package sniff

import (
	"fmt"
	"net"
	"strings"
	"time"

	"go.uber.org/zap"
)

func (d *Device) TCP() error {
	for i := 0; i < 10; i++ {
		addrAndPort := fmt.Sprintf("%s:%s", d.IP, d.Port)
		conn, err := net.DialTimeout("tcp", addrAndPort, time.Second*6)
		if err != nil {
			switch {
			case strings.Contains(err.Error(), "too many open files"):
				zap.S().Debug("系统会话数达到上线，请及时调整")
			default:
				continue
			}
		} else {
			//zap.S().Debugf("Port is opened:%v", addrAndPort)
			d.Reachability = true
			//open的connection需要关闭
			err := conn.Close()
			if err != nil {
				zap.S().Debugf("TCP close failed,%v", err.Error())
			}
			return err
		}
	}
	return nil
}