using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using System.Text;
using System.Threading;

namespace Common.system
{
    /// <summary>
    /// HttpHelper
    /// 创建人：赵耀
    /// </summary>
    public class HttpHelper
    {
        public static void init_Request(ref System.Net.HttpWebRequest request)
        {
            request.Accept = "text/json,*/*;q=0.5";
            request.Headers.Add("Accept-Charset", "utf-8;q=0.7,*;q=0.7");
            request.Headers.Add("Accept-Encoding", "gzip, deflate, x-gzip, identity; q=0.9");
            request.AutomaticDecompression = System.Net.DecompressionMethods.GZip;
            request.Timeout = 8000;
        }

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

        public static System.Net.HttpWebRequest GetHttpWebRequest(string url)
        {
            HttpWebRequest request = null;
            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;
            }
            return request;
        }
        public static WebResponse Download(string downloadUrl, long from, long to, string method)
        {
            for (int i = 0; i < 10; i++)
            {
                try
                {
                    var request = HttpHelper.GetHttpWebRequest(downloadUrl);
                    HttpHelper.init_Request(ref request);
                    request.Accept = "text/json,*/*;q=0.5";
                    request.AddRange(from, to);
                    request.Headers.Add("Accept-Charset", "utf-8;q=0.7,*;q=0.7");
                    request.Headers.Add("Accept-Encoding", "gzip, deflate, x-gzip, identity; q=0.9");
                    request.AutomaticDecompression = System.Net.DecompressionMethods.GZip;
                    request.Timeout = 120000;
                    request.Method = method;
                    request.KeepAlive = false;
                    request.ContentType = "application/json; charset=utf-8";
                    return request.GetResponse();
                }
                catch (Exception)
                {
                    Thread.Sleep(100);
                }
            }
            throw new Exception("已断开网络！请检查网络连接后重试下载！");
        }
        public static string Get(string url, IDictionary<string, string> param)
        {
            var paramBuilder = new List<string>();
            foreach (var item in param)
            {
                paramBuilder.Add(string.Format("{0}={1}", item.Key, item.Value));
            }
            url = string.Format("{0}?{1}", url.TrimEnd('?'), string.Join(",", paramBuilder.ToArray()));
            return Get(url);
        }
        public static string Get(string url)
        {
            try
            {
                var request = GetHttpWebRequest(url);
                if (request != null)
                {
                    string retval = null;
                    init_Request(ref request);
                    using (var Response = request.GetResponse())
                    {
                        using (var reader = new System.IO.StreamReader(Response.GetResponseStream(), System.Text.Encoding.UTF8))
                        {
                            retval = reader.ReadToEnd();
                        }
                    }
                    return retval;
                }
            }
            catch
            {

            }
            return null;
        }
        public static string Post(string url, string data)
        {
            try
            {
                var request = GetHttpWebRequest(url);
                if (request != null)
                {
                    string retval = null;
                    init_Request(ref request);
                    request.Method = "POST";
                    request.ServicePoint.Expect100Continue = false;
                    request.ContentType = "application/json; charset=utf-8";
                    request.Timeout = 800;
                    var bytes = System.Text.UTF8Encoding.UTF8.GetBytes(data);
                    request.ContentLength = bytes.Length;
                    using (var stream = request.GetRequestStream())
                    {
                        stream.Write(bytes, 0, bytes.Length);
                    }
                    using (var response = request.GetResponse())
                    {
                        using (var reader = new System.IO.StreamReader(response.GetResponseStream()))
                        {
                            retval = reader.ReadToEnd();
                        }
                    }
                    return retval;
                }
            }
            catch
            {

            }
            return null;
        }
    }
}