Navigation Controller

I would like to build a navigation system where the admin can modify menus dynamically. I need a top , left, right, footer navigation. So i made my navigation controller/model with tree behaviour. So those 4 menus are in there, add sections within them. But cant seem to come up with the best way to mange the links/pages for each. User adds a new link called contact us for example. How to set it so contact us goes to contact controller? Easy to say type in slug "/contact" but if the end admin user is a complete moron you cant trust that they wont type in "contact us" and then goes no where.

 

And how would I build the navigations and save them...i mean no need to build the footer/top nav on every page view, since they wont change from page to page. What is the best way to get the data to build the menus and save them so your not requesting buildTopNav() buildFooterNav() type thing.

 

Any ideas? Pointers?

 

Thanks.

 

Dave