#
# 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 for Minetest server.
"""

import augeas

from django.urls import reverse_lazy
from django.utils.translation import ugettext_lazy as _

from plinth import actions
from plinth import action_utils
from plinth import cfg
from plinth import frontpage
from plinth import service as service_module
from plinth.menu import main_menu
from plinth.utils import format_lazy


version = 2

service = None

managed_services = ['minetest-server']

managed_packages = ['minetest-server', 'minetest-mod-advspawning',
                    'minetest-mod-animalmaterials', 'minetest-mod-animals',
                    'minetest-mod-mesecons', 'minetest-mod-mobf-core',
                    'minetest-mod-mobf-trap', 'minetest-mod-moreblocks',
                    'minetest-mod-nether', 'minetest-mod-torches']

name = _('Minetest')

short_description = _('Block Sandbox')

description = [
    format_lazy(
        _('Minetest is a multiplayer infinite-world block sandbox. This '
          'module enables the Minetest server to be run on this '
          '{box_name}, on the default port (30000). To connect to the server, '
          'a <a href="http://www.minetest.net/downloads/">Minetest client</a> '
          'is needed.'), box_name=_(cfg.box_name)),
]

reserved_usernames = ['Debian-minetest']

CONFIG_FILE = '/etc/minetest/minetest.conf'
AUG_PATH = '/files' + CONFIG_FILE + '/.anon'


def init():
    """Initialize the module."""
    menu = main_menu.get('apps')
    menu.add_urlname(name, 'glyphicon-th-large', 'minetest:index', short_description)

    global service
    setup_helper = globals()['setup_helper']
    if setup_helper.get_state() != 'needs-setup':
        service = service_module.Service(
            managed_services[0], name,
            ports=['minetest-plinth'], is_external=True, enable=enable,
            disable=disable)

        if service.is_enabled():
            add_shortcut()


def setup(helper, old_version=None):
    """Install and configure the module."""
    helper.install(managed_packages)
    global service
    if service is None:
        service = service_module.Service(
            managed_services[0], name,
            ports=['minetest-plinth'], is_external=True, enable=enable,
            disable=disable)
    helper.call('post', service.notify_enabled, None, True)
    helper.call('post', add_shortcut)


def add_shortcut():
    frontpage.add_shortcut('minetest', name, url=None,
                           short_description=short_description,
                           details=description,
                           configure_url=reverse_lazy('minetest:index'),
                           login_required=False)


def enable():
    """Enable the module."""
    actions.superuser_run('service', ['enable', managed_services[0]])
    add_shortcut()


def disable():
    """Disable the module."""
    actions.superuser_run('service', ['disable', managed_services[0]])
    frontpage.remove_shortcut('minetest')


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

    results.append(action_utils.diagnose_port_listening(30000, 'udp4'))

    return results


def load_augeas():
    """Initialize Augeas."""
    aug = augeas.Augeas(flags=augeas.Augeas.NO_LOAD +
                        augeas.Augeas.NO_MODL_AUTOLOAD)
    aug.set('/augeas/load/Php/lens', 'Php.lns')
    aug.set('/augeas/load/Php/incl[last() + 1]', CONFIG_FILE)
    aug.load()
    return aug


def get_max_players(aug):
    """Return the maximum players allowed on the server at one time."""
    value = aug.get(AUG_PATH + '/max_users')
    if value:
        return int(value)


def is_creative_mode_enabled(aug):
    """Return whether creative mode is enabled."""
    value = aug.get(AUG_PATH + '/creative_mode')
    return value == 'true'


def is_pvp_enabled(aug):
    """Return whether PVP is enabled."""
    value = aug.get(AUG_PATH + '/enable_pvp')
    return value == 'true'


def is_damage_enabled(aug):
    """Return whether damage is enabled."""
    value = aug.get(AUG_PATH + '/enable_damage')
    return value == 'true'


def get_configuration():
    """Return the current configuration."""
    aug = load_augeas()
    conf = {
        'max_players': get_max_players(aug),
        'creative_mode': is_creative_mode_enabled(aug),
        'enable_pvp': is_pvp_enabled(aug),
        'enable_damage': is_damage_enabled(aug),
    }
    return conf
