using System;
using System.Collections.Generic;
using System.IO;
using BP.DA;
using System.Linq;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using System.Text;

namespace BP.WF
{
    public class HttpWebResponseUtility
    {
        private static readonly string DefaultUserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";
        /// <summary>  
        /// 创建GET方式的HTTP请求  
        /// </summary>  
        /// <param name="url">请求的URL</param>  
        /// <param name="timeout">请求的超时时间</param>  
        /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  
        /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>  
        /// <returns></returns>  
        public HttpWebResponse CreateGetHttpResponse(string url, int? timeout, string userAgent, CookieCollection cookies)
        {
            if (DataType.IsNullOrEmpty(url))
                throw new ArgumentNullException("url");

            HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
            //由于远程方已关闭传输流,身份验证失败  加这行
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11;
            request.Method = "GET";
            request.UserAgent = DefaultUserAgent;
            if (!DataType.IsNullOrEmpty(userAgent))
            {
                request.UserAgent = userAgent;
            }
            if (timeout.HasValue)
            {
                request.Timeout = timeout.Value;
            }
            if (cookies != null)
            {
                request.CookieContainer = new CookieContainer();
                request.CookieContainer.Add(cookies);
            }
            return request.GetResponse() as HttpWebResponse;
        }
        /// <summary>
        /// 创建POST方式的HTTP请求  
        /// </summary>  
        /// <param name="url">请求的URL</param>  
        /// <param name="parameters">随同请求POST的参数名称及参数值字典</param>  
        /// <param name="timeout">请求的超时时间</param>  
        /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  
        /// <param name="requestEncoding">发送HTTP请求时所用的编码</param>  
        /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>  
        /// <returns></returns>  
        public HttpWebResponse CreatePostHttpResponse(string url, IDictionary<string, string> parameters, int? timeout, string userAgent, Encoding requestEncoding, CookieCollection cookies)
        {
            if (DataType.IsNullOrEmpty(url))
            {
                throw new ArgumentNullException("url");
            }
            if (requestEncoding == null)
            {
                throw new ArgumentNullException("requestEncoding");
            }
            HttpWebRequest request = null;
            //如果是发送HTTPS请求  
            if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase))
            {
                ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);
                request = WebRequest.Create(url) as HttpWebRequest;
                request.ProtocolVersion = HttpVersion.Version10;
            }
            else
            {
                request = WebRequest.Create(url) as HttpWebRequest;
            }
            //由于远程方已关闭传输流,身份验证失败  加这行
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11;
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";

            if (!DataType.IsNullOrEmpty(userAgent))
            {
                request.UserAgent = userAgent;
            }
            else
            {
                request.UserAgent = DefaultUserAgent;
            }

            if (timeout.HasValue)
            {
                request.Timeout = timeout.Value;
            }
            if (cookies != null)
            {
                request.CookieContainer = new CookieContainer();
                request.CookieContainer.Add(cookies);
            }
            //如果需要POST数据  
            if (!(parameters == null || parameters.Count == 0))
            {
                StringBuilder buffer = new StringBuilder();
                int i = 0;
                foreach (string key in parameters.Keys)
                {
                    if (i > 0)
                    {
                        buffer.AppendFormat("&{0}={1}", key, parameters[key]);
                    }
                    else
                    {
                        buffer.AppendFormat("{0}={1}", key, parameters[key]);
                    }
                    i++;
                }
                byte[] data = requestEncoding.GetBytes(buffer.ToString());
                using (Stream stream = request.GetRequestStream())
                {
                    stream.Write(data, 0, data.Length);
                }
            }
            return request.GetResponse() as HttpWebResponse;
        }

        /// <summary>  
        /// 创建POST方式的HTTP请求 ContentType json 
        /// </summary>  
        /// <param name="url">请求的URL</param>  
        /// <param name="JsonParameters">随同请求POST的参数名称及参数值字典json</param>  
        /// <param name="timeout">请求的超时时间</param>  
        /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  
        /// <param name="requestEncoding">发送HTTP请求时所用的编码</param>  
        /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>  
        /// <returns></returns>  
        public HttpWebResponse CreatePostHttpResponse(string url, string JsonParameters, int? timeout, string userAgent, Encoding requestEncoding, CookieCollection cookies)
        {
            if (DataType.IsNullOrEmpty(url))
            {
                throw new ArgumentNullException("url");
            }
            if (requestEncoding == null)
            {
                throw new ArgumentNullException("requestEncoding");
            }
            HttpWebRequest request = null;
            //如果是发送HTTPS请求  
            if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase))
            {
                ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);
                request = WebRequest.Create(url) as HttpWebRequest;
                request.ProtocolVersion = HttpVersion.Version10;
            }
            else
            {
                request = WebRequest.Create(url) as HttpWebRequest;
            }
            request.Method = "POST";
            request.ContentType = "application/json";

