"""Tests for core Celery tasks"""

import logging
from io import StringIO

from apps.core.tasks import (
    BaseTask,
    IdempotentTask,
    PeriodicTask,
    TimedTask,
    TransactionalTask,
)
from celery import Task
from core.celery import app as celery_app
from django.test import TestCase


@celery_app.task(base=BaseTask, bind=True)
def base_task(self, marker: str):
    return marker


@celery_app.task(base=TransactionalTask, bind=True)
def transactional_task(self, marker: str):
    from apps.core.models import BackgroundJob

    BackgroundJob.objects.create(task_id=marker, task_name="test.tx")
    if marker == "fail":
        raise ValueError("boom")
    return marker


@celery_app.task(base=IdempotentTask, bind=True)
def idempotent_task(self, marker: str):
    from apps.core.models import BackgroundJob

    BackgroundJob.objects.create(task_id=marker, task_name="test.idem")
    return marker


@celery_app.task(base=TimedTask, bind=True)
def timed_task(self, marker: str):
    return marker


class BaseTaskTest(TestCase):
    """Tests for BaseTask"""

    def test_inherits_from_celery_task(self):
        """Test BaseTask inherits from Celery Task"""
        self.assertTrue(issubclass(BaseTask, Task))

    def test_has_default_retry_settings(self):
        """Test BaseTask has default retry settings"""
        self.assertEqual(BaseTask.max_retries, 3)
        self.assertTrue(BaseTask.retry_backoff)
        self.assertEqual(BaseTask.retry_backoff_max, 600)

    def test_acks_late_enabled(self):
        """Test acks_late is enabled"""
        self.assertTrue(BaseTask.acks_late)

    def test_reject_on_worker_lost(self):
        """Test reject_on_worker_lost is enabled"""
        self.assertTrue(BaseTask.reject_on_worker_lost)


class TransactionalTaskTest(TestCase):
    """Tests for TransactionalTask"""

    def test_inherits_from_base_task(self):
        """Test TransactionalTask inherits from BaseTask"""
        self.assertTrue(issubclass(TransactionalTask, BaseTask))


class IdempotentTaskTest(TestCase):
    """Tests for IdempotentTask"""

    def test_inherits_from_base_task(self):
        """Test IdempotentTask inherits from BaseTask"""
        self.assertTrue(issubclass(IdempotentTask, BaseTask))

    def test_has_lock_timeout(self):
        """Test IdempotentTask has lock_timeout attribute"""
        self.assertEqual(IdempotentTask.lock_timeout, 3600)


class TimedTaskTest(TestCase):
    """Tests for TimedTask"""

    def test_inherits_from_base_task(self):
        """Test TimedTask inherits from BaseTask"""
        self.assertTrue(issubclass(TimedTask, BaseTask))

    def test_has_slow_threshold(self):
        """Test TimedTask has slow_threshold attribute"""
        self.assertEqual(TimedTask.slow_threshold, 60)


class PeriodicTaskTest(TestCase):
    """Tests for PeriodicTask"""

    def test_inherits_from_timed_task(self):
        """Test PeriodicTask inherits from TimedTask"""
        self.assertTrue(issubclass(PeriodicTask, TimedTask))

    def test_max_retries_is_one(self):
        """Test max_retries is 1 for periodic tasks"""
        self.assertEqual(PeriodicTask.max_retries, 1)

    def test_autoretry_for_is_empty(self):
        """Test autoretry_for is empty for periodic tasks"""
        self.assertEqual(PeriodicTask.autoretry_for, ())


class TaskRuntimeBehaviorTest(TestCase):
    def setUp(self):
        self.logger = logging.getLogger("apps.core.tasks")
        self.logger.setLevel(logging.INFO)
        self.stream = StringIO()
        handler = logging.StreamHandler(self.stream)
        self.logger.handlers = []
        self.logger.addHandler(handler)

    def test_base_task_hooks(self):
        base_task.apply(args=("ok",)).get()
        base_task.request_stack.push(type("Req", (), {"retries": 1})())
        base_task.on_retry(Exception("retry"), "id-1", (), {}, None)
        base_task.request_stack.pop()
        output = self.stream.getvalue()
        self.assertIn("base_task", output)

    def test_transactional_task_rolls_back(self):
        from apps.core.models import BackgroundJob

        with self.assertRaises(ValueError):
            transactional_task.apply(args=("fail",)).get()

        self.assertFalse(BackgroundJob.objects.filter(task_id="fail").exists())

    def test_transactional_task_commits(self):
        from apps.core.models import BackgroundJob

        transactional_task.apply(args=("ok",)).get()
        self.assertTrue(BackgroundJob.objects.filter(task_id="ok").exists())

    def test_idempotent_task_skips_second_call(self):
        from apps.core.models import BackgroundJob

        idempotent_task.apply(args=("idem",)).get()
        idempotent_task.apply(args=("idem",)).get()
        self.assertEqual(BackgroundJob.objects.filter(task_id="idem").count(), 1)

    def test_timed_task_logs_warning(self):
        timed_task.slow_threshold = 0
        result = timed_task.apply(args=("payload",)).get()
        self.assertEqual(result, "payload")
        output = self.stream.getvalue()
        self.assertIn("timed_task", output)