from django.db import connection
from django.db.models import CharField
from django.db.models.functions import SHA256
from django.test import TestCase
from django.test.utils import register_lookup

from ..models import Author


class SHA256Tests(TestCase):
    @classmethod
    def setUpTestData(cls):
        Author.objects.bulk_create([
            Author(alias='John Smith'),
            Author(alias='Jordan Élena'),
            Author(alias='皇帝'),
            Author(alias=''),
            Author(alias=None),
        ])

    def test_basic(self):
        authors = Author.objects.annotate(
            sha256_alias=SHA256('alias'),
        ).values_list('sha256_alias', flat=True).order_by('pk')
        self.assertSequenceEqual(
            authors,
            [
                'ef61a579c907bbed674c0dbcbcf7f7af8f851538eef7b8e58c5bee0b8cfdac4a',
                '6e4cce20cd83fc7c202f21a8b2452a68509cf24d1c272a045b5e0cfc43f0d94e',
                '3ad2039e3ec0c88973ae1c0fce5a3dbafdd5a1627da0a92312c54ebfcf43988e',
                'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855',
                'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855'
                if connection.features.interprets_empty_strings_as_nulls else None,
            ],
        )

    def test_transform(self):
        with register_lookup(CharField, SHA256):
            authors = Author.objects.filter(
                alias__sha256='ef61a579c907bbed674c0dbcbcf7f7af8f851538eef7b8e58c5bee0b8cfdac4a',
            ).values_list('alias', flat=True)
            self.assertSequenceEqual(authors, ['John Smith'])