using System;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;
using System.Text;
using System.Threading.Tasks;
using System.Web;

namespace EShang.Common
{
    /// <summary>
    /// 通用的HTTP请求类
    /// </summary>
    public class HttpUtil
    {
        #region 方法 -> HTTP报文请求【POST】
        /// <summary>
        /// HTTP报文请求【POST】
        /// </summary>
        /// <param name="postDataStr">请求参数</param>
        /// <param name="RequestUrl">请求url</param>
        /// <param name="ContentType">资源的媒体类型，默认application/x-www-form-urlencoded</param>
        /// <param name="timeout">超时时间（TCP连接建立的时间和整个请求完成的时间超出了设置的时间，就抛出异常，程序中断）</param>
        /// <param name="securityProtocol">服务器通信的默认安全协议（众马对账通信需使用Tls12,WCF默认通道即可）</param>
        /// <returns></returns>
        public static string HttpUrlPost(string postDataStr, string RequestUrl, string ContentType = "application/x-www-form-urlencoded",
            int timeout = 0, SecurityProtocolType securityProtocol = SecurityProtocolType.SystemDefault)
        {
            try
            {
                CookieContainer cookieContainer = new CookieContainer();
                byte[] postBytes = System.Text.Encoding.UTF8.GetBytes(postDataStr);
                // 设置提交的相关参数
                ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);
                HttpWebRequest request = WebRequest.Create(RequestUrl) as HttpWebRequest;
                if (timeout > 0)
                {
                    request.Timeout = timeout * 1000;
                }

                request.Method = "POST";
                request.KeepAlive = false;
                request.ContentType = ContentType;
                request.CookieContainer = cookieContainer;
                request.ContentLength = postBytes.Length;

                using (System.IO.Stream reqStream = request.GetRequestStream())
                {
                    reqStream.Write(postBytes, 0, postBytes.Length);
                }
                using (HttpWebResponse response = request.GetResponse() as HttpWebResponse)
                {
                    //在这里对接收到的页面内容进行处理
                    //直到request.GetResponse()程序才开始向目标网页发送post请求
                    System.IO.Stream responseStream = response.GetResponseStream();
                    System.IO.StreamReader reader = new System.IO.StreamReader(responseStream, System.Text.Encoding.GetEncoding("utf-8"));
                    string val = reader.ReadToEnd();
                    return val;
                }
            }
            catch (Exception ex)
            {
                SuperMap.RealEstate.Utility.ErrorLogHelper.Write(ex, "Post请求", "Post请求：" + postDataStr + "，" + RequestUrl);
                return ex.ToString();
            }
        }

        /// <summary>
        /// HTTP报文请求【POST】
        /// </summary>
        /// <param name="jsonData">报文内容</param>
        /// <param name="url">请求地址</param>
        /// <param name="contentType">资源的媒体类型</param>
        /// <param name="timeoutSeconds">超时时间</param>
        /// <param name="acceptType">请求的接受类型</param>
        /// <param name="headers">请求头</param>
        /// <returns></returns>
        public static string HttpUrlPost(string jsonData, string url, string contentType,
            int timeoutSeconds, string acceptType, Dictionary<string, string> headers)
        {
            try
            {
                // 创建 HttpWebRequest
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
                request.Method = "POST";  // 设置请求方法为 POST
                request.ContentType = contentType;  // 设置请求体的 ContentType
                if (!string.IsNullOrWhiteSpace(acceptType))
                {
                    request.Accept = acceptType;  // 设置请求的接受类型
                }
                else
                {
                    request.Accept = "*/*";
                }
                if (string.IsNullOrWhiteSpace(HttpContext.Current.Request.UserAgent))
                {
                    request.UserAgent = "Windows Server2012R2;WebApi 4.0";
                }
                else
                {
                    request.UserAgent = HttpContext.Current.Request.UserAgent;
                }
                request.Timeout = timeoutSeconds * 1000;  // 设置超时时间，单位为毫秒

                // 添加请求头
                if (headers != null)
                {
                    foreach (var header in headers)
                    {
                        request.Headers.Add(header.Key, header.Value);
                    }
                }

