from __future__ import absolute_import

from collections import Callable
from datetime import datetime, timedelta
from mock import patch

from kombu import Queue

from celery import Task

from celery.exceptions import Retry
from celery.five import items, range, string_t
from celery.result import EagerResult
from celery.utils import uuid
from celery.utils.timeutils import parse_iso8601

from celery.tests.case import AppCase, depends_on_current_app


def return_True(*args, **kwargs):
    # Task run functions can't be closures/lambdas, as they're pickled.
    return True


def raise_exception(self, **kwargs):
    raise Exception('%s error' % self.__class__)


class MockApplyTask(Task):
    abstract = True
    applied = 0

    def run(self, x, y):
        return x * y

    def apply_async(self, *args, **kwargs):
        self.applied += 1


class TasksCase(AppCase):

    def setup(self):
        self.mytask = self.app.task(shared=False)(return_True)

        @self.app.task(bind=True, count=0, shared=False)
        def increment_counter(self, increment_by=1):
            self.count += increment_by or 1
            return self.count
        self.increment_counter = increment_counter

        @self.app.task(shared=False)
        def raising():
            raise KeyError('foo')
        self.raising = raising

        @self.app.task(bind=True, max_retries=3, iterations=0, shared=False)
        def retry_task(self, arg1, arg2, kwarg=1, max_retries=None, care=True):
            self.iterations += 1
            rmax = self.max_retries if max_retries is None else max_retries

            assert repr(self.request)
            retries = self.request.retries
            if care and retries >= rmax:
                return arg1
            else:
                raise self.retry(countdown=0, max_retries=rmax)
        self.retry_task = retry_task

        @self.app.task(bind=True, max_retries=3, iterations=0, shared=False)
        def retry_task_noargs(self, **kwargs):
            self.iterations += 1

            if self.request.retries >= 3:
                return 42
            else:
                raise self.retry(countdown=0)
        self.retry_task_noargs = retry_task_noargs

        @self.app.task(bind=True, max_retries=3, iterations=0,
                       base=MockApplyTask, shared=False)
        def retry_task_mockapply(self, arg1, arg2, kwarg=1):
            self.iterations += 1

            retries = self.request.retries
            if retries >= 3:
                return arg1
            raise self.retry(countdown=0)
        self.retry_task_mockapply = retry_task_mockapply

        @self.app.task(bind=True, max_retries=3, iterations=0, shared=False)
        def retry_task_customexc(self, arg1, arg2, kwarg=1, **kwargs):
            self.iterations += 1

            retries = self.request.retries
            if retries >= 3:
                return arg1 + kwarg
            else:
                try:
                    raise MyCustomException('Elaine Marie Benes')
                except MyCustomException as exc:
                    kwargs.update(kwarg=kwarg)
                    raise self.retry(countdown=0, exc=exc)
        self.retry_task_customexc = retry_task_customexc


class MyCustomException(Exception):
    """Random custom exception."""


class test_task_retries(TasksCase):

    def test_retry(self):
        self.retry_task.max_retries = 3
        self.retry_task.iterations = 0
        self.retry_task.apply([0xFF, 0xFFFF])
        self.assertEqual(self.retry_task.iterations, 4)

        self.retry_task.max_retries = 3
        self.retry_task.iterations = 0
        self.retry_task.apply([0xFF, 0xFFFF], {'max_retries': 10})
        self.assertEqual(self.retry_task.iterations, 11)

    def test_retry_no_args(self):
        self.retry_task_noargs.max_retries = 3
        self.retry_task_noargs.iterations = 0
        self.retry_task_noargs.apply(propagate=True).get()
        self.assertEqual(self.retry_task_noargs.iterations, 4)

    def test_retry_kwargs_can_be_empty(self):
        self.retry_task_mockapply.push_request()
        try:
            with self.assertRaises(Retry):
                self.retry_task_mockapply.retry(args=[4, 4], kwargs=None)
        finally:
            self.retry_task_mockapply.pop_request()

    def test_retry_not_eager(self):
        self.retry_task_mockapply.push_request()
        try:
            self.retry_task_mockapply.request.called_directly = False
            exc = Exception('baz')
            try:
                self.retry_task_mockapply.retry(
                    args=[4, 4], kwargs={'task_retries': 0},
                    exc=exc, throw=False,
                )
                self.assertTrue(self.retry_task_mockapply.applied)
            finally:
                self.retry_task_mockapply.applied = 0

            try:
                with self.assertRaises(Retry):
                    self.retry_task_mockapply.retry(
                        args=[4, 4], kwargs={'task_retries': 0},
                        exc=exc, throw=True)
                self.assertTrue(self.retry_task_mockapply.applied)
            finally:
                self.retry_task_mockapply.applied = 0
        finally:
            self.retry_task_mockapply.pop_request()

    def test_retry_with_kwargs(self):
        self.retry_task_customexc.max_retries = 3
        self.retry_task_customexc.iterations = 0
        self.retry_task_customexc.apply([0xFF, 0xFFFF], {'kwarg': 0xF})
        self.assertEqual(self.retry_task_customexc.iterations, 4)

