Help with intercepting middleware, and writing responses about templ HOT 4 CLOSED

func isHtml(w http.ResponseWriter) bool {
	return strings.HasPrefix(w.Header().Get("Content-Type"), "text/html")
}

type App struct {
	Router *chi.Mux
}

func NewApp() *App {
	router := chi.NewRouter()
	router.Use(middleware.Logger)
	return &App{
		Router: chi.NewRouter(),
	}
}

func (a *App) Middleware(next http.HandlerFunc) http.HandlerFunc {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if !isHtml(w) {
			next.ServeHTTP(w, r)
			return
		}

		w.Write([]byte("<p>Loading...</p>"))
		next.ServeHTTP(w, r)
	})
}

func (a *App) Component(route string, handler http.HandlerFunc) {
	a.Router.Get(route, a.Middleware(handler))
}

func (a *App) Listen(port string) {
	http.ListenAndServe(port, a.Router)
}

func main() {
	app := NewApp()

	app.Component("/", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Add("Content-Type", "text/html")
		views.Component().Render(context.Background(), w)
	})

	app.Listen(":3000")
}