a user begins to edit any node. after they start that process, but before the node is presented, i need to check some conditions specific to the node and route the user accordingly.

for example: a user clicks the edit button on a node. the module checks some user perms and for an existing working copy of that node. if there is an existing copy, then direct them to that node. if there is no existing working copy, ask for comfirmation to create a new working copy and then direct them to the new working copy's edit form.

my first thought is nodeapi. however it seems there is no $op at this point in the process. the only other option i can think of is to edit node_menu(). i would really like to avoid this, so i am polling here for any better ideas. hopefully im just missing something obvious. :-P

thanks in advance,
buchanae