# Copyright (C) 2000-2008 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.

"""Outgoing queue runner."""

import os
import sys
import copy
import time
import email
import socket
import logging

from Mailman import Errors
from Mailman import Message
from Mailman.configuration import config
from Mailman.queue import Runner, Switchboard
from Mailman.queue.bounce import BounceMixin

# This controls how often _doperiodic() will try to deal with deferred
# permanent failures.  It is a count of calls to _doperiodic()
DEAL_WITH_PERMFAILURES_EVERY = 10

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



class OutgoingRunner(Runner, BounceMixin):
    QDIR = config.OUTQUEUE_DIR

    def __init__(self, slice=None, numslices=1):
        Runner.__init__(self, slice, numslices)
        BounceMixin.__init__(self)
        # We look this function up only at startup time
        handler = config.handlers[config.DELIVERY_MODULE]
        self._func = handler.process
        # This prevents smtp server connection problems from filling up the
        # error log.  It gets reset if the message was successfully sent, and
        # set if there was a socket.error.
        self._logged = False
        self._retryq = Switchboard(config.RETRYQUEUE_DIR)

    def _dispose(self, mlist, msg, msgdata):
        # See if we should retry delivery of this message again.
        deliver_after = msgdata.get('deliver_after', 0)
        if time.time() < deliver_after:
            return True
        # Make sure we have the most up-to-date state
        mlist.Load()
        try:
            pid = os.getpid()
            self._func(mlist, msg, msgdata)
            # Failsafe -- a child may have leaked through.
            if pid <> os.getpid():
                log.error('child process leaked thru: %s', modname)
                os._exit(1)
            self._logged = False
        except socket.error:
            # There was a problem connecting to the SMTP server.  Log this
            # once, but crank up our sleep time so we don't fill the error
            # log.
            port = config.SMTPPORT
            if port == 0:
                port = 'smtp'
            # Log this just once.
            if not self._logged:
                log.error('Cannot connect to SMTP server %s on port %s',
                          config.SMTPHOST, port)
                self._logged = True
            return True
        except Errors.SomeRecipientsFailed, e:
            # Handle local rejects of probe messages differently.
            if msgdata.get('probe_token') and e.permfailures:
                self._probe_bounce(mlist, msgdata['probe_token'])
            else:
                # Delivery failed at SMTP time for some or all of the
                # recipients.  Permanent failures are registered as bounces,
                # but temporary failures are retried for later.
                #
                # BAW: msg is going to be the original message that failed
                # delivery, not a bounce message.  This may be confusing if
                # this is what's sent to the user in the probe message.  Maybe
                # we should craft a bounce-like message containing information
                # about the permanent SMTP failure?
                if e.permfailures:
                    self._queue_bounces(mlist.fqdn_listname, e.permfailures,
                                        msg)
                # Move temporary failures to the qfiles/retry queue which will
                # occasionally move them back here for another shot at
                # delivery.
                if e.tempfailures:
                    now = time.time()
                    recips = e.tempfailures
                    last_recip_count = msgdata.get('last_recip_count', 0)
                    deliver_until = msgdata.get('deliver_until', now)
                    if len(recips) == last_recip_count:
                        # We didn't make any progress, so don't attempt
                        # delivery any longer.  BAW: is this the best
                        # disposition?
                        if now > deliver_until:
                            return False
                    else:
                        # Keep trying to delivery this message for a while
                        deliver_until = now + config.DELIVERY_RETRY_PERIOD
                    msgdata['last_recip_count'] = len(recips)
                    msgdata['deliver_until'] = deliver_until
                    msgdata['recips'] = recips
                    self._retryq.enqueue(msg, msgdata)
        # We've successfully completed handling of this message
        return False

    _doperiodic = BounceMixin._doperiodic

    def _cleanup(self):
        BounceMixin._cleanup(self)
        Runner._cleanup(self)