#
# This file is part of FreedomBox.
#
# 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/>.
#
"""
FreedomBox app for service discovery.
"""

from django.utils.translation import ugettext_lazy as _

from plinth import actions
from plinth import app as app_module
from plinth import cfg, menu
from plinth.daemon import Daemon
from plinth.modules.firewall.components import Firewall
from plinth.utils import format_lazy
from plinth.views import AppView

from .manifest import backup

# pylint: disable=C0103

version = 1

is_essential = True

managed_services = ['avahi-daemon']

managed_packages = ['avahi-daemon', 'avahi-utils']

name = _('Service Discovery')

description = [
    format_lazy(
        _('Service discovery allows other devices on the network to '
          'discover your {box_name} and services running on it.  It '
          'also allows {box_name} to discover other devices and '
          'services running on your local network.  Service discovery is '
          'not essential and works only on internal networks.  It may be '
          'disabled to improve security especially when connecting to a '
          'hostile local network.'), box_name=_(cfg.box_name))
]

manual_page = 'ServiceDiscovery'

app = None


class AvahiApp(app_module.App):
    """FreedomBox app for Avahi."""

    app_id = 'avahi'

    def __init__(self):
        """Create components for the app."""
        super().__init__()
        menu_item = menu.Menu('menu-avahi', name, None, 'fa-compass',
                              'avahi:index', parent_url_name='system')
        self.add(menu_item)

        firewall = Firewall('firewall-avahi', name, ports=['mdns'],
                            is_external=False)
        self.add(firewall)

        daemon = Daemon('daemon-avahi', managed_services[0])
        self.add(daemon)


def init():
    """Intialize the service discovery module."""
    global app
    app = AvahiApp()
    if app.is_enabled():
        app.set_enabled(True)


def setup(helper, old_version=None):
    """Install and configure the module."""
    helper.install(managed_packages)
    # Reload avahi-daemon now that first-run does not reboot. After performing
    # FreedomBox Service (Plinth) package installation, new Avahi files will be
    # available and require restart.
    helper.call('post', actions.superuser_run, 'service',
                ['reload', 'avahi-daemon'])


class AvahiAppView(AppView):
    app_id = 'avahi'
    name = name
    description = description
    manual_page = manual_page