

    template <typename _Value> 

    class NodeMap : public Parent1::template NodeMap<_Value>, 

		    public Parent2::template NodeMap<_Value> { 

      typedef typename Parent1::template NodeMap<_Value> ParentMap1;

      typedef typename Parent2::template NodeMap<_Value> ParentMap2;

    public:

      typedef _Value Value;

      typedef Node Key;

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

	ParentMap1(gw), ParentMap2(gw) { }

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

	      const _Value& value) : 

	ParentMap1(gw, value), ParentMap2(gw, value) { }

//       NodeMap(const NodeMap& copy)

// 	: ParentMap1(copy), 

// 	  ParentMap2(copy) { }

//       template <typename TT>

//       NodeMap(const NodeMap<TT>& copy)

// 	: ParentMap1(copy),

// 	  ParentMap2(copy) { }

//       NodeMap& operator=(const NodeMap& copy) {

// 	ParentMap1::operator=(copy);

// 	ParentMap2::operator=(copy);

// 	return *this;

//       }

//       template <typename TT>

//       NodeMap& operator=(const NodeMap<TT>& copy) {

// 	ParentMap1::operator=(copy);

// 	ParentMap2::operator=(copy);

// 	return *this;

//       }

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

	if (!n.backward) 

	  return ParentMap1::operator[](n);

	else 

	  return ParentMap2::operator[](n);

      }

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

	if (!n.backward) 

	  ParentMap1::set(n, value);

	else 

	  ParentMap2::set(n, value);

      }

      using ParentMap1::operator[];

      using ParentMap2::operator[];

    };

  };

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

  class MergeNodeGraphWrapper : public 

  IterableGraphExtender<MergeNodeGraphWrapperBase<_Graph1, _Graph2, Enable> > {

  public:

    typedef _Graph1 Graph1;

    typedef _Graph2 Graph2;

    typedef IterableGraphExtender<

      MergeNodeGraphWrapperBase<_Graph1, _Graph2, Enable> > Parent;

  protected:

    MergeNodeGraphWrapper() { }

  public:

    MergeNodeGraphWrapper(_Graph1& _graph1, _Graph2& _graph2) { 

      Parent::Parent1::setGraph(_graph1);

      Parent::Parent2::setGraph(_graph2);

    }

  };

} //namespace lemon

#endif //LEMON_MERGE_NODE_GRAPH_WRAPPER_H