diff --git a/src/lib/PHPMailer/DSNConfigurator.php b/src/lib/PHPMailer/DSNConfigurator.php
new file mode 100644
index 0000000..566c961
--- /dev/null
+++ b/src/lib/PHPMailer/DSNConfigurator.php
@@ -0,0 +1,245 @@
+<?php
+
+/**
+ * PHPMailer - PHP email creation and transport class.
+ * PHP Version 5.5.
+ *
+ * @see https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2023 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * Configure PHPMailer with DSN string.
+ *
+ * @see https://en.wikipedia.org/wiki/Data_source_name
+ *
+ * @author Oleg Voronkovich <oleg-voronkovich@yandex.ru>
+ */
+class DSNConfigurator
+{
+    /**
+     * Create new PHPMailer instance configured by DSN.
+     *
+     * @param string $dsn        DSN
+     * @param bool   $exceptions Should we throw external exceptions?
+     *
+     * @return PHPMailer
+     */
+    public static function mailer($dsn, $exceptions = null)
+    {
+        static $configurator = null;
+
+        if (null === $configurator) {
+            $configurator = new DSNConfigurator();
+        }
+
+        return $configurator->configure(new PHPMailer($exceptions), $dsn);
+    }
+
+    /**
+     * Configure PHPMailer instance with DSN string.
+     *
+     * @param PHPMailer $mailer PHPMailer instance
+     * @param string    $dsn    DSN
+     *
+     * @return PHPMailer
+     */
+    public function configure(PHPMailer $mailer, $dsn)
+    {
+        $config = $this->parseDSN($dsn);
+
+        $this->applyConfig($mailer, $config);
+
+        return $mailer;
+    }
+
+    /**
+     * Parse DSN string.
+     *
+     * @param string $dsn DSN
+     *
+     * @throws Exception If DSN is malformed
+     *
+     * @return array Configuration
+     */
+    private function parseDSN($dsn)
+    {
+        $config = $this->parseUrl($dsn);
+
+        if (false === $config || !isset($config['scheme']) || !isset($config['host'])) {
+            throw new Exception('Malformed DSN');
+        }
+
+        if (isset($config['query'])) {
+            parse_str($config['query'], $config['query']);
+        }
+
+        return $config;
+    }
+
+    /**
+     * Apply configuration to mailer.
+     *
+     * @param PHPMailer $mailer PHPMailer instance
+     * @param array     $config Configuration
+     *
+     * @throws Exception If scheme is invalid
+     */
+    private function applyConfig(PHPMailer $mailer, $config)
+    {
+        switch ($config['scheme']) {
+            case 'mail':
+                $mailer->isMail();
+                break;
+            case 'sendmail':
+                $mailer->isSendmail();
+                break;
+            case 'qmail':
+                $mailer->isQmail();
+                break;
+            case 'smtp':
+            case 'smtps':
+                $mailer->isSMTP();
+                $this->configureSMTP($mailer, $config);
+                break;
+            default:
+                throw new Exception(
+                    sprintf(
+                        'Invalid scheme: "%s". Allowed values: "mail", "sendmail", "qmail", "smtp", "smtps".',
+                        $config['scheme']
+                    )
+                );
+        }
+
+        if (isset($config['query'])) {
+            $this->configureOptions($mailer, $config['query']);
+        }
+    }
+
+    /**
+     * Configure SMTP.
+     *
+     * @param PHPMailer $mailer PHPMailer instance
+     * @param array     $config Configuration
+     */
+    private function configureSMTP($mailer, $config)
+    {
+        $isSMTPS = 'smtps' === $config['scheme'];
+
+        if ($isSMTPS) {
+            $mailer->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
+        }
+
+        $mailer->Host = $config['host'];
+
+        if (isset($config['port'])) {
+            $mailer->Port = $config['port'];
+        } elseif ($isSMTPS) {
+            $mailer->Port = SMTP::DEFAULT_SECURE_PORT;
+        }
+
+        $mailer->SMTPAuth = isset($config['user']) || isset($config['pass']);
+
+        if (isset($config['user'])) {
+            $mailer->Username = $config['user'];
+        }
+
+        if (isset($config['pass'])) {
+            $mailer->Password = $config['pass'];
+        }
+    }
+
+    /**
+     * Configure options.
+     *
+     * @param PHPMailer $mailer  PHPMailer instance
+     * @param array     $options Options
+     *
+     * @throws Exception If option is unknown
+     */
+    private function configureOptions(PHPMailer $mailer, $options)
+    {
+        $allowedOptions = get_object_vars($mailer);
+
+        unset($allowedOptions['Mailer']);
+        unset($allowedOptions['SMTPAuth']);
+        unset($allowedOptions['Username']);
+        unset($allowedOptions['Password']);
+        unset($allowedOptions['Hostname']);
+        unset($allowedOptions['Port']);
+        unset($allowedOptions['ErrorInfo']);
+
+        $allowedOptions = \array_keys($allowedOptions);
+
+        foreach ($options as $key => $value) {
+            if (!in_array($key, $allowedOptions)) {
+                throw new Exception(
+                    sprintf(
+                        'Unknown option: "%s". Allowed values: "%s"',
+                        $key,
+                        implode('", "', $allowedOptions)
+                    )
+                );
+            }
+
+            switch ($key) {
+                case 'AllowEmpty':
+                case 'SMTPAutoTLS':
+                case 'SMTPKeepAlive':
+                case 'SingleTo':
+                case 'UseSendmailOptions':
+                case 'do_verp':
+                case 'DKIM_copyHeaderFields':
+                    $mailer->$key = (bool) $value;
+                    break;
+                case 'Priority':
+                case 'SMTPDebug':
+                case 'WordWrap':
+                    $mailer->$key = (int) $value;
+                    break;
+                default:
+                    $mailer->$key = $value;
+                    break;
+            }
+        }
+    }
+
+    /**
+     * Parse a URL.
+     * Wrapper for the built-in parse_url function to work around a bug in PHP 5.5.
+     *
+     * @param string $url URL
+     *
+     * @return array|false
+     */
+    protected function parseUrl($url)
+    {
+        if (\PHP_VERSION_ID >= 50600 || false === strpos($url, '?')) {
+            return parse_url($url);
+        }
+
+        $chunks = explode('?', $url);
+        if (is_array($chunks)) {
+            $result = parse_url($chunks[0]);
+            if (is_array($result)) {
+                $result['query'] = $chunks[1];
+            }
+            return $result;
+        }
+
+        return false;
+    }
+}
diff --git a/src/lib/PHPMailer/Exception.php b/src/lib/PHPMailer/Exception.php
new file mode 100644
index 0000000..52eaf95
--- /dev/null
+++ b/src/lib/PHPMailer/Exception.php
@@ -0,0 +1,40 @@
+<?php
+
+/**
+ * PHPMailer Exception class.
+ * PHP Version 5.5.
+ *
+ * @see       https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * PHPMailer exception handler.
+ *
+ * @author Marcus Bointon <phpmailer@synchromedia.co.uk>
+ */
+class Exception extends \Exception
+{
+    /**
+     * Prettify error message output.
+     *
+     * @return string
+     */
+    public function errorMessage()
+    {
+        return '<strong>' . htmlspecialchars($this->getMessage(), ENT_COMPAT | ENT_HTML401) . "</strong><br />\n";
+    }
+}
diff --git a/src/lib/PHPMailer/LICENSE b/src/lib/PHPMailer/LICENSE
new file mode 100644
index 0000000..f166cc5
--- /dev/null
+++ b/src/lib/PHPMailer/LICENSE
@@ -0,0 +1,502 @@
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+ 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
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+
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+specially designated software packages--typically libraries--of the
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+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations below.
+
+  When we speak of free software, we are referring to freedom of use,
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+
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+all its terms and conditions for copying, distributing or modifying
+the Library or works based on it.
+
+  10. Each time you redistribute the Library (or any work based on the
+Library), the recipient automatically receives a license from the
+original licensor to copy, distribute, link with or modify the Library
+subject to these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties with
+this License.
+
+  11. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot
+distribute so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you
+may not distribute the Library at all.  For example, if a patent
+license would not permit royalty-free redistribution of the Library by
+all those who receive copies directly or indirectly through you, then
+the only way you could satisfy both it and this License would be to
+refrain entirely from distribution of the Library.
+
+If any portion of this section is held invalid or unenforceable under any
+particular circumstance, the balance of the section is intended to apply,
+and the section as a whole is intended to apply in other circumstances.
+
+It is not the purpose of this section to induce you to infringe any
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+integrity of the free software distribution system which is
+implemented by public license practices.  Many people have made
+generous contributions to the wide range of software distributed
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+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  12. If the distribution and/or use of the Library is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Library under this License may add
+an explicit geographical distribution limitation excluding those countries,
+so that distribution is permitted only in or among countries not thus
+excluded.  In such case, this License incorporates the limitation as if
+written in the body of this License.
+
+  13. The Free Software Foundation may publish revised and/or new
+versions of the Lesser General Public License from time to time.
+Such new versions will be similar in spirit to the present version,
+but may differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Library
+specifies a version number of this License which applies to it and
+"any later version", you have the option of following the terms and
+conditions either of that version or of any later version published by
+the Free Software Foundation.  If the Library does not specify a
+license version number, you may choose any version ever published by
+the Free Software Foundation.
+
+  14. If you wish to incorporate parts of the Library into other free
+programs whose distribution conditions are incompatible with these,
+write to the author to ask for permission.  For software which is
+copyrighted by the Free Software Foundation, write to the Free
+Software Foundation; we sometimes make exceptions for this.  Our
+decision will be guided by the two goals of preserving the free status
+of all derivatives of our free software and of promoting the sharing
+and reuse of software generally.
+
+                            NO WARRANTY
+
+  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
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+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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+  16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
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+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+           How to Apply These Terms to Your New Libraries
+
+  If you develop a new library, and you want it to be of the greatest
+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms of the
+ordinary General Public License).
+
+  To apply these terms, attach the following notices to the library.  It is
+safest to attach them to the start of each source file to most effectively
+convey the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the library's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library 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
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the library, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
\ No newline at end of file
diff --git a/src/lib/PHPMailer/OAuth.php b/src/lib/PHPMailer/OAuth.php
new file mode 100644
index 0000000..c1d5b77
--- /dev/null
+++ b/src/lib/PHPMailer/OAuth.php
@@ -0,0 +1,139 @@
+<?php
+
+/**
+ * PHPMailer - PHP email creation and transport class.
+ * PHP Version 5.5.
+ *
+ * @see       https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+use League\OAuth2\Client\Grant\RefreshToken;
+use League\OAuth2\Client\Provider\AbstractProvider;
+use League\OAuth2\Client\Token\AccessToken;
+
+/**
+ * OAuth - OAuth2 authentication wrapper class.
+ * Uses the oauth2-client package from the League of Extraordinary Packages.
+ *
+ * @see     http://oauth2-client.thephpleague.com
+ *
+ * @author  Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ */
+class OAuth implements OAuthTokenProvider
+{
+    /**
+     * An instance of the League OAuth Client Provider.
+     *
+     * @var AbstractProvider
+     */
+    protected $provider;
+
+    /**
+     * The current OAuth access token.
+     *
+     * @var AccessToken
+     */
+    protected $oauthToken;
+
+    /**
+     * The user's email address, usually used as the login ID
+     * and also the from address when sending email.
+     *
+     * @var string
+     */
+    protected $oauthUserEmail = '';
+
+    /**
+     * The client secret, generated in the app definition of the service you're connecting to.
+     *
+     * @var string
+     */
+    protected $oauthClientSecret = '';
+
+    /**
+     * The client ID, generated in the app definition of the service you're connecting to.
+     *
+     * @var string
+     */
+    protected $oauthClientId = '';
+
+    /**
+     * The refresh token, used to obtain new AccessTokens.
+     *
+     * @var string
+     */
+    protected $oauthRefreshToken = '';
+
+    /**
+     * OAuth constructor.
+     *
+     * @param array $options Associative array containing
+     *                       `provider`, `userName`, `clientSecret`, `clientId` and `refreshToken` elements
+     */
+    public function __construct($options)
+    {
+        $this->provider = $options['provider'];
+        $this->oauthUserEmail = $options['userName'];
+        $this->oauthClientSecret = $options['clientSecret'];
+        $this->oauthClientId = $options['clientId'];
+        $this->oauthRefreshToken = $options['refreshToken'];
+    }
+
+    /**
+     * Get a new RefreshToken.
+     *
+     * @return RefreshToken
+     */
+    protected function getGrant()
+    {
+        return new RefreshToken();
+    }
+
+    /**
+     * Get a new AccessToken.
+     *
+     * @return AccessToken
+     */
+    protected function getToken()
+    {
+        return $this->provider->getAccessToken(
+            $this->getGrant(),
+            ['refresh_token' => $this->oauthRefreshToken]
+        );
+    }
+
+    /**
+     * Generate a base64-encoded OAuth token.
+     *
+     * @return string
+     */
+    public function getOauth64()
+    {
+        //Get a new token if it's not available or has expired
+        if (null === $this->oauthToken || $this->oauthToken->hasExpired()) {
+            $this->oauthToken = $this->getToken();
+        }
+
+        return base64_encode(
+            'user=' .
+            $this->oauthUserEmail .
+            "\001auth=Bearer " .
+            $this->oauthToken .
+            "\001\001"
+        );
+    }
+}
diff --git a/src/lib/PHPMailer/OAuthTokenProvider.php b/src/lib/PHPMailer/OAuthTokenProvider.php
new file mode 100644
index 0000000..1155507
--- /dev/null
+++ b/src/lib/PHPMailer/OAuthTokenProvider.php
@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * PHPMailer - PHP email creation and transport class.
+ * PHP Version 5.5.
+ *
+ * @see https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * OAuthTokenProvider - OAuth2 token provider interface.
+ * Provides base64 encoded OAuth2 auth strings for SMTP authentication.
+ *
+ * @see     OAuth
+ * @see     SMTP::authenticate()
+ *
+ * @author  Peter Scopes (pdscopes)
+ * @author  Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ */
+interface OAuthTokenProvider
+{
+    /**
+     * Generate a base64-encoded OAuth token ensuring that the access token has not expired.
+     * The string to be base 64 encoded should be in the form:
+     * "user=<user_email_address>\001auth=Bearer <access_token>\001\001"
+     *
+     * @return string
+     */
+    public function getOauth64();
+}
diff --git a/src/lib/PHPMailer/PHPMailer.php b/src/lib/PHPMailer/PHPMailer.php
new file mode 100644
index 0000000..7f56ea2
--- /dev/null
+++ b/src/lib/PHPMailer/PHPMailer.php
@@ -0,0 +1,5126 @@
+<?php
+
+/**
+ * PHPMailer - PHP email creation and transport class.
+ * PHP Version 5.5.
+ *
+ * @see https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * PHPMailer - PHP email creation and transport class.
+ *
+ * @author Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author Brent R. Matzelle (original founder)
+ */
+class PHPMailer
+{
+    const CHARSET_ASCII = 'us-ascii';
+    const CHARSET_ISO88591 = 'iso-8859-1';
+    const CHARSET_UTF8 = 'utf-8';
+
+    const CONTENT_TYPE_PLAINTEXT = 'text/plain';
+    const CONTENT_TYPE_TEXT_CALENDAR = 'text/calendar';
+    const CONTENT_TYPE_TEXT_HTML = 'text/html';
+    const CONTENT_TYPE_MULTIPART_ALTERNATIVE = 'multipart/alternative';
+    const CONTENT_TYPE_MULTIPART_MIXED = 'multipart/mixed';
+    const CONTENT_TYPE_MULTIPART_RELATED = 'multipart/related';
+
+    const ENCODING_7BIT = '7bit';
+    const ENCODING_8BIT = '8bit';
+    const ENCODING_BASE64 = 'base64';
+    const ENCODING_BINARY = 'binary';
+    const ENCODING_QUOTED_PRINTABLE = 'quoted-printable';
+
+    const ENCRYPTION_STARTTLS = 'tls';
+    const ENCRYPTION_SMTPS = 'ssl';
+
+    const ICAL_METHOD_REQUEST = 'REQUEST';
+    const ICAL_METHOD_PUBLISH = 'PUBLISH';
+    const ICAL_METHOD_REPLY = 'REPLY';
+    const ICAL_METHOD_ADD = 'ADD';
+    const ICAL_METHOD_CANCEL = 'CANCEL';
+    const ICAL_METHOD_REFRESH = 'REFRESH';
+    const ICAL_METHOD_COUNTER = 'COUNTER';
+    const ICAL_METHOD_DECLINECOUNTER = 'DECLINECOUNTER';
+
+    /**
+     * Email priority.
+     * Options: null (default), 1 = High, 3 = Normal, 5 = low.
+     * When null, the header is not set at all.
+     *
+     * @var int|null
+     */
+    public $Priority;
+
+    /**
+     * The character set of the message.
+     *
+     * @var string
+     */
+    public $CharSet = self::CHARSET_ISO88591;
+
+    /**
+     * The MIME Content-type of the message.
+     *
+     * @var string
+     */
+    public $ContentType = self::CONTENT_TYPE_PLAINTEXT;
+
+    /**
+     * The message encoding.
+     * Options: "8bit", "7bit", "binary", "base64", and "quoted-printable".
+     *
+     * @var string
+     */
+    public $Encoding = self::ENCODING_8BIT;
+
+    /**
+     * Holds the most recent mailer error message.
+     *
+     * @var string
+     */
+    public $ErrorInfo = '';
+
+    /**
+     * The From email address for the message.
+     *
+     * @var string
+     */
+    public $From = '';
+
+    /**
+     * The From name of the message.
+     *
+     * @var string
+     */
+    public $FromName = '';
+
+    /**
+     * The envelope sender of the message.
+     * This will usually be turned into a Return-Path header by the receiver,
+     * and is the address that bounces will be sent to.
+     * If not empty, will be passed via `-f` to sendmail or as the 'MAIL FROM' value over SMTP.
+     *
+     * @var string
+     */
+    public $Sender = '';
+
+    /**
+     * The Subject of the message.
+     *
+     * @var string
+     */
+    public $Subject = '';
+
+    /**
+     * An HTML or plain text message body.
+     * If HTML then call isHTML(true).
+     *
+     * @var string
+     */
+    public $Body = '';
+
+    /**
+     * The plain-text message body.
+     * This body can be read by mail clients that do not have HTML email
+     * capability such as mutt & Eudora.
+     * Clients that can read HTML will view the normal Body.
+     *
+     * @var string
+     */
+    public $AltBody = '';
+
+    /**
+     * An iCal message part body.
+     * Only supported in simple alt or alt_inline message types
+     * To generate iCal event structures, use classes like EasyPeasyICS or iCalcreator.
+     *
+     * @see http://sprain.ch/blog/downloads/php-class-easypeasyics-create-ical-files-with-php/
+     * @see http://kigkonsult.se/iCalcreator/
+     *
+     * @var string
+     */
+    public $Ical = '';
+
+    /**
+     * Value-array of "method" in Contenttype header "text/calendar"
+     *
+     * @var string[]
+     */
+    protected static $IcalMethods = [
+        self::ICAL_METHOD_REQUEST,
+        self::ICAL_METHOD_PUBLISH,
+        self::ICAL_METHOD_REPLY,
+        self::ICAL_METHOD_ADD,
+        self::ICAL_METHOD_CANCEL,
+        self::ICAL_METHOD_REFRESH,
+        self::ICAL_METHOD_COUNTER,
+        self::ICAL_METHOD_DECLINECOUNTER,
+    ];
+
+    /**
+     * The complete compiled MIME message body.
+     *
+     * @var string
+     */
+    protected $MIMEBody = '';
+
+    /**
+     * The complete compiled MIME message headers.
+     *
+     * @var string
+     */
+    protected $MIMEHeader = '';
+
+    /**
+     * Extra headers that createHeader() doesn't fold in.
+     *
+     * @var string
+     */
+    protected $mailHeader = '';
+
+    /**
+     * Word-wrap the message body to this number of chars.
+     * Set to 0 to not wrap. A useful value here is 78, for RFC2822 section 2.1.1 compliance.
+     *
+     * @see static::STD_LINE_LENGTH
+     *
+     * @var int
+     */
+    public $WordWrap = 0;
+
+    /**
+     * Which method to use to send mail.
+     * Options: "mail", "sendmail", or "smtp".
+     *
+     * @var string
+     */
+    public $Mailer = 'mail';
+
+    /**
+     * The path to the sendmail program.
+     *
+     * @var string
+     */
+    public $Sendmail = '/usr/sbin/sendmail';
+
+    /**
+     * Whether mail() uses a fully sendmail-compatible MTA.
+     * One which supports sendmail's "-oi -f" options.
+     *
+     * @var bool
+     */
+    public $UseSendmailOptions = true;
+
+    /**
+     * The email address that a reading confirmation should be sent to, also known as read receipt.
+     *
+     * @var string
+     */
+    public $ConfirmReadingTo = '';
+
+    /**
+     * The hostname to use in the Message-ID header and as default HELO string.
+     * If empty, PHPMailer attempts to find one with, in order,
+     * $_SERVER['SERVER_NAME'], gethostname(), php_uname('n'), or the value
+     * 'localhost.localdomain'.
+     *
+     * @see PHPMailer::$Helo
+     *
+     * @var string
+     */
+    public $Hostname = '';
+
+    /**
+     * An ID to be used in the Message-ID header.
+     * If empty, a unique id will be generated.
+     * You can set your own, but it must be in the format "<id@domain>",
+     * as defined in RFC5322 section 3.6.4 or it will be ignored.
+     *
+     * @see https://tools.ietf.org/html/rfc5322#section-3.6.4
+     *
+     * @var string
+     */
+    public $MessageID = '';
+
+    /**
+     * The message Date to be used in the Date header.
+     * If empty, the current date will be added.
+     *
+     * @var string
+     */
+    public $MessageDate = '';
+
+    /**
+     * SMTP hosts.
+     * Either a single hostname or multiple semicolon-delimited hostnames.
+     * You can also specify a different port
+     * for each host by using this format: [hostname:port]
+     * (e.g. "smtp1.example.com:25;smtp2.example.com").
+     * You can also specify encryption type, for example:
+     * (e.g. "tls://smtp1.example.com:587;ssl://smtp2.example.com:465").
+     * Hosts will be tried in order.
+     *
+     * @var string
+     */
+    public $Host = 'localhost';
+
+    /**
+     * The default SMTP server port.
+     *
+     * @var int
+     */
+    public $Port = 25;
+
+    /**
+     * The SMTP HELO/EHLO name used for the SMTP connection.
+     * Default is $Hostname. If $Hostname is empty, PHPMailer attempts to find
+     * one with the same method described above for $Hostname.
+     *
+     * @see PHPMailer::$Hostname
+     *
+     * @var string
+     */
+    public $Helo = '';
+
+    /**
+     * What kind of encryption to use on the SMTP connection.
+     * Options: '', static::ENCRYPTION_STARTTLS, or static::ENCRYPTION_SMTPS.
+     *
+     * @var string
+     */
+    public $SMTPSecure = '';
+
+    /**
+     * Whether to enable TLS encryption automatically if a server supports it,
+     * even if `SMTPSecure` is not set to 'tls'.
+     * Be aware that in PHP >= 5.6 this requires that the server's certificates are valid.
+     *
+     * @var bool
+     */
+    public $SMTPAutoTLS = true;
+
+    /**
+     * Whether to use SMTP authentication.
+     * Uses the Username and Password properties.
+     *
+     * @see PHPMailer::$Username
+     * @see PHPMailer::$Password
+     *
+     * @var bool
+     */
+    public $SMTPAuth = false;
+
+    /**
+     * Options array passed to stream_context_create when connecting via SMTP.
+     *
+     * @var array
+     */
+    public $SMTPOptions = [];
+
+    /**
+     * SMTP username.
+     *
+     * @var string
+     */
+    public $Username = '';
+
+    /**
+     * SMTP password.
+     *
+     * @var string
+     */
+    public $Password = '';
+
+    /**
+     * SMTP authentication type. Options are CRAM-MD5, LOGIN, PLAIN, XOAUTH2.
+     * If not specified, the first one from that list that the server supports will be selected.
+     *
+     * @var string
+     */
+    public $AuthType = '';
+
+    /**
+     * An implementation of the PHPMailer OAuthTokenProvider interface.
+     *
+     * @var OAuthTokenProvider
+     */
+    protected $oauth;
+
+    /**
+     * The SMTP server timeout in seconds.
+     * Default of 5 minutes (300sec) is from RFC2821 section 4.5.3.2.
+     *
+     * @var int
+     */
+    public $Timeout = 300;
+
+    /**
+     * Comma separated list of DSN notifications
+     * 'NEVER' under no circumstances a DSN must be returned to the sender.
+     *         If you use NEVER all other notifications will be ignored.
+     * 'SUCCESS' will notify you when your mail has arrived at its destination.
+     * 'FAILURE' will arrive if an error occurred during delivery.
+     * 'DELAY'   will notify you if there is an unusual delay in delivery, but the actual
+     *           delivery's outcome (success or failure) is not yet decided.
+     *
+     * @see https://tools.ietf.org/html/rfc3461 See section 4.1 for more information about NOTIFY
+     */
+    public $dsn = '';
+
+    /**
+     * SMTP class debug output mode.
+     * Debug output level.
+     * Options:
+     * @see SMTP::DEBUG_OFF: No output
+     * @see SMTP::DEBUG_CLIENT: Client messages
+     * @see SMTP::DEBUG_SERVER: Client and server messages
+     * @see SMTP::DEBUG_CONNECTION: As SERVER plus connection status
+     * @see SMTP::DEBUG_LOWLEVEL: Noisy, low-level data output, rarely needed
+     *
+     * @see SMTP::$do_debug
+     *
+     * @var int
+     */
+    public $SMTPDebug = 0;
+
+    /**
+     * How to handle debug output.
+     * Options:
+     * * `echo` Output plain-text as-is, appropriate for CLI
+     * * `html` Output escaped, line breaks converted to `<br>`, appropriate for browser output
+     * * `error_log` Output to error log as configured in php.ini
+     * By default PHPMailer will use `echo` if run from a `cli` or `cli-server` SAPI, `html` otherwise.
+     * Alternatively, you can provide a callable expecting two params: a message string and the debug level:
+     *
+     * ```php
+     * $mail->Debugoutput = function($str, $level) {echo "debug level $level; message: $str";};
+     * ```
+     *
+     * Alternatively, you can pass in an instance of a PSR-3 compatible logger, though only `debug`
+     * level output is used:
+     *
+     * ```php
+     * $mail->Debugoutput = new myPsr3Logger;
+     * ```
+     *
+     * @see SMTP::$Debugoutput
+     *
+     * @var string|callable|\Psr\Log\LoggerInterface
+     */
+    public $Debugoutput = 'echo';
+
+    /**
+     * Whether to keep the SMTP connection open after each message.
+     * If this is set to true then the connection will remain open after a send,
+     * and closing the connection will require an explicit call to smtpClose().
+     * It's a good idea to use this if you are sending multiple messages as it reduces overhead.
+     * See the mailing list example for how to use it.
+     *
+     * @var bool
+     */
+    public $SMTPKeepAlive = false;
+
+    /**
+     * Whether to split multiple to addresses into multiple messages
+     * or send them all in one message.
+     * Only supported in `mail` and `sendmail` transports, not in SMTP.
+     *
+     * @var bool
+     *
+     * @deprecated 6.0.0 PHPMailer isn't a mailing list manager!
+     */
+    public $SingleTo = false;
+
+    /**
+     * Storage for addresses when SingleTo is enabled.
+     *
+     * @var array
+     */
+    protected $SingleToArray = [];
+
+    /**
+     * Whether to generate VERP addresses on send.
+     * Only applicable when sending via SMTP.
+     *
+     * @see https://en.wikipedia.org/wiki/Variable_envelope_return_path
+     * @see http://www.postfix.org/VERP_README.html Postfix VERP info
+     *
+     * @var bool
+     */
+    public $do_verp = false;
+
+    /**
+     * Whether to allow sending messages with an empty body.
+     *
+     * @var bool
+     */
+    public $AllowEmpty = false;
+
+    /**
+     * DKIM selector.
+     *
+     * @var string
+     */
+    public $DKIM_selector = '';
+
+    /**
+     * DKIM Identity.
+     * Usually the email address used as the source of the email.
+     *
+     * @var string
+     */
+    public $DKIM_identity = '';
+
+    /**
+     * DKIM passphrase.
+     * Used if your key is encrypted.
+     *
+     * @var string
+     */
+    public $DKIM_passphrase = '';
+
+    /**
+     * DKIM signing domain name.
+     *
+     * @example 'example.com'
+     *
+     * @var string
+     */
+    public $DKIM_domain = '';
+
+    /**
+     * DKIM Copy header field values for diagnostic use.
+     *
+     * @var bool
+     */
+    public $DKIM_copyHeaderFields = true;
+
+    /**
+     * DKIM Extra signing headers.
+     *
+     * @example ['List-Unsubscribe', 'List-Help']
+     *
+     * @var array
+     */
+    public $DKIM_extraHeaders = [];
+
+    /**
+     * DKIM private key file path.
+     *
+     * @var string
+     */
+    public $DKIM_private = '';
+
+    /**
+     * DKIM private key string.
+     *
+     * If set, takes precedence over `$DKIM_private`.
+     *
+     * @var string
+     */
+    public $DKIM_private_string = '';
+
+    /**
+     * Callback Action function name.
+     *
+     * The function that handles the result of the send email action.
+     * It is called out by send() for each email sent.
