Multi authorization with CodeIgniter
Facebook uses oAuth2Twitter uses oAuthStackOverflow uses OpenID.
Merging 3 entirely different protocols is not easy work, which is why no easy solution exists. You'll have to get your hands dirty for this sadly.
The closest you'll get is:
https://github.com/elliothaughin/socialize
That is not tested and I'm not sure if Elliot ever got around to finishing it.