/* -*- C++ -*-

 * src/lemon/skeletons/graph_component.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.

 *

 */

///\ingroup skeletons

///\file

///\brief The graph components.

#ifndef LEMON_SKELETON_GRAPH_COMPONENT_H

#define LEMON_SKELETON_GRAPH_COMPONENT_H

#include <lemon/invalid.h>

#include <lemon/skeletons/maps.h>

namespace lemon {

  namespace skeleton {

    /// An empty base graph class.

    /// This class provides the most minimal features of a graph structure.

    /// All the graph concepts have to be conform to this base graph.

    class BaseGraphComponent {

    public:

      typedef BaseGraphComponent Graph;

      /// Node class of the graph.

      /// This class represents the Nodes of the graph. 

      ///

      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) {}

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

	/// Equality operator.

	/// Two iterators are equal if and only if they represents the

	/// same node in the graph or both are invalid.

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

	/// Inequality operator.

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

	///

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

 	/// Comparison operator.

	/// This is a strict ordering between the nodes.

	///

	/// This ordering can be different from the iterating order of nodes.

	/// \todo Possibly we don't need it.

	bool operator<(const Node&) { return true;}

      };

      /// Edge class of the graph.

      /// This class represents the Edges of the graph. 

      ///

      class Edge {

      public:

	/// Default constructor.

	/// @warning The default constructor sets the iterator

	/// to an undefined value.

	Edge() {}

	/// Copy constructor.

	/// Copy constructor.

	///

	Edge(const Edge&) {}

	/// Invalid constructor \& conversion.

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

	/// \sa Invalid for more details.

	Edge(Invalid) {}

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

	/// Equality operator.

	/// Two iterators are equal if and only if they represents the

	/// same edge in the graph or both are invalid.

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

	/// Inequality operator.

	/// \sa operator==(const Edge& n)

	///

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

 	/// Comparison operator.

	/// This is a strict ordering between the edges.

	///

	/// This ordering can be different from the iterating order of edges.

	/// \todo Possibly we don't need it.

	bool operator<(const Edge&) { return true;}

      };

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

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

      ///

      Node head(const Edge&) const { return INVALID;}

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

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

      ///

      Node tail(const Edge&) const { return INVALID;}

    };

    /// Concept check structure for BaseGraph.

    /// Concept check structure for BaseGraph.

    ///

    template <typename Graph>

    struct BaseGraphComponentConcept {

      typedef typename Graph::Node Node;

      typedef typename Graph::Edge Edge;

      void constraints() {

	{

	  Node ni; 

	  Node nj(ni); 

	  Node nk(INVALID);

	  ni = nj;

	  bool b; b = true;

	  b = (ni == INVALID); b = (ni != INVALID);

	  b = (ni==nj); b = (ni != nj); b=( ni < nj);

	}

	{

	  Edge ei; 

	  Edge ej(ei); 

	  Edge ek(INVALID);

	  ei = ej;

	  bool b; b = true;

	  b = (ei == INVALID); b = (ei != INVALID);

	  b = (ei==ej); b = (ei != ej); b=( ei < ej);

	}

	{

	  const Graph& const_graph = graph;

	  Node n;

	  Edge e;

	  n = const_graph.tail(e);

	  n = const_graph.head(e);

	}      

      }

      Graph& graph;

    };

    /// An empty iterable base graph class.

    /// This class provides beside the core graph features

    /// core iterable interface for the graph structure.

    /// Most of the base graphs should be conform to this concept.

    class BaseIterableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      /// Gives back the first Node in the iterating order.

      /// Gives back the first Node in the iterating order.

      ///     

      void first(Node&) const {}

      /// Gives back the next Node in the iterating order.

      /// Gives back the next Node in the iterating order.

      ///     

      void next(Node&) const {}

      /// Gives back the first Edge in the iterating order.

      /// Gives back the first Edge in the iterating order.

      ///     

      void first(Edge&) const {}

      /// Gives back the next Edge in the iterating order.

      /// Gives back the next Edge in the iterating order.

      ///     

      void next(Edge&) const {}

      /// Gives back the first of the Edges point to the given Node.

      /// Gives back the first of the Edges point to the given Node.

      ///     

      void firstIn(Edge&, const Node&) const {}

      /// Gives back the next of the Edges points to the given Node.

      /// Gives back the next of the Edges points to the given Node.

      ///

      void nextIn(Edge&) const {}

      /// Gives back the first of the Edges start from the given Node.

      /// Gives back the first of the Edges start from the given Node.

