first commit

include/swiftmailer/lib/classes/Swift/Mime/Attachment.php

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+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * An attachment, in a multipart message.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Attachment extends Swift_Mime_SimpleMimeEntity
+{
+    /** Recognized MIME types */
+    private $mimeTypes = [];
+
+    /**
+     * Create a new Attachment with $headers, $encoder and $cache.
+     *
+     * @param array $mimeTypes
+     */
+    public function __construct(Swift_Mime_SimpleHeaderSet $headers, Swift_Mime_ContentEncoder $encoder, Swift_KeyCache $cache, Swift_IdGenerator $idGenerator, $mimeTypes = [])
+    {
+        parent::__construct($headers, $encoder, $cache, $idGenerator);
+        $this->setDisposition('attachment');
+        $this->setContentType('application/octet-stream');
+        $this->mimeTypes = $mimeTypes;
+    }
+
+    /**
+     * Get the nesting level used for this attachment.
+     *
+     * Always returns {@link LEVEL_MIXED}.
+     *
+     * @return int
+     */
+    public function getNestingLevel()
+    {
+        return self::LEVEL_MIXED;
+    }
+
+    /**
+     * Get the Content-Disposition of this attachment.
+     *
+     * By default attachments have a disposition of "attachment".
+     *
+     * @return string
+     */
+    public function getDisposition()
+    {
+        return $this->getHeaderFieldModel('Content-Disposition');
+    }
+
+    /**
+     * Set the Content-Disposition of this attachment.
+     *
+     * @param string $disposition
+     *
+     * @return $this
+     */
+    public function setDisposition($disposition)
+    {
+        if (!$this->setHeaderFieldModel('Content-Disposition', $disposition)) {
+            $this->getHeaders()->addParameterizedHeader('Content-Disposition', $disposition);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the filename of this attachment when downloaded.
+     *
+     * @return string
+     */
+    public function getFilename()
+    {
+        return $this->getHeaderParameter('Content-Disposition', 'filename');
+    }
+
+    /**
+     * Set the filename of this attachment.
+     *
+     * @param string $filename
+     *
+     * @return $this
+     */
+    public function setFilename($filename)
+    {
+        $this->setHeaderParameter('Content-Disposition', 'filename', $filename);
+        $this->setHeaderParameter('Content-Type', 'name', $filename);
+
+        return $this;
+    }
+
+    /**
+     * Get the file size of this attachment.
+     *
+     * @return int
+     */
+    public function getSize()
+    {
+        return $this->getHeaderParameter('Content-Disposition', 'size');
+    }
+
+    /**
+     * Set the file size of this attachment.
+     *
+     * @param int $size
+     *
+     * @return $this
+     */
+    public function setSize($size)
+    {
+        $this->setHeaderParameter('Content-Disposition', 'size', $size);
+
+        return $this;
+    }
+
+    /**
+     * Set the file that this attachment is for.
+     *
+     * @param string $contentType optional
+     *
+     * @return $this
+     */
+    public function setFile(Swift_FileStream $file, $contentType = null)
+    {
+        $this->setFilename(basename($file->getPath()));
+        $this->setBody($file, $contentType);
+        if (!isset($contentType)) {
+            $extension = strtolower(substr($file->getPath(), strrpos($file->getPath(), '.') + 1));
+
+            if (\array_key_exists($extension, $this->mimeTypes)) {
+                $this->setContentType($this->mimeTypes[$extension]);
+            }
+        }
+
+        return $this;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/CharsetObserver.php

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+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Observes changes in an Mime entity's character set.
+ *
+ * @author Chris Corbyn
+ */
+interface Swift_Mime_CharsetObserver
+{
+    /**
+     * Notify this observer that the entity's charset has changed.
+     *
+     * @param string $charset
+     */
+    public function charsetChanged($charset);
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder.php

@@ -0,0 +1,34 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Interface for all Transfer Encoding schemes.
+ *
+ * @author Chris Corbyn
+ */
+interface Swift_Mime_ContentEncoder extends Swift_Encoder
+{
+    /**
+     * Encode $in to $out.
+     *
+     * @param Swift_OutputByteStream $os              to read from
+     * @param Swift_InputByteStream  $is              to write to
+     * @param int                    $firstLineOffset
+     * @param int                    $maxLineLength   - 0 indicates the default length for this encoding
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0);
+
+    /**
+     * Get the MIME name of this content encoding scheme.
+     *
+     * @return string
+     */
+    public function getName();
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/Base64ContentEncoder.php

