using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;

namespace BLL.Common
{
    public class HttpHelper
    {
        /// <summary>
        /// Http Get Request
        /// </summary>
        /// <param name="url"></param>
        /// <returns></returns>
        public static string HttpGetRequest(string url)
        {
            string strGetResponse = string.Empty;
            try
            {
                var getRequest = CreateHttpRequest(url,"GET", "");
                var getResponse = getRequest.GetResponse() as HttpWebResponse;
                strGetResponse = GetHttpResponse(getResponse, "GET");
            }
            catch (Exception ex)
            {
                strGetResponse = ex.Message;
            }
            return strGetResponse;
        }

        /// <summary>
        /// Http Post Request
        /// </summary>
        /// <param name="url"></param>
        /// <param name="postJsonData"></param>
        /// <returns></returns>
        public static string HttpPostRequest(string url, string postJsonData,string token)
        {
            BLL.ErrLogInfo.WriteLog("token=" + token);
            string strPostReponse = string.Empty;
            try
            {
                var postRequest = CreateHttpRequest(url, "POST",token, postJsonData);
                var postResponse = postRequest.GetResponse() as HttpWebResponse;
                strPostReponse = GetHttpResponse(postResponse, "POST");
                BLL.ErrLogInfo.WriteLog("result=" + strPostReponse);
            }
            catch (Exception ex)
            {
                strPostReponse = ex.Message;
                BLL.ErrLogInfo.WriteLog("error=" + ex.Message);
            }
            return strPostReponse;
        }

        private static HttpWebRequest CreateHttpRequest(string url, string requestType, string token, params object[] strJson)
        {
            HttpWebRequest request = null;
            const string get = "GET";
            const string post = "POST";
            if (string.Equals(requestType, get, StringComparison.OrdinalIgnoreCase))
            {
                request = CreateGetHttpWebRequest(url);
            }
            if (string.Equals(requestType, post, StringComparison.OrdinalIgnoreCase))
            {
                request = CreatePostHttpWebRequest(url, strJson[0].ToString(),token);
            }
            return request;
        }

        private static HttpWebRequest CreateGetHttpWebRequest(string url)
        {
            var getRequest = HttpWebRequest.Create(url) as HttpWebRequest;
            getRequest.Method = "GET";
            getRequest.Timeout = 5000;
            getRequest.ContentType = "text/html;charset=UTF-8";
            getRequest.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
            return getRequest;
        }
        private static HttpWebRequest CreatePostHttpWebRequest(string url, string postData,string token)
        {
            var postRequest = HttpWebRequest.Create(url) as HttpWebRequest;
            postRequest.KeepAlive = false;
            postRequest.Method = "POST";
            postRequest.ContentType = "application/x-www-form-urlencoded";
            if (!string.IsNullOrEmpty(token))
            {
                postRequest.ContentType = "application/json";
                postRequest.Headers.Add("token_app", token);
            }
            postRequest.ContentLength = postData.Length;
            postRequest.AllowWriteStreamBuffering = false;
            StreamWriter writer = new StreamWriter(postRequest.GetRequestStream(), Encoding.ASCII);
            writer.Write(postData);
            writer.Flush();
            return postRequest;
        }

        private static string GetHttpResponse(HttpWebResponse response, string requestType)
        {
            var responseResult = "";
            const string post = "POST";
            string encoding = "UTF-8";
            if (string.Equals(requestType, post, StringComparison.OrdinalIgnoreCase))
            {
                encoding = response.ContentEncoding;
                if (encoding == null || encoding.Length < 1)
                {
                    encoding = "UTF-8";
                }
            }
            using (StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.GetEncoding(encoding)))
            {
                responseResult = reader.ReadToEnd();
            }
            return responseResult;
        }
    }
}