I was wondering if this was already built somewhere or if I had to write a custom one?

Image shows what I want to do to zenphoto:
http://teamfod.com/gallery/VAPOR/zenphoto_bbcode.png

It will add sharing codes for each image, direct link, bbcode, markdown and html.

The link does not work btw. All extensions known to us are listed on the extensions section.

Sorry here you go - http://teamfod.com/images/zenphoto_bbcode.png

I know what mods you have but HOW can I create a mod to do this?

Well, you would have to write a plugin. You would have to take the current url and add the wrappers. We have tutorials for that and also example files:
http://www.zenphoto.org/news/category/development/

Cool, thank you...just what I needed.