Start here:
An application to control pool equipment from various manufacturers. - tagyoureit/nodejs-poolController
github.com
It’s incredibly easy to set up. I am not sure about the solar settings, I might need to double check that.
It also has a HomeAssistant integration if you use that stuff as well.
The most expensive component is probably the box you mount it in. Altelix makes the best ones. Make sure you get a Din Rail one.
I am on my 3rd rebuild and can do it pretty quickly now if you need help. I am probably about 45 min down the road from you.