i work in a kindergarten and a kid has started to hit me, i have tried everything from immediately asserting that i am "in charge" telling it NOT ever to do that, ive tried the "hugging" method where you use your size to "restrain" the child without actually, you know, hurting the child in any way what so ever, ive also tried the "you do something i dont want you to do, i leave/ isolate you from what we are currently doing" methods

its a good kid, we have some good times but later in the day i am not able to project authority on this kid, on the good days its a bright kid, who is good at playing and communication. this kid often comes to me if something is wrong (like the pissed the pants, some other kid hit them, or they fell or something)
but, still, this kid will hit me and smile/laugh, its cause he wants to engage with me, one on one, but proffesionally that is just not possible in the way he craves so he sought the most extreme way to get my attention.

what do?