# -*- coding: utf-8 -*-

# Copyright (C) 2013-2018 RhodeCode GmbH
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License, version 3
# (only), as published by the Free Software Foundation.
#
# 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 Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# This program is dual-licensed. If you wish to learn more about the
# RhodeCode Enterprise Edition, including its added features, Support services,
# and proprietary license terms, please see https://rhodecode.com/licenses/

"""
Simple smtp mailer used in RhodeCode
"""

import time
import logging
import socket
from email.utils import formatdate

from rhodecode.lib.rcmail.message import Message
from rhodecode.lib.rcmail.utils import DNS_NAME

log = logging.getLogger(__name__)


class SmtpMailer(object):
    """
    SMTP mailer class

    mailer = SmtpMailer(mail_from, user, passwd, mail_server, smtp_auth
                        mail_port, ssl, tls)
    mailer.send(recipients, subject, body, attachment_files)

    :param recipients might be a list of string or single string
    :param attachment_files is a dict of {filename:location}
        it tries to guess the mimetype and attach the file

    """

    def __init__(self, mail_from, user, passwd, mail_server, smtp_auth=None,
                 mail_port=None, ssl=False, tls=False, debug=False):

        self.mail_from = mail_from
        self.mail_server = mail_server
        self.mail_port = mail_port
        self.user = user
        self.passwd = passwd
        self.ssl = ssl
        self.tls = tls
        self.debug = debug
        self.auth = smtp_auth

    def _get_smptlib(self):
        # patch the output
        import smtplib

        class StderrLogger(object):

            def write(self, message):
                log.debug(message)

        org_stderr = smtplib.stderr
        smtplib.stderr = StderrLogger()
        return smtplib

    def send(self, recipients=None, subject='', body='', html='',
             attachment_files=None):
        recipients = recipients or []
        if isinstance(recipients, basestring):
            recipients = [recipients]
        headers = {
            'Date': formatdate(time.time())
        }
        msg = Message(subject, recipients, body, html, self.mail_from,
                      recipients_separator=", ", extra_headers=headers)
        raw_msg = msg.to_message()

        # patched smtplib without stderr
        smtplib = self._get_smptlib()
        if self.ssl:
            smtp_serv = smtplib.SMTP_SSL(self.mail_server, self.mail_port,
                                         local_hostname=DNS_NAME.get_fqdn())
        else:
            smtp_serv = smtplib.SMTP(self.mail_server, self.mail_port,
                                     local_hostname=DNS_NAME.get_fqdn())

        if self.tls:
            smtp_serv.ehlo()
            smtp_serv.starttls()

        if self.debug:
            smtp_serv.set_debuglevel(1)

        smtp_serv.ehlo()
        if self.auth:
            smtp_serv.esmtp_features["auth"] = self.auth

        # if server requires authorization you must provide login and password
        # but only if we have them
        if self.user and self.passwd:
            smtp_serv.login(self.user, self.passwd)

        smtp_serv.sendmail(msg.sender, msg.send_to, raw_msg.as_string())
        log.info('email sent to: %s', recipients)

        try:
            smtp_serv.quit()
        except socket.sslerror:
            # sslerror is raised in tls connections on closing sometimes
            smtp_serv.close()