Add the Event.visibility field

This shows if the event is visible to anyone or just people who are invited.

The calendar view already respects this flag.

calsocial/calendar_system/gregorian.py

@@ -199,12 +199,14 @@ class GregorianCalendar(CalendarSystem):
         """Returns all events for a given day
         """
 
-        from ..models import Event, Profile
+        from ..models import Event, EventVisibility, Invitation, Profile, Response
 
         events = Event.query
 
         if user:
-            events = events.join(Profile) \
+            events = events.outerjoin(Invitation) \
+                           .outerjoin(Response) \
+                           .join(Profile, Event.profile) \
                            .filter(Profile.user == user)
 
         start_timestamp = date.replace(hour=0, minute=0, second=0, microsecond=0)
@@ -216,4 +218,12 @@ class GregorianCalendar(CalendarSystem):
                                 (Event.end_time < end_timestamp))) \
                        .order_by('start_time', 'end_time')
 
+        if user is None:
+            events = events.filter(Event.visibility == EventVisibility.public)
+        else:
+            events = events.filter((Event.visibility == EventVisibility.public) |
+                                   (Event.profile == user.profile) |
+                                   (Invitation.invitee == user.profile) |
+                                   (Response.profile == user.profile))
+
         return events