#include "HashTable.h"
#include "bool.h"

template <class KEY, class DATA>
KEY
HashEntry<KEY, DATA>::getKey(void)
{
  return _key;
}


template <class KEY, class DATA>
DATA
HashEntry<KEY, DATA>::getData(void)
{
  return _data;
}


template <class KEY, class DATA>
HashEntry<KEY, DATA> *
HashEntry<KEY, DATA>::getNext(void)
{
  return _next;
}


template <class KEY, class DATA>
HashTable<KEY, DATA>::HashTable(int size, int (*hash_fn)(KEY), 
				int (*key_eq)(KEY,KEY))
{
  _numElts = 0;
  _size = size;
  _hashFn = hash_fn;
  _eqFn = key_eq;

  _table = new HashEntry<KEY, DATA> *[_size];
  for (int i = 0; i < _size; i++)
    _table[i] = NULL;
}


template <class KEY, class DATA>
HashTable<KEY, DATA>::~HashTable()
{
  HashEntry<KEY, DATA> *trav, *next;
  
  for (int i = 0; i < _size; i++) {
    _trav = _table[i];
    while(_trav) {
      _next = trav->_next;
      delete trav;
      trav = next;
    }
  }
   
  delete [] _table;
}


template <class KEY, class DATA>
int
HashTable<KEY, DATA>::size(void)
{
  return _size;
}


template <class KEY, class DATA>
int
HashTable<KEY, DATA>::numElements(void)
{
  return _numElts;
}


template <class KEY, class DATA>
int
HashTable<KEY, DATA>::find(KEY key, DATA *data)
{
  HashEntry<KEY, DATA> *trav;

  trav = _table[_hashFn(key) % _size];
  
  while ((trav != NULL) && !_eqFn(key, trav->_key))
    trav = trav->_next;

  if (trav == NULL)
    return FALSE;
  else {
    if (data)
      *data = trav->_data;
    return TRUE;
  }
}


template <class KEY, class DATA>
HashEntry<KEY, DATA> *
HashTable<KEY, DATA>::getBucket(KEY key)
{
  return _table[_hashFn(key) % _size];
}


template <class KEY, class DATA>
void
HashTable<KEY, DATA>::insert(KEY key, DATA data)
{
  int hash_val = _hashFn(key) % _size;
  HashEntry<KEY, DATA> *entry = new HashEntry<KEY, DATA>;
  
  entry->_key = key;
  entry->_data = data;
  entry->_next = _table[hash_val];
  _table[hash_val] = entry;

  _numElts++;
}