The payment flow for embedding videos is the same as on https://videos.l402.org
The app detects the L402:// URI, fetches the service details, checks for valid credentials, and either plays the video or prompts for payment. After payment, the credentials are used to access the video.
You can check the blockbuster (server) and blockbuster-video-demo repos for more details. If anything is unclear, feel free to open an issue and we will fix it ASAP!