/* -*- C++ -*-

 * lemon/full_graph.h - Part of LEMON, a generic C++ optimization library

 *

 * Copyright (C) 2006 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport

 * (Egervary Research Group on Combinatorial Optimization, 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_FULL_GRAPH_H

#define LEMON_FULL_GRAPH_H

#include <cmath>

#include <lemon/bits/iterable_graph_extender.h>

#include <lemon/bits/alteration_notifier.h>

#include <lemon/bits/static_map.h>

#include <lemon/bits/graph_extender.h>

#include <lemon/invalid.h>

#include <lemon/utility.h>

///\ingroup graphs

///\file

///\brief FullGraph and FullUGraph classes.

namespace lemon {

  class FullGraphBase {

    int _nodeNum;

    int _edgeNum;

  public:

    typedef FullGraphBase Graph;

    class Node;

    class Edge;

  public:

    FullGraphBase() {}

    ///Creates a full graph with \c n nodes.

    void construct(int n) { _nodeNum = n; _edgeNum = n * n; }

    ///

    //    FullGraphBase(const FullGraphBase &_g)

    //      : _nodeNum(_g.nodeNum()), _edgeNum(_nodeNum*_nodeNum) { }

    typedef True NodeNumTag;

    typedef True EdgeNumTag;

    ///Number of nodes.

    int nodeNum() const { return _nodeNum; }

    ///Number of edges.

    int edgeNum() const { return _edgeNum; }

    /// Maximum node ID.

    /// Maximum node ID.

    ///\sa id(Node)

    int maxNodeId() const { return _nodeNum-1; }

    /// Maximum edge ID.

    /// Maximum edge ID.

    ///\sa id(Edge)

    int maxEdgeId() const { return _edgeNum-1; }

    Node source(Edge e) const { return e.id % _nodeNum; }

    Node target(Edge e) const { return e.id / _nodeNum; }

    /// Node ID.

    /// The ID of a valid Node is a nonnegative integer not greater than

    /// \ref maxNodeId(). The range of the ID's is not surely continuous

    /// and the greatest node ID can be actually less then \ref maxNodeId().

    ///

    /// The ID of the \ref INVALID node is -1.

    ///\return The ID of the node \c v. 

    static int id(Node v) { return v.id; }

    /// Edge ID.

    /// The ID of a valid Edge is a nonnegative integer not greater than

    /// \ref maxEdgeId(). The range of the ID's is not surely continuous

    /// and the greatest edge ID can be actually less then \ref maxEdgeId().

    ///

    /// The ID of the \ref INVALID edge is -1.

    ///\return The ID of the edge \c e. 

    static int id(Edge e) { return e.id; }

    static Node nodeFromId(int id) { return Node(id);}

    static Edge edgeFromId(int id) { return Edge(id);}

    typedef True FindEdgeTag;

    /// Finds an edge between two nodes.

    /// Finds an edge from node \c u to node \c v.

    ///

    /// If \c prev is \ref INVALID (this is the default value), then

    /// It finds the first edge from \c u to \c v. Otherwise it looks for

    /// the next edge from \c u to \c v after \c prev.

    /// \return The found edge or INVALID if there is no such an edge.

    Edge findEdge(Node u,Node v, Edge prev = INVALID) const {

      return prev.id == -1 ? Edge(*this, u.id, v.id) : INVALID;

    }

    class Node {

      friend class FullGraphBase;

    protected:

      int id;

      Node(int _id) : id(_id) {}

    public:

      Node() {}

      Node (Invalid) : id(-1) {}

      bool operator==(const Node node) const {return id == node.id;}

      bool operator!=(const Node node) const {return id != node.id;}

      bool operator<(const Node node) const {return id < node.id;}

    };

    class Edge {

      friend class FullGraphBase;

    protected:

      int id;  // _nodeNum * target + source;

      Edge(int _id) : id(_id) {}

      Edge(const FullGraphBase& _graph, int source, int target) 

	: id(_graph._nodeNum * target+source) {}

    public:

      Edge() { }

      Edge (Invalid) { id = -1; }

      bool operator==(const Edge edge) const {return id == edge.id;}

      bool operator!=(const Edge edge) const {return id != edge.id;}

      bool operator<(const Edge edge) const {return id < edge.id;}

    };

    void first(Node& node) const {

      node.id = _nodeNum-1;