      ///     

      void firstOut(Edge&, const Node&) const {}

      /// Gives back the next of the Edges start from the given Node.

      /// Gives back the next of the Edges start from the given Node.

      ///     

      void nextOut(Edge&) const {}

    };

    /// Concept check structure for IterableBaseGraph.

    /// Concept check structure for IterableBaseGraph.

    ///

    template <typename Graph>

    struct BaseIterableGraphComponentConcept {

      void constraints() { 

	const Graph& const_graph = graph;

	typename Graph::Node node;      

	typename Graph::Edge edge;

	{

	  const_graph.first(node);

	  const_graph.next(node);

	}

	{

	  const_graph.first(edge);

	  const_graph.next(edge);

	}

	{

	  const_graph.firstIn(edge, node);

	  const_graph.nextIn(edge);

	}

	{

	  const_graph.firstOut(edge, node);

	  const_graph.nextOut(edge);

	}

      }

      Graph& graph;

    };

    /// An empty idable base graph class.

    /// This class provides beside the core graph features

    /// core id functions for the graph structure.

    /// The most of the base graphs should be conform to this concept.

    /// The id's are unique and immutable.

    class IDableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      /// Gives back an unique integer id for the Node. 

      /// Gives back an unique integer id for the Node. 

      ///

      int id(const Node&) const { return -1;}

      /// Gives back an unique integer id for the Edge. 

      /// Gives back an unique integer id for the Edge. 

      ///

      int id(const Edge&) const { return -1;}

    };

    /// Concept check structure for IdableBaseGraph.

    /// Concept check structure for IdableBaseGraph.

    ///

    template <typename Graph>

    struct IDableGraphComponentConcept {

      void constraints() {

	const Graph& const_graph = graph;

	typename Graph::Node node;

	int nid = const_graph.id(node);

	nid = const_graph.id(node);

	typename Graph::Edge edge;

	int eid = const_graph.id(edge);

	eid = const_graph.id(edge);

      }

      Graph& graph;

    };

    /// An empty max-idable base graph class.

    /// This class provides beside the core graph features

    /// core max id functions for the graph structure.

    /// The most of the base graphs should be conform to this concept.

    /// The id's are unique and immutable.

    class MaxIDableGraphComponent : virtual public BaseGraphComponent {

    public:

      /// Gives back an integer greater or equal to the maximum Node id. 

      /// Gives back an integer greater or equal to the maximum Node id. 

      ///

      int maxEdgeId() const { return -1;}

      /// Gives back an integer greater or equal to the maximum Edge id. 

      /// Gives back an integer greater or equal to the maximum Edge id. 

      ///

      int maxNodeId() const { return -1;}

    };

    /// Concept check structure for MaxIdableBaseGraph.

    /// Concept check structure for MaxIdableBaseGraph.

    ///

    template <typename Graph>

    struct MaxIDableGraphComponentConcept {

      void constraints() {

	const Graph& const_graph = graph;

	int nid = const_graph.maxEdgeId();

	ignore_unused_variable_warning(nid);

	int eid = const_graph.maxNodeId();

	ignore_unused_variable_warning(eid);

      }

      Graph& graph;

    };

    /// An empty extendable base graph class.

    /// This class provides beside the core graph features

    /// core graph extend interface for the graph structure.

    /// The most of the base graphs should be conform to this concept.

    class BaseExtendableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      /// Adds a new Node to the graph.

      /// Adds a new Node to the graph.

      ///

      Node addNode() {

	return INVALID;

      }

      /// Adds a new Edge connects the two Nodes to the graph.

      /// Adds a new Edge connects the two Nodes to the graph.

      ///

      Edge addEdge(const Node& from, const Node& to) {

	return INVALID;

      }

    };

    /// Concept check structure for ExtendableBaseGraph.

    /// Concept check structure for ExtendableBaseGraph.

    ///

    template <typename Graph>

    struct BaseExtendableGraphComponentConcept {

      void constraints() {

	typename Graph::Node node_a, node_b;

	node_a = graph.addNode();

	typename Graph::Edge edge;

	edge = graph.addEdge(node_a, node_b);

      }

      Graph& graph;

    };

    /// An empty erasable base graph class.

    /// This class provides beside the core graph features

    /// core erase functions for the graph structure.

    /// The most of the base graphs should be conform to this concept.

    class BaseErasableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      /// Erase a Node from the graph.

      /// Erase a Node from the graph. This function should not

      /// erase edges connecting to the Node.

      void erase(const Node&) {}    

      /// Erase an Edge from the graph.

      /// Erase an Edge from the graph.

