/* -*- mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*- */
// vim: ft=cpp:expandtab:ts=8:sw=4:softtabstop=4:
#ident "$Id$"
/*======
This file is part of PerconaFT.


Copyright (c) 2006, 2015, Percona and/or its affiliates. All rights reserved.

    PerconaFT is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2,
    as published by the Free Software Foundation.

    PerconaFT 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 PerconaFT.  If not, see <http://www.gnu.org/licenses/>.

----------------------------------------

    PerconaFT is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License, version 3,
    as published by the Free Software Foundation.

    PerconaFT 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 Affero General Public License for more details.

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

#ident "Copyright (c) 2006, 2015, Percona and/or its affiliates. All rights reserved."

#include "test.h"

// test a comparison function that treats certain different-lengthed keys as equal

struct packed_key {
    char type;
    char k[8];
    static packed_key as_int(int v) {
        packed_key k;
        k.type = 0;
        memcpy(k.k, &v, sizeof(int));
        return k;
    }
    static packed_key as_double(double v) {
        packed_key k;
        k.type = 1;
        memcpy(k.k, &v, sizeof(double));
        return k;
    }
    size_t size() const {
        assert(type == 0 || type == 1);
        return type == 0 ? 5 : 9;
    }
};

// the point is that keys can be packed as integers or doubles, but
// we'll treat them both as doubles for the sake of comparison.
// this means a 4 byte number could equal an 8 byte number.
static int packed_key_cmp(DB *UU(db), const DBT *a, const DBT *b) {
    assert(a->size == 5 || a->size == 9);
    assert(b->size == 5 || b->size == 9);
    char *k1 = reinterpret_cast<char *>(a->data);
    char *k2 = reinterpret_cast<char *>(b->data);
    assert(*k1 == 0 || *k1 == 1);
    assert(*k2 == 0 || *k2 == 1);
    double v1 = *k1 == 0 ? static_cast<double>(*reinterpret_cast<int *>(k1 + 1)) :
                           *reinterpret_cast<double *>(k1 + 1);
    double v2 = *k2 == 0 ? static_cast<double>(*reinterpret_cast<int *>(k2 + 1)) :
                           *reinterpret_cast<double *>(k2 + 1);
    if (v1 > v2) {
        return 1;
    } else if (v1 < v2) {
        return -1;
    } else {
        return 0;
    }
}

static int update_callback(DB *UU(db), const DBT *UU(key), const DBT *old_val, const DBT *extra,
                           void (*set_val)(const DBT *new_val, void *setval_extra), void *setval_extra) {
    assert(extra != nullptr);
    assert(old_val != nullptr);
    assert(extra->size == 0 || extra->size == 100);
    assert(old_val->size == 0 || old_val->size == 100);
    if (extra->data == nullptr) {
        set_val(nullptr, setval_extra);
    } else {
        set_val(extra, setval_extra);
    }
    return 0;
}

enum overwrite_method { 
    VIA_UPDATE_OVERWRITE_BROADCAST,
    VIA_UPDATE_DELETE_BROADCAST,
    VIA_UPDATE_OVERWRITE,
    VIA_UPDATE_DELETE,
    VIA_DELETE,
    VIA_INSERT,
    NUM_OVERWRITE_METHODS
};

static void test_keylen_diff(enum overwrite_method method, bool control_test) {
    int r;

    DB_ENV *env;
    r = db_env_create(&env, 0); CKERR(r);
    r = env->set_default_bt_compare(env, packed_key_cmp); CKERR(r);
    env->set_update(env, update_callback); CKERR(r);
    r = env->open(env, TOKU_TEST_FILENAME, DB_CREATE+DB_PRIVATE+DB_INIT_MPOOL+DB_INIT_TXN, 0); CKERR(r);

    DB *db;
    r = db_create(&db, env, 0); CKERR(r);
    r = db->set_pagesize(db, 16 * 1024); // smaller pages so we get a more lush tree
    r = db->set_readpagesize(db, 1 * 1024); // smaller basements so we get more per leaf
    r = db->open(db, nullptr, "db", nullptr, DB_BTREE, DB_CREATE, 0666); CKERR(r);

