package netProgram

import (
	"log"
	"net"
	"sync"
	"time"
)

// 客户端
func TcpClient() {
	// tcp服务端地址
	//serverAddress := "127.0.0.1:5678"

	// tcp协议类型
	serverAddress := "[::1]:5678" // IPv6
	//serverAddress := "127.0.0.1:5678" // IPv4

	// 模拟多客户端
	// 并发的客户端请求
	num := 10
	wg := sync.WaitGroup{}
	wg.Add(num)
	for i := 0; i < num; i++ {
		// 并发请求
		go func(wg *sync.WaitGroup) {
			defer wg.Done()
			// A. 建立连接
			conn, err := net.Dial(tcp, serverAddress)
			if err != nil {
				log.Println(err)
				return
			}
			// 保证关闭
			defer conn.Close()
			log.Printf("connection is establish, client addr is %s\n", conn.LocalAddr())
		}(&wg)
	}

	wg.Wait()
}

func TcpTimeoutClient() {
	// tcp服务端地址
	serverAddress := "192.168.110.123:5678" // IPv6 4

	// 模拟多客户端
	// 并发的客户端请求
	num := 10
	wg := sync.WaitGroup{}
	wg.Add(num)
	for i := 0; i < num; i++ {
		// 并发请求
		go func(wg *sync.WaitGroup) {
			defer wg.Done()
			// A. 建立连接
			conn, err := net.DialTimeout(tcp, serverAddress, time.Second)
			//conn, err := net.Dial(tcp, serverAddress)
			if err != nil {
				log.Println(err)
				return
			}
			// 保证关闭
			defer conn.Close()
			log.Printf("connection is establish, client addr is %s\n", conn.LocalAddr())
		}(&wg)
	}

	wg.Wait()
}

func TcpBacklogClient() {
	// tcp服务端地址
	serverAddress := "127.0.0.1:5678" // IPv6 4

	// 模拟多客户端
	// 并发的客户端请求
	num := 256
	wg := sync.WaitGroup{}
	wg.Add(num)
	for i := 0; i < num; i++ {
		// 并发请求
		go func(wg *sync.WaitGroup, no int) {
			defer wg.Done()
			// A. 建立连接
			conn, err := net.DialTimeout(tcp, serverAddress, time.Second)
			//conn, err := net.Dial(tcp, serverAddress)
			if err != nil {
				log.Println(err)
				return
			}
			// 保证关闭
			defer conn.Close()
			log.Printf("%d: connection is establish, client addr is %s\n", no, conn.LocalAddr())
		}(&wg, i)

		time.Sleep(30 * time.Millisecond)
	}

	wg.Wait()
}