using System.Globalization;

namespace Kit.Helpers
{
    public class WeekInfo
    {
        public int NumberOfYear { get; set; }
        public DateTime StartDate { get; set; }
        public DateTime EndDate { get; set; }
    }
    public static partial class SystemDateTimeExtensionMethods
    {
        public static string ToStringDateRus(this DateTime dt)
        {
            return dt.ToString("dd.MM.yyyy");
        }

        public static string ToStringDateTimeRus(this DateTime dt)
        {
            return dt.ToString("dd.MM.yyyy hh:mm");
        }

        public static string ToStringTimeRus(this DateTime dt)
        {
            return dt.ToString("hh:mm:ss");
        }


        public static string ToStringDateRus(this DateTime? dt)
        {
            if (dt == null) return String.Empty;
            return dt.ToStringDateRus();
        }

        public static string ToStringDateTimeRus(this DateTime? dt)
        {
            if (dt == null) return String.Empty;
            return dt.Value.ToStringDateTimeRus();
        }

        public static string ToStringTimeRus(this DateTime? dt)
        {
            if (dt == null) return String.Empty;
            return dt.Value.ToStringTimeRus();
        }

        private static CultureInfo cultureRu = new CultureInfo("ru-Ru");
        public static string GetStringMonthYear(this DateTime date)
        {
            return date.ToString("Y");
        }
        //public static DateTime Normolize(this DateTime currentValue)
        //{
        //    return currentValue.Normolize(DateTime.MinValue, DateTime.Now);
        //}

        public static DateTime GetClearTime(this DateTime date)
        {
            return new DateTime(date.Year, date.Month, date.Day);
        }

        private static readonly long DatetimeMinTimeTicks =
        (new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).Ticks;

        public static long ToJavaScriptMilliseconds(this DateTime dt)
        {
            return (long)((dt.ToUniversalTime().Ticks - DatetimeMinTimeTicks) / 10000);
        }


        public static DateTime GetUtcFromDateTime(this DateTime dt, string timezene)
        {
            TimeZoneInfo tzf;
            try
            {
                tzf = TimeZoneInfo.FindSystemTimeZoneById(timezene);
            }
            catch
            {
                tzf = TimeZoneInfo.FindSystemTimeZoneById("Russian Standard Time");
            }
            return TimeZoneInfo.ConvertTimeToUtc(dt, tzf);
        }

        public static DateTime GetDateTimeFromUtc(this DateTime dt, string timezene)
        {
            TimeZoneInfo tzf;
            try
            {
                tzf = TimeZoneInfo.FindSystemTimeZoneById(timezene);
            }
            catch
            {
                tzf = TimeZoneInfo.FindSystemTimeZoneById("Russian Standard Time");
            }
            return TimeZoneInfo.ConvertTimeFromUtc(dt, tzf);
        }


        public static string ToStringOrEmpty(this DateTime? dt, string format)
        {
            if (dt == null) return String.Empty;
            return dt.Value.ToString(format);
        }

        public static string ToStringOrEmpty(this DateTime? dt)
        {
            if (dt == null) return String.Empty;
            return dt.Value.ToString("dd.MM.yyyy");
        }

        public static string ToShortDateStringRu(this DateTime value)
        {
            return value.ToString("dd.MM.yyyy");
        }

        public static string ToShortDateStringUniversal(this DateTime value)
        {
            return value.ToString("yyyy.MM.dd");
        }

        public static string ToStringDMYHMS(this DateTime value)
        {
            return value.ToString("dd.MM.yyyy hh:mm:ss");
        }

        public static string ToShortDateStringRu(this DateTime? value)
        {
            if (value == null) return String.Empty;
            return value.Value.ToShortDateStringRu();
        }

        public static string ToShortDateStringUniversal(this DateTime? value)
        {
            if (value == null) return String.Empty;
            return value.Value.ToShortDateStringUniversal();
        }

        public static string ToStringDMYHMS(this DateTime? value)
        {
            if (value == null) return String.Empty;
            return value.Value.ToStringDMYHMS();
        }

        public static WeekInfo GetInfoWeek(this DateTime? value)
        {
            if (!value.HasValue) return null;
            return value.Value.GetInfoWeek();
        }

        public static WeekInfo GetInfoWeek(this DateTime value)
        {
            var result = new WeekInfo();
            DateTimeFormatInfo dfi = cultureRu.DateTimeFormat;
            Calendar cal = dfi.Calendar;

            result.NumberOfYear = cal.GetWeekOfYear(value, CalendarWeekRule.FirstFullWeek, DayOfWeek.Monday);

            var dtStart = new DateTime(value.Year, 1, 1).AddDays(-(int)(new DateTime(value.Year, 1, 1).DayOfWeek - 1));
            result.StartDate = dtStart.AddDays((result.NumberOfYear - 1) * 7);
            result.EndDate = dtStart.AddDays(result.NumberOfYear * 7);

            return result;
        }

        public static string GetMonthNameRP(this DateTime dt)
        {
            return dt.ToString("MMMMMMMMMMM", cultureRu).Replace("т", "та").Replace("тая", "тя").Replace("й", "я").Replace("ь", "я");
        }

    }
}