    def test_retry_with_custom_exception(self):
        self.retry_task_customexc.max_retries = 2
        self.retry_task_customexc.iterations = 0
        result = self.retry_task_customexc.apply(
            [0xFF, 0xFFFF], {'kwarg': 0xF},
        )
        with self.assertRaises(MyCustomException):
            result.get()
        self.assertEqual(self.retry_task_customexc.iterations, 3)

    def test_max_retries_exceeded(self):
        self.retry_task.max_retries = 2
        self.retry_task.iterations = 0
        result = self.retry_task.apply([0xFF, 0xFFFF], {'care': False})
        with self.assertRaises(self.retry_task.MaxRetriesExceededError):
            result.get()
        self.assertEqual(self.retry_task.iterations, 3)

        self.retry_task.max_retries = 1
        self.retry_task.iterations = 0
        result = self.retry_task.apply([0xFF, 0xFFFF], {'care': False})
        with self.assertRaises(self.retry_task.MaxRetriesExceededError):
            result.get()
        self.assertEqual(self.retry_task.iterations, 2)


class test_canvas_utils(TasksCase):

    def test_si(self):
        self.assertTrue(self.retry_task.si())
        self.assertTrue(self.retry_task.si().immutable)

    def test_chunks(self):
        self.assertTrue(self.retry_task.chunks(range(100), 10))

    def test_map(self):
        self.assertTrue(self.retry_task.map(range(100)))

    def test_starmap(self):
        self.assertTrue(self.retry_task.starmap(range(100)))

    def test_on_success(self):
        self.retry_task.on_success(1, 1, (), {})


class test_tasks(TasksCase):

    def now(self):
        return self.app.now()

    @depends_on_current_app
    def test_unpickle_task(self):
        import pickle

        @self.app.task(shared=True)
        def xxx():
            pass
        self.assertIs(pickle.loads(pickle.dumps(xxx)), xxx.app.tasks[xxx.name])

    def test_AsyncResult(self):
        task_id = uuid()
        result = self.retry_task.AsyncResult(task_id)
        self.assertEqual(result.backend, self.retry_task.backend)
        self.assertEqual(result.id, task_id)

    def assertNextTaskDataEqual(self, consumer, presult, task_name,
                                test_eta=False, test_expires=False, **kwargs):
        next_task = consumer.queues[0].get(accept=['pickle'])
        task_data = next_task.decode()
        self.assertEqual(task_data['id'], presult.id)
        self.assertEqual(task_data['task'], task_name)
        task_kwargs = task_data.get('kwargs', {})
        if test_eta:
            self.assertIsInstance(task_data.get('eta'), string_t)
            to_datetime = parse_iso8601(task_data.get('eta'))
            self.assertIsInstance(to_datetime, datetime)
        if test_expires:
            self.assertIsInstance(task_data.get('expires'), string_t)
            to_datetime = parse_iso8601(task_data.get('expires'))
            self.assertIsInstance(to_datetime, datetime)
        for arg_name, arg_value in items(kwargs):
            self.assertEqual(task_kwargs.get(arg_name), arg_value)

    def test_incomplete_task_cls(self):

        class IncompleteTask(Task):
            app = self.app
            name = 'c.unittest.t.itask'

        with self.assertRaises(NotImplementedError):
            IncompleteTask().run()

    def test_task_kwargs_must_be_dictionary(self):
        with self.assertRaises(ValueError):
            self.increment_counter.apply_async([], 'str')

    def test_task_args_must_be_list(self):
        with self.assertRaises(ValueError):
            self.increment_counter.apply_async('str', {})

    def test_regular_task(self):
        self.assertIsInstance(self.mytask, Task)
        self.assertTrue(self.mytask.run())
        self.assertTrue(isinstance(self.mytask, Callable),
                        'Task class is callable()')
        self.assertTrue(self.mytask(), 'Task class runs run() when called')

        with self.app.connection_or_acquire() as conn:
            consumer = self.app.amqp.TaskConsumer(conn)
            with self.assertRaises(NotImplementedError):
                consumer.receive('foo', 'foo')
            consumer.purge()
            self.assertIsNone(consumer.queues[0].get())
            self.app.amqp.TaskConsumer(conn, queues=[Queue('foo')])

            # Without arguments.
            presult = self.mytask.delay()
            self.assertNextTaskDataEqual(consumer, presult, self.mytask.name)

            # With arguments.
            presult2 = self.mytask.apply_async(
                kwargs=dict(name='George Costanza'),
            )
            self.assertNextTaskDataEqual(
                consumer, presult2, self.mytask.name, name='George Costanza',
            )

            # send_task
            sresult = self.app.send_task(self.mytask.name,
                                         kwargs=dict(name='Elaine M. Benes'))
            self.assertNextTaskDataEqual(
                consumer, sresult, self.mytask.name, name='Elaine M. Benes',
            )

