From 36834835cd155cd80778df4442e7b67499ed5abb Mon Sep 17 00:00:00 2001
From: Anatoly <a.feteleu@spider.ru>
Date: Fri, 20 Dec 2019 11:05:02 +0300
Subject: [PATCH] added filters to location views

---
 apps/location/filters.py    | 31 +++++++++++++++++++++++++++++++
 apps/location/models.py     | 22 ++++++++++++++++++++++
 apps/location/views/back.py |  7 ++-----
 3 files changed, 55 insertions(+), 5 deletions(-)

diff --git a/apps/location/filters.py b/apps/location/filters.py
index 5e95db44..c50b9964 100644
--- a/apps/location/filters.py
+++ b/apps/location/filters.py
@@ -22,3 +22,34 @@ class CityBackFilter(filters.FilterSet):
         if value not in EMPTY_VALUES:
             return queryset.search_by_name(value)
         return queryset
+
+
+class RegionFilter(filters.FilterSet):
+    """Region filter set."""
+
+    country_id = filters.CharFilter()
+    sub_regions_by_region_id = filters.CharFilter(method='by_region')
+    without_parent_region = filters.BooleanFilter(method='by_parent_region')
+
+    class Meta:
+        """Meta class."""
+        model = models.Region
+        fields = (
+            'country_id',
+            'sub_regions_by_region_id',
+            'without_parent_region',
+        )
+
+    def by_region(self, queryset, name, value):
+        """Search regions by sub region id."""
+        if value not in EMPTY_VALUES:
+            return queryset.sub_regions_by_region_id(value)
+
+    def by_parent_region(self, queryset, name, value):
+        """
+        Search if region instance has a parent region..
+        If True then show only Regions
+        Otherwise show only Sub regions.
+        """
+        if value not in EMPTY_VALUES:
+            return queryset.without_parent_region(value)
diff --git a/apps/location/models.py b/apps/location/models.py
index dc7834c9..be26e2c7 100644
--- a/apps/location/models.py
+++ b/apps/location/models.py
@@ -70,6 +70,26 @@ class Country(TranslatedFieldsMixin, SVGImageMixin, ProjectBaseMixin):
         return str_name
 
 
+class RegionQuerySet(models.QuerySet):
+    """QuerySet for model Region."""
+
+    def without_parent_region(self, switcher: bool = True):
+        """Filter regions by parent region."""
+        return self.filter(parent_region__isnull=switcher)
+
+    def by_region_id(self, region_id):
+        """Filter regions by region id."""
+        return self.filter(id=region_id)
+
+    def by_sub_region_id(self, sub_region_id):
+        """Filter sub regions by sub region id."""
+        return self.filter(parent_region_id=sub_region_id)
+
+    def sub_regions_by_region_id(self, region_id):
+        """Filter regions by sub region id."""
+        return self.filter(parent_region_id=region_id)
+
+
 class Region(models.Model):
     """Region model."""
 
@@ -82,6 +102,8 @@ class Region(models.Model):
         Country, verbose_name=_('country'), on_delete=models.CASCADE)
     old_id = models.IntegerField(null=True, blank=True, default=None)
 
+    objects = RegionQuerySet.as_manager()
+
     class Meta:
         """Meta class."""
 
diff --git a/apps/location/views/back.py b/apps/location/views/back.py
index 5dcb55bf..e306bc6e 100644
--- a/apps/location/views/back.py
+++ b/apps/location/views/back.py
@@ -1,5 +1,4 @@
 """Location app views."""
-from django_filters.rest_framework import DjangoFilterBackend
 from rest_framework import generics
 
 from location import models, serializers
@@ -9,6 +8,7 @@ from utils.views import CreateDestroyGalleryViewMixin
 from rest_framework.permissions import IsAuthenticatedOrReadOnly
 from django.shortcuts import get_object_or_404
 from utils.serializers import ImageBaseSerializer
+from location.filters import RegionFilter
 
 from location import filters
 
@@ -109,11 +109,8 @@ class RegionListCreateView(common.RegionViewMixin, generics.ListCreateAPIView):
     pagination_class = None
     serializer_class = serializers.RegionSerializer
     permission_classes = [IsAuthenticatedOrReadOnly | IsCountryAdmin]
-    filter_backends = (DjangoFilterBackend,)
     ordering_fields = '__all__'
-    filterset_fields = (
-        'country',
-    )
+    filter_class = RegionFilter
 
 
 class RegionRUDView(common.RegionViewMixin, generics.RetrieveUpdateDestroyAPIView):