using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace X3TaskServer54
{
    static class SlotHelper
    {
        #region cpp dll Interop 
        private const string slotDll = @"AddIns\时隙获取\SlotChecker.dll";

        [DllImport(slotDll, EntryPoint = "getslots", CallingConvention = CallingConvention.Cdecl)]
        private extern static int GetFileSlots(string file, byte[] fileTime, ref float frequenceM, ref float fsampleM,
            ref int multi, ref int slotscount, out IntPtr slotst, out IntPtr slotle);

        [DllImport(slotDll, EntryPoint = "freeslots", CallingConvention = CallingConvention.Cdecl)]
        private extern static void Free(IntPtr slotst, IntPtr slotle);
        #endregion

        public static SlotsInfo GetFileSlots(string file)
        {
            SlotsInfo res = new SlotsInfo();
            string name = Path.GetFileName(file);
            res.FreqDownMHz = Convert.ToDouble(name.Split(new string[] { "_", "MHz" }, StringSplitOptions.RemoveEmptyEntries)[1]);
            byte[] timeData = new byte[6];
            float frequenceM = 0, fsampleM = 0;
            int multi = 0, slotscount = 0;
            IntPtr slotst, slotle;
            var ret = GetFileSlots(file, timeData, ref frequenceM, ref fsampleM, ref multi, ref slotscount, out slotst, out slotle);
            if (ret == 0)
            {
                res.FrequenceM = (float)((long)((decimal)frequenceM * 1000000) / 1e6);
                res.FsampleM = fsampleM;
                res.Multi = multi;
                res.AdTime = new DateTime(2000 + timeData[0], timeData[1], timeData[2], timeData[3], timeData[4], timeData[5]);
                float[] startsF = new float[slotscount];
                float[] lenF = new float[slotscount];
                Marshal.Copy(slotst, startsF, 0, slotscount);
                Marshal.Copy(slotle, lenF, 0, slotscount);
                for (int i = 0; i < slotscount; i++)
                {
                    Slot s = new Slot()
                    {
                        StartPoint = (int)(fsampleM * 1e6 / multi * startsF[i]),
                        Len = (int)(fsampleM * 1e6 / multi * lenF[i] * 1e-3)
                    };
                    res.Slots.Add(s);
                }
            }
            Free(slotst, slotle);
            return res;
        }
    }
    /// <summary>
    /// 突发信息
    /// </summary>
    class SlotsInfo
    {
        /// <summary>
        /// 采集时刻
        /// </summary>
        public DateTime AdTime { get; set; }

        /// <summary>
        /// 信号下行频点MHz
        /// </summary>
        public double FreqDownMHz { get; set; }

        /// <summary>
        /// AD采样率
        /// </summary>
        public float FsampleM { get; set; }

        /// <summary>
        /// 信号下行频点
        /// </summary>
        public float FrequenceM { get; set; }

        /// <summary>
        /// 抽取倍数
        /// </summary>
        public float Multi { get; set; }

        /// <summary>
        /// 时隙位置集合
        /// </summary>
        public List<Slot> Slots { get; set; } = new List<Slot>();
    }

    /// <summary>
    /// 时隙信息
    /// </summary>
    class Slot
    {
        /// <summary>
        /// 起始样点
        /// </summary>
        public int StartPoint { get; set; }

        /// <summary>
        /// 结束样点
        /// </summary>
        public int Len { get; set; }
    }
}