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

namespace HT.Cloud.Code
{
	public static class AESKeyEncrypt
	{
		#region 加解密方法二(Sha256和Sha512)
		/// <summary>
		/// Creates a SHA256 hash of the specified input.
		/// </summary>
		/// <param name="input">The input.</param>
		/// <returns>A hash</returns>
		public static string Sha256(this string input)
		{
			if (String.IsNullOrEmpty(input)) return string.Empty;
			using (var sha = SHA256.Create())
			{
				var bytes = Encoding.UTF8.GetBytes(input);
				var hash = sha.ComputeHash(bytes);
				return Convert.ToBase64String(hash);
			}
		}
		/// <summary>
		/// Creates a SHA256 hash of the specified input.
		/// </summary>
		/// <param name="input">The input.</param>
		/// <returns>A hash.</returns>
		public static byte[] Sha256(this byte[] input)
		{
			if (input == null)
			{
				return null;
			}
			using (var sha = SHA256.Create())
			{
				return sha.ComputeHash(input);
			}
		}
		/// <summary>
		/// Creates a SHA512 hash of the specified input.
		/// </summary>
		/// <param name="input">The input.</param>
		/// <returns>A hash</returns>
		public static string Sha512(this string input)
		{
			if (string.IsNullOrEmpty(input)) return string.Empty;
			using (var sha = SHA512.Create())
			{
				var bytes = Encoding.UTF8.GetBytes(input);
				var hash = sha.ComputeHash(bytes);
				return Convert.ToBase64String(hash);
			}
		}
		#endregion

		#region 加密解密法一
		//默认密钥向量 
		private static byte[] Keys = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F };

		/// <summary> 
		/// DES加密字符串 
		/// </summary> 
		/// <param name="encryptString">待加密的字符串</param> 
		/// <param name="encryptKey">加密密钥,要求为16位</param> 
		/// <returns>加密成功返回加密后的字符串，失败返回源串</returns> 

		public static string EncryptDES(string encryptString, string encryptKey = "HT87688588DB3037")
		{
			try
			{
				byte[] rgbKey = Encoding.UTF8.GetBytes(encryptKey.Substring(0, 16));
				byte[] rgbIV = Keys;
				byte[] inputByteArray = Encoding.UTF8.GetBytes(encryptString);
				var DCSP = Aes.Create();
				MemoryStream mStream = new MemoryStream();
				CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateEncryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
				cStream.Write(inputByteArray, 0, inputByteArray.Length);
				cStream.FlushFinalBlock();
				return Convert.ToBase64String(mStream.ToArray());
			}
			catch (Exception ex)
			{
				return ex.Message + encryptString;
			}

		}

		/// <summary> 
		/// DES解密字符串 
		/// </summary> 
		/// <param name="decryptString">待解密的字符串</param> 
		/// <param name="decryptKey">解密密钥,要求为16位,和加密密钥相同</param> 
		/// <returns>解密成功返回解密后的字符串，失败返源串</returns> 

		public static string DecryptDES(string decryptString, string decryptKey = "HT87688588DB3037")
		{
			try
			{
				byte[] rgbKey = Encoding.UTF8.GetBytes(decryptKey.Substring(0, 16));
				byte[] rgbIV = Keys;
				byte[] inputByteArray = Convert.FromBase64String(decryptString);
				var DCSP = Aes.Create();
				MemoryStream mStream = new MemoryStream();
				CryptoStream cStream = new CryptoStream(mStream, DCSP.CreateDecryptor(rgbKey, rgbIV), CryptoStreamMode.Write);
				Byte[] inputByteArrays = new byte[inputByteArray.Length];
				cStream.Write(inputByteArray, 0, inputByteArray.Length);
				cStream.FlushFinalBlock();
				return Encoding.UTF8.GetString(mStream.ToArray());
			}
			catch (Exception ex)
			{
				return ex.Message + decryptString;
			}

		}
		#endregion
	}
}