#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
    Slixmpp: The Slick XMPP Library
    Copyright (C) 2010  Nathanael C. Fritz
    This file is part of Slixmpp.

    See the file LICENSE for copying permission.
"""

import logging
from getpass import getpass
from argparse import ArgumentParser

import slixmpp

import ssl
from slixmpp.xmlstream import cert


class GTalkBot(slixmpp.ClientXMPP):

    """
    A demonstration of using Slixmpp with accounts from a Google Apps
    account with a custom domain, because it requires custom certificate
    validation.
    """

    def __init__(self, jid, password):
        slixmpp.ClientXMPP.__init__(self, jid, password)

        # The session_start event will be triggered when
        # the bot establishes its connection with the server
        # and the XML streams are ready for use. We want to
        # listen for this event so that we we can initialize
        # our roster.
        self.add_event_handler("session_start", self.start)

        # The message event is triggered whenever a message
        # stanza is received. Be aware that that includes
        # MUC messages and error messages.
        self.add_event_handler("message", self.message)

        # Using a Google Apps custom domain, the certificate
        # does not contain the custom domain, just the GTalk
        # server name. So we will need to process invalid
        # certifcates ourselves and check that it really
        # is from Google.
        self.add_event_handler("ssl_invalid_cert", self.invalid_cert)

    def invalid_cert(self, pem_cert):
        der_cert = ssl.PEM_cert_to_DER_cert(pem_cert)
        try:
            cert.verify('talk.google.com', der_cert)
            logging.debug("CERT: Found GTalk certificate")
        except cert.CertificateError as err:
            logging.error(err.message)
            self.disconnect()

    async def start(self, event):
        """
        Process the session_start event.

        Typical actions for the session_start event are
        requesting the roster and broadcasting an initial
        presence stanza.

        Arguments:
            event -- An empty dictionary. The session_start
                     event does not provide any additional
                     data.
        """
        self.send_presence()
        await self.get_roster()

    def message(self, msg):
        """
        Process incoming message stanzas. Be aware that this also
        includes MUC messages and error messages. It is usually
        a good idea to check the messages's type before processing
        or sending replies.

        Arguments:
            msg -- The received message stanza. See the documentation
                   for stanza objects and the Message stanza to see
                   how it may be used.
        """
        if msg['type'] in ('chat', 'normal'):
            msg.reply("Thanks for sending\n%(body)s" % msg).send()


if __name__ == '__main__':
    # Setup the command line arguments.
    parser = ArgumentParser()

    # Output verbosity options.
    parser.add_argument("-q", "--quiet", help="set logging to ERROR",
                        action="store_const", dest="loglevel",
                        const=logging.ERROR, default=logging.INFO)
    parser.add_argument("-d", "--debug", help="set logging to DEBUG",
                        action="store_const", dest="loglevel",
                        const=logging.DEBUG, default=logging.INFO)

    # JID and password options.
    parser.add_argument("-j", "--jid", dest="jid",
                        help="JID to use")
    parser.add_argument("-p", "--password", dest="password",
                        help="password to use")

    args = parser.parse_args()

    # Setup logging.
    logging.basicConfig(level=args.loglevel,
                        format='%(levelname)-8s %(message)s')

    if args.jid is None:
        args.jid = input("Username: ")
    if args.password is None:
        args.password = getpass("Password: ")

    # Setup the GTalkBot and register plugins. Note that while plugins may
    # have interdependencies, the order in which you register them does
    # not matter.
    xmpp = GTalkBot(args.jid, args.password)
    xmpp.register_plugin('xep_0030') # Service Discovery
    xmpp.register_plugin('xep_0004') # Data Forms
    xmpp.register_plugin('xep_0060') # PubSub
    xmpp.register_plugin('xep_0199') # XMPP Ping

    # Connect to the XMPP server and start processing XMPP stanzas.
    xmpp.connect()
    xmpp.process()
