How to use Facebook OAuth with Ember Simple Auth?

I have an Ember.js app using Ember Simple Auth. The API returns an auth token on successful sign in with email and password. I'm trying to add Facebook Login using their Javascript SDK. Upon successful sign in with Facebook, I would like to post the Facebook access token back to our API, so that the API can store the access token and respond with our own auth token. However, I'm not sure how to connect this to Ember Simple Auth so that the auth token can be stored outside of the normal email/password sign in. What do I need to do in order to make this work?