            if (!DataType.IsNullOrEmpty(userAgent))
            {
                request.UserAgent = userAgent;
            }
            else
            {
                request.UserAgent = DefaultUserAgent;
            }

            if (timeout.HasValue)
            {
                request.Timeout = timeout.Value;
            }
            if (cookies != null)
            {
                request.CookieContainer = new CookieContainer();
                request.CookieContainer.Add(cookies);
            }
            //如果需要POST数据  
            if (!DataType.IsNullOrEmpty(JsonParameters))
            {
                byte[] data = requestEncoding.GetBytes(JsonParameters);
                using (Stream stream = request.GetRequestStream())
                {
                    stream.Write(data, 0, data.Length);
                }
            }
            return request.GetResponse() as HttpWebResponse;
        }
        /// <summary>  
        /// 创建POST方式的HTTP请求  (用于微信自动推送)
        /// </summary>  
        /// <param name="url">请求的URL</param>  
        /// <param name="parameters">随同请求POST的参数名称及参数值字典</param>  
        /// <param name="timeout">请求的超时时间</param>  
        /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  
        /// <param name="requestEncoding">发送HTTP请求时所用的编码</param>  
        /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>  
        /// <returns></returns>  
        public HttpWebResponse WXCreateGetHttpResponse(string url, StringBuilder parameters,
          int? timeout, string userAgent, Encoding requestEncoding, CookieCollection cookies)
        {
            if (DataType.IsNullOrEmpty(url))
                throw new Exception("err@url不能为空");
            if (requestEncoding == null)
                throw new Exception("err@requestEncoding，不能为空.");

            HttpWebRequest request = null;

            //如果是发送HTTPS请求  
            if (url.StartsWith("https", StringComparison.OrdinalIgnoreCase))
            {
                ServicePointManager.ServerCertificateValidationCallback =
                    new RemoteCertificateValidationCallback(CheckValidationResult);
                request = WebRequest.Create(url) as HttpWebRequest;
                request.ProtocolVersion = HttpVersion.Version10;
            }
            else
            {
                request = WebRequest.Create(url) as HttpWebRequest;
            }
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";

            if (DataType.IsNullOrEmpty(userAgent)==false)
            {
                request.UserAgent = userAgent;
            }
            else
            {
                request.UserAgent = DefaultUserAgent;
            }

            if (timeout.HasValue)
            {
                request.Timeout = timeout.Value;
            }
            if (cookies != null)
            {
                request.CookieContainer = new CookieContainer();
                request.CookieContainer.Add(cookies);
            }

            ///增加参数的地方.
            if (parameters != null)
            {
                StringBuilder sb = parameters;
                byte[] requestBytes = Encoding.UTF8.GetBytes(sb.ToString());
                request.ContentLength = requestBytes.Length;
                Stream requeStream = request.GetRequestStream();
                requeStream.Write(requestBytes, 0, requestBytes.Length);
                requeStream.Close();
            }
            return request.GetResponse() as HttpWebResponse;
        }

        private bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
        {
            return true; //总是接受  
        }

        /// <summary>
        /// 根据Url获取返回内容
        /// </summary>
        /// <param name="url"></param>
        /// <returns></returns>
        public string HttpResponseGet(string url)
        {
            HttpWebResponse response = this.CreateGetHttpResponse(url, 600000, null, null);
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
            string str = reader.ReadToEnd();
            reader.Dispose();
            reader.Close();
            if (response != null)
                response.Close();

            return str;
        }
        /// <summary>
        /// 随同请求POST的参数名称及参数值字典
        /// </summary>
        /// <param name="url">请求地址</param>
        /// <param name="parameters">参数集合</param>
        /// <returns>响应返回结果</returns>
        public string HttpResponsePost(string url, IDictionary<string, string> parameters)
        {
            Encoding encoding = Encoding.GetEncoding("utf-8");
            HttpWebResponse response = this.CreatePostHttpResponse(url, parameters, 10000, null, encoding, null);
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
            string str = reader.ReadToEnd();
            reader.Dispose();
            reader.Close();
            if (response != null)
                response.Close();

            return str;
        }
        /// <summary>
        /// 随同请求POST的参数名称及参数值字典
        /// </summary>
        /// <param name="url">请求地址</param>
        /// <param name="parameters">参数集合</param>
        /// <returns>响应返回结果</returns>
        public string HttpResponsePost_Json(string url, string parameters)
        {
            Encoding encoding = Encoding.GetEncoding("utf-8");
            HttpWebResponse response = this.CreatePostHttpResponse(url, parameters, 10000, null, encoding, null);
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
            string str = reader.ReadToEnd();
            reader.Dispose();
            reader.Close();
            if (response != null)
                response.Close();

            return str;
        }
    }
}