from __future__ import absolute_import

from datetime import datetime, timedelta
from itertools import count

from celery.five import monotonic
from celery.schedules import schedule, crontab
from celery.utils.timeutils import timedelta_seconds

from djcelery import schedulers
from djcelery import celery
from djcelery.app import app
from djcelery.models import PeriodicTask, IntervalSchedule, CrontabSchedule
from djcelery.models import PeriodicTasks
from djcelery.tests.utils import unittest
from djcelery.compat import unicode


def create_model_interval(schedule, **kwargs):
    return create_model(interval=IntervalSchedule.from_schedule(schedule),
                        **kwargs)


def create_model_crontab(schedule, **kwargs):
    return create_model(crontab=CrontabSchedule.from_schedule(schedule),
                        **kwargs)


_next_id_get = count(0)
_next_id = lambda: next(_next_id_get)


def create_model(Model=PeriodicTask, **kwargs):
    entry = dict(name='thefoo{0}'.format(_next_id()),
                 task='djcelery.unittest.add{0}'.format(_next_id()),
                 args='[2, 2]',
                 kwargs='{"callback": "foo"}',
                 queue='xaz',
                 routing_key='cpu',
                 exchange='foo')
    return Model(**dict(entry, **kwargs))


class EntryTrackSave(schedulers.ModelEntry):

    def __init__(self, *args, **kwargs):
        self.saved = 0
        super(EntryTrackSave, self).__init__(*args, **kwargs)

    def save(self):
        self.saved += 1
        super(EntryTrackSave, self).save()


class EntrySaveRaises(schedulers.ModelEntry):

    def save(self):
        raise RuntimeError('this is expected')


class TrackingScheduler(schedulers.DatabaseScheduler):
    Entry = EntryTrackSave

    def __init__(self, *args, **kwargs):
        self.flushed = 0
        schedulers.DatabaseScheduler.__init__(self, *args, **kwargs)

    def sync(self):
        self.flushed += 1
        schedulers.DatabaseScheduler.sync(self)


class test_ModelEntry(unittest.TestCase):
    Entry = EntryTrackSave

    def tearDown(self):
        PeriodicTask.objects.all().delete()

    def test_entry(self):
        m = create_model_interval(schedule(timedelta(seconds=10)))
        e = self.Entry(m)

        self.assertListEqual(e.args, [2, 2])
        self.assertDictEqual(e.kwargs, {'callback': 'foo'})
        self.assertTrue(e.schedule)
        self.assertEqual(e.total_run_count, 0)
        self.assertIsInstance(e.last_run_at, datetime)
        self.assertDictContainsSubset({'queue': 'xaz',
                                       'exchange': 'foo',
                                       'routing_key': 'cpu'}, e.options)

        right_now = celery.now()
        m2 = create_model_interval(schedule(timedelta(seconds=10)),
                                   last_run_at=right_now)
        self.assertTrue(m2.last_run_at)
        e2 = self.Entry(m2)
        self.assertIs(e2.last_run_at, right_now)

        e3 = e2.next()
        self.assertGreater(e3.last_run_at, e2.last_run_at)
        self.assertEqual(e3.total_run_count, 1)


class test_DatabaseScheduler(unittest.TestCase):
    Scheduler = TrackingScheduler

    def setUp(self):
        PeriodicTask.objects.all().delete()
        self.prev_schedule = celery.conf.CELERYBEAT_SCHEDULE
        celery.conf.CELERYBEAT_SCHEDULE = {}
        m1 = create_model_interval(schedule(timedelta(seconds=10)))
        m2 = create_model_interval(schedule(timedelta(minutes=20)))
        m3 = create_model_crontab(crontab(minute='2,4,5'))
        for obj in m1, m2, m3:
            obj.save()
        self.s = self.Scheduler(app=app)
        self.m1 = PeriodicTask.objects.get(name=m1.name)
        self.m2 = PeriodicTask.objects.get(name=m2.name)
        self.m3 = PeriodicTask.objects.get(name=m3.name)

    def tearDown(self):
        celery.conf.CELERYBEAT_SCHEDULE = self.prev_schedule
        PeriodicTask.objects.all().delete()

    def test_constructor(self):
        self.assertIsInstance(self.s._dirty, set)
        self.assertIsNone(self.s._last_sync)
        self.assertTrue(self.s.sync_every)

    def test_all_as_schedule(self):
        sched = self.s.schedule
        self.assertTrue(sched)
        self.assertEqual(len(sched), 4)
        self.assertIn('celery.backend_cleanup', sched)
        for n, e in sched.items():
            self.assertIsInstance(e, self.s.Entry)

    def test_schedule_changed(self):
        self.m2.args = '[16, 16]'
        self.m2.save()
        e2 = self.s.schedule[self.m2.name]
        self.assertListEqual(e2.args, [16, 16])

        self.m1.args = '[32, 32]'
        self.m1.save()
        e1 = self.s.schedule[self.m1.name]
        self.assertListEqual(e1.args, [32, 32])
        e1 = self.s.schedule[self.m1.name]
        self.assertListEqual(e1.args, [32, 32])

        self.m3.delete()
        self.assertRaises(KeyError, self.s.schedule.__getitem__, self.m3.name)

    def test_should_sync(self):
        self.assertTrue(self.s.should_sync())
        self.s._last_sync = monotonic()
        self.assertFalse(self.s.should_sync())
        self.s._last_sync -= self.s.sync_every
        self.assertTrue(self.s.should_sync())

    def test_reserve(self):
        e1 = self.s.schedule[self.m1.name]
        self.s.schedule[self.m1.name] = self.s.reserve(e1)
        self.assertEqual(self.s.flushed, 1)

