package main

import (
	"crypto/md5"
	"crypto/subtle"
	"encoding/hex"
	"html/template"
	"log"
	"net/http"
	"strconv"
	"time"
)

type App struct {
	Store
	Template *template.Template
}

func logMux(handler http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		t := time.Now()
		handler.ServeHTTP(w, r)
		log.Println(r.Method, r.URL.Path, time.Since(t))
	})
}

func (app *App) validateHandler(w http.ResponseWriter, r *http.Request) {
	c, err := r.Cookie("id")
	//log.Println(r.Header.Get("X-Original-URI"))
	//log.Println(r.Host)
	if err != nil {
		w.WriteHeader(http.StatusUnauthorized)
	} else {
		if s, ok := app.GetSession(c.Value); ok {
			w.Header().Set("X-Remote-User", strconv.FormatInt(s.UserId, 10))
			w.WriteHeader(http.StatusOK)
		} else {
			log.Println("Session does not exist:", c.Value)
			w.WriteHeader(http.StatusForbidden)
		}
	}
}

func (app *App) loginHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method == http.MethodPost {
		if err := r.ParseForm(); err != nil {
			panic(err)
		} else {
			username := r.Form.Get("username")
			password := r.Form.Get("password")
			hash := md5.Sum([]byte(password))
			dst := make([]byte, hex.EncodedLen(md5.Size))
			hex.Encode(dst, hash[:])
			u, ok := app.GetUser(username)
			if ok && subtle.ConstantTimeCompare(u.Password, dst) == 1 {

			} else {

			}
		}
	} else if r.Method == http.MethodGet {
		app.Template.ExecuteTemplate(w, "login.tmpl", nil)
	}

}

func main() {
	//log.SetFlags(log.LstdFlags)
	store := NewPgStore()
	template := template.Must(template.New("").ParseGlob("templates/*.tmpl"))
	app := &App{store, template}
	http.HandleFunc("/validate", app.validateHandler)
	http.HandleFunc("/login", app.loginHandler)
	if err := http.ListenAndServe(":8080", logMux(http.DefaultServeMux)); err != nil {
		panic(err)
	}
}