From 8b4a6b0b740270f98eaf7e036aa442891c12d4a9 Mon Sep 17 00:00:00 2001
From: Kuroshini <o.hayatov@id-east.ru>
Date: Fri, 17 Jan 2020 16:13:27 +0300
Subject: [PATCH] fix employees search

---
 apps/establishment/models.py | 38 +++++++++++++++++++++++++++++++-----
 1 file changed, 33 insertions(+), 5 deletions(-)

diff --git a/apps/establishment/models.py b/apps/establishment/models.py
index d7cc9e7e..5f8ec73d 100644
--- a/apps/establishment/models.py
+++ b/apps/establishment/models.py
@@ -11,12 +11,12 @@ from django.contrib.gis.db.models.functions import Distance
 from django.contrib.gis.geos import Point
 from django.contrib.gis.measure import Distance as DistanceMeasure
 from django.contrib.postgres.fields import ArrayField
-from django.contrib.postgres.search import TrigramDistance
+from django.contrib.postgres.search import TrigramDistance, TrigramSimilarity
 from django.contrib.postgres.indexes import GinIndex
 from django.core.exceptions import ValidationError
 from django.core.validators import MinValueValidator, MaxValueValidator
 from django.db import models
-from django.db.models import When, Case, F, ExpressionWrapper, Subquery, Q, Prefetch
+from django.db.models import When, Case, F, ExpressionWrapper, Subquery, Q, Prefetch, Sum
 from django.utils import timezone
 from django.utils.translation import gettext_lazy as _
 from phonenumber_field.modelfields import PhoneNumberField
@@ -990,9 +990,37 @@ class EmployeeQuerySet(models.QuerySet):
     def trigram_search(self, search_value: str):
         """Search with mistakes by name or last name."""
         return self.annotate(
-            name_distance=TrigramDistance('name', search_value.lower()),
-            last_name_distance=TrigramDistance('last_name', search_value.lower()),
-        ).filter(Q(name_distance__lte=0.7) | Q(last_name_distance__lte=0.7)).order_by('name_distance')
+            search_exact_match=models.Case(
+                models.When(Q(name__iexact=search_value) | Q(last_name__iexact=search_value),
+                            then=100),
+                default=0,
+                output_field=models.FloatField()
+            ),
+            search_contains_match=models.Case(
+                models.When(Q(name__icontains=search_value) | Q(last_name__icontains=search_value),
+                            then=50),
+                default=0,
+                output_field=models.FloatField()
+            ),
+            search_name_similarity=models.Case(
+                models.When(
+                    Q(name__isnull=False),
+                    then=TrigramSimilarity('name', search_value.lower())
+                ),
+                default=0,
+                output_field=models.FloatField()
+            ),
+            search_last_name_similarity=models.Case(
+                models.When(
+                    Q(last_name__isnull=False),
+                    then=TrigramSimilarity('last_name', search_value.lower())
+                ),
+                default=0,
+                output_field=models.FloatField()
+            ),
+            relevance=(F('search_name_similarity') + F('search_exact_match')
+                       + F('search_contains_match') + F('search_last_name_similarity'))
+        ).filter(relevance__gte=0.3).order_by('-relevance')
 
     def search_by_name_or_last_name(self, value):
         """Search by name or last_name."""