I may have an answer for you.
IMHO I believe he is a blue Indian ring neck parrot. A common domesticated species.
Google him for more info.
If he is still around, try feeding him, he may be hungry if he hasn't been in the wild for long.
Actually after re-assesing, I believe the beak to be too light in colour for a ring neck... Maybe the light.
This has me puzzled...