+     *
+     * Value can be any php callable: http://www.php.net/is_callable
+     *
+     * Parameters:
+     *   bool $result        result of the send action
+     *   array   $to            email addresses of the recipients
+     *   array   $cc            cc email addresses
+     *   array   $bcc           bcc email addresses
+     *   string  $subject       the subject
+     *   string  $body          the email body
+     *   string  $from          email address of sender
+     *   string  $extra         extra information of possible use
+     *                          "smtp_transaction_id' => last smtp transaction id
+     *
+     * @var string
+     */
+    public $action_function = '';
+
+    /**
+     * What to put in the X-Mailer header.
+     * Options: An empty string for PHPMailer default, whitespace/null for none, or a string to use.
+     *
+     * @var string|null
+     */
+    public $XMailer = '';
+
+    /**
+     * Which validator to use by default when validating email addresses.
+     * May be a callable to inject your own validator, but there are several built-in validators.
+     * The default validator uses PHP's FILTER_VALIDATE_EMAIL filter_var option.
+     *
+     * @see PHPMailer::validateAddress()
+     *
+     * @var string|callable
+     */
+    public static $validator = 'php';
+
+    /**
+     * An instance of the SMTP sender class.
+     *
+     * @var SMTP
+     */
+    protected $smtp;
+
+    /**
+     * The array of 'to' names and addresses.
+     *
+     * @var array
+     */
+    protected $to = [];
+
+    /**
+     * The array of 'cc' names and addresses.
+     *
+     * @var array
+     */
+    protected $cc = [];
+
+    /**
+     * The array of 'bcc' names and addresses.
+     *
+     * @var array
+     */
+    protected $bcc = [];
+
+    /**
+     * The array of reply-to names and addresses.
+     *
+     * @var array
+     */
+    protected $ReplyTo = [];
+
+    /**
+     * An array of all kinds of addresses.
+     * Includes all of $to, $cc, $bcc.
+     *
+     * @see PHPMailer::$to
+     * @see PHPMailer::$cc
+     * @see PHPMailer::$bcc
+     *
+     * @var array
+     */
+    protected $all_recipients = [];
+
+    /**
+     * An array of names and addresses queued for validation.
+     * In send(), valid and non duplicate entries are moved to $all_recipients
+     * and one of $to, $cc, or $bcc.
+     * This array is used only for addresses with IDN.
+     *
+     * @see PHPMailer::$to
+     * @see PHPMailer::$cc
+     * @see PHPMailer::$bcc
+     * @see PHPMailer::$all_recipients
+     *
+     * @var array
+     */
+    protected $RecipientsQueue = [];
+
+    /**
+     * An array of reply-to names and addresses queued for validation.
+     * In send(), valid and non duplicate entries are moved to $ReplyTo.
+     * This array is used only for addresses with IDN.
+     *
+     * @see PHPMailer::$ReplyTo
+     *
+     * @var array
+     */
+    protected $ReplyToQueue = [];
+
+    /**
+     * The array of attachments.
+     *
+     * @var array
+     */
+    protected $attachment = [];
+
+    /**
+     * The array of custom headers.
+     *
+     * @var array
+     */
+    protected $CustomHeader = [];
+
+    /**
+     * The most recent Message-ID (including angular brackets).
+     *
+     * @var string
+     */
+    protected $lastMessageID = '';
+
+    /**
+     * The message's MIME type.
+     *
+     * @var string
+     */
+    protected $message_type = '';
+
+    /**
+     * The array of MIME boundary strings.
+     *
+     * @var array
+     */
+    protected $boundary = [];
+
+    /**
+     * The array of available text strings for the current language.
+     *
+     * @var array
+     */
+    protected $language = [];
+
+    /**
+     * The number of errors encountered.
+     *
+     * @var int
+     */
+    protected $error_count = 0;
+
+    /**
+     * The S/MIME certificate file path.
+     *
+     * @var string
+     */
+    protected $sign_cert_file = '';
+
+    /**
+     * The S/MIME key file path.
+     *
+     * @var string
+     */
+    protected $sign_key_file = '';
+
+    /**
+     * The optional S/MIME extra certificates ("CA Chain") file path.
+     *
+     * @var string
+     */
+    protected $sign_extracerts_file = '';
+
+    /**
+     * The S/MIME password for the key.
+     * Used only if the key is encrypted.
+     *
+     * @var string
+     */
+    protected $sign_key_pass = '';
+
+    /**
+     * Whether to throw exceptions for errors.
+     *
+     * @var bool
+     */
+    protected $exceptions = false;
+
+    /**
+     * Unique ID used for message ID and boundaries.
+     *
+     * @var string
+     */
+    protected $uniqueid = '';
+
+    /**
+     * The PHPMailer Version number.
+     *
+     * @var string
+     */
+    const VERSION = '6.8.1';
+
+    /**
+     * Error severity: message only, continue processing.
+     *
+     * @var int
+     */
+    const STOP_MESSAGE = 0;
+
+    /**
+     * Error severity: message, likely ok to continue processing.
+     *
+     * @var int
+     */
+    const STOP_CONTINUE = 1;
+
+    /**
+     * Error severity: message, plus full stop, critical error reached.
+     *
+     * @var int
+     */
+    const STOP_CRITICAL = 2;
+
+    /**
+     * The SMTP standard CRLF line break.
+     * If you want to change line break format, change static::$LE, not this.
+     */
+    const CRLF = "\r\n";
+
+    /**
+     * "Folding White Space" a white space string used for line folding.
+     */
+    const FWS = ' ';
+
+    /**
+     * SMTP RFC standard line ending; Carriage Return, Line Feed.
+     *
+     * @var string
+     */
+    protected static $LE = self::CRLF;
+
+    /**
+     * The maximum line length supported by mail().
+     *
+     * Background: mail() will sometimes corrupt messages
+     * with headers longer than 65 chars, see #818.
+     *
+     * @var int
+     */
+    const MAIL_MAX_LINE_LENGTH = 63;
+
+    /**
+     * The maximum line length allowed by RFC 2822 section 2.1.1.
+     *
+     * @var int
+     */
+    const MAX_LINE_LENGTH = 998;
+
+    /**
+     * The lower maximum line length allowed by RFC 2822 section 2.1.1.
+     * This length does NOT include the line break
+     * 76 means that lines will be 77 or 78 chars depending on whether
+     * the line break format is LF or CRLF; both are valid.
+     *
+     * @var int
+     */
+    const STD_LINE_LENGTH = 76;
+
+    /**
+     * Constructor.
+     *
+     * @param bool $exceptions Should we throw external exceptions?
+     */
+    public function __construct($exceptions = null)
+    {
+        if (null !== $exceptions) {
+            $this->exceptions = (bool) $exceptions;
+        }
+        //Pick an appropriate debug output format automatically
+        $this->Debugoutput = (strpos(PHP_SAPI, 'cli') !== false ? 'echo' : 'html');
+    }
+
+    /**
+     * Destructor.
+     */
+    public function __destruct()
+    {
+        //Close any open SMTP connection nicely
+        $this->smtpClose();
+    }
+
+    /**
+     * Call mail() in a safe_mode-aware fashion.
+     * Also, unless sendmail_path points to sendmail (or something that
+     * claims to be sendmail), don't pass params (not a perfect fix,
+     * but it will do).
+     *
+     * @param string      $to      To
+     * @param string      $subject Subject
+     * @param string      $body    Message Body
+     * @param string      $header  Additional Header(s)
+     * @param string|null $params  Params
+     *
+     * @return bool
+     */
+    private function mailPassthru($to, $subject, $body, $header, $params)
+    {
+        //Check overloading of mail function to avoid double-encoding
+        if ((int)ini_get('mbstring.func_overload') & 1) {
+            $subject = $this->secureHeader($subject);
+        } else {
+            $subject = $this->encodeHeader($this->secureHeader($subject));
+        }
+        //Calling mail() with null params breaks
+        $this->edebug('Sending with mail()');
+        $this->edebug('Sendmail path: ' . ini_get('sendmail_path'));
+        $this->edebug("Envelope sender: {$this->Sender}");
+        $this->edebug("To: {$to}");
+        $this->edebug("Subject: {$subject}");
+        $this->edebug("Headers: {$header}");
+        if (!$this->UseSendmailOptions || null === $params) {
+            $result = @mail($to, $subject, $body, $header);
+        } else {
+            $this->edebug("Additional params: {$params}");
+            $result = @mail($to, $subject, $body, $header, $params);
+        }
+        $this->edebug('Result: ' . ($result ? 'true' : 'false'));
+        return $result;
+    }
+
+    /**
+     * Output debugging info via a user-defined method.
+     * Only generates output if debug output is enabled.
+     *
+     * @see PHPMailer::$Debugoutput
+     * @see PHPMailer::$SMTPDebug
+     *
+     * @param string $str
+     */
+    protected function edebug($str)
+    {
+        if ($this->SMTPDebug <= 0) {
+            return;
+        }
+        //Is this a PSR-3 logger?
+        if ($this->Debugoutput instanceof \Psr\Log\LoggerInterface) {
+            $this->Debugoutput->debug($str);
+
+            return;
+        }
+        //Avoid clash with built-in function names
+        if (is_callable($this->Debugoutput) && !in_array($this->Debugoutput, ['error_log', 'html', 'echo'])) {
+            call_user_func($this->Debugoutput, $str, $this->SMTPDebug);
+
+            return;
+        }
+        switch ($this->Debugoutput) {
+            case 'error_log':
+                //Don't output, just log
+                /** @noinspection ForgottenDebugOutputInspection */
+                error_log($str);
+                break;
+            case 'html':
+                //Cleans up output a bit for a better looking, HTML-safe output
+                echo htmlentities(
+                    preg_replace('/[\r\n]+/', '', $str),
+                    ENT_QUOTES,
+                    'UTF-8'
+                ), "<br>\n";
+                break;
+            case 'echo':
+            default:
+                //Normalize line breaks
+                $str = preg_replace('/\r\n|\r/m', "\n", $str);
+                echo gmdate('Y-m-d H:i:s'),
+                "\t",
+                    //Trim trailing space
+                trim(
+                    //Indent for readability, except for trailing break
+                    str_replace(
+                        "\n",
+                        "\n                   \t                  ",
+                        trim($str)
+                    )
+                ),
+                "\n";
+        }
+    }
+
+    /**
+     * Sets message type to HTML or plain.
+     *
+     * @param bool $isHtml True for HTML mode
+     */
+    public function isHTML($isHtml = true)
+    {
+        if ($isHtml) {
+            $this->ContentType = static::CONTENT_TYPE_TEXT_HTML;
+        } else {
+            $this->ContentType = static::CONTENT_TYPE_PLAINTEXT;
+        }
+    }
+
+    /**
+     * Send messages using SMTP.
+     */
+    public function isSMTP()
+    {
+        $this->Mailer = 'smtp';
+    }
+
+    /**
+     * Send messages using PHP's mail() function.
+     */
+    public function isMail()
+    {
+        $this->Mailer = 'mail';
+    }
+
+    /**
+     * Send messages using $Sendmail.
+     */
+    public function isSendmail()
+    {
+        $ini_sendmail_path = ini_get('sendmail_path');
+
+        if (false === stripos($ini_sendmail_path, 'sendmail')) {
+            $this->Sendmail = '/usr/sbin/sendmail';
+        } else {
+            $this->Sendmail = $ini_sendmail_path;
+        }
+        $this->Mailer = 'sendmail';
+    }
+
+    /**
+     * Send messages using qmail.
+     */
+    public function isQmail()
+    {
+        $ini_sendmail_path = ini_get('sendmail_path');
+
+        if (false === stripos($ini_sendmail_path, 'qmail')) {
+            $this->Sendmail = '/var/qmail/bin/qmail-inject';
+        } else {
+            $this->Sendmail = $ini_sendmail_path;
+        }
+        $this->Mailer = 'qmail';
+    }
+
+    /**
+     * Add a "To" address.
+     *
+     * @param string $address The email address to send to
+     * @param string $name
+     *
+     * @throws Exception
+     *
+     * @return bool true on success, false if address already used or invalid in some way
+     */
+    public function addAddress($address, $name = '')
+    {
+        return $this->addOrEnqueueAnAddress('to', $address, $name);
+    }
+
+    /**
+     * Add a "CC" address.
+     *
+     * @param string $address The email address to send to
+     * @param string $name
+     *
+     * @throws Exception
+     *
+     * @return bool true on success, false if address already used or invalid in some way
+     */
+    public function addCC($address, $name = '')
+    {
+        return $this->addOrEnqueueAnAddress('cc', $address, $name);
+    }
+
+    /**
+     * Add a "BCC" address.
+     *
+     * @param string $address The email address to send to
+     * @param string $name
+     *
+     * @throws Exception
+     *
+     * @return bool true on success, false if address already used or invalid in some way
+     */
+    public function addBCC($address, $name = '')
+    {
+        return $this->addOrEnqueueAnAddress('bcc', $address, $name);
+    }
+
+    /**
+     * Add a "Reply-To" address.
+     *
+     * @param string $address The email address to reply to
+     * @param string $name
+     *
+     * @throws Exception
+     *
+     * @return bool true on success, false if address already used or invalid in some way
+     */
+    public function addReplyTo($address, $name = '')
+    {
+        return $this->addOrEnqueueAnAddress('Reply-To', $address, $name);
+    }
+
+    /**
+     * Add an address to one of the recipient arrays or to the ReplyTo array. Because PHPMailer
+     * can't validate addresses with an IDN without knowing the PHPMailer::$CharSet (that can still
+     * be modified after calling this function), addition of such addresses is delayed until send().
+     * Addresses that have been added already return false, but do not throw exceptions.
+     *
+     * @param string $kind    One of 'to', 'cc', 'bcc', or 'ReplyTo'
+     * @param string $address The email address
+     * @param string $name    An optional username associated with the address
+     *
+     * @throws Exception
+     *
+     * @return bool true on success, false if address already used or invalid in some way
+     */
+    protected function addOrEnqueueAnAddress($kind, $address, $name)
+    {
+        $pos = false;
+        if ($address !== null) {
+            $address = trim($address);
+            $pos = strrpos($address, '@');
+        }
+        if (false === $pos) {
+            //At-sign is missing.
+            $error_message = sprintf(
+                '%s (%s): %s',
+                $this->lang('invalid_address'),
+                $kind,
+                $address
+            );
+            $this->setError($error_message);
+            $this->edebug($error_message);
+            if ($this->exceptions) {
+                throw new Exception($error_message);
+            }
+
+            return false;
+        }
+        if ($name !== null && is_string($name)) {
+            $name = trim(preg_replace('/[\r\n]+/', '', $name)); //Strip breaks and trim
+        } else {
+            $name = '';
+        }
+        $params = [$kind, $address, $name];
+        //Enqueue addresses with IDN until we know the PHPMailer::$CharSet.
+        //Domain is assumed to be whatever is after the last @ symbol in the address
+        if (static::idnSupported() && $this->has8bitChars(substr($address, ++$pos))) {
+            if ('Reply-To' !== $kind) {
+                if (!array_key_exists($address, $this->RecipientsQueue)) {
+                    $this->RecipientsQueue[$address] = $params;
+
+                    return true;
+                }
+            } elseif (!array_key_exists($address, $this->ReplyToQueue)) {
+                $this->ReplyToQueue[$address] = $params;
+
+                return true;
+            }
+
+            return false;
+        }
+
+        //Immediately add standard addresses without IDN.
+        return call_user_func_array([$this, 'addAnAddress'], $params);
+    }
+
+    /**
+     * Set the boundaries to use for delimiting MIME parts.
+     * If you override this, ensure you set all 3 boundaries to unique values.
+     * The default boundaries include a "=_" sequence which cannot occur in quoted-printable bodies,
+     * as suggested by https://www.rfc-editor.org/rfc/rfc2045#section-6.7
+     *
+     * @return void
+     */
+    public function setBoundaries()
+    {
+        $this->uniqueid = $this->generateId();
+        $this->boundary[1] = 'b1=_' . $this->uniqueid;
+        $this->boundary[2] = 'b2=_' . $this->uniqueid;
+        $this->boundary[3] = 'b3=_' . $this->uniqueid;
+    }
+
+    /**
+     * Add an address to one of the recipient arrays or to the ReplyTo array.
+     * Addresses that have been added already return false, but do not throw exceptions.
+     *
+     * @param string $kind    One of 'to', 'cc', 'bcc', or 'ReplyTo'
+     * @param string $address The email address to send, resp. to reply to
+     * @param string $name
+     *
+     * @throws Exception
+     *
+     * @return bool true on success, false if address already used or invalid in some way
+     */
+    protected function addAnAddress($kind, $address, $name = '')
+    {
+        if (!in_array($kind, ['to', 'cc', 'bcc', 'Reply-To'])) {
+            $error_message = sprintf(
+                '%s: %s',
+                $this->lang('Invalid recipient kind'),
+                $kind
+            );
+            $this->setError($error_message);
+            $this->edebug($error_message);
+            if ($this->exceptions) {
+                throw new Exception($error_message);
+            }
+
+            return false;
+        }
+        if (!static::validateAddress($address)) {
+            $error_message = sprintf(
+                '%s (%s): %s',
+                $this->lang('invalid_address'),
+                $kind,
+                $address
+            );
+            $this->setError($error_message);
+            $this->edebug($error_message);
+            if ($this->exceptions) {
+                throw new Exception($error_message);
+            }
+
+            return false;
+        }
+        if ('Reply-To' !== $kind) {
+            if (!array_key_exists(strtolower($address), $this->all_recipients)) {
+                $this->{$kind}[] = [$address, $name];
+                $this->all_recipients[strtolower($address)] = true;
+
+                return true;
+            }
+        } elseif (!array_key_exists(strtolower($address), $this->ReplyTo)) {
+            $this->ReplyTo[strtolower($address)] = [$address, $name];
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Parse and validate a string containing one or more RFC822-style comma-separated email addresses
+     * of the form "display name <address>" into an array of name/address pairs.
+     * Uses the imap_rfc822_parse_adrlist function if the IMAP extension is available.
+     * Note that quotes in the name part are removed.
+     *
+     * @see http://www.andrew.cmu.edu/user/agreen1/testing/mrbs/web/Mail/RFC822.php A more careful implementation
+     *
+     * @param string $addrstr The address list string
+     * @param bool   $useimap Whether to use the IMAP extension to parse the list
+     * @param string $charset The charset to use when decoding the address list string.
+     *
+     * @return array
+     */
+    public static function parseAddresses($addrstr, $useimap = true, $charset = self::CHARSET_ISO88591)
+    {
+        $addresses = [];
+        if ($useimap && function_exists('imap_rfc822_parse_adrlist')) {
+            //Use this built-in parser if it's available
+            $list = imap_rfc822_parse_adrlist($addrstr, '');
+            // Clear any potential IMAP errors to get rid of notices being thrown at end of script.
+            imap_errors();
+            foreach ($list as $address) {
+                if (
+                    '.SYNTAX-ERROR.' !== $address->host &&
+                    static::validateAddress($address->mailbox . '@' . $address->host)
+                ) {
+                    //Decode the name part if it's present and encoded
+                    if (
+                        property_exists($address, 'personal') &&
+                        //Check for a Mbstring constant rather than using extension_loaded, which is sometimes disabled
+                        defined('MB_CASE_UPPER') &&
+                        preg_match('/^=\?.*\?=$/s', $address->personal)
+                    ) {
+                        $origCharset = mb_internal_encoding();
+                        mb_internal_encoding($charset);
+                        //Undo any RFC2047-encoded spaces-as-underscores
+                        $address->personal = str_replace('_', '=20', $address->personal);
+                        //Decode the name
+                        $address->personal = mb_decode_mimeheader($address->personal);
+                        mb_internal_encoding($origCharset);
+                    }
+
+                    $addresses[] = [
+                        'name' => (property_exists($address, 'personal') ? $address->personal : ''),
+                        'address' => $address->mailbox . '@' . $address->host,
+                    ];
+                }
+            }
+        } else {
+            //Use this simpler parser
+            $list = explode(',', $addrstr);
+            foreach ($list as $address) {
+                $address = trim($address);
+                //Is there a separate name part?
+                if (strpos($address, '<') === false) {
+                    //No separate name, just use the whole thing
+                    if (static::validateAddress($address)) {
+                        $addresses[] = [
+                            'name' => '',
+                            'address' => $address,
+                        ];
+                    }
+                } else {
+                    list($name, $email) = explode('<', $address);
+                    $email = trim(str_replace('>', '', $email));
+                    $name = trim($name);
+                    if (static::validateAddress($email)) {
+                        //Check for a Mbstring constant rather than using extension_loaded, which is sometimes disabled
+                        //If this name is encoded, decode it
+                        if (defined('MB_CASE_UPPER') && preg_match('/^=\?.*\?=$/s', $name)) {
+                            $origCharset = mb_internal_encoding();
+                            mb_internal_encoding($charset);
+                            //Undo any RFC2047-encoded spaces-as-underscores
+                            $name = str_replace('_', '=20', $name);
+                            //Decode the name
+                            $name = mb_decode_mimeheader($name);
+                            mb_internal_encoding($origCharset);
+                        }
+                        $addresses[] = [
+                            //Remove any surrounding quotes and spaces from the name
+                            'name' => trim($name, '\'" '),
+                            'address' => $email,
+                        ];
+                    }
+                }
+            }
+        }
+
+        return $addresses;
+    }
+
+    /**
+     * Set the From and FromName properties.
+     *
+     * @param string $address
+     * @param string $name
+     * @param bool   $auto    Whether to also set the Sender address, defaults to true
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    public function setFrom($address, $name = '', $auto = true)
+    {
+        $address = trim((string)$address);
+        $name = trim(preg_replace('/[\r\n]+/', '', $name)); //Strip breaks and trim
+        //Don't validate now addresses with IDN. Will be done in send().
+        $pos = strrpos($address, '@');
+        if (
+            (false === $pos)
+            || ((!$this->has8bitChars(substr($address, ++$pos)) || !static::idnSupported())
+            && !static::validateAddress($address))
+        ) {
+            $error_message = sprintf(
+                '%s (From): %s',
+                $this->lang('invalid_address'),
+                $address
+            );
+            $this->setError($error_message);
+            $this->edebug($error_message);
+            if ($this->exceptions) {
+                throw new Exception($error_message);
+            }
+
+            return false;
+        }
+        $this->From = $address;
+        $this->FromName = $name;
+        if ($auto && empty($this->Sender)) {
+            $this->Sender = $address;
+        }
+
+        return true;
+    }
+
+    /**
+     * Return the Message-ID header of the last email.
+     * Technically this is the value from the last time the headers were created,
+     * but it's also the message ID of the last sent message except in
+     * pathological cases.
+     *
+     * @return string
+     */
+    public function getLastMessageID()
+    {
+        return $this->lastMessageID;
+    }
+
+    /**
+     * Check that a string looks like an email address.
+     * Validation patterns supported:
+     * * `auto` Pick best pattern automatically;
+     * * `pcre8` Use the squiloople.com pattern, requires PCRE > 8.0;
+     * * `pcre` Use old PCRE implementation;
+     * * `php` Use PHP built-in FILTER_VALIDATE_EMAIL;
+     * * `html5` Use the pattern given by the HTML5 spec for 'email' type form input elements.
+     * * `noregex` Don't use a regex: super fast, really dumb.
+     * Alternatively you may pass in a callable to inject your own validator, for example:
+     *
+     * ```php
+     * PHPMailer::validateAddress('user@example.com', function($address) {
+     *     return (strpos($address, '@') !== false);
+     * });
+     * ```
+     *
+     * You can also set the PHPMailer::$validator static to a callable, allowing built-in methods to use your validator.
+     *
+     * @param string          $address       The email address to check
+     * @param string|callable $patternselect Which pattern to use
+     *
+     * @return bool
+     */
+    public static function validateAddress($address, $patternselect = null)
+    {
+        if (null === $patternselect) {
+            $patternselect = static::$validator;
+        }
+        //Don't allow strings as callables, see SECURITY.md and CVE-2021-3603
+        if (is_callable($patternselect) && !is_string($patternselect)) {
+            return call_user_func($patternselect, $address);
+        }
+        //Reject line breaks in addresses; it's valid RFC5322, but not RFC5321
+        if (strpos($address, "\n") !== false || strpos($address, "\r") !== false) {
+            return false;
+        }
+        switch ($patternselect) {
+            case 'pcre': //Kept for BC
+            case 'pcre8':
+                /*
+                 * A more complex and more permissive version of the RFC5322 regex on which FILTER_VALIDATE_EMAIL
+                 * is based.
+                 * In addition to the addresses allowed by filter_var, also permits:
+                 *  * dotless domains: `a@b`
+                 *  * comments: `1234 @ local(blah) .machine .example`
+                 *  * quoted elements: `'"test blah"@example.org'`
+                 *  * numeric TLDs: `a@b.123`
+                 *  * unbracketed IPv4 literals: `a@192.168.0.1`
+                 *  * IPv6 literals: 'first.last@[IPv6:a1::]'
+                 * Not all of these will necessarily work for sending!
+                 *
+                 * @see       http://squiloople.com/2009/12/20/email-address-validation/
+                 * @copyright 2009-2010 Michael Rushton
+                 * Feel free to use and redistribute this code. But please keep this copyright notice.
+                 */
+                return (bool) preg_match(
+                    '/^(?!(?>(?1)"?(?>\\\[ -~]|[^"])"?(?1)){255,})(?!(?>(?1)"?(?>\\\[ -~]|[^"])"?(?1)){65,}@)' .
+                    '((?>(?>(?>((?>(?>(?>\x0D\x0A)?[\t ])+|(?>[\t ]*\x0D\x0A)?[\t ]+)?)(\((?>(?2)' .
+                    '(?>[\x01-\x08\x0B\x0C\x0E-\'*-\[\]-\x7F]|\\\[\x00-\x7F]|(?3)))*(?2)\)))+(?2))|(?2))?)' .
+                    '([!#-\'*+\/-9=?^-~-]+|"(?>(?2)(?>[\x01-\x08\x0B\x0C\x0E-!#-\[\]-\x7F]|\\\[\x00-\x7F]))*' .
+                    '(?2)")(?>(?1)\.(?1)(?4))*(?1)@(?!(?1)[a-z0-9-]{64,})(?1)(?>([a-z0-9](?>[a-z0-9-]*[a-z0-9])?)' .
+                    '(?>(?1)\.(?!(?1)[a-z0-9-]{64,})(?1)(?5)){0,126}|\[(?:(?>IPv6:(?>([a-f0-9]{1,4})(?>:(?6)){7}' .
+                    '|(?!(?:.*[a-f0-9][:\]]){8,})((?6)(?>:(?6)){0,6})?::(?7)?))|(?>(?>IPv6:(?>(?6)(?>:(?6)){5}:' .
+                    '|(?!(?:.*[a-f0-9]:){6,})(?8)?::(?>((?6)(?>:(?6)){0,4}):)?))?(25[0-5]|2[0-4][0-9]|1[0-9]{2}' .
+                    '|[1-9]?[0-9])(?>\.(?9)){3}))\])(?1)$/isD',
+                    $address
+                );
+            case 'html5':
+                /*
+                 * This is the pattern used in the HTML5 spec for validation of 'email' type form input elements.
+                 *
+                 * @see https://html.spec.whatwg.org/#e-mail-state-(type=email)
+                 */
+                return (bool) preg_match(
+                    '/^[a-zA-Z0-9.!#$%&\'*+\/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}' .
+                    '[a-zA-Z0-9])?(?:\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$/sD',
+                    $address
+                );
+            case 'php':
+            default:
+                return filter_var($address, FILTER_VALIDATE_EMAIL) !== false;
+        }
+    }
+
+    /**
+     * Tells whether IDNs (Internationalized Domain Names) are supported or not. This requires the
+     * `intl` and `mbstring` PHP extensions.
+     *
+     * @return bool `true` if required functions for IDN support are present
+     */
+    public static function idnSupported()
+    {
+        return function_exists('idn_to_ascii') && function_exists('mb_convert_encoding');
+    }
+
+    /**
+     * Converts IDN in given email address to its ASCII form, also known as punycode, if possible.
+     * Important: Address must be passed in same encoding as currently set in PHPMailer::$CharSet.
+     * This function silently returns unmodified address if:
+     * - No conversion is necessary (i.e. domain name is not an IDN, or is already in ASCII form)
+     * - Conversion to punycode is impossible (e.g. required PHP functions are not available)
+     *   or fails for any reason (e.g. domain contains characters not allowed in an IDN).
+     *
+     * @see PHPMailer::$CharSet
+     *
+     * @param string $address The email address to convert
+     *
+     * @return string The encoded address in ASCII form
+     */
+    public function punyencodeAddress($address)
+    {
+        //Verify we have required functions, CharSet, and at-sign.
+        $pos = strrpos($address, '@');
+        if (
+            !empty($this->CharSet) &&
+            false !== $pos &&
+            static::idnSupported()
+        ) {
+            $domain = substr($address, ++$pos);
+            //Verify CharSet string is a valid one, and domain properly encoded in this CharSet.
