/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
// vim: ft=cpp:expandtab:ts=8:sw=4:softtabstop=4:

// Test cardinality algorithm on a 2 level key where the first level is identical and the second level is unique

#ident "Copyright (c) 2013 Tokutek Inc.  All rights reserved."
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <memory.h>
#include <assert.h>
#include <errno.h>
#include <db.h>
#if __linux__
#include <endian.h>
#endif
#include <sys/stat.h>
typedef unsigned long long ulonglong;
#include "tokudb_status.h"
#include "tokudb_buffer.h"
#include "fake_mysql.h"
#if __APPLE__
typedef unsigned long ulong;
#endif
#include "tokudb_card.h"

static uint32_t hton32(uint32_t n) {
#if BYTE_ORDER == LITTLE_ENDIAN
    return __builtin_bswap32(n);
#else
    return n;
#endif
}

struct key {
    uint32_t k0;
    uint32_t seq;
}; //  __attribute__((packed));

struct val {
    uint32_t v0;
}; //  __attribute__((packed));

// load nrows into the db
static void load_db(DB_ENV *env, DB *db, uint32_t nrows) {
    DB_TXN *txn = NULL;
    int r = env->txn_begin(env, NULL, &txn, 0);
    assert(r == 0);

    DB_LOADER *loader = NULL;
    uint32_t db_flags[1] = { 0 };
    uint32_t dbt_flags[1] = { 0 };
    uint32_t loader_flags = 0;
    r = env->create_loader(env, txn, &loader, db, 1, &db, db_flags, dbt_flags, loader_flags);
    assert(r == 0);

    for (uint32_t seq = 0; seq < nrows ; seq++) {
        struct key k = { 0, hton32(seq) };
        struct val v = { seq };
        DBT key = { .data = &k, .size = sizeof k };
        DBT val = { .data = &v, .size = sizeof v };
        r = loader->put(loader, &key, &val);
        assert(r == 0);
    }

    r = loader->close(loader);
    assert(r == 0);

    r = txn->commit(txn, 0);
    assert(r == 0);
}

static int analyze_key_compare(DB *db __attribute__((unused)), const DBT *a, const DBT *b, uint level) {
    assert(a->size == b->size);
    switch (level) {
    default:
        assert(0);
    case 1:
        return memcmp(a->data, b->data, sizeof (uint32_t));
    case 2:
        assert(a->size == sizeof (struct key));
        return memcmp(a->data, b->data, sizeof (struct key));
    }
}

static void test_card(DB_ENV *env, DB *db, uint64_t expect[]) {
    int r;
    
    DB_TXN *txn = NULL;
    r = env->txn_begin(env, NULL, &txn, 0);
    assert(r == 0);

    uint64_t num_key_parts = 2;
    uint64_t rec_per_key[num_key_parts];

    r = tokudb::analyze_card(db, txn, false, num_key_parts, rec_per_key, analyze_key_compare, NULL, NULL);
    assert(r == 0);

    assert(rec_per_key[0] == expect[0]);
    assert(rec_per_key[1] == expect[1]);

    r = txn->commit(txn, 0);
    assert(r == 0);
}

int main(int argc, char * const argv[]) {
    uint64_t nrows = 1000000;
    for (int i = 1; i < argc; i++) {
        if (strcmp(argv[i], "--nrows") == 0 && i+1 < argc) {
            nrows = atoll(argv[++i]);
            continue;
        }
    }

    int r;
    r = system("rm -rf " __FILE__ ".testdir");
    assert(r == 0);
    r = mkdir(__FILE__ ".testdir", S_IRWXU+S_IRWXG+S_IRWXO);
    assert(r == 0);

    DB_ENV *env = NULL;
    r = db_env_create(&env, 0);
    assert(r == 0);

    r = env->open(env, __FILE__ ".testdir", DB_INIT_MPOOL + DB_INIT_LOG + DB_INIT_LOCK + DB_INIT_TXN + DB_PRIVATE + DB_CREATE, S_IRWXU+S_IRWXG+S_IRWXO); 
    assert(r == 0);

    // create the db
    DB *db = NULL;
    r = db_create(&db, env, 0);
    assert(r == 0);

    r = db->open(db, NULL, "test.db", 0, DB_BTREE, DB_CREATE + DB_AUTO_COMMIT, S_IRWXU+S_IRWXG+S_IRWXO);
    assert(r == 0);

    // load the db
    load_db(env, db, nrows);

    uint64_t expect[2] = { nrows, 1 };
    test_card(env, db, expect);

    r = db->close(db, 0);
    assert(r == 0);

    r = env->close(env, 0);
    assert(r == 0);

    return 0;
}