Barcode generator web app

The objective is to build a web application that generates a sheet or sheets of barcodes on label paper using a barcode generator formula that uses data provided by a user. Functionality: 1. Application has one webpage that allows the user to do the following: a. Enter "UserID": (allowable value is a 6 digit number); application must validate that the value is no more the 6 characters and is numeric b. Enter "Number of Barcodes to Generate": (allowable value is 0 - 100); application must validate that the value is no more the 100 and is numeric c. User clicks the "Generate Barcodes" button. d. Application uses the following formula to create a barcode value = UserID + TIMESTAMP + a 3 digit incremental counter. So for example 1) UserID = 123456 2) Number of Barcodes = 3 3) Timestamp = 2012-02-14 09:34:00 4) Barcodes generated would be: (a). 12345620120214093400001 (b). 12345620120214093400002 (c). 12345620120214093400003 e. Application uses the barcode value to generate a Code-128 barcode for each barcode value created (there are open source PHP barcode generators available online) f. Application must arrange the barcode on a file (probably PDF). Barcodes must be arranged to fit on Avery 5260 label sheets, which has 30 labels that are 1" x 2 5/8" in size per sheet. (http://www.avery.com/avery/en_us/Templates-&-Software/Templates/Labels/Address-Labels/[login to view URL] ) g. User can leverage native print functionality to print the label sheet. Technical requirements. - Application written to a popular PaaS, such as AppFog - In a modern dynamic scripting language, PHP - With a traditional relational database backend, MySQL - Should be a RESTful service - Application should use the best practices for object orientation and modularity for which language is chosen - Application should have unit tests that provide functional test coverage across the majority of the functionality - Source code should follow the popular coding style guidelines (e.g. pear coding standards)