Product question - external camera / light (replacing existing stand-alone light)

We are looking to replace our existing backyard light, with a camera and light. But there is something I am not understanding and need to clarify, before I go out and buy it. Right now, the light turns on and off, via a switch we have inside. If I do a straight replacement, if we turn off the switch to turn off the light, then camera won't have power. If we leave the switch on, then the lights are on all the time as well, which is both wasteful, and could be bothersome to neighboors. I only have 1 circuit/connection, between the switch and the current outside light. These are my questions: 1 - how exactly do we do it, that the camera always has power, but that we be able to turn the lights on and off (like if we are cooking or something)? 1B - Are the camera and lights powered independantly (as in same or separate wires). If separate, wires then I can get an electrician to run separate power just for the camera 2 - Do the lights (also) turn on automatically by motion? 3 - If the wired camera has night vision, does it automatically turn on the lights to film? Thank you all in advance.