+            if ($this->has8bitChars($domain) && @mb_check_encoding($domain, $this->CharSet)) {
+                //Convert the domain from whatever charset it's in to UTF-8
+                $domain = mb_convert_encoding($domain, self::CHARSET_UTF8, $this->CharSet);
+                //Ignore IDE complaints about this line - method signature changed in PHP 5.4
+                $errorcode = 0;
+                if (defined('INTL_IDNA_VARIANT_UTS46')) {
+                    //Use the current punycode standard (appeared in PHP 7.2)
+                    $punycode = idn_to_ascii(
+                        $domain,
+                        \IDNA_DEFAULT | \IDNA_USE_STD3_RULES | \IDNA_CHECK_BIDI |
+                            \IDNA_CHECK_CONTEXTJ | \IDNA_NONTRANSITIONAL_TO_ASCII,
+                        \INTL_IDNA_VARIANT_UTS46
+                    );
+                } elseif (defined('INTL_IDNA_VARIANT_2003')) {
+                    //Fall back to this old, deprecated/removed encoding
+                    $punycode = idn_to_ascii($domain, $errorcode, \INTL_IDNA_VARIANT_2003);
+                } else {
+                    //Fall back to a default we don't know about
+                    $punycode = idn_to_ascii($domain, $errorcode);
+                }
+                if (false !== $punycode) {
+                    return substr($address, 0, $pos) . $punycode;
+                }
+            }
+        }
+
+        return $address;
+    }
+
+    /**
+     * Create a message and send it.
+     * Uses the sending method specified by $Mailer.
+     *
+     * @throws Exception
+     *
+     * @return bool false on error - See the ErrorInfo property for details of the error
+     */
+    public function send()
+    {
+        try {
+            if (!$this->preSend()) {
+                return false;
+            }
+
+            return $this->postSend();
+        } catch (Exception $exc) {
+            $this->mailHeader = '';
+            $this->setError($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return false;
+        }
+    }
+
+    /**
+     * Prepare a message for sending.
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    public function preSend()
+    {
+        if (
+            'smtp' === $this->Mailer
+            || ('mail' === $this->Mailer && (\PHP_VERSION_ID >= 80000 || stripos(PHP_OS, 'WIN') === 0))
+        ) {
+            //SMTP mandates RFC-compliant line endings
+            //and it's also used with mail() on Windows
+            static::setLE(self::CRLF);
+        } else {
+            //Maintain backward compatibility with legacy Linux command line mailers
+            static::setLE(PHP_EOL);
+        }
+        //Check for buggy PHP versions that add a header with an incorrect line break
+        if (
+            'mail' === $this->Mailer
+            && ((\PHP_VERSION_ID >= 70000 && \PHP_VERSION_ID < 70017)
+                || (\PHP_VERSION_ID >= 70100 && \PHP_VERSION_ID < 70103))
+            && ini_get('mail.add_x_header') === '1'
+            && stripos(PHP_OS, 'WIN') === 0
+        ) {
+            trigger_error($this->lang('buggy_php'), E_USER_WARNING);
+        }
+
+        try {
+            $this->error_count = 0; //Reset errors
+            $this->mailHeader = '';
+
+            //Dequeue recipient and Reply-To addresses with IDN
+            foreach (array_merge($this->RecipientsQueue, $this->ReplyToQueue) as $params) {
+                $params[1] = $this->punyencodeAddress($params[1]);
+                call_user_func_array([$this, 'addAnAddress'], $params);
+            }
+            if (count($this->to) + count($this->cc) + count($this->bcc) < 1) {
+                throw new Exception($this->lang('provide_address'), self::STOP_CRITICAL);
+            }
+
+            //Validate From, Sender, and ConfirmReadingTo addresses
+            foreach (['From', 'Sender', 'ConfirmReadingTo'] as $address_kind) {
+                $this->{$address_kind} = trim($this->{$address_kind});
+                if (empty($this->{$address_kind})) {
+                    continue;
+                }
+                $this->{$address_kind} = $this->punyencodeAddress($this->{$address_kind});
+                if (!static::validateAddress($this->{$address_kind})) {
+                    $error_message = sprintf(
+                        '%s (%s): %s',
+                        $this->lang('invalid_address'),
+                        $address_kind,
+                        $this->{$address_kind}
+                    );
+                    $this->setError($error_message);
+                    $this->edebug($error_message);
+                    if ($this->exceptions) {
+                        throw new Exception($error_message);
+                    }
+
+                    return false;
+                }
+            }
+
+            //Set whether the message is multipart/alternative
+            if ($this->alternativeExists()) {
+                $this->ContentType = static::CONTENT_TYPE_MULTIPART_ALTERNATIVE;
+            }
+
+            $this->setMessageType();
+            //Refuse to send an empty message unless we are specifically allowing it
+            if (!$this->AllowEmpty && empty($this->Body)) {
+                throw new Exception($this->lang('empty_message'), self::STOP_CRITICAL);
+            }
+
+            //Trim subject consistently
+            $this->Subject = trim($this->Subject);
+            //Create body before headers in case body makes changes to headers (e.g. altering transfer encoding)
+            $this->MIMEHeader = '';
+            $this->MIMEBody = $this->createBody();
+            //createBody may have added some headers, so retain them
+            $tempheaders = $this->MIMEHeader;
+            $this->MIMEHeader = $this->createHeader();
+            $this->MIMEHeader .= $tempheaders;
+
+            //To capture the complete message when using mail(), create
+            //an extra header list which createHeader() doesn't fold in
+            if ('mail' === $this->Mailer) {
+                if (count($this->to) > 0) {
+                    $this->mailHeader .= $this->addrAppend('To', $this->to);
+                } else {
+                    $this->mailHeader .= $this->headerLine('To', 'undisclosed-recipients:;');
+                }
+                $this->mailHeader .= $this->headerLine(
+                    'Subject',
+                    $this->encodeHeader($this->secureHeader($this->Subject))
+                );
+            }
+
+            //Sign with DKIM if enabled
+            if (
+                !empty($this->DKIM_domain)
+                && !empty($this->DKIM_selector)
+                && (!empty($this->DKIM_private_string)
+                    || (!empty($this->DKIM_private)
+                        && static::isPermittedPath($this->DKIM_private)
+                        && file_exists($this->DKIM_private)
+                    )
+                )
+            ) {
+                $header_dkim = $this->DKIM_Add(
+                    $this->MIMEHeader . $this->mailHeader,
+                    $this->encodeHeader($this->secureHeader($this->Subject)),
+                    $this->MIMEBody
+                );
+                $this->MIMEHeader = static::stripTrailingWSP($this->MIMEHeader) . static::$LE .
+                    static::normalizeBreaks($header_dkim) . static::$LE;
+            }
+
+            return true;
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return false;
+        }
+    }
+
+    /**
+     * Actually send a message via the selected mechanism.
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    public function postSend()
+    {
+        try {
+            //Choose the mailer and send through it
+            switch ($this->Mailer) {
+                case 'sendmail':
+                case 'qmail':
+                    return $this->sendmailSend($this->MIMEHeader, $this->MIMEBody);
+                case 'smtp':
+                    return $this->smtpSend($this->MIMEHeader, $this->MIMEBody);
+                case 'mail':
+                    return $this->mailSend($this->MIMEHeader, $this->MIMEBody);
+                default:
+                    $sendMethod = $this->Mailer . 'Send';
+                    if (method_exists($this, $sendMethod)) {
+                        return $this->{$sendMethod}($this->MIMEHeader, $this->MIMEBody);
+                    }
+
+                    return $this->mailSend($this->MIMEHeader, $this->MIMEBody);
+            }
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            $this->edebug($exc->getMessage());
+            if ($this->Mailer === 'smtp' && $this->SMTPKeepAlive == true && $this->smtp->connected()) {
+                $this->smtp->reset();
+            }
+            if ($this->exceptions) {
+                throw $exc;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Send mail using the $Sendmail program.
+     *
+     * @see PHPMailer::$Sendmail
+     *
+     * @param string $header The message headers
+     * @param string $body   The message body
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    protected function sendmailSend($header, $body)
+    {
+        if ($this->Mailer === 'qmail') {
+            $this->edebug('Sending with qmail');
+        } else {
+            $this->edebug('Sending with sendmail');
+        }
+        $header = static::stripTrailingWSP($header) . static::$LE . static::$LE;
+        //This sets the SMTP envelope sender which gets turned into a return-path header by the receiver
+        //A space after `-f` is optional, but there is a long history of its presence
+        //causing problems, so we don't use one
+        //Exim docs: http://www.exim.org/exim-html-current/doc/html/spec_html/ch-the_exim_command_line.html
+        //Sendmail docs: http://www.sendmail.org/~ca/email/man/sendmail.html
+        //Qmail docs: http://www.qmail.org/man/man8/qmail-inject.html
+        //Example problem: https://www.drupal.org/node/1057954
+
+        //PHP 5.6 workaround
+        $sendmail_from_value = ini_get('sendmail_from');
+        if (empty($this->Sender) && !empty($sendmail_from_value)) {
+            //PHP config has a sender address we can use
+            $this->Sender = ini_get('sendmail_from');
+        }
+        //CVE-2016-10033, CVE-2016-10045: Don't pass -f if characters will be escaped.
+        if (!empty($this->Sender) && static::validateAddress($this->Sender) && self::isShellSafe($this->Sender)) {
+            if ($this->Mailer === 'qmail') {
+                $sendmailFmt = '%s -f%s';
+            } else {
+                $sendmailFmt = '%s -oi -f%s -t';
+            }
+        } else {
+            //allow sendmail to choose a default envelope sender. It may
+            //seem preferable to force it to use the From header as with
+            //SMTP, but that introduces new problems (see
+            //<https://github.com/PHPMailer/PHPMailer/issues/2298>), and
+            //it has historically worked this way.
+            $sendmailFmt = '%s -oi -t';
+        }
+
+        $sendmail = sprintf($sendmailFmt, escapeshellcmd($this->Sendmail), $this->Sender);
+        $this->edebug('Sendmail path: ' . $this->Sendmail);
+        $this->edebug('Sendmail command: ' . $sendmail);
+        $this->edebug('Envelope sender: ' . $this->Sender);
+        $this->edebug("Headers: {$header}");
+
+        if ($this->SingleTo) {
+            foreach ($this->SingleToArray as $toAddr) {
+                $mail = @popen($sendmail, 'w');
+                if (!$mail) {
+                    throw new Exception($this->lang('execute') . $this->Sendmail, self::STOP_CRITICAL);
+                }
+                $this->edebug("To: {$toAddr}");
+                fwrite($mail, 'To: ' . $toAddr . "\n");
+                fwrite($mail, $header);
+                fwrite($mail, $body);
+                $result = pclose($mail);
+                $addrinfo = static::parseAddresses($toAddr, true, $this->CharSet);
+                $this->doCallback(
+                    ($result === 0),
+                    [[$addrinfo['address'], $addrinfo['name']]],
+                    $this->cc,
+                    $this->bcc,
+                    $this->Subject,
+                    $body,
+                    $this->From,
+                    []
+                );
+                $this->edebug("Result: " . ($result === 0 ? 'true' : 'false'));
+                if (0 !== $result) {
+                    throw new Exception($this->lang('execute') . $this->Sendmail, self::STOP_CRITICAL);
+                }
+            }
+        } else {
+            $mail = @popen($sendmail, 'w');
+            if (!$mail) {
+                throw new Exception($this->lang('execute') . $this->Sendmail, self::STOP_CRITICAL);
+            }
+            fwrite($mail, $header);
+            fwrite($mail, $body);
+            $result = pclose($mail);
+            $this->doCallback(
+                ($result === 0),
+                $this->to,
+                $this->cc,
+                $this->bcc,
+                $this->Subject,
+                $body,
+                $this->From,
+                []
+            );
+            $this->edebug("Result: " . ($result === 0 ? 'true' : 'false'));
+            if (0 !== $result) {
+                throw new Exception($this->lang('execute') . $this->Sendmail, self::STOP_CRITICAL);
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Fix CVE-2016-10033 and CVE-2016-10045 by disallowing potentially unsafe shell characters.
+     * Note that escapeshellarg and escapeshellcmd are inadequate for our purposes, especially on Windows.
+     *
+     * @see https://github.com/PHPMailer/PHPMailer/issues/924 CVE-2016-10045 bug report
+     *
+     * @param string $string The string to be validated
+     *
+     * @return bool
+     */
+    protected static function isShellSafe($string)
+    {
+        //It's not possible to use shell commands safely (which includes the mail() function) without escapeshellarg,
+        //but some hosting providers disable it, creating a security problem that we don't want to have to deal with,
+        //so we don't.
+        if (!function_exists('escapeshellarg') || !function_exists('escapeshellcmd')) {
+            return false;
+        }
+
+        if (
+            escapeshellcmd($string) !== $string
+            || !in_array(escapeshellarg($string), ["'$string'", "\"$string\""])
+        ) {
+            return false;
+        }
+
+        $length = strlen($string);
+
+        for ($i = 0; $i < $length; ++$i) {
+            $c = $string[$i];
+
+            //All other characters have a special meaning in at least one common shell, including = and +.
+            //Full stop (.) has a special meaning in cmd.exe, but its impact should be negligible here.
+            //Note that this does permit non-Latin alphanumeric characters based on the current locale.
+            if (!ctype_alnum($c) && strpos('@_-.', $c) === false) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Check whether a file path is of a permitted type.
+     * Used to reject URLs and phar files from functions that access local file paths,
+     * such as addAttachment.
+     *
+     * @param string $path A relative or absolute path to a file
+     *
+     * @return bool
+     */
+    protected static function isPermittedPath($path)
+    {
+        //Matches scheme definition from https://tools.ietf.org/html/rfc3986#section-3.1
+        return !preg_match('#^[a-z][a-z\d+.-]*://#i', $path);
+    }
+
+    /**
+     * Check whether a file path is safe, accessible, and readable.
+     *
+     * @param string $path A relative or absolute path to a file
+     *
+     * @return bool
+     */
+    protected static function fileIsAccessible($path)
+    {
+        if (!static::isPermittedPath($path)) {
+            return false;
+        }
+        $readable = is_file($path);
+        //If not a UNC path (expected to start with \\), check read permission, see #2069
+        if (strpos($path, '\\\\') !== 0) {
+            $readable = $readable && is_readable($path);
+        }
+        return  $readable;
+    }
+
+    /**
+     * Send mail using the PHP mail() function.
+     *
+     * @see http://www.php.net/manual/en/book.mail.php
+     *
+     * @param string $header The message headers
+     * @param string $body   The message body
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    protected function mailSend($header, $body)
+    {
+        $header = static::stripTrailingWSP($header) . static::$LE . static::$LE;
+
+        $toArr = [];
+        foreach ($this->to as $toaddr) {
+            $toArr[] = $this->addrFormat($toaddr);
+        }
+        $to = trim(implode(', ', $toArr));
+
+        //If there are no To-addresses (e.g. when sending only to BCC-addresses)
+        //the following should be added to get a correct DKIM-signature.
+        //Compare with $this->preSend()
+        if ($to === '') {
+            $to = 'undisclosed-recipients:;';
+        }
+
+        $params = null;
+        //This sets the SMTP envelope sender which gets turned into a return-path header by the receiver
+        //A space after `-f` is optional, but there is a long history of its presence
+        //causing problems, so we don't use one
+        //Exim docs: http://www.exim.org/exim-html-current/doc/html/spec_html/ch-the_exim_command_line.html
+        //Sendmail docs: http://www.sendmail.org/~ca/email/man/sendmail.html
+        //Qmail docs: http://www.qmail.org/man/man8/qmail-inject.html
+        //Example problem: https://www.drupal.org/node/1057954
+        //CVE-2016-10033, CVE-2016-10045: Don't pass -f if characters will be escaped.
+
+        //PHP 5.6 workaround
+        $sendmail_from_value = ini_get('sendmail_from');
+        if (empty($this->Sender) && !empty($sendmail_from_value)) {
+            //PHP config has a sender address we can use
+            $this->Sender = ini_get('sendmail_from');
+        }
+        if (!empty($this->Sender) && static::validateAddress($this->Sender)) {
+            if (self::isShellSafe($this->Sender)) {
+                $params = sprintf('-f%s', $this->Sender);
+            }
+            $old_from = ini_get('sendmail_from');
+            ini_set('sendmail_from', $this->Sender);
+        }
+        $result = false;
+        if ($this->SingleTo && count($toArr) > 1) {
+            foreach ($toArr as $toAddr) {
+                $result = $this->mailPassthru($toAddr, $this->Subject, $body, $header, $params);
+                $addrinfo = static::parseAddresses($toAddr, true, $this->CharSet);
+                $this->doCallback(
+                    $result,
+                    [[$addrinfo['address'], $addrinfo['name']]],
+                    $this->cc,
+                    $this->bcc,
+                    $this->Subject,
+                    $body,
+                    $this->From,
+                    []
+                );
+            }
+        } else {
+            $result = $this->mailPassthru($to, $this->Subject, $body, $header, $params);
+            $this->doCallback($result, $this->to, $this->cc, $this->bcc, $this->Subject, $body, $this->From, []);
+        }
+        if (isset($old_from)) {
+            ini_set('sendmail_from', $old_from);
+        }
+        if (!$result) {
+            throw new Exception($this->lang('instantiate'), self::STOP_CRITICAL);
+        }
+
+        return true;
+    }
+
+    /**
+     * Get an instance to use for SMTP operations.
+     * Override this function to load your own SMTP implementation,
+     * or set one with setSMTPInstance.
+     *
+     * @return SMTP
+     */
+    public function getSMTPInstance()
+    {
+        if (!is_object($this->smtp)) {
+            $this->smtp = new SMTP();
+        }
+
+        return $this->smtp;
+    }
+
+    /**
+     * Provide an instance to use for SMTP operations.
+     *
+     * @return SMTP
+     */
+    public function setSMTPInstance(SMTP $smtp)
+    {
+        $this->smtp = $smtp;
+
+        return $this->smtp;
+    }
+
+    /**
+     * Send mail via SMTP.
+     * Returns false if there is a bad MAIL FROM, RCPT, or DATA input.
+     *
+     * @see PHPMailer::setSMTPInstance() to use a different class.
+     *
+     * @uses \PHPMailer\PHPMailer\SMTP
+     *
+     * @param string $header The message headers
+     * @param string $body   The message body
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    protected function smtpSend($header, $body)
+    {
+        $header = static::stripTrailingWSP($header) . static::$LE . static::$LE;
+        $bad_rcpt = [];
+        if (!$this->smtpConnect($this->SMTPOptions)) {
+            throw new Exception($this->lang('smtp_connect_failed'), self::STOP_CRITICAL);
+        }
+        //Sender already validated in preSend()
+        if ('' === $this->Sender) {
+            $smtp_from = $this->From;
+        } else {
+            $smtp_from = $this->Sender;
+        }
+        if (!$this->smtp->mail($smtp_from)) {
+            $this->setError($this->lang('from_failed') . $smtp_from . ' : ' . implode(',', $this->smtp->getError()));
+            throw new Exception($this->ErrorInfo, self::STOP_CRITICAL);
+        }
+
+        $callbacks = [];
+        //Attempt to send to all recipients
+        foreach ([$this->to, $this->cc, $this->bcc] as $togroup) {
+            foreach ($togroup as $to) {
+                if (!$this->smtp->recipient($to[0], $this->dsn)) {
+                    $error = $this->smtp->getError();
+                    $bad_rcpt[] = ['to' => $to[0], 'error' => $error['detail']];
+                    $isSent = false;
+                } else {
+                    $isSent = true;
+                }
+
+                $callbacks[] = ['issent' => $isSent, 'to' => $to[0], 'name' => $to[1]];
+            }
+        }
+
+        //Only send the DATA command if we have viable recipients
+        if ((count($this->all_recipients) > count($bad_rcpt)) && !$this->smtp->data($header . $body)) {
+            throw new Exception($this->lang('data_not_accepted'), self::STOP_CRITICAL);
+        }
+
+        $smtp_transaction_id = $this->smtp->getLastTransactionID();
+
+        if ($this->SMTPKeepAlive) {
+            $this->smtp->reset();
+        } else {
+            $this->smtp->quit();
+            $this->smtp->close();
+        }
+
+        foreach ($callbacks as $cb) {
+            $this->doCallback(
+                $cb['issent'],
+                [[$cb['to'], $cb['name']]],
+                [],
+                [],
+                $this->Subject,
+                $body,
+                $this->From,
+                ['smtp_transaction_id' => $smtp_transaction_id]
+            );
+        }
+
+        //Create error message for any bad addresses
+        if (count($bad_rcpt) > 0) {
+            $errstr = '';
+            foreach ($bad_rcpt as $bad) {
+                $errstr .= $bad['to'] . ': ' . $bad['error'];
+            }
+            throw new Exception($this->lang('recipients_failed') . $errstr, self::STOP_CONTINUE);
+        }
+
+        return true;
+    }
+
+    /**
+     * Initiate a connection to an SMTP server.
+     * Returns false if the operation failed.
+     *
+     * @param array $options An array of options compatible with stream_context_create()
+     *
+     * @throws Exception
+     *
+     * @uses \PHPMailer\PHPMailer\SMTP
+     *
+     * @return bool
+     */
+    public function smtpConnect($options = null)
+    {
+        if (null === $this->smtp) {
+            $this->smtp = $this->getSMTPInstance();
+        }
+
+        //If no options are provided, use whatever is set in the instance
+        if (null === $options) {
+            $options = $this->SMTPOptions;
+        }
+
+        //Already connected?
+        if ($this->smtp->connected()) {
+            return true;
+        }
+
+        $this->smtp->setTimeout($this->Timeout);
+        $this->smtp->setDebugLevel($this->SMTPDebug);
+        $this->smtp->setDebugOutput($this->Debugoutput);
+        $this->smtp->setVerp($this->do_verp);
+        if ($this->Host === null) {
+            $this->Host = 'localhost';
+        }
+        $hosts = explode(';', $this->Host);
+        $lastexception = null;
+
+        foreach ($hosts as $hostentry) {
+            $hostinfo = [];
+            if (
+                !preg_match(
+                    '/^(?:(ssl|tls):\/\/)?(.+?)(?::(\d+))?$/',
+                    trim($hostentry),
+                    $hostinfo
+                )
+            ) {
+                $this->edebug($this->lang('invalid_hostentry') . ' ' . trim($hostentry));
+                //Not a valid host entry
+                continue;
+            }
+            //$hostinfo[1]: optional ssl or tls prefix
+            //$hostinfo[2]: the hostname
+            //$hostinfo[3]: optional port number
+            //The host string prefix can temporarily override the current setting for SMTPSecure
+            //If it's not specified, the default value is used
+
+            //Check the host name is a valid name or IP address before trying to use it
+            if (!static::isValidHost($hostinfo[2])) {
+                $this->edebug($this->lang('invalid_host') . ' ' . $hostinfo[2]);
+                continue;
+            }
+            $prefix = '';
+            $secure = $this->SMTPSecure;
+            $tls = (static::ENCRYPTION_STARTTLS === $this->SMTPSecure);
+            if ('ssl' === $hostinfo[1] || ('' === $hostinfo[1] && static::ENCRYPTION_SMTPS === $this->SMTPSecure)) {
+                $prefix = 'ssl://';
+                $tls = false; //Can't have SSL and TLS at the same time
+                $secure = static::ENCRYPTION_SMTPS;
+            } elseif ('tls' === $hostinfo[1]) {
+                $tls = true;
+                //TLS doesn't use a prefix
+                $secure = static::ENCRYPTION_STARTTLS;
+            }
+            //Do we need the OpenSSL extension?
+            $sslext = defined('OPENSSL_ALGO_SHA256');
+            if (static::ENCRYPTION_STARTTLS === $secure || static::ENCRYPTION_SMTPS === $secure) {
+                //Check for an OpenSSL constant rather than using extension_loaded, which is sometimes disabled
+                if (!$sslext) {
+                    throw new Exception($this->lang('extension_missing') . 'openssl', self::STOP_CRITICAL);
+                }
+            }
+            $host = $hostinfo[2];
+            $port = $this->Port;
+            if (
+                array_key_exists(3, $hostinfo) &&
+                is_numeric($hostinfo[3]) &&
+                $hostinfo[3] > 0 &&
+                $hostinfo[3] < 65536
+            ) {
+                $port = (int) $hostinfo[3];
+            }
+            if ($this->smtp->connect($prefix . $host, $port, $this->Timeout, $options)) {
+                try {
+                    if ($this->Helo) {
+                        $hello = $this->Helo;
+                    } else {
+                        $hello = $this->serverHostname();
+                    }
+                    $this->smtp->hello($hello);
+                    //Automatically enable TLS encryption if:
+                    //* it's not disabled
+                    //* we have openssl extension
+                    //* we are not already using SSL
+                    //* the server offers STARTTLS
+                    if ($this->SMTPAutoTLS && $sslext && 'ssl' !== $secure && $this->smtp->getServerExt('STARTTLS')) {
+                        $tls = true;
+                    }
+                    if ($tls) {
+                        if (!$this->smtp->startTLS()) {
+                            $message = $this->getSmtpErrorMessage('connect_host');
+                            throw new Exception($message);
+                        }
+                        //We must resend EHLO after TLS negotiation
+                        $this->smtp->hello($hello);
+                    }
+                    if (
+                        $this->SMTPAuth && !$this->smtp->authenticate(
+                            $this->Username,
+                            $this->Password,
+                            $this->AuthType,
+                            $this->oauth
+                        )
+                    ) {
+                        throw new Exception($this->lang('authenticate'));
+                    }
+
+                    return true;
+                } catch (Exception $exc) {
+                    $lastexception = $exc;
+                    $this->edebug($exc->getMessage());
+                    //We must have connected, but then failed TLS or Auth, so close connection nicely
+                    $this->smtp->quit();
+                }
+            }
+        }
+        //If we get here, all connection attempts have failed, so close connection hard
+        $this->smtp->close();
+        //As we've caught all exceptions, just report whatever the last one was
+        if ($this->exceptions && null !== $lastexception) {
+            throw $lastexception;
+        }
+        if ($this->exceptions) {
+            // no exception was thrown, likely $this->smtp->connect() failed
+            $message = $this->getSmtpErrorMessage('connect_host');
+            throw new Exception($message);
+        }
+
+        return false;
+    }
+
+    /**
+     * Close the active SMTP session if one exists.
+     */
+    public function smtpClose()
+    {
+        if ((null !== $this->smtp) && $this->smtp->connected()) {
+            $this->smtp->quit();
+            $this->smtp->close();
+        }
+    }
+
+    /**
+     * Set the language for error messages.
+     * The default language is English.
+     *
+     * @param string $langcode  ISO 639-1 2-character language code (e.g. French is "fr")
+     *                          Optionally, the language code can be enhanced with a 4-character
+     *                          script annotation and/or a 2-character country annotation.
+     * @param string $lang_path Path to the language file directory, with trailing separator (slash)
+     *                          Do not set this from user input!
+     *
+     * @return bool Returns true if the requested language was loaded, false otherwise.
+     */
+    public function setLanguage($langcode = 'en', $lang_path = '')
+    {
+        //Backwards compatibility for renamed language codes
+        $renamed_langcodes = [
+            'br' => 'pt_br',
+            'cz' => 'cs',
+            'dk' => 'da',
+            'no' => 'nb',
+            'se' => 'sv',
+            'rs' => 'sr',
+            'tg' => 'tl',
+            'am' => 'hy',
+        ];
+
+        if (array_key_exists($langcode, $renamed_langcodes)) {
+            $langcode = $renamed_langcodes[$langcode];
+        }
+
+        //Define full set of translatable strings in English
+        $PHPMAILER_LANG = [
+            'authenticate' => 'SMTP Error: Could not authenticate.',
+            'buggy_php' => 'Your version of PHP is affected by a bug that may result in corrupted messages.' .
+                ' To fix it, switch to sending using SMTP, disable the mail.add_x_header option in' .
+                ' your php.ini, switch to MacOS or Linux, or upgrade your PHP to version 7.0.17+ or 7.1.3+.',
+            'connect_host' => 'SMTP Error: Could not connect to SMTP host.',
+            'data_not_accepted' => 'SMTP Error: data not accepted.',
+            'empty_message' => 'Message body empty',
+            'encoding' => 'Unknown encoding: ',
+            'execute' => 'Could not execute: ',
+            'extension_missing' => 'Extension missing: ',
+            'file_access' => 'Could not access file: ',
+            'file_open' => 'File Error: Could not open file: ',
+            'from_failed' => 'The following From address failed: ',
+            'instantiate' => 'Could not instantiate mail function.',
+            'invalid_address' => 'Invalid address: ',
+            'invalid_header' => 'Invalid header name or value',
+            'invalid_hostentry' => 'Invalid hostentry: ',
+            'invalid_host' => 'Invalid host: ',
+            'mailer_not_supported' => ' mailer is not supported.',
+            'provide_address' => 'You must provide at least one recipient email address.',
+            'recipients_failed' => 'SMTP Error: The following recipients failed: ',
+            'signing' => 'Signing Error: ',
+            'smtp_code' => 'SMTP code: ',
+            'smtp_code_ex' => 'Additional SMTP info: ',
+            'smtp_connect_failed' => 'SMTP connect() failed.',
+            'smtp_detail' => 'Detail: ',
+            'smtp_error' => 'SMTP server error: ',
+            'variable_set' => 'Cannot set or reset variable: ',
+        ];
+        if (empty($lang_path)) {
+            //Calculate an absolute path so it can work if CWD is not here
+            $lang_path = dirname(__DIR__) . DIRECTORY_SEPARATOR . 'language' . DIRECTORY_SEPARATOR;
+        }
+
+        //Validate $langcode
+        $foundlang = true;
+        $langcode  = strtolower($langcode);
+        if (
+            !preg_match('/^(?P<lang>[a-z]{2})(?P<script>_[a-z]{4})?(?P<country>_[a-z]{2})?$/', $langcode, $matches)
+            && $langcode !== 'en'
+        ) {
+            $foundlang = false;
+            $langcode = 'en';
+        }
+
+        //There is no English translation file
+        if ('en' !== $langcode) {
+            $langcodes = [];
+            if (!empty($matches['script']) && !empty($matches['country'])) {
+                $langcodes[] = $matches['lang'] . $matches['script'] . $matches['country'];
+            }
+            if (!empty($matches['country'])) {
+                $langcodes[] = $matches['lang'] . $matches['country'];
+            }
+            if (!empty($matches['script'])) {
+                $langcodes[] = $matches['lang'] . $matches['script'];
+            }
+            $langcodes[] = $matches['lang'];
+
+            //Try and find a readable language file for the requested language.
