Custom image editor for Google Docs

Question

I am designing a web application that as an end result creates images (graphs plots, etc). These images will get used in Google docs documents. Users also need to be able to edit these images after they already posted to Google docs.

In the current version, I add a link around the image with the url to the location of my Flash editor, and allow the user to edit it, but I would like to offer the user inline editing, possibly using JavaScript and/or Flash. (Something Similar to Google's existing drawing editor)

I am looking to see if anyone has embedded JavaScript or Flash into a Google Doc or added any extensions like this.

Thanks