Best way to handle looping increasing counter

Setup, Configuration and Use Scripts & Rules
2

Just to make sure I understand, the sensor counts up over days until the max is exceeded and then it starts over. It doesn’t reset under any other circumstances (time, power loss, etc.), correct?

I once wrote a rule template to handle something similar to this but unfortunately it’s not one that I rewroite for OH 4. It’s been on my list but no one really used it so it’s never been a priority, and there is another rule template that does mostly the same thing only better.

Both are focused on energy reading but the same approach applies here I think. You’ll need a proxy Item for tracking the daily rainfall.

  1. At a high level trigger the rule on changes to the sensor Item.
  2. If the current state is > the previous state
    a. Add the difference between the previous state and the current state tracking Item
  3. else
    b. Add the new value to the current state tracking Item

At midnight trigger a rule to reset the tracking Item to 0, or just let it continue to increase forever. Unless your name is Noah you are unlikely to see enough rain over a lifetime to exceed the maximum value allowed. I’m not sure which will work best for your evolution calculation. I think resetting would still work except between midnight and 1 am perhaps so maybe that needs a work around if you reset it.

This will essentially eliminate that rollover (the following assumes a managed rule and JS Scripting and UoM).

var currReading = Quantity(event.itemState);
var prevReading = Quantity(event.oldItemState);
var total = items.ProxyItem.quantityState;

if(currReading.lessThan(prevReading)) {
    total = total.add(currReading);
} else {
    const delta = currReading.minus(prevReading);
    total = total.add(delta);
}

items.ProxyItem.postUpdate(total);

You will use ProxyItem in your current rule.

Other notes, time.toZDT() can make your time code a lot simpler:

const minus_1h = time.toZDT('PT-1H'); // ISO8601 duration string
const start_of_day = time.toZDT('00:00'); // supports AM/PM as well as 24 hour time strings

If you keep the now.withHour(.... approach make sure to add withMillis(0) or else you could be off of exactly midnight by almost a second.