package main

import (
	"fmt"
	"log"
	"net"
	"time"
)

// Client launch the client
func Client() {
	addr, _ := net.ResolveUDPAddr("udp", "localhost:8000")
	c, err := net.DialUDP("udp", nil, addr)
	if err != nil {
		panic("Dial failed ...")
	}
	// RTT := make([]int, 10)
	maxRTT := 0
	minRTT := 0x3f3f3f3f
	const total int = 10
	// packet超时时间
	const mtime = time.Second * 3
	lossNum := 0
	for i := 0; i < total; i++ {
		start := time.Now()
		msg := fmt.Sprintf("Ping %d %s", i, start)
		c.Write([]byte(msg))
		buf := make([]byte, 1024)
		// c.Read(buf)
		// log.Printf("%s", buf)
		c.SetReadDeadline(time.Now().Add(time.Second))
		_, err := c.Read(buf)
		if err != nil {
			if timeErr := err.(net.Error); timeErr != nil && timeErr.Timeout() == true {
				log.Println("数据包接收超时...")
				lossNum++
				continue
			}
		}

		duration := time.Since(start)
		d := int(duration / time.Millisecond)
		if d > maxRTT {
			maxRTT = d
		}
		if d < minRTT {
			minRTT = d
		}
		log.Printf("sucess:ping %d;RTT:%d ms", i, d)
	}

	log.Println("-------------------")
	log.Printf("loss:%d%%|maxRTT:%d ms|minRTT:%d ms", lossNum*100/total, maxRTT, minRTT)
}

func main() {
	Client()
}