# This file is part of Gajim.
#
# Gajim is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published
# by the Free Software Foundation; version 3 only.
#
# Gajim 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Gajim.  If not, see <http://www.gnu.org/licenses/>.

# XEP-0199: XMPP Ping

from typing import Any
from typing import Tuple

import logging
import time

import nbxmpp
from gi.repository import GLib

from gajim.common import app
from gajim.common.nec import NetworkIncomingEvent
from gajim.common.types import ConnectionT
from gajim.common.types import ContactsT

log = logging.getLogger('gajim.c.m.ping')


class Ping:
    def __init__(self, con: ConnectionT) -> None:
        self._con = con
        self._account = con.name
        self._timeout_id = None

        self.handlers = [
            ('iq', self._answer_request, 'get', nbxmpp.NS_PING),
        ]

    @staticmethod
    def _get_ping_iq(to: str) -> nbxmpp.Iq:
        iq = nbxmpp.Iq('get', to=to)
        iq.addChild(name='ping', namespace=nbxmpp.NS_PING)
        return iq

    def send_keepalive_ping(self) -> None:
        if not app.account_is_connected(self._account):
            return

        log.info('Send keepalive')

        seconds = app.config.get_per('accounts', self._account,
                                     'time_for_ping_alive_answer')
        self._timeout_id = GLib.timeout_add_seconds(seconds, self._reconnect)

        to = app.config.get_per('accounts', self._account, 'hostname')
        self._con.connection.SendAndCallForResponse(self._get_ping_iq(to),
                                                    self._keepalive_received)

    def _keepalive_received(self, _stanza: nbxmpp.Iq) -> None:
        log.info('Received keepalive')
        self.remove_timeout()

    def _reconnect(self) -> None:
        if not app.account_is_connected(self._account):
            return
        # We haven't got the pong in time, disco and reconnect
        log.warning('No reply received for keepalive ping. Reconnecting...')
        self._con.disconnect(immediately=True)

    def send_ping(self, contact: ContactsT) -> None:
        if not app.account_is_connected(self._account):
            return

        to = contact.get_full_jid()
        iq = self._get_ping_iq(to)

        log.info('Send ping to %s', to)

        self._con.connection.SendAndCallForResponse(
            iq, self._pong_received, {'ping_time': time.time(),
                                      'contact': contact})

        app.nec.push_incoming_event(
            PingSentEvent(None, conn=self._con, contact=contact))

    def _pong_received(self,
                       _con: ConnectionT,
                       stanza: nbxmpp.Iq,
                       ping_time: int,
                       contact: ContactsT) -> None:
        if not nbxmpp.isResultNode(stanza):
            log.info('Error: %s', stanza.getError())
            app.nec.push_incoming_event(
                PingErrorEvent(None, conn=self._con, contact=contact))
            return
        diff = round(time.time() - ping_time, 2)
        log.info('Received pong from %s after %s seconds',
                 stanza.getFrom(), diff)
        app.nec.push_incoming_event(
            PingReplyEvent(None, conn=self._con,
                           contact=contact,
                           seconds=diff))

    def _answer_request(self,
                        _con: ConnectionT,
                        stanza: nbxmpp.Iq) -> None:
        iq = stanza.buildReply('result')
        ping = iq.getTag('ping')
        if ping is not None:
            iq.delChild(ping)
        self._con.connection.send(iq)
        log.info('Send pong to %s', stanza.getFrom())
        raise nbxmpp.NodeProcessed

    def remove_timeout(self) -> None:
        if self._timeout_id is None:
            return
        log.info('Remove ping timeout')
        GLib.source_remove(self._timeout_id)
        self._timeout_id = None

    def cleanup(self) -> None:
        self.remove_timeout()


class PingSentEvent(NetworkIncomingEvent):
    name = 'ping-sent'


class PingReplyEvent(NetworkIncomingEvent):
    name = 'ping-reply'


class PingErrorEvent(NetworkIncomingEvent):
    name = 'ping-error'


def get_instance(*args: Any, **kwargs: Any) -> Tuple[Ping, str]:
    return Ping(*args, **kwargs), 'Ping'