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+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles Base 64 Transfer Encoding in Swift Mailer.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_ContentEncoder_Base64ContentEncoder extends Swift_Encoder_Base64Encoder implements Swift_Mime_ContentEncoder
+{
+    /**
+     * Encode stream $in to stream $out.
+     *
+     * @param int $firstLineOffset
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        if (0 >= $maxLineLength || 76 < $maxLineLength) {
+            $maxLineLength = 76;
+        }
+
+        $remainder = 0;
+        $base64ReadBufferRemainderBytes = null;
+
+        // To reduce memory usage, the output buffer is streamed to the input buffer like so:
+        //   Output Stream => base64encode => wrap line length => Input Stream
+        // HOWEVER it's important to note that base64_encode() should only be passed whole triplets of data (except for the final chunk of data)
+        // otherwise it will assume the input data has *ended* and it will incorrectly pad/terminate the base64 data mid-stream.
+        // We use $base64ReadBufferRemainderBytes to carry over 1-2 "remainder" bytes from the each chunk from OutputStream and pre-pend those onto the
+        // chunk of bytes read in the next iteration.
+        // When the OutputStream is empty, we must flush any remainder bytes.
+        while (true) {
+            $readBytes = $os->read(8192);
+            $atEOF = (false === $readBytes);
+
+            if ($atEOF) {
+                $streamTheseBytes = $base64ReadBufferRemainderBytes;
+            } else {
+                $streamTheseBytes = $base64ReadBufferRemainderBytes.$readBytes;
+            }
+            $base64ReadBufferRemainderBytes = null;
+            $bytesLength = \strlen($streamTheseBytes);
+
+            if (0 === $bytesLength) { // no data left to encode
+                break;
+            }
+
+            // if we're not on the last block of the ouput stream, make sure $streamTheseBytes ends with a complete triplet of data
+            // and carry over remainder 1-2 bytes to the next loop iteration
+            if (!$atEOF) {
+                $excessBytes = $bytesLength % 3;
+                if (0 !== $excessBytes) {
+                    $base64ReadBufferRemainderBytes = substr($streamTheseBytes, -$excessBytes);
+                    $streamTheseBytes = substr($streamTheseBytes, 0, $bytesLength - $excessBytes);
+                }
+            }
+
+            $encoded = base64_encode($streamTheseBytes);
+            $encodedTransformed = '';
+            $thisMaxLineLength = $maxLineLength - $remainder - $firstLineOffset;
+
+            while ($thisMaxLineLength < \strlen($encoded)) {
+                $encodedTransformed .= substr($encoded, 0, $thisMaxLineLength)."\r\n";
+                $firstLineOffset = 0;
+                $encoded = substr($encoded, $thisMaxLineLength);
+                $thisMaxLineLength = $maxLineLength;
+                $remainder = 0;
+            }
+
+            if (0 < $remainingLength = \strlen($encoded)) {
+                $remainder += $remainingLength;
+                $encodedTransformed .= $encoded;
+                $encoded = null;
+            }
+
+            $is->write($encodedTransformed);
+
+            if ($atEOF) {
+                break;
+            }
+        }
+    }
+
+    /**
+     * Get the name of this encoding scheme.
+     * Returns the string 'base64'.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return 'base64';
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/NativeQpContentEncoder.php

