/* -*- C++ -*-

 * src/lemon/concept/graph.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_CONCEPT_GRAPH_H

#define LEMON_CONCEPT_GRAPH_H

///\ingroup graph_concepts

///\file

///\brief Declaration of Graph.

#include <lemon/invalid.h>

#include <lemon/concept/maps.h>

#include <lemon/concept_check.h>

#include <lemon/concept/graph_component.h>

namespace lemon {

  namespace concept {

    /// \addtogroup graph_concepts

    /// @{

//     /// An empty static graph class.

//     /// This class provides all the common features of a graph structure,

//     /// however completely without implementations and 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.

//     ///

//     /// \todo A pages describing the concept of concept description would

//     /// be nice.

//     class StaticGraph

//     {

//     public:

//       /// Defalult constructor.

//       /// Defalult constructor.

//       ///

//       StaticGraph() { }

//       ///Copy consructor.

// //       ///\todo It is not clear, what we expect from a copy constructor.

// //       ///E.g. How to assign the nodes/edges to each other? What about maps?

// //       StaticGraph(const StaticGraph& g) { }

//       /// The base type of node iterators, 

//       /// or in other words, the trivial node iterator.

//       /// This is the base type of each node iterator,

//       /// thus each kind of node iterator converts to this.

//       /// More precisely each kind of node iterator should be inherited 

//       /// from the trivial node iterator.

//       class Node {

//       public:

// 	/// Default constructor

// 	/// @warning The default constructor sets the iterator

// 	/// to an undefined value.

// 	Node() { }

// 	/// Copy constructor.

// 	/// Copy constructor.

// 	///

// 	Node(const Node&) { }

// 	/// Invalid constructor \& conversion.

// 	/// This constructor initializes the iterator to be invalid.

// 	/// \sa Invalid for more details.

// 	Node(Invalid) { }

// 	/// Equality operator

// 	/// Two iterators are equal if and only if they point to the

// 	/// same object or both are invalid.

// 	bool operator==(Node) const { return true; }

// 	/// Inequality operator

// 	/// \sa operator==(Node n)

// 	///

// 	bool operator!=(Node) const { return true; }

//       };

//       /// This iterator goes through each node.

//       /// This iterator goes through each node.

//       /// Its usage is quite simple, for example you can count the number

//       /// of nodes in graph \c g of type \c Graph like this:

//       /// \code

//       /// int count=0;

//       /// for (Graph::NodeIt n(g); n!=INVALID ++n) ++count;

//       /// \endcode

//       class NodeIt : public Node {

//       public:

// 	/// Default constructor

// 	/// @warning The default constructor sets the iterator

// 	/// to an undefined value.

// 	NodeIt() { }

// 	/// Copy constructor.

// 	/// Copy constructor.

// 	///

// 	NodeIt(const NodeIt&) { }

// 	/// Invalid constructor \& conversion.

// 	/// Initialize the iterator to be invalid.

// 	/// \sa Invalid for more details.

// 	NodeIt(Invalid) { }

// 	/// Sets the iterator to the first node.

// 	/// Sets the iterator to the first node of \c g.

// 	///

// 	NodeIt(const StaticGraph& g) { }

// 	/// Node -> NodeIt conversion.

// 	/// Sets the iterator to the node of \c g pointed by the trivial 

// 	/// iterator n.

// 	/// This feature necessitates that each time we 

// 	/// iterate the edge-set, the iteration order is the same.

// 	NodeIt(const StaticGraph& g, const Node& n) { }

// 	/// Next node.

// 	/// Assign the iterator to the next node.

// 	///

// 	NodeIt& operator++() { return *this; }

//       };

//       /// The base type of the edge iterators.

//       /// The base type of the edge iterators.

//       ///

//       class Edge {

//       public:

// 	/// Default constructor

// 	/// @warning The default constructor sets the iterator

// 	/// to an undefined value.

