package main

import (
	"encoding/json"
	"flag"
	"log"
	"os"
	"os/signal"
	"runtime"
	"syscall"

	"github.com/net-byte/vtun/common/cipher"
	"github.com/net-byte/vtun/common/config"
	"github.com/net-byte/vtun/common/netutil"
	"github.com/net-byte/vtun/tcp"
	"github.com/net-byte/vtun/tun"
	"github.com/net-byte/vtun/udp"
	"github.com/net-byte/vtun/ws"
)

func main() {
	config := config.Config{}
	flag.StringVar(&config.CIDR, "c", "172.16.0.10/24", "tun interface cidr")
	flag.IntVar(&config.MTU, "mtu", 1500, "tun mtu")
	flag.StringVar(&config.LocalAddr, "l", ":3000", "local address")
	flag.StringVar(&config.ServerAddr, "s", ":3001", "server address")
	flag.StringVar(&config.Key, "k", "freedom@2022", "key")
	flag.StringVar(&config.Protocol, "p", "wss", "protocol tcp/udp/ws/wss")
	flag.StringVar(&config.DNS, "d", "8.8.8.8:53", "dns address")
	flag.StringVar(&config.WebSocketPath, "path", "/freedom", "websocket path")
	flag.BoolVar(&config.ServerMode, "S", false, "server mode")
	flag.BoolVar(&config.GlobalMode, "g", false, "client global mode")
	flag.BoolVar(&config.Obfs, "obfs", false, "enable data obfuscation")
	flag.IntVar(&config.Timeout, "t", 30, "dial timeout in seconds")
	flag.Parse()
	initConfig(&config)
	go startApp(config)
	quit := make(chan os.Signal, 1)
	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
	<-quit
	stopApp(config)
}

func initConfig(config *config.Config) {
	if !config.ServerMode {
		os := runtime.GOOS
		if os == "linux" {
			config.DefaultGateway = netutil.GetLinuxDefaultGateway()
		} else if os == "darwin" {
			config.DefaultGateway = netutil.GetMacDefaultGateway()
		}
	}
	cipher.GenerateKey(config.Key)
	json, _ := json.Marshal(config)
	log.Printf("init config:%s", string(json))
}

func startApp(config config.Config) {
	switch config.Protocol {
	case "udp":
		if config.ServerMode {
			udp.StartServer(config)
		} else {
			udp.StartClient(config)
		}
	case "tcp":
		if config.ServerMode {
			tcp.StartServer(config)
		} else {
			tcp.StartClient(config)
		}
	case "ws":
		if config.ServerMode {
			ws.StartServer(config)
		} else {
			ws.StartClient(config)
		}
	default:
		if config.ServerMode {
			ws.StartServer(config)
		} else {
			ws.StartClient(config)
		}
	}
}

func stopApp(config config.Config) {
	tun.Reset(config)
	log.Printf("stopped!!!")
}