Caravan sites Croatia

I would like to visit Croatia, has anyone had any experience of good sites there.  My requirements are electricity, car by caravan, decent size pitch, good facilities.  I would be going before mid July or from the end of August staying about 1 month there.  I would like to stay in 2 or 3 places working my way down the coast but not as far as Dubrovnik.  It would be nice to be able to walk into smaller harbour towns.

Any help appreciated