Automating mockup creation using AppleScript

[gwk0]

How do I create a new file from a mockup template using AppleScript?

Is there a special way to target the media placeholder to replace the image?

Context:

I would like to create a script that will accept a folder of image files, then for each file create a new document from the mockup template I want to use, then replace the placeholder image with the current one and save it in a different folder with the filename of the image.