I wanted to note, Wiktionary is stating “cię” here is accusative, but I believe it’s genitive due to the negation “nie będzie”. Wiktionary is also saying “czały dzień” is nominative, but here it’s for a duration of time, so I think it’s supposed to be accusative, no?
Accusative is the same as nominative for cały dzień. I think you might be right about the ciebie instead of cię, because was, jej, go, ich etc. would be correct. However, it strangely sounds correct, @Hyacinthe ? Maybe both cię and ciebie are genitive, like go and jego, I don’t know