    }

    static void next(Node& node) {

      --node.id;

    }

    void first(Edge& edge) const {

      edge.id = _edgeNum-1;

    }

    static void next(Edge& edge) {

      --edge.id;

    }

    void firstOut(Edge& edge, const Node& node) const {

      edge.id = _edgeNum + node.id - _nodeNum;

    }

    void nextOut(Edge& edge) const {

      edge.id -= _nodeNum;

      if (edge.id < 0) edge.id = -1;

    }

    void firstIn(Edge& edge, const Node& node) const {

      edge.id = node.id * _nodeNum;

    }

    void nextIn(Edge& edge) const {

      ++edge.id;

      if (edge.id % _nodeNum == 0) edge.id = -1;

    }

  };

  typedef StaticMappableGraphExtender<

    IterableGraphExtender<

    AlterableGraphExtender<

    GraphExtender<FullGraphBase> > > > ExtendedFullGraphBase;

  /// \ingroup graphs

  ///

  /// \brief A full graph class.

  ///

  /// This is a simple and fast directed full graph implementation.

  /// It is completely static, so you can neither add nor delete either

  /// edges or nodes.

  /// Thus it conforms to

  /// the \ref concept::StaticGraph "StaticGraph" concept

  /// \sa concept::StaticGraph.

  ///

  /// \author Alpar Juttner

  class FullGraph : public ExtendedFullGraphBase {

  public:

    FullGraph(int n) { construct(n); }

  };

  class FullUGraphBase {

    int _nodeNum;

    int _edgeNum;

  public:

    typedef FullUGraphBase Graph;

    class Node;

    class Edge;

  public:

    FullUGraphBase() {}

    ///Creates a full graph with \c n nodes.

    void construct(int n) { _nodeNum = n; _edgeNum = n * (n - 1) / 2; }

    ///

    //    FullGraphBase(const FullGraphBase &_g)

    //      : _nodeNum(_g.nodeNum()), _edgeNum(_nodeNum*_nodeNum) { }

    typedef True NodeNumTag;

    typedef True EdgeNumTag;

    ///Number of nodes.

    int nodeNum() const { return _nodeNum; }

    ///Number of edges.

    int edgeNum() const { return _edgeNum; }

    /// Maximum node ID.

    /// Maximum node ID.

    ///\sa id(Node)

    int maxNodeId() const { return _nodeNum-1; }

    /// Maximum edge ID.

    /// Maximum edge ID.

    ///\sa id(Edge)

    int maxEdgeId() const { return _edgeNum-1; }

    Node source(Edge e) const { 

      /// \todo we may do it faster

      return Node(((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2);

    }

    Node target(Edge e) const { 

      int source = ((int)sqrt((double)(1 + 8 * e.id)) + 1) / 2;;

      return Node(e.id - (source) * (source - 1) / 2);

    }

    /// Node ID.

    /// The ID of a valid Node is a nonnegative integer not greater than

    /// \ref maxNodeId(). The range of the ID's is not surely continuous

    /// and the greatest node ID can be actually less then \ref maxNodeId().

    ///

    /// The ID of the \ref INVALID node is -1.

    ///\return The ID of the node \c v. 

    static int id(Node v) { return v.id; }

    /// Edge ID.

    /// The ID of a valid Edge is a nonnegative integer not greater than

    /// \ref maxEdgeId(). The range of the ID's is not surely continuous

    /// and the greatest edge ID can be actually less then \ref maxEdgeId().

    ///

    /// The ID of the \ref INVALID edge is -1.

    ///\return The ID of the edge \c e. 

    static int id(Edge e) { return e.id; }

    /// Finds an edge between two nodes.

    /// Finds an edge from node \c u to node \c v.

    ///

    /// If \c prev is \ref INVALID (this is the default value), then

    /// It finds the first edge from \c u to \c v. Otherwise it looks for

    /// the next edge from \c u to \c v after \c prev.

    /// \return The found edge or INVALID if there is no such an edge.

