Arduino as a power supply controller


I was thinking of installing a power monitoring/distributing system for my boat. It would consist of: 1) An array of lithium ion cells (a la 18650 cells in series/parallel) and charging circuitry; 2) A solar panel array; 3) switchability when engine alternator power is available and for priority switching of power for different loads (i.e. Pumps, peltier coolers, lighting, small inverter, etc)....
Is anyone aware of any such beast that is already available?