Save progress in video course

Hello.
I want to create a video course with the following rules:
1. it is possible to scroll the progress of only the studied part of the video - this means that the user can scroll the part of the video that he has already seen, but he cannot skip the content that he has not seen.
I know about the seekbar "read only"/"allow drag after competition" options, but it is not enough. I was thinking to somehow cover the video controls (switched on in video options menu) with transparent rectangles and use variables to reveal these rectangles step by step.
Do you think it is worth the effort? This idea seems to need a lot of work. Is there a simpler way to do it?

2. the video progress is sent to the LMS. If a user exits a video course and turns it on later, the video will continue playing where it left off.
Thank you for any advice. Andrea