using MathNet.Numerics.Random;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace New_College.Common
{
    /// <summary>
    /// aes解密
    /// </summary>
    public static class RSAHelper
    {
        /// <summary>
        ///aes解密
        /// </summary>
        /// <param name="text"></param>
        /// <param name="AesKey"></param>
        /// <param name="AesIV"></param>
        /// <returns></returns>
        public static string AESDecrypt(string text, string AesKey, string AesIV)
        {
            try
            {

                //判断是否是16位 如果不够补0
                //text = tests(text);
                //16进制数据转换成byte
                byte[] encryptedData = Convert.FromBase64String(text);  // strToToHexByte(text);
                RijndaelManaged rijndaelCipher = new RijndaelManaged();
                rijndaelCipher.Key = Convert.FromBase64String(AesKey); // Encoding.UTF8.GetBytes(AesKey);
                rijndaelCipher.IV = Convert.FromBase64String(AesIV);// Encoding.UTF8.GetBytes(AesIV);
                rijndaelCipher.Mode = CipherMode.CBC;
                rijndaelCipher.Padding = PaddingMode.PKCS7;
                ICryptoTransform transform = rijndaelCipher.CreateDecryptor();
                byte[] plainText = transform.TransformFinalBlock(encryptedData, 0, encryptedData.Length);
                string result = Encoding.Default.GetString(plainText);
                //int index = result.LastIndexOf('>');
                //result = result.Remove(index + 1);
                return result;
            }
            catch (Exception ex)
            {
                return null;

            }
        }



        /// <summary>
        ///获取随机数
        /// </summary>
        /// <returns></returns>
        public static string GetRandomStr()
        {
            const string baseChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
            Random random = new Random();
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < 16; i++)
            {
                int index = random.Next(baseChars.Length);
                sb.Append(baseChars[index]);
            }
            return sb.ToString();
        }

    }
}