Use sorcery for logins

This gives us more flexibility and allows us to use password authentication
later. Also we don't need to build the login functionality ourself.

app/models/authentication.rb

@@ -1,6 +1,8 @@
 class Authentication < ApplicationRecord
   belongs_to :user
 
+  scope :for, -> (provider) { where(provider: provider) }
+
   encrypts :access_token
   encrypts :refresh_token
 
@@ -9,6 +11,7 @@ class Authentication < ApplicationRecord
   end
 
   def google_authorization
+    return nil unless provider == 'google'
     @google_authorization ||= CLIENT_SECRETS.to_authorization.tap do |c|
       c.access_token = self.access_token
       c.refresh_token = self.refresh_token

app/models/user.rb

@@ -1,40 +1,18 @@
 class User < ApplicationRecord
+  authenticates_with_sorcery!
   has_many :authentications, dependent: :destroy
   has_many :forms, dependent: :destroy
 
-  def self.find_by_oauth_info(auth_client)
-    oauth = Google::Apis::Oauth2V2::Oauth2Service.new
-    oauth.authorization = auth_client
-    user_info = oauth.get_userinfo
-
-    if user = User.find_by(google_id: user_info.id)
-      authentication = user.authentications.last
-      authentication.access_token = auth_client.access_token if auth_client.access_token.present?
-      authentication.refresh_token = auth_client.refresh_token if auth_client.refresh_token.present?
-      authentication.expires_at = Time.at(auth_client.expires_at) if auth_client.expires_at.present?
-      authentication.save
-      return user, authentication
-    else
-      user = User.create(name: user_info.name, email: user_info.email, google_id: user_info.id)
-      authentication = user.authentications.create(
-        access_token: auth_client.access_token,
-        refresh_token: auth_client.refresh_token,
-        expires_at: Time.at(auth_client.expires_at)
-      )
-      return user, authentication
-    end
-  end
-
   def deactivate!(reason = nil)
     # currently we only use deactivate if we get an authentication exception appending data to a spreadsheet
     authentications.last&.update(expires_at: Time.current)
   end
 
   def active?
-    authentications.last.present? && !authentications.last.expired?
+    authentications.any? { |a| !a.expired? }
   end
 
   def google_authorization
-    authentications.last.google_authorization
+    authentications.for(:google).last.google_authorization
   end
 end