// 	Edge() { }

// 	/// Copy constructor.

// 	/// Copy constructor.

// 	///

// 	Edge(const Edge&) { }

// 	/// Initialize the iterator to be invalid.

// 	/// Initialize the iterator to be invalid.

// 	///

// 	Edge(Invalid) { }

// 	/// Equality operator

// 	/// Two iterators are equal if and only if they point to the

// 	/// same object or both are invalid.

// 	bool operator==(Edge) const { return true; }

// 	/// Inequality operator

// 	/// \sa operator==(Node n)

// 	///

// 	bool operator!=(Edge) const { return true; }

//       };

//       /// This iterator goes trough the outgoing edges of a node.

//       /// This iterator goes trough the \e outgoing edges of a certain node

//       /// of a graph.

//       /// Its usage is quite simple, for example you can count the number

//       /// of outgoing edges of a node \c n

//       /// in graph \c g of type \c Graph as follows.

//       /// \code

//       /// int count=0;

//       /// for (Graph::OutEdgeIt e(g, n); e!=INVALID; ++e) ++count;

//       /// \endcode

//       class OutEdgeIt : public Edge {

//       public:

// 	/// Default constructor

// 	/// @warning The default constructor sets the iterator

// 	/// to an undefined value.

// 	OutEdgeIt() { }

// 	/// Copy constructor.

// 	/// Copy constructor.

// 	///

// 	OutEdgeIt(const OutEdgeIt&) { }

// 	/// Initialize the iterator to be invalid.

// 	/// Initialize the iterator to be invalid.

// 	///

// 	OutEdgeIt(Invalid) { }

// 	/// 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 StaticGraph& g, const Node& n) { }

// 	/// Edge -> OutEdgeIt conversion

// 	/// Sets the iterator to the value of the trivial iterator \c e.

// 	/// This feature necessitates that each time we 

// 	/// iterate the edge-set, the iteration order is the same.

// 	OutEdgeIt(const StaticGraph& g, const Edge& e) { }

// 	///Next outgoing edge

// 	/// Assign the iterator to the next 

// 	/// outgoing edge of the corresponding node.

// 	OutEdgeIt& operator++() { return *this; }

//       };

//       /// This iterator goes trough the incoming edges of a node.

//       /// This iterator goes trough the \e incoming edges of a certain node

//       /// of a graph.

//       /// Its usage is quite simple, for example you can count the number

//       /// of outgoing edges of a node \c n

//       /// in graph \c g of type \c Graph as follows.

//       /// \code

//       /// int count=0;

//       /// for(Graph::InEdgeIt e(g, n); e!=INVALID; ++e) ++count;

//       /// \endcode

//       class InEdgeIt : public Edge {

//       public:

// 	/// Default constructor

// 	/// @warning The default constructor sets the iterator

// 	/// to an undefined value.

// 	InEdgeIt() { }

// 	/// Copy constructor.

// 	/// Copy constructor.

// 	///

// 	InEdgeIt(const InEdgeIt&) { }

// 	/// Initialize the iterator to be invalid.

// 	/// Initialize the iterator to be invalid.

// 	///

// 	InEdgeIt(Invalid) { }

// 	/// This constructor sets the iterator to first incoming edge.

// 	/// This constructor set the iterator to the first incoming edge of

// 	/// node

// 	///@param n the node

// 	///@param g the graph

// 	InEdgeIt(const StaticGraph& g, const Node& n) { }

// 	/// Edge -> InEdgeIt conversion

// 	/// Sets the iterator to the value of the trivial iterator \c e.

// 	/// This feature necessitates that each time we 

// 	/// iterate the edge-set, the iteration order is the same.

// 	InEdgeIt(const StaticGraph& g, const Edge& n) { }

// 	/// Next incoming edge

// 	/// Assign the iterator to the next inedge of the corresponding node.

// 	///

// 	InEdgeIt& operator++() { return *this; }

//       };

//       /// This iterator goes through each edge.

