/* -*- 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_iterator.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 IdMap The IdMap 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 {

  public:

    /// The graph type of the map. 

    typedef _Graph Graph;

    /// The key type of the map.

    typedef _Item Key;

    /// The id map type of the map.

    typedef AlterationNotifier<_Item> Registry;

    /// The value type of the map.

    typedef _Value Value;

    /// The map type.

    typedef VectorMap Map;

    /// The base class of the map.

    typedef typename Registry::ObserverBase Parent;

  private:

    /// The container type of the map.

    typedef std::vector<Value> Container;	

  public:

    /// 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;

    typedef True FullTypeTag;

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

    /// It construates 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();

    }

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

    /// It construates 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);

    }

    VectorMap(const VectorMap& _copy) 

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

      if (_copy.attached()) {

	attach(*_copy.getRegistry());

	container = _copy.container;

      }

    }

    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:

    /// 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)];

    } 

    /// 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)];

    }

    /// 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.

    void add(const Key& key) {

      int id = graph->id(key);

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

	container.resize(id + 1);

      }

    }

    /// Erases 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.     

    void erase(const Key&) {}

    /// Buildes the map.

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

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

    void build() { 

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

    }

    /// 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.     

    void clear() { 

      container.clear();

    }

  private:

    Container container;

    const Graph *graph;

  };

}

#endif