Prevent editing shipped lines on sales order. Account for editing a split line.

Summary:

When we moved to Oracle, a consultant helped write a Groovy Script to prevent editing if a line was already on a shipment. It seems to no longer work, especially with Split Lines.

Content (required):

This is the script they wrote for us. I need help modifying it so when there is a split line that's partially shipped, the error is thrown and they cannot ship.

I thought maybe I could figure it out by modifying to loop through FulfillLineDetails, but that didn't seem to work, or I did it wrong.

Attached is the area I tried modifying

I am not an expert in OM, I have Java and JavaScript experience, but wasn't able to find much helpful documentation on what's available to help accomplish the goals that were given.