The ruling on one who prays the funeral prayer with the imam while thinking he is praying an obligatory prayer

Q: The brother M. A. M. from Al-Ula says in his question: I entered the mosque to perform the Zuhr prayer and found the people standing and praying. So I said the takbir with them, and after a short while I realized that they were praying over a funeral. I became confused and broke off the prayer, then I said the takbir of intention again to make up the Zuhr prayer, and I did not complete the funeral prayer with them. What is the ruling on what I did, and was my action bad? I ask you to be kind enough to answer my question.

A: What is prescribed for you in such a matter is to intend the funeral prayer once you know that it is a funeral prayer, then say the takbir and complete the funeral prayer with them, and make up any takbirs you missed if you missed any. Then, after that, you pray the Zuhr prayer, because the funeral prayer is missed if one does not perform it, whereas the Zuhr prayer is not missed because its time is wide. May Allah guide them all.