// -*- c++ -*-

#ifndef HUGO_LEDA_GRAPH_H

#define HUGO_LEDA_GRAPH_H

#include <LEDA/graph.h>

#include <LEDA/node_array.h>

#include <LEDA/edge_array.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 LedaGraph 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 LedaGraph

  {

    Graph* _graph;

  public:

        //LedaGraph() { }

    LedaGraph(Graph& __graph) : _graph(&__graph) { }

    LedaGraph(const LedaGraph &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 LedaGraph;

      //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

    };

    /// 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 LedaGraph &G) : Node(G._graph->first_node()) { }

      //NodeIt(const NodeIt &) {} //FIXME

    };

    /// The base type of the edge iterators.

    class Edge {

      friend class LedaGraph;

    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    

    };

    /// 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 LedaGraph & 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 LedaGraph & 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 LedaGraph & 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 LedaGraph &G) : leda_stuff(*(G._graph)) {}

      NodeMap(const LedaGraph &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 LedaGraph &G) : leda_stuff(*(G._graph)) {}

      EdgeMap(const LedaGraph &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_H