I am trying to allow admins to create nested criteria to as many levels deep as they like.
Everything extends "Criterion", including "Activity" (things that users have to complete) and "Achievement" (which are rewarded based on the criterion).
"Achievement", since it extends "Criterion", can be nested. This way, admins can create complex structures.
It is all working with has_many just fine. But this means that as soon as I add an "Activity" or "Achievement" to more than one "Criterion", it loses its relationship with the one it was added to first.
So I now have many_many => "Criterion" and belongs_many_many "Criteria" in "Criterion". But it isn't allowing me to add any children, nothing ever makes it into the Criterion_Criteria table...
Anything I should be looking out for?