event: Rework initialization process

While fixing timezone bugs, it was found that the calendar property needs
to be set before the component property. The component times may require
to have the calendar set, to be able to lookup the custom timezones in the
calendar, thus make sure the calendar is set before the component is set,
during the construction time.

Rework the initialization process so that setting the construct-only
component property merely takes a hold on the references; and the actual
setting up of the event happens during g_initable_init().

Closes https://gitlab.gnome.org/GNOME/gnome-calendar/-/issues/788

src/core/gcal-event.c

@@ -103,9 +103,6 @@ struct _GcalEvent
   GcalCalendar       *calendar;
 
   GcalRecurrence     *recurrence;
-
-  gboolean            is_valid : 1;
-  GError             *initialization_error;
 };
 
 static void          gcal_event_initable_iface_init              (GInitableIface *iface);
@@ -118,13 +115,13 @@ G_DEFINE_QUARK (GcalEvent, gcal_event_error);
 enum {
   PROP_0,
   PROP_ALL_DAY,
+  PROP_CALENDAR,
   PROP_COLOR,
   PROP_COMPONENT,
   PROP_DESCRIPTION,
   PROP_DATE_END,
   PROP_DATE_START,
   PROP_LOCATION,
-  PROP_CALENDAR,
   PROP_RANGE,
   PROP_SUMMARY,
   PROP_TIMEZONE,
@@ -309,9 +306,9 @@ load_alarms (GcalEvent *self)
   g_slist_free_full (alarm_uids, g_free);
 }
 
-static void
+static gboolean
-gcal_event_set_component_internal (GcalEvent     *self,
+setup_component (GcalEvent  *self,
-                                   ECalComponent *component)
+                 GError    **error)
 {
   g_autoptr (GTimeZone) zone_start = NULL;
   g_autoptr (GTimeZone) zone_end = NULL;
@@ -324,12 +321,10 @@ gcal_event_set_component_internal (GcalEvent     *self,
   gboolean start_is_all_day, end_is_all_day;
   gchar *description, *location;
 
-  g_assert (self->component == NULL);
+  g_assert (self->component != NULL);
-
-  self->component = e_cal_component_clone (component);
 
   /* Setup start date */
-  start = e_cal_component_get_dtstart (component);
+  start = e_cal_component_get_dtstart (self->component);
 
   /*
    * A NULL start date is invalid. We set something bogus to proceed, and make
@@ -337,14 +332,15 @@ gcal_event_set_component_internal (GcalEvent     *self,
    */
   if (!start || !e_cal_component_datetime_get_value (start))
     {
-      self->is_valid = FALSE;
+      g_set_error (error,
-      g_set_error (&self->initialization_error,
                    GCAL_EVENT_ERROR,
                    GCAL_EVENT_ERROR_INVALID_START_DATE,
                    "Event '%s' has an invalid start date", gcal_event_get_uid (self));
 
       e_cal_component_datetime_free (start);
       start = e_cal_component_datetime_new_take (i_cal_time_new_today (), NULL);
+      g_clear_pointer (&start, e_cal_component_datetime_free);
+      return FALSE;
     }
 
   GCAL_TRACE_MSG ("Retrieving start timezone");
@@ -365,7 +361,7 @@ gcal_event_set_component_internal (GcalEvent     *self,
   g_clear_object (&date);
 
   /* Setup end date */
-  end = e_cal_component_get_dtend (component);
+  end = e_cal_component_get_dtend (self->component);
 
   if (!end || !e_cal_component_datetime_get_value (end))
     {
@@ -395,35 +391,34 @@ gcal_event_set_component_internal (GcalEvent     *self,
     }
 
   /* Summary */
-  text = e_cal_component_get_summary (component);
+  text = e_cal_component_get_summary (self->component);
   if (text && e_cal_component_text_get_value (text))
     gcal_event_set_summary (self, e_cal_component_text_get_value (text));
   else
     gcal_event_set_summary (self, "");
 
   /* Location */
-  location = e_cal_component_get_location (component);
+  location = e_cal_component_get_location (self->component);
   gcal_event_set_location (self, location ? location : "");
 
   /* Setup description */
-  description = get_desc_from_component (component, "\n\n");
+  description = get_desc_from_component (self->component, "\n\n");
   gcal_event_set_description (self, description);
 
   /* Setup UID */
   gcal_event_update_uid_internal (self);
 
   /* Set has-recurrence to check if the component has recurrence or not */
-  self->has_recurrence = e_cal_component_has_recurrences(component);
+  self->has_recurrence = e_cal_component_has_recurrences(self->component);
 
   /* Load the recurrence-rules in GcalRecurrence struct */
-  self->recurrence = gcal_recurrence_parse_recurrence_rules (component);
+  self->recurrence = gcal_recurrence_parse_recurrence_rules (self->component);
 
   /* Load and setup the alarms */
   load_alarms (self);
 
   g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_HAS_RECURRENCE]);
   g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_RECURRENCE]);
-  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_COMPONENT]);
 
   g_clear_pointer (&description, g_free);
   g_clear_pointer (&location, g_free);
@@ -431,31 +426,32 @@ gcal_event_set_component_internal (GcalEvent     *self,
   e_cal_component_text_free (text);
   e_cal_component_datetime_free (start);
   e_cal_component_datetime_free (end);
+
+  return TRUE;
+}
+
+
+static void
+gcal_event_set_component_internal (GcalEvent     *self,
+                                   ECalComponent *component)
+{
+  g_assert (self->component == NULL);
+  self->component = e_cal_component_clone (component);
+  g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_COMPONENT]);
 }
 
 /*
  * GInitable iface implementation
  */
 
-G_LOCK_DEFINE_STATIC (init_lock);
-
 static gboolean
 gcal_event_initable_init (GInitable     *initable,
                           GCancellable  *cancellable,
                           GError       **error)
 {
-  GcalEvent *self;
+  GcalEvent *self = GCAL_EVENT (initable);
 
-  self = GCAL_EVENT (initable);
+  return setup_component (self, error);
-
-  G_LOCK (init_lock);
-
-  if (!self->is_valid)
-    g_propagate_error (error, g_error_copy (self->initialization_error));
-
-  G_UNLOCK (init_lock);
-
-  return self->is_valid;
 }
 
 static void
@@ -785,8 +781,6 @@ gcal_event_init (GcalEvent *self)
 
   /* Alarms */
   self->alarms = g_hash_table_new_full (g_direct_hash, g_direct_equal, NULL, g_free);
-
-  self->is_valid = TRUE;
 }
 
 /**
@@ -1393,7 +1387,8 @@ gcal_event_set_calendar (GcalEvent    *self,
 
       g_object_notify_by_pspec (G_OBJECT (self), properties[PROP_CALENDAR]);
 
-      gcal_event_update_uid_internal (self);
+      if (self->component != NULL)
+        gcal_event_update_uid_internal (self);
     }
 }