    DBT null_dbt, val_dbt;
    char val_buf[100];
    memset(val_buf, 0, sizeof val_buf);
    dbt_init(&val_dbt, &val_buf, sizeof val_buf);
    dbt_init(&null_dbt, nullptr, 0);

    const int num_keys = 1<<11; //256 * 1000;

    for (int i = 0; i < num_keys; i++) {
        // insert it using a 4 byte key ..
        packed_key key = packed_key::as_int(i);

        DBT dbt;
        dbt_init(&dbt, &key, key.size());
        r = db->put(db, nullptr, &dbt, &val_dbt, 0); CKERR(r);
    }

    // overwrite keys randomly, so we induce flushes and get better / realistic coverage
    int *XMALLOC_N(num_keys, shuffled_keys);
    for (int i = 0; i < num_keys; i++) {
        shuffled_keys[i] = i;
    }
    for (int i = num_keys - 1; i >= 1; i--) {
        long rnd = random64() % (i + 1);
        int tmp = shuffled_keys[rnd];
        shuffled_keys[rnd] = shuffled_keys[i];
        shuffled_keys[i] = tmp;
    }

    for (int i = 0; i < num_keys; i++) {
        // for the control test, delete it using the same length key
        //
        // .. otherwise, delete it with an 8 byte key
        packed_key key = control_test ? packed_key::as_int(shuffled_keys[i]) :
                                        packed_key::as_double(shuffled_keys[i]);

        DBT dbt;
        dbt_init(&dbt, &key, key.size());
        DB_TXN *txn;
        env->txn_begin(env, nullptr, &txn, DB_TXN_NOSYNC); CKERR(r);
        switch (method) {
            case VIA_INSERT: {
                r = db->put(db, txn, &dbt, &val_dbt, 0); CKERR(r);
                break;
            }
            case VIA_DELETE: {
                // we purposefully do not pass DB_DELETE_ANY because the hidden query acts as
                // a sanity check for the control test and, overall, gives better code coverage
                r = db->del(db, txn, &dbt, 0); CKERR(r);
                break;
            }
            case VIA_UPDATE_OVERWRITE:
            case VIA_UPDATE_DELETE: {
                r = db->update(db, txn, &dbt, method == VIA_UPDATE_DELETE ? &null_dbt : &val_dbt, 0); CKERR(r);
                break;
            }
            case VIA_UPDATE_OVERWRITE_BROADCAST:
            case VIA_UPDATE_DELETE_BROADCAST: {
                r = db->update_broadcast(db, txn, method == VIA_UPDATE_DELETE_BROADCAST ? &null_dbt : &val_dbt, 0); CKERR(r);
                if (i > 1 ) { // only need to test broadcast twice - one with abort, one without
                    txn->abort(txn); // we opened a txn so we should abort it before exiting
                    goto done;
                }
                break;
            }
            default: {
                assert(false);
            }
        }
        const bool abort = i % 2 == 0;
        if (abort) {
            txn->abort(txn);
        } else {
            txn->commit(txn, 0);
        }
    }

done:
    toku_free(shuffled_keys);

    // optimize before close to ensure that all messages are applied and any potential bugs are exposed
    r = db->optimize(db);
    r = db->close(db, 0); CKERR(r);
    r = env->close(env, 0); CKERR(r);
}

int
test_main(int argc, char *const argv[]) {
    parse_args(argc, argv);

    toku_os_recursive_delete(TOKU_TEST_FILENAME);
    int r = toku_os_mkdir(TOKU_TEST_FILENAME, S_IRWXU+S_IRWXG+S_IRWXO); CKERR(r);

    for (int i = 0; i < NUM_OVERWRITE_METHODS; i++) {
        enum overwrite_method method = static_cast<enum overwrite_method>(i);

        // control test - must pass for the 'real' test below to be interesting
        printf("testing method %d (control)\n", i);
        test_keylen_diff(method, true);

        // real test, actually mixes key lengths
        printf("testing method %d (real)\n", i);
        test_keylen_diff(method, false);
    }

    return 0;
}