Actually, this will be done more or less automatically if I do not do anything, except that the shutdown will be hard when the power will be turned off.
A lot of BIOS have settings for things like "boot at power on". You could shut down normally, then have an external timer that turns the power on. That should keep everything clean.
Yes, I have the boot at power on set. I can shut down, But does it means that it will boot when the power will be back? I do not have a timer under my control. It has to be automatic (of course I could say restart at 12:00, but I have to say it at the shutdown)