Who become hogwarts headmaster after snape?

Initially, after the death of Prof Dumbledore, it was supposed to be Prof Minerva McGonagall since she is second in command at Hogwarts, but due to power struggle at the Ministry, thus Prof Snape had become a headmaster (but this was also planned by Albus) to have a spy with-in Hogwarts who is in league with him even at his death, after the Battle at Hogwarts, Minerva McGonagall was proclaimed Headmistress and began her era as Headmistress of Hogwarts.