A reference design for a custom use-case? Not so much. Enter the ESP32 microcontroller (MCU), a low cost and easily programmable (with the Arudino IDE at least) MCU with built-in WiFi and many other features. You can easily find a module with user-friendly pinouts for under ten bucks online!
The module used is kind of an overkill, but that is how cheap such things have gotten over time.
I gave a talk about the process, at the Hackware 3.7 event in Singapore back in 2017.
Hardware: CAD, 3D printing