# Copyright (C) 1998-2008 by the Free Software Foundation, Inc.
#
# This program 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 2
# 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
# USA.

"""Cleanse certain headers from all messages."""

__metaclass__ = type
__all__ = ['Cleanse']


import logging

from email.Utils import formataddr
from zope.interface import implements

from Mailman.i18n import _
from Mailman.interfaces import IHandler
from Mailman.pipeline.cook_headers import uheader


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



class Cleanse:
    """Cleanse certain headers from all messages."""

    implements(IHandler)

    name = 'cleanse'
    description = _('Cleanse certain headers from all messages.')

    def process(self, mlist, msg, msgdata):
        """See `IHandler`."""
        # Remove headers that could contain passwords.
        del msg['approved']
        del msg['approve']
        del msg['urgent']
        # We remove other headers from anonymous lists.
        if mlist.anonymous_list:
            log.info('post to %s from %s anonymized',
                     mlist.fqdn_listname, msg.get('from'))
            del msg['from']
            del msg['reply-to']
            del msg['sender']
            # Hotmail sets this one
            del msg['x-originating-email']
            i18ndesc = str(uheader(mlist, mlist.description, 'From'))
            msg['From'] = formataddr((i18ndesc, mlist.posting_address))
            msg['Reply-To'] = mlist.posting_address
        # Some headers can be used to fish for membership.
        del msg['return-receipt-to']
        del msg['disposition-notification-to']
        del msg['x-confirm-reading-to']
        # Pegasus mail uses this one... sigh.
        del msg['x-pmrqc']
        # Don't let this header be spoofed.  See RFC 5064.
        del msg['archived-at']