Nextcloud/webdav authentication

I was wondering how difficult it would be to authenticate users against a nextcloud/webdav instance?
Our instance doesn’t use ldap and switching now would be a lot of effort with some disadvantages so I’d like to keep it that way but make my jitsi instance available only to registered users of my nextcloud instance.

If it’s possible to generate a token for the authenticated user on the Nextcloud side, Jitsi with a JWT authentication will work

I guess it’s possible if you write an App for it but so far that has not been done.
But there is an XMPP app that authenticates with nextcloud and I think it might be possible to connect to that.

I’m not up to my game with prosody but there is JSXC that authenticates against nextcloud and can use prosody and some similar things but I’m not sure how to integrate into those with the prosody from jitsi.
I was hoping someone had already tried that or would be interested in doing it.