// -*- c++ -*-

 #ifndef ARRAY_MAP_H

 #define ARRAY_MAP_H

 #include <memory>

 #include <hugo/map_iterator.h>

 ///\ingroup graphmaps

 ///\file

 ///\brief Graph maps that construates and destruates

 ///their elements dynamically.

 namespace hugo {

   /// \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 MapRegistry, typename Value> 

   class ArrayMap : public MapRegistry::MapBase {

   public:

     /// The graph type of the maps. 

     typedef typename MapRegistry::Graph Graph;

     /// The key type of the maps.

     typedef typename MapRegistry::KeyType KeyType;

     /// The iterator to iterate on the keys.

     typedef typename MapRegistry::KeyIt KeyIt;

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

     typedef typename MapRegistry::MapBase MapBase;

   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;

     typedef std::allocator<Value> Allocator;

     /** Default constructor for the map.

      */

     ArrayMap() : values(0), capacity(0) {}

     /** Graph and Registry initialized map constructor.

      */

     ArrayMap(const Graph& g, MapRegistry& r) : MapBase(g, r) {

       allocate_memory();

       for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	int id = MapBase::getGraph()->id(it);

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

       }								

     }

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

      */

     ArrayMap(const Graph& g, MapRegistry& r, const Value& v) 

       : MapBase(g, r) {

       allocate_memory();

       for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	int id = MapBase::getGraph()->id(it);

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

       }								

     }

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

      */

     ArrayMap(const ArrayMap& copy) : MapBase(*copy.graph, *copy.registry) {

       capacity = copy.capacity;

       if (capacity == 0) return;

       values = allocator.allocate(capacity);

       for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	int id = MapBase::getGraph()->id(it);

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

       }

     }

     /** Constructor to copy a map of an other map type.

      */

     template <typename CMap> ArrayMap(const CMap& copy) 

       : MapBase(copy), capacity(0), values(0) {

       if (MapBase::getGraph()) {

 	allocate_memory();

 	for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	  set(it, copy[it]);

 	}

       }

     }

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

      */

     ArrayMap& operator=(const ArrayMap& copy) {

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

       if (capacity != 0) {

 	MapBase::destroy();

 	allocator.deallocate(values, capacity);

       }

       capacity = copy.capacity;

       if (capacity == 0) return *this;

       values = allocator.allocate(capacity);

       for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	int id = MapBase::getGraph()->id(it);

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

       }

       return *this;

     }

     /** Assign operator to copy a map an other map type.

      */

     template <typename CMap> ArrayMap& operator=(const CMap& copy) {

       if (MapBase::getGraph()) {

 	MapBase::destroy();

       } 

       MapBase::operator=(copy);

       if (MapBase::getGraph()) {

 	allocate_memory();

 	for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	  set(it, copy[it]);

 	}

       }

       return *this;

     }

     /** The destructor of the map.

      */

     virtual ~ArrayMap() {

       if (capacity != 0) {

 	MapBase::destroy();

 	allocator.deallocate(values, capacity);

       }

     }

     /**

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

      * actual keys of the graph. 

      */

     ReferenceType operator[](const KeyType& key) {

       int id = MapBase::getGraph()->id(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 = MapBase::getGraph()->id(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) {

       int id = MapBase::getGraph()->id(key);

       values[id] = val;

     }

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

      */

     void add(const KeyType& key) {

       int id = MapBase::getGraph()->id(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(*MapBase::getGraph()); it != INVALID; ++it) {

 	  int jd = MapBase::getGraph()->id(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 = MapBase::getGraph()->id(key);

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

     }

     /** Clear the data structure.

      */

     void clear() {	

       if (capacity != 0) {

 	MapBase::destroy();

 	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);

     }

   private:

     void allocate_memory() {

       int max_id = -1;

       for (KeyIt it(*MapBase::getGraph()); it != INVALID; ++it) {

 	int id = MapBase::getGraph()->id(it);

 	if (id > max_id) {

 	  max_id = id;

 	}			

       }

       if (max_id == -1) {

 	capacity = 0;

 	values = 0;

 	return;

       }

       capacity = 1;

       while (capacity <= max_id) {

 	capacity <<= 1;

       }

       values = allocator.allocate(capacity);	

     }      

     int capacity;

     Value* values;

     Allocator allocator;

   };		

 /// @}

 }

 #endif