using System.Runtime.InteropServices;

namespace SiNan.Common.Extensions
{
    public static class DateTimeExtension
    {
        private static readonly DateTime beginTime = new DateTime(1970, 1, 1, 0, 0, 0, 0);

        /// <summary>
        /// 时间戳转时间
        /// </summary>
        /// <param name="timeStamp">时间</param>
        /// <param name="len13">true:13, false:10</param>
        /// <returns></returns>
        [Obsolete]
        public static DateTime StampToDateTime(this long timeStamp)
        {
            DateTime dt = TimeZone.CurrentTimeZone.ToLocalTime(beginTime);
            return timeStamp.ToString().Length == 13 ? dt.AddMilliseconds(timeStamp) : dt.AddSeconds(timeStamp);
        }

        /// <summary>
        /// 时间转时间戳
        /// </summary>
        /// <param name="time">时间</param>
        /// <param name="len13">true:13, false:10</param>
        /// <returns></returns>
        public static long DateTimeToStamp(this DateTime time, bool len13 = true)
        {
            TimeSpan ts = time.ToUniversalTime() - beginTime;
            if (len13)
                return Convert.ToInt64(ts.TotalMilliseconds);
            else
                return Convert.ToInt64(ts.TotalSeconds);
        }

        /// <summary>
        /// 将秒数转换为时分秒形式
        /// </summary>
        /// <param name="second"></param>
        /// <returns></returns>
        public static string FormatToHHmmss(long second)
        {
            if (second < 60)
                return $"00:00:{(second >= 10 ? $"{second}" : $"0{second}")}";
            if (second < 3600)
            {
                var minute = second / 60;
                var s = second % 60;
                return $"00:{(minute >= 10 ? $"{minute}" : $"0{minute}")}:{(s >= 10 ? $"{s}" : $"0{s}")}";
            }
            else
            {
                var hour = second / 3600;
                var minute = (second - (hour * 3600)) / 60;
                var s = (second - ((hour * 3600) + minute * 60)) % 60;
                return $"{(hour >= 10 ? $"{hour}" : $"0{hour}")}:{(minute >= 10 ? $"{minute}" : $"0{minute}")}:{(s >= 10 ? $"{s}" : $"0{s}")}";
            }
        }

        #region SetLocalTime
        [DllImport("Kernel32.dll")]
        private static extern bool SetLocalTime(ref SYSTEMTIME lpSystemTime);

        [StructLayout(LayoutKind.Sequential)]
        private struct SYSTEMTIME
        {
            public ushort wYear;
            public ushort wMonth;
            public ushort wDayOfWeek;
            public ushort wDay;
            public ushort wHour;
            public ushort wMinute;
            public ushort wSecond;
            public ushort wMilliseconds;
        }

        /// <summary>
        /// 修改系统时间(需要管理员权限)
        /// </summary>
        /// <param name="date"></param>
        public static void SetSystemTime(DateTime date)
        {
            SYSTEMTIME lpTime = new SYSTEMTIME();
            lpTime.wYear = Convert.ToUInt16(date.Year);
            lpTime.wMonth = Convert.ToUInt16(date.Month);
            lpTime.wDayOfWeek = Convert.ToUInt16(date.DayOfWeek);
            lpTime.wDay = Convert.ToUInt16(date.Day);
            DateTime time = date;
            lpTime.wHour = Convert.ToUInt16(time.Hour);
            lpTime.wMinute = Convert.ToUInt16(time.Minute);
            lpTime.wSecond = Convert.ToUInt16(time.Second);
            lpTime.wMilliseconds = Convert.ToUInt16(time.Millisecond);
            var r = SetLocalTime(ref lpTime);
            Console.WriteLine($"修改系统时间 {r}");
        }
        #endregion
    }
}