+            $foundFile = false;
+            foreach ($langcodes as $code) {
+                $lang_file = $lang_path . 'phpmailer.lang-' . $code . '.php';
+                if (static::fileIsAccessible($lang_file)) {
+                    $foundFile = true;
+                    break;
+                }
+            }
+
+            if ($foundFile === false) {
+                $foundlang = false;
+            } else {
+                $lines = file($lang_file);
+                foreach ($lines as $line) {
+                    //Translation file lines look like this:
+                    //$PHPMAILER_LANG['authenticate'] = 'SMTP-Fehler: Authentifizierung fehlgeschlagen.';
+                    //These files are parsed as text and not PHP so as to avoid the possibility of code injection
+                    //See https://blog.stevenlevithan.com/archives/match-quoted-string
+                    $matches = [];
+                    if (
+                        preg_match(
+                            '/^\$PHPMAILER_LANG\[\'([a-z\d_]+)\'\]\s*=\s*(["\'])(.+)*?\2;/',
+                            $line,
+                            $matches
+                        ) &&
+                        //Ignore unknown translation keys
+                        array_key_exists($matches[1], $PHPMAILER_LANG)
+                    ) {
+                        //Overwrite language-specific strings so we'll never have missing translation keys.
+                        $PHPMAILER_LANG[$matches[1]] = (string)$matches[3];
+                    }
+                }
+            }
+        }
+        $this->language = $PHPMAILER_LANG;
+
+        return $foundlang; //Returns false if language not found
+    }
+
+    /**
+     * Get the array of strings for the current language.
+     *
+     * @return array
+     */
+    public function getTranslations()
+    {
+        if (empty($this->language)) {
+            $this->setLanguage(); // Set the default language.
+        }
+
+        return $this->language;
+    }
+
+    /**
+     * Create recipient headers.
+     *
+     * @param string $type
+     * @param array  $addr An array of recipients,
+     *                     where each recipient is a 2-element indexed array with element 0 containing an address
+     *                     and element 1 containing a name, like:
+     *                     [['joe@example.com', 'Joe User'], ['zoe@example.com', 'Zoe User']]
+     *
+     * @return string
+     */
+    public function addrAppend($type, $addr)
+    {
+        $addresses = [];
+        foreach ($addr as $address) {
+            $addresses[] = $this->addrFormat($address);
+        }
+
+        return $type . ': ' . implode(', ', $addresses) . static::$LE;
+    }
+
+    /**
+     * Format an address for use in a message header.
+     *
+     * @param array $addr A 2-element indexed array, element 0 containing an address, element 1 containing a name like
+     *                    ['joe@example.com', 'Joe User']
+     *
+     * @return string
+     */
+    public function addrFormat($addr)
+    {
+        if (!isset($addr[1]) || ($addr[1] === '')) { //No name provided
+            return $this->secureHeader($addr[0]);
+        }
+
+        return $this->encodeHeader($this->secureHeader($addr[1]), 'phrase') .
+            ' <' . $this->secureHeader($addr[0]) . '>';
+    }
+
+    /**
+     * Word-wrap message.
+     * For use with mailers that do not automatically perform wrapping
+     * and for quoted-printable encoded messages.
+     * Original written by philippe.
+     *
+     * @param string $message The message to wrap
+     * @param int    $length  The line length to wrap to
+     * @param bool   $qp_mode Whether to run in Quoted-Printable mode
+     *
+     * @return string
+     */
+    public function wrapText($message, $length, $qp_mode = false)
+    {
+        if ($qp_mode) {
+            $soft_break = sprintf(' =%s', static::$LE);
+        } else {
+            $soft_break = static::$LE;
+        }
+        //If utf-8 encoding is used, we will need to make sure we don't
+        //split multibyte characters when we wrap
+        $is_utf8 = static::CHARSET_UTF8 === strtolower($this->CharSet);
+        $lelen = strlen(static::$LE);
+        $crlflen = strlen(static::$LE);
+
+        $message = static::normalizeBreaks($message);
+        //Remove a trailing line break
+        if (substr($message, -$lelen) === static::$LE) {
+            $message = substr($message, 0, -$lelen);
+        }
+
+        //Split message into lines
+        $lines = explode(static::$LE, $message);
+        //Message will be rebuilt in here
+        $message = '';
+        foreach ($lines as $line) {
+            $words = explode(' ', $line);
+            $buf = '';
+            $firstword = true;
+            foreach ($words as $word) {
+                if ($qp_mode && (strlen($word) > $length)) {
+                    $space_left = $length - strlen($buf) - $crlflen;
+                    if (!$firstword) {
+                        if ($space_left > 20) {
+                            $len = $space_left;
+                            if ($is_utf8) {
+                                $len = $this->utf8CharBoundary($word, $len);
+                            } elseif ('=' === substr($word, $len - 1, 1)) {
+                                --$len;
+                            } elseif ('=' === substr($word, $len - 2, 1)) {
+                                $len -= 2;
+                            }
+                            $part = substr($word, 0, $len);
+                            $word = substr($word, $len);
+                            $buf .= ' ' . $part;
+                            $message .= $buf . sprintf('=%s', static::$LE);
+                        } else {
+                            $message .= $buf . $soft_break;
+                        }
+                        $buf = '';
+                    }
+                    while ($word !== '') {
+                        if ($length <= 0) {
+                            break;
+                        }
+                        $len = $length;
+                        if ($is_utf8) {
+                            $len = $this->utf8CharBoundary($word, $len);
+                        } elseif ('=' === substr($word, $len - 1, 1)) {
+                            --$len;
+                        } elseif ('=' === substr($word, $len - 2, 1)) {
+                            $len -= 2;
+                        }
+                        $part = substr($word, 0, $len);
+                        $word = (string) substr($word, $len);
+
+                        if ($word !== '') {
+                            $message .= $part . sprintf('=%s', static::$LE);
+                        } else {
+                            $buf = $part;
+                        }
+                    }
+                } else {
+                    $buf_o = $buf;
+                    if (!$firstword) {
+                        $buf .= ' ';
+                    }
+                    $buf .= $word;
+
+                    if ('' !== $buf_o && strlen($buf) > $length) {
+                        $message .= $buf_o . $soft_break;
+                        $buf = $word;
+                    }
+                }
+                $firstword = false;
+            }
+            $message .= $buf . static::$LE;
+        }
+
+        return $message;
+    }
+
+    /**
+     * Find the last character boundary prior to $maxLength in a utf-8
+     * quoted-printable encoded string.
+     * Original written by Colin Brown.
+     *
+     * @param string $encodedText utf-8 QP text
+     * @param int    $maxLength   Find the last character boundary prior to this length
+     *
+     * @return int
+     */
+    public function utf8CharBoundary($encodedText, $maxLength)
+    {
+        $foundSplitPos = false;
+        $lookBack = 3;
+        while (!$foundSplitPos) {
+            $lastChunk = substr($encodedText, $maxLength - $lookBack, $lookBack);
+            $encodedCharPos = strpos($lastChunk, '=');
+            if (false !== $encodedCharPos) {
+                //Found start of encoded character byte within $lookBack block.
+                //Check the encoded byte value (the 2 chars after the '=')
+                $hex = substr($encodedText, $maxLength - $lookBack + $encodedCharPos + 1, 2);
+                $dec = hexdec($hex);
+                if ($dec < 128) {
+                    //Single byte character.
+                    //If the encoded char was found at pos 0, it will fit
+                    //otherwise reduce maxLength to start of the encoded char
+                    if ($encodedCharPos > 0) {
+                        $maxLength -= $lookBack - $encodedCharPos;
+                    }
+                    $foundSplitPos = true;
+                } elseif ($dec >= 192) {
+                    //First byte of a multi byte character
+                    //Reduce maxLength to split at start of character
+                    $maxLength -= $lookBack - $encodedCharPos;
+                    $foundSplitPos = true;
+                } elseif ($dec < 192) {
+                    //Middle byte of a multi byte character, look further back
+                    $lookBack += 3;
+                }
+            } else {
+                //No encoded character found
+                $foundSplitPos = true;
+            }
+        }
+
+        return $maxLength;
+    }
+
+    /**
+     * Apply word wrapping to the message body.
+     * Wraps the message body to the number of chars set in the WordWrap property.
+     * You should only do this to plain-text bodies as wrapping HTML tags may break them.
+     * This is called automatically by createBody(), so you don't need to call it yourself.
+     */
+    public function setWordWrap()
+    {
+        if ($this->WordWrap < 1) {
+            return;
+        }
+
+        switch ($this->message_type) {
+            case 'alt':
+            case 'alt_inline':
+            case 'alt_attach':
+            case 'alt_inline_attach':
+                $this->AltBody = $this->wrapText($this->AltBody, $this->WordWrap);
+                break;
+            default:
+                $this->Body = $this->wrapText($this->Body, $this->WordWrap);
+                break;
+        }
+    }
+
+    /**
+     * Assemble message headers.
+     *
+     * @return string The assembled headers
+     */
+    public function createHeader()
+    {
+        $result = '';
+
+        $result .= $this->headerLine('Date', '' === $this->MessageDate ? self::rfcDate() : $this->MessageDate);
+
+        //The To header is created automatically by mail(), so needs to be omitted here
+        if ('mail' !== $this->Mailer) {
+            if ($this->SingleTo) {
+                foreach ($this->to as $toaddr) {
+                    $this->SingleToArray[] = $this->addrFormat($toaddr);
+                }
+            } elseif (count($this->to) > 0) {
+                $result .= $this->addrAppend('To', $this->to);
+            } elseif (count($this->cc) === 0) {
+                $result .= $this->headerLine('To', 'undisclosed-recipients:;');
+            }
+        }
+        $result .= $this->addrAppend('From', [[trim($this->From), $this->FromName]]);
+
+        //sendmail and mail() extract Cc from the header before sending
+        if (count($this->cc) > 0) {
+            $result .= $this->addrAppend('Cc', $this->cc);
+        }
+
+        //sendmail and mail() extract Bcc from the header before sending
+        if (
+            (
+                'sendmail' === $this->Mailer || 'qmail' === $this->Mailer || 'mail' === $this->Mailer
+            )
+            && count($this->bcc) > 0
+        ) {
+            $result .= $this->addrAppend('Bcc', $this->bcc);
+        }
+
+        if (count($this->ReplyTo) > 0) {
+            $result .= $this->addrAppend('Reply-To', $this->ReplyTo);
+        }
+
+        //mail() sets the subject itself
+        if ('mail' !== $this->Mailer) {
+            $result .= $this->headerLine('Subject', $this->encodeHeader($this->secureHeader($this->Subject)));
+        }
+
+        //Only allow a custom message ID if it conforms to RFC 5322 section 3.6.4
+        //https://tools.ietf.org/html/rfc5322#section-3.6.4
+        if (
+            '' !== $this->MessageID &&
+            preg_match(
+                '/^<((([a-z\d!#$%&\'*+\/=?^_`{|}~-]+(\.[a-z\d!#$%&\'*+\/=?^_`{|}~-]+)*)' .
+                '|("(([\x01-\x08\x0B\x0C\x0E-\x1F\x7F]|[\x21\x23-\x5B\x5D-\x7E])' .
+                '|(\\[\x01-\x09\x0B\x0C\x0E-\x7F]))*"))@(([a-z\d!#$%&\'*+\/=?^_`{|}~-]+' .
+                '(\.[a-z\d!#$%&\'*+\/=?^_`{|}~-]+)*)|(\[(([\x01-\x08\x0B\x0C\x0E-\x1F\x7F]' .
+                '|[\x21-\x5A\x5E-\x7E])|(\\[\x01-\x09\x0B\x0C\x0E-\x7F]))*\])))>$/Di',
+                $this->MessageID
+            )
+        ) {
+            $this->lastMessageID = $this->MessageID;
+        } else {
+            $this->lastMessageID = sprintf('<%s@%s>', $this->uniqueid, $this->serverHostname());
+        }
+        $result .= $this->headerLine('Message-ID', $this->lastMessageID);
+        if (null !== $this->Priority) {
+            $result .= $this->headerLine('X-Priority', $this->Priority);
+        }
+        if ('' === $this->XMailer) {
+            //Empty string for default X-Mailer header
+            $result .= $this->headerLine(
+                'X-Mailer',
+                'PHPMailer ' . self::VERSION . ' (https://github.com/PHPMailer/PHPMailer)'
+            );
+        } elseif (is_string($this->XMailer) && trim($this->XMailer) !== '') {
+            //Some string
+            $result .= $this->headerLine('X-Mailer', trim($this->XMailer));
+        } //Other values result in no X-Mailer header
+
+        if ('' !== $this->ConfirmReadingTo) {
+            $result .= $this->headerLine('Disposition-Notification-To', '<' . $this->ConfirmReadingTo . '>');
+        }
+
+        //Add custom headers
+        foreach ($this->CustomHeader as $header) {
+            $result .= $this->headerLine(
+                trim($header[0]),
+                $this->encodeHeader(trim($header[1]))
+            );
+        }
+        if (!$this->sign_key_file) {
+            $result .= $this->headerLine('MIME-Version', '1.0');
+            $result .= $this->getMailMIME();
+        }
+
+        return $result;
+    }
+
+    /**
+     * Get the message MIME type headers.
+     *
+     * @return string
+     */
+    public function getMailMIME()
+    {
+        $result = '';
+        $ismultipart = true;
+        switch ($this->message_type) {
+            case 'inline':
+                $result .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_RELATED . ';');
+                $result .= $this->textLine(' boundary="' . $this->boundary[1] . '"');
+                break;
+            case 'attach':
+            case 'inline_attach':
+            case 'alt_attach':
+            case 'alt_inline_attach':
+                $result .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_MIXED . ';');
+                $result .= $this->textLine(' boundary="' . $this->boundary[1] . '"');
+                break;
+            case 'alt':
+            case 'alt_inline':
+                $result .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_ALTERNATIVE . ';');
+                $result .= $this->textLine(' boundary="' . $this->boundary[1] . '"');
+                break;
+            default:
+                //Catches case 'plain': and case '':
+                $result .= $this->textLine('Content-Type: ' . $this->ContentType . '; charset=' . $this->CharSet);
+                $ismultipart = false;
+                break;
+        }
+        //RFC1341 part 5 says 7bit is assumed if not specified
+        if (static::ENCODING_7BIT !== $this->Encoding) {
+            //RFC 2045 section 6.4 says multipart MIME parts may only use 7bit, 8bit or binary CTE
+            if ($ismultipart) {
+                if (static::ENCODING_8BIT === $this->Encoding) {
+                    $result .= $this->headerLine('Content-Transfer-Encoding', static::ENCODING_8BIT);
+                }
+                //The only remaining alternatives are quoted-printable and base64, which are both 7bit compatible
+            } else {
+                $result .= $this->headerLine('Content-Transfer-Encoding', $this->Encoding);
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     * Returns the whole MIME message.
+     * Includes complete headers and body.
+     * Only valid post preSend().
+     *
+     * @see PHPMailer::preSend()
+     *
+     * @return string
+     */
+    public function getSentMIMEMessage()
+    {
+        return static::stripTrailingWSP($this->MIMEHeader . $this->mailHeader) .
+            static::$LE . static::$LE . $this->MIMEBody;
+    }
+
+    /**
+     * Create a unique ID to use for boundaries.
+     *
+     * @return string
+     */
+    protected function generateId()
+    {
+        $len = 32; //32 bytes = 256 bits
+        $bytes = '';
+        if (function_exists('random_bytes')) {
+            try {
+                $bytes = random_bytes($len);
+            } catch (\Exception $e) {
+                //Do nothing
+            }
+        } elseif (function_exists('openssl_random_pseudo_bytes')) {
+            /** @noinspection CryptographicallySecureRandomnessInspection */
+            $bytes = openssl_random_pseudo_bytes($len);
+        }
+        if ($bytes === '') {
+            //We failed to produce a proper random string, so make do.
+            //Use a hash to force the length to the same as the other methods
+            $bytes = hash('sha256', uniqid((string) mt_rand(), true), true);
+        }
+
+        //We don't care about messing up base64 format here, just want a random string
+        return str_replace(['=', '+', '/'], '', base64_encode(hash('sha256', $bytes, true)));
+    }
+
+    /**
+     * Assemble the message body.
+     * Returns an empty string on failure.
+     *
+     * @throws Exception
+     *
+     * @return string The assembled message body
+     */
+    public function createBody()
+    {
+        $body = '';
+        //Create unique IDs and preset boundaries
+        $this->setBoundaries();
+
+        if ($this->sign_key_file) {
+            $body .= $this->getMailMIME() . static::$LE;
+        }
+
+        $this->setWordWrap();
+
+        $bodyEncoding = $this->Encoding;
+        $bodyCharSet = $this->CharSet;
+        //Can we do a 7-bit downgrade?
+        if (static::ENCODING_8BIT === $bodyEncoding && !$this->has8bitChars($this->Body)) {
+            $bodyEncoding = static::ENCODING_7BIT;
+            //All ISO 8859, Windows codepage and UTF-8 charsets are ascii compatible up to 7-bit
+            $bodyCharSet = static::CHARSET_ASCII;
+        }
+        //If lines are too long, and we're not already using an encoding that will shorten them,
+        //change to quoted-printable transfer encoding for the body part only
+        if (static::ENCODING_BASE64 !== $this->Encoding && static::hasLineLongerThanMax($this->Body)) {
+            $bodyEncoding = static::ENCODING_QUOTED_PRINTABLE;
+        }
+
+        $altBodyEncoding = $this->Encoding;
+        $altBodyCharSet = $this->CharSet;
+        //Can we do a 7-bit downgrade?
+        if (static::ENCODING_8BIT === $altBodyEncoding && !$this->has8bitChars($this->AltBody)) {
+            $altBodyEncoding = static::ENCODING_7BIT;
+            //All ISO 8859, Windows codepage and UTF-8 charsets are ascii compatible up to 7-bit
+            $altBodyCharSet = static::CHARSET_ASCII;
+        }
+        //If lines are too long, and we're not already using an encoding that will shorten them,
+        //change to quoted-printable transfer encoding for the alt body part only
+        if (static::ENCODING_BASE64 !== $altBodyEncoding && static::hasLineLongerThanMax($this->AltBody)) {
+            $altBodyEncoding = static::ENCODING_QUOTED_PRINTABLE;
+        }
+        //Use this as a preamble in all multipart message types
+        $mimepre = '';
+        switch ($this->message_type) {
+            case 'inline':
+                $body .= $mimepre;
+                $body .= $this->getBoundary($this->boundary[1], $bodyCharSet, '', $bodyEncoding);
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->attachAll('inline', $this->boundary[1]);
+                break;
+            case 'attach':
+                $body .= $mimepre;
+                $body .= $this->getBoundary($this->boundary[1], $bodyCharSet, '', $bodyEncoding);
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->attachAll('attachment', $this->boundary[1]);
+                break;
+            case 'inline_attach':
+                $body .= $mimepre;
+                $body .= $this->textLine('--' . $this->boundary[1]);
+                $body .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_RELATED . ';');
+                $body .= $this->textLine(' boundary="' . $this->boundary[2] . '";');
+                $body .= $this->textLine(' type="' . static::CONTENT_TYPE_TEXT_HTML . '"');
+                $body .= static::$LE;
+                $body .= $this->getBoundary($this->boundary[2], $bodyCharSet, '', $bodyEncoding);
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->attachAll('inline', $this->boundary[2]);
+                $body .= static::$LE;
+                $body .= $this->attachAll('attachment', $this->boundary[1]);
+                break;
+            case 'alt':
+                $body .= $mimepre;
+                $body .= $this->getBoundary(
+                    $this->boundary[1],
+                    $altBodyCharSet,
+                    static::CONTENT_TYPE_PLAINTEXT,
+                    $altBodyEncoding
+                );
+                $body .= $this->encodeString($this->AltBody, $altBodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->getBoundary(
+                    $this->boundary[1],
+                    $bodyCharSet,
+                    static::CONTENT_TYPE_TEXT_HTML,
+                    $bodyEncoding
+                );
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                if (!empty($this->Ical)) {
+                    $method = static::ICAL_METHOD_REQUEST;
+                    foreach (static::$IcalMethods as $imethod) {
+                        if (stripos($this->Ical, 'METHOD:' . $imethod) !== false) {
+                            $method = $imethod;
+                            break;
+                        }
+                    }
+                    $body .= $this->getBoundary(
+                        $this->boundary[1],
+                        '',
+                        static::CONTENT_TYPE_TEXT_CALENDAR . '; method=' . $method,
+                        ''
+                    );
+                    $body .= $this->encodeString($this->Ical, $this->Encoding);
+                    $body .= static::$LE;
+                }
+                $body .= $this->endBoundary($this->boundary[1]);
+                break;
+            case 'alt_inline':
+                $body .= $mimepre;
+                $body .= $this->getBoundary(
+                    $this->boundary[1],
+                    $altBodyCharSet,
+                    static::CONTENT_TYPE_PLAINTEXT,
+                    $altBodyEncoding
+                );
+                $body .= $this->encodeString($this->AltBody, $altBodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->textLine('--' . $this->boundary[1]);
+                $body .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_RELATED . ';');
+                $body .= $this->textLine(' boundary="' . $this->boundary[2] . '";');
+                $body .= $this->textLine(' type="' . static::CONTENT_TYPE_TEXT_HTML . '"');
+                $body .= static::$LE;
+                $body .= $this->getBoundary(
+                    $this->boundary[2],
+                    $bodyCharSet,
+                    static::CONTENT_TYPE_TEXT_HTML,
+                    $bodyEncoding
+                );
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->attachAll('inline', $this->boundary[2]);
+                $body .= static::$LE;
+                $body .= $this->endBoundary($this->boundary[1]);
+                break;
+            case 'alt_attach':
+                $body .= $mimepre;
+                $body .= $this->textLine('--' . $this->boundary[1]);
+                $body .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_ALTERNATIVE . ';');
+                $body .= $this->textLine(' boundary="' . $this->boundary[2] . '"');
+                $body .= static::$LE;
+                $body .= $this->getBoundary(
+                    $this->boundary[2],
+                    $altBodyCharSet,
+                    static::CONTENT_TYPE_PLAINTEXT,
+                    $altBodyEncoding
+                );
+                $body .= $this->encodeString($this->AltBody, $altBodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->getBoundary(
+                    $this->boundary[2],
+                    $bodyCharSet,
+                    static::CONTENT_TYPE_TEXT_HTML,
+                    $bodyEncoding
+                );
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                if (!empty($this->Ical)) {
+                    $method = static::ICAL_METHOD_REQUEST;
+                    foreach (static::$IcalMethods as $imethod) {
+                        if (stripos($this->Ical, 'METHOD:' . $imethod) !== false) {
+                            $method = $imethod;
+                            break;
+                        }
+                    }
+                    $body .= $this->getBoundary(
+                        $this->boundary[2],
+                        '',
+                        static::CONTENT_TYPE_TEXT_CALENDAR . '; method=' . $method,
+                        ''
+                    );
+                    $body .= $this->encodeString($this->Ical, $this->Encoding);
+                }
+                $body .= $this->endBoundary($this->boundary[2]);
+                $body .= static::$LE;
+                $body .= $this->attachAll('attachment', $this->boundary[1]);
+                break;
+            case 'alt_inline_attach':
+                $body .= $mimepre;
+                $body .= $this->textLine('--' . $this->boundary[1]);
+                $body .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_ALTERNATIVE . ';');
+                $body .= $this->textLine(' boundary="' . $this->boundary[2] . '"');
+                $body .= static::$LE;
+                $body .= $this->getBoundary(
+                    $this->boundary[2],
+                    $altBodyCharSet,
+                    static::CONTENT_TYPE_PLAINTEXT,
+                    $altBodyEncoding
+                );
+                $body .= $this->encodeString($this->AltBody, $altBodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->textLine('--' . $this->boundary[2]);
+                $body .= $this->headerLine('Content-Type', static::CONTENT_TYPE_MULTIPART_RELATED . ';');
+                $body .= $this->textLine(' boundary="' . $this->boundary[3] . '";');
+                $body .= $this->textLine(' type="' . static::CONTENT_TYPE_TEXT_HTML . '"');
+                $body .= static::$LE;
+                $body .= $this->getBoundary(
+                    $this->boundary[3],
+                    $bodyCharSet,
+                    static::CONTENT_TYPE_TEXT_HTML,
+                    $bodyEncoding
+                );
+                $body .= $this->encodeString($this->Body, $bodyEncoding);
+                $body .= static::$LE;
+                $body .= $this->attachAll('inline', $this->boundary[3]);
+                $body .= static::$LE;
+                $body .= $this->endBoundary($this->boundary[2]);
+                $body .= static::$LE;
+                $body .= $this->attachAll('attachment', $this->boundary[1]);
+                break;
+            default:
+                //Catch case 'plain' and case '', applies to simple `text/plain` and `text/html` body content types
+                //Reset the `Encoding` property in case we changed it for line length reasons
+                $this->Encoding = $bodyEncoding;
+                $body .= $this->encodeString($this->Body, $this->Encoding);
+                break;
+        }
+
+        if ($this->isError()) {
+            $body = '';
+            if ($this->exceptions) {
+                throw new Exception($this->lang('empty_message'), self::STOP_CRITICAL);
+            }
+        } elseif ($this->sign_key_file) {
+            try {
+                if (!defined('PKCS7_TEXT')) {
+                    throw new Exception($this->lang('extension_missing') . 'openssl');
+                }
+
+                $file = tempnam(sys_get_temp_dir(), 'srcsign');
+                $signed = tempnam(sys_get_temp_dir(), 'mailsign');
+                file_put_contents($file, $body);
+
+                //Workaround for PHP bug https://bugs.php.net/bug.php?id=69197
+                if (empty($this->sign_extracerts_file)) {
+                    $sign = @openssl_pkcs7_sign(
+                        $file,
+                        $signed,
+                        'file://' . realpath($this->sign_cert_file),
+                        ['file://' . realpath($this->sign_key_file), $this->sign_key_pass],
+                        []
+                    );
+                } else {
+                    $sign = @openssl_pkcs7_sign(
+                        $file,
+                        $signed,
+                        'file://' . realpath($this->sign_cert_file),
+                        ['file://' . realpath($this->sign_key_file), $this->sign_key_pass],
+                        [],
+                        PKCS7_DETACHED,
+                        $this->sign_extracerts_file
+                    );
+                }
+
+                @unlink($file);
+                if ($sign) {
+                    $body = file_get_contents($signed);
+                    @unlink($signed);
+                    //The message returned by openssl contains both headers and body, so need to split them up
+                    $parts = explode("\n\n", $body, 2);
+                    $this->MIMEHeader .= $parts[0] . static::$LE . static::$LE;
+                    $body = $parts[1];
+                } else {
+                    @unlink($signed);
+                    throw new Exception($this->lang('signing') . openssl_error_string());
+                }
+            } catch (Exception $exc) {
+                $body = '';
+                if ($this->exceptions) {
+                    throw $exc;
+                }
+            }
+        }
+
+        return $body;
+    }
+
+    /**
+     * Get the boundaries that this message will use
+     * @return array
+     */
+    public function getBoundaries()
+    {
+        if (empty($this->boundary)) {
+            $this->setBoundaries();
+        }
+        return $this->boundary;
+    }
+
+    /**
+     * Return the start of a message boundary.
+     *
+     * @param string $boundary
+     * @param string $charSet
+     * @param string $contentType
+     * @param string $encoding
+     *
+     * @return string
+     */
+    protected function getBoundary($boundary, $charSet, $contentType, $encoding)
+    {
+        $result = '';
+        if ('' === $charSet) {
+            $charSet = $this->CharSet;
+        }
+        if ('' === $contentType) {
+            $contentType = $this->ContentType;
+        }
+        if ('' === $encoding) {
+            $encoding = $this->Encoding;
+        }
+        $result .= $this->textLine('--' . $boundary);
+        $result .= sprintf('Content-Type: %s; charset=%s', $contentType, $charSet);
+        $result .= static::$LE;
+        //RFC1341 part 5 says 7bit is assumed if not specified
+        if (static::ENCODING_7BIT !== $encoding) {
+            $result .= $this->headerLine('Content-Transfer-Encoding', $encoding);
+        }
+        $result .= static::$LE;
+
+        return $result;
+    }
+
+    /**
+     * Return the end of a message boundary.
+     *
+     * @param string $boundary
+     *
+     * @return string
+     */
+    protected function endBoundary($boundary)
+    {
+        return static::$LE . '--' . $boundary . '--' . static::$LE;
+    }
+
+    /**
+     * Set the message type.
+     * PHPMailer only supports some preset message types, not arbitrary MIME structures.
+     */
+    protected function setMessageType()
+    {
+        $type = [];
+        if ($this->alternativeExists()) {
+            $type[] = 'alt';
+        }
+        if ($this->inlineImageExists()) {
+            $type[] = 'inline';
+        }
+        if ($this->attachmentExists()) {
+            $type[] = 'attach';
+        }
+        $this->message_type = implode('_', $type);
+        if ('' === $this->message_type) {
+            //The 'plain' message_type refers to the message having a single body element, not that it is plain-text
+            $this->message_type = 'plain';
+        }
+    }
+
+    /**
+     * Format a header line.
