Verb-ば form + ~のに, い-Adjective-ば form + ~のに, な-Adjective + であれば + ~のに, Noun + であれば + ~のに
Long explanation:
The ~ば~のに grammar point is used to express regret or dissatisfaction about a situation that didn't happen or expressing a contrary view of the actual situation. It can be translated as 'if only' or 'wish' in English. The formation differs depending on whether it is used with a verb, い-adjective, な-adjective, or noun.