namespace SJZY.Track.Application.Helpers;

public static class DateTimeHelper
{
    /// <summary>
    /// convert to a Unix timestamp from a DateTime object.
    /// </summary>
    /// <param name="dateTime">The DateTime object to convert to a Unix timestamp.</param>
    /// <returns>The Unix timestamp as a long.</returns>
    public static long ConvertToUnixTimestamp(DateTime dateTime)
    {
        return new DateTimeOffset(dateTime).ToUnixTimeSeconds();
    }

    /// <summary>
    /// Formats a DateTime object into a specified format.
    /// </summary>
    /// <param name="dateTime">The DateTime object to format.</param>
    /// <param name="format">The format string.</param>
    /// <returns>The formatted date string.</returns>
    public static string FormatDateTime(DateTime dateTime, string format)
    {
        return dateTime.ToString(format);
    }

    /// <summary>
    /// 时区格式化
    /// </summary>
    /// <param name="timezone"></param>
    /// <param name="format"></param>
    /// <returns></returns>
    public static string TimezoneFormat(double timezone, string format)
    {
        //时区是整数丢掉浮点数部分
        return format.Replace("hh", ((int) timezone).ToString());
    }

    /// <summary>
    /// 转换主数据中心类似GMT-09:00这种的时区为浮点数
    /// </summary>
    /// <param name="timeZone">分区</param>
    /// <returns></returns>
    /// <exception cref="ArgumentException"></exception>
    public static float? ConvertTimeZoneToFloat(string timeZone)
    {
        if (string.IsNullOrEmpty(timeZone) || !timeZone.StartsWith("GMT"))
        {
            return null;
        }

        var sign = timeZone[3] == '+' ? 1 : -1;
        var parts = timeZone.Substring(4).Split(':');
        var hours = int.Parse(parts[0]);
        var minutes = int.Parse(parts[1]);

        return sign * (hours + minutes / 60f);
    }

    /// <summary>
    /// 将浮点数时区转换为GMT格式
    /// 如果为null则返回"--"
    /// </summary>
    /// <param name="timezone"></param>
    /// <returns></returns>
    public static string ConvertFloatToTimeZone(float? timezone)
    {
        if (timezone == null) return "--";

        if (Math.Abs(timezone.Value - GlobalConst.NoneTrackTimeZone) < 0.01f) return "--";

        if (Math.Abs(timezone.Value) < 0.01f) return "GMT +00:00";

        // 将小数形式的小时转换为时区偏移量
        var hours = (int) timezone.Value; // 提取整数部分作为小时
        var minutes = (int) ((timezone.Value - hours) * 60); // 将小数部分乘以 60 转换为分钟
        var offset = new TimeSpan(hours, minutes, 0);
        var timeZoneStr = offset.ToString();
        var flag = timezone > 0f ? "+" : "";
        return $"GMT {flag}{timeZoneStr.RemovePostFix(":00")}";
    }
}