/* -*- C++ -*-

 * src/lemon/array_map.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.

 *

 */

#ifndef LEMON_ARRAY_MAP_H

#define LEMON_ARRAY_MAP_H

#include <memory>

#include <lemon/map_iterator.h>

///\ingroup graphmaps

///\file

///\brief Graph maps that construates and destruates

///their elements dynamically.

namespace lemon {

  /// \addtogroup graphmaps

  /// @{

  /** The ArrayMap 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.

   *

   *  The template parameter is the MapRegistry that the maps

   *  will belong to and the ValueType.

   */

  template <typename _Graph, 

	    typename _Item,

	    typename _ItemIt,

	    typename _IdMap,

	    typename _Value>

  class ArrayMap : public AlterationObserverRegistry<_Item>::ObserverBase {

  public:

    /// The graph type of the maps. 

    typedef _Graph Graph;

    /// The key type of the maps.

    typedef _Item KeyType;

    typedef AlterationObserverRegistry<_Item> Registry;

  private:

    /// The iterator to iterate on the keys.

    typedef _ItemIt KeyIt;

    typedef _IdMap IdMap;

    typedef _Value Value;

    /// The MapBase of the Map which imlements the core regisitry function.

    typedef typename Registry::ObserverBase Parent;

  public:

    /// The value type of the map.

    typedef Value ValueType;

    /// The reference type of the map;

    typedef Value& ReferenceType;

    /// The pointer type of the map;

    typedef Value* PointerType;

    /// The const value type of the map.

    typedef const Value ConstValueType;

    /// The const reference type of the map;

    typedef const Value& ConstReferenceType;

    /// The pointer type of the map;

    typedef const Value* ConstPointerType;

  private:

    typedef std::allocator<Value> Allocator;

  public:

    /** Graph and Registry initialized map constructor.

     */

    ArrayMap(const Graph& _g, Registry& _r) : graph(&_g) {

      attach(_r);

      allocate_memory();

      for (KeyIt it(*graph); it != INVALID; ++it) {

	int id = IdMap(*graph)[it];

	allocator.construct(&(values[id]), Value());

      }								

    }

    /// Constructor to use default value to initialize the map. 

    /// It constrates a map and initialize all of the the map. 

    ArrayMap(const Graph& _g, Registry& _r, const Value& _v) : graph(&_g) {

      attach(_r);

      allocate_memory();

      for (KeyIt it(*graph); it != INVALID; ++it) {

	int id = IdMap(*graph)[it];

	allocator.construct(&(values[id]), _v);

      }								

    }

    /** Constructor to copy a map of the same map type.

     */

    ArrayMap(const ArrayMap& copy) {

      if (copy.attached()) {

	attach(*copy.getRegistry());

      }

      capacity = copy.capacity;

      if (capacity == 0) return;

      values = allocator.allocate(capacity);

      for (KeyIt it(*graph); it != INVALID; ++it) {

	int id = IdMap(*graph)[it];

	allocator.construct(&(values[id]), copy.values[id]);

      }

    }

    /** Assign operator to copy a map of the same map type.

     */

    ArrayMap& operator=(const ArrayMap& copy) {

      if (&copy == this) return *this;

      if (graph != copy.graph) {

	if (attached()) {

	  clear();

	  detach();

	}

	if (copy.attached()) {

	  attach(*copy.getRegistry());

	}

	capacity = copy.capacity;

	if (capacity == 0) return *this;

	values = allocator.allocate(capacity);      

      }

      for (KeyIt it(*graph); it != INVALID; ++it) {

	int id = IdMap(*graph)[it];

	allocator.construct(&(values[id]), copy.values[id]);

      }

      return *this;

    }

    /** The destructor of the map.

     */

    virtual ~ArrayMap() {      

      if (attached()) {

	clear();

	detach();

      }

    }

    /**

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

     * actual keys of the graph. 

     */

    ReferenceType operator[](const KeyType& key) {

      int id = IdMap(*graph)[key];

      return values[id];

    } 

    /**

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

     * actual keys of the graph. 

     */

    ConstReferenceType operator[](const KeyType& key) const {

      int id = IdMap(*graph)[key];

      return values[id];

    }

    /** Setter function of the map. Equivalent with map[key] = val.

     *  This is a compatibility feature with the not dereferable maps.

     */

    void set(const KeyType& key, const ValueType& val) {

      (*this)[key] = val;

    }

    /** Add a new key to the map. It called by the map registry.

     */

    void add(const KeyType& key) {

      int id = IdMap(*graph)[key];

      if (id >= capacity) {

	int new_capacity = (capacity == 0 ? 1 : capacity);

	while (new_capacity <= id) {

	  new_capacity <<= 1;

	}

	Value* new_values = allocator.allocate(new_capacity);

	for (KeyIt it(*graph); it != INVALID; ++it) {

	  int jd = IdMap(*graph)[it];

	  if (id != jd) {

	    allocator.construct(&(new_values[jd]), values[jd]);

	    allocator.destroy(&(values[jd]));

	  }

	}

	if (capacity != 0) allocator.deallocate(values, capacity);

	values = new_values;

	capacity = new_capacity;

      }

      allocator.construct(&(values[id]), Value());

    }

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

     */

    void erase(const KeyType& key) {

      int id = IdMap(*graph)[key];

      allocator.destroy(&(values[id]));

    }

    void build() {

      allocate_memory();

      for (KeyIt it(*graph); it != INVALID; ++it) {

	int id = IdMap(*graph)[it];

	allocator.construct(&(values[id]), Value());

      }								

    }

    void clear() {	

      if (capacity != 0) {

	for (KeyIt it(*graph); it != INVALID; ++it) {

	  int id = IdMap(*graph)[it];

	  allocator.destroy(&(values[id]));

	}								

	allocator.deallocate(values, capacity);

	capacity = 0;

      }

    }

//     /// The stl compatible pair iterator of the map.

