A redstone door with a password(1,2,2-must be in that order).
The Redstone lamps in the right side(of the screenShot(its out side of it)is the unfinished part and if you getting closed inside you cant go out(only with a teleportaion or a command) and the radstone lams should view the numbers that was clicked(only 3) and after 3 clicks the click wont pass signals at all

if someone want to complete it or upgrade it i would be very happy