// -*- c++ -*-
#ifndef HUGO_LEDA_GRAPH_WRAPPER_H
#define HUGO_LEDA_GRAPH_WRAPPER_H

#include <LEDA/graph.h>
#include <LEDA/node_array.h>
#include <LEDA/edge_array.h>
#include <LEDA/node_map.h>
#include <LEDA/edge_map.h>
//#include <LEDA/graph_alg.h>
//#include <LEDA/dimacs.h>

//#if defined(LEDA_NAMESPACE)
//using namespace leda;
//#endif

#include <invalid.h>

/// The namespace of HugoLib
namespace hugo {

  // @defgroup empty_graph The LedaGraphWrapper class
  // @{

  /// An empty graph class.
  
  /// This class provides all the common features of a grapf structure,
  /// however completely without implementations or real data structures
  /// behind the interface.
  /// All graph algorithms should compile with this class, but it will not
  /// run properly, of course.
  ///
  /// It can be used for checking the interface compatibility,
  /// or it can serve as a skeleton of a new graph structure.
  /// 
  /// Also, you will find here the full documentation of a certain graph
  /// feature, the documentation of a real graph imlementation
  /// like @ref ListGraph or
  /// @ref SmartGraph will just refer to this structure.
  template<typename Graph>
  class LedaGraphWrapper
  {
    Graph* _graph;
  public:
   
        //LedaGraphWrapper() { }
    LedaGraphWrapper(Graph& __graph) : _graph(&__graph) { }
    LedaGraphWrapper(const LedaGraphWrapper &G) : _graph(G._graph) { }

    template <typename T> class NodeMap;
    template <typename T> class EdgeMap;

    /// The base type of the node iterators.
    class Node {
      friend class LedaGraphWrapper;
      //friend class Edge;
      friend class EdgeIt;
      friend class InEdgeIt;
      friend class OutEdgeIt;
    protected:
      template <typename T> friend class NodeMap;
      leda_node _n;
      Node(leda_node __n) : _n(__n) { } 
    public:
      /// @warning The default constructor sets the iterator
      /// to an undefined value.
      Node() {}   //FIXME
      /// Initialize the iterator to be invalid
      Node(Invalid) : _n(0) { }
      //Node(const Node &) {} 
      bool operator==(Node n) const { return _n==n._n; } //FIXME
      bool operator!=(Node n) const { return _n!=n._n; } //FIXME
      operator leda_node () { return _n; }
    };
    
    /// This iterator goes through each node.
    class NodeIt : public Node {
    public:
      /// @warning The default constructor sets the iterator
      /// to an undefined value.
      NodeIt() {} //FIXME
      /// Initialize the iterator to be invalid
      NodeIt(Invalid i) : Node(i) {}
      /// Sets the iterator to the first node of \c G.
      NodeIt(const LedaGraphWrapper &G) : Node(G._graph->first_node()) { }
      //NodeIt(const NodeIt &) {} //FIXME
    };
    
    /// The base type of the edge iterators.
    class Edge {
      friend class LedaGraphWrapper;
    protected:
      template <typename T> friend class EdgeMap;
      leda_edge _e;
      Edge(leda_edge __e) : _e(__e) { } 
    public:
      /// @warning The default constructor sets the iterator
      /// to an undefined value.
      Edge() {}   //FIXME
      /// Initialize the iterator to be invalid
      Edge(Invalid) : _e(0) {}
      //Edge(const Edge &) {} 
      bool operator==(Edge e) const { return _e==e._e; } //FIXME
      bool operator!=(Edge e) const { return _e!=e._e; } //FIXME 
      operator leda_edge () { return _e; }
    };
    
    /// This iterator goes trought the outgoing edges of a certain graph.
    
    class OutEdgeIt : public Edge {
    public:
      /// @warning The default constructor sets the iterator
      /// to an undefined value.
      OutEdgeIt() {}
      /// Initialize the iterator to be invalid
      OutEdgeIt(Invalid i) : Edge(i) {}
      /// This constructor sets the iterator to first outgoing edge.
    
      /// This constructor set the iterator to the first outgoing edge of
      /// node
      ///@param n the node
      ///@param G the graph
      OutEdgeIt(const LedaGraphWrapper & G, Node n) : Edge(G._graph->first_adj_edge(n._n)) { }
    };

    class InEdgeIt : public Edge {
    public:
      /// @warning The default constructor sets the iterator
      /// to an undefined value.
      InEdgeIt() {}
      /// Initialize the iterator to be invalid
      InEdgeIt(Invalid i) : Edge(i) {}
      InEdgeIt(const LedaGraphWrapper & G, Node n) : Edge(G._graph->first_in_edge(n._n)) { }
    };

    //  class SymEdgeIt : public Edge {};
    class EdgeIt : public Edge {
    public:
      /// @warning The default constructor sets the iterator
      /// to an undefined value.
      EdgeIt() {}
      /// Initialize the iterator to be invalid
      EdgeIt(Invalid i) : Edge(i) {}
      EdgeIt(const LedaGraphWrapper & G) : Edge(G._graph->first_edge()) { }
    };

    /// First node of the graph.

