I'm trying to do a Difference in Difference estimate with clusters and staggering events.

I have information on counties across four different states, and each county implemented the treatment on different days throughout one year.

Ideally, I'd like to have clusters by states, so four clusters, and be able to account for the different times in which the treatment went into effect in the treatment counties. Does anyone have any ideas or suggestions on how I could run this DiD estimate.