Android FB login/signup

I´m creating a small APP for Android and i´m using Phonegap, Eclipse and working on Windows. I have been trying to implement the Facebook login/signup but not successful and don´t have the time to figure it out. I have a server up and running MySQL database with my website User Info (Facebook Uid, email, name and more). This is what I need (simple and light programming) Index site with two links. One for sign in and the other for Sign Up. php file on my server to handle the request All files and instructions on how to implement this to my eclipse + well commented code. Signin button Once user is signed in on facebook send a Request to my server to check if user exits. Log user in if he exits, If not error notification. Signup button Once user us signed in on facebook, send his facebook information (name, email, uid) to my server and add a MySQL record. In both cases store user Name and uid as a localstorage varible. As I said, I tried this but was not successful so I will need a well commented code, good instructions on how to implement this into my eclipse and All files (.jar, .java and so on). So I can add my app ID and my database info and get this working. If more information needed PM me. Andres