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

namespace StressClient.Common
{
    public class StrHexHelper
    {
        // 字符串转16进制字符串   AB-->4142
        public static string StrToHexStr(string str, Encoding encode)
        {
            byte[] b = encode.GetBytes(str);

            string result = string.Empty;
            foreach (var t in b)
            {
                result += Convert.ToString(t, 16);
            }
            return result;
        }

        // 将16进制字符串转换到byte[]
        public static byte[] HexStrToArray(string str)
        {
            int count = str.Length / 2;
            byte[] b = new byte[count];
            for (int i = 0; i < count; i++)
            {
                string val = "0x" + str.Substring(i * 2, 2);
                b[i] = Convert.ToByte(val, 16);    // '0x41'->65
            }
            return b;
        }

        public static string do_CRC(byte[] data)
        {
            uint crc = 0xFFFF;

            foreach (var pos in data)
            {
                crc = (crc >> 8) ^ pos;
                for (int i = 0; i < 8; i++)
                {
                    var check = (byte)(crc & 0x0001);
                    crc >>= 1;
                    if (check == 0x0001)
                        crc ^= 0xA001;
                }
            }

            //string ret_str = Convert.ToString(crc, 16);
            string ret_str = crc.ToString("X4"); ;
            return ret_str.ToUpper();
        }

        public static string do_CRC16(byte[] data)
        {
            byte[] returnVal = new byte[2];
            byte CRC16Lo, CRC16Hi, CL, CH, SaveHi, SaveLo;
            int i, Flag;
            CRC16Lo = 0xFF;
            CRC16Hi = 0xFF;
            CL = 0x86;
            CH = 0x68;
            for (i = 0; i < data.Length; i++)
            {
                CRC16Lo = (byte)(CRC16Lo ^ data[i]);//每一个数据与CRC寄存器进行异或
                for (Flag = 0; Flag <= 7; Flag++)
                {
                    SaveHi = CRC16Hi;
                    SaveLo = CRC16Lo;
                    CRC16Hi = (byte)(CRC16Hi >> 1);//高位右移一位
                    CRC16Lo = (byte)(CRC16Lo >> 1);//低位右移一位
                    if ((SaveHi & 0x01) == 0x01)//如果高位字节最后一位为
                    {
                        CRC16Lo = (byte)(CRC16Lo | 0x80);//则低位字节右移后前面补 否则自动补0
                    }
                    if ((SaveLo & 0x01) == 0x01)//如果LSB为1，则与多项式码进行异或
                    {
                        CRC16Hi = (byte)(CRC16Hi ^ CH);
                        CRC16Lo = (byte)(CRC16Lo ^ CL);
                    }
                }
            }
            returnVal[0] = CRC16Hi;//CRC高位
            returnVal[1] = CRC16Lo;//CRC低位
            return Encoding.UTF8.GetString(returnVal);
        }
    }

    public class Helper
    {
        public static decimal GetRan(int val, int diff, decimal k = 1)
        {
            if (k <= 0)
                return 0;
            System.Threading.Thread.Sleep(new Random().Next(10, 30));
            var ran = Convert.ToDecimal(new Random(DateTime.Now.Millisecond).Next(val - diff, val + diff)) / k;
            return ran;
        }
    }
}