using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace IStation.Model.Monitor
{
    /// <summary>
    /// 年段
    /// </summary>
    public class YearSlot : JsonModel<YearSlot>, ICronSlot
    {
        /// <summary>
        /// 是否从前一年开始
        /// </summary>
        public bool Pre { get; set; }

        /// <summary>
        /// 开始月数 1-12
        /// </summary>
        public int Start { get; set; } = 1;

        /// <summary>
        /// 结束月数 1-12
        /// </summary>
        public int End { get; set; } = 12;

        /// <summary>
        /// 验证
        /// </summary>
        public bool Verify()
        {
            if (this.Start < 1 || this.Start > 12)
                return false;
            if (this.End < 1 || this.End > 12)
                return false;
            var start = this.Start;
            var end = this.End;
            if (this.Pre)
            {
                end += 12;
            }

            if (end - start < 1)
                return false;
            if (end - start > 11)
                return false;

            return true;
        }

        /// <summary>
        /// 获取开始时间
        /// </summary>
        public DateTime GetStartTime(DateTime rhs)
        {
            var start = 1;
            if (Verify())
            {
                start = this.Start;
                if (Pre)
                    start = start - 12;
            }
            var dt = rhs.AddYears(-1);
            dt = new DateTime(dt.Year, 1, 1);
            dt = dt.AddMonths(start).AddMonths(-1);
            dt = dt.Date;
            return dt;
        }

        /// <summary>
        /// 获取结束时间
        /// </summary>
        public DateTime GetEndTime(DateTime rhs)
        {
            var end = 12;
            if (Verify())
                end = this.End;
            var dt = rhs.AddYears(-1);
            dt = new DateTime(dt.Year, 1, 1);
            dt = dt.AddMonths(end);
            return dt;
        }

    }
}