Hope you can help. First post, so hopefully I have this in the right section and follow the guidelines. Be gentle with me! 
The Crosswater bath filler has no IoT integration and just has a basic web interface over a few pages. I am not looking for detailed control, but the “Fill Bath” is probably the only useful capability… as draining is simple enough as you are in the bath then! So effectively I am just needing a method to simply press a single button on a web page, hopefully someone can guide me to the best way of achieving this in HA.
It may be possible using some plugin to “virtually push” the button or it may just be easy to spam a command to the controller to do the same.
Assuming the latter is possible the frame code for the page at:
http://ip_address/#/1/quick_bath_fill
is on this pastebin link with the section of interest around line 94:
<div class="bath-button ng-binding" id="button-1" data-ng-click="startBathtubFill(quickTemp1, quickAmount1, 1)" style="background-color: rgb(155, 155, 155); cursor: pointer;">Fill bathtub</div>
This seems to have a handy function to fill a bath to a certain temperature and volume. But how can I co-opt it? Is it possible?
Looking at my query, what do the experienced hands think is the best approach to try and integrate this to HA?
Used pastebin as it will format HTML a little nicer and who wants to see 200 lines of HTML here!?
Thanks all,
Alex