// Copyright 2011 Google Inc. All rights reserved.

// Use of this source code is governed by the Apache 2.0

// license that can be found in the LICENSE file.

// +build !appengine

package internal

import (

	"io"

	"log"

	"net/http"

	"net/url"

	"os"

)

func Main() {

	installHealthChecker(http.DefaultServeMux)

	port := "8080"

	if s := os.Getenv("PORT"); s != "" {

		port = s

	}

	host := ""

	if IsDevAppServer() {

		host = "127.0.0.1"

	}

	if err := http.ListenAndServe(host+":"+port, http.HandlerFunc(handleHTTP)); err != nil {

		log.Fatalf("http.ListenAndServe: %v", err)

	}

}

func installHealthChecker(mux *http.ServeMux) {

	// If no health check handler has been installed by this point, add a trivial one.

	const healthPath = "/_ah/health"

	hreq := &http.Request{

		Method: "GET",

		URL: &url.URL{

			Path: healthPath,

		},

	}

	if _, pat := mux.Handler(hreq); pat != healthPath {

		mux.HandleFunc(healthPath, func(w http.ResponseWriter, r *http.Request) {

			io.WriteString(w, "ok")

		})

	}

}