Feature? – water x inches per week

I assume open sprinkler does not support this feature. I’m trying to understand if anyone is working on it, or if it is even possible.

I’d like to build a schedule that ensures the lawn receives 1 inch per week of water. To work this would need to do a number of things:
– store a ‘flow’ value for each sprinkler in terms of inches per hour
– track the amount of rain over the past 7 days of scheduled run
– calculate the amount of water needed in current run based upon
— water gap = amount of water req’d – rain over last 7 days
— length of run = water gap / flow * zimmerman adjustment
– run time will be capped at a maximum run time (set per sprinkler)

breaking this down a bit (for each sprinkler) ..
unsigned long flow; // rate of water distributed by sprinkler as generic units / minute
unsigned long max_time; // max runtime in minutes of a sprinkler
unsigned long water_amt; // # units of water to deliver per period
unsigned long water_prd; // # days in the period

at this point, I’m not sure there is a mechanism that tracks how much water was provided over a time period…. opensprinkler doesn’t have a database does it? maybe I can do this from my Vera controller …

Anyone try this?