# -*- coding: utf-8 -*-
'''
Module for Sending Messages via SMTP

.. versionadded:: 2014.7.0

:depends:   - smtplib python module
:configuration: This module can be used by either passing a jid and password
    directly to send_message, or by specifying the name of a configuration
    profile in the minion config, minion pillar, or master config.

    For example:

    .. code-block:: yaml

        my-smtp-login:
            smtp.server: smtp.domain.com
            smtp.tls: True
            smtp.sender: admin@domain.com
            smtp.username: myuser
            smtp.password: verybadpass

    The resourcename refers to the resource that is using this account. It is
    user-definable, and optional. The following configurations are both valid:

    .. code-block:: yaml

        my-smtp-login:
            smtp.server: smtp.domain.com
            smtp.tls: True
            smtp.sender: admin@domain.com
            smtp.username: myuser
            smtp.password: verybadpass

        another-smtp-login:
            smtp.server: smtp.domain.com
            smtp.tls: True
            smtp.sender: admin@domain.com
            smtp.username: myuser
            smtp.password: verybadpass

'''

from __future__ import absolute_import, unicode_literals, print_function
import logging
import os
import socket

# Import salt libs
import salt.utils.files

log = logging.getLogger(__name__)

HAS_LIBS = False
try:
    import smtplib
    import email.mime.text
    import email.mime.application
    import email.mime.multipart
    HAS_LIBS = True
except ImportError:
    pass


__virtualname__ = 'smtp'


def __virtual__():
    '''
    Only load this module if smtplib is available on this minion.
    '''
    if HAS_LIBS:
        return __virtualname__
    return (False, 'This module is only loaded if smtplib is available')


def send_msg(recipient,
             message,
             subject='Message from Salt',
             sender=None,
             server=None,
             use_ssl='True',
             username=None,
             password=None,
             profile=None,
             attachments=None):
    '''
    Send a message to an SMTP recipient. Designed for use in states.

    CLI Examples:

    .. code-block:: bash

        salt '*' smtp.send_msg 'admin@example.com' 'This is a salt module test' profile='my-smtp-account'
        salt '*' smtp.send_msg 'admin@example.com' 'This is a salt module test' username='myuser' password='verybadpass' sender='admin@example.com' server='smtp.domain.com'
        salt '*' smtp.send_msg 'admin@example.com' 'This is a salt module test' username='myuser' password='verybadpass' sender='admin@example.com' server='smtp.domain.com' attachments="['/var/log/messages']"
    '''
    if profile:
        creds = __salt__['config.option'](profile)
        server = creds.get('smtp.server')
        use_ssl = creds.get('smtp.tls')
        sender = creds.get('smtp.sender')
        username = creds.get('smtp.username')
        password = creds.get('smtp.password')

    if attachments:
        msg = email.mime.multipart.MIMEMultipart()
        msg.attach(email.mime.text.MIMEText(message))
    else:
        msg = email.mime.text.MIMEText(message)
    msg['Subject'] = subject
    msg['From'] = sender
    msg['To'] = recipient
    recipients = [r.strip() for r in recipient.split(',')]

    try:
        if use_ssl in ['True', 'true']:
            smtpconn = smtplib.SMTP_SSL(server)
        else:
            smtpconn = smtplib.SMTP(server)

    except socket.gaierror as _error:
        log.debug("Exception: %s", _error)
        return False

    if use_ssl not in ('True', 'true'):
        smtpconn.ehlo()
        if smtpconn.has_extn('STARTTLS'):
            try:
                smtpconn.starttls()
            except smtplib.SMTPHeloError:
                log.debug("The server didn’t reply properly \
                        to the HELO greeting.")
                return False
            except smtplib.SMTPException:
                log.debug("The server does not support the STARTTLS extension.")
                return False
            except RuntimeError:
                log.debug("SSL/TLS support is not available \
                        to your Python interpreter.")
                return False
            smtpconn.ehlo()

    if username and password:
        try:
            smtpconn.login(username, password)
        except smtplib.SMTPAuthenticationError as _error:
            log.debug("SMTP Authentication Failure")
            return False

    if attachments:
        for f in attachments:
            name = os.path.basename(f)
            with salt.utils.files.fopen(f, 'rb') as fin:
                att = email.mime.application.MIMEApplication(fin.read(), Name=name)
            att['Content-Disposition'] = 'attachment; filename="{0}"'.format(name)
            msg.attach(att)

    try:
        smtpconn.sendmail(sender, recipients, msg.as_string())
    except smtplib.SMTPRecipientsRefused:
        log.debug("All recipients were refused.")
        return False
    except smtplib.SMTPHeloError:
        log.debug("The server didn’t reply properly to the HELO greeting.")
        return False
    except smtplib.SMTPSenderRefused:
        log.debug("The server didn’t accept the %s.", sender)
        return False
    except smtplib.SMTPDataError:
        log.debug("The server replied with an unexpected error code.")
        return False

    smtpconn.quit()
    return True