#include "git-compat-util.h"
#include "hashmap.h"

struct test_entry
{
        struct hashmap_entry ent;
        /* key and value as two \0-terminated strings */
        char key[FLEX_ARRAY];
};

static const char *get_value(const struct test_entry *e)
{
        return e->key + strlen(e->key) + 1;
}

static int test_entry_cmp(const void *unused_cmp_data,
                          const struct test_entry *e1,
                          const struct test_entry *e2,
                          const char* key)
{
        return strcmp(e1->key, key ? key : e2->key);
}

static int test_entry_cmp_icase(const void *unused_cmp_data,
                                const struct test_entry *e1,
                                const struct test_entry *e2,
                                const char* key)
{
        return strcasecmp(e1->key, key ? key : e2->key);
}

static struct test_entry *alloc_test_entry(int hash, char *key, int klen,
                char *value, int vlen)
{
        struct test_entry *entry = malloc(sizeof(struct test_entry) + klen
                        + vlen + 2);
        hashmap_entry_init(entry, hash);
        memcpy(entry->key, key, klen + 1);
        memcpy(entry->key + klen + 1, value, vlen + 1);
        return entry;
}

#define HASH_METHOD_FNV 0
#define HASH_METHOD_I 1
#define HASH_METHOD_IDIV10 2
#define HASH_METHOD_0 3
#define HASH_METHOD_X2 4
#define TEST_SPARSE 8
#define TEST_ADD 16
#define TEST_SIZE 100000

static unsigned int hash(unsigned int method, unsigned int i, const char *key)
{
        unsigned int hash = 0;
        switch (method & 3)
        {
        case HASH_METHOD_FNV:
                hash = strhash(key);
                break;
        case HASH_METHOD_I:
                hash = i;
                break;
        case HASH_METHOD_IDIV10:
                hash = i / 10;
                break;
        case HASH_METHOD_0:
                hash = 0;
                break;
        }

        if (method & HASH_METHOD_X2)
                hash = 2 * hash;
        return hash;
}

/*
 * Test performance of hashmap.[ch]
 * Usage: time echo "perfhashmap method rounds" | test-hashmap
 */
static void perf_hashmap(unsigned int method, unsigned int rounds)
{
        struct hashmap map;
        char buf[16];
        struct test_entry **entries;
        unsigned int *hashes;
        unsigned int i, j;

        entries = malloc(TEST_SIZE * sizeof(struct test_entry *));
        hashes = malloc(TEST_SIZE * sizeof(int));
        for (i = 0; i < TEST_SIZE; i++) {
                snprintf(buf, sizeof(buf), "%i", i);
                entries[i] = alloc_test_entry(0, buf, strlen(buf), "", 0);
                hashes[i] = hash(method, i, entries[i]->key);
        }

        if (method & TEST_ADD) {
                /* test adding to the map */
                for (j = 0; j < rounds; j++) {
                        hashmap_init(&map, (hashmap_cmp_fn) test_entry_cmp,
                                     NULL, 0);

                        /* add entries */
                        for (i = 0; i < TEST_SIZE; i++) {
                                hashmap_entry_init(entries[i], hashes[i]);
                                hashmap_add(&map, entries[i]);
                        }

                        hashmap_free(&map, 0);
                }
        } else {
                /* test map lookups */
                hashmap_init(&map, (hashmap_cmp_fn) test_entry_cmp, NULL, 0);

                /* fill the map (sparsely if specified) */
                j = (method & TEST_SPARSE) ? TEST_SIZE / 10 : TEST_SIZE;
                for (i = 0; i < j; i++) {
                        hashmap_entry_init(entries[i], hashes[i]);
                        hashmap_add(&map, entries[i]);
                }

                for (j = 0; j < rounds; j++) {
                        for (i = 0; i < TEST_SIZE; i++) {
                                hashmap_get_from_hash(&map, hashes[i],
                                                      entries[i]->key);
                        }
                }

                hashmap_free(&map, 0);
        }
}

#define DELIM " \t\r\n"

