From 059a3b95c2736c60acfafd686908372be4567b16 Mon Sep 17 00:00:00 2001
From: Valentin Deniaud <vdeniaud@entrouvert.com>
Date: Thu, 11 Mar 2021 12:00:43 +0100
Subject: [PATCH 1/2] manager: use slug instead of start_datetime to identify
 event recurrence (#51778)

---
 chrono/agendas/models.py | 11 +++++++++--
 chrono/manager/forms.py  |  5 +----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/chrono/agendas/models.py b/chrono/agendas/models.py
index 8e06bac..e6246c4 100644
--- a/chrono/agendas/models.py
+++ b/chrono/agendas/models.py
@@ -594,7 +594,7 @@ class Agenda(models.Model):
         excluded_datetimes = collections.defaultdict(list)
         for event in events:
             if event.primary_event_id:
-                excluded_datetimes[event.primary_event_id].append(make_naive(event.start_datetime))
+                excluded_datetimes[event.primary_event_id].append(event.datetime_slug)
 
         events = [
             e for e in events if (not e.cancelled or include_cancelled) and (not e.full or include_full)
@@ -641,7 +641,7 @@ class Agenda(models.Model):
         report.events.set(events)
 
         # add recurrences
-        excluded_datetimes = [make_naive(dt) for dt in recurrences.values_list('start_datetime', flat=True)]
+        excluded_datetimes = [event.datetime_slug for event in recurrences]
         Event.create_events_recurrences(
             recurring_events.filter(recurrence_end_date__isnull=False), excluded_datetimes
         )
@@ -1487,6 +1487,13 @@ class Event(models.Model):
             )
         Event.objects.bulk_create(recurrences)
 
+    @property
+    def datetime_slug(self):
+        assert self.primary_event is not None, 'only for event recurrence'
+
+        datetime_part = self.slug.rsplit('--')[-1]
+        return datetime.datetime.strptime(datetime_part, '%Y-%m-%d-%H%M')
+
 
 class BookingColor(models.Model):
     COLOR_COUNT = 8
diff --git a/chrono/manager/forms.py b/chrono/manager/forms.py
index 9017164..dcf36a1 100644
--- a/chrono/manager/forms.py
+++ b/chrono/manager/forms.py
@@ -238,10 +238,7 @@ class EventForm(forms.ModelForm):
                 self.instance.recurrences.filter(
                     start_datetime__gt=self.instance.recurrence_end_date
                 ).delete()
-                excluded_datetimes = [
-                    make_naive(dt)
-                    for dt in self.instance.recurrences.values_list('start_datetime', flat=True)
-                ]
+                excluded_datetimes = [event.datetime_slug for event in self.instance.recurrences.all()]
                 self.instance.create_all_recurrences(excluded_datetimes)
         return self.instance
 
-- 
2.20.1