#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include <assert.h>

/* wrap the whole module */
#include "lru_cache.c"

static unsigned int g_verbose_ = 0;

struct test_kv_cache_entry {
	struct lru_cache_entry lru_;

	char key[128];
	char value[128];
};
typedef struct test_kv_cache_entry kve_t;

static
void
test_kv_hash_feed(lru_entry_t *entry, char **bufp, size_t *szp)
{
	struct test_kv_cache_entry *e = (struct test_kv_cache_entry *)entry;
	*bufp = e->key;
	*szp = sizeof e->key;
}

static
int
test_kv_cmp(lru_entry_t *a, lru_entry_t *b)
{
	kve_t *kv_a = (kve_t *)a,
	      *kv_b = (kve_t *)b;

	return strcmp(kv_a->key, kv_b->key);
}

static
void
kv_dump(struct lru_cache *c)
{
	struct test_kv_cache_entry *kve;
	lru_entry_t *e;
	size_t i;

	fprintf(stderr, "\nLRU, %zu entries\n", c->num_entries);

	if (g_verbose_ == 0)
		return;

	fprintf(stderr, "-- hash --\n");
	for (i = 0; i < c->hash_sz; i++) {
		int s;
		for (s = 0, e = c->hash[i].entry; e; e = e->hash_next, s++) {
			kve = (struct test_kv_cache_entry *)e;
			if (e != NULL) {
				if (e->hash_slot != i)
					fprintf(stderr, "!!! sanity failure, entry has hash slot %zu, but is in slot %zu !!!\n", e->hash_slot, i);
				fprintf(stderr, "%*s[%zu]: (%p) '%s':'%s'\n", s, "", i, kve, kve->key, kve->value);
			}
		}
	}

	fprintf(stderr, "-- queue --\n");
	for (e = c->newest; e; e = e->next) {
		kve = (struct test_kv_cache_entry *)e;
		fprintf(stderr, "(%p) '%s':'%s'\n", kve, kve->key, kve->value);
	}

	fprintf(stderr, "\n");
}

void
kv_genstats(lru_entry_t *e, size_t i, void *data)
{
	struct test_kv_cache_entry *kve = (struct test_kv_cache_entry *)e;
	size_t *hash_depth = (size_t *)data;
	(void)i, (void)kve;

	hash_depth[e->hash_slot]++;
}
void
kv_dumpstats(struct lru_cache *c, size_t *stats, size_t sz)
{
	size_t i;

	for (i = 0; i < sz; i++)
		fprintf(stderr, "slot %04zu: %zu (expect: %zu)\n", i, stats[i], c->hash[i].tally);
}

int
main(int argc, char *argv[])
{
	const size_t hash_sz = 31;
	const size_t capacity = 256;

	struct lru_cache *cache;
	struct test_kv_cache_entry *e, *r, m;
	int i;

	size_t *stats;

	while ( (i = getopt(argc, argv, "vh")) != EOF ) {
		switch (i) {
			case 'v':
				g_verbose_++;
				break;

			case 'h':
			default:
				exit(EXIT_FAILURE);
		}
	}

	stats = malloc(hash_sz * sizeof *stats);
	memset(stats, 0, hash_sz * sizeof *stats);

	cache = lru_cache_new(hash_sz, capacity, test_kv_hash_feed, test_kv_cmp);
	assert(cache != NULL);

	kv_dump(cache);

	e = malloc(sizeof *e);
	assert(e != NULL);

	strncpy(e->key, "key", sizeof e->key);
	strncpy(e->value, "value", sizeof e->value);

	lru_cache_insert(cache, (lru_entry_t *)e, (lru_entry_t **)&r);
	assert(r == NULL);

	kv_dump(cache);

	memset(&m, 0, sizeof m);
	strncpy(m.key, "key", sizeof e->key);
	e = (struct test_kv_cache_entry *)lru_cache_locate(cache, (lru_entry_t *)&m);
	assert(e != NULL);

	lru_cache_extract(cache, (lru_entry_t *)e);
	free(e);

	kv_dump(cache);

	for (i = 0; i < 500; i++) {
		r = NULL;
		e = malloc(sizeof *e);
		assert(e != NULL);
		memset(e, 0, sizeof *e);
		snprintf(e->key, sizeof e->key, "test %d key", i);
		snprintf(e->value, sizeof e->value, "some %d value", i);
		lru_cache_insert(cache, (lru_entry_t *)e, (lru_entry_t **)&r);
		if (r) {
			if (g_verbose_)
				fprintf(stderr, "freeing (%p) '%s':'%s'\n", r, r->key, r->value);
			free(r);
		}
	}

	kv_dump(cache);

	for (i = 0; i < 500; i += 3) {
		memset(&m, 0, sizeof m);
		snprintf(m.key, sizeof m.key, "test %d key", i);
		e = (struct test_kv_cache_entry *)lru_cache_locate(cache, (lru_entry_t *)&m);
		if (e == NULL) {
			if (g_verbose_)
				fprintf(stderr, "key %d was not cached\n", i);
			continue;
		}
		lru_cache_extract(cache, (lru_entry_t *)e);
		if (g_verbose_)
			fprintf(stderr, "extracted '%s'\n", e->key);
		free(e);
	}

	kv_dump(cache);

	for (i = 0; i < 10; i += 2) {
		e = malloc(sizeof *e);
		assert(e != NULL);
		memset(e, 0, sizeof *e);
		snprintf(e->key, sizeof e->key, "new key %d", i);
		snprintf(e->value, sizeof e->value, "new value %d", i);
		lru_cache_insert(cache, (lru_entry_t *)e, (lru_entry_t **)&r);
		if (r) {
			if (g_verbose_)
				fprintf(stderr, "freeing (%p) '%s':'%s'\n", r, r->key, r->value);
			free(r);
		}
	}

	kv_dump(cache);

	lru_cache_foreach(cache, kv_genstats, stats);
	kv_dumpstats(cache, stats, hash_sz);

	exit(EXIT_SUCCESS);
}