package admin

import (
	"encoding/base64"
	"encoding/json"
	"net/http"
)

const flashCookieName = "hold_admin_flash"

// setFlash sets a flash message cookie
func setFlash(w http.ResponseWriter, r *http.Request, category, message string) {
	flash := Flash{
		Category: category,
		Message:  message,
	}

	data, err := json.Marshal(flash)
	if err != nil {
		return
	}

	encoded := base64.URLEncoding.EncodeToString(data)
	secure := r.TLS != nil || r.Header.Get("X-Forwarded-Proto") == "https"

	http.SetCookie(w, &http.Cookie{
		Name:     flashCookieName,
		Value:    encoded,
		Path:     "/admin",
		MaxAge:   60, // 1 minute - should be consumed on next page load
		HttpOnly: true,
		Secure:   secure,
		SameSite: http.SameSiteLaxMode,
	})
}

// getFlash retrieves and clears the flash message
func getFlash(r *http.Request, ui *AdminUI) *Flash {
	cookie, err := r.Cookie(flashCookieName)
	if err != nil {
		return nil
	}

	data, err := base64.URLEncoding.DecodeString(cookie.Value)
	if err != nil {
		return nil
	}

	var flash Flash
	if err := json.Unmarshal(data, &flash); err != nil {
		return nil
	}

	return &flash
}

// clearFlash clears the flash cookie (called after displaying)
func clearFlash(w http.ResponseWriter) {
	http.SetCookie(w, &http.Cookie{
		Name:     flashCookieName,
		Value:    "",
		Path:     "/admin",
		MaxAge:   -1,
		HttpOnly: true,
		SameSite: http.SameSiteLaxMode,
	})
}