+     *
+     * @param string     $name
+     * @param string|int $value
+     *
+     * @return string
+     */
+    public function headerLine($name, $value)
+    {
+        return $name . ': ' . $value . static::$LE;
+    }
+
+    /**
+     * Return a formatted mail line.
+     *
+     * @param string $value
+     *
+     * @return string
+     */
+    public function textLine($value)
+    {
+        return $value . static::$LE;
+    }
+
+    /**
+     * Add an attachment from a path on the filesystem.
+     * Never use a user-supplied path to a file!
+     * Returns false if the file could not be found or read.
+     * Explicitly *does not* support passing URLs; PHPMailer is not an HTTP client.
+     * If you need to do that, fetch the resource yourself and pass it in via a local file or string.
+     *
+     * @param string $path        Path to the attachment
+     * @param string $name        Overrides the attachment name
+     * @param string $encoding    File encoding (see $Encoding)
+     * @param string $type        MIME type, e.g. `image/jpeg`; determined automatically from $path if not specified
+     * @param string $disposition Disposition to use
+     *
+     * @throws Exception
+     *
+     * @return bool
+     */
+    public function addAttachment(
+        $path,
+        $name = '',
+        $encoding = self::ENCODING_BASE64,
+        $type = '',
+        $disposition = 'attachment'
+    ) {
+        try {
+            if (!static::fileIsAccessible($path)) {
+                throw new Exception($this->lang('file_access') . $path, self::STOP_CONTINUE);
+            }
+
+            //If a MIME type is not specified, try to work it out from the file name
+            if ('' === $type) {
+                $type = static::filenameToType($path);
+            }
+
+            $filename = (string) static::mb_pathinfo($path, PATHINFO_BASENAME);
+            if ('' === $name) {
+                $name = $filename;
+            }
+            if (!$this->validateEncoding($encoding)) {
+                throw new Exception($this->lang('encoding') . $encoding);
+            }
+
+            $this->attachment[] = [
+                0 => $path,
+                1 => $filename,
+                2 => $name,
+                3 => $encoding,
+                4 => $type,
+                5 => false, //isStringAttachment
+                6 => $disposition,
+                7 => $name,
+            ];
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            $this->edebug($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Return the array of attachments.
+     *
+     * @return array
+     */
+    public function getAttachments()
+    {
+        return $this->attachment;
+    }
+
+    /**
+     * Attach all file, string, and binary attachments to the message.
+     * Returns an empty string on failure.
+     *
+     * @param string $disposition_type
+     * @param string $boundary
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    protected function attachAll($disposition_type, $boundary)
+    {
+        //Return text of body
+        $mime = [];
+        $cidUniq = [];
+        $incl = [];
+
+        //Add all attachments
+        foreach ($this->attachment as $attachment) {
+            //Check if it is a valid disposition_filter
+            if ($attachment[6] === $disposition_type) {
+                //Check for string attachment
+                $string = '';
+                $path = '';
+                $bString = $attachment[5];
+                if ($bString) {
+                    $string = $attachment[0];
+                } else {
+                    $path = $attachment[0];
+                }
+
+                $inclhash = hash('sha256', serialize($attachment));
+                if (in_array($inclhash, $incl, true)) {
+                    continue;
+                }
+                $incl[] = $inclhash;
+                $name = $attachment[2];
+                $encoding = $attachment[3];
+                $type = $attachment[4];
+                $disposition = $attachment[6];
+                $cid = $attachment[7];
+                if ('inline' === $disposition && array_key_exists($cid, $cidUniq)) {
+                    continue;
+                }
+                $cidUniq[$cid] = true;
+
+                $mime[] = sprintf('--%s%s', $boundary, static::$LE);
+                //Only include a filename property if we have one
+                if (!empty($name)) {
+                    $mime[] = sprintf(
+                        'Content-Type: %s; name=%s%s',
+                        $type,
+                        static::quotedString($this->encodeHeader($this->secureHeader($name))),
+                        static::$LE
+                    );
+                } else {
+                    $mime[] = sprintf(
+                        'Content-Type: %s%s',
+                        $type,
+                        static::$LE
+                    );
+                }
+                //RFC1341 part 5 says 7bit is assumed if not specified
+                if (static::ENCODING_7BIT !== $encoding) {
+                    $mime[] = sprintf('Content-Transfer-Encoding: %s%s', $encoding, static::$LE);
+                }
+
+                //Only set Content-IDs on inline attachments
+                if ((string) $cid !== '' && $disposition === 'inline') {
+                    $mime[] = 'Content-ID: <' . $this->encodeHeader($this->secureHeader($cid)) . '>' . static::$LE;
+                }
+
+                //Allow for bypassing the Content-Disposition header
+                if (!empty($disposition)) {
+                    $encoded_name = $this->encodeHeader($this->secureHeader($name));
+                    if (!empty($encoded_name)) {
+                        $mime[] = sprintf(
+                            'Content-Disposition: %s; filename=%s%s',
+                            $disposition,
+                            static::quotedString($encoded_name),
+                            static::$LE . static::$LE
+                        );
+                    } else {
+                        $mime[] = sprintf(
+                            'Content-Disposition: %s%s',
+                            $disposition,
+                            static::$LE . static::$LE
+                        );
+                    }
+                } else {
+                    $mime[] = static::$LE;
+                }
+
+                //Encode as string attachment
+                if ($bString) {
+                    $mime[] = $this->encodeString($string, $encoding);
+                } else {
+                    $mime[] = $this->encodeFile($path, $encoding);
+                }
+                if ($this->isError()) {
+                    return '';
+                }
+                $mime[] = static::$LE;
+            }
+        }
+
+        $mime[] = sprintf('--%s--%s', $boundary, static::$LE);
+
+        return implode('', $mime);
+    }
+
+    /**
+     * Encode a file attachment in requested format.
+     * Returns an empty string on failure.
+     *
+     * @param string $path     The full path to the file
+     * @param string $encoding The encoding to use; one of 'base64', '7bit', '8bit', 'binary', 'quoted-printable'
+     *
+     * @return string
+     */
+    protected function encodeFile($path, $encoding = self::ENCODING_BASE64)
+    {
+        try {
+            if (!static::fileIsAccessible($path)) {
+                throw new Exception($this->lang('file_open') . $path, self::STOP_CONTINUE);
+            }
+            $file_buffer = file_get_contents($path);
+            if (false === $file_buffer) {
+                throw new Exception($this->lang('file_open') . $path, self::STOP_CONTINUE);
+            }
+            $file_buffer = $this->encodeString($file_buffer, $encoding);
+
+            return $file_buffer;
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            $this->edebug($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return '';
+        }
+    }
+
+    /**
+     * Encode a string in requested format.
+     * Returns an empty string on failure.
+     *
+     * @param string $str      The text to encode
+     * @param string $encoding The encoding to use; one of 'base64', '7bit', '8bit', 'binary', 'quoted-printable'
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    public function encodeString($str, $encoding = self::ENCODING_BASE64)
+    {
+        $encoded = '';
+        switch (strtolower($encoding)) {
+            case static::ENCODING_BASE64:
+                $encoded = chunk_split(
+                    base64_encode($str),
+                    static::STD_LINE_LENGTH,
+                    static::$LE
+                );
+                break;
+            case static::ENCODING_7BIT:
+            case static::ENCODING_8BIT:
+                $encoded = static::normalizeBreaks($str);
+                //Make sure it ends with a line break
+                if (substr($encoded, -(strlen(static::$LE))) !== static::$LE) {
+                    $encoded .= static::$LE;
+                }
+                break;
+            case static::ENCODING_BINARY:
+                $encoded = $str;
+                break;
+            case static::ENCODING_QUOTED_PRINTABLE:
+                $encoded = $this->encodeQP($str);
+                break;
+            default:
+                $this->setError($this->lang('encoding') . $encoding);
+                if ($this->exceptions) {
+                    throw new Exception($this->lang('encoding') . $encoding);
+                }
+                break;
+        }
+
+        return $encoded;
+    }
+
+    /**
+     * Encode a header value (not including its label) optimally.
+     * Picks shortest of Q, B, or none. Result includes folding if needed.
+     * See RFC822 definitions for phrase, comment and text positions.
+     *
+     * @param string $str      The header value to encode
+     * @param string $position What context the string will be used in
+     *
+     * @return string
+     */
+    public function encodeHeader($str, $position = 'text')
+    {
+        $matchcount = 0;
+        switch (strtolower($position)) {
+            case 'phrase':
+                if (!preg_match('/[\200-\377]/', $str)) {
+                    //Can't use addslashes as we don't know the value of magic_quotes_sybase
+                    $encoded = addcslashes($str, "\0..\37\177\\\"");
+                    if (($str === $encoded) && !preg_match('/[^A-Za-z0-9!#$%&\'*+\/=?^_`{|}~ -]/', $str)) {
+                        return $encoded;
+                    }
+
+                    return "\"$encoded\"";
+                }
+                $matchcount = preg_match_all('/[^\040\041\043-\133\135-\176]/', $str, $matches);
+                break;
+            /* @noinspection PhpMissingBreakStatementInspection */
+            case 'comment':
+                $matchcount = preg_match_all('/[()"]/', $str, $matches);
+            //fallthrough
+            case 'text':
+            default:
+                $matchcount += preg_match_all('/[\000-\010\013\014\016-\037\177-\377]/', $str, $matches);
+                break;
+        }
+
+        if ($this->has8bitChars($str)) {
+            $charset = $this->CharSet;
+        } else {
+            $charset = static::CHARSET_ASCII;
+        }
+
+        //Q/B encoding adds 8 chars and the charset ("` =?<charset>?[QB]?<content>?=`").
+        $overhead = 8 + strlen($charset);
+
+        if ('mail' === $this->Mailer) {
+            $maxlen = static::MAIL_MAX_LINE_LENGTH - $overhead;
+        } else {
+            $maxlen = static::MAX_LINE_LENGTH - $overhead;
+        }
+
+        //Select the encoding that produces the shortest output and/or prevents corruption.
+        if ($matchcount > strlen($str) / 3) {
+            //More than 1/3 of the content needs encoding, use B-encode.
+            $encoding = 'B';
+        } elseif ($matchcount > 0) {
+            //Less than 1/3 of the content needs encoding, use Q-encode.
+            $encoding = 'Q';
+        } elseif (strlen($str) > $maxlen) {
+            //No encoding needed, but value exceeds max line length, use Q-encode to prevent corruption.
+            $encoding = 'Q';
+        } else {
+            //No reformatting needed
+            $encoding = false;
+        }
+
+        switch ($encoding) {
+            case 'B':
+                if ($this->hasMultiBytes($str)) {
+                    //Use a custom function which correctly encodes and wraps long
+                    //multibyte strings without breaking lines within a character
+                    $encoded = $this->base64EncodeWrapMB($str, "\n");
+                } else {
+                    $encoded = base64_encode($str);
+                    $maxlen -= $maxlen % 4;
+                    $encoded = trim(chunk_split($encoded, $maxlen, "\n"));
+                }
+                $encoded = preg_replace('/^(.*)$/m', ' =?' . $charset . "?$encoding?\\1?=", $encoded);
+                break;
+            case 'Q':
+                $encoded = $this->encodeQ($str, $position);
+                $encoded = $this->wrapText($encoded, $maxlen, true);
+                $encoded = str_replace('=' . static::$LE, "\n", trim($encoded));
+                $encoded = preg_replace('/^(.*)$/m', ' =?' . $charset . "?$encoding?\\1?=", $encoded);
+                break;
+            default:
+                return $str;
+        }
+
+        return trim(static::normalizeBreaks($encoded));
+    }
+
+    /**
+     * Check if a string contains multi-byte characters.
+     *
+     * @param string $str multi-byte text to wrap encode
+     *
+     * @return bool
+     */
+    public function hasMultiBytes($str)
+    {
+        if (function_exists('mb_strlen')) {
+            return strlen($str) > mb_strlen($str, $this->CharSet);
+        }
+
+        //Assume no multibytes (we can't handle without mbstring functions anyway)
+        return false;
+    }
+
+    /**
+     * Does a string contain any 8-bit chars (in any charset)?
+     *
+     * @param string $text
+     *
+     * @return bool
+     */
+    public function has8bitChars($text)
+    {
+        return (bool) preg_match('/[\x80-\xFF]/', $text);
+    }
+
+    /**
+     * Encode and wrap long multibyte strings for mail headers
+     * without breaking lines within a character.
+     * Adapted from a function by paravoid.
+     *
+     * @see http://www.php.net/manual/en/function.mb-encode-mimeheader.php#60283
+     *
+     * @param string $str       multi-byte text to wrap encode
+     * @param string $linebreak string to use as linefeed/end-of-line
+     *
+     * @return string
+     */
+    public function base64EncodeWrapMB($str, $linebreak = null)
+    {
+        $start = '=?' . $this->CharSet . '?B?';
+        $end = '?=';
+        $encoded = '';
+        if (null === $linebreak) {
+            $linebreak = static::$LE;
+        }
+
+        $mb_length = mb_strlen($str, $this->CharSet);
+        //Each line must have length <= 75, including $start and $end
+        $length = 75 - strlen($start) - strlen($end);
+        //Average multi-byte ratio
+        $ratio = $mb_length / strlen($str);
+        //Base64 has a 4:3 ratio
+        $avgLength = floor($length * $ratio * .75);
+
+        $offset = 0;
+        for ($i = 0; $i < $mb_length; $i += $offset) {
+            $lookBack = 0;
+            do {
+                $offset = $avgLength - $lookBack;
+                $chunk = mb_substr($str, $i, $offset, $this->CharSet);
+                $chunk = base64_encode($chunk);
+                ++$lookBack;
+            } while (strlen($chunk) > $length);
+            $encoded .= $chunk . $linebreak;
+        }
+
+        //Chomp the last linefeed
+        return substr($encoded, 0, -strlen($linebreak));
+    }
+
+    /**
+     * Encode a string in quoted-printable format.
+     * According to RFC2045 section 6.7.
+     *
+     * @param string $string The text to encode
+     *
+     * @return string
+     */
+    public function encodeQP($string)
+    {
+        return static::normalizeBreaks(quoted_printable_encode($string));
+    }
+
+    /**
+     * Encode a string using Q encoding.
+     *
+     * @see http://tools.ietf.org/html/rfc2047#section-4.2
+     *
+     * @param string $str      the text to encode
+     * @param string $position Where the text is going to be used, see the RFC for what that means
+     *
+     * @return string
+     */
+    public function encodeQ($str, $position = 'text')
+    {
+        //There should not be any EOL in the string
+        $pattern = '';
+        $encoded = str_replace(["\r", "\n"], '', $str);
+        switch (strtolower($position)) {
+            case 'phrase':
+                //RFC 2047 section 5.3
+                $pattern = '^A-Za-z0-9!*+\/ -';
+                break;
+            /*
+             * RFC 2047 section 5.2.
+             * Build $pattern without including delimiters and []
+             */
+            /* @noinspection PhpMissingBreakStatementInspection */
+            case 'comment':
+                $pattern = '\(\)"';
+            /* Intentional fall through */
+            case 'text':
+            default:
+                //RFC 2047 section 5.1
+                //Replace every high ascii, control, =, ? and _ characters
+                $pattern = '\000-\011\013\014\016-\037\075\077\137\177-\377' . $pattern;
+                break;
+        }
+        $matches = [];
+        if (preg_match_all("/[{$pattern}]/", $encoded, $matches)) {
+            //If the string contains an '=', make sure it's the first thing we replace
+            //so as to avoid double-encoding
+            $eqkey = array_search('=', $matches[0], true);
+            if (false !== $eqkey) {
+                unset($matches[0][$eqkey]);
+                array_unshift($matches[0], '=');
+            }
+            foreach (array_unique($matches[0]) as $char) {
+                $encoded = str_replace($char, '=' . sprintf('%02X', ord($char)), $encoded);
+            }
+        }
+        //Replace spaces with _ (more readable than =20)
+        //RFC 2047 section 4.2(2)
+        return str_replace(' ', '_', $encoded);
+    }
+
+    /**
+     * Add a string or binary attachment (non-filesystem).
+     * This method can be used to attach ascii or binary data,
+     * such as a BLOB record from a database.
+     *
+     * @param string $string      String attachment data
+     * @param string $filename    Name of the attachment
+     * @param string $encoding    File encoding (see $Encoding)
+     * @param string $type        File extension (MIME) type
+     * @param string $disposition Disposition to use
+     *
+     * @throws Exception
+     *
+     * @return bool True on successfully adding an attachment
+     */
+    public function addStringAttachment(
+        $string,
+        $filename,
+        $encoding = self::ENCODING_BASE64,
+        $type = '',
+        $disposition = 'attachment'
+    ) {
+        try {
+            //If a MIME type is not specified, try to work it out from the file name
+            if ('' === $type) {
+                $type = static::filenameToType($filename);
+            }
+
+            if (!$this->validateEncoding($encoding)) {
+                throw new Exception($this->lang('encoding') . $encoding);
+            }
+
+            //Append to $attachment array
+            $this->attachment[] = [
+                0 => $string,
+                1 => $filename,
+                2 => static::mb_pathinfo($filename, PATHINFO_BASENAME),
+                3 => $encoding,
+                4 => $type,
+                5 => true, //isStringAttachment
+                6 => $disposition,
+                7 => 0,
+            ];
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            $this->edebug($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Add an embedded (inline) attachment from a file.
+     * This can include images, sounds, and just about any other document type.
+     * These differ from 'regular' attachments in that they are intended to be
+     * displayed inline with the message, not just attached for download.
+     * This is used in HTML messages that embed the images
+     * the HTML refers to using the `$cid` value in `img` tags, for example `<img src="cid:mylogo">`.
+     * Never use a user-supplied path to a file!
+     *
+     * @param string $path        Path to the attachment
+     * @param string $cid         Content ID of the attachment; Use this to reference
+     *                            the content when using an embedded image in HTML
+     * @param string $name        Overrides the attachment filename
+     * @param string $encoding    File encoding (see $Encoding) defaults to `base64`
+     * @param string $type        File MIME type (by default mapped from the `$path` filename's extension)
+     * @param string $disposition Disposition to use: `inline` (default) or `attachment`
+     *                            (unlikely you want this – {@see `addAttachment()`} instead)
+     *
+     * @return bool True on successfully adding an attachment
+     * @throws Exception
+     *
+     */
+    public function addEmbeddedImage(
+        $path,
+        $cid,
+        $name = '',
+        $encoding = self::ENCODING_BASE64,
+        $type = '',
+        $disposition = 'inline'
+    ) {
+        try {
+            if (!static::fileIsAccessible($path)) {
+                throw new Exception($this->lang('file_access') . $path, self::STOP_CONTINUE);
+            }
+
+            //If a MIME type is not specified, try to work it out from the file name
+            if ('' === $type) {
+                $type = static::filenameToType($path);
+            }
+
+            if (!$this->validateEncoding($encoding)) {
+                throw new Exception($this->lang('encoding') . $encoding);
+            }
+
+            $filename = (string) static::mb_pathinfo($path, PATHINFO_BASENAME);
+            if ('' === $name) {
+                $name = $filename;
+            }
+
+            //Append to $attachment array
+            $this->attachment[] = [
+                0 => $path,
+                1 => $filename,
+                2 => $name,
+                3 => $encoding,
+                4 => $type,
+                5 => false, //isStringAttachment
+                6 => $disposition,
+                7 => $cid,
+            ];
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            $this->edebug($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Add an embedded stringified attachment.
+     * This can include images, sounds, and just about any other document type.
+     * If your filename doesn't contain an extension, be sure to set the $type to an appropriate MIME type.
+     *
+     * @param string $string      The attachment binary data
+     * @param string $cid         Content ID of the attachment; Use this to reference
+     *                            the content when using an embedded image in HTML
+     * @param string $name        A filename for the attachment. If this contains an extension,
+     *                            PHPMailer will attempt to set a MIME type for the attachment.
+     *                            For example 'file.jpg' would get an 'image/jpeg' MIME type.
+     * @param string $encoding    File encoding (see $Encoding), defaults to 'base64'
+     * @param string $type        MIME type - will be used in preference to any automatically derived type
+     * @param string $disposition Disposition to use
+     *
+     * @throws Exception
+     *
+     * @return bool True on successfully adding an attachment
+     */
+    public function addStringEmbeddedImage(
+        $string,
+        $cid,
+        $name = '',
+        $encoding = self::ENCODING_BASE64,
+        $type = '',
+        $disposition = 'inline'
+    ) {
+        try {
+            //If a MIME type is not specified, try to work it out from the name
+            if ('' === $type && !empty($name)) {
+                $type = static::filenameToType($name);
+            }
+
+            if (!$this->validateEncoding($encoding)) {
+                throw new Exception($this->lang('encoding') . $encoding);
+            }
+
+            //Append to $attachment array
+            $this->attachment[] = [
+                0 => $string,
+                1 => $name,
+                2 => $name,
+                3 => $encoding,
+                4 => $type,
+                5 => true, //isStringAttachment
+                6 => $disposition,
+                7 => $cid,
+            ];
+        } catch (Exception $exc) {
+            $this->setError($exc->getMessage());
+            $this->edebug($exc->getMessage());
+            if ($this->exceptions) {
+                throw $exc;
+            }
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Validate encodings.
+     *
+     * @param string $encoding
+     *
+     * @return bool
+     */
+    protected function validateEncoding($encoding)
+    {
+        return in_array(
+            $encoding,
+            [
+                self::ENCODING_7BIT,
+                self::ENCODING_QUOTED_PRINTABLE,
+                self::ENCODING_BASE64,
+                self::ENCODING_8BIT,
+                self::ENCODING_BINARY,
+            ],
+            true
+        );
+    }
+
+    /**
+     * Check if an embedded attachment is present with this cid.
+     *
+     * @param string $cid
+     *
+     * @return bool
+     */
+    protected function cidExists($cid)
+    {
+        foreach ($this->attachment as $attachment) {
+            if ('inline' === $attachment[6] && $cid === $attachment[7]) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Check if an inline attachment is present.
+     *
+     * @return bool
+     */
+    public function inlineImageExists()
+    {
+        foreach ($this->attachment as $attachment) {
+            if ('inline' === $attachment[6]) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Check if an attachment (non-inline) is present.
+     *
+     * @return bool
+     */
+    public function attachmentExists()
+    {
+        foreach ($this->attachment as $attachment) {
+            if ('attachment' === $attachment[6]) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Check if this message has an alternative body set.
+     *
+     * @return bool
+     */
+    public function alternativeExists()
+    {
+        return !empty($this->AltBody);
+    }
+
+    /**
+     * Clear queued addresses of given kind.
+     *
+     * @param string $kind 'to', 'cc', or 'bcc'
+     */
+    public function clearQueuedAddresses($kind)
+    {
+        $this->RecipientsQueue = array_filter(
+            $this->RecipientsQueue,
+            static function ($params) use ($kind) {
+                return $params[0] !== $kind;
+            }
+        );
+    }
+
+    /**
+     * Clear all To recipients.
+     */
+    public function clearAddresses()
+    {
+        foreach ($this->to as $to) {
+            unset($this->all_recipients[strtolower($to[0])]);
+        }
+        $this->to = [];
+        $this->clearQueuedAddresses('to');
+    }
+
+    /**
+     * Clear all CC recipients.
+     */
+    public function clearCCs()
+    {
+        foreach ($this->cc as $cc) {
+            unset($this->all_recipients[strtolower($cc[0])]);
+        }
+        $this->cc = [];
+        $this->clearQueuedAddresses('cc');
+    }
+
+    /**
+     * Clear all BCC recipients.
+     */
+    public function clearBCCs()
+    {
+        foreach ($this->bcc as $bcc) {
+            unset($this->all_recipients[strtolower($bcc[0])]);
+        }
+        $this->bcc = [];
+        $this->clearQueuedAddresses('bcc');
+    }
+
+    /**
+     * Clear all ReplyTo recipients.
+     */
+    public function clearReplyTos()
+    {
+        $this->ReplyTo = [];
+        $this->ReplyToQueue = [];
+    }
+
+    /**
+     * Clear all recipient types.
+     */
+    public function clearAllRecipients()
+    {
+        $this->to = [];
+        $this->cc = [];
+        $this->bcc = [];
+        $this->all_recipients = [];
+        $this->RecipientsQueue = [];
+    }
+
+    /**
+     * Clear all filesystem, string, and binary attachments.
+     */
+    public function clearAttachments()
+    {
+        $this->attachment = [];
+    }
+
+    /**
+     * Clear all custom headers.
+     */
+    public function clearCustomHeaders()
+    {
+        $this->CustomHeader = [];
+    }
+
+    /**
+     * Add an error message to the error container.
+     *
+     * @param string $msg
+     */
+    protected function setError($msg)
+    {
+        ++$this->error_count;
+        if ('smtp' === $this->Mailer && null !== $this->smtp) {
+            $lasterror = $this->smtp->getError();
+            if (!empty($lasterror['error'])) {
+                $msg .= $this->lang('smtp_error') . $lasterror['error'];
+                if (!empty($lasterror['detail'])) {
+                    $msg .= ' ' . $this->lang('smtp_detail') . $lasterror['detail'];
+                }
+                if (!empty($lasterror['smtp_code'])) {
+                    $msg .= ' ' . $this->lang('smtp_code') . $lasterror['smtp_code'];
+                }
+                if (!empty($lasterror['smtp_code_ex'])) {
+                    $msg .= ' ' . $this->lang('smtp_code_ex') . $lasterror['smtp_code_ex'];
+                }
+            }
+        }
+        $this->ErrorInfo = $msg;
+    }
+
+    /**
+     * Return an RFC 822 formatted date.
+     *
+     * @return string
+     */
+    public static function rfcDate()
+    {
+        //Set the time zone to whatever the default is to avoid 500 errors
+        //Will default to UTC if it's not set properly in php.ini
+        date_default_timezone_set(@date_default_timezone_get());
+
+        return date('D, j M Y H:i:s O');
+    }
+
+    /**
+     * Get the server hostname.
+     * Returns 'localhost.localdomain' if unknown.
+     *
+     * @return string
+     */
+    protected function serverHostname()
+    {
+        $result = '';
+        if (!empty($this->Hostname)) {
+            $result = $this->Hostname;
+        } elseif (isset($_SERVER) && array_key_exists('SERVER_NAME', $_SERVER)) {
+            $result = $_SERVER['SERVER_NAME'];
+        } elseif (function_exists('gethostname') && gethostname() !== false) {
+            $result = gethostname();
+        } elseif (php_uname('n') !== false) {
+            $result = php_uname('n');
+        }
+        if (!static::isValidHost($result)) {
+            return 'localhost.localdomain';
+        }
+
+        return $result;
+    }
+
+    /**
+     * Validate whether a string contains a valid value to use as a hostname or IP address.
+     * IPv6 addresses must include [], e.g. `[::1]`, not just `::1`.
+     *
+     * @param string $host The host name or IP address to check
+     *
+     * @return bool
+     */
+    public static function isValidHost($host)
+    {
+        //Simple syntax limits
+        if (
+            empty($host)
+            || !is_string($host)
+            || strlen($host) > 256
+            || !preg_match('/^([a-zA-Z\d.-]*|\[[a-fA-F\d:]+\])$/', $host)
+        ) {
+            return false;
+        }
+        //Looks like a bracketed IPv6 address
+        if (strlen($host) > 2 && substr($host, 0, 1) === '[' && substr($host, -1, 1) === ']') {
+            return filter_var(substr($host, 1, -1), FILTER_VALIDATE_IP, FILTER_FLAG_IPV6) !== false;
+        }
+        //If removing all the dots results in a numeric string, it must be an IPv4 address.
+        //Need to check this first because otherwise things like `999.0.0.0` are considered valid host names
+        if (is_numeric(str_replace('.', '', $host))) {
+            //Is it a valid IPv4 address?
+            return filter_var($host, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) !== false;
+        }
+        //Is it a syntactically valid hostname (when embeded in a URL)?
+        return filter_var('http://' . $host, FILTER_VALIDATE_URL) !== false;
+    }
+
+    /**
+     * Get an error message in the current language.
+     *
+     * @param string $key
+     *
+     * @return string
+     */
+    protected function lang($key)
+    {
+        if (count($this->language) < 1) {
+            $this->setLanguage(); //Set the default language
+        }
+
+        if (array_key_exists($key, $this->language)) {
+            if ('smtp_connect_failed' === $key) {
+                //Include a link to troubleshooting docs on SMTP connection failure.
+                //This is by far the biggest cause of support questions
+                //but it's usually not PHPMailer's fault.
+                return $this->language[$key] . ' https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting';
+            }
+
+            return $this->language[$key];
+        }
+
+        //Return the key as a fallback
+        return $key;
+    }
+
+    /**
+     * Build an error message starting with a generic one and adding details if possible.
+     *
+     * @param string $base_key
+     * @return string
+     */
+    private function getSmtpErrorMessage($base_key)
+    {
+        $message = $this->lang($base_key);
+        $error = $this->smtp->getError();
+        if (!empty($error['error'])) {
+            $message .= ' ' . $error['error'];
+            if (!empty($error['detail'])) {
+                $message .= ' ' . $error['detail'];
+            }
+        }
+
+        return $message;
+    }
+
+    /**
+     * Check if an error occurred.
+     *
+     * @return bool True if an error did occur
+     */
+    public function isError()
+    {
+        return $this->error_count > 0;
+    }
+
+    /**
+     * Add a custom header.
+     * $name value can be overloaded to contain
+     * both header name and value (name:value).
