/* -*- C++ -*-
 * lemon/bits/array_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_ARRAY_MAP_H
#define LEMON_ARRAY_MAP_H

#include <memory>
#include <lemon/bits/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 AlterationNotifier that the maps
  /// will belong to and the Value.
   

  template <typename _Graph, 
	    typename _Item,
	    typename _Value>
  class ArrayMap : public AlterationNotifier<_Item>::ObserverBase {

    typedef _Item Item;
  public:
		
    /// The graph type of the maps. 
    typedef _Graph Graph;
    /// The key type of the maps.
    typedef _Item Key;

    typedef AlterationNotifier<_Item> Registry;

    /// The MapBase of the Map which imlements the core regisitry function.
    typedef typename Registry::ObserverBase Parent;
		
    /// The value type of the map.
    typedef _Value Value;


  private:
    typedef std::allocator<Value> Allocator;


  public:

    /// Graph and Registry initialized map constructor.
     
    ArrayMap(const Graph& _g) : graph(&_g) {
      Item it;
      attach(_g.getNotifier(Item()));
      allocate_memory();
      for (graph->first(it); it != INVALID; graph->next(it)) {
	int id = graph->id(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, const Value& _v) : graph(&_g) {
      Item it;
      attach(_g.getNotifier(_Item()));
      allocate_memory();
      for (graph->first(it); it != INVALID; graph->next(it)) {
	int id = graph->id(it);;
	allocator.construct(&(values[id]), _v);
      }								
    }

    /// Constructor to copy a map of the same map type.
     
    ArrayMap(const ArrayMap& copy) : Parent() {
      if (copy.attached()) {
	attach(*copy.getRegistry());
      }
      capacity = copy.capacity;
      if (capacity == 0) return;
      values = allocator.allocate(capacity);
      Item it;
      for (graph->first(it); it != INVALID; graph->next(it)) {
	int id = graph->id(it);;
	allocator.construct(&(values[id]), copy.values[id]);
      }
    }

    using Parent::attach;
    using Parent::detach;
    using Parent::attached;

    /// 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);      
      }

      Item it;
      for (graph->first(it); it != INVALID; graph->next(it)) {
	int id = graph->id(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. 
     
    Value& operator[](const Key& key) {
      int id = graph->id(key);
      return values[id];
    } 
		

    ///The const subscript operator. The map can be subscripted by the
    ///actual keys of the graph. 
     
    const Value& operator[](const Key& key) const {
      int id = graph->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 Key& key, const Value& val) {
      (*this)[key] = val;
    }
		
    /// Add a new key to the map. It called by the map registry.
     
    void add(const Key& key) {
      int id = graph->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);
	Item it;
	for (graph->first(it); it != INVALID; graph->next(it)) {
	  int jd = graph->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());
    }

    void add(const std::vector<Key>& keys) {
      int max_id = -1;
      for (int i = 0; i < (int)keys.size(); ++i) {
	int id = graph->id(keys[i]);
	if (id > max_id) {
	  max_id = id;
	}
      }
      if (max_id >= capacity) {
	int new_capacity = (capacity == 0 ? 1 : capacity);
	while (new_capacity <= max_id) {
	  new_capacity <<= 1;
	}
	Value* new_values = allocator.allocate(new_capacity);
	Item it;
	for (graph->first(it); it != INVALID; graph->next(it)) {
	  int id = graph->id(it);
	  bool found = false;
	  for (int i = 0; i < (int)keys.size(); ++i) {
	    int jd = graph->id(keys[i]);
	    if (id == jd) {
	      found = true;
	      break;
	    }
	  }
	  if (found) continue;
	  allocator.construct(&(new_values[id]), values[id]);
	  allocator.destroy(&(values[id]));
	}
	if (capacity != 0) allocator.deallocate(values, capacity);
	values = new_values;
	capacity = new_capacity;
      }
      for (int i = 0; i < (int)keys.size(); ++i) {
	int id = graph->id(keys[i]);
	allocator.construct(&(values[id]), Value());
      }
    }
		
    /// Erase a key from the map. It called by the map registry.
     
    void erase(const Key& key) {
      int id = graph->id(key);
      allocator.destroy(&(values[id]));
    }

    void erase(const std::vector<Key>& keys) {
      for (int i = 0; i < (int)keys.size(); ++i) {
	int id = graph->id(keys[i]);
	allocator.destroy(&(values[id]));
      }
    }

    void build() {
      allocate_memory();
      Item it;
      for (graph->first(it); it != INVALID; graph->next(it)) {
	int id = graph->id(it);;
	allocator.construct(&(values[id]), Value());
      }								
    }

    void clear() {	
      if (capacity != 0) {
	Item it;
	for (graph->first(it); it != INVALID; graph->next(it)) {
	  int id = graph->id(it);
	  allocator.destroy(&(values[id]));
	}								
	allocator.deallocate(values, capacity);
	capacity = 0;
      }
    }

    const Graph* getGraph() {
      return graph;
    }

  private:
      
    void allocate_memory() {
      int max_id = graph->maxId(_Item());
      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;

  };		

  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::NodeNotifier NodeObserverRegistry;

    typedef typename Parent::Edge Edge;
    typedef typename Parent::EdgeIt EdgeIt;
    typedef typename Parent::EdgeNotifier EdgeObserverRegistry;

    

    template <typename _Value>
    class NodeMap 
      : public IterableMapExtender<ArrayMap<Graph, Node, _Value> > {
    public:
      typedef ArrayMappableGraphExtender<_Base> Graph;

      typedef typename Graph::Node Node;
      typedef typename Graph::NodeIt NodeIt;

      typedef IterableMapExtender<ArrayMap<Graph, Node, _Value> > Parent;

      //typedef typename Parent::Graph Graph;
      typedef typename Parent::Value Value;

      NodeMap(const Graph& g) 
	: Parent(g) {}
      NodeMap(const Graph& g, const Value& v) 
	: Parent(g, v) {}

    };

    template <typename _Value>
    class EdgeMap 
      : public IterableMapExtender<ArrayMap<Graph, Edge, _Value> > {
    public:
      typedef ArrayMappableGraphExtender<_Base> Graph;

      typedef typename Graph::Edge Edge;
      typedef typename Graph::EdgeIt EdgeIt;

      typedef IterableMapExtender<ArrayMap<Graph, Edge, _Value> > Parent;

      //typedef typename Parent::Graph Graph;
      typedef typename Parent::Value Value;

      EdgeMap(const Graph& g) 
	: Parent(g) {}
      EdgeMap(const Graph& g, const Value& v) 
	: Parent(g, v) {}

    };
    
  };

/// @}

}

#endif //LEMON_ARRAY_MAP_H