    Edge findEdge(Node u, Node v, Edge prev = INVALID) const {

      if (prev.id != -1 || u.id <= v.id) return -1;

      return Edge(u.id * (u.id - 1) / 2 + v.id);

    }

    typedef True FindEdgeTag;

    class Node {

      friend class FullUGraphBase;

    protected:

      int id;

      Node(int _id) { id = _id;}

    public:

      Node() {}

      Node (Invalid) { id = -1; }

      bool operator==(const Node node) const {return id == node.id;}

      bool operator!=(const Node node) const {return id != node.id;}

      bool operator<(const Node node) const {return id < node.id;}

    };

    class Edge {

      friend class FullUGraphBase;

    protected:

      int id;  // _nodeNum * target + source;

      Edge(int _id) : id(_id) {}

    public:

      Edge() { }

      Edge (Invalid) { id = -1; }

      bool operator==(const Edge edge) const {return id == edge.id;}

      bool operator!=(const Edge edge) const {return id != edge.id;}

      bool operator<(const Edge edge) const {return id < edge.id;}

    };

    void first(Node& node) const {

      node.id = _nodeNum - 1;

    }

    static void next(Node& node) {

      --node.id;

    }

    void first(Edge& edge) const {

      edge.id = _edgeNum - 1;

    }

    static void next(Edge& edge) {

      --edge.id;

    }

    void firstOut(Edge& edge, const Node& node) const {      

      int src = node.id;

      int trg = 0;

      edge.id = (trg < src ? src * (src - 1) / 2 + trg : -1);

    }

    /// \todo with specialized iterators we can make faster iterating

    void nextOut(Edge& edge) const {

      int src = source(edge).id;

      int trg = target(edge).id;

      ++trg;

      edge.id = (trg < src ? src * (src - 1) / 2 + trg : -1);

    }

    void firstIn(Edge& edge, const Node& node) const {

      int src = node.id + 1;

      int trg = node.id;

      edge.id = (src < _nodeNum ? src * (src - 1) / 2 + trg : -1);

    }

    void nextIn(Edge& edge) const {

      int src = source(edge).id;

      int trg = target(edge).id;

      ++src;

      edge.id = (src < _nodeNum ? src * (src - 1) / 2 + trg : -1);

    }

  };

  typedef StaticMappableUGraphExtender<

    IterableUGraphExtender<

    AlterableUGraphExtender<

    UGraphExtender<FullUGraphBase> > > > ExtendedFullUGraphBase;

  /// \ingroup graphs

  ///

  /// \brief An undirected full graph class.

  ///

  /// This is a simple and fast undirected full graph implementation.

  /// It is completely static, so you can neither add nor delete either

  /// edges or nodes.

  ///

  /// The main difference beetween the \e FullGraph and \e FullUGraph class

  /// is that this class conforms to the undirected graph concept and

  /// it does not contain the loop edges.

  ///

  /// \sa FullGraph

  ///

  /// \author Balazs Dezso

  class FullUGraph : public ExtendedFullUGraphBase {

  public:

    FullUGraph(int n) { construct(n); }

  };

  class FullBpUGraphBase {

  protected:

    int _aNodeNum;

    int _bNodeNum;

    int _edgeNum;

  public:

    class NodeSetError : public LogicError {

      virtual const char* exceptionName() const { 

	return "lemon::FullBpUGraph::NodeSetError";

      }

    };

    class Node {

      friend class FullBpUGraphBase;

    protected:

      int id;

      Node(int _id) : id(_id) {}

    public:

      Node() {}

      Node(Invalid) { id = -1; }

      bool operator==(const Node i) const {return id==i.id;}

      bool operator!=(const Node i) const {return id!=i.id;}

      bool operator<(const Node i) const {return id<i.id;}

    };

    class Edge {

      friend class FullBpUGraphBase;

    protected:

      int id;

      Edge(int _id) { id = _id;}

    public:

      Edge() {}

      Edge (Invalid) { id = -1; }

      bool operator==(const Edge i) const {return id==i.id;}

      bool operator!=(const Edge i) const {return id!=i.id;}

      bool operator<(const Edge i) const {return id<i.id;}

    };

    void construct(int aNodeNum, int bNodeNum) {

      _aNodeNum = aNodeNum;

      _bNodeNum = bNodeNum;