+     *
+     * @param string      $name  Custom header name
+     * @param string|null $value Header value
+     *
+     * @return bool True if a header was set successfully
+     * @throws Exception
+     */
+    public function addCustomHeader($name, $value = null)
+    {
+        if (null === $value && strpos($name, ':') !== false) {
+            //Value passed in as name:value
+            list($name, $value) = explode(':', $name, 2);
+        }
+        $name = trim($name);
+        $value = (null === $value) ? '' : trim($value);
+        //Ensure name is not empty, and that neither name nor value contain line breaks
+        if (empty($name) || strpbrk($name . $value, "\r\n") !== false) {
+            if ($this->exceptions) {
+                throw new Exception($this->lang('invalid_header'));
+            }
+
+            return false;
+        }
+        $this->CustomHeader[] = [$name, $value];
+
+        return true;
+    }
+
+    /**
+     * Returns all custom headers.
+     *
+     * @return array
+     */
+    public function getCustomHeaders()
+    {
+        return $this->CustomHeader;
+    }
+
+    /**
+     * Create a message body from an HTML string.
+     * Automatically inlines images and creates a plain-text version by converting the HTML,
+     * overwriting any existing values in Body and AltBody.
+     * Do not source $message content from user input!
+     * $basedir is prepended when handling relative URLs, e.g. <img src="/images/a.png"> and must not be empty
+     * will look for an image file in $basedir/images/a.png and convert it to inline.
+     * If you don't provide a $basedir, relative paths will be left untouched (and thus probably break in email)
+     * Converts data-uri images into embedded attachments.
+     * If you don't want to apply these transformations to your HTML, just set Body and AltBody directly.
+     *
+     * @param string        $message  HTML message string
+     * @param string        $basedir  Absolute path to a base directory to prepend to relative paths to images
+     * @param bool|callable $advanced Whether to use the internal HTML to text converter
+     *                                or your own custom converter
+     * @return string The transformed message body
+     *
+     * @throws Exception
+     *
+     * @see PHPMailer::html2text()
+     */
+    public function msgHTML($message, $basedir = '', $advanced = false)
+    {
+        preg_match_all('/(?<!-)(src|background)=["\'](.*)["\']/Ui', $message, $images);
+        if (array_key_exists(2, $images)) {
+            if (strlen($basedir) > 1 && '/' !== substr($basedir, -1)) {
+                //Ensure $basedir has a trailing /
+                $basedir .= '/';
+            }
+            foreach ($images[2] as $imgindex => $url) {
+                //Convert data URIs into embedded images
+                //e.g. "data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw=="
+                $match = [];
+                if (preg_match('#^data:(image/(?:jpe?g|gif|png));?(base64)?,(.+)#', $url, $match)) {
+                    if (count($match) === 4 && static::ENCODING_BASE64 === $match[2]) {
+                        $data = base64_decode($match[3]);
+                    } elseif ('' === $match[2]) {
+                        $data = rawurldecode($match[3]);
+                    } else {
+                        //Not recognised so leave it alone
+                        continue;
+                    }
+                    //Hash the decoded data, not the URL, so that the same data-URI image used in multiple places
+                    //will only be embedded once, even if it used a different encoding
+                    $cid = substr(hash('sha256', $data), 0, 32) . '@phpmailer.0'; //RFC2392 S 2
+
+                    if (!$this->cidExists($cid)) {
+                        $this->addStringEmbeddedImage(
+                            $data,
+                            $cid,
+                            'embed' . $imgindex,
+                            static::ENCODING_BASE64,
+                            $match[1]
+                        );
+                    }
+                    $message = str_replace(
+                        $images[0][$imgindex],
+                        $images[1][$imgindex] . '="cid:' . $cid . '"',
+                        $message
+                    );
+                    continue;
+                }
+                if (
+                    //Only process relative URLs if a basedir is provided (i.e. no absolute local paths)
+                    !empty($basedir)
+                    //Ignore URLs containing parent dir traversal (..)
+                    && (strpos($url, '..') === false)
+                    //Do not change urls that are already inline images
+                    && 0 !== strpos($url, 'cid:')
+                    //Do not change absolute URLs, including anonymous protocol
+                    && !preg_match('#^[a-z][a-z0-9+.-]*:?//#i', $url)
+                ) {
+                    $filename = static::mb_pathinfo($url, PATHINFO_BASENAME);
+                    $directory = dirname($url);
+                    if ('.' === $directory) {
+                        $directory = '';
+                    }
+                    //RFC2392 S 2
+                    $cid = substr(hash('sha256', $url), 0, 32) . '@phpmailer.0';
+                    if (strlen($basedir) > 1 && '/' !== substr($basedir, -1)) {
+                        $basedir .= '/';
+                    }
+                    if (strlen($directory) > 1 && '/' !== substr($directory, -1)) {
+                        $directory .= '/';
+                    }
+                    if (
+                        $this->addEmbeddedImage(
+                            $basedir . $directory . $filename,
+                            $cid,
+                            $filename,
+                            static::ENCODING_BASE64,
+                            static::_mime_types((string) static::mb_pathinfo($filename, PATHINFO_EXTENSION))
+                        )
+                    ) {
+                        $message = preg_replace(
+                            '/' . $images[1][$imgindex] . '=["\']' . preg_quote($url, '/') . '["\']/Ui',
+                            $images[1][$imgindex] . '="cid:' . $cid . '"',
+                            $message
+                        );
+                    }
+                }
+            }
+        }
+        $this->isHTML();
+        //Convert all message body line breaks to LE, makes quoted-printable encoding work much better
+        $this->Body = static::normalizeBreaks($message);
+        $this->AltBody = static::normalizeBreaks($this->html2text($message, $advanced));
+        if (!$this->alternativeExists()) {
+            $this->AltBody = 'This is an HTML-only message. To view it, activate HTML in your email application.'
+                . static::$LE;
+        }
+
+        return $this->Body;
+    }
+
+    /**
+     * Convert an HTML string into plain text.
+     * This is used by msgHTML().
+     * Note - older versions of this function used a bundled advanced converter
+     * which was removed for license reasons in #232.
+     * Example usage:
+     *
+     * ```php
+     * //Use default conversion
+     * $plain = $mail->html2text($html);
+     * //Use your own custom converter
+     * $plain = $mail->html2text($html, function($html) {
+     *     $converter = new MyHtml2text($html);
+     *     return $converter->get_text();
+     * });
+     * ```
+     *
+     * @param string        $html     The HTML text to convert
+     * @param bool|callable $advanced Any boolean value to use the internal converter,
+     *                                or provide your own callable for custom conversion.
+     *                                *Never* pass user-supplied data into this parameter
+     *
+     * @return string
+     */
+    public function html2text($html, $advanced = false)
+    {
+        if (is_callable($advanced)) {
+            return call_user_func($advanced, $html);
+        }
+
+        return html_entity_decode(
+            trim(strip_tags(preg_replace('/<(head|title|style|script)[^>]*>.*?<\/\\1>/si', '', $html))),
+            ENT_QUOTES,
+            $this->CharSet
+        );
+    }
+
+    /**
+     * Get the MIME type for a file extension.
+     *
+     * @param string $ext File extension
+     *
+     * @return string MIME type of file
+     */
+    public static function _mime_types($ext = '')
+    {
+        $mimes = [
+            'xl' => 'application/excel',
+            'js' => 'application/javascript',
+            'hqx' => 'application/mac-binhex40',
+            'cpt' => 'application/mac-compactpro',
+            'bin' => 'application/macbinary',
+            'doc' => 'application/msword',
+            'word' => 'application/msword',
+            'xlsx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
+            'xltx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
+            'potx' => 'application/vnd.openxmlformats-officedocument.presentationml.template',
+            'ppsx' => 'application/vnd.openxmlformats-officedocument.presentationml.slideshow',
+            'pptx' => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
+            'sldx' => 'application/vnd.openxmlformats-officedocument.presentationml.slide',
+            'docx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
+            'dotx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
+            'xlam' => 'application/vnd.ms-excel.addin.macroEnabled.12',
+            'xlsb' => 'application/vnd.ms-excel.sheet.binary.macroEnabled.12',
+            'class' => 'application/octet-stream',
+            'dll' => 'application/octet-stream',
+            'dms' => 'application/octet-stream',
+            'exe' => 'application/octet-stream',
+            'lha' => 'application/octet-stream',
+            'lzh' => 'application/octet-stream',
+            'psd' => 'application/octet-stream',
+            'sea' => 'application/octet-stream',
+            'so' => 'application/octet-stream',
+            'oda' => 'application/oda',
+            'pdf' => 'application/pdf',
+            'ai' => 'application/postscript',
+            'eps' => 'application/postscript',
+            'ps' => 'application/postscript',
+            'smi' => 'application/smil',
+            'smil' => 'application/smil',
+            'mif' => 'application/vnd.mif',
+            'xls' => 'application/vnd.ms-excel',
+            'ppt' => 'application/vnd.ms-powerpoint',
+            'wbxml' => 'application/vnd.wap.wbxml',
+            'wmlc' => 'application/vnd.wap.wmlc',
+            'dcr' => 'application/x-director',
+            'dir' => 'application/x-director',
+            'dxr' => 'application/x-director',
+            'dvi' => 'application/x-dvi',
+            'gtar' => 'application/x-gtar',
+            'php3' => 'application/x-httpd-php',
+            'php4' => 'application/x-httpd-php',
+            'php' => 'application/x-httpd-php',
+            'phtml' => 'application/x-httpd-php',
+            'phps' => 'application/x-httpd-php-source',
+            'swf' => 'application/x-shockwave-flash',
+            'sit' => 'application/x-stuffit',
+            'tar' => 'application/x-tar',
+            'tgz' => 'application/x-tar',
+            'xht' => 'application/xhtml+xml',
+            'xhtml' => 'application/xhtml+xml',
+            'zip' => 'application/zip',
+            'mid' => 'audio/midi',
+            'midi' => 'audio/midi',
+            'mp2' => 'audio/mpeg',
+            'mp3' => 'audio/mpeg',
+            'm4a' => 'audio/mp4',
+            'mpga' => 'audio/mpeg',
+            'aif' => 'audio/x-aiff',
+            'aifc' => 'audio/x-aiff',
+            'aiff' => 'audio/x-aiff',
+            'ram' => 'audio/x-pn-realaudio',
+            'rm' => 'audio/x-pn-realaudio',
+            'rpm' => 'audio/x-pn-realaudio-plugin',
+            'ra' => 'audio/x-realaudio',
+            'wav' => 'audio/x-wav',
+            'mka' => 'audio/x-matroska',
+            'bmp' => 'image/bmp',
+            'gif' => 'image/gif',
+            'jpeg' => 'image/jpeg',
+            'jpe' => 'image/jpeg',
+            'jpg' => 'image/jpeg',
+            'png' => 'image/png',
+            'tiff' => 'image/tiff',
+            'tif' => 'image/tiff',
+            'webp' => 'image/webp',
+            'avif' => 'image/avif',
+            'heif' => 'image/heif',
+            'heifs' => 'image/heif-sequence',
+            'heic' => 'image/heic',
+            'heics' => 'image/heic-sequence',
+            'eml' => 'message/rfc822',
+            'css' => 'text/css',
+            'html' => 'text/html',
+            'htm' => 'text/html',
+            'shtml' => 'text/html',
+            'log' => 'text/plain',
+            'text' => 'text/plain',
+            'txt' => 'text/plain',
+            'rtx' => 'text/richtext',
+            'rtf' => 'text/rtf',
+            'vcf' => 'text/vcard',
+            'vcard' => 'text/vcard',
+            'ics' => 'text/calendar',
+            'xml' => 'text/xml',
+            'xsl' => 'text/xml',
+            'csv' => 'text/csv',
+            'wmv' => 'video/x-ms-wmv',
+            'mpeg' => 'video/mpeg',
+            'mpe' => 'video/mpeg',
+            'mpg' => 'video/mpeg',
+            'mp4' => 'video/mp4',
+            'm4v' => 'video/mp4',
+            'mov' => 'video/quicktime',
+            'qt' => 'video/quicktime',
+            'rv' => 'video/vnd.rn-realvideo',
+            'avi' => 'video/x-msvideo',
+            'movie' => 'video/x-sgi-movie',
+            'webm' => 'video/webm',
+            'mkv' => 'video/x-matroska',
+        ];
+        $ext = strtolower($ext);
+        if (array_key_exists($ext, $mimes)) {
+            return $mimes[$ext];
+        }
+
+        return 'application/octet-stream';
+    }
+
+    /**
+     * Map a file name to a MIME type.
+     * Defaults to 'application/octet-stream', i.e.. arbitrary binary data.
+     *
+     * @param string $filename A file name or full path, does not need to exist as a file
+     *
+     * @return string
+     */
+    public static function filenameToType($filename)
+    {
+        //In case the path is a URL, strip any query string before getting extension
+        $qpos = strpos($filename, '?');
+        if (false !== $qpos) {
+            $filename = substr($filename, 0, $qpos);
+        }
+        $ext = static::mb_pathinfo($filename, PATHINFO_EXTENSION);
+
+        return static::_mime_types($ext);
+    }
+
+    /**
+     * Multi-byte-safe pathinfo replacement.
+     * Drop-in replacement for pathinfo(), but multibyte- and cross-platform-safe.
+     *
+     * @see http://www.php.net/manual/en/function.pathinfo.php#107461
+     *
+     * @param string     $path    A filename or path, does not need to exist as a file
+     * @param int|string $options Either a PATHINFO_* constant,
+     *                            or a string name to return only the specified piece
+     *
+     * @return string|array
+     */
+    public static function mb_pathinfo($path, $options = null)
+    {
+        $ret = ['dirname' => '', 'basename' => '', 'extension' => '', 'filename' => ''];
+        $pathinfo = [];
+        if (preg_match('#^(.*?)[\\\\/]*(([^/\\\\]*?)(\.([^.\\\\/]+?)|))[\\\\/.]*$#m', $path, $pathinfo)) {
+            if (array_key_exists(1, $pathinfo)) {
+                $ret['dirname'] = $pathinfo[1];
+            }
+            if (array_key_exists(2, $pathinfo)) {
+                $ret['basename'] = $pathinfo[2];
+            }
+            if (array_key_exists(5, $pathinfo)) {
+                $ret['extension'] = $pathinfo[5];
+            }
+            if (array_key_exists(3, $pathinfo)) {
+                $ret['filename'] = $pathinfo[3];
+            }
+        }
+        switch ($options) {
+            case PATHINFO_DIRNAME:
+            case 'dirname':
+                return $ret['dirname'];
+            case PATHINFO_BASENAME:
+            case 'basename':
+                return $ret['basename'];
+            case PATHINFO_EXTENSION:
+            case 'extension':
+                return $ret['extension'];
+            case PATHINFO_FILENAME:
+            case 'filename':
+                return $ret['filename'];
+            default:
+                return $ret;
+        }
+    }
+
+    /**
+     * Set or reset instance properties.
+     * You should avoid this function - it's more verbose, less efficient, more error-prone and
+     * harder to debug than setting properties directly.
+     * Usage Example:
+     * `$mail->set('SMTPSecure', static::ENCRYPTION_STARTTLS);`
+     *   is the same as:
+     * `$mail->SMTPSecure = static::ENCRYPTION_STARTTLS;`.
+     *
+     * @param string $name  The property name to set
+     * @param mixed  $value The value to set the property to
+     *
+     * @return bool
+     */
+    public function set($name, $value = '')
+    {
+        if (property_exists($this, $name)) {
+            $this->{$name} = $value;
+
+            return true;
+        }
+        $this->setError($this->lang('variable_set') . $name);
+
+        return false;
+    }
+
+    /**
+     * Strip newlines to prevent header injection.
+     *
+     * @param string $str
+     *
+     * @return string
+     */
+    public function secureHeader($str)
+    {
+        return trim(str_replace(["\r", "\n"], '', $str));
+    }
+
+    /**
+     * Normalize line breaks in a string.
+     * Converts UNIX LF, Mac CR and Windows CRLF line breaks into a single line break format.
+     * Defaults to CRLF (for message bodies) and preserves consecutive breaks.
+     *
+     * @param string $text
+     * @param string $breaktype What kind of line break to use; defaults to static::$LE
+     *
+     * @return string
+     */
+    public static function normalizeBreaks($text, $breaktype = null)
+    {
+        if (null === $breaktype) {
+            $breaktype = static::$LE;
+        }
+        //Normalise to \n
+        $text = str_replace([self::CRLF, "\r"], "\n", $text);
+        //Now convert LE as needed
+        if ("\n" !== $breaktype) {
+            $text = str_replace("\n", $breaktype, $text);
+        }
+
+        return $text;
+    }
+
+    /**
+     * Remove trailing whitespace from a string.
+     *
+     * @param string $text
+     *
+     * @return string The text to remove whitespace from
+     */
+    public static function stripTrailingWSP($text)
+    {
+        return rtrim($text, " \r\n\t");
+    }
+
+    /**
+     * Strip trailing line breaks from a string.
+     *
+     * @param string $text
+     *
+     * @return string The text to remove breaks from
+     */
+    public static function stripTrailingBreaks($text)
+    {
+        return rtrim($text, "\r\n");
+    }
+
+    /**
+     * Return the current line break format string.
+     *
+     * @return string
+     */
+    public static function getLE()
+    {
+        return static::$LE;
+    }
+
+    /**
+     * Set the line break format string, e.g. "\r\n".
+     *
+     * @param string $le
+     */
+    protected static function setLE($le)
+    {
+        static::$LE = $le;
+    }
+
+    /**
+     * Set the public and private key files and password for S/MIME signing.
+     *
+     * @param string $cert_filename
+     * @param string $key_filename
+     * @param string $key_pass            Password for private key
+     * @param string $extracerts_filename Optional path to chain certificate
+     */
+    public function sign($cert_filename, $key_filename, $key_pass, $extracerts_filename = '')
+    {
+        $this->sign_cert_file = $cert_filename;
+        $this->sign_key_file = $key_filename;
+        $this->sign_key_pass = $key_pass;
+        $this->sign_extracerts_file = $extracerts_filename;
+    }
+
+    /**
+     * Quoted-Printable-encode a DKIM header.
+     *
+     * @param string $txt
+     *
+     * @return string
+     */
+    public function DKIM_QP($txt)
+    {
+        $line = '';
+        $len = strlen($txt);
+        for ($i = 0; $i < $len; ++$i) {
+            $ord = ord($txt[$i]);
+            if (((0x21 <= $ord) && ($ord <= 0x3A)) || $ord === 0x3C || ((0x3E <= $ord) && ($ord <= 0x7E))) {
+                $line .= $txt[$i];
+            } else {
+                $line .= '=' . sprintf('%02X', $ord);
+            }
+        }
+
+        return $line;
+    }
+
+    /**
+     * Generate a DKIM signature.
+     *
+     * @param string $signHeader
+     *
+     * @throws Exception
+     *
+     * @return string The DKIM signature value
+     */
+    public function DKIM_Sign($signHeader)
+    {
+        if (!defined('PKCS7_TEXT')) {
+            if ($this->exceptions) {
+                throw new Exception($this->lang('extension_missing') . 'openssl');
+            }
+
+            return '';
+        }
+        $privKeyStr = !empty($this->DKIM_private_string) ?
+            $this->DKIM_private_string :
+            file_get_contents($this->DKIM_private);
+        if ('' !== $this->DKIM_passphrase) {
+            $privKey = openssl_pkey_get_private($privKeyStr, $this->DKIM_passphrase);
+        } else {
+            $privKey = openssl_pkey_get_private($privKeyStr);
+        }
+        if (openssl_sign($signHeader, $signature, $privKey, 'sha256WithRSAEncryption')) {
+            if (\PHP_MAJOR_VERSION < 8) {
+                openssl_pkey_free($privKey);
+            }
+
+            return base64_encode($signature);
+        }
+        if (\PHP_MAJOR_VERSION < 8) {
+            openssl_pkey_free($privKey);
+        }
+
+        return '';
+    }
+
+    /**
+     * Generate a DKIM canonicalization header.
+     * Uses the 'relaxed' algorithm from RFC6376 section 3.4.2.
+     * Canonicalized headers should *always* use CRLF, regardless of mailer setting.
+     *
+     * @see https://tools.ietf.org/html/rfc6376#section-3.4.2
+     *
+     * @param string $signHeader Header
+     *
+     * @return string
+     */
+    public function DKIM_HeaderC($signHeader)
+    {
+        //Normalize breaks to CRLF (regardless of the mailer)
+        $signHeader = static::normalizeBreaks($signHeader, self::CRLF);
+        //Unfold header lines
+        //Note PCRE \s is too broad a definition of whitespace; RFC5322 defines it as `[ \t]`
+        //@see https://tools.ietf.org/html/rfc5322#section-2.2
+        //That means this may break if you do something daft like put vertical tabs in your headers.
+        $signHeader = preg_replace('/\r\n[ \t]+/', ' ', $signHeader);
+        //Break headers out into an array
+        $lines = explode(self::CRLF, $signHeader);
+        foreach ($lines as $key => $line) {
+            //If the header is missing a :, skip it as it's invalid
+            //This is likely to happen because the explode() above will also split
+            //on the trailing LE, leaving an empty line
+            if (strpos($line, ':') === false) {
+                continue;
+            }
+            list($heading, $value) = explode(':', $line, 2);
+            //Lower-case header name
+            $heading = strtolower($heading);
+            //Collapse white space within the value, also convert WSP to space
+            $value = preg_replace('/[ \t]+/', ' ', $value);
+            //RFC6376 is slightly unclear here - it says to delete space at the *end* of each value
+            //But then says to delete space before and after the colon.
+            //Net result is the same as trimming both ends of the value.
+            //By elimination, the same applies to the field name
+            $lines[$key] = trim($heading, " \t") . ':' . trim($value, " \t");
+        }
+
+        return implode(self::CRLF, $lines);
+    }
+
+    /**
+     * Generate a DKIM canonicalization body.
+     * Uses the 'simple' algorithm from RFC6376 section 3.4.3.
+     * Canonicalized bodies should *always* use CRLF, regardless of mailer setting.
+     *
+     * @see https://tools.ietf.org/html/rfc6376#section-3.4.3
+     *
+     * @param string $body Message Body
+     *
+     * @return string
+     */
+    public function DKIM_BodyC($body)
+    {
+        if (empty($body)) {
+            return self::CRLF;
+        }
+        //Normalize line endings to CRLF
+        $body = static::normalizeBreaks($body, self::CRLF);
+
+        //Reduce multiple trailing line breaks to a single one
+        return static::stripTrailingBreaks($body) . self::CRLF;
+    }
+
+    /**
+     * Create the DKIM header and body in a new message header.
+     *
+     * @param string $headers_line Header lines
+     * @param string $subject      Subject
+     * @param string $body         Body
+     *
+     * @throws Exception
+     *
+     * @return string
+     */
+    public function DKIM_Add($headers_line, $subject, $body)
+    {
+        $DKIMsignatureType = 'rsa-sha256'; //Signature & hash algorithms
+        $DKIMcanonicalization = 'relaxed/simple'; //Canonicalization methods of header & body
+        $DKIMquery = 'dns/txt'; //Query method
+        $DKIMtime = time();
+        //Always sign these headers without being asked
+        //Recommended list from https://tools.ietf.org/html/rfc6376#section-5.4.1
+        $autoSignHeaders = [
+            'from',
+            'to',
+            'cc',
+            'date',
+            'subject',
+            'reply-to',
+            'message-id',
+            'content-type',
+            'mime-version',
+            'x-mailer',
+        ];
+        if (stripos($headers_line, 'Subject') === false) {
+            $headers_line .= 'Subject: ' . $subject . static::$LE;
+        }
+        $headerLines = explode(static::$LE, $headers_line);
+        $currentHeaderLabel = '';
+        $currentHeaderValue = '';
+        $parsedHeaders = [];
+        $headerLineIndex = 0;
+        $headerLineCount = count($headerLines);
+        foreach ($headerLines as $headerLine) {
+            $matches = [];
+            if (preg_match('/^([^ \t]*?)(?::[ \t]*)(.*)$/', $headerLine, $matches)) {
+                if ($currentHeaderLabel !== '') {
+                    //We were previously in another header; This is the start of a new header, so save the previous one
+                    $parsedHeaders[] = ['label' => $currentHeaderLabel, 'value' => $currentHeaderValue];
+                }
+                $currentHeaderLabel = $matches[1];
+                $currentHeaderValue = $matches[2];
+            } elseif (preg_match('/^[ \t]+(.*)$/', $headerLine, $matches)) {
+                //This is a folded continuation of the current header, so unfold it
+                $currentHeaderValue .= ' ' . $matches[1];
+            }
+            ++$headerLineIndex;
+            if ($headerLineIndex >= $headerLineCount) {
+                //This was the last line, so finish off this header
+                $parsedHeaders[] = ['label' => $currentHeaderLabel, 'value' => $currentHeaderValue];
+            }
+        }
+        $copiedHeaders = [];
+        $headersToSignKeys = [];
+        $headersToSign = [];
+        foreach ($parsedHeaders as $header) {
+            //Is this header one that must be included in the DKIM signature?
+            if (in_array(strtolower($header['label']), $autoSignHeaders, true)) {
+                $headersToSignKeys[] = $header['label'];
+                $headersToSign[] = $header['label'] . ': ' . $header['value'];
+                if ($this->DKIM_copyHeaderFields) {
+                    $copiedHeaders[] = $header['label'] . ':' . //Note no space after this, as per RFC
+                        str_replace('|', '=7C', $this->DKIM_QP($header['value']));
+                }
+                continue;
+            }
+            //Is this an extra custom header we've been asked to sign?
+            if (in_array($header['label'], $this->DKIM_extraHeaders, true)) {
+                //Find its value in custom headers
+                foreach ($this->CustomHeader as $customHeader) {
+                    if ($customHeader[0] === $header['label']) {
+                        $headersToSignKeys[] = $header['label'];
+                        $headersToSign[] = $header['label'] . ': ' . $header['value'];
+                        if ($this->DKIM_copyHeaderFields) {
+                            $copiedHeaders[] = $header['label'] . ':' . //Note no space after this, as per RFC
+                                str_replace('|', '=7C', $this->DKIM_QP($header['value']));
+                        }
+                        //Skip straight to the next header
+                        continue 2;
+                    }
+                }
+            }
+        }
+        $copiedHeaderFields = '';
+        if ($this->DKIM_copyHeaderFields && count($copiedHeaders) > 0) {
+            //Assemble a DKIM 'z' tag
+            $copiedHeaderFields = ' z=';
+            $first = true;
+            foreach ($copiedHeaders as $copiedHeader) {
+                if (!$first) {
+                    $copiedHeaderFields .= static::$LE . ' |';
+                }
+                //Fold long values
+                if (strlen($copiedHeader) > self::STD_LINE_LENGTH - 3) {
+                    $copiedHeaderFields .= substr(
+                        chunk_split($copiedHeader, self::STD_LINE_LENGTH - 3, static::$LE . self::FWS),
+                        0,
+                        -strlen(static::$LE . self::FWS)
+                    );
+                } else {
+                    $copiedHeaderFields .= $copiedHeader;
+                }
+                $first = false;
+            }
+            $copiedHeaderFields .= ';' . static::$LE;
+        }
+        $headerKeys = ' h=' . implode(':', $headersToSignKeys) . ';' . static::$LE;
+        $headerValues = implode(static::$LE, $headersToSign);
+        $body = $this->DKIM_BodyC($body);
+        //Base64 of packed binary SHA-256 hash of body
+        $DKIMb64 = base64_encode(pack('H*', hash('sha256', $body)));
+        $ident = '';
+        if ('' !== $this->DKIM_identity) {
+            $ident = ' i=' . $this->DKIM_identity . ';' . static::$LE;
+        }
+        //The DKIM-Signature header is included in the signature *except for* the value of the `b` tag
+        //which is appended after calculating the signature
+        //https://tools.ietf.org/html/rfc6376#section-3.5
+        $dkimSignatureHeader = 'DKIM-Signature: v=1;' .
+            ' d=' . $this->DKIM_domain . ';' .
+            ' s=' . $this->DKIM_selector . ';' . static::$LE .
+            ' a=' . $DKIMsignatureType . ';' .
+            ' q=' . $DKIMquery . ';' .
+            ' t=' . $DKIMtime . ';' .
+            ' c=' . $DKIMcanonicalization . ';' . static::$LE .
+            $headerKeys .
+            $ident .
+            $copiedHeaderFields .
+            ' bh=' . $DKIMb64 . ';' . static::$LE .
+            ' b=';
+        //Canonicalize the set of headers
+        $canonicalizedHeaders = $this->DKIM_HeaderC(
+            $headerValues . static::$LE . $dkimSignatureHeader
+        );
+        $signature = $this->DKIM_Sign($canonicalizedHeaders);
+        $signature = trim(chunk_split($signature, self::STD_LINE_LENGTH - 3, static::$LE . self::FWS));
+
+        return static::normalizeBreaks($dkimSignatureHeader . $signature);
+    }
+
+    /**
+     * Detect if a string contains a line longer than the maximum line length
+     * allowed by RFC 2822 section 2.1.1.
+     *
+     * @param string $str
+     *
+     * @return bool
+     */
+    public static function hasLineLongerThanMax($str)
+    {
+        return (bool) preg_match('/^(.{' . (self::MAX_LINE_LENGTH + strlen(static::$LE)) . ',})/m', $str);
+    }
+
+    /**
+     * If a string contains any "special" characters, double-quote the name,
+     * and escape any double quotes with a backslash.
