This one is strange, its based on keeping one login through out multiple services.
Basically I have created a custom login system using "activecollab"s API to login, allowing the users in active collab to in effect have control over another site. In order to do this I have not found a single CMS or PHP Framework that allows this in any kind of simple form.
Basically how it works is the user tries to login and it sends the credentials to the activecollab API, then it will return a token. This will allow me to set a session and verify the user. Is there a way to do this in Joomla? Having the advanced CMS features of Joomla would make the rest of the development much easier, however trying various ways I ended up starting it without even using a framework, as none I could find allowed this without ignoring most of the built in functions.
If there is a way to use Joomla I would prefer too, is it possible to use a custom OAuth login rather then the normal Joomla user table? The administration panel does not matter, the main focus is front end login for custom controls.
EDIT: Might of forgotten a key part of this, the login should work regardless of the user being in the user table of Joomla, basically if a user has an account in the activecollab site, they should be able to log into the joomla site without ever needing to register.