using System;
using System.Collections;
using System.Collections.Generic;
using System.Configuration;
using System.IO;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading.Tasks;
using System.Timers;
using WebScanner.Tools;

namespace WebScanner
{
    public class ScannerService
    {
        private ScannerService()
        {
            //int msInterval = Convert.ToInt16(ConfigurationManager.AppSettings["TimeSpan"]);
            int msInterval = AppSetting.GetInt("TimeInterval");

            Timer timer = new Timer();
            timer.Elapsed += Timer_Elapsed;
            timer.Enabled = true;
            timer.Interval = msInterval * 1000;
        }
        private void Timer_Elapsed(object sender, ElapsedEventArgs e)
        {
            //var ms = ConfigurationManager.AppSettings["HostApi"].ToString();
            var ms = AppSetting.GetValue("HostApi");
            var webs = ms.Split(';');
            foreach (var web in webs)
            {
                Action ac = () => HttpRequest(web, contenttype: "text/html; charset=utf-8");
                ac.Invoke();
            }
        }
        /// <summary>
        /// 不做catch处理，需要在外部做
        /// </summary>
        /// <param name="url"></param>
        /// <param name="method">默认GET，空则补充为GET</param>
        /// <param name="contenttype">默认json，空则补充为json</param>
        /// <param name="header">请求头部</param>
        /// <param name="data">请求body内容</param>
        /// <returns></returns>
        public static string HttpRequest(string url, string method = "GET", string contenttype = "application/json;charset=utf-8", Hashtable header = null, string data = null)
        {
            typeof(ScannerService).LogInfo($"request start:{url}");
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
            request.Method = string.IsNullOrEmpty(method) ? "GET" : method;
            request.ContentType = string.IsNullOrEmpty(contenttype) ? "application/json;charset=utf-8" : contenttype;
            request.Timeout = 30000;
            if (header != null)
            {
                foreach (var i in header.Keys)
                {
                    request.Headers.Add(i.ToString(), header[i].ToString());
                }
            }
            if (!string.IsNullOrEmpty(data))
            {
                Stream requestStream = request.GetRequestStream();
                byte[] bytes = Encoding.UTF8.GetBytes(data);
                requestStream.Write(bytes, 0, bytes.Length);
                requestStream.Close();
            }
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            Stream responseStream = response.GetResponseStream();
            StreamReader streamReader = new StreamReader(responseStream ?? throw new InvalidOperationException(), Encoding.GetEncoding("utf-8"));
            string re = streamReader.ReadToEnd();
            streamReader.Close();
            responseStream.Close();
            typeof(ScannerService).LogInfo($"request end:{re.Substring(0,100)}");
            return re;
        }
        private static volatile ScannerService _scannerService = null;
        public static ScannerService GetSingleObj()
        {
            return _scannerService ?? (_scannerService = new ScannerService());
        }
    }
}