        e2 = self.s.schedule[self.m2.name]
        self.s.schedule[self.m2.name] = self.s.reserve(e2)
        self.assertEqual(self.s.flushed, 1)
        self.assertIn(self.m2.name, self.s._dirty)

    def test_sync_saves_last_run_at(self):
        e1 = self.s.schedule[self.m2.name]
        last_run = e1.last_run_at
        last_run2 = last_run - timedelta(days=1)
        e1.model.last_run_at = last_run2
        self.s._dirty.add(self.m2.name)
        self.s.sync()

        e2 = self.s.schedule[self.m2.name]
        self.assertEqual(e2.last_run_at, last_run2)

    def test_sync_syncs_before_save(self):
        # Get the entry for m2
        e1 = self.s.schedule[self.m2.name]

        # Increment the entry (but make sure it doesn't sync)
        self.s._last_sync = monotonic()
        e2 = self.s.schedule[e1.name] = self.s.reserve(e1)
        self.assertEqual(self.s.flushed, 1)

        # Fetch the raw object from db, change the args
        # and save the changes.
        m2 = PeriodicTask.objects.get(pk=self.m2.pk)
        m2.args = '[16, 16]'
        m2.save()

        # get_schedule should now see the schedule has changed.
        # and also sync the dirty objects.
        e3 = self.s.schedule[self.m2.name]
        self.assertEqual(self.s.flushed, 2)
        self.assertEqual(e3.last_run_at, e2.last_run_at)
        self.assertListEqual(e3.args, [16, 16])

    def test_sync_not_dirty(self):
        self.s._dirty.clear()
        self.s.sync()

    def test_sync_object_gone(self):
        self.s._dirty.add('does-not-exist')
        self.s.sync()

    def test_sync_rollback_on_save_error(self):
        self.s.schedule[self.m1.name] = EntrySaveRaises(self.m1)
        self.s._dirty.add(self.m1.name)
        self.assertRaises(RuntimeError, self.s.sync)


class test_models(unittest.TestCase):

    def test_IntervalSchedule_unicode(self):
        self.assertEqual(unicode(IntervalSchedule(every=1, period='seconds')),
                         'every second')
        self.assertEqual(unicode(IntervalSchedule(every=10, period='seconds')),
                         'every 10 seconds')

    def test_CrontabSchedule_unicode(self):
        self.assertEqual(unicode(CrontabSchedule(minute=3,
                                                 hour=3,
                                                 day_of_week=None)),
                         '3 3 * * * (m/h/d/dM/MY)')
        self.assertEqual(unicode(CrontabSchedule(minute=3,
                                                 hour=3,
                                                 day_of_week='tue',
                                                 day_of_month='*/2',
                                                 month_of_year='4,6')),
                         '3 3 tue */2 4,6 (m/h/d/dM/MY)')

    def test_PeriodicTask_unicode_interval(self):
        p = create_model_interval(schedule(timedelta(seconds=10)))
        self.assertEqual(unicode(p),
                         '{0}: every 10.0 seconds'.format(p.name))

    def test_PeriodicTask_unicode_crontab(self):
        p = create_model_crontab(crontab(hour='4, 5', day_of_week='4, 5'))
        self.assertEqual(unicode(p),
                         '{0}: * 4,5 4,5 * * (m/h/d/dM/MY)'.format(p.name))

    def test_PeriodicTask_schedule_property(self):
        p1 = create_model_interval(schedule(timedelta(seconds=10)))
        s1 = p1.schedule
        self.assertEqual(timedelta_seconds(s1.run_every), 10)

        p2 = create_model_crontab(crontab(hour='4, 5',
                                          minute='10,20,30',
                                          day_of_month='1-7',
                                          month_of_year='*/3'))
        s2 = p2.schedule
        self.assertSetEqual(s2.hour, set([4, 5]))
        self.assertSetEqual(s2.minute, set([10, 20, 30]))
        self.assertSetEqual(s2.day_of_week, set([0, 1, 2, 3, 4, 5, 6]))
        self.assertSetEqual(s2.day_of_month, set([1, 2, 3, 4, 5, 6, 7]))
        self.assertSetEqual(s2.month_of_year, set([1, 4, 7, 10]))

    def test_PeriodicTask_unicode_no_schedule(self):
        p = create_model()
        self.assertEqual(unicode(p), '{0}: {{no schedule}}'.format(p.name))

    def test_CrontabSchedule_schedule(self):
        s = CrontabSchedule(minute='3, 7', hour='3, 4', day_of_week='*',
                            day_of_month='1, 16', month_of_year='1, 7')
        self.assertEqual(s.schedule.minute, set([3, 7]))
        self.assertEqual(s.schedule.hour, set([3, 4]))
        self.assertEqual(s.schedule.day_of_week, set([0, 1, 2, 3, 4, 5, 6]))
        self.assertEqual(s.schedule.day_of_month, set([1, 16]))
        self.assertEqual(s.schedule.month_of_year, set([1, 7]))


class test_model_PeriodicTasks(unittest.TestCase):

    def setUp(self):
        PeriodicTasks.objects.all().delete()

    def test_track_changes(self):
        self.assertIsNone(PeriodicTasks.last_change())
        m1 = create_model_interval(schedule(timedelta(seconds=10)))
        m1.save()
        x = PeriodicTasks.last_change()
        self.assertTrue(x)
        m1.args = '(23, 24)'
        m1.save()
        y = PeriodicTasks.last_change()
        self.assertTrue(y)
        self.assertGreater(y, x)