      _edgeNum = aNodeNum * bNodeNum;

    }

    void firstANode(Node& node) const {

      node.id = 2 * _aNodeNum - 2;

      if (node.id < 0) node.id = -1; 

    }

    void nextANode(Node& node) const {

      node.id -= 2;

      if (node.id < 0) node.id = -1; 

    }

    void firstBNode(Node& node) const {

      node.id = 2 * _bNodeNum - 1;

    }

    void nextBNode(Node& node) const {

      node.id -= 2;

    }

    void first(Node& node) const {

      if (_aNodeNum > 0) {

	node.id = 2 * _aNodeNum - 2;

      } else {

	node.id = 2 * _bNodeNum - 1;

      }

    }

    void next(Node& node) const {

      node.id -= 2;

      if (node.id == -2) {

	node.id = 2 * _bNodeNum - 1;

      }

    }

    void first(Edge& edge) const {

      edge.id = _edgeNum - 1;

    }

    void next(Edge& edge) const {

      --edge.id;

    }

    void firstOut(Edge& edge, const Node& node) const {

      LEMON_ASSERT((node.id & 1) == 0, NodeSetError());

      edge.id = (node.id >> 1) * _bNodeNum;

    }

    void nextOut(Edge& edge) const {

      ++(edge.id);

      if (edge.id % _bNodeNum == 0) edge.id = -1;

    }

    void firstIn(Edge& edge, const Node& node) const {

      LEMON_ASSERT((node.id & 1) == 1, NodeSetError());

      edge.id = (node.id >> 1);

    }

    void nextIn(Edge& edge) const {

      edge.id += _bNodeNum;

      if (edge.id >= _edgeNum) edge.id = -1;

    }

    static int id(const Node& node) {

      return node.id;

    }

    static Node nodeFromId(int id) {

      return Node(id);

    }

    int maxNodeId() const {

      return _aNodeNum > _bNodeNum ? 

	_aNodeNum * 2 - 2 : _bNodeNum * 2 - 1;

    }

    static int id(const Edge& edge) {

      return edge.id;

    }

    static Edge edgeFromId(int id) {

      return Edge(id);

    }

    int maxEdgeId() const {

      return _edgeNum - 1;

    }

    static int aNodeId(const Node& node) {

      return node.id >> 1;

    }

    static Node fromANodeId(int id, Node) {

      return Node(id << 1);

    }

    int maxANodeId() const {

      return _aNodeNum;

    }

    static int bNodeId(const Node& node) {

      return node.id >> 1;

    }

    static Node fromBNodeId(int id) {

      return Node((id << 1) + 1);

    }

    int maxBNodeId() const {

      return _bNodeNum;

    }

    Node aNode(const Edge& edge) const {

      return Node((edge.id / _bNodeNum) << 1);

    }

    Node bNode(const Edge& edge) const {

      return Node(((edge.id % _bNodeNum) << 1) + 1);

    }

    static bool aNode(const Node& node) {

      return (node.id & 1) == 0;

    }

    static bool bNode(const Node& node) {

      return (node.id & 1) == 1;

    }

    static Node aNode(int index) {

      return Node(index << 1);

    }

    static Node bNode(int index) {

      return Node((index << 1) + 1);

    }

  };

  typedef StaticMappableBpUGraphExtender<

    IterableBpUGraphExtender<

    AlterableBpUGraphExtender<

    BpUGraphExtender <

    FullBpUGraphBase> > > >

  ExtendedFullBpUGraphBase;

  /// \ingroup graphs

  ///

  /// \brief An undirected full bipartite graph class.

  ///

  /// This is a simple and fast bipartite undirected full graph implementation.

  /// It is completely static, so you can neither add nor delete either

  /// edges or nodes.

  ///

  /// \sa FullGraph

  ///

  /// \author Balazs Dezso

  class FullBpUGraph : 

    public ExtendedFullBpUGraphBase {

  public:

    typedef ExtendedFullBpUGraphBase Parent;

    FullBpUGraph(int aNodeNum, int bNodeNum) {

      Parent::construct(aNodeNum, bNodeNum);

    }

  };

} //namespace lemon

#endif //LEMON_FULL_GRAPH_H