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+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles Quoted Printable (QP) Transfer Encoding in Swift Mailer using the PHP core function.
+ *
+ * @author Lars Strojny
+ */
+class Swift_Mime_ContentEncoder_NativeQpContentEncoder implements Swift_Mime_ContentEncoder
+{
+    /**
+     * @var string|null
+     */
+    private $charset;
+
+    /**
+     * @param string|null $charset
+     */
+    public function __construct($charset = null)
+    {
+        $this->charset = $charset ?: 'utf-8';
+    }
+
+    /**
+     * Notify this observer that the entity's charset has changed.
+     *
+     * @param string $charset
+     */
+    public function charsetChanged($charset)
+    {
+        $this->charset = $charset;
+    }
+
+    /**
+     * Encode $in to $out.
+     *
+     * @param Swift_OutputByteStream $os              to read from
+     * @param Swift_InputByteStream  $is              to write to
+     * @param int                    $firstLineOffset
+     * @param int                    $maxLineLength   0 indicates the default length for this encoding
+     *
+     * @throws RuntimeException
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        if ('utf-8' !== $this->charset) {
+            throw new RuntimeException(sprintf('Charset "%s" not supported. NativeQpContentEncoder only supports "utf-8"', $this->charset));
+        }
+
+        $string = '';
+
+        while (false !== $bytes = $os->read(8192)) {
+            $string .= $bytes;
+        }
+
+        $is->write($this->encodeString($string));
+    }
+
+    /**
+     * Get the MIME name of this content encoding scheme.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return 'quoted-printable';
+    }
+
+    /**
+     * Encode a given string to produce an encoded string.
+     *
+     * @param string $string
+     * @param int    $firstLineOffset if first line needs to be shorter
+     * @param int    $maxLineLength   0 indicates the default length for this encoding
+     *
+     * @throws RuntimeException
+     *
+     * @return string
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        if ('utf-8' !== $this->charset) {
+            throw new RuntimeException(sprintf('Charset "%s" not supported. NativeQpContentEncoder only supports "utf-8"', $this->charset));
+        }
+
+        return $this->standardize(quoted_printable_encode($string));
+    }
+
+    /**
+     * Make sure CRLF is correct and HT/SPACE are in valid places.
+     *
+     * @param string $string
+     *
+     * @return string
+     */
+    protected function standardize($string)
+    {
+        // transform CR or LF to CRLF
+        $string = preg_replace('~=0D(?!=0A)|(?<!=0D)=0A~', '=0D=0A', $string);
+        // transform =0D=0A to CRLF
+        $string = str_replace(["\t=0D=0A", ' =0D=0A', '=0D=0A'], ["=09\r\n", "=20\r\n", "\r\n"], $string);
+
+        switch (\ord(substr($string, -1))) {
+            case 0x09:
+                $string = substr_replace($string, '=09', -1);
+                break;
+            case 0x20:
+                $string = substr_replace($string, '=20', -1);
+                break;
+        }
+
+        return $string;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/NullContentEncoder.php

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+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles the case where the email body is already encoded and you just need specify the correct
+ * encoding without actually changing the encoding of the body.
+ *
+ * @author Jan Flora <jf@penneo.com>
+ */
+class Swift_Mime_ContentEncoder_NullContentEncoder implements Swift_Mime_ContentEncoder
+{
+    /**
+     * The name of this encoding scheme (probably 7bit or 8bit).
+     *
+     * @var string
+     */
+    private $name;
+
+    /**
+     * Creates a new NullContentEncoder with $name (probably 7bit or 8bit).
+     *
+     * @param string $name
+     */
+    public function __construct($name)
+    {
+        $this->name = $name;
+    }
+
+    /**
+     * Encode a given string to produce an encoded string.
+     *
+     * @param string $string
+     * @param int    $firstLineOffset ignored
+     * @param int    $maxLineLength   ignored
+     *
+     * @return string
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        return $string;
+    }
+
+    /**
+     * Encode stream $in to stream $out.
+     *
+     * @param int $firstLineOffset ignored
+     * @param int $maxLineLength   ignored
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        while (false !== ($bytes = $os->read(8192))) {
+            $is->write($bytes);
+        }
+    }
+
+    /**
+     * Get the name of this encoding scheme.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
+
+    /**
+     * Not used.
+     */
+    public function charsetChanged($charset)
+    {
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/PlainContentEncoder.php

