#!/usr/bin/python

###
###  This script is used to get lists of LISTSERV subscribers for a
###  given list, who have a certain option set, and reformat the
###  resulting email to match the format of the Mailman "who" command,
###  which then allows the add_members script to take this file as
###  input.
###
###  It is thus primarily useful as part of migrating subscribers from
###  old Listserv lists to new Mailman lists, while trying to preserve
###  their options.
###
###  For example, you could email LISTSERV a command like
###  "QUERY listname with DIGEST FOR *@*" (or NODIGEST, NOMAIL, etc.)
###  and then use a procmail filter to send the email reply into this
###  script, which will save it into a file called digest-listname.txt
###  in the directory specified by the savedir variable below.
###
###  Then you could run the Mailman bin command
###  add_members -d digest-listname.txt listname
###  to subscribe the members in that file to the new list with their
###  digest option already set.
###
###  An example procmail filter to send the LISTSERV command results
###  into this script might be something like the following:
###
###  :0
###  * ^From:.*LISTSERV@
###  * ^Subject:.*Re:.* query
###  | cat - | $HOME/.procmail/save_opt_query.py
###
###  See the queryopt.pl script for a programmatic way to generate
###  the LISTSERV emails which query lists for subscriber options.
###
###  Anthony R. Thompson - Dec 2009
###  Contact: put @ between art and sigilservices.com
###
###  Copyright (C) 1998-2010 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. http://www.fsf.org/licensing/licenses/gpl.html
###

import email, re, sys

# This has to be hard-coded because procmail doesn't have our environment
savedir = '/path/to/place/to/save/outputfiles'       # INSTALL

from cStringIO import StringIO # needed later for faster string append
  # See http://www.skymind.com/~ocrow/python_string/ for more info
def list_to_string(list):
    file_str = StringIO()
    for item in list: file_str.write(str(item))
    return file_str.getvalue()

msg = email.message_from_string(list_to_string(sys.stdin.readlines()))
subject = msg.get('Subject')
body = msg.get_payload()

# Get type of digest query from subject line (digest or nodigest)
# Example subject line is Re: DIGEST query
# Note that subject of incoming message is Re: subject of command msg
opttype = re.sub('^Re: ', '', subject)
opttype = re.sub(' query.*', '', opttype)
opttype = opttype.lower()
if (opttype not in ['digest', 'nodigest', 'mail', 'nomail', 'mime', 'nomime',
                    'conceal', 'review', 'noreview', 'post', 'nopost',
                    'repro', 'norepro', 'subjecthdr', 'editor']):
    err = 'Unknown option type from subject line: ' + opttype
    raise ValueError(err)

# Convert body to a list, if necessary
if (type(body) is str):
    mail_body = re.split('\n', msg.get_payload())
elif (type(body) is list):
    mail_body = body
else:
    err = 'Unknown object type from get_payload() - neither list nor string'
    raise ValueError(err)

# Now go through the body and gather up the info we need, incl list name
listname = ''
sublines = []
for line in mail_body:

    if (re.search('^> QUERY', line)):
        listname = re.sub('^> QUERY ', '', line)
        listname = re.sub(' .*', '', listname)
        listname = listname.lower()

    elif (re.search('^Subscription options', line)):
        subinfo = re.sub('^Subscription options for ', '', line)
        subinfo = re.sub('>,.*', '>', subinfo)
        sublines.append(subinfo)

if (listname == ''):
    print "Unable to obtain list name from email body - exiting"
    sys.exit(1)

# Overwrite existing file with results of this command
outfile = open("%s/%s-%s.txt" % (savedir, opttype, listname), 'w')
for line in sublines:
    outfile.write(line)
    outfile.write("\n")
outfile.close()