"""Tests for core signal dispatcher utilities."""

from __future__ import annotations

from django.contrib.auth import get_user_model
from django.db.models.signals import post_save
from django.test import TestCase

from apps.core.signals import (
    SignalDispatcher,
    on_post_delete,
    on_post_save,
    on_pre_delete,
    on_pre_save,
    signal_dispatcher,
)
from tests.utils.fixtures import fake


class SignalDispatcherTest(TestCase):
    def test_register_connect_disconnect(self):
        dispatcher = SignalDispatcher()
        events: list[int] = []

        def handler(sender, instance, **_kwargs):
            events.append(instance.pk)

        dispatcher.register(
            signal=post_save,
            sender="user.User",
            handler=handler,
            description="track user create",
        )
        dispatcher.connect_all()

        user = get_user_model().objects.create_user(
            email=fake.email(), username=fake.user_name(), password="pass"
        )

        self.assertIn(user.pk, events)
        self.assertTrue(dispatcher.list_handlers())

        dispatcher.disconnect_all()
        self.assertFalse(dispatcher._connected)

    def test_connect_all_idempotent(self):
        dispatcher = SignalDispatcher()
        dispatcher.register(
            signal=post_save,
            sender="user.User",
            handler=lambda *_args, **_kwargs: None,
        )
        dispatcher.connect_all()
        dispatcher.connect_all()
        self.assertTrue(dispatcher._connected)

    def test_decorator_registers_handler(self):
        original_handlers = list(signal_dispatcher._handlers)
        original_connected = signal_dispatcher._connected
        events: list[int] = []

        try:
            signal_dispatcher._handlers = []
            signal_dispatcher._connected = False

            @on_post_save("user.User", description="decorator")
            def _handler(sender, instance, **_kwargs):
                events.append(instance.pk)

            @on_pre_save("user.User")
            def _pre_save(sender, instance, **_kwargs):
                return None

            @on_post_delete("user.User")
            def _post_delete(sender, instance, **_kwargs):
                return None

            @on_pre_delete("user.User")
            def _pre_delete(sender, instance, **_kwargs):
                return None

            signal_dispatcher.connect_all()
            user = get_user_model().objects.create_user(
                email=fake.email(), username=fake.user_name(), password="pass"
            )
            self.assertIn(user.pk, events)
            self.assertTrue(signal_dispatcher.list_handlers())
        finally:
            signal_dispatcher.disconnect_all()
            signal_dispatcher._handlers = original_handlers
            signal_dispatcher._connected = original_connected