Agr hme roza rkhna h or fajr m meri ankh nhi khul pai to kya subah jb uthe to niyat kr skte h?

Agr wajib roza hai aur koi aysa kam nahi kiya hai jo roze ko batil kare to Zawal (Azan e Zohr) tak aur agr Mustahab roza hai to azan e maghrib se pahle tak niyat kar sakta hai.