from django.db.models import CharField

from django.db.models import Value as V

from django.db.models.functions import Coalesce, Length, Upper

from django.test import TestCase

from django.test.utils import register_lookup

from .models import Author

class UpperBilateral(Upper):

    bilateral = True

class FunctionTests(TestCase):

    def test_nested_function_ordering(self):

        Author.objects.create(name="John Smith")

        Author.objects.create(name="Rhonda Simpson", alias="ronny")

        authors = Author.objects.order_by(Length(Coalesce("alias", "name")))

        self.assertQuerysetEqual(

            authors,

            [

                "Rhonda Simpson",

                "John Smith",

            ],

            lambda a: a.name,

        )

        authors = Author.objects.order_by(Length(Coalesce("alias", "name")).desc())

        self.assertQuerysetEqual(

            authors,

            [

                "John Smith",

                "Rhonda Simpson",

            ],

            lambda a: a.name,

        )

    def test_func_transform_bilateral(self):

        with register_lookup(CharField, UpperBilateral):

            Author.objects.create(name="John Smith", alias="smithj")

            Author.objects.create(name="Rhonda")

            authors = Author.objects.filter(name__upper__exact="john smith")

            self.assertQuerysetEqual(

                authors.order_by("name"),

                [

                    "John Smith",

                ],

                lambda a: a.name,

            )

    def test_func_transform_bilateral_multivalue(self):

        with register_lookup(CharField, UpperBilateral):

            Author.objects.create(name="John Smith", alias="smithj")

            Author.objects.create(name="Rhonda")

            authors = Author.objects.filter(name__upper__in=["john smith", "rhonda"])

            self.assertQuerysetEqual(

                authors.order_by("name"),

                [

                    "John Smith",

                    "Rhonda",

                ],

                lambda a: a.name,

            )

    def test_function_as_filter(self):

        Author.objects.create(name="John Smith", alias="SMITHJ")

        Author.objects.create(name="Rhonda")

        self.assertQuerysetEqual(

            Author.objects.filter(alias=Upper(V("smithj"))),

            ["John Smith"],

            lambda x: x.name,

        )

        self.assertQuerysetEqual(

            Author.objects.exclude(alias=Upper(V("smithj"))),

            ["Rhonda"],

            lambda x: x.name,

        )