# -*- coding: UTF-8 -*-
#
# Copyright (C) 2007 by Jan Dittberner.
#
# 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 3 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.
#
# Version: $Id$

import smtplib
from email.MIMEText import MIMEText
from pyme import core
from pyme.constants.sig import mode

from gnuviechadmin.backend.settings import config

def send_mail(subject, text):
    """This method sends a mail with the given text and subject
    and signs it usign GnuPG. If a public key of the recipient is
    available the mail is encrypted."""
    plain = core.Data(text)
    cipher = core.Data()
    c = core.Context()
    c.set_armor(1)
    signer = config.get('common', 'mailfrom')
    rcpt = config.get('common', 'mailto')
    c.signers_clear()
    for sigkey in [x for x in c.op_keylist_all(signer, 1)]:
      if sigkey.can_sign:
        c.signers_add(sigkey)
      if not c.signers_enum(0):
        raise Exception("No secret keys for signing available for %s." % (
          signer))
    keylist = []
    for key in c.op_keylist_all(rcpt, 0):
      valid = 0
      subkey = key.subkeys
      while subkey:
        keyid = subkey.keyid
        if keyid == None:
          break
        can_encrypt = subkey.can_encrypt
        valid += can_encrypt
        subkey = subkey.next
      if valid:
        keylist.append(key)
    if keylist:
      c.op_encrypt_sign(keylist, 1, plain, cipher)
    else:
      c.op_sign(plain, cipher, mode.CLEAR)
    cipher.seek(0,0)

    msg = MIMEText(cipher.read())
    if keylist:
      msg.set_param("x-action", "pgp-encrypted")
    msg['Subject'] = subject
    msg['From'] = signer
    msg['To'] = rcpt

    s = smtplib.SMTP()
    s.connect()
    s.sendmail(signer, [rcpt], msg.as_string())
    s.close()