ru-se.com

PHPMailer.php (172583B)

---

 <?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 = 'root@localhost';
 
     /**
      * The From name of the message.
      *
      * @var string
      */
     public $FromName = 'Root User';
 
     /**
      * 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 auth type.
      * Options are CRAM-MD5, LOGIN, PLAIN, XOAUTH2, attempted in that order if not specified.
      *
      * @var string
      */
     public $AuthType = '';
 
     /**
      * An instance of the PHPMailer OAuth class.
      *
      * @var OAuth
      */
     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 languages.
      *
      * @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 = '6.5.0';
 
     /**
      * 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 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 (ini_get('mbstring.func_overload') & 1) { // phpcs:ignore PHPCompatibility.IniDirectives.RemovedIniDirectives.mbstring_func_overloadDeprecated
             $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 to send, resp. to reply to
      * @param string $name
      *
      * @throws Exception
      *
      * @return bool true on success, false if address already used or invalid in some way
      */
     protected function addOrEnqueueAnAddress($kind, $address, $name)
     {
         $address = trim($address);
         $name = trim(preg_replace('/[\r\n]+/', '', $name)); //Strip breaks and trim
         $pos = strrpos($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;
         }
         $params = [$kind, $address, $name];
         //Enqueue addresses with IDN until we know the PHPMailer::$CharSet.
         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);
     }
 
     /**
      * 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   $useimap Whether to use the IMAP extension to parse the list
      *
      * @return array
      */
     public static function parseAddresses($addrstr, $useimap = true)
     {
         $addresses = [];
         if ($useimap && function_exists('imap_rfc822_parse_adrlist')) {
             //Use this built-in parser if it's available
             $list = imap_rfc822_parse_adrlist($addrstr, '');
             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') &&
                         extension_loaded('mbstring') &&
                         preg_match('/^=\?.*\?=$/', $address->personal)
                     ) {
                         $address->personal = mb_decode_mimeheader($address->personal);
                     }
 
                     $addresses[] = [
                         'name' => (property_exists($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($email)) {
                         //If this name is encoded, decode it
                         if (preg_match('/^=\?.*\?=$/', $name)) {
                             $name = mb_decode_mimeheader($name);
                         }
                         $addresses[] = [
                             //Remove any surrounding quotes and spaces from the name
                             'name' => trim($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)
     {
         $address = trim($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, $errorcode, \INTL_IDNA_VARIANT_UTS46);
                 } elseif (defined('INTL_IDNA_VARIANT_2003')) {
                     //Fall back to this old, deprecated/removed encoding
                     // phpcs:ignore PHPCompatibility.Constants.RemovedConstants.intl_idna_variant_2003Deprecated
                     $punycode = idn_to_ascii($domain, $errorcode, \INTL_IDNA_VARIANT_2003);
                 } else {
                     //Fall back to a default we don't know about
                     // phpcs:ignore PHPCompatibility.ParameterValues.NewIDNVariantDefault.NotSet
                     $punycode = idn_to_ascii($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(
                 '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+.',
                 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 $exc) {
             if ($this->Mailer === 'smtp' && $this->SMTPKeepAlive == true) {
                 $this->smtp->reset();
             }
             $this->setError($exc->getMessage());
             $this->edebug($exc->getMessage());
             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
         if (empty($this->Sender) && !empty(ini_get('sendmail_from'))) {
             //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);
                 $this->doCallback(
                     ($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)
     {
         //Future-proof
         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;
         }
         $readable = file_exists($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 = implode(', ', $toArr);
 
         $params = null;
         //This sets the SMTP envelope sender which gets turned into a return-path header by the receiver
         //A space after `-f` is optional, but there is a long history of its presence
         //causing problems, so we don't use one
         //Exim docs: http://www.exim.org/exim-html-current/doc/html/spec_html/ch-the_exim_command_line.html
         //Sendmail docs: http://www.sendmail.org/~ca/email/man/sendmail.html
         //Qmail docs: http://www.qmail.org/man/man8/qmail-inject.html
         //Example problem: https://www.drupal.org/node/1057954
         //CVE-2016-10033, CVE-2016-10045: Don't pass -f if characters will be escaped.
         if (empty($this->Sender) && !empty(ini_get('sendmail_from'))) {
             //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);
                 $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);
         $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 (!$this->smtp->startTLS()) {
                             throw new Exception($this->lang('connect_host'));
                         }
                         //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;
         }
 
