using System;
using System.Runtime.InteropServices;

namespace Hncore.Infrastructure.Common
{
    public class DateTimeHelper
    {
        public static DateTime SqlMinTime => Convert.ToDateTime("1975-01-01 00:00:00");

        public static DateTime SqlMaxTime => Convert.ToDateTime("9999-12-31 23:59:59");

        /// <summary>
        /// 将10位时间戳转时间
        /// </summary>
        /// <param name="unixTimeStamp"></param>
        /// <returns></returns>
        public static DateTime UnixTimeStampToDateTime(long unixTimeStamp)
        {
            // Unix timestamp is seconds past epoch
            DateTime dtDateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
            dtDateTime = dtDateTime.AddSeconds(unixTimeStamp).ToLocalTime();
            return dtDateTime;
        }

        public static long ToUnixTimestamp(DateTime target)
        {
            return Convert.ToInt64((TimeZoneInfo.ConvertTimeToUtc(target) -
                                    new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc)).TotalSeconds);
        }

        /// <summary>
        /// 将13位时间戳转为时间
        /// </summary>
        /// <param name="javaTimeStamp"></param>
        /// <returns></returns>
        public static DateTime JsTimeStampToDateTime(double javaTimeStamp)
        {
            var dtDateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
            dtDateTime = dtDateTime.AddMilliseconds(javaTimeStamp).ToLocalTime();
            return dtDateTime;
        }

        /// <summary>
        /// 获取时间戳
        /// </summary>
        /// <param name="target"></param>
        /// <param name="bflag">为真时获取10位时间戳,为假时获取13位时间戳</param>
        /// <returns></returns>
        public static long ToUnixTime(DateTime target, bool bflag = false)
        {
            TimeSpan ts = target - new DateTime(1970, 1, 1, 0, 0, 0, 0);
            long timer = 0;
            timer = Convert.ToInt64(!bflag ? ts.TotalSeconds : ts.TotalMilliseconds);
            return timer;
        }

        public static TimeZoneInfo GetCstTimeZoneInfo()
        {
            if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
            {
                return TimeZoneInfo.FindSystemTimeZoneById("Asia/Shanghai");
            }

            return TimeZoneInfo.FindSystemTimeZoneById("China Standard Time");
        }

        public static bool IsSameDayOrLess(DateTime dt1, DateTime dt2)
        {
            return dt1.Year == dt2.Year
                && dt1.Month == dt2.Month
                && dt1.Day == dt2.Day
                || dt1 < dt2;
        }

        public static DateTime GetDatePart(DateTime dt)
        {
            return new DateTime(dt.Year, dt.Month, dt.Day);
        }
    }
}