using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Security.Cryptography;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;
using System.Web;
using System.Web.Http;

namespace QZWebApi.Bus
{
    public class TjSignUtil
    {
        //public static readonly string HospitalId = "6";
        //public static readonly string AESKey = "QpD3TQJNBsloXVNg9mmguc9ql5Y09Vb7";
        //public static readonly string AESJavaToNetKey = "tkvkfP3UFaV/AyJYnoLTCg==";

        public static long Get_Timestamp()
        {
            var currentTimeMillis = (long)(DateTime.UtcNow - new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc)).TotalMilliseconds;
            return currentTimeMillis / 1000L;
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="DecryptString"></param>
        /// <returns></returns>
        public static string GetSignature(string DecryptString)
        {
            SHA1CryptoServiceProvider sha1 = new SHA1CryptoServiceProvider();
            byte[] str1 = Encoding.UTF8.GetBytes(DecryptString);
            byte[] str2 = sha1.ComputeHash(str1);
            sha1.Clear();
            (sha1 as IDisposable).Dispose();

            return byteToHexStr(str2);
        }

        /// <summary>
        /// 字节数组转16进制字符串
        /// </summary>
        /// <param name="bytes"></param>
        /// <returns></returns>
        public static string byteToHexStr(byte[] bytes)
        {
            string returnStr = "";
            if (bytes != null)
            {
                for (int i = 0; i < bytes.Length; i++)
                {
                    returnStr += bytes[i].ToString("X2");
                }
            }
            return returnStr;
        }

        ///// <summary>
        ///// 无符号右移, 相当于java里的 value>>>pos
        ///// </summary>
        ///// <param name="value"></param>
        ///// <param name="pos"></param>
        ///// <returns></returns>
        //public static int RightMove(int value, int pos)
        //{
        //    //移动 0 位时直接返回原值
        //    if (pos != 0)
        //    {
        //        // int.MaxValue = 0x7FFFFFFF 整数最大值
        //        int mask = int.MaxValue;
        //        //无符号整数最高位不表示正负但操作数还是有符号的，有符号数右移1位，正数时高位补0，负数时高位补1
        //        value = value >> 1;
        //        //和整数最大值进行逻辑与运算，运算后的结果为忽略表示正负值的最高位
        //        value = value & mask;
        //        //逻辑运算后的值无符号，对无符号的值直接做右移运算，计算剩下的位
        //        value = value >> pos - 1;
        //    }

        //    return value;
        //}

        /** 
        * 生成验证签名 
        * @param timestamp 
        * @param openid 
        * @return signature 
        */
        public static string GetSignatureBytoken(string token, string timestamp, string openid)
        {
            string[] arr = new string[] { token, timestamp, openid };
            // 将token、timestamp、openid三个参数进行字典排序  
            //System.out.println("FF_token:"+WxParamUtil.getToken()+" time:"+timestamp+" id:"+openid);
            Array.Sort(arr);
            StringBuilder content = new StringBuilder();
            for (int i = 0; i < arr.Length; i++)
            {
                content.Append(arr[i]);
            }
            //MessageDigest md = null;
            string tmpStr = null;
            //System.out.println("FF_content:"+content.toString());
            try
            {
                //md = MessageDigest.getInstance("SHA-1");
                // 将三个参数字符串拼接成一个字符串进行sha1加密  

                tmpStr = GetSignature(content.ToString());
            }
            catch (Exception e)
            {
                //e.printStackTrace();
            }
            //System.out.println("FF_Signature:"+tmpStr);
            return tmpStr;
        }

        /// <summary>
        /// AES解密
        /// </summary>
        /// <param name="toDecrypt"></param>
        /// <param name="key"></param>
        /// <returns></returns>
        public static string Decrypt(string toDecrypt, string key)
        {
            toDecrypt = HexToBase64String(toDecrypt);
            byte[] keyArray = Convert.FromBase64String(key); //将TestGenAESByteKey类输出的字符串转为byte数组
            byte[] toEncryptArray = Convert.FromBase64String(toDecrypt);
            RijndaelManaged rDel = new RijndaelManaged();
            rDel.Key = keyArray;
            rDel.Mode = CipherMode.ECB;        //必须设置为ECB
            rDel.Padding = PaddingMode.PKCS7;  //必须设置为PKCS7
            ICryptoTransform cTransform = rDel.CreateDecryptor();
            byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
            return UTF8Encoding.UTF8.GetString(resultArray);
        }

        /// <summary>
        /// 16进制转Base64
        /// </summary>
        /// <param name="retrunValue"></param>
        /// <returns></returns>
        private static string HexToBase64String(string retrunValue)
        {
            MatchCollection mc = Regex.Matches(retrunValue.ToString(), "[A-F0-9]{2}"); byte[] bytes = new byte[mc.Count]; for (int i = 0; i < mc.Count; i++) { bytes[i] = byte.Parse(mc[i].Value, System.Globalization.NumberStyles.HexNumber); }
            return Convert.ToBase64String(bytes);
        }

        /// <summary>
        /// AES加密
        /// </summary>
        /// <param name="encryptString"></param>
        /// <param name="encryptKey"></param>
        /// <returns></returns>
        public static string AESEncode(string encryptString, string encryptKey)
        {
            if (string.IsNullOrEmpty(encryptString)) return null;
            Byte[] toEncryptArray = Encoding.UTF8.GetBytes(encryptString);
            RijndaelManaged rm = new RijndaelManaged
            {
                Key = Convert.FromBase64String(encryptKey),
                Mode = CipherMode.ECB,
                Padding = PaddingMode.PKCS7
            };
            ICryptoTransform cTransform = rm.CreateEncryptor();
            Byte[] resultArray = cTransform.TransformFinalBlock(toEncryptArray, 0, toEncryptArray.Length);
            //return Convert.ToBase64String(resultArray, 0, resultArray.Length);
            return byteToHexStr(resultArray);
        }
    }

    public class FileStreamResult : IHttpActionResult
    {
        readonly Stream _stream;
        readonly string _mediaType;
        readonly string _fileName;

        public FileStreamResult(Stream stream, string mediaType) : this(stream, mediaType, null) { }

        public FileStreamResult(Stream stream, string mediaType, string fileName)
        {
            _stream = stream;
            _mediaType = mediaType;
            _fileName = fileName;
        }

        public Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
        {
            return Task.FromResult<HttpResponseMessage>(Execute());
        }

        private HttpResponseMessage Execute()
        {
            HttpResponseMessage httpResponseMessage = new HttpResponseMessage(HttpStatusCode.OK);
            try
            {
                httpResponseMessage.Content = new StreamContent(_stream);
                httpResponseMessage.Content.Headers.ContentType = new MediaTypeHeaderValue(_mediaType);
                if (!string.IsNullOrEmpty(_fileName))
                {
                    httpResponseMessage.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
                    {
                        FileName = HttpUtility.UrlEncode(_fileName, Encoding.UTF8),
                    };
                }
                return httpResponseMessage;
            }
            catch
            {
                httpResponseMessage.Dispose();
                throw;
            }
        }
    }
}