                // 写入请求体
                using (StreamWriter writer = new StreamWriter(request.GetRequestStream()))
                {
                    writer.Write(jsonData);
                    writer.Flush();
                }

                // 获取响应
                using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
                {
                    // 如果请求成功，读取返回内容
                    using (StreamReader reader = new StreamReader(response.GetResponseStream()))
                    {
                        return reader.ReadToEnd();
                    }
                }
            }
            catch (WebException ex)
            {
                // 处理错误（如超时、网络错误等）
                using (StreamReader reader = new StreamReader(ex.Response.GetResponseStream()))
                {
                    string errorResponse = reader.ReadToEnd();
                    return $"Error: {ex.Message}, Response: {errorResponse}";
                }
            }
            catch (Exception ex)
            {
                // 处理其他类型的异常
                return $"Exception: {ex.Message}";
            }
        }

        public static bool CheckValidationResult(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
        {
            return true;
        }
        #endregion

        #region 方法 -> HTTP报文请求【GET】
        /// <summary>
        /// HTTP报文请求【GET】
        /// </summary>
        /// <param name="RequestUrl">请求url</param>
        /// <param name="ContentType">资源的媒体类型，默认application/x-www-form-urlencoded</param>
        /// <param name="timeout">超时时间（TCP连接建立的时间和整个请求完成的时间超出了设置的时间，就抛出异常，程序中断）</param>
        /// <returns></returns>
        public static string HttpUrlGet(string RequestUrl,
            string ContentType = "application/x-www-form-urlencoded", int timeout = 0)
        {
            try
            {
                // 设置提交的相关参数
                ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(CheckValidationResult);
                //根据url创建HttpWebRequest对象   
                HttpWebRequest objRequest = (HttpWebRequest)WebRequest.Create(RequestUrl);
                objRequest.Method = "get";
                objRequest.KeepAlive = false;
                objRequest.ContentType = ContentType;
                if (timeout > 0)
                {
                    objRequest.Timeout = timeout * 1000;
                }
                //读取服务器返回信息  
                HttpWebResponse objResponse = (HttpWebResponse)objRequest.GetResponse();
                //using作为语句，用于定义一个范围，在此范围的末尾将释放对象  
                using (StreamReader sr = new StreamReader(objResponse.GetResponseStream()))
                {
                    //ReadToEnd适用于小文件的读取，一次性的返回整个文件
                    string Result = sr.ReadToEnd();
                    sr.Close();

                    return Result;
                }
            }
            catch (Exception ex)
            {
                SuperMap.RealEstate.Utility.ErrorLogHelper.Write(ex, "Get请求", "Get请求：" + RequestUrl);
                return ex.ToString();
            }
        }
        #endregion

        #region 方法 -> 使用Post form-data方法上传数据、文件
        /// <summary>
        /// 使用Post form-data方法上传数据、文件
        /// </summary>
        /// <param name="url"></param>
        /// <param name="formItems">Post表单内容</param>
        /// <param name="cookieContainer"></param>
        /// <param name="timeOut">默认20秒</param>
        /// <param name="refererUrl">Referer HTTP 标头</param>
        /// <param name="encoding">响应内容的编码类型（默认utf-8）</param>
        /// <returns></returns>
        public static string PostForm(string url, List<Model.FormItemModel> formItems, CookieContainer cookieContainer = null,
            string refererUrl = null, Encoding encoding = null, int timeOut = 20000)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);

            #region 初始化请求对象
            request.Method = "POST";
            request.Timeout = timeOut;
            request.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8";
            request.KeepAlive = true;
            if (string.IsNullOrWhiteSpace(HttpContext.Current.Request.UserAgent))
            {
                request.UserAgent = "Windows Server2012R2;WebApi 4.0";
            }
            else
            {
                request.UserAgent = HttpContext.Current.Request.UserAgent;
            }
            if (!string.IsNullOrEmpty(refererUrl))
            {
                request.Referer = refererUrl;
            }
            if (cookieContainer != null)
            {
                request.CookieContainer = cookieContainer;
            }
            #endregion

            string boundary = "----" + DateTime.Now.Ticks.ToString("x");//分隔符
            request.ContentType = string.Format("multipart/form-data; boundary={0}", boundary);
            //请求流
            var postStream = new MemoryStream();

