source: lemon-0.x/src/work/marci/merge_node_graph_wrapper.h @ 915:751ed145bdae

/* -*- C++ -*-
 * src/hugo/graph_wrapper.h - Part of HUGOlib, 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.
 *
 */

#include <hugo/invalid.h>
#include <hugo/maps.h>
#include <hugo/map_defines.h>
#include <hugo/graph_wrapper.h>
#include <iostream>

#ifndef HUGO_MERGE_NODE_GRAPH_WRAPPER_H
#define HUGO_MERGE_NODE_GRAPH_WRAPPER_H

namespace hugo {

  template <typename Graph1, typename Graph2> 
  class MergeNodeGraphWrapper : 
    public GraphWrapper<Graph1>, public GraphWrapper<Graph2> {
    typedef GraphWrapper<Graph1> Parent1;
    typedef GraphWrapper<Graph2> Parent2;
    typedef typename GraphWrapper<Graph1>::Node Graph1Node;
    typedef typename GraphWrapper<Graph2>::Node Graph2Node;
  public:
    class Node;
    class NodeIt;
    friend class Node;
    friend class NodeIt;

    MergeNodeGraphWrapper(Graph1& _graph1, Graph2& _graph2) : 
      Parent1(_graph1), Parent2(_graph2) { }

    class Node : public Graph1Node, public Graph2Node {
      friend class MergeNodeGraphWrapper<Graph1, Graph2>;
      //template<typename T> 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));
      }
    };

    class NodeIt : public Node {
      friend class MergeNodeGraphWrapper<Graph1, Graph2>;
    protected:
      const MergeNodeGraphWrapper<Graph1, Graph2>* gw;
    public:
      NodeIt() { }
      NodeIt(Invalid i) : Node(i) { }
      NodeIt(const MergeNodeGraphWrapper<Graph1, Graph2>& _gw) : 
        Node(typename Graph1::NodeIt(*_gw.Parent1::graph), 
             typename Graph2::NodeIt(),
             false), gw(&_gw) { 
        if (*static_cast<Graph1Node*>(this)==INVALID) {
          *static_cast<Node*>(this)=
            Node(Graph1Node(INVALID), 
                 typename Graph2::NodeIt(*_gw.Parent2::graph), 
                 true);
        }
      }
      NodeIt(const MergeNodeGraphWrapper<Graph1, Graph2>& _gw, 
             const Node& n) : 
        Node(n), gw(&_gw) { }
      NodeIt& operator++() { 
        if (!this->backward) {
          *(static_cast<Graph1Node*>(this))=
            ++(typename Graph1::NodeIt(*gw->Parent1::graph, *this));
          if (*static_cast<Graph1Node*>(this)==INVALID) {
            *static_cast<Node*>(this)=
              Node(typename Graph1::Node(INVALID), 
                   typename Graph2::NodeIt(*gw->Parent2::graph), true);
          }
        } else {
          *(static_cast<Graph2Node*>(this))=
            ++(typename Graph2::NodeIt(*gw->Parent2::graph, *this));
        }
        return *this;
      }
    };

    int id(const Node& n) const { 
      if (!n.backward) 
        return this->Parent1::graph->id(n);
      else
        return this->Parent2::graph->id(n);
    }

  };

} //namespace hugo

#endif //HUGO_MERGE_NODE_GRAPH_WRAPPER_H