Create change log entry on status updates

dav_events/models/eventchange.py

@@ -7,10 +7,6 @@ from django.utils.encoding import python_2_unicode_compatible
 
 from . import get_ghost_user, get_system_user
 
-CHANGE_OPERATIONS = (
-    ('update', 'update'),
-)
-
 
 def get_system_user_id():
     return get_system_user().id
@@ -18,6 +14,15 @@ def get_system_user_id():
 
 @python_2_unicode_compatible
 class EventChange(models.Model):
+    UPDATE = 'update'
+    RAISE_FLAG = 'set_flag'
+    LOWER_FLAG = 'unset_flag'
+    OPERATION_CHOICES = (
+        (UPDATE, 'Update'),
+        (RAISE_FLAG, 'Raise Flag'),
+        (LOWER_FLAG, 'Lower Flag'),
+    )
+
     event = models.ForeignKey('dav_events.Event', related_name='changes')
     timestamp = models.DateTimeField(default=timezone.now)
     user = models.ForeignKey(settings.AUTH_USER_MODEL,
@@ -25,7 +30,7 @@ class EventChange(models.Model):
                              on_delete=models.SET(get_ghost_user),
                              related_name='+')
 
-    operation = models.CharField(max_length=20, choices=CHANGE_OPERATIONS)
+    operation = models.CharField(max_length=20, choices=OPERATION_CHOICES)
     content = models.TextField()
 
     class Meta: