import datetime
import unittest.mock

import dbus
import pytest

import systemctl_mqtt

_UTC = datetime.timezone(offset=datetime.timedelta(seconds=0))

# pylint: disable=protected-access


def test__get_login_manager():
    login_manager = systemctl_mqtt._get_login_manager()
    assert isinstance(login_manager, dbus.proxies.Interface)
    assert login_manager.dbus_interface == "org.freedesktop.login1.Manager"
    # https://freedesktop.org/wiki/Software/systemd/logind/
    assert isinstance(login_manager.CanPowerOff(), dbus.String)


@pytest.mark.parametrize("action", ["poweroff", "reboot"])
def test__schedule_shutdown(action):
    login_manager_mock = unittest.mock.MagicMock()
    with unittest.mock.patch(
        "systemctl_mqtt._get_login_manager", return_value=login_manager_mock
    ):
        systemctl_mqtt._schedule_shutdown(action=action)
    login_manager_mock.ScheduleShutdown.assert_called_once()
    schedule_args, schedule_kwargs = login_manager_mock.ScheduleShutdown.call_args
    assert len(schedule_args) == 2
    assert schedule_args[0] == action
    shutdown_datetime = datetime.datetime.fromtimestamp(
        schedule_args[1] / 10 ** 6, tz=_UTC,
    )
    delay = shutdown_datetime - datetime.datetime.now(tz=_UTC)
    assert delay.total_seconds() == pytest.approx(
        datetime.timedelta(seconds=4).total_seconds(), abs=0.1,
    )
    assert not schedule_kwargs


@pytest.mark.parametrize(
    ("topic_suffix", "expected_action_arg"), [("poweroff", "poweroff")]
)
def test_mqtt_topic_suffix_action_mapping(topic_suffix, expected_action_arg):
    action = systemctl_mqtt._MQTT_TOPIC_SUFFIX_ACTION_MAPPING[topic_suffix]
    login_manager_mock = unittest.mock.MagicMock()
    with unittest.mock.patch(
        "systemctl_mqtt._get_login_manager", return_value=login_manager_mock
    ):
        action()
    login_manager_mock.ScheduleShutdown.assert_called_once()
    schedule_args, schedule_kwargs = login_manager_mock.ScheduleShutdown.call_args
    assert len(schedule_args) == 2
    assert schedule_args[0] == expected_action_arg
    assert not schedule_kwargs