PDF Invoice Generator - PHP & Yii Framework

Our company has written a flexible custom billing system on top of the Yii Framework [login to view URL] which now requires a module that can generate printable invoices in PDF format. We need a programmer who is well versed in using the Yii Framework and is an expert in strict object-oriented programming with PHP to develop our printable PDF module. You will be provided with a set of example code and unit tests which you can use to verify the functionality of your module, as well as UML diagrams and details from our programmers as to the methods that must be handled by your code. Your code should be able to drop right in to our production application and function without issue. The purpose of the module that we require is to generate printable invoices in a particular format (an example invoice PDF will be provided). The project must use the TCPDF library, which is already in use elsewhere in our Yii Framework-based application. Please provide brief details of examples of your experience with Yii Framework or another strict OOP framework for PHP in your bid. You must know how to produce quality code with working unit tests; experience with TCPDF is a plus. Please review the attached technical documentation PDF before bidding so that you can get an idea of the functionality that we require as well as the information and samples that will be provided to you.