/*
 * Copyright (c) 2021 Huawei Technologies Co.,Ltd.
 *
 * openGauss is licensed under Mulan PSL v2.
 * You can use this software according to the terms and conditions of the Mulan PSL v2.
 * You may obtain a copy of Mulan PSL v2 at:
 *
 *          http://license.coscl.org.cn/MulanPSL2
 *
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PSL v2 for more details.
 * -------------------------------------------------------------------------
 *
 * cm_timer.c
 *
 *
 * IDENTIFICATION
 *    src/common/cm_time/cm_timer.c
 *
 * -------------------------------------------------------------------------
 */

#include "cm_timer.h"
#include "cm_log.h"

#define DAY_USECS (uint64)86400000000
static gs_timer_t g_timer_t;
static gs_timer_t *g_register_timer = NULL;

gs_timer_t *g_timer()
{
    if (g_register_timer != NULL) {
        return g_register_timer;
    }
    return &g_timer_t;
}

static inline int32 cm_get_time_zone()
{
#ifdef WIN32
    TIME_ZONE_INFORMATION tmp;
    GetTimeZoneInformation(&tmp);
    return tmp.Bias * (-1);
#else
    time_t t = time(NULL);
    struct tm now_time;
    (void)localtime_r(&t, &now_time);

    return (int32)(now_time.tm_gmtoff / SECONDS_PER_MIN);
#endif
}

static void timer_proc(thread_t *thread)
{
    date_t start_time;
    gs_timer_t *timer_temp = (gs_timer_t *)thread->argument;
    int16 tz_min;

    start_time = cm_now();

    (void)cm_set_thread_name("dcf_timer");

#ifndef _WIN32
    struct timespec tq, tr;
    tq.tv_sec = 0;
    tq.tv_nsec = 100000; // 0.1ms
#endif

    while (!thread->closed) {
        cm_now_detail((date_detail_t *)&timer_temp->detail);
        timer_temp->now = cm_encode_date((const date_detail_t *)&timer_temp->detail);
        timer_temp->today = (timer_temp->now / (int64)DAY_USECS) * (int64)DAY_USECS;
        timer_temp->systime = (uint32)((timer_temp->now - start_time) / (int64)MICROSECS_PER_SECOND);

        // flush timezone
        tz_min = (int16)cm_get_time_zone();
        timer_temp->tz = tz_min / 60;
        timer_temp->host_tz_offset = tz_min * 60 * 1000000LL;
#ifdef _WIN32
        cm_sleep(1);
#else
        (void)nanosleep(&tq, &tr);
#endif
    }
}

status_t cm_start_timer(gs_timer_t *input_timer)
{
    if (g_register_timer != NULL) {
        return CM_SUCCESS;
    }

    cm_now_detail((date_detail_t *)&input_timer->detail);
    input_timer->now = cm_encode_date((const date_detail_t *)&input_timer->detail);
    input_timer->today = (date_t)(input_timer->now / (int64)DAY_USECS) * (int64)DAY_USECS;
    input_timer->systime = 0;
    int16 tz_min = (int16)cm_get_time_zone();
    input_timer->tz = tz_min / (int32)SECONDS_PER_MIN;
    input_timer->host_tz_offset = tz_min * SECONDS_PER_MIN * MICROSECS_PER_SECOND_LL;
    return cm_create_thread(timer_proc, 0, input_timer, &input_timer->thread);
}

void cm_close_timer(gs_timer_t *input_timer)
{
    if (g_register_timer != NULL) {
        return;
    }
    cm_close_thread(&input_timer->thread);
}

void cm_set_timer(gs_timer_t *input_timer)
{
    g_register_timer = input_timer;
}