How to randomize a video sequence

I want to randomize a movie sequence by letting the code randomly choose which shots to play in a sequence. Let's say i want to play a sequence of 10 shots and each shot has 3 or 4 almost identical takes labled a-d, so the code would upon refresh randomize the sequence as 1B, 2C, 3A, 4A, 5B, 6A, 7D... and so on, but key here is that each time it would be a unique movie and that it would play SEAMLESSLY. Also key is that the shot order should NOT be randomized.

I'm thinking this could be a simple html5 video player on a website. I am a total beginner when it comes to coding, but I am looking to find a simple code that I could copy and tweak to get started. Thankful for any help!

example