#include "time_sync.h"

#include <stdbool.h>
#include <stdlib.h>
#include <time.h>

#include "esp_log.h"
#include "esp_netif_sntp.h"
#include "sdkconfig.h"

static const char *TAG = "sese_time";
static bool s_initialized;

static void log_local_time(const char *prefix)
{
    time_t now;
    struct tm local_time;
    char timestamp[40];

    time(&now);
    localtime_r(&now, &local_time);
    if (strftime(timestamp, sizeof(timestamp), "%Y-%m-%dT%H:%M:%S%z", &local_time) == 0) {
        ESP_LOGW(TAG, "%s, but timestamp formatting failed", prefix);
        return;
    }
    ESP_LOGI(TAG, "%s: %s", prefix, timestamp);
}

static void time_sync_notification(struct timeval *time_value)
{
    (void)time_value;
    log_local_time("NTP time synchronized");
}

esp_err_t time_sync_start(void)
{
    if (s_initialized) {
        return ESP_OK;
    }

    if (setenv("TZ", CONFIG_SESE_TIMEZONE, 1) != 0) {
        return ESP_FAIL;
    }
    tzset();

    esp_sntp_config_t config = ESP_NETIF_SNTP_DEFAULT_CONFIG(CONFIG_SESE_NTP_SERVER);
    config.sync_cb = time_sync_notification;
    esp_err_t err = esp_netif_sntp_init(&config);
    if (err != ESP_OK) {
        return err;
    }

    s_initialized = true;
    ESP_LOGI(TAG, "NTP started with server '%s' and timezone '%s'",
             CONFIG_SESE_NTP_SERVER, CONFIG_SESE_TIMEZONE);
    return ESP_OK;
}

esp_err_t time_sync_wait(TickType_t timeout)
{
    if (!s_initialized) {
        return ESP_ERR_INVALID_STATE;
    }

    esp_err_t err = esp_netif_sntp_sync_wait(timeout);
    if (err == ESP_OK) {
        log_local_time("Initial system time ready");
    } else if (err == ESP_ERR_TIMEOUT) {
        ESP_LOGW(TAG, "Initial NTP synchronization timed out; periodic retries remain active");
    } else {
        ESP_LOGW(TAG, "Initial NTP synchronization did not complete: %s", esp_err_to_name(err));
    }
    return err;
}