/*
	This file is part of ct.

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with Takwrap.  If not, see <https://www.gnu.org/licenses/>.
*/

#include "hashtable.h"

// ===================================================================
// Helper declarations
// ===================================================================

ht_entry_t * new_ll_node(const uint64_t key, void *data);

// ===================================================================
// Exported functions
// ===================================================================

hashtable_t *ht_init(void) {
	hashtable_t *table = malloc(sizeof(struct hashtable_s));
	table->num_entries = 0;
	for (uint32_t k=0; k<=HASHTABLE_SIZE; k++)
		table->entries[k] = NULL;
	return EXIT_SUCCESS;
}

void ht_free(void *data_free(void*), hashtable_t *table) {
	ht_entry_t *n, *nn;
	for (uint32_t k=0; k<=HASHTABLE_SIZE; k++) {
		n = table->entries[k];
		while (n) {
			nn = n->next;
			data_free(n->data);
			free(n);
			n = nn;
		}
	}
}

ht_entry_t *ht_seek(const uint64_t key, hashtable_t *table) {
	ht_entry_t *lookup = table->entries[key & HASHTABLE_SIZE];
	while (lookup && lookup->key != key)
		lookup = lookup->next;
	return lookup;
}

int ht_insert(const uint64_t key, void *data, hashtable_t *table) {
	ht_entry_t *new = new_ll_node(key, data), *n;
	// TODO: trap

	const uint32_t idx = key & HASHTABLE_SIZE;
	if ((n = table->entries[idx]) != NULL) {
		for (; n->next != NULL; n = n->next);
		n->next = new;
	} else {
		table->entries[idx] = new;
	}

	table->num_entries++;

	return EXIT_SUCCESS;
}

// ===================================================================
// Helper function implementations
// ===================================================================

ht_entry_t *new_ll_node(const uint64_t key, void *data) {
	ht_entry_t *new = malloc(sizeof(struct ht_node_s));
	// TODO: trap errno
	new->key = key;
	new->next = NULL;
	new->data = data;
	return new;
}