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

namespace Uni_Trend.MSO7000X.Common.Helper
{
    public static class SIHelper
    {
        private static string SICollection = "yzafpnμmDkMGTPEZY";
        /// <summary>
        /// 按SI单位制为数字添加后缀
        /// </summary>
        /// <param name="value">需要转换的数字</param>
        /// <param name="decimals">小数位数</param>
        /// <param name="unit">附加单位</param>
        /// <returns></returns>
        public static string ValueChangeToSI(double value, int decimals = 1, string unit = "", double hex = 1000, bool invalid = true)
        {
            if (hex <= 0) hex = 1000;
            if (double.IsNaN(value)) return "NaN";
            if (value == 0)
            {
                return value + unit;
            }
            if (Math.Abs(value) < 1E-24 || Math.Abs(value) > 1E24) return Math.Round((decimal)0f, decimals) + unit;
            string SI = SICollection;
            double d = Math.Log(Math.Abs(value), hex);
            decimal number = Math.Round((decimal)(value / Math.Pow(hex, Math.Floor(d))), decimals);
            d += 8;
            string s = SI.Substring((int)d, 1);
            if (s == "D") s = "";
            if (!invalid)
            {
                string formatstring = "#0";
                if (decimals > 0)
                {
                    formatstring += ".";
                    for (int i = 0; i < decimals; i++) formatstring += "#";
                }
                return number.ToString(formatstring) + s + unit;
            }
            else
            {
                string formatstr = "{0:N" + decimals + "}{1}{2}";
                return string.Format(formatstr, number, s, unit);
            }
        }
        public static string ValueChangeToSI(double value, out string siUnit, out string numberstring, int decimals = 1, string unit = "", bool invalid = false)
        {
            string formatstring = "#0";
            if (!invalid)
            {
                if (decimals > 0)
                {
                    formatstring += ".";
                    for (int i = 0; i < decimals; i++) formatstring += "#";
                }
            }
            else
            {
                formatstring = "N" + decimals;
            }
            siUnit = unit;
            if (double.IsNaN(value))
            {
                numberstring = "NaN";
                return "NaN";
            }
            if (value == 0)
            {
                numberstring = value.ToString(formatstring);
                return numberstring + unit;
            }
            if (Math.Abs(value) < 1E-24)
            {
                numberstring = Math.Round((decimal)0f, decimals) + "";
                return Math.Round((decimal)0f, decimals) + unit;
            }
            string SI = SICollection;
            double d = Math.Log(Math.Abs(value), 1000);
            decimal number = Math.Round((decimal)(value / Math.Pow(1000, Math.Floor(d))), decimals);
            d += 8;
            if (d > 16)
            {
                numberstring = "NaN";
                siUnit = "";
                return "";
            }
            string s = SI.Substring((int)d, 1);
            if (s == "D") s = "";
            siUnit = s + unit;
            numberstring = number.ToString(formatstring);
            return numberstring + siUnit;
        }
        public static double SIChangeToValue(string SI, string unit = "", double hex = 1000)
        {
            try
            {
                if (hex <= 0) hex = 1000;
                if (string.IsNullOrEmpty(SI)) return 0;
                string s = Regex.Replace(SI, unit + "$", "").Trim();
                string SIunit = s.Substring(s.Length - 1, 1);
                double Value = 0;
                if (int.TryParse(SIunit, out int Number))
                {
                    double.TryParse(s, out Value);
                }
                else
                {
                    string units = SICollection;
                    int index = units.IndexOf(SIunit) - 8;
                    double d = Math.Pow(hex, index);
                    double.TryParse(s.Substring(0, s.Length - 1), out Value);
                    Value *= d;
                }
                return Value;
            }
            catch { return 0; }
        }
        public static string FormatString(string str)
        {
            string[] s = str.Split('.');
            if (s.Length == 0) return str;
            string s0 = s[0];
            if (s0.Length > 3)
            {
                List<string> ss = new List<string>();
                ss.Add(s0.Substring(0, s0.Length - ((int)s0.Length / 3) * 3));
                s0 = s0.Substring(ss[0].Length);
                for (int i = 0; i < Math.Floor(s0.Length / 3f); i++)
                {
                    ss.Add(s0.Substring(i * 3, 3));
                }
                s0 = string.Join(" ", ss.ToArray()).Trim();
            }
            if (s.Length == 1) return s0;
            string s1 = s[1];
            if (s1.Length > 3)
            {
                List<string> ss = new List<string>();
                for (int i = 0; i < Math.Floor(s1.Length / 3f); i++)
                {
                    ss.Add(s1.Substring(i * 3, 3));
                }
                ss.Add(s1.Substring(((int)(s1.Length / 3)) * 3, s1.Length - ((int)(s1.Length / 3)) * 3));
                s1 = string.Join(" ", ss.ToArray()).Trim();
            }
            return string.Join(".", new string[] { s0, s1 });
        }
        /// <summary>
        /// SI单位的互相转换
        /// </summary>
        /// <param name="sourceValue"></param>
        /// <param name="sourceUnitIndex"></param>
        /// <param name="destUnitIndex"></param>
        /// <param name="hex"></param>
        /// <returns></returns>
        public static double SIUnitConversion(Double sourceValue, Int32 sourceUnitIndex, Int32 destUnitIndex, double hex = 1000)
        {
            if (hex <= 0) hex = 1000;
            Int32 index = sourceUnitIndex - destUnitIndex;
            return sourceValue * Math.Pow(hex, index);
        }
    }
}