Re implemnt Ra2 garisson and cnc generls fire base logic

1-like ra2 when a gi or any kind of infantry garisson a building they fire the buildings primary weapon Example:
[building]
primary=Laser
can.be.occupied=yes
Max.number.of.occupant=10
can.occupy .fire=yes
..........................
know for every one inside will fire the structers weapon rather then there own
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2-bring a knew logic that lets the building fire its weapon when its occupied or not like cnc generals fire base