Indeed a beautiful huntsman spider! But it's not Palystes castaneus, they're only found in South Africa. We call them rain spiders. As far as I know, there aren't Palystes sp. spiders in Indonesia, which makes this very interesting because this one you've found looks very much like one. It might belong to the genus Heteropoda, but I'm not certain.
And this is one is a lovely lady, haha. She probably has an egg sac nearby or will soon be ready to make one.