I don't see any reason why Messi will leave Barcelona, he love for the team is extraordinary.
Basically, he has a reason. He should think to play in another club once he is in the top performance. There are many players who leave the club before retiring. At least, there is an experience to play in another club, it should be very different and requires a challenge. As a professional player, I am sure Messi considers leaving Barcelona before he decides to retire.
it seems PSG have an eye on the star player, but Messi is not giving them any positive respond.
For now, there is no strong rumor that Messi probably moves to PSG.
Well, I think Messi will stay in Barcelona. Moreover, he has Aguero now.