using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;

namespace HXX.Scanner.Biz
{
    /// <summary>
    /// 获取网络状态
    /// </summary>
    public class biz_ping
    {
        /// <summary>
        /// 超时设置
        /// </summary>
        private const int TIME_OUT = 100;
        /// <summary>
        /// 包大小
        /// </summary>
        private const int PACKET_SIZE = 512;
        /// <summary>
        /// 重试次数
        /// </summary>
        private const int TRY_TIMES = 2;
        /// <summary>
        /// 对运行后结果的过滤规则的正则
        /// </summary>
        private static Regex _reg = new Regex(@"时间=(.*?)ms", RegexOptions.Multiline | RegexOptions.IgnoreCase);

        /// <summary>
        /// 调用系统ping命令
        /// </summary>
        /// <param name="strCommandline"></param>
        /// <param name="packetSize"></param>
        /// <returns></returns>
        private static float LaunchPing(string strCommandline, int packetSize)
        {
            Process proc = new Process();
            proc.StartInfo.Arguments = strCommandline;
            proc.StartInfo.UseShellExecute = false;
            proc.StartInfo.CreateNoWindow = true;
            proc.StartInfo.FileName = "ping.exe";
            proc.StartInfo.RedirectStandardInput = true;
            proc.StartInfo.RedirectStandardOutput = true;
            proc.StartInfo.RedirectStandardError = true;

            proc.Start();
            string strBuffer = proc.StandardOutput.ReadToEnd();
            proc.Close();

            //Console.WriteLine( strCommandline );
            //Console.WriteLine( strBuffer );

            return ParseResult(strBuffer, packetSize);
        }

        /// <summary>
        /// 根据ping的结果计时，估算网速
        /// </summary>
        /// <param name="strBuffer"></param>
        /// <param name="packetSize"></param>
        /// <returns></returns>
        private static float ParseResult(string strBuffer, int packetSize)
        {
            if (strBuffer.Length < 1) return 0.0F;

            MatchCollection mc = _reg.Matches(strBuffer);
            if (mc == null || mc.Count < 1 || mc[0].Groups == null) return 0.0F;
            int avg;
            if (!int.TryParse(mc[0].Groups[1].Value, out avg)) return 0.0F;
            if (avg <= 0) return 1024.0F;

            var result= (float)packetSize / avg * 1000 / 1024; 

            return (float)result;
        }

        /// <param name="strHost">主机名或ip</param>
        /// <returns>kbps/s</returns>
        public static float Test(string strHost)
        {
            return LaunchPing(string.Format("{0} -n {1} -l {2} -w {3}", strHost, TRY_TIMES, PACKET_SIZE, TIME_OUT), PACKET_SIZE);
        }

        /// <param name="strHost">主机名或ip</param>
        /// <param name="PacketSize">发送测试包大小</param>
        /// <param name="TimeOut">超时</param>
        /// <param name="TryTimes">测试次数</param>
        /// <returns>kbps/s</returns>
        public static float Test(string strHost, int PacketSize, int TimeOut, int TryTimes)
        {
            return LaunchPing(string.Format("{0} -n {1} -l {2} -w {3}", strHost, TryTimes, PacketSize, TimeOut), PacketSize);
        }
    }
}