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# to you under the Apache License, Version 2.0 (the
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#
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#
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# Mailer module, send mail from a separate thread
import smtplib
import os
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from threading import Thread
from tornado import template

smtpServer = ""
smtpPort = 0
senderAddress = ""
useTLS = False


# Render templates
def render_template(template_name, **kwargs):
    loader = template.Loader(os.path.dirname(os.path.realpath(__file__)) + "/templates")
    t = loader.load(template_name)
    return t.generate(**kwargs)


# Initialize the mailer parameters
def setup(smtpserver, smtpport, senderaddress, usetls):
    global smtpServer, smtpPort, senderAddress, useTLS
    smtpServer = smtpserver
    smtpPort = smtpport
    senderAddress = senderaddress
    useTLS = usetls


# The actual mail sending routine (which should be ran from sendActivationEmail() in a separate thread so that Tornado is not blocked)
def mailerThread(recipientAddress, subject, deviceName, replacementText, emailTemplate, user=None, password=None):
    if not smtpServer:
        return
    msg = MIMEMultipart('alternative')
    msg['Subject'] = subject
    msg['From'] = senderAddress
    msg['To'] = recipientAddress

    # Text version (in case the mail client does not like the HTML part).
    mailText = render_template(emailTemplate + '.txt', validationURL=replacementText, activationCodeStr=replacementText)

    # HTML version
    mailHTML = render_template(emailTemplate + '.html', validationURL=replacementText, activationCodeStr=replacementText)

    mailPartText = MIMEText(mailText, 'plain')
    mailPartHTML = MIMEText(mailHTML, 'html')
    msg.attach(mailPartText)
    msg.attach(mailPartHTML)

    sender = smtplib.SMTP(smtpServer, smtpPort)

    if useTLS:
        sender.starttls()
        sender.ehlo()

    if user:
        sender.login(user, password)

    sender.sendmail(senderAddress, recipientAddress, msg.as_string())
    sender.quit()


def sendActivationEmail(recipientAddress, subject, deviceName, validationURL, user=None, password=None):
    thread = Thread(target=mailerThread, args=(recipientAddress, subject, deviceName, validationURL, 'activation_email', user, password))
    thread.start()


def sendEMpinActivationEmail(recipientAddress, subject, deviceName, activationCode, user=None, password=None):
    ac3 = activationCode % 10000
    ac2 = activationCode / 10000 % 10000
    ac1 = activationCode / (10000 * 10000) % 10000
    activationCodeStr = '%04d-%04d-%04d' % (ac1, ac2, ac3)

    thread = Thread(target=mailerThread, args=(recipientAddress, subject, deviceName, activationCodeStr, 'empin_activation_email', user, password))
    thread.start()