import datetime
import re
from unittest.mock import Mock

from redis import Redis

from rq.exceptions import TimeoutFormatError
from rq.utils import (
    as_text,
    backend_class,
    ceildiv,
    ensure_list,
    first,
    get_call_string,
    get_version,
    import_attribute,
    is_nonstring_iterable,
    parse_timeout,
    split_list,
    truncate_long_string,
    utcparse,
)
from rq.worker import SimpleWorker
from tests import RQTestCase, fixtures


class TestUtils(RQTestCase):
    def test_parse_timeout(self):
        """Ensure function parse_timeout works correctly"""
        self.assertEqual(12, parse_timeout(12))
        self.assertEqual(12, parse_timeout('12'))
        self.assertEqual(12, parse_timeout('12s'))
        self.assertEqual(720, parse_timeout('12m'))
        self.assertEqual(3600, parse_timeout('1h'))
        self.assertEqual(3600, parse_timeout('1H'))

    def test_parse_timeout_coverage_scenarios(self):
        """Test parse_timeout edge cases for coverage"""
        timeouts = ['h12', 'h', 'm', 's', '10k']

        self.assertEqual(None, parse_timeout(None))
        with self.assertRaises(TimeoutFormatError):
            for timeout in timeouts:
                parse_timeout(timeout)

    def test_first(self):
        """Ensure function first works correctly"""
        self.assertEqual(42, first([0, False, None, [], (), 42]))
        self.assertEqual(None, first([0, False, None, [], ()]))
        self.assertEqual('ohai', first([0, False, None, [], ()], default='ohai'))
        self.assertEqual('bc', first(re.match(regex, 'abc') for regex in ['b.*', 'a(.*)']).group(1))
        self.assertEqual(4, first([1, 1, 3, 4, 5], key=lambda x: x % 2 == 0))

    def test_is_nonstring_iterable(self):
        """Ensure function is_nonstring_iterable works correctly"""
        self.assertEqual(True, is_nonstring_iterable([]))
        self.assertEqual(False, is_nonstring_iterable('test'))
        self.assertEqual(True, is_nonstring_iterable({}))
        self.assertEqual(True, is_nonstring_iterable(()))

    def test_as_text(self):
        """Ensure function as_text works correctly"""
        bad_texts = [3, None, 'test\xd0']
        self.assertEqual('test', as_text(b'test'))
        self.assertEqual('test', as_text('test'))
        with self.assertRaises(ValueError):
            for text in bad_texts:
                as_text(text)

    def test_ensure_list(self):
        """Ensure function ensure_list works correctly"""
        self.assertEqual([], ensure_list([]))
        self.assertEqual(['test'], ensure_list('test'))
        self.assertEqual({}, ensure_list({}))
        self.assertEqual((), ensure_list(()))

    def test_utcparse(self):
        """Ensure function utcparse works correctly"""
        utc_formated_time = '2017-08-31T10:14:02.123456Z'
        self.assertEqual(datetime.datetime(2017, 8, 31, 10, 14, 2, 123456), utcparse(utc_formated_time))

    def test_utcparse_legacy(self):
        """Ensure function utcparse works correctly"""
        utc_formated_time = '2017-08-31T10:14:02Z'
        self.assertEqual(datetime.datetime(2017, 8, 31, 10, 14, 2), utcparse(utc_formated_time))

    def test_backend_class(self):
        """Ensure function backend_class works correctly"""
        self.assertEqual(fixtures.DummyQueue, backend_class(fixtures, 'DummyQueue'))
        self.assertNotEqual(fixtures.say_pid, backend_class(fixtures, 'DummyQueue'))
        self.assertEqual(fixtures.DummyQueue, backend_class(fixtures, 'DummyQueue', override=fixtures.DummyQueue))
        self.assertEqual(
            fixtures.DummyQueue, backend_class(fixtures, 'DummyQueue', override='tests.fixtures.DummyQueue')
        )

    def test_get_redis_version(self):
        """Ensure get_version works properly"""
        redis = Redis()
        self.assertTrue(isinstance(get_version(redis), tuple))

