# Copyright (C) 2007-2014 by the Free Software Foundation, Inc.
#
# This file is part of GNU Mailman.
#
# GNU Mailman 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, either version 3 of the License, or (at your option)
# any later version.
#
# GNU Mailman 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
# GNU Mailman.  If not, see <http://www.gnu.org/licenses/>.

"""Sending notifications."""

from __future__ import absolute_import, print_function, unicode_literals

__metaclass__ = type
__all__ = [
    'send_admin_subscription_notice',
    'send_goodbye_message',
    'send_welcome_message',
    ]


import logging

from email.utils import formataddr
from lazr.config import as_boolean
from mailman.config import config
from mailman.core.i18n import _
from mailman.email.message import OwnerNotification, UserNotification
from mailman.interfaces.member import DeliveryMode
from mailman.interfaces.templates import ITemplateLoader
from mailman.utilities.i18n import make
from mailman.utilities.string import expand, wrap
from six.moves.urllib_error import URLError
from zope.component import getUtility


log = logging.getLogger('mailman.error')



def _get_message(uri_template, mlist, language):
    if not uri_template:
        return ''
    try:
        uri = expand(uri_template, dict(
            listname=mlist.fqdn_listname,
            language=language.code,
            ))
        message = getUtility(ITemplateLoader).get(uri)
    except URLError:
        log.exception('Message URI not found ({0}): {1}'.format(
            mlist.fqdn_listname, uri_template))
        return ''
    else:
        return wrap(message)



def send_welcome_message(mlist, member, language, text=''):
    """Send a welcome message to a subscriber.

    Prepending to the standard welcome message template is the mailing list's
    welcome message, if there is one.

    :param mlist: The mailing list.
    :type mlist: IMailingList
    :param member: The member to send the welcome message to.
    :param address: IMember
    :param language: The language of the response.
    :type language: ILanguage
    """
    welcome_message = _get_message(mlist.welcome_message_uri, mlist, language)
    options_url = member.options_url
    # Get the text from the template.
    display_name = ('' if member.user is None else member.user.display_name)
    text = expand(welcome_message, dict(
        fqdn_listname=mlist.fqdn_listname,
        list_name=mlist.display_name,
        listinfo_uri=mlist.script_url('listinfo'),
        list_requests=mlist.request_address,
        user_name=display_name,
        user_address=member.address.email,
        user_options_uri=options_url,
        ))
    digmode = ('' if member.delivery_mode is DeliveryMode.regular
               else _(' (Digest mode)'))
    msg = UserNotification(
        formataddr((display_name, member.address.email)),
        mlist.request_address,
        _('Welcome to the "$mlist.display_name" mailing list${digmode}'),
        text, language)
    msg['X-No-Archive'] = 'yes'
    msg.send(mlist, verp=as_boolean(config.mta.verp_personalized_deliveries))



def send_goodbye_message(mlist, address, language):
    """Send a goodbye message to a subscriber.

    Prepending to the standard goodbye message template is the mailing list's
    goodbye message, if there is one.

    :param mlist: the mailing list
    :type mlist: IMailingList
    :param address: The address to respond to
    :type address: string
    :param language: the language of the response
    :type language: string
    """
    goodbye_message = _get_message(mlist.goodbye_message_uri,
                                   mlist, language)
    msg = UserNotification(
        address, mlist.bounces_address,
        _('You have been unsubscribed from the $mlist.display_name '
          'mailing list'),
        goodbye_message, language)
    msg.send(mlist, verp=as_boolean(config.mta.verp_personalized_deliveries))



def send_admin_subscription_notice(mlist, address, display_name, language):
    """Send the list administrators a subscription notice.

    :param mlist: The mailing list.
    :type mlist: IMailingList
    :param address: The address being subscribed.
    :type address: string
    :param display_name: The name of the subscriber.
    :type display_name: string
    :param language: The language of the address's display name.
    :type language: string
    """
    with _.using(mlist.preferred_language.code):
        subject = _('$mlist.display_name subscription notification')
    display_name = display_name.encode(language.charset, 'replace')
    text = make('adminsubscribeack.txt',
                mailing_list=mlist,
                listname=mlist.display_name,
                member=formataddr((display_name, address)),
                )
    msg = OwnerNotification(mlist, subject, text, roster=mlist.administrators)
    msg.send(mlist)