// Command dpi-protocol-probe for probing network server protocols.
package main

import (
	"flag"
	"fmt"
	"net"
	"os"
	"time"

	"git.maze.io/go/dpi/protocol"
)

func main() {
	networkFlag := flag.String("network", "tcp", "Network type to use for probing")
	timeoutFlag := flag.Duration("timeout", 30*time.Second, "Timeout")
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage of %s [<flags>] <address>:\n\n", os.Args[0])
		fmt.Fprintln(os.Stderr, "Available flags:")
		flag.PrintDefaults()
		fmt.Fprintln(os.Stderr, "\nRequired arguments:")
		fmt.Fprintln(os.Stderr, "  address string")
		fmt.Fprintln(os.Stderr, "\tNetwork address to connect to (ie localhost:22)")
		os.Exit(0)
	}
	flag.Parse()

	if flag.NArg() != 1 {
		flag.Usage()
	}

	address := flag.Arg(0)
	if _, _, err := net.SplitHostPort(address); err != nil {
		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
		os.Exit(2)
	}

	protocol, confidence, err := protocol.ProbeTimeout(*networkFlag, address, *timeoutFlag)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Probing address %q failed: %v\n", address, err)
		os.Exit(3)
	}

	fmt.Printf("Protocol at address %q is %s version %s (confidence %g%%)\n", address, protocol.Type, protocol.Version, confidence*100)
}