@@ -0,0 +1,164 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles binary/7/8-bit Transfer Encoding in Swift Mailer.
+ *
+ * When sending 8-bit content over SMTP, you should use
+ * Swift_Transport_Esmtp_EightBitMimeHandler to enable the 8BITMIME SMTP
+ * extension.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_ContentEncoder_PlainContentEncoder implements Swift_Mime_ContentEncoder
+{
+    /**
+     * The name of this encoding scheme (probably 7bit or 8bit).
+     *
+     * @var string
+     */
+    private $name;
+
+    /**
+     * True if canonical transformations should be done.
+     *
+     * @var bool
+     */
+    private $canonical;
+
+    /**
+     * Creates a new PlainContentEncoder with $name (probably 7bit or 8bit).
+     *
+     * @param string $name
+     * @param bool   $canonical if canonicalization transformation should be done
+     */
+    public function __construct($name, $canonical = false)
+    {
+        $this->name = $name;
+        $this->canonical = $canonical;
+    }
+
+    /**
+     * Encode a given string to produce an encoded string.
+     *
+     * @param string $string
+     * @param int    $firstLineOffset ignored
+     * @param int    $maxLineLength   - 0 means no wrapping will occur
+     *
+     * @return string
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        if ($this->canonical) {
+            $string = $this->canonicalize($string);
+        }
+
+        return $this->safeWordwrap($string, $maxLineLength, "\r\n");
+    }
+
+    /**
+     * Encode stream $in to stream $out.
+     *
+     * @param int $firstLineOffset ignored
+     * @param int $maxLineLength   optional, 0 means no wrapping will occur
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        $leftOver = '';
+        while (false !== $bytes = $os->read(8192)) {
+            $toencode = $leftOver.$bytes;
+            if ($this->canonical) {
+                $toencode = $this->canonicalize($toencode);
+            }
+            $wrapped = $this->safeWordwrap($toencode, $maxLineLength, "\r\n");
+            $lastLinePos = strrpos($wrapped, "\r\n");
+            $leftOver = substr($wrapped, $lastLinePos);
+            $wrapped = substr($wrapped, 0, $lastLinePos);
+
+            $is->write($wrapped);
+        }
+        if (\strlen($leftOver)) {
+            $is->write($leftOver);
+        }
+    }
+
+    /**
+     * Get the name of this encoding scheme.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
+
+    /**
+     * Not used.
+     */
+    public function charsetChanged($charset)
+    {
+    }
+
+    /**
+     * A safer (but weaker) wordwrap for unicode.
+     *
+     * @param string $string
+     * @param int    $length
+     * @param string $le
+     *
+     * @return string
+     */
+    private function safeWordwrap($string, $length = 75, $le = "\r\n")
+    {
+        if (0 >= $length) {
+            return $string;
+        }
+
+        $originalLines = explode($le, $string);
+
+        $lines = [];
+        $lineCount = 0;
+
+        foreach ($originalLines as $originalLine) {
+            $lines[] = '';
+            $currentLine = &$lines[$lineCount++];
+
+            //$chunks = preg_split('/(?<=[\ \t,\.!\?\-&\+\/])/', $originalLine);
+            $chunks = preg_split('/(?<=\s)/', $originalLine);
+
+            foreach ($chunks as $chunk) {
+                if (0 != \strlen($currentLine)
+                    && \strlen($currentLine.$chunk) > $length) {
+                    $lines[] = '';
+                    $currentLine = &$lines[$lineCount++];
+                }
+                $currentLine .= $chunk;
+            }
+        }
+
+        return implode("\r\n", $lines);
+    }
+
+    /**
+     * Canonicalize string input (fix CRLF).
+     *
+     * @param string $string
+     *
+     * @return string
+     */
+    private function canonicalize($string)
+    {
+        return str_replace(
+            ["\r\n", "\r", "\n"],
+            ["\n", "\n", "\r\n"],
+            $string
+            );
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/QpContentEncoder.php

