55822 User/File managment script

Hello thanks for your intrest. What i need is a secure file mangement script. I need this to be very secure. What i want to be able to do as the admin is create user accounts WITH user name and password. There will be 2 user levels, 1 will be normal user and the other will be a super user who will have all the rights as the admin. As the admin i would like to be able to upload files to the user-area for my users to veiw and/or download. All files should be able to be sorted by upload date, and file name. There should also be an internal search script that a user could use to search through the files for a certain file name or upload date. I should also be able to create an unlimited number of folders in which to upload these files to. I would also like the ability to limit access to some folders to specific users only. I'm not sure if this is possible but i would also like a feature that allows users to search for a certatin keyword or phrase within a txt or word document that's uploaded in the system. IF THIS IS POSSIBLE PLEASE MAKE IT KNOWN CAUSE I REALLY WANT THIS FEATURE. All in all this is a pretty striaght forward easy project.