
/******************************************************************************
* MODULE     : hashmap.cpp
* DESCRIPTION: fixed size hashmaps with reference counting
* COPYRIGHT  : (C) 1999  Joris van der Hoeven
*******************************************************************************
* This software falls under the GNU general public license version 3 or later.
* It comes WITHOUT ANY WARRANTY WHATSOEVER. For details, see the file LICENSE
* in the root directory or <http://www.gnu.org/licenses/gpl-3.0.html>.
******************************************************************************/

#ifndef HASHMAP_CC
#define HASHMAP_CC
#include "hashmap.hpp"
#define TMPL template<class T, class U>
#define H hashentry<T,U>

/******************************************************************************
* Hashmap entries
******************************************************************************/

TMPL H::hashentry (int code2, T key2, U im2):
  code (code2), key (key2), im (im2) {}

TMPL H::operator tree () {
  return tree (ASSOCIATE, as_tree(key), as_tree(im)); }

TMPL tm_ostream&
operator << (tm_ostream& out, H h) {
  out << h.key << "->" << h.im;
  return out;
}

TMPL bool
operator == (H h1, H h2) {
  return (h1.code==h2.code) && (h1.key==h2.key) && (h1.im==h2.im);
}

TMPL bool
operator != (H h1, H h2) {
  return (h1.code!=h2.code) || (h1.key!=h2.key) || (h1.im!=h2.im);
}

/******************************************************************************
* Routines for hashmaps
******************************************************************************/

TMPL void
hashmap_rep<T,U>::resize (int n2) {
  int i;
  int oldn= n;
  list<hashentry<T,U> >* olda= a;
  n= n2;
  a= tm_new_array<list<hashentry<T,U> > > (n);
  for (i=0; i<oldn; i++) {
    list<hashentry<T,U> > l(olda[i]);
    while (!is_nil (l)) {
      list<hashentry<T,U> >& newl= a[hash(l->item.key)&(n-1)];
      newl= list<hashentry<T,U> > (l->item, newl);
      l=l->next;
    }
  }
  tm_delete_array (olda);
}

TMPL bool
hashmap_rep<T,U>::contains (T x) {
  register int hv= hash (x);
  list<hashentry<T,U> >  l (a [hv & (n-1)]);
  while (!is_nil (l)) {
    if (l->item.code == hv && l->item.key == x)
      return true;
    l= l->next;
  }
  return false;
}

TMPL bool
hashmap_rep<T,U>::empty () {
  return size==0;
}

TMPL U&
hashmap_rep<T,U>::bracket_rw (T x) {
  register int hv= hash (x);
  list<hashentry<T,U> >  l (a [hv & (n-1)]);
  while (!is_nil (l)) {
    if (l->item.code == hv && l->item.key == x)
      return l->item.im;
    l= l->next;
  }
  if (size >= n*max) resize (n<<1);
  list<hashentry<T,U> >& rl= a [hv & (n-1)];
  rl= list<hashentry<T,U> > (H (hv, x, init), rl);
  size ++;
  return rl->item.im;
}

TMPL U
hashmap_rep<T,U>::bracket_ro (T x) {
  register int hv= hash (x);
  list<hashentry<T,U> >  l (a [hv & (n-1)]);
  while (!is_nil (l)) {
    if (l->item.code == hv && l->item.key == x)
      return l->item.im;
    l= l->next;
  }
  return init;
}

TMPL void
hashmap_rep<T,U>::reset (T x) {
  register int hv= hash (x);
  list<hashentry<T,U> > *l= &(a [hv & (n-1)]);
  while (!is_nil (*l)) {
    if ((*l)->item.code == hv && (*l)->item.key == x) {
      *l= (*l)->next;
      size --;
      if (size < (n>>1) * max) resize (n>>1);
      return;
    }
    l= &((*l)->next);
  }
}

TMPL void
hashmap_rep<T,U>::generate (void (*routine) (T)) {
  int i;
  for (i=0; i<n; i++) {
    list<hashentry<T,U> > l (a[i]);
    while (!is_nil (l)) {
      routine (l->item.key);
      l=l->next;
    }
  }
}

TMPL tm_ostream&
operator << (tm_ostream& out, hashmap<T,U> h) {
  int i= 0, j= 0, n= h->n, size= h->size;
  out << "{ ";
  for (; i<n; i++) {
    list<hashentry<T,U> > l= h->a[i];
    for (; !is_nil (l); l= l->next, j++) {
      out << l->item;
      if (j != size-1) out << ", ";
    }
  }
  out << " }";
  return out;
}

TMPL hashmap<T,U>::operator tree () {
  int i=0, j=0, n=rep->n, size=rep->size;
  tree t (COLLECTION, size);
  for (; i<n; i++) {
    list<hashentry<T,U> > l= rep->a[i];
    for (; !is_nil (l); l= l->next, j++)
      t[j]= (tree) l->item;
  }
  return t;
}

TMPL void
hashmap_rep<T,U>::join (hashmap<T,U> h) {
  int i= 0, n= h->n;
  for (; i<n; i++) {
    list<hashentry<T,U> > l= h->a[i];
    for (; !is_nil(l); l= l->next)
      bracket_rw (l->item.key)= copy (l->item.im);
  }
}

TMPL bool
operator == (hashmap<T,U> h1, hashmap<T,U> h2) {
  if (h1->size != h2->size) return false;
  int i= 0, n= h1->n;
  for (; i<n; i++) {
    list<hashentry<T,U> > l= h1->a[i];
    for (; !is_nil(l); l=l->next)
      if (h2[l->item.key] != l->item.im) return false;
  }
  return true;
}

TMPL bool
operator != (hashmap<T,U> h1, hashmap<T,U> h2) {
  return !(h1 == h2);
}

#undef H
#undef TMPL
#endif // defined HASHMAP_CC
