using System;
using System.Collections.Generic;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
namespace TEAMModelOS.SDK
{
    public class AESHelper
    {
        public static string Decryptor(string TextToDecrypt,string strKey,string strIV)
        {
            byte[] EncryptedBytes = Convert.FromBase64String(TextToDecrypt);

            //Setup the AES provider for decrypting.
            Aes aesProvider = Aes.Create();
            //aesProvider.Key = System.Text.Encoding.ASCII.GetBytes(strKey);
            //aesProvider.IV = System.Text.Encoding.ASCII.GetBytes(strIV);
            aesProvider.BlockSize = 128;
            aesProvider.KeySize = 256;
            //My key and iv that i have used in openssl
            aesProvider.Key = System.Text.Encoding.UTF8.GetBytes(strKey);
            aesProvider.IV = System.Text.Encoding.UTF8.GetBytes(strIV);
            aesProvider.Padding = PaddingMode.PKCS7;
            aesProvider.Mode = CipherMode.CBC;


            ICryptoTransform cryptoTransform = aesProvider.CreateDecryptor(aesProvider.Key, aesProvider.IV);
            byte[] DecryptedBytes = cryptoTransform.TransformFinalBlock(EncryptedBytes, 0, EncryptedBytes.Length);
            return System.Text.Encoding.UTF8.GetString(DecryptedBytes);
        }
        public static string Encryptor(string TextToEncrypt, string strKey, string strIV)
        {
            //Turn the plaintext into a byte array.
            byte[] PlainTextBytes = System.Text.ASCIIEncoding.UTF8.GetBytes(TextToEncrypt);

            //Setup the AES providor for our purposes.
            Aes aesProvider = Aes.Create();

            aesProvider.BlockSize = 128;
            aesProvider.KeySize = 256;
            //My key and iv that i have used in openssl
            aesProvider.Key = System.Text.Encoding.UTF8.GetBytes(strKey);
            aesProvider.IV = System.Text.Encoding.UTF8.GetBytes(strIV);
            aesProvider.Padding = PaddingMode.PKCS7;
            aesProvider.Mode = CipherMode.CBC;

            ICryptoTransform cryptoTransform = aesProvider.CreateEncryptor(aesProvider.Key, aesProvider.IV);
            byte[] EncryptedBytes = cryptoTransform.TransformFinalBlock(PlainTextBytes, 0, PlainTextBytes.Length);
            return Convert.ToBase64String(EncryptedBytes);
        }



        /// <summary>
        /// 有密码的加密 
        /// </summary>
        /// <param name="toEncrypt">加密字符</param>
        /// <param name="key">加密的密码</param>
        /// <returns></returns>
        public static string AESEncrypt(string toEncrypt, string key)
        {
            byte[] keyArray = hexStringTobyte(key);
            byte[] toEncryptArray = UTF8Encoding.UTF8.GetBytes(toEncrypt);
            RijndaelManaged rDel = new RijndaelManaged();
            rDel.KeySize = 128;
            rDel.BlockSize = 128;
            rDel.Key = keyArray;
            rDel.Mode = CipherMode.ECB;
            rDel.Padding = PaddingMode.PKCS7;
            ICryptoTransform cTransform = rDel.CreateEncryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
            return byteToHexString(resultArray);
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="toDecrypt">解密字符</param>
        /// <param name="key">加密的密码</param>
        /// <returns></returns>
        public static string AESDecrypt(string toDecrypt, string key)
        {
            if (string.IsNullOrWhiteSpace(toDecrypt))
            {
                return "";
            }
            else {

                byte[] keyArray = hexStringTobyte(key);
                byte[] dest = hexStringTobyte(toDecrypt);
                RijndaelManaged rDel = new();
                rDel.KeySize = 128;
                rDel.BlockSize = 128;
                rDel.Key = keyArray;
                rDel.Mode = CipherMode.ECB;
                rDel.Padding = PaddingMode.PKCS7;
                ICryptoTransform cTransform = rDel.CreateDecryptor();
                try
                {
                    byte[] resultArray = cTransform.TransformFinalBlock(dest, 0, dest.Length);
                    return UTF8Encoding.UTF8.GetString(resultArray);
                }
                catch (Exception ex)
                {
                    return toDecrypt;

                }
            }   
        }


        private static byte[] hexStringTobyte(String s)
        {
            if (string.IsNullOrEmpty(s)) return null;
            s = s.ToLower();
            int byteArrayLength = s.Length / 2;
            byte[] b = new byte[byteArrayLength];
            for (int i = 0; i < byteArrayLength; i++)
            {
                byte b0 = Convert.ToByte(s.Substring(i * 2, 2), 16);
                b[i] = b0;
            }
            return b;
        }

        public static string byteToHexString(byte[] t)
        {
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < t.Length; i++)
            {
                sb.Append(t[i].ToString("x").PadLeft(2, '0'));
            }
            return sb.ToString().ToUpper();
        }
    }
}