#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

#include "map.h"

void *alloc(size_t nmemb, size_t size)
{
	void *p;
	p = calloc(nmemb, size);
	if (p == NULL) {
		perror("calloc");
		exit(1);
	}
	return p;
}

void *ralloc(void *p, size_t size)
{
	p = realloc(p, size);
	if (p == NULL) {
		perror("realloc");
		exit(1);
	}
	return p;
}

static size_t hash(const void *src, size_t len)
{
	const unsigned char *d = (const unsigned char *)src;
	size_t h = 0xcbf29ce484222325;
	size_t i;
	for (i = 0; i < len; i++) {
		h ^= d[i];
		h *= 0x100000001b3;
	}
	return h;
}

void map_init(MAP *m)
{
	m->cap = 100;
	m->len = 0;
	m->list = alloc(m->cap, sizeof(NODE*));
}

static NODE *mapn_new(const void *key, size_t ksize, const void *val, size_t vsize)
{
	NODE *n;
	n = alloc(1, sizeof(NODE));
	n->key = alloc(1, ksize);
	n->ksize = ksize;
	memcpy(n->key, key, ksize);
	n->val = alloc(1, vsize);
	n->vsize = vsize;
	memcpy(n->val, val, vsize);
	return n;
}

static void mapn_setv(NODE *n, const void *val, size_t vsize)
{
	n->val = ralloc(n->val, vsize);
	n->vsize = vsize;
	memcpy(n->val, val, vsize);
}

void map_set(MAP *m, const void *key, size_t ksize, const void *val, size_t vsize)
{
	size_t h;
	NODE *n, *next;
	h = hash(key, ksize);
	h = h % m->cap;
	n = m->list[h];
	if (n != NULL) {
		if (n->ksize == ksize && memcmp(n->key, key, n->ksize) == 0) {
			mapn_setv(n, val, vsize);
		} else {
			next = mapn_new(key, ksize, val, vsize);
			n->next = next;
			m->len++;
		}
		return;
	}
	n = mapn_new(key, ksize, val, vsize);
	m->list[h] = n;
	m->len++;
}

int map_get(MAP *m, const void *key, size_t ksize, void **val, size_t *vsize)
{
	size_t h;
	NODE *n;
	int ok;
	h = hash(key, ksize);
	h = h % m->cap;
	n = m->list[h];
	if (n == NULL)
		return -1;
	ok = 0;
	while (1) {
		if (n->ksize == ksize && memcmp(n->key, key, n->ksize) == 0) {
			ok = 1;
			break;
		}
		if (n->next == NULL) {
			break;
		}
		n = n->next;
	}
	if (!ok)
		return -1;
	*val = n->val;
	*vsize = n->vsize;
	return 0;
}