using System;
using System.Configuration;
using System.Security.Cryptography;
using System.Text;

namespace HZQR.Common
{
    /// <summary>
    /// 商业集团会员系统相关方法
    /// </summary>
    public class ZJZCGCMemberHelper
    {
        #region 商业集团会员接口服务地址
        internal const string _ApiURL = "https://hywx.zcgc.cn/api/open/do";
        /// <summary>
        /// 商业集团会员接口服务地址
        /// </summary>
        public static string ApiURL
        {
            get
            {
                if (ConfigurationManager.AppSettings["ApiURL"] == null)
                {
                    return _ApiURL;
                }
                else
                {
                    return ConfigurationManager.AppSettings["ApiURL"];
                }

            }
        }
        #endregion

        #region 商业集团会员接口AppId
        internal const string _AppId = "AK202209070148347162";
        /// <summary>
        /// 商业集团会员接口AppId
        /// </summary>
        public static string AppId
        {
            get
            {
                if (ConfigurationManager.AppSettings["AppId"] == null)
                {
                    return _AppId;
                }
                else
                {
                    return ConfigurationManager.AppSettings["AppId"];
                }

            }
        }
        #endregion

        #region 商业集团会员接口AppSecret
        internal const string _AppSecret = "0ae62dc278de2ada91808ac501e81171";
        /// <summary>
        /// 商业集团会员接口AppSecret
        /// </summary>
        public static string AppSecret
        {
            get
            {
                if (ConfigurationManager.AppSettings["AppSecret"] == null)
                {
                    return _AppSecret;
                }
                else
                {
                    return ConfigurationManager.AppSettings["AppSecret"];
                }

            }
        }
        #endregion

        #region AES加密
        /// <summary>
        /// AES加密
        /// </summary>
        /// <param name="text">明文</param>
        /// <param name="key">密钥,长度为16的字符串</param>
        /// <param name="iv">偏移量,长度为16的字符串</param>
        /// <param name="isHex">
        /// <para>True：输出Hex格式密文</para>
        /// <para>False：输出Base64格式密文</para>
        /// </param>
        /// <returns>密文</returns>
        public static string AESEncrypt(string text, string key, string iv = "", bool isHex = false)
        {
            if (key.Length > 16)
            {
                key = key.Substring(0, 16);
            }
            //密码转换Byte数据
            byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
            //使用加密后的密钥对数据进行AES加密
            AesManaged rijndaelCipher = new AesManaged
            {
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7,
                KeySize = 128,
                BlockSize = 128,
                Key = pwdBytes
            };
            if (!string.IsNullOrWhiteSpace(iv))
            {
                byte[] ivBytes = Encoding.UTF8.GetBytes(iv);
                rijndaelCipher.IV = ivBytes;//需要IV的启用这两句
            }
            ICryptoTransform transform = rijndaelCipher.CreateEncryptor();
            byte[] plainText = Encoding.UTF8.GetBytes(text);
            byte[] cipherBytes = transform.TransformFinalBlock(plainText, 0, plainText.Length);
            if (isHex)
                return ToHex(cipherBytes);//输出为hex即启用此句，注释上一句
            else
                return Convert.ToBase64String(cipherBytes);//输出为Base64即启用此句，注释下一句
        }
        #endregion

        #region AES解密
        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="text">密文</param>
        /// <param name="key">密钥,长度为16的字符串</param>
        /// <param name="iv">偏移量,长度为16的字符串</param>
        /// <param name="isHex"> 
        /// <para>True：输入Hex格式密文</para>
        /// <para>False：输入Base64格式密文</para></param>
        /// <returns>明文</returns>
        public static string AESDecrypt(string text, string key, string iv = "", bool isHex = false)
        {
            if (key.Length > 16)
            {
                key = key.Substring(0, 16);
            }
            byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
            AesManaged rijndaelCipher = new AesManaged
            {
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7,
                KeySize = 128,
                BlockSize = 128,
                Key = pwdBytes
            };

            if (!string.IsNullOrWhiteSpace(iv))
            {
                byte[] ivBytes = Encoding.UTF8.GetBytes(iv);
                rijndaelCipher.IV = ivBytes;//需要IV的启用这两句
            }

            byte[] encryptedData;
            if (isHex)
                encryptedData = UnHex(text);//输出为hex即启用此句，注释上一句
            else
                encryptedData = Convert.FromBase64String(text);//输出为Base64即启用此句，注释下一句

            ICryptoTransform transform = rijndaelCipher.CreateDecryptor();
            byte[] plainText = transform.TransformFinalBlock(encryptedData, 0, encryptedData.Length);
            return Encoding.UTF8.GetString(plainText);
        }
        #endregion

        #region Hex与byte转码
        /// <summary>
        /// 从字符串转换到16进制表示的字符串
        /// </summary>
        /// <param name="bytes">需要转码的byte</param>
        /// <returns>返回结果</returns>
        private static string ToHex(byte[] bytes)
        {
            string str = string.Empty;
            if (bytes != null || bytes.Length > 0)
            {
                for (int i = 0; i < bytes.Length; i++)
                {
                    str += string.Format("{0:X2}", bytes[i]);
                }
            }
            return str.ToLower();
        }

        /// <summary>
        /// 从16进制转换成utf编码的字符串
        /// </summary>
        /// <param name="hex">需要转码的hex</param>
        /// <returns></returns>
        public static byte[] UnHex(string hex)
        {
            if (hex == null)
                throw new ArgumentNullException("hex");
            hex = hex.Replace(",", "");
            hex = hex.Replace("\n", "");
            hex = hex.Replace("\\", "");
            hex = hex.Replace(" ", "");
            if (hex.Length % 2 != 0)
            {
                hex += "20";//空格
                throw new ArgumentException("hex is not a valid number!", "hex");
            }
            // 需要将 hex 转换成 byte 数组。
            byte[] bytes = new byte[hex.Length / 2];
            for (int i = 0; i < bytes.Length; i++)
            {
                try
                {
                    // 每两个字符是一个 byte。
                    bytes[i] = byte.Parse(hex.Substring(i * 2, 2),
                    System.Globalization.NumberStyles.HexNumber);
                }
                catch
                {
                    // Rethrow an exception with custom message.
                    throw new ArgumentException("hex is not a valid hex number!", "hex");
                }
            }
            return bytes;
        }
        #endregion
    }
}