How to Stamp the Unique Filename

Question

I receive some PDF's via email, i need unique filename is stamped onto the pdf before send to customer. how to do this?

Launching the application: A-PDF Watermark
In the main window, clicking "add text watermark" icon, then will open the New Text Watermark configuration window, you can set the Macro value here, the macro is to specify dynamic text, such as "%Filename%"
Return to the main window, clicking "File" menu, then select "Add PDF Document" item, Add PDF(s) which you want to add watermark
In the watermark list window, marking the text-macro watermark item as checked
Clicking "Watermark" button to add the text-macro watermark