#include <caml/mlvalues.h>
#include <caml/callback.h>
#include <caml/alloc.h>
#include <caml/memory.h>

#include "ht.h"

struct hashtable {
  value v;
};

static struct hashtable * ht_alloc (value v)
{
  struct hashtable * wrapper = malloc(sizeof(struct hashtable));
  if (wrapper == NULL) return NULL;
  wrapper->v = v;
  caml_register_global_root(&(wrapper->v));
  return wrapper;
}

void ht_free (struct hashtable * ht)
{
  caml_remove_global_root(&(ht->v));
  free(ht);
}

struct hashtable * ht_create (void) {
 static value *create_closure = NULL;
 if (create_closure == NULL)
   create_closure = caml_named_value("create");
 return ht_alloc(caml_callback(*create_closure, Val_unit));
}

void ht_add (struct hashtable * ht, char *key, int val) {
 static value *add_closure = NULL;
 if (add_closure == NULL)
   add_closure = caml_named_value("add");
 caml_callback3(*add_closure, ht->v, caml_copy_string(key), Val_int(val));
}

void ht_mem (struct hashtable * ht, char *key) {
 static value *mem_closure = NULL;
 if (mem_closure == NULL)
   mem_closure = caml_named_value("mem");
 caml_callback2(*mem_closure, ht->v, caml_copy_string(key));
}

void ht_remove (struct hashtable * ht, char *key) {
 static value *remove_closure = NULL;
 if (remove_closure == NULL)
   remove_closure = caml_named_value("remove");
 caml_callback2(*remove_closure, ht->v, caml_copy_string(key));
}