      ///

      void erase(const Edge&) {}

    };

    /// Concept check structure for ErasableBaseGraph.

    /// Concept check structure for ErasableBaseGraph.

    ///

    template <typename Graph>

    struct BaseErasableGraphComponentConcept {

      void constraints() {

	typename Graph::Node node;

	graph.erase(node);

	typename Graph::Edge edge;

	graph.erase(edge);

      }

      Graph& graph;

    };

    /// An empty clearable base graph class.

    /// This class provides beside the core graph features

    /// core clear functions for the graph structure.

    /// The most of the base graphs should be conform to this concept.

    class BaseClearableGraphComponent : virtual public BaseGraphComponent {

    public:

      /// Erase all the Nodes and Edges from the graph.

      /// Erase all the Nodes and Edges from the graph.

      ///

      void clear() {}    

    };

    /// Concept check function for ErasableBaseGraph.

    /// Concept check function for ErasableBaseGraph.

    ///

    template <typename Graph>

    struct BaseClearableGraphComponentConcept {

      void constraints() {

	graph.clear();

      }

      Graph& graph;

    };

    class IterableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef IterableGraphComponent Graph;

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      class NodeIt : public Node {

      public:

	NodeIt() {}

	NodeIt(Invalid) {}

	NodeIt(const Graph&) {}

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

	//	Node operator*() const { return INVALID; }

	bool operator==(const NodeIt&) { return true;}

	bool operator!=(const NodeIt&) { return true;}

      };

      class EdgeIt : public Edge {

      public:

	EdgeIt() {}

	EdgeIt(Invalid) {}

	EdgeIt(const Graph&) {}

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

	//	Edge operator*() const { return INVALID; }

	bool operator==(const EdgeIt&) { return true;}

	bool operator!=(const EdgeIt&) { return true;}

      };

      class InEdgeIt : public Edge {

      public:

	InEdgeIt() {}

	InEdgeIt(Invalid) {}

	InEdgeIt(const Graph&, const Node&) {}

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

	//	Edge operator*() const { return INVALID; }

	bool operator==(const InEdgeIt&) { return true;}

	bool operator!=(const InEdgeIt&) { return true;}

      };

      class OutEdgeIt : public Edge {

      public:

	OutEdgeIt() {}

	OutEdgeIt(Invalid) {}

	OutEdgeIt(const Graph&, const Node&) {}

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

	//	Edge operator*() const { return INVALID; }

	bool operator==(const OutEdgeIt&) { return true;}

	bool operator!=(const OutEdgeIt&) { return true;}

      };

    };

    template <typename Graph> 

    struct IterableGraphComponentConcept {

      void constraints() {

	typedef typename Graph::Node Node;

	typedef typename Graph::NodeIt NodeIt;

	typedef typename Graph::Edge Edge;

	typedef typename Graph::EdgeIt EdgeIt;

	typedef typename Graph::InEdgeIt InEdgeIt;

	typedef typename Graph::OutEdgeIt OutEdgeIt;

	{

	  NodeIt it; 

	  NodeIt jt(it); 

	  NodeIt kt(INVALID); 

	  NodeIt lt(graph);

	  it = jt;

	  jt = ++it;

	  bool b;

	  b = (it == INVALID); 

	  b = (it != INVALID);

	  b = (it == jt); 

	  b = (it != jt);

	  Node node = it;

	  node = it;

	}

	{

	  EdgeIt it; 

	  EdgeIt jt(it); 

	  EdgeIt kt(INVALID); 

	  EdgeIt lt(graph);

	  it = jt;

	  jt = ++it;

	  bool b;

	  b = (it == INVALID); 

	  b = (it != INVALID);

	  b = (it == jt); 

	  b = (it != jt);

	  Edge edge = it;

	  edge = it;

	}

	{

	  InEdgeIt it; 

	  InEdgeIt jt(it); 

	  InEdgeIt kt(INVALID); 

	  Node node;

	  InEdgeIt lt(graph, node);

	  it = jt;

	  jt = ++it;

	  bool b;

	  b = (it == INVALID); 

	  b = (it != INVALID);

	  b = (it == jt); 

	  b = (it != jt);

	  Edge edge = it;

	  edge = it;

	}

	{

	  OutEdgeIt it; 

	  OutEdgeIt jt(it); 

	  OutEdgeIt kt(INVALID); 

	  Node node;

	  OutEdgeIt lt(graph, node);

	  it = jt;

	  jt = ++it;

	  bool b;

	  b = (it == INVALID); 

	  b = (it != INVALID);

	  b = (it == jt); 

	  b = (it != jt);