    /// \post \c i and the return value will be the first node.
    ///
    NodeIt &first(NodeIt &i) const { i=NodeIt(*this); return i; }

    /// The first outgoing edge.
    InEdgeIt &first(InEdgeIt &i, Node n) const { 
      i=InEdgeIt(*this, n); 
      return i;
    }
    /// The first incoming edge.
    OutEdgeIt &first(OutEdgeIt &i, Node n) const { 
      i=OutEdgeIt(*this, n); 
      return i;
    }
    //  SymEdgeIt &first(SymEdgeIt &, Node) const { return i;}
    /// The first edge of the Graph.
    EdgeIt &first(EdgeIt &i) const {      
      i=EdgeIt(*this); 
      return i; }

//     Node getNext(Node) const {}
//     InEdgeIt getNext(InEdgeIt) const {}
//     OutEdgeIt getNext(OutEdgeIt) const {}
//     //SymEdgeIt getNext(SymEdgeIt) const {}
//     EdgeIt getNext(EdgeIt) const {}

    /// Go to the next node.
    NodeIt &next(NodeIt &i) const { 
      i._n=_graph->succ_node(i._n); 
      return i; 
    }
    /// Go to the next incoming edge.
    InEdgeIt &next(InEdgeIt &i) const { 
      i._e=_graph->in_succ(i._e); 
      return i;
    }
    /// Go to the next outgoing edge.
    OutEdgeIt &next(OutEdgeIt &i) const { 
      i._e=_graph->adj_succ(i._e); 
      return i;
    }
    //SymEdgeIt &next(SymEdgeIt &) const {}
    /// Go to the next edge.
    EdgeIt &next(EdgeIt &i) const {      
      i._e=_graph->succ_edge(i._e); 
      return i; 
    }

    template< typename It >
    It first() const { 
      It e;
      first(e);
      return e; 
    }

    template< typename It >
    It first(Node v) const { 
      It e;
      first(e, v);
      return e; 
    }

    ///Gives back the head node of an edge.
    Node head(Edge e) const { 
      return Node(_graph->target(e._e)); 
    }
    ///Gives back the tail node of an edge.
    Node tail(Edge e) const { 
      return Node(_graph->source(e._e)); 
    }
  
    Node aNode(InEdgeIt e) const { return head(e); }
    Node aNode(OutEdgeIt e) const { return tail(e); }
    //   Node aNode(SymEdgeIt) const {}

    Node bNode(InEdgeIt e) const { return tail(e); }
    Node bNode(OutEdgeIt e) const { return head(e); }
    //   Node bNode(SymEdgeIt) const {}

    /// Checks if a node iterator is valid
    bool valid(Node n) const { return n._n; }
    /// Checks if an edge iterator is valid
    bool valid(Edge e) const { return e._e; }

    ///Gives back the \e id of a node.
    int id(Node n) const { return n._n->id(); }
    ///Gives back the \e id of an edge.
    int id(Edge e) const { return e._e->id(); }

    //void setInvalid(Node &) const {};
    //void setInvalid(Edge &) const {};
  
    Node addNode() const { return Node(_graph->new_node()); }
    Edge addEdge(Node tail, Node head) const { 
      return Edge(_graph->new_edge(tail._n, head._n));
    }
    
    void erase(Node n) const { _graph->del_node(n._n); }
    void erase(Edge e) const { _graph->del_edge(e._e); }

    void clear() const { _graph->clear(); }

    int nodeNum() const { return _graph->number_of_nodes(); }
    int edgeNum() const { return _graph->number_of_edges(); }

    ///Read/write map from the nodes to type \c T.
    template<typename T> class NodeMap
    {
      leda_node_map<T> leda_stuff;
    public:
      typedef T ValueType;
      typedef Node KeyType;

      NodeMap(const LedaGraphWrapper &G) : leda_stuff(*(G._graph)) {}
      NodeMap(const LedaGraphWrapper &G, T t) : leda_stuff(*(G._graph), t) {}

      void set(Node i, T t) { leda_stuff[i._n]=t; }
      T get(Node i) const { return leda_stuff[i._n]; }  //FIXME: Is it necessary
      T &operator[](Node i) { return leda_stuff[i._n]; }
      const T &operator[](Node i) const { return leda_stuff[i._n]; }

      void update() { /*leda_stuff.init(leda_stuff.get_graph());*/ }
      //void update(T a) { leda_stuff.init(leda_stuff.get_graph()/**(G._graph)*/, a); }   //FIXME: Is it necessary
    };

    ///Read/write map from the edges to type \c T.
    template<typename T> class EdgeMap
    {
      leda_edge_map<T> leda_stuff;
    public:
      typedef T ValueType;
      typedef Edge KeyType;

      EdgeMap(const LedaGraphWrapper &G) : leda_stuff(*(G._graph)) {}
      EdgeMap(const LedaGraphWrapper &G, T t) : leda_stuff(*(G._graph), t) {}

      void set(Edge i, T t) { leda_stuff[i._e]=t; }
      T get(Edge i) const { return leda_stuff[i._e]; }  //FIXME: Is it necessary
      T &operator[](Edge i) { return leda_stuff[i._e]; }
      const T &operator[](Edge i) const { return leda_stuff[i._e]; }

      void update() { /*leda_stuff.init(leda_stuff.get_graph());*/ }
      //void update(T a) { leda_stuff.init(leda_stuff.get_graph()/**(G._graph)*/, a); }   //FIXME: Is it necessary
    };

  };

  // @}

} //namespace hugo



// class EmptyBipGraph : public EmptyGraph
// {
//   class ANode {};
//   class BNode {};

//   ANode &next(ANode &) {}
//   BNode &next(BNode &) {}

//   ANode &getFirst(ANode &) const {}
//   BNode &getFirst(BNode &) const {}

//   enum NodeClass { A = 0, B = 1 };
//   NodeClass getClass(Node n) {}

// }

#endif // HUGO_LEDA_GRAPH_WRAPPER_H