        # Parses 3 digit version numbers correctly
        class DummyRedis(Redis):
            def info(*args):
                return {'redis_version': '4.0.8'}

        self.assertEqual(get_version(DummyRedis()), (4, 0, 8))

        # Parses 3 digit version numbers correctly
        class DummyRedis(Redis):
            def info(*args):
                return {'redis_version': '3.0.7.9'}

        self.assertEqual(get_version(DummyRedis()), (3, 0, 7))

        # Parses 2 digit version numbers correctly (Seen in AWS ElastiCache Redis)
        class DummyRedis(Redis):
            def info(*args):
                return {'redis_version': '7.1'}

        self.assertEqual(get_version(DummyRedis()), (7, 1, 0))

        # Parses 2 digit float version numbers correctly (Seen in AWS ElastiCache Redis)
        class DummyRedis(Redis):
            def info(*args):
                return {'redis_version': 7.1}

        self.assertEqual(get_version(DummyRedis()), (7, 1, 0))

    def test_get_redis_version_gets_cached(self):
        """Ensure get_version works properly"""
        # Parses 3 digit version numbers correctly
        redis = Mock(spec=['info'])
        redis.info = Mock(return_value={'redis_version': '4.0.8'})
        self.assertEqual(get_version(redis), (4, 0, 8))
        self.assertEqual(get_version(redis), (4, 0, 8))
        redis.info.assert_called_once()

    def test_import_attribute(self):
        """Ensure get_version works properly"""
        self.assertEqual(import_attribute('rq.utils.get_version'), get_version)
        self.assertEqual(import_attribute('rq.worker.SimpleWorker'), SimpleWorker)
        self.assertRaises(ValueError, import_attribute, 'non.existent.module')
        self.assertRaises(ValueError, import_attribute, 'rq.worker.WrongWorker')

    def test_ceildiv_even(self):
        """When a number is evenly divisible by another ceildiv returns the quotient"""
        dividend = 12
        divisor = 4
        self.assertEqual(ceildiv(dividend, divisor), dividend // divisor)

    def test_ceildiv_uneven(self):
        """When a number is not evenly divisible by another ceildiv returns the quotient plus one"""
        dividend = 13
        divisor = 4
        self.assertEqual(ceildiv(dividend, divisor), dividend // divisor + 1)

    def test_split_list(self):
        """Ensure split_list works properly"""
        BIG_LIST_SIZE = 42
        SEGMENT_SIZE = 5

        big_list = ['1'] * BIG_LIST_SIZE
        small_lists = list(split_list(big_list, SEGMENT_SIZE))

        expected_small_list_count = ceildiv(BIG_LIST_SIZE, SEGMENT_SIZE)
        self.assertEqual(len(small_lists), expected_small_list_count)

    def test_truncate_long_string(self):
        """Ensure truncate_long_string works properly"""
        assert truncate_long_string('12', max_length=3) == '12'
        assert truncate_long_string('123', max_length=3) == '123'
        assert truncate_long_string('1234', max_length=3) == '123...'
        assert truncate_long_string('12345', max_length=3) == '123...'

        s = 'long string but no max_length provided so no truncating should occur' * 10
        assert truncate_long_string(s) == s

    def test_get_call_string(self):
        """Ensure a case, when func_name, args and kwargs are not None, works properly"""
        cs = get_call_string('f', ('some', 'args', 42), {'key1': 'value1', 'key2': True})
        assert cs == "f('some', 'args', 42, key1='value1', key2=True)"

    def test_get_call_string_with_max_length(self):
        """Ensure get_call_string works properly when max_length is provided"""
        func_name = 'f'
        args = (1234, 12345, 123456)
        kwargs = {'len4': 1234, 'len5': 12345, 'len6': 123456}
        cs = get_call_string(func_name, args, kwargs, max_length=5)
        assert cs == 'f(1234, 12345, 12345..., len4=1234, len5=12345, len6=12345...)'
