package signin

import (
	"crypto/rand"
	"encoding/hex"
	"net/http"

	"tug/internal/storage"
)

const (
	BrowserCookie = "__Host-authsvc_browser"
	browserMaxAge = 400 * 24 * 60 * 60
)

func browserMarker(r *http.Request) (string, bool) {
	c, err := r.Cookie(BrowserCookie)
	if err != nil || !storage.ValidBrowser(c.Value) {
		return "", false
	}
	return c.Value, true
}

func newBrowserMarker() string {
	b := make([]byte, storage.BrowserMarkerLength/2)
	rand.Read(b)
	return hex.EncodeToString(b)
}

func setBrowser(w http.ResponseWriter, marker string) {
	http.SetCookie(w, &http.Cookie{Name: BrowserCookie, Value: marker, Path: "/", MaxAge: browserMaxAge, Secure: true, HttpOnly: true, SameSite: http.SameSiteLaxMode})
}

func ensureBrowser(w http.ResponseWriter, r *http.Request) string {
	if marker, ok := browserMarker(r); ok {
		return marker
	}
	marker := newBrowserMarker()
	setBrowser(w, marker)
	return marker
}