package main

import (
    "fmt"
    "log"
    "bytes"
    "net/http"
    "net/url"
    "strings"
    "runtime"

    "github.com/rumblefrog/go-a2s"
    "encoding/json"
)

func newServerQuerier(host string) ([]byte, error) {
    client, err := a2s.NewClient(host)

    if err != nil {
        log.Printf("Creation of client failed: %s", err)
    }

    defer client.Close()

    info, err := client.QueryInfo()

    if err != nil {
        log.Printf("Querying failed: %s", err)
        return []byte("\"error\": \"1\""), nil
    }

    log.Printf("%s - %s\n", host, info.Name)

    buf, err := json.Marshal(info)

    var indented bytes.Buffer
    json.Indent(&indented, buf, "\t", "\t")

    return []byte(indented.String()), err
}

func Log(handler http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		log.Printf("access: %s %s %s", r.RemoteAddr, r.Method, r.URL)
		handler.ServeHTTP(w, r)
	})
}

func httpServer(w http.ResponseWriter, r *http.Request) {
	uriSegments := strings.Split(r.URL.String(), "/")
	host, _ := url.QueryUnescape(uriSegments[2])

	var info, err = newServerQuerier(host)
    if err != nil {
        log.Printf("Got an error while receiving data: %s", err)
    }

	w.Header().Set("Content-Type", "application/json; charset=UTF-8")
	fmt.Fprintf(w, "%s", info)
}

func main() {
	runtime.GOMAXPROCS(runtime.NumCPU())

	http.HandleFunc("/server/", httpServer)
	log.Fatal(http.ListenAndServe(":8080", Log(http.DefaultServeMux)))
}