/*-
 * Public Domain 2014-2019 MongoDB, Inc.
 * Public Domain 2008-2014 WiredTiger, Inc.
 *
 * This is free and unencumbered software released into the public domain.
 *
 * Anyone is free to copy, modify, publish, use, compile, sell, or
 * distribute this software, either in source code form or as a compiled
 * binary, for any purpose, commercial or non-commercial, and by any
 * means.
 *
 * In jurisdictions that recognize copyright laws, the author or authors
 * of this software dedicate any and all copyright interest in the
 * software to the public domain. We make this dedication for the benefit
 * of the public at large and to the detriment of our heirs and
 * successors. We intend this dedication to be an overt act of
 * relinquishment in perpetuity of all present and future rights to this
 * software under copyright law.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include "cursor_order.h"

static WT_THREAD_RET append_insert(void *);
static void print_stats(SHARED_CONFIG *);
static WT_THREAD_RET reverse_scan(void *);

typedef struct {
    char *name;    /* object name */
    uint64_t nops; /* Thread op count */

    WT_RAND_STATE rnd; /* RNG */

    int append_insert; /* cursor.insert */
    int reverse_scans; /* cursor.prev sequences */
    SHARED_CONFIG *cfg;
} INFO;

static INFO *run_info;

void
ops_start(SHARED_CONFIG *cfg)
{
    struct timeval start, stop;
    wt_thread_t *tids;
    double seconds;
    uint64_t i, name_index, offset, total_nops;

    tids = NULL; /* Keep GCC 4.1 happy. */
    total_nops = 0;

    /* Create per-thread structures. */
    run_info = dcalloc((size_t)(cfg->reverse_scanners + cfg->append_inserters), sizeof(*run_info));
    tids = dcalloc((size_t)(cfg->reverse_scanners + cfg->append_inserters), sizeof(*tids));

    /* Create the files and load the initial records. */
    for (i = 0; i < cfg->append_inserters; ++i) {
        run_info[i].cfg = cfg;
        if (i == 0 || cfg->multiple_files) {
            run_info[i].name = dmalloc(64);
            testutil_check(__wt_snprintf(run_info[i].name, 64, FNAME, (int)i));

            /* Vary by orders of magnitude */
            if (cfg->vary_nops)
                run_info[i].nops = WT_MAX(1000, cfg->max_nops >> i);
            load(cfg, run_info[i].name);
        } else
            run_info[i].name = run_info[0].name;

        /* Setup op count if not varying ops. */
        if (run_info[i].nops == 0)
            run_info[i].nops = cfg->max_nops;
        total_nops += run_info[i].nops;
    }

    /* Setup the reverse scanner configurations */
    for (i = 0; i < cfg->reverse_scanners; ++i) {
        offset = i + cfg->append_inserters;
        run_info[offset].cfg = cfg;
        if (cfg->multiple_files) {
            run_info[offset].name = dmalloc(64);
            /* Have reverse scans read from tables with writes. */
            name_index = i % cfg->append_inserters;
            testutil_check(__wt_snprintf(run_info[offset].name, 64, FNAME, (int)name_index));

            /* Vary by orders of magnitude */
            if (cfg->vary_nops)
                run_info[offset].nops = WT_MAX(1000, cfg->max_nops >> name_index);
        } else
            run_info[offset].name = run_info[0].name;

        /* Setup op count if not varying ops. */
        if (run_info[offset].nops == 0)
            run_info[offset].nops = cfg->max_nops;
        total_nops += run_info[offset].nops;
    }

    (void)gettimeofday(&start, NULL);

    /* Create threads. */
    for (i = 0; i < cfg->reverse_scanners; ++i)
        testutil_check(__wt_thread_create(NULL, &tids[i], reverse_scan, (void *)(uintptr_t)i));
    for (; i < cfg->reverse_scanners + cfg->append_inserters; ++i)
        testutil_check(__wt_thread_create(NULL, &tids[i], append_insert, (void *)(uintptr_t)i));

    /* Wait for the threads. */
    for (i = 0; i < cfg->reverse_scanners + cfg->append_inserters; ++i)
        testutil_check(__wt_thread_join(NULL, &tids[i]));

    (void)gettimeofday(&stop, NULL);
    seconds = (stop.tv_sec - start.tv_sec) + (stop.tv_usec - start.tv_usec) * 1e-6;
    fprintf(stderr, "timer: %.2lf seconds (%d ops/second)\n", seconds,
      (int)(((double)(cfg->reverse_scanners + cfg->append_inserters) * total_nops) / seconds));

    /* Verify the files. */
    for (i = 0; i < cfg->reverse_scanners + cfg->append_inserters; ++i) {
        verify(cfg, run_info[i].name);
        if (!cfg->multiple_files)
            break;
    }

    /* Output run statistics. */
    print_stats(cfg);

    /* Free allocated memory. */
    for (i = 0; i < cfg->reverse_scanners + cfg->append_inserters; ++i) {
        free(run_info[i].name);
        if (!cfg->multiple_files)
            break;
    }

    free(run_info);
    free(tids);
}

/*
 * reverse_scan_op --
 *     Walk a cursor back from the end of the file.
 */
static inline void
reverse_scan_op(SHARED_CONFIG *cfg, WT_SESSION *session, WT_CURSOR *cursor, INFO *s)
{
    uint64_t i, initial_key_range, prev_key, this_key;
    int ret;
    char *strkey;

    WT_UNUSED(session);
    WT_UNUSED(s);

    /* Make GCC 4.1 happy */
    prev_key = this_key = 0;

