#!/usr/bin/env python
#
#  mmvirtdlv -- MailMan Virtual Deliver
#
#  Sean Reifschneider, tummy.com, ltd.  <jafo-mmvirtdlv@tummy.com>
#  Copyright, tummy.com, ltd.  All Rights Reserved
#
#  The current version of this program is for QMail only.
#
#  The idea behind mmvirtdel is to allow automatic detection of new
#  mailman mailing lists.  It uses the "EXT" environment variables
#  as provided by QMail to determine the name of the list and the
#  function (request, owner, post).  If it can't determine the name
#  of the list or there is an invalid function specified, the message
#  is run through "forwardCmd" (default, forward to mailman-owner).
#
#  Setup:
#    Change "mailmanHome" to the home directory for mailman.
#      ("lists/<listname>" and "mail/wrapper" must exist under that directory)
#    Go to the mailman home directory and create ".qmail-default" containing:
#      |/path/to/mmvirtdel
#    Make sure that mail for "list" is now sent to "mailman-domain.com-list":
#      Add "lists.domain.com:mailman-lists.domain.com" to
#          "/var/qmail/control/virtualdomains"
#      Set up the appropriate alias files which forward the mail to
#        "mailman-domain.com-list" (though that's what we're trying to get
#        away from)

mailmanHome = '/home/mailman'
forwardCmd = '/var/qmail/forward mailman-owner'

destList = { 'owner' : 'mailowner %s', 'request' : 'mailcmd %s',
		'admin' : 'mailowner %s', 'list' : 'post %s' }

import os
import string


##############
def getExts():
	'''Return a list of the extensions.  Doing a string.join(list, '-') should
	result in the full extension of the local address.'''
	def addExt(l, e):
		s = os.environ.get(e, None)
		if s:	
			rstrip = string.join(l, '-')
			if len(s) >= len(rstrip) and s[-len(rstrip):] == rstrip:
				s = s[:-(len(rstrip) + 1)]
			l.insert(0, s)
	
	l = []
	addExt(l, 'EXT4')
	addExt(l, 'EXT3')
	addExt(l, 'EXT2')
	addExt(l, 'EXT')

	return(l)

################################
#  determine destination of list
extList = getExts()
destName = extList[1]
destCmd = None

#  <domain> <listname>
if len(extList) == 2: destType = destList.get('list', None)
#  <domain> <listname> <suffix>
if len(extList) == 3: destType = destList.get(extList[2], None)

#  if unknown destination, send to mailman-owner
if not destType:
	destCmd = forwardCmd

#  check for list existance
if not destCmd:
	destDir = os.path.join(mailmanHome, 'lists', destName)
	if not os.path.exists(destDir):
		destCmd = forwardCmd

#  otherwise, create "forward to list" command
if not destCmd:
	destCmd = os.path.join(mailmanHome, 'mail', 'wrapper')
	destCmd = destCmd + ' ' + (destType % destName)

ret = os.system(destCmd)
os.exit(ret)