package main

import (
	"fmt"
	"log"
	"net/http"
	"time"
)

type LoggingHTTPHandler struct {
    Handler http.Handler
}

func (l *LoggingHTTPHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {

    t1 := time.Now().UTC()

    l.Handler.ServeHTTP(w, r)

    log.Println(
        fmt.Sprintf("%s %s %s %v", getIP(r), r.Method, r.URL.Path, time.Since(t1)),
    )
    
}

func NewLogger(handler http.Handler) LoggingHTTPHandler {
    return LoggingHTTPHandler{handler}
}

func getIP(r *http.Request) string {

    RealIP := r.Header.Get("X-Real-IP")
    if RealIP == "" {
        return r.RemoteAddr
    }
    return RealIP
}