using System;
using System.Security.Cryptography;
using System.Text;
using Hh.Mes.Common.log;

namespace Hh.Mes.Common
{
    public class Encryption
    {
        private static string encryptKey = "4h!@w$rng,i#$@x1%)5^3(7*5P31/Ee0";

        //默认密钥向量
        private static byte[] Keys = { 0x41, 0x72, 0x65, 0x79, 0x6F, 0x75, 0x6D, 0x79, 0x53, 0x6E, 0x6F, 0x77, 0x6D, 0x61, 0x6E, 0x3F };
        /// <summary>
        /// 加密
        /// </summary>
        /// <param name="encryptString"></param>
        /// <returns></returns>
        public static string Encrypt(string encryptString)
        {
            if (string.IsNullOrEmpty(encryptString))
                return string.Empty;
            Aes rijndaelProvider = Aes.Create();
            rijndaelProvider.Key = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 32));
            rijndaelProvider.IV = Keys;
            ICryptoTransform rijndaelEncrypt = rijndaelProvider.CreateEncryptor();

            byte[] inputData = Encoding.UTF8.GetBytes(encryptString);
            byte[] encryptedData = rijndaelEncrypt.TransformFinalBlock(inputData, 0, inputData.Length);

            return Convert.ToBase64String(encryptedData);
        }

        /// <summary>
        /// 解密
        /// </summary>
        /// <param name="decryptString"></param>
        /// <returns></returns>
        public static string Decrypt(string decryptString)
        {
            if (string.IsNullOrEmpty(decryptString))
                return string.Empty;
            try
            {
                Aes rijndaelProvider = Aes.Create();
                rijndaelProvider.Key = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 32));
                rijndaelProvider.IV = Keys;
                ICryptoTransform rijndaelDecrypt = rijndaelProvider.CreateDecryptor();

                byte[] inputData = Convert.FromBase64String(decryptString);
                byte[] decryptedData = rijndaelDecrypt.TransformFinalBlock(inputData, 0, inputData.Length);

                return Encoding.UTF8.GetString(decryptedData);
            }
            catch
            {
                return "";
            }
        }


        /// <summary>
        /// AES加密
        /// </summary>
        /// <param name="source"></param>
        /// <param name="key">密钥</param>
        /// <param name="iv">初始向量</param>
        /// <param name="padding">填充模式</param>
        /// <param name="mode">加密模式</param>
        /// <returns></returns>
        public static (bool isOk, string text) AESEncrypt(string source, string key, string iv = "", PaddingMode padding = PaddingMode.Zeros, CipherMode mode = CipherMode.CBC)
        {
            try
            {
                byte[] keyBytes = Encoding.UTF8.GetBytes(key);
                byte[] textBytes = Encoding.UTF8.GetBytes(source);
                byte[] ivBytes = Encoding.UTF8.GetBytes(iv);

                byte[] useKeyBytes = new byte[16];
                byte[] useIvBytes = new byte[16];

                Array.Copy(keyBytes, useKeyBytes, keyBytes.Length > useKeyBytes.Length ? useKeyBytes.Length : keyBytes.Length);

                Array.Copy(ivBytes, useIvBytes, ivBytes.Length > useIvBytes.Length ? useIvBytes.Length : ivBytes.Length);

                Aes aes = Aes.Create();
                aes.KeySize = 256;//秘钥的大小，以位为单位,128,256等
                aes.BlockSize = 128;//支持的块大小
                aes.Padding = padding;//填充模式
                aes.Mode = mode;
                aes.Key = useKeyBytes;
                aes.IV = useIvBytes;//初始化向量，如果没有设置默认的16个0

                ICryptoTransform cryptoTransform = aes.CreateEncryptor();
                byte[] resultBytes = cryptoTransform.TransformFinalBlock(textBytes, 0, textBytes.Length);

                return (true, Convert.ToBase64String(resultBytes));
            }
            catch (Exception ex)
            {
                return (false, ex.Message);
            }
        }

        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="source"></param>
        /// <param name="key">密钥</param>
        /// <param name="iv">初始向量</param>
        /// <param name="padding">填充模式</param>
        /// <param name="mode">加密模式</param>
        /// <returns></returns>
        public static (bool isOk, string text) AESDecrypt(string source, string key, string iv = "", PaddingMode padding = PaddingMode.Zeros, CipherMode mode = CipherMode.CBC)
        {
            try
            {
                byte[] textBytes = Convert.FromBase64String(source);
                byte[] keyBytes = Encoding.UTF8.GetBytes(key);
                byte[] ivBytes = Encoding.UTF8.GetBytes(iv);

                byte[] useKeyBytes = new byte[16];
                byte[] useIvBytes = new byte[16];

                Array.Copy(keyBytes, useKeyBytes, keyBytes.Length > useKeyBytes.Length ? useKeyBytes.Length : keyBytes.Length);

                Array.Copy(ivBytes, useIvBytes, ivBytes.Length > useIvBytes.Length ? useIvBytes.Length : ivBytes.Length);

                Aes aes = Aes.Create();
                aes.KeySize = 256;//秘钥的大小，以位为单位,128,256等
                aes.BlockSize = 128;//支持的块大小
                aes.Padding = padding;//填充模式
                aes.Mode = mode;
                aes.Key = useKeyBytes;
                aes.IV = useIvBytes;//初始化向量，如果没有设置默认的16个0

                ICryptoTransform decryptoTransform = aes.CreateDecryptor();
                byte[] resultBytes = decryptoTransform.TransformFinalBlock(textBytes, 0, textBytes.Length);

                return (true, Encoding.UTF8.GetString(resultBytes).Replace("\0", ""));
            }
            catch (Exception ex)
            {
                Log4NetHelper.Instance.Error("【AESDecrypt】" + ex.Message);
                return (false, ex.Message);
            }
        }

        //private static string ENCRY_ALGORITHM = "AES";
        //private static string CIPHER_MODE = "AES/ECB/PKCS5Padding";

        /// <summary>
        /// AES解密OA
        /// </summary>
        /// <param name="encryptStr"></param>
        /// <param name="decryptKey"></param>
        /// <returns></returns>
        public static string AesDecryptOA(string encryptStr, string decryptKey)
        {
            try
            {
                byte[] encryptByte = Convert.FromBase64String(encryptStr);
                using (Aes aes = Aes.Create())
                {
                    aes.Key = Encoding.UTF8.GetBytes(decryptKey);
                    aes.Mode = CipherMode.ECB;
                    aes.Padding = PaddingMode.PKCS7;

                    using (ICryptoTransform decryptor = aes.CreateDecryptor())
                    {
                        byte[] clearTextBytes = decryptor.TransformFinalBlock(encryptByte, 0, encryptByte.Length);
                        return Encoding.UTF8.GetString(clearTextBytes);
                    }
                }
            }
            catch (CryptographicException ex)
            {
                Log4NetHelper.Instance.Error("【AesDecryptOA】" + ex.Message);
            }
            catch (Exception ex)
            {
                Log4NetHelper.Instance.Error("【AesDecryptOA】" + ex.Message);
            }
            return null;
        }
    }
}