#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include "sntp_timp.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_log.h"
#include "esp_idf_version.h"
#include "esp_sntp.h"
#include "esp_netif_sntp.h"
#include "sys/time.h"
#include "esp_timer.h"

static const char *TAG = "sntp_timp";

#define SNTP_TIME_VALID_UNIX_TS 1700000000
#define SNTP_WAIT_POLL_MS 200
#define SNTP_REFRESH_PERIOD_MS 1000

extern void set_var_sntp_time(const char *value) __attribute__((weak));

static TaskHandle_t s_time_refresh_task = NULL;

static time_t get_current_time(void);

static void publish_sntp_time_var(const char *value)
{
    if (set_var_sntp_time != NULL) {
        set_var_sntp_time(value);
    }
}

static void format_current_time(char *buffer, size_t buffer_size)
{
    time_t now = get_current_time();
    struct tm timeinfo;

    localtime_r(&now, &timeinfo);
    strftime(buffer, buffer_size, "%Y-%m-%d %H:%M:%S", &timeinfo);
}

static void sntp_time_refresh_task(void *arg)
{
    (void)arg;

    char time_text[32];
    for (;;) {
        format_current_time(time_text, sizeof(time_text));
        publish_sntp_time_var(time_text);
        vTaskDelay(pdMS_TO_TICKS(SNTP_REFRESH_PERIOD_MS));
    }
}

// =========================== 时间相关函数 ===========================
static void set_timezone(void)
{
    // 设置中国标准时间（北京时间）
    setenv("TZ", "CST-8", 1);
    tzset();
    ESP_LOGI(TAG, "时区设置为北京时间 (CST-8)");
}

static time_t get_current_time(void)
{
    // 使用POSIX函数获取时间
    return time(NULL);
}

static void print_current_time(void)
{
    char buffer[64];
    format_current_time(buffer, sizeof(buffer));

    ESP_LOGI(TAG, "当前时间: %s", buffer);
}

static esp_err_t start_time_refresh_task_if_needed(void)
{
    if (s_time_refresh_task != NULL) {
        return ESP_OK;
    }

    BaseType_t ok = xTaskCreate(sntp_time_refresh_task,
                                "sntp_time",
                                3072,
                                NULL,
                                3,
                                &s_time_refresh_task);
    return (ok == pdPASS) ? ESP_OK : ESP_ERR_NO_MEM;
}

static void configure_sntp_servers(void)
{
    ESP_LOGI(TAG, "初始化SNTP服务");

#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 0, 0)
    esp_sntp_setoperatingmode(SNTP_OPMODE_POLL);
    esp_sntp_setservername(0, "cn.pool.ntp.org"); // 中国 NTP 服务器
    esp_sntp_setservername(1, "ntp1.aliyun.com"); // 阿里云 NTP 服务器
#else
    sntp_setoperatingmode(SNTP_OPMODE_POLL);
    sntp_setservername(0, "cn.pool.ntp.org");
    sntp_setservername(1, "cn.pool.ntp.org");
    sntp_setservername(2, "ntp1.aliyun.com");
#endif
}

static esp_err_t wait_for_time_sync(uint32_t timeout_ms)
{
    int64_t start_ms = esp_timer_get_time() / 1000;
    for (;;) {
        time_t now = get_current_time();
        if (now >= SNTP_TIME_VALID_UNIX_TS) {
            return ESP_OK;
        }

        int64_t elapsed_ms = (esp_timer_get_time() / 1000) - start_ms;
        if (elapsed_ms >= (int64_t)timeout_ms) {
            return ESP_ERR_TIMEOUT;
        }

        vTaskDelay(pdMS_TO_TICKS(SNTP_WAIT_POLL_MS));
    }
}

esp_err_t sntp_timp_sync_time(uint32_t timeout_ms)
{
    if (timeout_ms == 0) {
        timeout_ms = 10000;
    }

    set_timezone();

    if (esp_sntp_enabled()) {
        esp_sntp_stop();
    }

    configure_sntp_servers();
    esp_sntp_init();

    esp_err_t ret = wait_for_time_sync(timeout_ms);
    if (ret == ESP_OK) {
        print_current_time();
        char time_text[32];
        format_current_time(time_text, sizeof(time_text));
        publish_sntp_time_var(time_text);

        esp_err_t task_ret = start_time_refresh_task_if_needed();
        if (task_ret != ESP_OK) {
            ESP_LOGW(TAG, "创建时间刷新任务失败: %s", esp_err_to_name(task_ret));
        }
    } else {
        ESP_LOGW(TAG, "SNTP 对时超时（%lu ms）", (unsigned long)timeout_ms);
    }

    return ret;
}