            # With eta.
            presult2 = self.mytask.apply_async(
                kwargs=dict(name='George Costanza'),
                eta=self.now() + timedelta(days=1),
                expires=self.now() + timedelta(days=2),
            )
            self.assertNextTaskDataEqual(
                consumer, presult2, self.mytask.name,
                name='George Costanza', test_eta=True, test_expires=True,
            )

            # With countdown.
            presult2 = self.mytask.apply_async(
                kwargs=dict(name='George Costanza'), countdown=10, expires=12,
            )
            self.assertNextTaskDataEqual(
                consumer, presult2, self.mytask.name,
                name='George Costanza', test_eta=True, test_expires=True,
            )

            # Discarding all tasks.
            consumer.purge()
            self.mytask.apply_async()
            self.assertEqual(consumer.purge(), 1)
            self.assertIsNone(consumer.queues[0].get())

            self.assertFalse(presult.successful())
            self.mytask.backend.mark_as_done(presult.id, result=None)
            self.assertTrue(presult.successful())

    def test_repr_v2_compat(self):
        self.mytask.__v2_compat__ = True
        self.assertIn('v2 compatible', repr(self.mytask))

    def test_apply_with_self(self):

        @self.app.task(__self__=42, shared=False)
        def tawself(self):
            return self

        self.assertEqual(tawself.apply().get(), 42)

        self.assertEqual(tawself(), 42)

    def test_context_get(self):
        self.mytask.push_request()
        try:
            request = self.mytask.request
            request.foo = 32
            self.assertEqual(request.get('foo'), 32)
            self.assertEqual(request.get('bar', 36), 36)
            request.clear()
        finally:
            self.mytask.pop_request()

    def test_task_class_repr(self):
        self.assertIn('class Task of', repr(self.mytask.app.Task))
        self.mytask.app.Task._app = None
        self.assertIn('unbound', repr(self.mytask.app.Task, ))

    def test_bind_no_magic_kwargs(self):
        self.mytask.accept_magic_kwargs = None
        self.mytask.bind(self.mytask.app)

    def test_annotate(self):
        with patch('celery.app.task.resolve_all_annotations') as anno:
            anno.return_value = [{'FOO': 'BAR'}]

            @self.app.task(shared=False)
            def task():
                pass
            task.annotate()
            self.assertEqual(task.FOO, 'BAR')

    def test_after_return(self):
        self.mytask.push_request()
        try:
            self.mytask.request.chord = self.mytask.s()
            self.mytask.after_return('SUCCESS', 1.0, 'foobar', (), {}, None)
            self.mytask.request.clear()
        finally:
            self.mytask.pop_request()

    def test_send_task_sent_event(self):
        with self.app.connection() as conn:
            self.app.conf.CELERY_SEND_TASK_SENT_EVENT = True
            self.assertTrue(self.app.amqp.TaskProducer(conn).send_sent_event)

    def test_update_state(self):

        @self.app.task(shared=False)
        def yyy():
            pass

        yyy.push_request()
        try:
            tid = uuid()
            yyy.update_state(tid, 'FROBULATING', {'fooz': 'baaz'})
            self.assertEqual(yyy.AsyncResult(tid).status, 'FROBULATING')
            self.assertDictEqual(yyy.AsyncResult(tid).result, {'fooz': 'baaz'})

            yyy.request.id = tid
            yyy.update_state(state='FROBUZATING', meta={'fooz': 'baaz'})
            self.assertEqual(yyy.AsyncResult(tid).status, 'FROBUZATING')
            self.assertDictEqual(yyy.AsyncResult(tid).result, {'fooz': 'baaz'})
        finally:
            yyy.pop_request()

    def test_repr(self):

        @self.app.task(shared=False)
        def task_test_repr():
            pass

        self.assertIn('task_test_repr', repr(task_test_repr))

    def test_has___name__(self):

        @self.app.task(shared=False)
        def yyy2():
            pass

        self.assertTrue(yyy2.__name__)


class test_apply_task(TasksCase):

    def test_apply_throw(self):
        with self.assertRaises(KeyError):
            self.raising.apply(throw=True)

    def test_apply_with_CELERY_EAGER_PROPAGATES_EXCEPTIONS(self):
        self.app.conf.CELERY_EAGER_PROPAGATES_EXCEPTIONS = True
        with self.assertRaises(KeyError):
            self.raising.apply()

    def test_apply(self):
        self.increment_counter.count = 0

        e = self.increment_counter.apply()
        self.assertIsInstance(e, EagerResult)
        self.assertEqual(e.get(), 1)

        e = self.increment_counter.apply(args=[1])
        self.assertEqual(e.get(), 2)

        e = self.increment_counter.apply(kwargs={'increment_by': 4})
        self.assertEqual(e.get(), 6)

        self.assertTrue(e.successful())
        self.assertTrue(e.ready())
        self.assertTrue(repr(e).startswith('<EagerResult:'))

        f = self.raising.apply()
        self.assertTrue(f.ready())
        self.assertFalse(f.successful())
        self.assertTrue(f.traceback)
        with self.assertRaises(KeyError):
            f.get()