using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using System.Text;
using System.Web;

namespace QZWebApi.Bus
{
    public class HttpHelper
    {
        /// <summary>  
            /// 创建GET方式的HTTP请求  
            /// </summary>  
            /// <param name="url">请求的URL</param>   
            /// <param name="parameters">随同请求GET的参数名称及参数值字典</param>  
            /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>  
            /// <param name="timeout">请求的超时时间</param>  
            /// <returns></returns>  
        public static string CreateGetHttpRequest(string url, NameValueCollection parameters, string userAgent = "", int timeout = 90000)
        {
            if (string.IsNullOrEmpty(url))
            {
                throw new ArgumentNullException("url");
            }
            if (parameters != null && parameters.Count > 0)
            {
                if (url.Contains("?"))
                {

                    url = $"{url}&{NameValueCollectionToString(parameters)}";

                }
                else
                {
                    url = $"{url}?{NameValueCollectionToString(parameters)}";
                }
            }
            HttpWebRequest wreq = (HttpWebRequest)WebRequest.Create(url);
            wreq.Method = "GET";
            wreq.Timeout = timeout;
            wreq.UserAgent = (string.IsNullOrEmpty(userAgent)) ? "Mozilla/5.0 (Windows; U; Windows NT 6.1; zh-CN; rv:1.9.2.8) Gecko/20100722 Firefox/3.6.8" : userAgent;
            HttpWebResponse wresp = (HttpWebResponse)wreq.GetResponse();
            //采用流读取，并确定编码方式
            var result = "";
            using (HttpWebResponse httpWebResponse = wreq.GetResponse() as HttpWebResponse)
            {
                using (Stream stream2 = wreq.GetResponse().GetResponseStream())
                {
                    using (StreamReader streamReader = new StreamReader(stream2, Encoding.UTF8))
                    {
                        result = streamReader.ReadToEnd();

                    }
                }
            }
            return result;
        }

        public static string NameValueCollectionToString(NameValueCollection nvc)
        {
            StringBuilder sb = new StringBuilder();
            foreach (string key in nvc.Keys)
            {
                sb.AppendFormat("{0}={1}&", key, nvc[key]);
            }
            return sb.ToString().TrimEnd('&');
        }

        /// <summary> 
        /// 调用api返回json  
        /// </summary>  
        /// <param name="url">api地址</param>  
        /// <param name="jsonstr">接收参数</param>  
        /// <param name="type">类型</param>  
        /// <returns></returns>  
        public static string HttpPost(string url, string jsonstr)//,string type
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url + jsonstr); //--需要封装的参数
            request.CookieContainer = new CookieContainer();
            //以下是发送的http头
            request.Referer = "";
            //request.ContentType = "text/xml";
            request.Headers["Accept-Language"] = "zh-CN,zh;q=0.";
            request.Headers["Accept-Charset"] = "GBK,utf-8;q=0.7,*;q=0.3";
            request.UserAgent = "User-Agent:Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/14.0.835.202 Safari/535.1";
            request.KeepAlive = true;
            //上面的http头看情况而定，但是下面俩必须加 
            request.ContentType = "application/x-www-form-urlencoded";
            Encoding encoding = Encoding.UTF8;//根据网站的编码自定义
            request.Method = "get";  //--需要将get改为post才可行
            string postDataStr;
            //Stream requestStream = request.GetRequestStream();
            if (jsonstr != "")
            {
                postDataStr = jsonstr;//--需要封装,形式如“arg=arg1&arg2=arg2”
                byte[] postData = encoding.GetBytes(postDataStr);//postDataStr即为发送的数据，
                                                                 //request.ContentLength = postData.Length;  //写入后不允许设置此属性
                                                                 //requestStream.Write(postData, 0, postData.Length);
            }
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();  //远程服务器返回错误: (405) 不允许的方法/远程服务器返回错误: (500) 内部服务器错误。
            Stream responseStream = response.GetResponseStream();

            StreamReader streamReader = new StreamReader(responseStream, encoding);
            string retString = streamReader.ReadToEnd();

            streamReader.Close();
            responseStream.Close();
            return retString;

        }
    }
}