package main

import (
	"errors"
	"flag"
	"log"
	"log/syslog"
	"os"
	"os/signal"
	"path"
	"syscall"
	"tunnel/pkg/config"
	"tunnel/pkg/server"
)

var (
	debugFlag  = flag.Bool("d", false, "debug: print time and source info")
	syslogFlag = flag.Bool("s", false, "log output to syslog instead of stdout")
)

func initLog() {
	var logFlags int

	if *debugFlag {
		logFlags |= log.Ldate | log.Ltime | log.Lshortfile
	}

	log.SetFlags(logFlags)

	if *syslogFlag {
		sysLog, err := syslog.New(syslog.LOG_INFO, "tunneld")
		if err != nil {
			log.Fatal(err)
		}

		log.SetOutput(sysLog)
	}
}

func sighandler(c chan os.Signal, s *server.Server) {
	var try bool

	for sig := range c {
		if try {
			log.Fatal("force exit")
		}

		log.Printf("catch signal: %s", sig)
		try = true
		s.Stop()
	}
}

func getSocketPath() string {
	s, err := config.GetSocketPath()
	if err != nil {
		log.Fatal(err)
	}

	if err := os.Mkdir(path.Dir(s), 0700); err != nil {
		if !errors.Is(err, syscall.EEXIST) {
			log.Fatal(err)
		}
	}

	return s
}

func main() {
	flag.Parse()
	initLog()

	s, err := server.New(getSocketPath())
	if err != nil {
		log.Fatal(err)
	}

	var c = make(chan os.Signal)

	signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)

	go sighandler(c, s)

	log.Print("ready")

	s.Run()

	log.Print("exit")
}