Quick question on astral combat, Adepts with weapon focus Options

[FriendoftheDork]

Hey the adept in my group wants to know how he can fight spirits in astral while using astral perception power.

Now, after reading the book I got the impression the rules say you use meat attributes and skills for fighting physical opponents and Astral Combat+Willpower to fight astral ones.

And, astrally projecting mages use mental stats instead of physical ones.

But what about adepts? Do they also use mental stats when fighting astral entities, or do they use physical stats for everything except actually attacking?

Also, weapon foci does the same damage as the weapon right? If it is for instance a sword, does it do charmisma/2 +3 damage? Or strength?