Tidy up the logic checks and remove the frozen property

src/wagtail_personalisation/forms.py

@@ -10,6 +10,7 @@ from django.core.exceptions import ValidationError
 from django.test.client import RequestFactory
 from django.utils import timezone
 from django.utils.lru_cache import lru_cache
+from django.utils.translation import ugettext_lazy as _
 from wagtail.wagtailadmin.forms import WagtailAdminModelForm
 
 
@@ -30,39 +31,39 @@ def user_from_data(user_id):
 class SegmentAdminForm(WagtailAdminModelForm):
     def clean(self):
         cleaned_data = super(SegmentAdminForm, self).clean()
+        Segment = self._meta.model
 
-        rules = [form for formset in self.formsets.values() for form in formset if form not in formset.deleted_forms]
-        consistent = rules and all(rule.instance.static for rule in rules)
+        rules = [
+            form.instance for formset in self.formsets.values()
+            for form in formset
+            if form not in formset.deleted_forms
+        ]
+        consistent = rules and Segment.all_static(rules)
 
-        from .models import Segment
         if cleaned_data.get('type') == Segment.TYPE_STATIC and not cleaned_data.get('count') and not consistent:
-            raise ValidationError({
-                'count': ('Static segments with non-static compatible rules must include a count.'),
-            })
+            self.add_error('count', _('Static segments with non-static compatible rules must include a count.'))
 
         return cleaned_data
 
     def save(self, *args, **kwargs):
+        is_new = not self.instance.id
+
         instance = super(SegmentAdminForm, self).save(*args, **kwargs)
 
-        if instance.can_populate:
+        if is_new and instance.is_static and instance.all_rules_static:
             from .adapters import get_segment_adapter
 
             request = RequestFactory().get('/')
             request.session = SessionStore()
             adapter = get_segment_adapter(request)
 
-            rules = [rule for rule in instance.get_rules() if rule.static]
-
             for session in Session.objects.filter(expire_date__gt=timezone.now()).iterator():
                 session_data = session.get_decoded()
                 user = user_from_data(session_data.get('_auth_id'))
                 request.user = user
                 request.session = SessionStore(session_key=session.session_key)
-                passes = adapter._test_rules(rules, request, instance.match_any)
+                passes = adapter._test_rules(instance.get_rules(), request, instance.match_any)
                 if passes:
                     instance.sessions.add(session)
 
-        instance.frozen = True
-        instance.save()
         return instance