#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""News to mail gateway script. Copyright 2000 Cosimo Alfarano

Author: Cosimo Alfarano
Date: June 11 2000

pygs - Copyright 2000 by Cosimo Alfarano <Alfarano@Students.CS.UniBo.It>
You can use this software under the terms of the GPL. If we meet some day,
and you think this stuff is worth it, you can buy me a beer in return.

Thanks to md for this useful formula. Beer is beer.

Gets news article from stdin and sends it via SMTP.
"""
from __future__ import print_function
import sys
import os
import argparse

sys.path.append('/usr/lib/pyg')

import whitelist
import news2mail
from mail2news import VERSION, DESC


def parse_cmdline():
    """
    set a dictionary with smtp new header in gw parameter (gw.smtpheads)
    return (test,verbose) boolean tuple
    """
    parser = argparse.ArgumentParser(
        description='pyg version %s - Copyright 2000 Cosimo Alfarano\n%s' %
        (VERSION, DESC))

    parser.add_argument('-H', '--smtpserver', default='')
    parser.add_argument('-s', '--sender', required=True, default='')
    parser.add_argument('-e', '--envelope', default='')
    parser.add_argument('-t', '--to', dest='rcpt', required=True)
    parser.add_argument('-w', '--wlfile')
    parser.add_argument('-l', '--logfile')

    parser.add_argument('-T', '--test',
                        help='test mode (not send article via SMTP)',
                        action='store_true')
    parser.add_argument('-d', '--debug',
                        action='store_true')
    parser.add_argument('-V', '--verbose', help='verbose output',
                        action='store_true')

    opts = parser.parse_args()

#  By rfc822 [Resent-]Sender: should be ever set, unless == From:
# (not this case). Should be a human, while [Resent-]From: may be a program.

    if opts.rcpt == '' or opts.sender == '':
        raise argparse.ArgumentError('missing command line option')

    if opts.envelope == '' and opts.sender != '':
        opts.envelope = opts.sender

    return opts


"""main is structured in 4 phases:
    1) check and set pyg's internal variables
    2) check whitelist for users' permission
    3) format rfc 822 headers from input article
    4) open smtp connection and send e-mail
"""

try:

    """phase 1:
    check and set pyg's internal variables
    """

    n2m = news2mail.news2mail()
    owner = None

    # it returns only test, other parms are set directly in the actual
    # parameter
    args = parse_cmdline()

    # check if n2m has some file prefercences set on commandline
    if args.wlfile is None:
        wl = os.path.expanduser('~/pyg.whitelist')
    else:
        wl = args.wlfile

    if args.logfile is None:
        log = os.path.expanduser('~/pyg.log')
    else:
        log = args.logfile

#     print 'using %s %s\n' % (wl,log)

    wl = whitelist.whitelist(wl, log)

    # reads stdin and parses article separating head from body
    n2m.readfile()

    """phase 2:
    check whitelist for user's permission
    """

    # make a first check of From: address
    owner = wl.checkfrom(n2m.message['From'])
    if owner is None:
        if sys.stdin.isatty() == 1 or args.test:
            print ('"%s" is not in whitelist!' % (n2m.message['From'][:-1]))
        else:
            wl.logmsg(n2m.nntpheads, wl.DENY)

        # if verbose, I want to print out headers, so I can't
        # exit now.
        if not args.verbose:
            sys.exit(1)

    """phase 3:
    format rfc 822 headers from input article
    """

    n2m.addheads()  # add some important heads
    n2m.renameheads()  # rename useless heads
    n2m.removeheads()  # remove other heads

    n2m.sortheads()  # sort remaining heads :)

    # prints formatted email message only (without send) if user wants
    if args.verbose:
        print(n2m.message.as_string())

    if owner is None:
        sys.exit(1)

    """phase 4:
    open smtp connection and send e-mail
    """

    if len(n2m.headers) > 0:
        wl.logmsg(n2m.heads_dict, wl.ACCEPT, owner)
        if not args.test:
            n2m.sendarticle()
    else:
        print('Error: No Headers!!!')

except KeyboardInterrupt:
    print('Keyboard Interrupt')
    sys.exit(1)