package main

import (
	"flag"
	"io"
	"log"
	"net"
	"net/http"
	"net/http/httputil"
	"time"
)

func main() {
	port := flag.String("p", "8889", "port to bind to")
	flag.Parse()

	log.Printf("listening on %s", *port)
	if err := http.ListenAndServe(":"+*port, http.HandlerFunc(echo)); err != nil {
		panic(err)
	}
}
func echo(w http.ResponseWriter, r *http.Request) {
	b, _ := httputil.DumpRequest(r, true)
	log.Printf("DUMP:\n%s", b)
	u := *r.URL
	u.Path = ""
	proxy := httputil.NewSingleHostReverseProxy(&u)
	proxy.ServeHTTP(w, r)
}

func echo2(w http.ResponseWriter, r *http.Request) {
	log.Printf("echo start")
	dest_conn, err := net.DialTimeout("tcp", r.Host, 10*time.Second)
	if err != nil {
		http.Error(w, err.Error(), http.StatusServiceUnavailable)
		return
	}
	log.Printf("echo dialed")
	hijacker, ok := w.(http.Hijacker)
	if !ok {
		http.Error(w, "Hijacking not supported", http.StatusInternalServerError)
		return
	}
	client_conn, _, err := hijacker.Hijack()
	if err != nil {
		http.Error(w, err.Error(), http.StatusServiceUnavailable)
	}
	log.Printf("echo hijacked")

	transfer := func(destination io.WriteCloser, source io.ReadCloser) {
		defer destination.Close()
		defer source.Close()
		io.Copy(destination, source)
	}

	go transfer(dest_conn, client_conn)
	go transfer(client_conn, dest_conn)
	log.Printf("echo transferred")
}