"""Unit tests for utils timezone module."""

from datetime import datetime

import pytest
import pytz

from src.constants import common_consts
from src.constants import timezones as tz_const
from src.utils import timezone


def get_date(hours=12, timezone_name=None):
    """Get test datetime.

    Args:
        hours (int): hours in test date (<24)
        timezone_name (str): local timezone
    Returns:
        datetime: UTC test date or in local timezone
    """
    date = datetime(2018, 1, 1, hours, 0, 0, tzinfo=pytz.utc)
    if timezone_name:
        tz = pytz.timezone(timezone_name)
        date = date.astimezone(tz)
    return date.replace(tzinfo=None)


@pytest.mark.parametrize(
    'local_date, timezone_name, expected_result',
    (
        (get_date(), str(pytz.utc), get_date()),
        (get_date(timezone_name=tz_const.US_EASTERN), tz_const.US_EASTERN,
         get_date())
    )
)
def test_convert_to_utc_datetime(local_date, timezone_name, expected_result):
    """Test for convert_to_utc function."""
    result = timezone.convert_to_utc_datetime(local_date, timezone_name)
    assert result == expected_result


@pytest.mark.parametrize(
    'local_date, passed_local_date, to_utc_datetime_return_value, '
    'expected_result, func_called',
    (
        (
            get_date(),
            # string
            get_date().strftime(common_consts.DYNAMODB_DATETIME_FORMAT),
            get_date(hours=2),
            get_date(hours=2).strftime(common_consts.OUTPUT_DATETIME_FORMAT),
            True
        ),
        (
            get_date(),
            # string
            get_date().strftime(common_consts.MAXWELLS_DATETIME_FORMAT),
            get_date(hours=2),
            get_date(hours=2).strftime(
                common_consts.OUTPUT_DATETIME_FORMAT),
            True
        ),
        (
            get_date(),
            # datetime
            get_date(),
            get_date(hours=2),
            get_date(hours=2).strftime(common_consts.OUTPUT_DATETIME_FORMAT),
            True
        ),
        (None, None, None, None, False)
    )
)
def test_convert_to_utc_str(
        local_date, passed_local_date, to_utc_datetime_return_value,
        expected_result, func_called, mocker):
    """Test for convert_to_utc_str function."""
    timezone_name = 'tz'
    mocked_convert_to_utc = mocker.patch(
        'src.utils.timezone.convert_to_utc_datetime')
    mocked_convert_to_utc.return_value = to_utc_datetime_return_value
    result = timezone.convert_to_utc_str(passed_local_date, timezone_name)
    assert result == expected_result
    assert mocked_convert_to_utc.call_count == func_called
    if func_called:
        assert mocked_convert_to_utc.call_args[0] == (
            local_date, timezone_name)


def test_convert_to_utc_str_raises(mocker):
    """Test for convert_to_utc_str function."""
    mocked_convert_to_utc = mocker.patch(
        'src.utils.timezone.convert_to_utc_datetime')
    with pytest.raises(ValueError):
        timezone.convert_to_utc_str('funky date', 'tz')
    assert mocked_convert_to_utc.call_count == 0