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

namespace Container.Common
{
	/// <summary>
	/// 加密解密类
	/// </summary>
	public class SecurityHelper
	{
		#region AES加密解密 
		private static App app = ((App)System.Windows.Application.Current);
		/// <summary>
		/// 128位处理key 
		/// </summary>
		/// <param name="keyArray">原字节</param>
		/// <param name="key">处理key</param>
		/// <returns></returns>
		private static byte[] GetAesKey(byte[] keyArray, string key)
		{
			byte[] newArray = new byte[16];
			if (keyArray.Length < 16)
			{
				for (int i = 0; i < newArray.Length; i++)
				{
					if (i >= keyArray.Length)
					{
						newArray[i] = 0;
					}
					else
					{
						newArray[i] = keyArray[i];
					}
				}
			}
			else
				newArray = keyArray;

			return newArray;
		}
		/// <summary>
		/// 使用AES加密字符串,按128位处理key
		/// </summary>
		/// <param name="content">加密内容</param>
		/// <param name="key">秘钥，需要128位、256位.....</param>
		/// <returns>Base64字符串结果</returns>
		public static string AesEncrypt(string content, bool autoHandle = true)
		{
			byte[] keyArray = Encoding.UTF8.GetBytes(app.SecurityKey);
			if (autoHandle)
			{
				keyArray = GetAesKey(keyArray, app.SecurityKey);
			}
			byte[] toEncryptArray = Encoding.UTF8.GetBytes(content);

			SymmetricAlgorithm des = Aes.Create();
			des.Key = keyArray;
			des.Mode = CipherMode.ECB;
			des.Padding = PaddingMode.PKCS7;
			ICryptoTransform cTransform = des.CreateEncryptor();
			byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
			return Convert.ToBase64String(resultArray);
		}
		/// <summary>
		/// 使用AES解密字符串,按128位处理key
		/// </summary>
		/// <param name="content">内容</param>
		/// <param name="key">秘钥，需要128位、256位.....</param>
		/// <returns>UTF8解密结果</returns>
		public static string AesDecrypt(string content, bool autoHandle = true)
		{
			byte[] keyArray = Encoding.UTF8.GetBytes(app.SecurityKey);
			if (autoHandle)
			{
				keyArray = GetAesKey(keyArray, app.SecurityKey);
			}
			byte[] toEncryptArray = Convert.FromBase64String(content);

			SymmetricAlgorithm des = Aes.Create();
			des.Key = keyArray;
			des.Mode = CipherMode.ECB;
			des.Padding = PaddingMode.PKCS7;

			ICryptoTransform cTransform = des.CreateDecryptor();
			byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);

			return Encoding.UTF8.GetString(resultArray);
		}
		#endregion
	}
}