/* -*- C++ -*-

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

  *

  * Copyright (C) 2005 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_VECTOR_MAP_H

 #define LEMON_VECTOR_MAP_H

 #include <vector>

 #include <algorithm>

 #include <lemon/utility.h>

 #include <lemon/bits/map_extender.h>

 #include <lemon/bits/alteration_notifier.h>

 #include <lemon/concept_check.h>

 #include <lemon/concept/maps.h>

 /// \ingroup graphmapfactory

 ///

 ///\file

 ///\brief Vector based graph maps.

 namespace lemon {

   /// \ingroup graphmapfactory

   ///

   /// \brief Graph map based on the std::vector storage.

   ///

   /// The VectorMap template class is graph map structure what

   /// automatically updates the map when a key is added to or erased from

   /// the map. This map factory uses the allocators to implement 

   /// the container functionality. This map factory

   /// uses the std::vector to implement the container function.

   ///

   /// \param Registry The AlterationNotifier that will notify this map.

   /// \param Item The item type of the graph items.

   /// \param Value The value type of the map.

   /// 

   /// \author Balazs Dezso

   template <

     typename _Graph, 

     typename _Item,    

     typename _Value

     >

   class VectorMap : public AlterationNotifier<_Item>::ObserverBase {

   private:

     /// The container type of the map.

     typedef std::vector<_Value> Container;	

   public:

     /// The graph type of the map. 

     typedef _Graph Graph;

     /// The reference map tag.

     typedef True ReferenceMapTag;

     /// The key type of the map.

     typedef _Item Key;

     /// The value type of the map.

     typedef _Value Value;

     typedef AlterationNotifier<_Item> Registry;

     /// The map type.

     typedef VectorMap Map;

     /// The base class of the map.

     typedef typename Registry::ObserverBase Parent;

     /// The reference type of the map;

     typedef typename Container::reference Reference;

     /// The pointer type of the map;

     typedef typename Container::pointer Pointer;

     /// The const value type of the map.

     typedef const Value ConstValue;

     /// The const reference type of the map;

     typedef typename Container::const_reference ConstReference;

     /// The pointer type of the map;

     typedef typename Container::const_pointer ConstPointer;

     /// \brief Constructor to attach the new map into the registry.

     ///

     /// It constructs a map and attachs it into the registry.

     /// It adds all the items of the graph to the map.

     VectorMap(const Graph& _g) : graph(&_g) {

       attach(_g.getNotifier(_Item()));

       build();

     }

     /// \brief Constructor uses given value to initialize the map. 

     ///

     /// It constructs a map uses a given value to initialize the map. 

     /// It adds all the items of the graph to the map.

     VectorMap(const Graph& _g, const Value& _v) : graph(&_g) { 

       attach(_g.getNotifier(_Item()));

       container.resize(graph->maxId(_Item()) + 1, _v);

     }

     /// \brief Copy constructor

     ///

     /// Copy constructor.

     VectorMap(const VectorMap& _copy) 

       : Parent(), graph(_copy.getGraph()) {

       if (_copy.attached()) {

 	attach(*_copy.getRegistry());

 	container = _copy.container;

       }

     }

     /// \brief Destrcutor

     ///

     /// Destructor.

     virtual ~VectorMap() {

       if (attached()) {

 	detach();

       }

     }

   private:

     VectorMap& operator=(const VectorMap&);

   protected:

     using Parent::attach;

     using Parent::detach;

     using Parent::attached;

     const Graph* getGraph() const {

       return graph;

     }

   public:

     /// \brief The subcript operator.

     ///

     /// The subscript operator. The map can be subscripted by the

     /// actual items of the graph.      

     Reference operator[](const Key& key) {

       return container[graph->id(key)];

     } 

     /// \brief The const subcript operator.

     ///

     /// The const subscript operator. The map can be subscripted by the

     /// actual items of the graph. 

     ConstReference operator[](const Key& key) const {

       return container[graph->id(key)];

     }

     /// \brief The setter function of the map.

     ///

     /// It the same as operator[](key) = value expression.

     void set(const Key& key, const Value& value) {

       (*this)[key] = value;

     }

   protected:

     /// \brief Adds a new key to the map.

     ///		

     /// It adds a new key to the map. It called by the observer registry

     /// and it overrides the add() member function of the observer base.     

     virtual void add(const Key& key) {

       int id = graph->id(key);

       if (id >= (int)container.size()) {

 	container.resize(id + 1);

       }

     }

     /// \brief Erase a key from the map.

     ///

     /// Erase a key from the map. It called by the observer registry

     /// and it overrides the erase() member function of the observer base.     

     virtual void erase(const Key&) {}

     /// \brief Buildes the map.

     ///	

     /// It buildes the map. It called by the observer registry

     /// and it overrides the build() member function of the observer base.

     virtual void build() { 

       container.resize(graph->maxId(_Item()) + 1);

     }

     /// \brief Clear the map.

     ///

     /// It erase all items from the map. It called by the observer registry

     /// and it overrides the clear() member function of the observer base.     

     virtual void clear() { 

       container.clear();

     }

   private:

     Container container;

     const Graph *graph;

   };

 }

 #endif