# Copyright 2018  Lars Wirzenius
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero 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 Affero 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/>.


import email.message
import smtplib


body_tmpl = """\
This is a build notification from ick.

Controller: {controller_url}
Project:    {project}
Build ID:   {build_id}
Log ID:     {log}
Worker:     {worker}
Exit code:  {exit_code}

Build log is attached.

"""


class Sendmail:

    config_fields = [
        'from_addr',
        'controller_url',
        'smtp_server',
        'smtp_port',
        'smtp_user',
        'smtp_password',
    ]

    def __init__(self):
        self._config = None

    def set_config(self, config):
        for field in self.config_fields:
            assert field in config
        self._config = config

    def send(self, recipients, build, log):
        msg = self.construct_msg(recipients, build, log)
        self._send_msg(recipients, msg)

    def _send_msg(self, recipients, msg):
        server = smtplib.SMTP()
        server.connect(
            host=self._config['smtp_server'], port=self._config['smtp_port'])
        server.ehlo()
        server.starttls()
        server.login(self._config['smtp_user'], self._config['smtp_password'])
        server.sendmail(self._config['from_addr'], recipients, msg.as_bytes())

    def construct_msg(self, recipients, build, log):
        msg = email.message.Message()
        msg.add_header('From', self._config['from_addr'])
        msg.add_header('To', ', '.join(recipients))
        msg.add_header('Subject', self.get_subject(build))
        msg.add_header('Content-Type', 'multipart/mixed')
        msg.attach(self.get_body(build))
        msg.attach(self.get_log(log))
        return msg

    def get_subject(self, build):
        return '{status} {build_id}: Ick build notification'.format(**build)

    def get_body(self, build):
        msg = email.message.Message()
        msg.set_payload(body_tmpl.format(
            controller_url=self._config['controller_url'], **build))
        msg.add_header('Content-Type', 'text/plain')
        return msg

    def get_log(self, log):
        msg = email.message.Message()
        msg.set_payload(log.encode('utf-8'))
        msg.add_header('Content-Type', 'text/plain; charset=utf-8')
        msg.add_header(
            'Content-Disposition', 'inline', filename='build.log')
        return msg