#
# This file is part of Plinth.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

"""
Plinth module to configure system date and time
"""

from django.utils.translation import ugettext_lazy as _
import subprocess

from plinth import action_utils
from plinth import cfg
from plinth import service as service_module


depends = ['system']

service = None


def init():
    """Intialize the date/time module."""
    menu = cfg.main_menu.get('system:index')
    menu.add_urlname(_('Date & Time'), 'glyphicon-time',
                     'datetime:index', 900)

    global service
    service = service_module.Service(
        'ntp', _('Network Time Server'),
        is_external=False, enabled=is_enabled())


def is_enabled():
    """Return whether the module is enabled."""
    return action_utils.service_is_enabled('ntp')


def is_running():
    """Return whether the service is running."""
    return action_utils.service_is_running('ntp')


def diagnose():
    """Run diagnostics and return the results."""
    results = []
    results.append(_diagnose_ntp_server_count())

    return results


def _diagnose_ntp_server_count():
    """Diagnose minimum NTP server count."""
    result = 'failed'
    try:
        output = subprocess.check_output(['ntpq', '-n', '-c', 'lpeers'])
        if len(output.decode().splitlines()[2:]):
            result = 'passed'
    except subprocess.CalledProcessError:
        pass

    return [_('NTP client in contact with servers'), result]