         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.
      * Returns false if it cannot load the language file.
      * The default language is English.
      *
      * @param string $langcode  ISO 639-1 2-character language code (e.g. French is "fr")
      * @param string $lang_path Path to the language file directory, with trailing separator (slash).D
      *                          Do not set this from user input!
      *
      * @return bool
      */
     public function setLanguage($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
         $PHPMAILER_LANG = [
             'authenticate' => 'SMTP Error: Could not authenticate.',
             'connect_host' => 'SMTP Error: Could not connect to SMTP host.',
             'data_not_accepted' => 'SMTP Error: data not accepted.',
             'empty_message' => 'Message body empty',
             'encoding' => 'Unknown encoding: ',
             'execute' => 'Could not execute: ',
             'file_access' => 'Could not access file: ',
             'file_open' => 'File Error: Could not open file: ',
             'from_failed' => 'The following From address failed: ',
             'instantiate' => 'Could not instantiate mail function.',
             'invalid_address' => 'Invalid address: ',
             'invalid_hostentry' => 'Invalid hostentry: ',
             'invalid_host' => 'Invalid host: ',
             'mailer_not_supported' => ' mailer is not supported.',
             'provide_address' => 'You must provide at least one recipient email address.',
             'recipients_failed' => 'SMTP Error: The following recipients failed: ',
             'signing' => 'Signing Error: ',
             'smtp_connect_failed' => 'SMTP connect() failed.',
             'smtp_error' => 'SMTP server error: ',
             'variable_set' => 'Cannot set or reset variable: ',
             'extension_missing' => 'Extension missing: ',
         ];
         if (empty($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 $langcode
         if (!preg_match('/^[a-z]{2}(?:_[a-zA-Z]{2})?$/', $langcode)) {
             $langcode = 'en';
         }
         $foundlang = true;
         $lang_file = $lang_path . 'phpmailer.lang-' . $langcode . '.php';
         //There is no English translation file
         if ('en' !== $langcode) {
             //Make sure language file path is readable
             if (!static::fileIsAccessible($lang_file)) {
                 $foundlang = false;
             } else {
                 //$foundlang = include $lang_file;
                 $lines = file($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()
     {
         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 (empty($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 ('' !== $this->MessageID && preg_match('/^<.*@.*>$/', $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) {
             $result .= $this->headerLine(
                 'X-Mailer',
                 'PHPMailer ' . self::VERSION . ' (https://github.com/PHPMailer/PHPMailer)'
             );
         } else {
             $myXmailer = trim($this->XMailer);
             if ($myXmailer) {
                 $result .= $this->headerLine('X-Mailer', $myXmailer);
             }
         }
 
         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->uniqueid = $this->generateId();
         $this->boundary[1] = 'b1_' . $this->uniqueid;
         $this->boundary[2] = 'b2_' . $this->uniqueid;
         $this->boundary[3] = 'b3_' . $this->uniqueid;
 
         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
         $mimepre = 'This is a multi-part message in MIME format.' . static::$LE . static::$LE;
         switch ($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;
     }
 
     /**
      * 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.
      * 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 name
      * @param string $encoding    File encoding (see $Encoding)
      * @param string $type        File MIME type
      * @param string $disposition Disposition to use
      *
      * @throws Exception
      *
      * @return bool True on successfully adding an attachment
      */
     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 .= ' Detail: ' . $lasterror['detail'];
                 }
                 if (!empty($lasterror['smtp_code'])) {
                     $msg .= ' SMTP code: ' . $lasterror['smtp_code'];
                 }
                 if (!empty($lasterror['smtp_code_ex'])) {
                     $msg .= ' Additional SMTP info: ' . $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;
         }
         if (filter_var('http://' . $host, FILTER_VALIDATE_URL) !== false) {
             //Is it a syntactically valid hostname?
             return true;
         }
 
         return 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;
     }
 
     /**
      * 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 $value Header value
      *
      * @throws Exception
      */
     public function addCustomHeader($name, $value = null)
     {
         if (null === $value && strpos($name, ':') !== false) {
             //Value passed in as name:value
             list($name, $value) = explode(':', $name, 2);
         }
         $name = trim($name);
         $value = trim($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('Invalid header name or value');
             }
 
             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 $advanced Any boolean value to use the internal converter,
      *                                or provide your own callable for custom conversion
      *
      * @return string
      */
     public function html2text($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',
             '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 breaks from a string.
      *
      * @param string $text
      *
      * @return string The text to remove breaks from
      */
     public static function stripTrailingWSP($text)
     {
         return rtrim($text, " \r\n\t");
     }
 
     /**
      * 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::stripTrailingWSP($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 OAuth instance.
      *
      * @return OAuth
      */
     public function getOAuth()
     {
         return $this->oauth;
     }
 
     /**
      * Set an OAuth instance.
      */
     public function setOAuth(OAuth $oauth)
     {
         $this->oauth = $oauth;
     }
 }