[Refactor] Move invitation code to the Event model

calsocial/__init__.py

@@ -255,7 +255,7 @@ class CalendarSocialApp(Flask):
         """
 
         from .forms import InviteForm
-        from .models import db, Event, Invitation, Notification, NotificationAction
+        from .models import db, Event
 
         try:
             event = Event.query.filter(Event.event_uuid == event_uuid).one()
@@ -267,15 +267,7 @@ class CalendarSocialApp(Flask):
         form = InviteForm(event)
 
         if form.validate_on_submit():
-            invite = Invitation(event=event, sender=current_user.profile)
-            form.populate_obj(invite)
-            db.session.add(invite)
-
-            notification = Notification(profile=form.invitee.data,
-                                        actor=current_user.profile,
-                                        item=event,
-                                        action=NotificationAction.invite)
-            db.session.add(notification)
+            event.invite(current_user.profile, invitee=form.invitee.data)
 
             db.session.commit()