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

namespace Api.Framework.Tools
{
    public class AesHelper
    {
        /// <summary>
        /// 有密码的AES加密 
        /// </summary>
        /// <param name="text">加密字符</param>
        /// <param name="password">加密的密码</param>
        /// <returns></returns>
        public static string Encrypt(string toEncrypt, string key)
        {
            if (key.Length > 32)
            {
                key = key.Substring(0, 32);
            }
            try
            {
                byte[] keyArray = Encoding.UTF8.GetBytes(key);
                byte[] toEncryptArray = Encoding.UTF8.GetBytes(toEncrypt);
                RijndaelManaged rDel = new RijndaelManaged();
                rDel.Key = keyArray;
                rDel.Mode = CipherMode.ECB;
                rDel.Padding = PaddingMode.PKCS7;
                ICryptoTransform cTransform = rDel.CreateEncryptor();
                byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
                return ByteArrayToHexString(resultArray);
            }
            catch (Exception)
            {
                return "";
            }
        }

        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="text"></param>
        /// <param name="password"></param>
        /// <returns></returns>
        public static string Decrypt(string toDecrypt, string key)
        {
            if (key.Length > 32)
            {
                key = key.Substring(0, 32);
            }
            byte[] keyArray = Encoding.UTF8.GetBytes(key);
            byte[] toEncryptArray = Convert.FromBase64String(toDecrypt);
            RijndaelManaged rDel = new RijndaelManaged();
            rDel.Key = keyArray;
            rDel.Mode = CipherMode.ECB;
            rDel.Padding = PaddingMode.PKCS7;
            ICryptoTransform cTransform = rDel.CreateDecryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
            return Encoding.UTF8.GetString(resultArray);
        }
        /// <summary>
        /// 将一个byte数组转换成16进制字符串
        /// </summary>
        /// <param name="data"></param>
        /// <returns></returns>
        public static string ByteArrayToHexString(byte[] data)
        {
            StringBuilder sb = new StringBuilder(data.Length * 3);
            foreach (byte b in data)
            {
                sb.Append(Convert.ToString(b, 16).PadLeft(2, '0'));
            }
            return sb.ToString().ToUpper();
        }
        /// <summary>
        /// 将16进制字符串转换成byte数组
        /// </summary>
        /// <param name="hexString"></param>
        /// <returns></returns>
        public static byte[] ByteArrayToHexString(string hexString)
        {
            //将16进制秘钥转成字节数组
            var byteArray = new byte[hexString.Length / 2];
            for (var x = 0; x < byteArray.Length; x++)
            {
                var i = Convert.ToInt32(hexString.Substring(x * 2, 2), 16);
                byteArray[x] = (byte)i;
            }
            return byteArray;
        }
    }
}