//       /// This iterator goes through each edge of a graph.

//       /// Its usage is quite simple, for example you can count the number

//       /// of edges in a graph \c g of type \c Graph as follows:

//       /// \code

//       /// int count=0;

//       /// for(Graph::EdgeIt e(g); e!=INVALID; ++e) ++count;

//       /// \endcode

//       class EdgeIt : public Edge {

//       public:

// 	/// Default constructor

// 	/// @warning The default constructor sets the iterator

// 	/// to an undefined value.

// 	EdgeIt() { }

// 	/// Copy constructor.

// 	/// Copy constructor.

// 	///

// 	EdgeIt(const EdgeIt&) { }

// 	/// Initialize the iterator to be invalid.

// 	/// Initialize the iterator to be invalid.

// 	///

// 	EdgeIt(Invalid) { }

// 	/// This constructor sets the iterator to first edge.

// 	/// This constructor set the iterator to the first edge of

// 	/// node

// 	///@param g the graph

// 	EdgeIt(const StaticGraph& g) { }

// 	/// Edge -> EdgeIt conversion

// 	/// Sets the iterator to the value of the trivial iterator \c e.

// 	/// This feature necessitates that each time we 

// 	/// iterate the edge-set, the iteration order is the same.

// 	EdgeIt(const StaticGraph&, const Edge&) { } 

//     	///Next edge

// 	/// Assign the iterator to the next 

// 	/// edge of the corresponding node.

// 	EdgeIt& operator++() { return *this; }

//       };

//       ///Gives back the target node of an edge.

//       ///Gives back the target node of an edge.

//       ///

//       Node target(Edge) const { return INVALID; }

//       ///Gives back the source node of an edge.

//       ///Gives back the source node of an edge.

//       ///

//       Node source(Edge) const { return INVALID; }

//       /// Read write map of the nodes to type \c T.

//       /// \ingroup concept

//       /// ReadWrite map of the nodes to type \c T.

//       /// \sa Reference

//       /// \warning Making maps that can handle bool type (NodeMap<bool>)

//       /// needs some extra attention!

//       template<class T> 

//       class NodeMap : public ReadWriteMap< Node, T >

//       {

//       public:

// 	///\e

// 	NodeMap(const StaticGraph&) { }

// 	///\e

// 	NodeMap(const StaticGraph&, T) { }

// 	///Copy constructor

// 	NodeMap(const NodeMap&) { }

// 	///Assignment operator

// 	NodeMap& operator=(const NodeMap&) { return *this; }

// 	// \todo fix this concept

//       };

//       /// Read write map of the edges to type \c T.

//       /// \ingroup concept

//       ///Reference map of the edges to type \c T.

//       /// \sa Reference

//       /// \warning Making maps that can handle bool type (EdgeMap<bool>)

//       /// needs some extra attention!

//       template<class T> 

//       class EdgeMap : public ReadWriteMap<Edge,T>

//       {

//       public:

// 	///\e

// 	EdgeMap(const StaticGraph&) { }

// 	///\e

// 	EdgeMap(const StaticGraph&, T) { }

// 	///Copy constructor

// 	EdgeMap(const EdgeMap&) { }

// 	///Assignment operator

// 	EdgeMap& operator=(const EdgeMap&) { return *this; }

// 	// \todo fix this concept    

//       };

//     };

//     /// An empty non-static graph class.

//     /// This class provides everything that \ref StaticGraph

//     /// with additional functionality which enables to build a

//     /// graph from scratch.

//     class ExtendableGraph : public StaticGraph

//     {

//     public:

//       /// Defalult constructor.

//       /// Defalult constructor.

//       ///

//       ExtendableGraph() { }

//       ///Add a new node to the graph.

//       /// \return the new node.

//       ///

//       Node addNode() { return INVALID; }

//       ///Add a new edge to the graph.

