I'm not a native-speaker, so sometimes future tense (be going to, will) is tricky to me.
a. If it rains this weekend, I'm gonna stay home.
b. If it rains this weekend, I will stay home.
c. If this happens again, they're gonna lose everything.
d. If this happens again, they will lose everything.
I wrote some sentences with be going to and will. So, which are correct in these sentences? All of them correct or interchangeable? Are some awkward?