Which tense follows "si" in present, past, etc.

[rkeyster]

Hi,

I'm sure this has been done before, but I'd really appreciate it if someone could clarify the tenses that follow "si" in various situations.

I know that the "regular," present tense subjunctive does NOT follow si.

For example, if I want to say:

If he comes, I will become nervous.

That is (I think!):

Si viene, me pongo nervioso. (no subjunctive used)

However, I've noticed that in sentences like the following (copied and pasted from the haber + haber thread), a form of the subjunctive is used.

Habría sido bonito si no hubiera llovido en la boda. (It would have been nice if it hadn't rained at the party).

So if I want to say "If it had/hadn't....", would I always use the above form of the subjunctive (highlighted in red)?

Would I then use the past subjunctive if I wanted to simply say, "If it didn't rain..." (si no lloviera...)

I don't want to take up too much of anyone's time, so if anyone knows a website/page that lists the different "si" situations and which subjunctive/non-subjunctive verb tense corresponds, I'd be much obliged!