@@ -0,0 +1,134 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles Quoted Printable (QP) Transfer Encoding in Swift Mailer.
+ *
+ * @author     Chris Corbyn
+ */
+class Swift_Mime_ContentEncoder_QpContentEncoder extends Swift_Encoder_QpEncoder implements Swift_Mime_ContentEncoder
+{
+    protected $dotEscape;
+
+    /**
+     * Creates a new QpContentEncoder for the given CharacterStream.
+     *
+     * @param Swift_CharacterStream $charStream to use for reading characters
+     * @param Swift_StreamFilter    $filter     if canonicalization should occur
+     * @param bool                  $dotEscape  if dot stuffing workaround must be enabled
+     */
+    public function __construct(Swift_CharacterStream $charStream, Swift_StreamFilter $filter = null, $dotEscape = false)
+    {
+        $this->dotEscape = $dotEscape;
+        parent::__construct($charStream, $filter);
+    }
+
+    public function __sleep()
+    {
+        return ['charStream', 'filter', 'dotEscape'];
+    }
+
+    protected function getSafeMapShareId()
+    {
+        return static::class.($this->dotEscape ? '.dotEscape' : '');
+    }
+
+    protected function initSafeMap()
+    {
+        parent::initSafeMap();
+        if ($this->dotEscape) {
+            /* Encode . as =2e for buggy remote servers */
+            unset($this->safeMap[0x2e]);
+        }
+    }
+
+    /**
+     * Encode stream $in to stream $out.
+     *
+     * QP encoded strings have a maximum line length of 76 characters.
+     * If the first line needs to be shorter, indicate the difference with
+     * $firstLineOffset.
+     *
+     * @param Swift_OutputByteStream $os              output stream
+     * @param Swift_InputByteStream  $is              input stream
+     * @param int                    $firstLineOffset
+     * @param int                    $maxLineLength
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        if ($maxLineLength > 76 || $maxLineLength <= 0) {
+            $maxLineLength = 76;
+        }
+
+        $thisLineLength = $maxLineLength - $firstLineOffset;
+
+        $this->charStream->flushContents();
+        $this->charStream->importByteStream($os);
+
+        $currentLine = '';
+        $prepend = '';
+        $size = $lineLen = 0;
+
+        while (false !== $bytes = $this->nextSequence()) {
+            // If we're filtering the input
+            if (isset($this->filter)) {
+                // If we can't filter because we need more bytes
+                while ($this->filter->shouldBuffer($bytes)) {
+                    // Then collect bytes into the buffer
+                    if (false === $moreBytes = $this->nextSequence(1)) {
+                        break;
+                    }
+
+                    foreach ($moreBytes as $b) {
+                        $bytes[] = $b;
+                    }
+                }
+                // And filter them
+                $bytes = $this->filter->filter($bytes);
+            }
+
+            $enc = $this->encodeByteSequence($bytes, $size);
+
+            $i = strpos($enc, '=0D=0A');
+            $newLineLength = $lineLen + (false === $i ? $size : $i);
+
+            if ($currentLine && $newLineLength >= $thisLineLength) {
+                $is->write($prepend.$this->standardize($currentLine));
+                $currentLine = '';
+                $prepend = "=\r\n";
+                $thisLineLength = $maxLineLength;
+                $lineLen = 0;
+            }
+
+            $currentLine .= $enc;
+
+            if (false === $i) {
+                $lineLen += $size;
+            } else {
+                // 6 is the length of '=0D=0A'.
+                $lineLen = $size - strrpos($enc, '=0D=0A') - 6;
+            }
+        }
+        if (\strlen($currentLine)) {
+            $is->write($prepend.$this->standardize($currentLine));
+        }
+    }
+
+    /**
+     * Get the name of this encoding scheme.
+     * Returns the string 'quoted-printable'.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return 'quoted-printable';
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/QpContentEncoderProxy.php