	  Edge edge = it;

	  edge = it;

	}

      }

      Graph& graph;

    };

    class IdMappableGraphComponent : virtual public BaseGraphComponent {

      typedef IdMappableGraphComponent Graph;

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

    public:

      class NodeIdMap : public ReadMap<Node, int> {

      public:

	NodeIdMap(const Graph&) {}

	int maxId() const { return -1;}

      };

      class EdgeIdMap : public ReadMap<Edge, int> {

      public:

	EdgeIdMap(const Graph&) {}

	int maxId() const { return -1;}

      };

    };

    template <typename Graph>

    struct IdMappableGraphComponentConcept {

      void constraints() {	

	{

	  typedef typename Graph::EdgeIdMap EdgeIdMap;

	  function_requires<ReadMapConcept<EdgeIdMap> >();

	  EdgeIdMap edge_map(graph);

	  int n = edge_map.maxId();

	  ignore_unused_variable_warning(n);

	}

	{

	  typedef typename Graph::NodeIdMap NodeIdMap;

	  function_requires<ReadMapConcept<NodeIdMap> >();

	  NodeIdMap node_map(graph);

	  int n = node_map.maxId();

	  ignore_unused_variable_warning(n);

	}

      }

      Graph& graph;

    };

    class MappableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef MappableGraphComponent Graph;

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      template <typename Value>

      class NodeMap : public ReferenceMap<Node, Value> {

      public:

	NodeMap(const Graph&) {}

	NodeMap(const Graph&, const Value&) {}

	NodeMap(const NodeMap&) {}

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

      };

      template <typename Value>

      class EdgeMap : public ReferenceMap<Edge, Value> {

      public:

	EdgeMap(const Graph&) {}

	EdgeMap(const Graph&, const Value&) {}

	EdgeMap(const EdgeMap&) {}

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

      };

    };

    template <typename Graph>

    struct MappableGraphComponentConcept {

      struct Type {

	int value;

	Type() : value(0) {}

	Type(int _v) : value(_v) {}

      };

      void constraints() {

	{ // int map test

	  typedef typename Graph::template NodeMap<int> IntNodeMap;

	  function_requires<GraphMapConcept<IntNodeMap,Graph> >();

	} { // bool map test

	  typedef typename Graph::template NodeMap<bool> BoolNodeMap;

	  function_requires<GraphMapConcept<BoolNodeMap,Graph> >();

	} { // Type map test

	  typedef typename Graph::template NodeMap<Type> TypeNodeMap;

	  function_requires<GraphMapConcept<TypeNodeMap,Graph> >();

	} 

	{ // int map test

	  typedef typename Graph::template EdgeMap<int> IntEdgeMap;

	  function_requires<GraphMapConcept<IntEdgeMap,Graph> >();

	} { // bool map test

	  typedef typename Graph::template EdgeMap<bool> BoolEdgeMap;

	  function_requires<GraphMapConcept<BoolEdgeMap,Graph> >();

	} { // Type map test

	  typedef typename Graph::template EdgeMap<Type> TypeEdgeMap;

	  function_requires<GraphMapConcept<TypeEdgeMap,Graph> >();

	} 

      }

      Graph& graph;

    };

    class ExtendableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef ExtendableGraphComponent Graph;

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      Node addNode() {

	return INVALID;

      }

      Edge addEdge(const Node& from, const Node& to) {

	return INVALID;

      }

    };

    template <typename Graph>

    struct ExtendableGraphComponentConcept {

      void constraints() {

	typename Graph::Node node_a, node_b;

	node_a = graph.addNode();

	typename Graph::Edge edge;

	edge = graph.addEdge(node_a, node_b);      

      }

      Graph& graph;

    };

    class ErasableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef ErasableGraphComponent Graph;

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      void erase(const Node&) {}    

      void erase(const Edge&) {}

    };

    template <typename Graph>

    struct ErasableGraphComponentConcept {

      void constraints() {

	typename Graph::Node node;

	graph.erase(node);

	typename Graph::Edge edge;

	graph.erase(edge);      

      }

      Graph& graph;

    };

    class ClearableGraphComponent : virtual public BaseGraphComponent {

    public:

      typedef ClearableGraphComponent Graph;

      typedef BaseGraphComponent::Node Node;

      typedef BaseGraphComponent::Edge Edge;

      void clear() {}    

    };

    template <typename Graph>

    struct ClearableGraphComponentConcept {

      void constraints() {

	graph.clear();

      }

      Graph& graph;

    };

  }

}

#endif