from django.test import TestCase
from .views import determine_search_strategy


class DetermineSearchStrategyTestCase(TestCase):
    """
    Тесты для функции determine_search_strategy().

    Проверяют, что функция правильно определяет стратегию поиска
    на основе содержимого query.
    """

    # ===== email_prefix: query заканчивается на @ =====
    def test_email_prefix_simple(self):
        """Query "team_x3m@" должен вернуть ('email_prefix', 'team_x3m')"""
        strategy, search_value = determine_search_strategy('team_x3m@')
        self.assertEqual(strategy, 'email_prefix')
        self.assertEqual(search_value, 'team_x3m')

    def test_email_prefix_with_domain_symbol(self):
        """Query "user_name@" должен вернуть ('email_prefix', 'user_name')"""
        strategy, search_value = determine_search_strategy('user_name@')
        self.assertEqual(strategy, 'email_prefix')
        self.assertEqual(search_value, 'user_name')

    def test_email_prefix_with_numbers(self):
        """Query "test123@" должен вернуть ('email_prefix', 'test123')"""
        strategy, search_value = determine_search_strategy('test123@')
        self.assertEqual(strategy, 'email_prefix')
        self.assertEqual(search_value, 'test123')

    # ===== email_domain: query начинается с @ =====
    def test_email_domain_simple(self):
        """Query "@bk" должен вернуть ('email_domain', 'bk')"""
        strategy, search_value = determine_search_strategy('@bk')
        self.assertEqual(strategy, 'email_domain')
        self.assertEqual(search_value, 'bk')

    def test_email_domain_with_extension(self):
        """Query "@bk.ru" должен вернуть ('email_domain', 'bk.ru')"""
        strategy, search_value = determine_search_strategy('@bk.ru')
        self.assertEqual(strategy, 'email_domain')
        self.assertEqual(search_value, 'bk.ru')

    def test_email_domain_with_multiple_dots(self):
        """Query "@mail.google.com" должен вернуть ('email_domain', 'mail.google.com')"""
        strategy, search_value = determine_search_strategy('@mail.google.com')
        self.assertEqual(strategy, 'email_domain')
        self.assertEqual(search_value, 'mail.google.com')

    # ===== email_full: query содержит и локальную часть, и домен =====
    def test_email_full_simple(self):
        """Query "test@bk.ru" должен вернуть ('email_full', 'test@bk.ru')"""
        strategy, search_value = determine_search_strategy('test@bk.ru')
        self.assertEqual(strategy, 'email_full')
        self.assertEqual(search_value, 'test@bk.ru')

    def test_email_full_partial(self):
        """Query "test@bk" должен вернуть ('email_full', 'test@bk')"""
        strategy, search_value = determine_search_strategy('test@bk')
        self.assertEqual(strategy, 'email_full')
        self.assertEqual(search_value, 'test@bk')

    def test_email_full_complex(self):
        """Query "user.name@mail.example.com" должен вернуть ('email_full', ...)"""
        strategy, search_value = determine_search_strategy('user.name@mail.example.com')
        self.assertEqual(strategy, 'email_full')
        self.assertEqual(search_value, 'user.name@mail.example.com')

    # ===== universal: query без @, 3+ символов =====
    def test_universal_three_chars(self):
        """Query "natul" (5 символов) должен вернуть ('universal', 'natul')"""
        strategy, search_value = determine_search_strategy('natul')
        self.assertEqual(strategy, 'universal')
        self.assertEqual(search_value, 'natul')

    def test_universal_three_chars_exact(self):
        """Query "abc" (3 символа) должен вернуть ('universal', 'abc')"""
        strategy, search_value = determine_search_strategy('abc')
        self.assertEqual(strategy, 'universal')
        self.assertEqual(search_value, 'abc')

    def test_universal_cyrillic(self):
        """Query "наталь" (6 символов) должен вернуть ('universal', 'наталь')"""
        strategy, search_value = determine_search_strategy('наталь')
        self.assertEqual(strategy, 'universal')
        self.assertEqual(search_value, 'наталь')

    def test_universal_mixed(self):
        """Query "Test123" (7 символов) должен вернуть ('universal', 'Test123')"""
        strategy, search_value = determine_search_strategy('Test123')
        self.assertEqual(strategy, 'universal')
        self.assertEqual(search_value, 'Test123')

    # ===== name_only: очень короткие запросы (< 3 символов без @) =====
    def test_name_only_single_char(self):
        """Query "t" должен вернуть ('name_only', 't')"""
        strategy, search_value = determine_search_strategy('t')
        self.assertEqual(strategy, 'name_only')
        self.assertEqual(search_value, 't')

    def test_name_only_two_chars(self):
        """Query "te" должен вернуть ('name_only', 'te')"""
        strategy, search_value = determine_search_strategy('te')
        self.assertEqual(strategy, 'name_only')
        self.assertEqual(search_value, 'te')

    def test_name_only_two_chars_cyrillic(self):
        """Query "на" (2 символа) должен вернуть ('name_only', 'на')"""
        strategy, search_value = determine_search_strategy('на')
        self.assertEqual(strategy, 'name_only')
        self.assertEqual(search_value, 'на')

    # ===== edge cases =====
    def test_empty_string(self):
        """Query "" должен вернуть ('name_only', '')"""
        strategy, search_value = determine_search_strategy('')
        self.assertEqual(strategy, 'name_only')
        self.assertEqual(search_value, '')

    def test_only_at_symbol(self):
        """Query "@" должен вернуть ('email_domain', '')"""
        strategy, search_value = determine_search_strategy('@')
        self.assertEqual(strategy, 'email_domain')
        self.assertEqual(search_value, '')

    def test_multiple_at_symbols(self):
        """Query "test@example@com" должен обработать первый @"""
        strategy, search_value = determine_search_strategy('test@example@com')
        self.assertEqual(strategy, 'email_full')
        self.assertEqual(search_value, 'test@example@com')

    def test_spaces_in_query(self):
        """Query "Ivan Petrov" должен вернуть ('universal', 'Ivan Petrov')"""
        strategy, search_value = determine_search_strategy('Ivan Petrov')
        self.assertEqual(strategy, 'universal')
        self.assertEqual(search_value, 'Ivan Petrov')

    # ===== real-world examples =====
    def test_real_world_problematic_case(self):
        """
        Real-world case: query "team_x3m@" не должен найти "natulj@bk.ru"
        Используется email_prefix со istartswith вместо icontains
        """
        strategy, search_value = determine_search_strategy('team_x3m@')
        self.assertEqual(strategy, 'email_prefix')
        # Важно: стратегия email_prefix, не universal или email_full
        self.assertNotEqual(strategy, 'universal')

    def test_real_world_domain_search(self):
        """Real-world case: query "@bk" должен найти все @bk.ru"""
        strategy, search_value = determine_search_strategy('@bk')
        self.assertEqual(strategy, 'email_domain')
        self.assertEqual(search_value, 'bk')

    def test_real_world_name_search(self):
        """Real-world case: query "natul" должен найти "Наталья" и "natulj@bk.ru" """
        strategy, search_value = determine_search_strategy('natul')
        self.assertEqual(strategy, 'universal')
        self.assertEqual(search_value, 'natul')