Required activity: Assignment with file submission

1. A student submits a file.
2. Status changes to "Submitted for grading"
3. Student clicks on "Edit submission" and deletes submission.
4. Student clicks on "Save changes"
5. Error occurs: "Nothing was submitted"

So far this is the normal behavior. The issue is this:

6. The student closes the site or clicks on "cancel"
7. Result: There is no file submitted, but the status is still "Submitted for grading"

This can be a problem. The student should not be allowed to delete the submitted file without uploading a new one. The problem seems to occur because moodle handles the uploading and deleting of files in real time. Once the user deletes the file in the file picker it's gone. Maybe this issue could be resolved by improving the user experience by warning the user that deletion of the file is permanent.