#!/usr/bin/env python

"""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.
"""

import sys, os
import getopt
from string import split

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

import pyginfo
import whitelist
import news2mail
#import mail2news

	
def parse_cmdline(gw):
	"""Parses cmdline with getopt.
	set a dictionary with smtp new header in gw parameter (gw.smtpheads)
	return (test,verbose) boolean tuple 
	"""

	opt, arg = None, None
	test, verbose = 0, 0
	retnull = (None, None)
	
	try:
		opt, arg = getopt.getopt(sys.argv[1:],"H:t:s:e:w:l:hdvVT")
	except (getopt.error), message:
		print '%s: %s\n' % (sys.argv[0], message)
		sys.exit(1)
	
	if len(sys.argv) == 1 or opt == []:
		gw.smtpheads = None
		return retnull
	
	for i in range(len(opt)):
		if opt[i][0] == '-h':
			gw.smtpheads = None
			return retnull
		elif opt[i][0] == '-v':
			gw.smtpheads = None
			return retnull
		elif opt[i][0] == '-H':
			gw.smtpserver = opt[i][1]
		elif opt[i][0] == '-s':
			gw.smtpheads['Resent-Sender:'] = opt[i][1] + '\n'
			gw.sender = opt[i][1]
		elif opt[i][0] == '-t' or opt[i][0] == '-r':
			gw.smtpheads['To:'] = opt[i][1] + '\n'
			gw.rcpt = opt[i][1]
		elif opt[i][0] == '-e':
			gw.smtpheads['Resent-From:'] = opt[i][1] +  '\n' #envelope
			gw.envelope = opt[i][1]
		elif opt[i][0] == '-w':
			gw.wlfile = opt[i][1]
		elif opt[i][0] == '-l':
			gw.logfile = opt[i][1]
		elif opt[i][0] == '-d':
			gw.debug = 1
		elif opt[i][0] == '-T':
			test = 1
		elif opt[i][0] == '-V':
			verbose = 1

#  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 gw.rcpt == '' or gw.sender == '':
		print 'missing command line option'
		gw.smtpheads = None
		return retnull

	if gw.envelope == '' and gw.sender != '':
		gw.smtpheads['Resent-From:'] = gw.sender + '\n'
		gw.envelope = gw.sender
	elif gw.envelope == -1:
		gw.smtpheads = None
		return retnull

	sys.argv[1:] = arg

	return (test, verbose)


def usage():
	i = pyginfo.pygsinfo()

	print '%s version %s - Copyright 2000 Cosimo Alfarano' % (i.PROGNAME, i.VERSION)
	print i.__doc__
	print 
	print 'usage: %s [-h] [-d] [-T] [-V] [-H smtphost] [-l logfile] [-w whitelist] -t recipient@... -s sender@... [-e envelope@...]' % split(sys.argv[0],'/')[-1]
	print '-t -s	recipient, sender are necessary'
	print '-e	envelope [default: same of sender]'
	print '-T for test mode (not send article via SMTP)'
	print '-V for verbose output'
	print '-d for debug'
	print '-h or -v for this info'
	







"""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
	(test, verbose) = parse_cmdline(n2m)
	if (test, verbose) == (None, None):
		usage()
		sys.exit(0)


	# check if n2m has some file prefercences set on commandline
	if(n2m.wlfile == None):
		wl = os.environ['HOME'] + '/pyg.whitelist'
	else:
		wl = n2m.wlfile
	
	if(n2m.logfile == None):
		log = os.environ['HOME'] + '/pyg.log'
	else:
		log = n2m.logfile

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

	wl = whitelist.whitelist(wl,log)

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


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

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

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

	n2m.mergeheads()	# make unique dict from NNTP and SMTP dicts
	
	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(verbose):
		for line in n2m.headers:
			print line[:-1]
	
	if(owner == 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 test):
			n2m.sendarticle()
	else:
		print 'Error: No Headers!!!'

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