I had a homemade setup in my van that I need to replace and would like to
improve.  I had a switch in the van mounted down near the outlet by the
bed.  In one position it connected all the AC outlets to shore power.  In
the other it connected them all to an inverter and turned the inverter on.
I relied on discipline to not switch it to the inverter position when
plugged into shore power.  That aspect of the system was obviously far from
ideal.  If I wanted to use a charger, I would plug it in manually and
connect it to the aux battery and again, make sure I did not have the
switch in the "inverter position."

So what I would like is:
-A system that would start charging the aux battery when I was plugged into
shore power.  2 Amp maximum power is fine.
-When not plugged into shore power I would have the option to power all AC
outlets from inverter.  Inverter capacity of 400W should be fine.
-Not blow up or cause damage if I accidentally turn on the inverter when
plugged into shore power.

Is there a commercially available device to do this?  I hear you volks talk
about using some "surepower" device or something like that?

Thanks,
Edward