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

namespace PdmSwPlugin.Common.Util
{
    /// <summary>
    /// 字符加解密
    /// </summary>
    public class Encryptor
    {
        private readonly byte[] key;
        private readonly byte[] iv;

        public Encryptor(string keyString, string ivString)
        {
            key = Encoding.UTF8.GetBytes(keyString);
            iv = Encoding.UTF8.GetBytes(ivString);
        }

        public string Encrypt(string plainText)
        {
            using (var aes = Aes.Create())
            {
                aes.Key = key;
                aes.IV = iv;
                ICryptoTransform encryptor = aes.CreateEncryptor(aes.Key, aes.IV);

                using (MemoryStream msEncrypt = new MemoryStream())
                {
                    using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
                    {
                        using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
                        {
                            swEncrypt.Write(plainText);
                        }
                        return Convert.ToBase64String(msEncrypt.ToArray());
                    }
                }
            }
        }


        public string Decrypt(string cipherText)
        {
            using (var aes = Aes.Create())
            {
                aes.Key = key;
                aes.IV = iv;
                ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
                byte[] arr = Convert.FromBase64String(cipherText);
                using (MemoryStream msDecrypt = new MemoryStream(arr))
                {
                    using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
                    {
                        using (StreamReader srDecrypt = new StreamReader(csDecrypt))
                        {
                            return srDecrypt.ReadToEnd();
                        }
                    }
                }
            }
        }
    }
}