/* -*- 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.

     /// The 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