//     typedef MapIterator<ArrayMap> Iterator;

//     /// The stl compatible const pair iterator of the map.

//     typedef MapConstIterator<ArrayMap> ConstIterator;

//     /** Returns the begin iterator of the map.

//      */

//     Iterator begin() {

//       return Iterator(*this, KeyIt(*MapBase::getGraph()));

//     }

//     /** Returns the end iterator of the map.

//      */

//     Iterator end() {

//       return Iterator(*this, INVALID);

//     }

//     /** Returns the begin ConstIterator of the map.

//      */

//     ConstIterator begin() const {

//       return ConstIterator(*this, KeyIt(*MapBase::getGraph()));

//     }

//     /** Returns the end const_iterator of the map.

//      */

//     ConstIterator end() const {

//       return ConstIterator(*this, INVALID);

//     }

//     /// The KeySet of the Map.

//     typedef MapConstKeySet<ArrayMap> ConstKeySet;

//     /// KeySet getter function.

//     ConstKeySet keySet() const {

//       return ConstKeySet(*this); 

//     }

//     /// The ConstValueSet of the Map.

//     typedef MapConstValueSet<ArrayMap> ConstValueSet;

//     /// ConstValueSet getter function.

//     ConstValueSet valueSet() const {

//       return ConstValueSet(*this);

//     }

//     /// The ValueSet of the Map.

//     typedef MapValueSet<ArrayMap> ValueSet;

//     /// ValueSet getter function.

//     ValueSet valueSet() {

//       return ValueSet(*this);

//     }

  private:

    void allocate_memory() {

      int max_id = IdMap(*graph).maxId();

      if (max_id == -1) {

	capacity = 0;

	values = 0;

	return;

      }

      capacity = 1;

      while (capacity <= max_id) {

	capacity <<= 1;

      }

      values = allocator.allocate(capacity);	

    }      

    const Graph* graph;

    int capacity;

    Value* values;

    Allocator allocator;

  public:

//     // STL  compatibility typedefs.

//     typedef Iterator iterator;

//     typedef ConstIterator const_iterator;

//     typedef typename Iterator::PairValueType value_type;

//     typedef typename Iterator::KeyType key_type;

//     typedef typename Iterator::ValueType data_type;

//     typedef typename Iterator::PairReferenceType reference;

//     typedef typename Iterator::PairPointerType pointer;

//     typedef typename ConstIterator::PairReferenceType const_reference;

//     typedef typename ConstIterator::PairPointerType const_pointer;

//     typedef int difference_type;		

  };		

  template <typename _Base> 

  class ArrayMappableGraphExtender : public _Base {

  public:

    typedef ArrayMappableGraphExtender<_Base> Graph;

    typedef _Base Parent;

    typedef typename Parent::Node Node;

    typedef typename Parent::NodeIt NodeIt;

    typedef typename Parent::NodeIdMap NodeIdMap;

    typedef typename Parent::NodeObserverRegistry NodeObserverRegistry;

    typedef typename Parent::Edge Edge;

    typedef typename Parent::EdgeIt EdgeIt;

    typedef typename Parent::EdgeIdMap EdgeIdMap;

    typedef typename Parent::EdgeObserverRegistry EdgeObserverRegistry;

    template <typename _Value>

    class NodeMap : public ArrayMap<Graph, Node, NodeIt, NodeIdMap, _Value> {

    public:

      typedef ArrayMappableGraphExtender<_Base> Graph;

      typedef typename Graph::Node Node;

      typedef typename Graph::NodeIt NodeIt;

      typedef typename Graph::NodeIdMap NodeIdMap;

      typedef ArrayMap<Graph, Node, NodeIt, NodeIdMap, _Value> Parent;

      typedef typename Parent::Graph Graph;

      typedef typename Parent::Value Value;

      NodeMap(const Graph& g) 

	: Parent(g, g.getNodeObserverRegistry()) {}

      NodeMap(const Graph& g, const Value& v) 

	: Parent(g, g.getNodeObserverRegistry(), v) {}

    };

    template <typename _Value>

    class EdgeMap : public ArrayMap<Graph, Edge, EdgeIt, EdgeIdMap, _Value> {

    public:

      typedef ArrayMappableGraphExtender<_Base> Graph;

      typedef typename Graph::Edge Edge;

      typedef typename Graph::EdgeIt EdgeIt;

      typedef typename Graph::EdgeIdMap EdgeIdMap;

      typedef ArrayMap<Graph, Edge, EdgeIt, EdgeIdMap, _Value> Parent;

      typedef typename Parent::Graph Graph;

      typedef typename Parent::Value Value;

      EdgeMap(const Graph& g) 

	: Parent(g, g.getEdgeObserverRegistry()) {}

      EdgeMap(const Graph& g, const Value& v) 

	: Parent(g, g.getEdgeObserverRegistry(), v) {}

    };

  };

/// @}

}

#endif //LEMON_ARRAY_MAP_H