#974 Sort the header menu (#976)

* #974  Sort the top menu

* #974  Apply pdd rules

shopelectro/logic/__init__.py

@@ -0,0 +1,3 @@
+from . import header
+
+__all__ = ['header']

shopelectro/logic/header.py

@@ -0,0 +1,24 @@
+from django.conf import settings
+from django.db.models import Q
+
+from pages import models as pages_models
+from shopelectro import models
+
+
+def menu_qs() -> pages_models.PageQuerySet:
+    return (
+        pages_models.Page.objects.active()
+        .filter(
+            Q(slug__in=settings.HEADER_LINKS['add'])
+            & ~Q(slug__in=settings.HEADER_LINKS['exclude'])
+            | (
+                # @todo #974:30m  Optimize the header menu query.
+                #  Fetch catalog page for the header menu at the same query.
+                #  root category pages.
+                Q(parent=pages_models.CustomPage.objects.filter(slug='catalog'))
+                & Q(related_model_name=models.Category._meta.db_table)
+                & Q(parent=pages_models.CustomPage.objects.filter(slug='catalog'))
+            )
+        )
+        .order_by('position')
+    )

shopelectro/templatetags/se_extras.py

@@ -10,14 +10,15 @@
 
 from images.models import ImageMixin
 from pages.models import Page
-
 from shopelectro.models import CategoryPage
 
 register = template.Library()
 
 
 @register.simple_tag
 def roots():
+    # @todo #974:60m  Reuse the logic.header.menu_qs menu menu query.
+    #  And test HEADER_LINKS "exclude/add" settings option.
     return sorted(
         chain(
             Page.objects.filter(slug__in=settings.HEADER_LINKS['add']),

shopelectro/tests/tests_logic.py

@@ -0,0 +1,14 @@
+from django.test import TestCase, override_settings, tag
+
+from shopelectro import models, logic
+
+
+@tag('fast')
+@override_settings(HEADER_LINKS={'exclude': [], 'add': []})
+class HeaderMenu(TestCase):
+    fixtures = ['dump.json']
+
+    def test_roots_are_presented(self):
+        from_db = set(models.CategoryPage.objects.get_cached_trees())
+        from_logic = set(logic.header.menu_qs())
+        self.assertEqual(from_db, from_logic)