+     *
+     * @param string $str
+     *
+     * @return string
+     *
+     * @see RFC822 3.4.1
+     */
+    public static function quotedString($str)
+    {
+        if (preg_match('/[ ()<>@,;:"\/\[\]?=]/', $str)) {
+            //If the string contains any of these chars, it must be double-quoted
+            //and any double quotes must be escaped with a backslash
+            return '"' . str_replace('"', '\\"', $str) . '"';
+        }
+
+        //Return the string untouched, it doesn't need quoting
+        return $str;
+    }
+
+    /**
+     * Allows for public read access to 'to' property.
+     * Before the send() call, queued addresses (i.e. with IDN) are not yet included.
+     *
+     * @return array
+     */
+    public function getToAddresses()
+    {
+        return $this->to;
+    }
+
+    /**
+     * Allows for public read access to 'cc' property.
+     * Before the send() call, queued addresses (i.e. with IDN) are not yet included.
+     *
+     * @return array
+     */
+    public function getCcAddresses()
+    {
+        return $this->cc;
+    }
+
+    /**
+     * Allows for public read access to 'bcc' property.
+     * Before the send() call, queued addresses (i.e. with IDN) are not yet included.
+     *
+     * @return array
+     */
+    public function getBccAddresses()
+    {
+        return $this->bcc;
+    }
+
+    /**
+     * Allows for public read access to 'ReplyTo' property.
+     * Before the send() call, queued addresses (i.e. with IDN) are not yet included.
+     *
+     * @return array
+     */
+    public function getReplyToAddresses()
+    {
+        return $this->ReplyTo;
+    }
+
+    /**
+     * Allows for public read access to 'all_recipients' property.
+     * Before the send() call, queued addresses (i.e. with IDN) are not yet included.
+     *
+     * @return array
+     */
+    public function getAllRecipientAddresses()
+    {
+        return $this->all_recipients;
+    }
+
+    /**
+     * Perform a callback.
+     *
+     * @param bool   $isSent
+     * @param array  $to
+     * @param array  $cc
+     * @param array  $bcc
+     * @param string $subject
+     * @param string $body
+     * @param string $from
+     * @param array  $extra
+     */
+    protected function doCallback($isSent, $to, $cc, $bcc, $subject, $body, $from, $extra)
+    {
+        if (!empty($this->action_function) && is_callable($this->action_function)) {
+            call_user_func($this->action_function, $isSent, $to, $cc, $bcc, $subject, $body, $from, $extra);
+        }
+    }
+
+    /**
+     * Get the OAuthTokenProvider instance.
+     *
+     * @return OAuthTokenProvider
+     */
+    public function getOAuth()
+    {
+        return $this->oauth;
+    }
+
+    /**
+     * Set an OAuthTokenProvider instance.
+     */
+    public function setOAuth(OAuthTokenProvider $oauth)
+    {
+        $this->oauth = $oauth;
+    }
+}
diff --git a/src/lib/PHPMailer/POP3.php b/src/lib/PHPMailer/POP3.php
new file mode 100644
index 0000000..b92a1f2
--- /dev/null
+++ b/src/lib/PHPMailer/POP3.php
@@ -0,0 +1,467 @@
+<?php
+
+/**
+ * PHPMailer POP-Before-SMTP Authentication Class.
+ * PHP Version 5.5.
+ *
+ * @see https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * PHPMailer POP-Before-SMTP Authentication Class.
+ * Specifically for PHPMailer to use for RFC1939 POP-before-SMTP authentication.
+ * 1) This class does not support APOP authentication.
+ * 2) Opening and closing lots of POP3 connections can be quite slow. If you need
+ *   to send a batch of emails then just perform the authentication once at the start,
+ *   and then loop through your mail sending script. Providing this process doesn't
+ *   take longer than the verification period lasts on your POP3 server, you should be fine.
+ * 3) This is really ancient technology; you should only need to use it to talk to very old systems.
+ * 4) This POP3 class is deliberately lightweight and incomplete, implementing just
+ *   enough to do authentication.
+ *   If you want a more complete class there are other POP3 classes for PHP available.
+ *
+ * @author Richard Davey (original author) <rich@corephp.co.uk>
+ * @author Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ */
+class POP3
+{
+    /**
+     * The POP3 PHPMailer Version number.
+     *
+     * @var string
+     */
+    const VERSION = '6.8.1';
+
+    /**
+     * Default POP3 port number.
+     *
+     * @var int
+     */
+    const DEFAULT_PORT = 110;
+
+    /**
+     * Default timeout in seconds.
+     *
+     * @var int
+     */
+    const DEFAULT_TIMEOUT = 30;
+
+    /**
+     * POP3 class debug output mode.
+     * Debug output level.
+     * Options:
+     * @see POP3::DEBUG_OFF: No output
+     * @see POP3::DEBUG_SERVER: Server messages, connection/server errors
+     * @see POP3::DEBUG_CLIENT: Client and Server messages, connection/server errors
+     *
+     * @var int
+     */
+    public $do_debug = self::DEBUG_OFF;
+
+    /**
+     * POP3 mail server hostname.
+     *
+     * @var string
+     */
+    public $host;
+
+    /**
+     * POP3 port number.
+     *
+     * @var int
+     */
+    public $port;
+
+    /**
+     * POP3 Timeout Value in seconds.
+     *
+     * @var int
+     */
+    public $tval;
+
+    /**
+     * POP3 username.
+     *
+     * @var string
+     */
+    public $username;
+
+    /**
+     * POP3 password.
+     *
+     * @var string
+     */
+    public $password;
+
+    /**
+     * Resource handle for the POP3 connection socket.
+     *
+     * @var resource
+     */
+    protected $pop_conn;
+
+    /**
+     * Are we connected?
+     *
+     * @var bool
+     */
+    protected $connected = false;
+
+    /**
+     * Error container.
+     *
+     * @var array
+     */
+    protected $errors = [];
+
+    /**
+     * Line break constant.
+     */
+    const LE = "\r\n";
+
+    /**
+     * Debug level for no output.
+     *
+     * @var int
+     */
+    const DEBUG_OFF = 0;
+
+    /**
+     * Debug level to show server -> client messages
+     * also shows clients connection errors or errors from server
+     *
+     * @var int
+     */
+    const DEBUG_SERVER = 1;
+
+    /**
+     * Debug level to show client -> server and server -> client messages.
+     *
+     * @var int
+     */
+    const DEBUG_CLIENT = 2;
+
+    /**
+     * Simple static wrapper for all-in-one POP before SMTP.
+     *
+     * @param string   $host        The hostname to connect to
+     * @param int|bool $port        The port number to connect to
+     * @param int|bool $timeout     The timeout value
+     * @param string   $username
+     * @param string   $password
+     * @param int      $debug_level
+     *
+     * @return bool
+     */
+    public static function popBeforeSmtp(
+        $host,
+        $port = false,
+        $timeout = false,
+        $username = '',
+        $password = '',
+        $debug_level = 0
+    ) {
+        $pop = new self();
+
+        return $pop->authorise($host, $port, $timeout, $username, $password, $debug_level);
+    }
+
+    /**
+     * Authenticate with a POP3 server.
+     * A connect, login, disconnect sequence
+     * appropriate for POP-before SMTP authorisation.
+     *
+     * @param string   $host        The hostname to connect to
+     * @param int|bool $port        The port number to connect to
+     * @param int|bool $timeout     The timeout value
+     * @param string   $username
+     * @param string   $password
+     * @param int      $debug_level
+     *
+     * @return bool
+     */
+    public function authorise($host, $port = false, $timeout = false, $username = '', $password = '', $debug_level = 0)
+    {
+        $this->host = $host;
+        //If no port value provided, use default
+        if (false === $port) {
+            $this->port = static::DEFAULT_PORT;
+        } else {
+            $this->port = (int) $port;
+        }
+        //If no timeout value provided, use default
+        if (false === $timeout) {
+            $this->tval = static::DEFAULT_TIMEOUT;
+        } else {
+            $this->tval = (int) $timeout;
+        }
+        $this->do_debug = $debug_level;
+        $this->username = $username;
+        $this->password = $password;
+        //Reset the error log
+        $this->errors = [];
+        //Connect
+        $result = $this->connect($this->host, $this->port, $this->tval);
+        if ($result) {
+            $login_result = $this->login($this->username, $this->password);
+            if ($login_result) {
+                $this->disconnect();
+
+                return true;
+            }
+        }
+        //We need to disconnect regardless of whether the login succeeded
+        $this->disconnect();
+
+        return false;
+    }
+
+    /**
+     * Connect to a POP3 server.
+     *
+     * @param string   $host
+     * @param int|bool $port
+     * @param int      $tval
+     *
+     * @return bool
+     */
+    public function connect($host, $port = false, $tval = 30)
+    {
+        //Are we already connected?
+        if ($this->connected) {
+            return true;
+        }
+
+        //On Windows this will raise a PHP Warning error if the hostname doesn't exist.
+        //Rather than suppress it with @fsockopen, capture it cleanly instead
+        set_error_handler([$this, 'catchWarning']);
+
+        if (false === $port) {
+            $port = static::DEFAULT_PORT;
+        }
+
+        //Connect to the POP3 server
+        $errno = 0;
+        $errstr = '';
+        $this->pop_conn = fsockopen(
+            $host, //POP3 Host
+            $port, //Port #
+            $errno, //Error Number
+            $errstr, //Error Message
+            $tval
+        ); //Timeout (seconds)
+        //Restore the error handler
+        restore_error_handler();
+
+        //Did we connect?
+        if (false === $this->pop_conn) {
+            //It would appear not...
+            $this->setError(
+                "Failed to connect to server $host on port $port. errno: $errno; errstr: $errstr"
+            );
+
+            return false;
+        }
+
+        //Increase the stream time-out
+        stream_set_timeout($this->pop_conn, $tval, 0);
+
+        //Get the POP3 server response
+        $pop3_response = $this->getResponse();
+        //Check for the +OK
+        if ($this->checkResponse($pop3_response)) {
+            //The connection is established and the POP3 server is talking
+            $this->connected = true;
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Log in to the POP3 server.
+     * Does not support APOP (RFC 2828, 4949).
+     *
+     * @param string $username
+     * @param string $password
+     *
+     * @return bool
+     */
+    public function login($username = '', $password = '')
+    {
+        if (!$this->connected) {
+            $this->setError('Not connected to POP3 server');
+            return false;
+        }
+        if (empty($username)) {
+            $username = $this->username;
+        }
+        if (empty($password)) {
+            $password = $this->password;
+        }
+
+        //Send the Username
+        $this->sendString("USER $username" . static::LE);
+        $pop3_response = $this->getResponse();
+        if ($this->checkResponse($pop3_response)) {
+            //Send the Password
+            $this->sendString("PASS $password" . static::LE);
+            $pop3_response = $this->getResponse();
+            if ($this->checkResponse($pop3_response)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Disconnect from the POP3 server.
+     */
+    public function disconnect()
+    {
+        // If could not connect at all, no need to disconnect
+        if ($this->pop_conn === false) {
+            return;
+        }
+
+        $this->sendString('QUIT' . static::LE);
+
+        // RFC 1939 shows POP3 server sending a +OK response to the QUIT command.
+        // Try to get it.  Ignore any failures here.
+        try {
+            $this->getResponse();
+        } catch (Exception $e) {
+            //Do nothing
+        }
+
+        //The QUIT command may cause the daemon to exit, which will kill our connection
+        //So ignore errors here
+        try {
+            @fclose($this->pop_conn);
+        } catch (Exception $e) {
+            //Do nothing
+        }
+
+        // Clean up attributes.
+        $this->connected = false;
+        $this->pop_conn  = false;
+    }
+
+    /**
+     * Get a response from the POP3 server.
+     *
+     * @param int $size The maximum number of bytes to retrieve
+     *
+     * @return string
+     */
+    protected function getResponse($size = 128)
+    {
+        $response = fgets($this->pop_conn, $size);
+        if ($this->do_debug >= self::DEBUG_SERVER) {
+            echo 'Server -> Client: ', $response;
+        }
+
+        return $response;
+    }
+
+    /**
+     * Send raw data to the POP3 server.
+     *
+     * @param string $string
+     *
+     * @return int
+     */
+    protected function sendString($string)
+    {
+        if ($this->pop_conn) {
+            if ($this->do_debug >= self::DEBUG_CLIENT) { //Show client messages when debug >= 2
+                echo 'Client -> Server: ', $string;
+            }
+
+            return fwrite($this->pop_conn, $string, strlen($string));
+        }
+
+        return 0;
+    }
+
+    /**
+     * Checks the POP3 server response.
+     * Looks for for +OK or -ERR.
+     *
+     * @param string $string
+     *
+     * @return bool
+     */
+    protected function checkResponse($string)
+    {
+        if (strpos($string, '+OK') !== 0) {
+            $this->setError("Server reported an error: $string");
+
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Add an error to the internal error store.
+     * Also display debug output if it's enabled.
+     *
+     * @param string $error
+     */
+    protected function setError($error)
+    {
+        $this->errors[] = $error;
+        if ($this->do_debug >= self::DEBUG_SERVER) {
+            echo '<pre>';
+            foreach ($this->errors as $e) {
+                print_r($e);
+            }
+            echo '</pre>';
+        }
+    }
+
+    /**
+     * Get an array of error messages, if any.
+     *
+     * @return array
+     */
+    public function getErrors()
+    {
+        return $this->errors;
+    }
+
+    /**
+     * POP3 connection error handler.
+     *
+     * @param int    $errno
+     * @param string $errstr
+     * @param string $errfile
+     * @param int    $errline
+     */
+    protected function catchWarning($errno, $errstr, $errfile, $errline)
+    {
+        $this->setError(
+            'Connecting to the POP3 server raised a PHP warning:' .
+            "errno: $errno errstr: $errstr; errfile: $errfile; errline: $errline"
+        );
+    }
+}
diff --git a/src/lib/PHPMailer/SMTP.php b/src/lib/PHPMailer/SMTP.php
new file mode 100644
index 0000000..2b63840
--- /dev/null
+++ b/src/lib/PHPMailer/SMTP.php
@@ -0,0 +1,1466 @@
+<?php
+
+/**
+ * PHPMailer RFC821 SMTP email transport class.
+ * PHP Version 5.5.
+ *
+ * @see       https://github.com/PHPMailer/PHPMailer/ The PHPMailer GitHub project
+ *
+ * @author    Marcus Bointon (Synchro/coolbru) <phpmailer@synchromedia.co.uk>
+ * @author    Jim Jagielski (jimjag) <jimjag@gmail.com>
+ * @author    Andy Prevost (codeworxtech) <codeworxtech@users.sourceforge.net>
+ * @author    Brent R. Matzelle (original founder)
+ * @copyright 2012 - 2020 Marcus Bointon
+ * @copyright 2010 - 2012 Jim Jagielski
+ * @copyright 2004 - 2009 Andy Prevost
+ * @license   http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
+ * @note      This program is distributed in the hope that it will be useful - WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+namespace PHPMailer\PHPMailer;
+
+/**
+ * PHPMailer RFC821 SMTP email transport class.
+ * Implements RFC 821 SMTP commands and provides some utility methods for sending mail to an SMTP server.
+ *
+ * @author Chris Ryan
+ * @author Marcus Bointon <phpmailer@synchromedia.co.uk>
+ */
+class SMTP
+{
+    /**
+     * The PHPMailer SMTP version number.
+     *
+     * @var string
+     */
+    const VERSION = '6.8.1';
+
+    /**
+     * SMTP line break constant.
+     *
+     * @var string
+     */
+    const LE = "\r\n";
+
+    /**
+     * The SMTP port to use if one is not specified.
+     *
+     * @var int
+     */
+    const DEFAULT_PORT = 25;
+
+    /**
+     * The SMTPs port to use if one is not specified.
+     *
+     * @var int
+     */
+    const DEFAULT_SECURE_PORT = 465;
+
+    /**
+     * The maximum line length allowed by RFC 5321 section 4.5.3.1.6,
+     * *excluding* a trailing CRLF break.
+     *
+     * @see https://tools.ietf.org/html/rfc5321#section-4.5.3.1.6
+     *
+     * @var int
+     */
+    const MAX_LINE_LENGTH = 998;
+
+    /**
+     * The maximum line length allowed for replies in RFC 5321 section 4.5.3.1.5,
+     * *including* a trailing CRLF line break.
+     *
+     * @see https://tools.ietf.org/html/rfc5321#section-4.5.3.1.5
+     *
+     * @var int
+     */
+    const MAX_REPLY_LENGTH = 512;
+
+    /**
+     * Debug level for no output.
+     *
+     * @var int
+     */
+    const DEBUG_OFF = 0;
+
+    /**
+     * Debug level to show client -> server messages.
+     *
+     * @var int
+     */
+    const DEBUG_CLIENT = 1;
+
+    /**
+     * Debug level to show client -> server and server -> client messages.
+     *
+     * @var int
+     */
+    const DEBUG_SERVER = 2;
+
+    /**
+     * Debug level to show connection status, client -> server and server -> client messages.
+     *
+     * @var int
+     */
+    const DEBUG_CONNECTION = 3;
+
+    /**
+     * Debug level to show all messages.
+     *
+     * @var int
+     */
+    const DEBUG_LOWLEVEL = 4;
+
+    /**
+     * Debug output level.
+     * Options:
+     * * self::DEBUG_OFF (`0`) No debug output, default
+     * * self::DEBUG_CLIENT (`1`) Client commands
+     * * self::DEBUG_SERVER (`2`) Client commands and server responses
+     * * self::DEBUG_CONNECTION (`3`) As DEBUG_SERVER plus connection status
+     * * self::DEBUG_LOWLEVEL (`4`) Low-level data output, all messages.
+     *
+     * @var int
+     */
+    public $do_debug = self::DEBUG_OFF;
+
+    /**
+     * How to handle debug output.
+     * Options:
+     * * `echo` Output plain-text as-is, appropriate for CLI
+     * * `html` Output escaped, line breaks converted to `<br>`, appropriate for browser output
+     * * `error_log` Output to error log as configured in php.ini
+     * Alternatively, you can provide a callable expecting two params: a message string and the debug level:
+     *
+     * ```php
+     * $smtp->Debugoutput = function($str, $level) {echo "debug level $level; message: $str";};
+     * ```
+     *
+     * Alternatively, you can pass in an instance of a PSR-3 compatible logger, though only `debug`
+     * level output is used:
+     *
+     * ```php
+     * $mail->Debugoutput = new myPsr3Logger;
+     * ```
+     *
+     * @var string|callable|\Psr\Log\LoggerInterface
+     */
+    public $Debugoutput = 'echo';
+
+    /**
+     * Whether to use VERP.
+     *
+     * @see http://en.wikipedia.org/wiki/Variable_envelope_return_path
+     * @see http://www.postfix.org/VERP_README.html Info on VERP
+     *
+     * @var bool
+     */
+    public $do_verp = false;
+
+    /**
+     * The timeout value for connection, in seconds.
+     * Default of 5 minutes (300sec) is from RFC2821 section 4.5.3.2.
+     * This needs to be quite high to function correctly with hosts using greetdelay as an anti-spam measure.
+     *
+     * @see http://tools.ietf.org/html/rfc2821#section-4.5.3.2
+     *
+     * @var int
+     */
+    public $Timeout = 300;
+
+    /**
+     * How long to wait for commands to complete, in seconds.
+     * Default of 5 minutes (300sec) is from RFC2821 section 4.5.3.2.
+     *
+     * @var int
+     */
+    public $Timelimit = 300;
+
+    /**
+     * Patterns to extract an SMTP transaction id from reply to a DATA command.
+     * The first capture group in each regex will be used as the ID.
+     * MS ESMTP returns the message ID, which may not be correct for internal tracking.
+     *
+     * @var string[]
+     */
+    protected $smtp_transaction_id_patterns = [
+        'exim' => '/[\d]{3} OK id=(.*)/',
+        'sendmail' => '/[\d]{3} 2.0.0 (.*) Message/',
+        'postfix' => '/[\d]{3} 2.0.0 Ok: queued as (.*)/',
+        'Microsoft_ESMTP' => '/[0-9]{3} 2.[\d].0 (.*)@(?:.*) Queued mail for delivery/',
+        'Amazon_SES' => '/[\d]{3} Ok (.*)/',
+        'SendGrid' => '/[\d]{3} Ok: queued as (.*)/',
+        'CampaignMonitor' => '/[\d]{3} 2.0.0 OK:([a-zA-Z\d]{48})/',
+        'Haraka' => '/[\d]{3} Message Queued \((.*)\)/',
+        'ZoneMTA' => '/[\d]{3} Message queued as (.*)/',
+        'Mailjet' => '/[\d]{3} OK queued as (.*)/',
+    ];
+
+    /**
+     * The last transaction ID issued in response to a DATA command,
+     * if one was detected.
+     *
+     * @var string|bool|null
+     */
+    protected $last_smtp_transaction_id;
+
+    /**
+     * The socket for the server connection.
+     *
+     * @var ?resource
+     */
+    protected $smtp_conn;
+
+    /**
+     * Error information, if any, for the last SMTP command.
+     *
+     * @var array
+     */
+    protected $error = [
+        'error' => '',
+        'detail' => '',
+        'smtp_code' => '',
+        'smtp_code_ex' => '',
+    ];
+
+    /**
+     * The reply the server sent to us for HELO.
+     * If null, no HELO string has yet been received.
+     *
+     * @var string|null
+     */
+    protected $helo_rply;
+
+    /**
+     * The set of SMTP extensions sent in reply to EHLO command.
+     * Indexes of the array are extension names.
+     * Value at index 'HELO' or 'EHLO' (according to command that was sent)
+     * represents the server name. In case of HELO it is the only element of the array.
+     * Other values can be boolean TRUE or an array containing extension options.
+     * If null, no HELO/EHLO string has yet been received.
+     *
+     * @var array|null
+     */
+    protected $server_caps;
+
+    /**
+     * The most recent reply received from the server.
+     *
+     * @var string
+     */
+    protected $last_reply = '';
+
+    /**
+     * Output debugging info via a user-selected method.
+     *
+     * @param string $str   Debug string to output
+     * @param int    $level The debug level of this message; see DEBUG_* constants
+     *
+     * @see SMTP::$Debugoutput
+     * @see SMTP::$do_debug
+     */
+    protected function edebug($str, $level = 0)
+    {
+        if ($level > $this->do_debug) {
+            return;
+        }
+        //Is this a PSR-3 logger?
+        if ($this->Debugoutput instanceof \Psr\Log\LoggerInterface) {
+            $this->Debugoutput->debug($str);
+
+            return;
+        }
+        //Avoid clash with built-in function names
+        if (is_callable($this->Debugoutput) && !in_array($this->Debugoutput, ['error_log', 'html', 'echo'])) {
+            call_user_func($this->Debugoutput, $str, $level);
+
+            return;
+        }
+        switch ($this->Debugoutput) {
+            case 'error_log':
+                //Don't output, just log
+                error_log($str);
+                break;
+            case 'html':
+                //Cleans up output a bit for a better looking, HTML-safe output
+                echo gmdate('Y-m-d H:i:s'), ' ', htmlentities(
+                    preg_replace('/[\r\n]+/', '', $str),
+                    ENT_QUOTES,
+                    'UTF-8'
+                ), "<br>\n";
+                break;
+            case 'echo':
+            default:
+                //Normalize line breaks
+                $str = preg_replace('/\r\n|\r/m', "\n", $str);
+                echo gmdate('Y-m-d H:i:s'),
+                "\t",
+                    //Trim trailing space
+                trim(
+                    //Indent for readability, except for trailing break
+                    str_replace(
+                        "\n",
+                        "\n                   \t                  ",
+                        trim($str)
+                    )
+                ),
+                "\n";
+        }
+    }
+
+    /**
+     * Connect to an SMTP server.
+     *
+     * @param string $host    SMTP server IP or host name
+     * @param int    $port    The port number to connect to
+     * @param int    $timeout How long to wait for the connection to open
+     * @param array  $options An array of options for stream_context_create()
+     *
+     * @return bool
+     */
+    public function connect($host, $port = null, $timeout = 30, $options = [])
+    {
+        //Clear errors to avoid confusion
+        $this->setError('');
+        //Make sure we are __not__ connected
+        if ($this->connected()) {
+            //Already connected, generate error
+            $this->setError('Already connected to a server');
+
+            return false;
+        }
+        if (empty($port)) {
+            $port = self::DEFAULT_PORT;
+        }
+        //Connect to the SMTP server
+        $this->edebug(
+            "Connection: opening to $host:$port, timeout=$timeout, options=" .
+            (count($options) > 0 ? var_export($options, true) : 'array()'),
+            self::DEBUG_CONNECTION
+        );
+
+        $this->smtp_conn = $this->getSMTPConnection($host, $port, $timeout, $options);
+
+        if ($this->smtp_conn === false) {
+            //Error info already set inside `getSMTPConnection()`
+            return false;
+        }
+
+        $this->edebug('Connection: opened', self::DEBUG_CONNECTION);
+
+        //Get any announcement
+        $this->last_reply = $this->get_lines();
+        $this->edebug('SERVER -> CLIENT: ' . $this->last_reply, self::DEBUG_SERVER);
+        $responseCode = (int)substr($this->last_reply, 0, 3);
+        if ($responseCode === 220) {
+            return true;
+        }
+        //Anything other than a 220 response means something went wrong
+        //RFC 5321 says the server will wait for us to send a QUIT in response to a 554 error
+        //https://tools.ietf.org/html/rfc5321#section-3.1
+        if ($responseCode === 554) {
+            $this->quit();
+        }
+        //This will handle 421 responses which may not wait for a QUIT (e.g. if the server is being shut down)
+        $this->edebug('Connection: closing due to error', self::DEBUG_CONNECTION);
+        $this->close();
+        return false;
+    }
+
+    /**
+     * Create connection to the SMTP server.
+     *
+     * @param string $host    SMTP server IP or host name
+     * @param int    $port    The port number to connect to
+     * @param int    $timeout How long to wait for the connection to open
+     * @param array  $options An array of options for stream_context_create()
+     *
+     * @return false|resource
+     */
+    protected function getSMTPConnection($host, $port = null, $timeout = 30, $options = [])
+    {
+        static $streamok;
+        //This is enabled by default since 5.0.0 but some providers disable it
+        //Check this once and cache the result
+        if (null === $streamok) {
+            $streamok = function_exists('stream_socket_client');
+        }
+
+        $errno = 0;
+        $errstr = '';
+        if ($streamok) {
+            $socket_context = stream_context_create($options);
+            set_error_handler([$this, 'errorHandler']);
+            $connection = stream_socket_client(
+                $host . ':' . $port,
+                $errno,
+                $errstr,
+                $timeout,
+                STREAM_CLIENT_CONNECT,
+                $socket_context
+            );
+        } else {
+            //Fall back to fsockopen which should work in more places, but is missing some features
+            $this->edebug(
+                'Connection: stream_socket_client not available, falling back to fsockopen',
+                self::DEBUG_CONNECTION
+            );
+            set_error_handler([$this, 'errorHandler']);
+            $connection = fsockopen(
+                $host,
+                $port,
+                $errno,
+                $errstr,
+                $timeout
+            );
+        }
+        restore_error_handler();
+
+        //Verify we connected properly
+        if (!is_resource($connection)) {
+            $this->setError(
+                'Failed to connect to server',
+                '',
+                (string) $errno,
+                $errstr
+            );
+            $this->edebug(
+                'SMTP ERROR: ' . $this->error['error']
+                . ": $errstr ($errno)",
+                self::DEBUG_CLIENT
+            );
+
+            return false;
+        }
+
+        //SMTP server can take longer to respond, give longer timeout for first read
+        //Windows does not have support for this timeout function
+        if (strpos(PHP_OS, 'WIN') !== 0) {
+            $max = (int)ini_get('max_execution_time');
+            //Don't bother if unlimited, or if set_time_limit is disabled
+            if (0 !== $max && $timeout > $max && strpos(ini_get('disable_functions'), 'set_time_limit') === false) {
+                @set_time_limit($timeout);
+            }
+            stream_set_timeout($connection, $timeout, 0);
+        }
+
+        return $connection;
+    }
+
+    /**
+     * Initiate a TLS (encrypted) session.
+     *
+     * @return bool
+     */
+    public function startTLS()
+    {
+        if (!$this->sendCommand('STARTTLS', 'STARTTLS', 220)) {
+            return false;
+        }
+
+        //Allow the best TLS version(s) we can
+        $crypto_method = STREAM_CRYPTO_METHOD_TLS_CLIENT;
+
+        //PHP 5.6.7 dropped inclusion of TLS 1.1 and 1.2 in STREAM_CRYPTO_METHOD_TLS_CLIENT
+        //so add them back in manually if we can
+        if (defined('STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT')) {
+            $crypto_method |= STREAM_CRYPTO_METHOD_TLSv1_2_CLIENT;
+            $crypto_method |= STREAM_CRYPTO_METHOD_TLSv1_1_CLIENT;
+        }
+
+        //Begin encrypted connection
+        set_error_handler([$this, 'errorHandler']);
+        $crypto_ok = stream_socket_enable_crypto(
+            $this->smtp_conn,
+            true,
+            $crypto_method
+        );
+        restore_error_handler();
+
+        return (bool) $crypto_ok;
+    }
+
+    /**
+     * Perform SMTP authentication.
+     * Must be run after hello().