    /* Reset the cursor */
    testutil_check(cursor->reset(cursor));

    /* Save the key range. */
    initial_key_range = cfg->key_range - cfg->append_inserters;

    for (i = 0; i < cfg->reverse_scan_ops; i++) {
        if ((ret = cursor->prev(cursor)) != 0) {
            if (ret == WT_NOTFOUND)
                break;
            testutil_die(ret, "cursor.prev");
        }

        if (cfg->ftype == ROW) {
            testutil_check(cursor->get_key(cursor, &strkey));
            this_key = (uint64_t)atol(strkey);
        } else
            testutil_check(cursor->get_key(cursor, (uint64_t *)&this_key));

        if (i == 0 && this_key < initial_key_range)
            testutil_die(ret,
              "cursor scan start range wrong first prev %" PRIu64 " initial range: %" PRIu64,
              this_key, initial_key_range);
        if (i != 0 && this_key >= prev_key)
            testutil_die(
              ret, "cursor scan out of order this: %" PRIu64 " prev: %" PRIu64, this_key, prev_key);
        prev_key = this_key;
    }
}

/*
 * reverse_scan --
 *     Reader thread start function.
 */
static WT_THREAD_RET
reverse_scan(void *arg)
{
    INFO *s;
    SHARED_CONFIG *cfg;
    WT_CURSOR *cursor;
    WT_SESSION *session;
    uintmax_t id;
    uint64_t i;
    char tid[128];

    id = (uintmax_t)arg;
    s = &run_info[id];
    cfg = s->cfg;
    testutil_check(__wt_thread_str(tid, sizeof(tid)));
    __wt_random_init(&s->rnd);

    printf(" reverse scan thread %2" PRIuMAX " starting: tid: %s, file: %s\n", id, tid, s->name);

    __wt_yield(); /* Get all the threads created. */

    testutil_check(cfg->conn->open_session(cfg->conn, NULL, "isolation=snapshot", &session));
    testutil_check(session->open_cursor(session, s->name, NULL, NULL, &cursor));
    for (i = 0; i < s->nops && !cfg->thread_finish; ++i, ++s->reverse_scans, __wt_yield())
        reverse_scan_op(cfg, session, cursor, s);
    testutil_check(session->close(session, NULL));

    printf(" reverse scan thread %2" PRIuMAX " stopping: tid: %s, file: %s\n", id, tid, s->name);

    /* Notify all other threads to finish once the first thread is done */
    cfg->thread_finish = true;

    return (WT_THREAD_RET_VALUE);
}

/*
 * append_insert_op --
 *     Write operation.
 */
static inline void
append_insert_op(SHARED_CONFIG *cfg, WT_SESSION *session, WT_CURSOR *cursor, INFO *s)
{
    WT_ITEM *value, _value;
    size_t len;
    uint64_t keyno;
    char keybuf[64], valuebuf[64];

    WT_UNUSED(session);

    value = &_value;

    keyno = __wt_atomic_add64(&cfg->key_range, 1);
    if (cfg->ftype == ROW) {
        testutil_check(__wt_snprintf(keybuf, sizeof(keybuf), "%016" PRIu64, keyno));
        cursor->set_key(cursor, keybuf);
    } else
        cursor->set_key(cursor, (uint32_t)keyno);

    ++s->append_insert;
    value->data = valuebuf;
    if (cfg->ftype == FIX)
        cursor->set_value(cursor, 0x10);
    else {
        testutil_check(
          __wt_snprintf_len_set(valuebuf, sizeof(valuebuf), &len, "XXX %37" PRIu64, keyno));
        value->size = (uint32_t)len;
        cursor->set_value(cursor, value);
    }
    testutil_check(cursor->insert(cursor));
}

/*
 * append_insert --
 *     Writer thread start function.
 */
static WT_THREAD_RET
append_insert(void *arg)
{
    INFO *s;
    SHARED_CONFIG *cfg;
    WT_CURSOR *cursor;
    WT_SESSION *session;
    uintmax_t id;
    uint64_t i;
    char tid[128];

    id = (uintmax_t)arg;
    s = &run_info[id];
    cfg = s->cfg;
    testutil_check(__wt_thread_str(tid, sizeof(tid)));
    __wt_random_init(&s->rnd);

    printf("write thread %2" PRIuMAX " starting: tid: %s, file: %s\n", id, tid, s->name);

    __wt_yield(); /* Get all the threads created. */

    testutil_check(cfg->conn->open_session(cfg->conn, NULL, "isolation=snapshot", &session));
    testutil_check(session->open_cursor(session, s->name, NULL, NULL, &cursor));
    for (i = 0; i < s->nops && !cfg->thread_finish; ++i, __wt_yield())
        append_insert_op(cfg, session, cursor, s);
    testutil_check(session->close(session, NULL));

    printf("write thread %2" PRIuMAX " stopping: tid: %s, file: %s\n", id, tid, s->name);

    /* Notify all other threads to finish once the first thread is done */
    cfg->thread_finish = true;

    return (WT_THREAD_RET_VALUE);
}

/*
 * print_stats --
 *     Display reverse scan/writer thread stats.
 */
static void
print_stats(SHARED_CONFIG *cfg)
{
    INFO *s;
    uint64_t id, total_threads;

    total_threads = cfg->reverse_scanners + cfg->append_inserters;
    s = run_info;
    for (id = 0; id < total_threads; ++id, ++s)
        printf("%3d: reverse scans %6d, append inserts %6d\n", (int)id, (int)s->reverse_scans,
          (int)s->append_insert);
}