Adding PHP code?

I have a php code, which displays movie description by accessing IMDB.

This code, if called without parameter, display a search form.
Entered a title, it calls itself with ?name=xxxx, which displays a list of movie title that matches.
If a movie title gets clicked, it calls again itself with ?mid=xxx

Can I just insert this PHP code into a story, or whatever node and it will work like it dopes if called directly from the browser?
This php also includes some other classes. How about the path to this classes? How can the php code find them if the code is in a node?