+     *
+     * @see    hello()
+     *
+     * @param string $username The user name
+     * @param string $password The password
+     * @param string $authtype The auth type (CRAM-MD5, PLAIN, LOGIN, XOAUTH2)
+     * @param OAuthTokenProvider $OAuth An optional OAuthTokenProvider instance for XOAUTH2 authentication
+     *
+     * @return bool True if successfully authenticated
+     */
+    public function authenticate(
+        $username,
+        $password,
+        $authtype = null,
+        $OAuth = null
+    ) {
+        if (!$this->server_caps) {
+            $this->setError('Authentication is not allowed before HELO/EHLO');
+
+            return false;
+        }
+
+        if (array_key_exists('EHLO', $this->server_caps)) {
+            //SMTP extensions are available; try to find a proper authentication method
+            if (!array_key_exists('AUTH', $this->server_caps)) {
+                $this->setError('Authentication is not allowed at this stage');
+                //'at this stage' means that auth may be allowed after the stage changes
+                //e.g. after STARTTLS
+
+                return false;
+            }
+
+            $this->edebug('Auth method requested: ' . ($authtype ?: 'UNSPECIFIED'), self::DEBUG_LOWLEVEL);
+            $this->edebug(
+                'Auth methods available on the server: ' . implode(',', $this->server_caps['AUTH']),
+                self::DEBUG_LOWLEVEL
+            );
+
+            //If we have requested a specific auth type, check the server supports it before trying others
+            if (null !== $authtype && !in_array($authtype, $this->server_caps['AUTH'], true)) {
+                $this->edebug('Requested auth method not available: ' . $authtype, self::DEBUG_LOWLEVEL);
+                $authtype = null;
+            }
+
+            if (empty($authtype)) {
+                //If no auth mechanism is specified, attempt to use these, in this order
+                //Try CRAM-MD5 first as it's more secure than the others
+                foreach (['CRAM-MD5', 'LOGIN', 'PLAIN', 'XOAUTH2'] as $method) {
+                    if (in_array($method, $this->server_caps['AUTH'], true)) {
+                        $authtype = $method;
+                        break;
+                    }
+                }
+                if (empty($authtype)) {
+                    $this->setError('No supported authentication methods found');
+
+                    return false;
+                }
+                $this->edebug('Auth method selected: ' . $authtype, self::DEBUG_LOWLEVEL);
+            }
+
+            if (!in_array($authtype, $this->server_caps['AUTH'], true)) {
+                $this->setError("The requested authentication method \"$authtype\" is not supported by the server");
+
+                return false;
+            }
+        } elseif (empty($authtype)) {
+            $authtype = 'LOGIN';
+        }
+        switch ($authtype) {
+            case 'PLAIN':
+                //Start authentication
+                if (!$this->sendCommand('AUTH', 'AUTH PLAIN', 334)) {
+                    return false;
+                }
+                //Send encoded username and password
+                if (
+                    //Format from https://tools.ietf.org/html/rfc4616#section-2
+                    //We skip the first field (it's forgery), so the string starts with a null byte
+                    !$this->sendCommand(
+                        'User & Password',
+                        base64_encode("\0" . $username . "\0" . $password),
+                        235
+                    )
+                ) {
+                    return false;
+                }
+                break;
+            case 'LOGIN':
+                //Start authentication
+                if (!$this->sendCommand('AUTH', 'AUTH LOGIN', 334)) {
+                    return false;
+                }
+                if (!$this->sendCommand('Username', base64_encode($username), 334)) {
+                    return false;
+                }
+                if (!$this->sendCommand('Password', base64_encode($password), 235)) {
+                    return false;
+                }
+                break;
+            case 'CRAM-MD5':
+                //Start authentication
+                if (!$this->sendCommand('AUTH CRAM-MD5', 'AUTH CRAM-MD5', 334)) {
+                    return false;
+                }
+                //Get the challenge
+                $challenge = base64_decode(substr($this->last_reply, 4));
+
+                //Build the response
+                $response = $username . ' ' . $this->hmac($challenge, $password);
+
+                //send encoded credentials
+                return $this->sendCommand('Username', base64_encode($response), 235);
+            case 'XOAUTH2':
+                //The OAuth instance must be set up prior to requesting auth.
+                if (null === $OAuth) {
+                    return false;
+                }
+                $oauth = $OAuth->getOauth64();
+
+                //Start authentication
+                if (!$this->sendCommand('AUTH', 'AUTH XOAUTH2 ' . $oauth, 235)) {
+                    return false;
+                }
+                break;
+            default:
+                $this->setError("Authentication method \"$authtype\" is not supported");
+
+                return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Calculate an MD5 HMAC hash.
+     * Works like hash_hmac('md5', $data, $key)
+     * in case that function is not available.
+     *
+     * @param string $data The data to hash
+     * @param string $key  The key to hash with
+     *
+     * @return string
+     */
+    protected function hmac($data, $key)
+    {
+        if (function_exists('hash_hmac')) {
+            return hash_hmac('md5', $data, $key);
+        }
+
+        //The following borrowed from
+        //http://php.net/manual/en/function.mhash.php#27225
+
+        //RFC 2104 HMAC implementation for php.
+        //Creates an md5 HMAC.
+        //Eliminates the need to install mhash to compute a HMAC
+        //by Lance Rushing
+
+        $bytelen = 64; //byte length for md5
+        if (strlen($key) > $bytelen) {
+            $key = pack('H*', md5($key));
+        }
+        $key = str_pad($key, $bytelen, chr(0x00));
+        $ipad = str_pad('', $bytelen, chr(0x36));
+        $opad = str_pad('', $bytelen, chr(0x5c));
+        $k_ipad = $key ^ $ipad;
+        $k_opad = $key ^ $opad;
+
+        return md5($k_opad . pack('H*', md5($k_ipad . $data)));
+    }
+
+    /**
+     * Check connection state.
+     *
+     * @return bool True if connected
+     */
+    public function connected()
+    {
+        if (is_resource($this->smtp_conn)) {
+            $sock_status = stream_get_meta_data($this->smtp_conn);
+            if ($sock_status['eof']) {
+                //The socket is valid but we are not connected
+                $this->edebug(
+                    'SMTP NOTICE: EOF caught while checking if connected',
+                    self::DEBUG_CLIENT
+                );
+                $this->close();
+
+                return false;
+            }
+
+            return true; //everything looks good
+        }
+
+        return false;
+    }
+
+    /**
+     * Close the socket and clean up the state of the class.
+     * Don't use this function without first trying to use QUIT.
+     *
+     * @see quit()
+     */
+    public function close()
+    {
+        $this->server_caps = null;
+        $this->helo_rply = null;
+        if (is_resource($this->smtp_conn)) {
+            //Close the connection and cleanup
+            fclose($this->smtp_conn);
+            $this->smtp_conn = null; //Makes for cleaner serialization
+            $this->edebug('Connection: closed', self::DEBUG_CONNECTION);
+        }
+    }
+
+    /**
+     * Send an SMTP DATA command.
+     * Issues a data command and sends the msg_data to the server,
+     * finalizing the mail transaction. $msg_data is the message
+     * that is to be sent with the headers. Each header needs to be
+     * on a single line followed by a <CRLF> with the message headers
+     * and the message body being separated by an additional <CRLF>.
+     * Implements RFC 821: DATA <CRLF>.
+     *
+     * @param string $msg_data Message data to send
+     *
+     * @return bool
+     */
+    public function data($msg_data)
+    {
+        //This will use the standard timelimit
+        if (!$this->sendCommand('DATA', 'DATA', 354)) {
+            return false;
+        }
+
+        /* The server is ready to accept data!
+         * According to rfc821 we should not send more than 1000 characters on a single line (including the LE)
+         * so we will break the data up into lines by \r and/or \n then if needed we will break each of those into
+         * smaller lines to fit within the limit.
+         * We will also look for lines that start with a '.' and prepend an additional '.'.
+         * NOTE: this does not count towards line-length limit.
+         */
+
+        //Normalize line breaks before exploding
+        $lines = explode("\n", str_replace(["\r\n", "\r"], "\n", $msg_data));
+
+        /* To distinguish between a complete RFC822 message and a plain message body, we check if the first field
+         * of the first line (':' separated) does not contain a space then it _should_ be a header, and we will
+         * process all lines before a blank line as headers.
+         */
+
+        $field = substr($lines[0], 0, strpos($lines[0], ':'));
+        $in_headers = false;
+        if (!empty($field) && strpos($field, ' ') === false) {
+            $in_headers = true;
+        }
+
+        foreach ($lines as $line) {
+            $lines_out = [];
+            if ($in_headers && $line === '') {
+                $in_headers = false;
+            }
+            //Break this line up into several smaller lines if it's too long
+            //Micro-optimisation: isset($str[$len]) is faster than (strlen($str) > $len),
+            while (isset($line[self::MAX_LINE_LENGTH])) {
+                //Working backwards, try to find a space within the last MAX_LINE_LENGTH chars of the line to break on
+                //so as to avoid breaking in the middle of a word
+                $pos = strrpos(substr($line, 0, self::MAX_LINE_LENGTH), ' ');
+                //Deliberately matches both false and 0
+                if (!$pos) {
+                    //No nice break found, add a hard break
+                    $pos = self::MAX_LINE_LENGTH - 1;
+                    $lines_out[] = substr($line, 0, $pos);
+                    $line = substr($line, $pos);
+                } else {
+                    //Break at the found point
+                    $lines_out[] = substr($line, 0, $pos);
+                    //Move along by the amount we dealt with
+                    $line = substr($line, $pos + 1);
+                }
+                //If processing headers add a LWSP-char to the front of new line RFC822 section 3.1.1
+                if ($in_headers) {
+                    $line = "\t" . $line;
+                }
+            }
+            $lines_out[] = $line;
+
+            //Send the lines to the server
+            foreach ($lines_out as $line_out) {
+                //Dot-stuffing as per RFC5321 section 4.5.2
+                //https://tools.ietf.org/html/rfc5321#section-4.5.2
+                if (!empty($line_out) && $line_out[0] === '.') {
+                    $line_out = '.' . $line_out;
+                }
+                $this->client_send($line_out . static::LE, 'DATA');
+            }
+        }
+
+        //Message data has been sent, complete the command
+        //Increase timelimit for end of DATA command
+        $savetimelimit = $this->Timelimit;
+        $this->Timelimit *= 2;
+        $result = $this->sendCommand('DATA END', '.', 250);
+        $this->recordLastTransactionID();
+        //Restore timelimit
+        $this->Timelimit = $savetimelimit;
+
+        return $result;
+    }
+
+    /**
+     * Send an SMTP HELO or EHLO command.
+     * Used to identify the sending server to the receiving server.
+     * This makes sure that client and server are in a known state.
+     * Implements RFC 821: HELO <SP> <domain> <CRLF>
+     * and RFC 2821 EHLO.
+     *
+     * @param string $host The host name or IP to connect to
+     *
+     * @return bool
+     */
+    public function hello($host = '')
+    {
+        //Try extended hello first (RFC 2821)
+        if ($this->sendHello('EHLO', $host)) {
+            return true;
+        }
+
+        //Some servers shut down the SMTP service here (RFC 5321)
+        if (substr($this->helo_rply, 0, 3) == '421') {
+            return false;
+        }
+
+        return $this->sendHello('HELO', $host);
+    }
+
+    /**
+     * Send an SMTP HELO or EHLO command.
+     * Low-level implementation used by hello().
+     *
+     * @param string $hello The HELO string
+     * @param string $host  The hostname to say we are
+     *
+     * @return bool
+     *
+     * @see hello()
+     */
+    protected function sendHello($hello, $host)
+    {
+        $noerror = $this->sendCommand($hello, $hello . ' ' . $host, 250);
+        $this->helo_rply = $this->last_reply;
+        if ($noerror) {
+            $this->parseHelloFields($hello);
+        } else {
+            $this->server_caps = null;
+        }
+
+        return $noerror;
+    }
+
+    /**
+     * Parse a reply to HELO/EHLO command to discover server extensions.
+     * In case of HELO, the only parameter that can be discovered is a server name.
+     *
+     * @param string $type `HELO` or `EHLO`
+     */
+    protected function parseHelloFields($type)
+    {
+        $this->server_caps = [];
+        $lines = explode("\n", $this->helo_rply);
+
+        foreach ($lines as $n => $s) {
+            //First 4 chars contain response code followed by - or space
+            $s = trim(substr($s, 4));
+            if (empty($s)) {
+                continue;
+            }
+            $fields = explode(' ', $s);
+            if (!empty($fields)) {
+                if (!$n) {
+                    $name = $type;
+                    $fields = $fields[0];
+                } else {
+                    $name = array_shift($fields);
+                    switch ($name) {
+                        case 'SIZE':
+                            $fields = ($fields ? $fields[0] : 0);
+                            break;
+                        case 'AUTH':
+                            if (!is_array($fields)) {
+                                $fields = [];
+                            }
+                            break;
+                        default:
+                            $fields = true;
+                    }
+                }
+                $this->server_caps[$name] = $fields;
+            }
+        }
+    }
+
+    /**
+     * Send an SMTP MAIL command.
+     * Starts a mail transaction from the email address specified in
+     * $from. Returns true if successful or false otherwise. If True
+     * the mail transaction is started and then one or more recipient
+     * commands may be called followed by a data command.
+     * Implements RFC 821: MAIL <SP> FROM:<reverse-path> <CRLF>.
+     *
+     * @param string $from Source address of this message
+     *
+     * @return bool
+     */
+    public function mail($from)
+    {
+        $useVerp = ($this->do_verp ? ' XVERP' : '');
+
+        return $this->sendCommand(
+            'MAIL FROM',
+            'MAIL FROM:<' . $from . '>' . $useVerp,
+            250
+        );
+    }
+
+    /**
+     * Send an SMTP QUIT command.
+     * Closes the socket if there is no error or the $close_on_error argument is true.
+     * Implements from RFC 821: QUIT <CRLF>.
+     *
+     * @param bool $close_on_error Should the connection close if an error occurs?
+     *
+     * @return bool
+     */
+    public function quit($close_on_error = true)
+    {
+        $noerror = $this->sendCommand('QUIT', 'QUIT', 221);
+        $err = $this->error; //Save any error
+        if ($noerror || $close_on_error) {
+            $this->close();
+            $this->error = $err; //Restore any error from the quit command
+        }
+
+        return $noerror;
+    }
+
+    /**
+     * Send an SMTP RCPT command.
+     * Sets the TO argument to $toaddr.
+     * Returns true if the recipient was accepted false if it was rejected.
+     * Implements from RFC 821: RCPT <SP> TO:<forward-path> <CRLF>.
+     *
+     * @param string $address The address the message is being sent to
+     * @param string $dsn     Comma separated list of DSN notifications. NEVER, SUCCESS, FAILURE
+     *                        or DELAY. If you specify NEVER all other notifications are ignored.
+     *
+     * @return bool
+     */
+    public function recipient($address, $dsn = '')
+    {
+        if (empty($dsn)) {
+            $rcpt = 'RCPT TO:<' . $address . '>';
+        } else {
+            $dsn = strtoupper($dsn);
+            $notify = [];
+
+            if (strpos($dsn, 'NEVER') !== false) {
+                $notify[] = 'NEVER';
+            } else {
+                foreach (['SUCCESS', 'FAILURE', 'DELAY'] as $value) {
+                    if (strpos($dsn, $value) !== false) {
+                        $notify[] = $value;
+                    }
+                }
+            }
+
+            $rcpt = 'RCPT TO:<' . $address . '> NOTIFY=' . implode(',', $notify);
+        }
+
+        return $this->sendCommand(
+            'RCPT TO',
+            $rcpt,
+            [250, 251]
+        );
+    }
+
+    /**
+     * Send an SMTP RSET command.
+     * Abort any transaction that is currently in progress.
+     * Implements RFC 821: RSET <CRLF>.
+     *
+     * @return bool True on success
+     */
+    public function reset()
+    {
+        return $this->sendCommand('RSET', 'RSET', 250);
+    }
+
+    /**
+     * Send a command to an SMTP server and check its return code.
+     *
+     * @param string    $command       The command name - not sent to the server
+     * @param string    $commandstring The actual command to send
+     * @param int|array $expect        One or more expected integer success codes
+     *
+     * @return bool True on success
+     */
+    protected function sendCommand($command, $commandstring, $expect)
+    {
+        if (!$this->connected()) {
+            $this->setError("Called $command without being connected");
+
+            return false;
+        }
+        //Reject line breaks in all commands
+        if ((strpos($commandstring, "\n") !== false) || (strpos($commandstring, "\r") !== false)) {
+            $this->setError("Command '$command' contained line breaks");
+
+            return false;
+        }
+        $this->client_send($commandstring . static::LE, $command);
+
+        $this->last_reply = $this->get_lines();
+        //Fetch SMTP code and possible error code explanation
+        $matches = [];
+        if (preg_match('/^([\d]{3})[ -](?:([\d]\\.[\d]\\.[\d]{1,2}) )?/', $this->last_reply, $matches)) {
+            $code = (int) $matches[1];
+            $code_ex = (count($matches) > 2 ? $matches[2] : null);
+            //Cut off error code from each response line
+            $detail = preg_replace(
+                "/{$code}[ -]" .
+                ($code_ex ? str_replace('.', '\\.', $code_ex) . ' ' : '') . '/m',
+                '',
+                $this->last_reply
+            );
+        } else {
+            //Fall back to simple parsing if regex fails
+            $code = (int) substr($this->last_reply, 0, 3);
+            $code_ex = null;
+            $detail = substr($this->last_reply, 4);
+        }
+
+        $this->edebug('SERVER -> CLIENT: ' . $this->last_reply, self::DEBUG_SERVER);
+
+        if (!in_array($code, (array) $expect, true)) {
+            $this->setError(
+                "$command command failed",
+                $detail,
+                $code,
+                $code_ex
+            );
+            $this->edebug(
+                'SMTP ERROR: ' . $this->error['error'] . ': ' . $this->last_reply,
+                self::DEBUG_CLIENT
+            );
+
+            return false;
+        }
+
+        //Don't clear the error store when using keepalive
+        if ($command !== 'RSET') {
+            $this->setError('');
+        }
+
+        return true;
+    }
+
+    /**
+     * Send an SMTP SAML command.
+     * Starts a mail transaction from the email address specified in $from.
+     * Returns true if successful or false otherwise. If True
+     * the mail transaction is started and then one or more recipient
+     * commands may be called followed by a data command. This command
+     * will send the message to the users terminal if they are logged
+     * in and send them an email.
+     * Implements RFC 821: SAML <SP> FROM:<reverse-path> <CRLF>.
+     *
+     * @param string $from The address the message is from
+     *
+     * @return bool
+     */
+    public function sendAndMail($from)
+    {
+        return $this->sendCommand('SAML', "SAML FROM:$from", 250);
+    }
+
+    /**
+     * Send an SMTP VRFY command.
+     *
+     * @param string $name The name to verify
+     *
+     * @return bool
+     */
+    public function verify($name)
+    {
+        return $this->sendCommand('VRFY', "VRFY $name", [250, 251]);
+    }
+
+    /**
+     * Send an SMTP NOOP command.
+     * Used to keep keep-alives alive, doesn't actually do anything.
+     *
+     * @return bool
+     */
+    public function noop()
+    {
+        return $this->sendCommand('NOOP', 'NOOP', 250);
+    }
+
+    /**
+     * Send an SMTP TURN command.
+     * This is an optional command for SMTP that this class does not support.
+     * This method is here to make the RFC821 Definition complete for this class
+     * and _may_ be implemented in future.
+     * Implements from RFC 821: TURN <CRLF>.
+     *
+     * @return bool
+     */
+    public function turn()
+    {
+        $this->setError('The SMTP TURN command is not implemented');
+        $this->edebug('SMTP NOTICE: ' . $this->error['error'], self::DEBUG_CLIENT);
+
+        return false;
+    }
+
+    /**
+     * Send raw data to the server.
+     *
+     * @param string $data    The data to send
+     * @param string $command Optionally, the command this is part of, used only for controlling debug output
+     *
+     * @return int|bool The number of bytes sent to the server or false on error
+     */
+    public function client_send($data, $command = '')
+    {
+        //If SMTP transcripts are left enabled, or debug output is posted online
+        //it can leak credentials, so hide credentials in all but lowest level
+        if (
+            self::DEBUG_LOWLEVEL > $this->do_debug &&
+            in_array($command, ['User & Password', 'Username', 'Password'], true)
+        ) {
+            $this->edebug('CLIENT -> SERVER: [credentials hidden]', self::DEBUG_CLIENT);
+        } else {
+            $this->edebug('CLIENT -> SERVER: ' . $data, self::DEBUG_CLIENT);
+        }
+        set_error_handler([$this, 'errorHandler']);
+        $result = fwrite($this->smtp_conn, $data);
+        restore_error_handler();
+
+        return $result;
+    }
+
+    /**
+     * Get the latest error.
+     *
+     * @return array
+     */
+    public function getError()
+    {
+        return $this->error;
+    }
+
+    /**
+     * Get SMTP extensions available on the server.
+     *
+     * @return array|null
+     */
+    public function getServerExtList()
+    {
+        return $this->server_caps;
+    }
+
+    /**
+     * Get metadata about the SMTP server from its HELO/EHLO response.
+     * The method works in three ways, dependent on argument value and current state:
+     *   1. HELO/EHLO has not been sent - returns null and populates $this->error.
+     *   2. HELO has been sent -
+     *     $name == 'HELO': returns server name
+     *     $name == 'EHLO': returns boolean false
+     *     $name == any other string: returns null and populates $this->error
+     *   3. EHLO has been sent -
+     *     $name == 'HELO'|'EHLO': returns the server name
+     *     $name == any other string: if extension $name exists, returns True
+     *       or its options (e.g. AUTH mechanisms supported). Otherwise returns False.
+     *
+     * @param string $name Name of SMTP extension or 'HELO'|'EHLO'
+     *
+     * @return string|bool|null
+     */
+    public function getServerExt($name)
+    {
+        if (!$this->server_caps) {
+            $this->setError('No HELO/EHLO was sent');
+
+            return null;
+        }
+
+        if (!array_key_exists($name, $this->server_caps)) {
+            if ('HELO' === $name) {
+                return $this->server_caps['EHLO'];
+            }
+            if ('EHLO' === $name || array_key_exists('EHLO', $this->server_caps)) {
+                return false;
+            }
+            $this->setError('HELO handshake was used; No information about server extensions available');
+
+            return null;
+        }
+
+        return $this->server_caps[$name];
+    }
+
+    /**
+     * Get the last reply from the server.
+     *
+     * @return string
+     */
+    public function getLastReply()
+    {
+        return $this->last_reply;
+    }
+
+    /**
+     * Read the SMTP server's response.
+     * Either before eof or socket timeout occurs on the operation.
+     * With SMTP we can tell if we have more lines to read if the
+     * 4th character is '-' symbol. If it is a space then we don't
+     * need to read anything else.
+     *
+     * @return string
+     */
+    protected function get_lines()
+    {
+        //If the connection is bad, give up straight away
+        if (!is_resource($this->smtp_conn)) {
+            return '';
+        }
+        $data = '';
+        $endtime = 0;
+        stream_set_timeout($this->smtp_conn, $this->Timeout);
+        if ($this->Timelimit > 0) {
+            $endtime = time() + $this->Timelimit;
+        }
+        $selR = [$this->smtp_conn];
+        $selW = null;
+        while (is_resource($this->smtp_conn) && !feof($this->smtp_conn)) {
+            //Must pass vars in here as params are by reference
+            //solution for signals inspired by https://github.com/symfony/symfony/pull/6540
+            set_error_handler([$this, 'errorHandler']);
+            $n = stream_select($selR, $selW, $selW, $this->Timelimit);
+            restore_error_handler();
+
+            if ($n === false) {
+                $message = $this->getError()['detail'];
+
+                $this->edebug(
+                    'SMTP -> get_lines(): select failed (' . $message . ')',
+                    self::DEBUG_LOWLEVEL
+                );
+
+                //stream_select returns false when the `select` system call is interrupted
+                //by an incoming signal, try the select again
+                if (stripos($message, 'interrupted system call') !== false) {
+                    $this->edebug(
+                        'SMTP -> get_lines(): retrying stream_select',
+                        self::DEBUG_LOWLEVEL
+                    );
+                    $this->setError('');
+                    continue;
+                }
+
+                break;
+            }
+
+            if (!$n) {
+                $this->edebug(
+                    'SMTP -> get_lines(): select timed-out in (' . $this->Timelimit . ' sec)',
+                    self::DEBUG_LOWLEVEL
+                );
+                break;
+            }
+
+            //Deliberate noise suppression - errors are handled afterwards
+            $str = @fgets($this->smtp_conn, self::MAX_REPLY_LENGTH);
+            $this->edebug('SMTP INBOUND: "' . trim($str) . '"', self::DEBUG_LOWLEVEL);
+            $data .= $str;
+            //If response is only 3 chars (not valid, but RFC5321 S4.2 says it must be handled),
+            //or 4th character is a space or a line break char, we are done reading, break the loop.
+            //String array access is a significant micro-optimisation over strlen
+            if (!isset($str[3]) || $str[3] === ' ' || $str[3] === "\r" || $str[3] === "\n") {
+                break;
+            }
+            //Timed-out? Log and break
+            $info = stream_get_meta_data($this->smtp_conn);
+            if ($info['timed_out']) {
+                $this->edebug(
+                    'SMTP -> get_lines(): stream timed-out (' . $this->Timeout . ' sec)',
+                    self::DEBUG_LOWLEVEL
+                );
+                break;
+            }
+            //Now check if reads took too long
+            if ($endtime && time() > $endtime) {
+                $this->edebug(
+                    'SMTP -> get_lines(): timelimit reached (' .
+                    $this->Timelimit . ' sec)',
+                    self::DEBUG_LOWLEVEL
+                );
+                break;
+            }
+        }
+
+        return $data;
+    }
+
+    /**
+     * Enable or disable VERP address generation.
+     *
+     * @param bool $enabled
+     */
+    public function setVerp($enabled = false)
+    {
+        $this->do_verp = $enabled;
+    }
+
+    /**
+     * Get VERP address generation mode.
+     *
+     * @return bool
+     */
+    public function getVerp()
+    {
+        return $this->do_verp;
+    }
+
+    /**
+     * Set error messages and codes.
+     *
+     * @param string $message      The error message
+     * @param string $detail       Further detail on the error
+     * @param string $smtp_code    An associated SMTP error code
+     * @param string $smtp_code_ex Extended SMTP code
+     */
+    protected function setError($message, $detail = '', $smtp_code = '', $smtp_code_ex = '')
+    {
+        $this->error = [
+            'error' => $message,
+            'detail' => $detail,
+            'smtp_code' => $smtp_code,
+            'smtp_code_ex' => $smtp_code_ex,
+        ];
+    }
+
+    /**
+     * Set debug output method.
+     *
+     * @param string|callable $method The name of the mechanism to use for debugging output, or a callable to handle it
+     */
+    public function setDebugOutput($method = 'echo')
+    {
+        $this->Debugoutput = $method;
+    }
+
+    /**
+     * Get debug output method.
+     *
+     * @return string
+     */
+    public function getDebugOutput()
+    {
+        return $this->Debugoutput;
+    }
+
+    /**
+     * Set debug output level.
+     *
+     * @param int $level
+     */
+    public function setDebugLevel($level = 0)
+    {
+        $this->do_debug = $level;
+    }
+
+    /**
+     * Get debug output level.
+     *
+     * @return int
+     */
+    public function getDebugLevel()
+    {
+        return $this->do_debug;
+    }
+
+    /**
+     * Set SMTP timeout.
+     *
+     * @param int $timeout The timeout duration in seconds
+     */
+    public function setTimeout($timeout = 0)
+    {
+        $this->Timeout = $timeout;
+    }
+
+    /**
+     * Get SMTP timeout.
+     *
+     * @return int
+     */
+    public function getTimeout()
+    {
+        return $this->Timeout;
+    }
+
+    /**
+     * Reports an error number and string.
+     *
+     * @param int    $errno   The error number returned by PHP
+     * @param string $errmsg  The error message returned by PHP
+     * @param string $errfile The file the error occurred in
+     * @param int    $errline The line number the error occurred on
+     */
+    protected function errorHandler($errno, $errmsg, $errfile = '', $errline = 0)
+    {
+        $notice = 'Connection failed.';
+        $this->setError(
+            $notice,
+            $errmsg,
+            (string) $errno
+        );
+        $this->edebug(
+            "$notice Error #$errno: $errmsg [$errfile line $errline]",
+            self::DEBUG_CONNECTION
+        );
+    }
+
+    /**
+     * Extract and return the ID of the last SMTP transaction based on
+     * a list of patterns provided in SMTP::$smtp_transaction_id_patterns.
+     * Relies on the host providing the ID in response to a DATA command.
+     * If no reply has been received yet, it will return null.
+     * If no pattern was matched, it will return false.
+     *
+     * @return bool|string|null
+     */
+    protected function recordLastTransactionID()
+    {
+        $reply = $this->getLastReply();
+
+        if (empty($reply)) {
+            $this->last_smtp_transaction_id = null;
+        } else {
+            $this->last_smtp_transaction_id = false;
+            foreach ($this->smtp_transaction_id_patterns as $smtp_transaction_id_pattern) {
+                $matches = [];
+                if (preg_match($smtp_transaction_id_pattern, $reply, $matches)) {
+                    $this->last_smtp_transaction_id = trim($matches[1]);
+                    break;
+                }
+            }
+        }
+
+        return $this->last_smtp_transaction_id;
+    }
+
+    /**
+     * Get the queue/transaction ID of the last SMTP transaction
+     * If no reply has been received yet, it will return null.
+     * If no pattern was matched, it will return false.
+     *
+     * @return bool|string|null
+     *
+     * @see recordLastTransactionID()
+     */
+    public function getLastTransactionID()
+    {
+        return $this->last_smtp_transaction_id;
+    }
+}