//       ///Add a new edge to the graph with source node \c s

//       ///and target node \c t.

//       ///\return the new edge.

//       Edge addEdge(Node s, Node t) { return INVALID; }

//       /// Resets the graph.

//       /// This function deletes all edges and nodes of the graph.

//       /// It also frees the memory allocated to store them.

//       /// \todo It might belong to \ref ErasableGraph.

//       void clear() { }

//     };

//     /// An empty erasable graph class.

//     /// This class is an extension of \ref ExtendableGraph. It also makes it

//     /// possible to erase edges or nodes.

//     class ErasableGraph : public ExtendableGraph

//     {

//     public:

//       /// Defalult constructor.

//       /// Defalult constructor.

//       ///

//       ErasableGraph() { }

//       /// Deletes a node.

//       /// Deletes node \c n node.

//       ///

//       void erase(Node n) { }

//       /// Deletes an edge.

//       /// Deletes edge \c e edge.

//       ///

//       void erase(Edge e) { }

//     };

    /************* New GraphBase stuff **************/

    /// A minimal GraphBase concept

    /// This class describes a minimal concept which can be extended to a

    /// full-featured graph with \ref GraphFactory.

    class GraphBase {

    public:

      GraphBase() {}

      /// \bug Should we demand that Node and Edge be subclasses of the

      /// Graph class???

      typedef GraphItem<'n'> Node;

      typedef GraphItem<'e'> Edge;

//       class Node : public BaseGraphItem<'n'> {};

//       class Edge : public BaseGraphItem<'e'> {};

      // Graph operation

      void firstNode(Node &n) const { }

      void firstEdge(Edge &e) const { }

      void firstOutEdge(Edge &e, Node) const { }

      void firstInEdge(Edge &e, Node) const { }

      void nextNode(Node &n) const { }

      void nextEdge(Edge &e) const { }

      // Question: isn't it reasonable if this methods have a Node

      // parameter? Like this:

      // Edge& nextOut(Edge &e, Node) const { return e; }

      void nextOutEdge(Edge &e) const { }

      void nextInEdge(Edge &e) const { }

      Node target(Edge) const { return Node(); }

      Node source(Edge) const { return Node(); }

      // Do we need id, nodeNum, edgeNum and co. in this basic graphbase

      // concept?

      // Maps.

      //

      // We need a special slimer concept which does not provide maps (it

      // wouldn't be strictly slimer, cause for map-factory id() & friends

      // a required...)

      template<typename T>

      class NodeMap : public GraphMap<GraphBase, Node, T> {};

      template<typename T>

      class EdgeMap : public GraphMap<GraphBase, Node, T> {};

    };

    /**************** The full-featured graph concepts ****************/

    class StaticGraph 

      :  virtual public BaseGraphComponent,

	 public IterableGraphComponent, public MappableGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      template <typename _Graph>

      struct Constraints {

	void constraints() {

	  checkConcept<IterableGraphComponent, _Graph>();

	  checkConcept<MappableGraphComponent, _Graph>();

	}

      };

    };

    class ExtendableGraph 

      :  virtual public BaseGraphComponent, public StaticGraph,

	 public ExtendableGraphComponent, public ClearableGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      template <typename _Graph>

      struct Constraints {

	void constraints() {

	  checkConcept<StaticGraph, _Graph >();

	  checkConcept<ExtendableGraphComponent, _Graph >();

	  checkConcept<ClearableGraphComponent, _Graph >();

	}

      };

    };

    class ErasableGraph 

      :  virtual public BaseGraphComponent, public ExtendableGraph,

	 public ErasableGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      template <typename _Graph>

      struct Constraints {

	void constraints() {

	  checkConcept<ExtendableGraph, _Graph >();

	  checkConcept<ErasableGraphComponent, _Graph >();

	}

      };

    };

    // @}

  } //namespace concept  

} //namespace lemon

#endif // LEMON_CONCEPT_GRAPH_H