/*
 * Read stdin line by line and print result of commands to stdout:
 *
 * hash key -> strhash(key) memhash(key) strihash(key) memihash(key)
 * put key value -> NULL / old value
 * get key -> NULL / value
 * remove key -> NULL / old value
 * iterate -> key1 value1\nkey2 value2\n...
 * size -> tablesize numentries
 *
 * perfhashmap method rounds -> test hashmap.[ch] performance
 */
int cmd_main(int argc, const char **argv)
{
        char line[1024];
        struct hashmap map;
        int icase;

        /* init hash map */
        icase = argc > 1 && !strcmp("ignorecase", argv[1]);
        hashmap_init(&map, (hashmap_cmp_fn) (icase ? test_entry_cmp_icase
                        : test_entry_cmp), NULL, 0);

        /* process commands from stdin */
        while (fgets(line, sizeof(line), stdin)) {
                char *cmd, *p1 = NULL, *p2 = NULL;
                int l1 = 0, l2 = 0, hash = 0;
                struct test_entry *entry;

                /* break line into command and up to two parameters */
                cmd = strtok(line, DELIM);
                /* ignore empty lines */
                if (!cmd || *cmd == '#')
                        continue;

                p1 = strtok(NULL, DELIM);
                if (p1) {
                        l1 = strlen(p1);
                        hash = icase ? strihash(p1) : strhash(p1);
                        p2 = strtok(NULL, DELIM);
                        if (p2)
                                l2 = strlen(p2);
                }

                if (!strcmp("hash", cmd) && l1) {

                        /* print results of different hash functions */
                        printf("%u %u %u %u\n", strhash(p1), memhash(p1, l1),
                                        strihash(p1), memihash(p1, l1));

                } else if (!strcmp("add", cmd) && l1 && l2) {

                        /* create entry with key = p1, value = p2 */
                        entry = alloc_test_entry(hash, p1, l1, p2, l2);

                        /* add to hashmap */
                        hashmap_add(&map, entry);

                } else if (!strcmp("put", cmd) && l1 && l2) {

                        /* create entry with key = p1, value = p2 */
                        entry = alloc_test_entry(hash, p1, l1, p2, l2);

                        /* add / replace entry */
                        entry = hashmap_put(&map, entry);

                        /* print and free replaced entry, if any */
                        puts(entry ? get_value(entry) : "NULL");
                        free(entry);

                } else if (!strcmp("get", cmd) && l1) {

                        /* lookup entry in hashmap */
                        entry = hashmap_get_from_hash(&map, hash, p1);

                        /* print result */
                        if (!entry)
                                puts("NULL");
                        while (entry) {
                                puts(get_value(entry));
                                entry = hashmap_get_next(&map, entry);
                        }

                } else if (!strcmp("remove", cmd) && l1) {

                        /* setup static key */
                        struct hashmap_entry key;
                        hashmap_entry_init(&key, hash);

                        /* remove entry from hashmap */
                        entry = hashmap_remove(&map, &key, p1);

                        /* print result and free entry*/
                        puts(entry ? get_value(entry) : "NULL");
                        free(entry);

                } else if (!strcmp("iterate", cmd)) {

                        struct hashmap_iter iter;
                        hashmap_iter_init(&map, &iter);
                        while ((entry = hashmap_iter_next(&iter)))
                                printf("%s %s\n", entry->key, get_value(entry));

                } else if (!strcmp("size", cmd)) {

                        /* print table sizes */
                        printf("%u %u\n", map.tablesize, map.size);

                } else if (!strcmp("intern", cmd) && l1) {

                        /* test that strintern works */
                        const char *i1 = strintern(p1);
                        const char *i2 = strintern(p1);
                        if (strcmp(i1, p1))
                                printf("strintern(%s) returns %s\n", p1, i1);
                        else if (i1 == p1)
                                printf("strintern(%s) returns input pointer\n", p1);
                        else if (i1 != i2)
                                printf("strintern(%s) != strintern(%s)", i1, i2);
                        else
                                printf("%s\n", i1);

                } else if (!strcmp("perfhashmap", cmd) && l1 && l2) {

                        perf_hashmap(atoi(p1), atoi(p2));

                } else {

                        printf("Unknown command %s\n", cmd);

                }
        }

        hashmap_free(&map, 1);
        return 0;
}