            #region 处理Form表单请求内容
            //是否用Form上传文件
            var formUploadFile = formItems != null && formItems.Count > 0;
            if (formUploadFile)
            {
                //文件数据模板
                string fileFormdataTemplate =
                    "\r\n--" + boundary +
                    "\r\nContent-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"" +
                    "\r\nContent-Type: application/octet-stream" +
                    "\r\n\r\n";
                //文本数据模板
                string dataFormdataTemplate =
                    "\r\n--" + boundary +
                    "\r\nContent-Disposition: form-data; name=\"{0}\"" +
                    "\r\n\r\n{1}";
                foreach (var item in formItems)
                {
                    string formdata = null;
                    if (item.IsFile)
                    {
                        //上传文件
                        formdata = string.Format(
                            fileFormdataTemplate,
                            item.Key, //表单键
                            item.FileName);
                    }
                    else
                    {
                        //上传文本
                        formdata = string.Format(
                            dataFormdataTemplate,
                            item.Key,
                            item.Value);
                    }

                    //统一处理
                    byte[] formdataBytes = null;
                    //第一行不需要换行
                    if (postStream.Length == 0)
                        formdataBytes = Encoding.UTF8.GetBytes(formdata.Substring(2, formdata.Length - 2));
                    else
                        formdataBytes = Encoding.UTF8.GetBytes(formdata);
                    postStream.Write(formdataBytes, 0, formdataBytes.Length);

                    //写入文件内容
                    if (item.FileContent != null && item.FileContent.Length > 0)
                    {
                        using (var stream = item.FileContent)
                        {
                            byte[] buffer = new byte[1024];
                            int bytesRead = 0;
                            while ((bytesRead = stream.Read(buffer, 0, buffer.Length)) != 0)
                            {
                                postStream.Write(buffer, 0, bytesRead);
                            }
                        }
                    }
                }
                //结尾
                var footer = Encoding.UTF8.GetBytes("\r\n--" + boundary + "--\r\n");
                postStream.Write(footer, 0, footer.Length);

            }
            else
            {
                request.ContentType = "application/x-www-form-urlencoded";
            }
            #endregion

            request.ContentLength = postStream.Length;

            #region 输入二进制流
            if (postStream != null)
            {
                postStream.Position = 0;
                //直接写入流
                Stream requestStream = request.GetRequestStream();

                byte[] buffer = new byte[1024];
                int bytesRead = 0;
                while ((bytesRead = postStream.Read(buffer, 0, buffer.Length)) != 0)
                {
                    requestStream.Write(buffer, 0, bytesRead);
                }

                ////debug
                //postStream.Seek(0, SeekOrigin.Begin);
                //StreamReader sr = new StreamReader(postStream);
                //var postStr = sr.ReadToEnd();
                postStream.Close();//关闭文件访问
            }
            #endregion

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            if (cookieContainer != null)
            {
                response.Cookies = cookieContainer.GetCookies(response.ResponseUri);
            }

            using (Stream responseStream = response.GetResponseStream())
            {
                using (StreamReader myStreamReader = new StreamReader(responseStream, encoding ?? Encoding.UTF8))
                {
                    string retString = myStreamReader.ReadToEnd();
                    return retString;
                }
            }
        }
        #endregion

        #region 方法 -> 请求移动业务的接口
        /// <summary>
        /// 请求移动业务的接口
        /// </summary>
        /// <param name="parameters">URL后面的参数</param>
        /// <returns></returns>
        public static string PostMobileService(string parameters, string provinceCode)
        {
            string reString = "";
            try
            {
                string _BaseUrl = ConfigurationManager.AppSettings[provinceCode];
                string RequestUrl = _BaseUrl + parameters;
                reString = HttpUrlPost(parameters, RequestUrl);
            }
            catch (Exception ex)
            {
                reString = "error:" + ex.Message;
            }
            return reString;
        }
        #endregion
    }
}