@@ -0,0 +1,96 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Proxy for quoted-printable content encoders.
+ *
+ * Switches on the best QP encoder implementation for current charset.
+ *
+ * @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
+ */
+class Swift_Mime_ContentEncoder_QpContentEncoderProxy implements Swift_Mime_ContentEncoder
+{
+    /**
+     * @var Swift_Mime_ContentEncoder_QpContentEncoder
+     */
+    private $safeEncoder;
+
+    /**
+     * @var Swift_Mime_ContentEncoder_NativeQpContentEncoder
+     */
+    private $nativeEncoder;
+
+    /**
+     * @var string|null
+     */
+    private $charset;
+
+    /**
+     * Constructor.
+     *
+     * @param string|null $charset
+     */
+    public function __construct(Swift_Mime_ContentEncoder_QpContentEncoder $safeEncoder, Swift_Mime_ContentEncoder_NativeQpContentEncoder $nativeEncoder, $charset)
+    {
+        $this->safeEncoder = $safeEncoder;
+        $this->nativeEncoder = $nativeEncoder;
+        $this->charset = $charset;
+    }
+
+    /**
+     * Make a deep copy of object.
+     */
+    public function __clone()
+    {
+        $this->safeEncoder = clone $this->safeEncoder;
+        $this->nativeEncoder = clone $this->nativeEncoder;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function charsetChanged($charset)
+    {
+        $this->charset = $charset;
+        $this->safeEncoder->charsetChanged($charset);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        $this->getEncoder()->encodeByteStream($os, $is, $firstLineOffset, $maxLineLength);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getName()
+    {
+        return 'quoted-printable';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        return $this->getEncoder()->encodeString($string, $firstLineOffset, $maxLineLength);
+    }
+
+    /**
+     * @return Swift_Mime_ContentEncoder
+     */
+    private function getEncoder()
+    {
+        return 'utf-8' === $this->charset ? $this->nativeEncoder : $this->safeEncoder;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/ContentEncoder/RawContentEncoder.php

@@ -0,0 +1,65 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles raw Transfer Encoding in Swift Mailer.
+ *
+ * When sending 8-bit content over SMTP, you should use
+ * Swift_Transport_Esmtp_EightBitMimeHandler to enable the 8BITMIME SMTP
+ * extension.
+ *
+ * @author Sebastiaan Stok <s.stok@rollerscapes.net>
+ */
+class Swift_Mime_ContentEncoder_RawContentEncoder implements Swift_Mime_ContentEncoder
+{
+    /**
+     * Encode a given string to produce an encoded string.
+     *
+     * @param string $string
+     * @param int    $firstLineOffset ignored
+     * @param int    $maxLineLength   ignored
+     *
+     * @return string
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        return $string;
+    }
+
+    /**
+     * Encode stream $in to stream $out.
+     *
+     * @param int $firstLineOffset ignored
+     * @param int $maxLineLength   ignored
+     */
+    public function encodeByteStream(Swift_OutputByteStream $os, Swift_InputByteStream $is, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        while (false !== ($bytes = $os->read(8192))) {
+            $is->write($bytes);
+        }
+    }
+
+    /**
+     * Get the name of this encoding scheme.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return 'raw';
+    }
+
+    /**
+     * Not used.
+     */
+    public function charsetChanged($charset)
+    {
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/EmbeddedFile.php

@@ -0,0 +1,41 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * An embedded file, in a multipart message.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_EmbeddedFile extends Swift_Mime_Attachment
+{
+    /**
+     * Creates a new Attachment with $headers and $encoder.
+     *
+     * @param array $mimeTypes optional
+     */
+    public function __construct(Swift_Mime_SimpleHeaderSet $headers, Swift_Mime_ContentEncoder $encoder, Swift_KeyCache $cache, Swift_IdGenerator $idGenerator, $mimeTypes = [])
+    {
+        parent::__construct($headers, $encoder, $cache, $idGenerator, $mimeTypes);
+        $this->setDisposition('inline');
+        $this->setId($this->getId());
+    }
+
+    /**
+     * Get the nesting level of this EmbeddedFile.
+     *
+     * Returns {@see LEVEL_RELATED}.
+     *
+     * @return int
+     */
+    public function getNestingLevel()
+    {
+        return self::LEVEL_RELATED;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/EncodingObserver.php

@@ -0,0 +1,22 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Observes changes for a Mime entity's ContentEncoder.
+ *
+ * @author Chris Corbyn
+ */
+interface Swift_Mime_EncodingObserver
+{
+    /**
+     * Notify this observer that the observed entity's ContentEncoder has changed.
+     */
+    public function encoderChanged(Swift_Mime_ContentEncoder $encoder);
+}

include/swiftmailer/lib/classes/Swift/Mime/Header.php

@@ -0,0 +1,93 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * A MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+interface Swift_Mime_Header
+{
+    /** Text headers */
+    const TYPE_TEXT = 2;
+
+    /**  headers (text + params) */
+    const TYPE_PARAMETERIZED = 6;
+
+    /** Mailbox and address headers */
+    const TYPE_MAILBOX = 8;
+
+    /** Date and time headers */
+    const TYPE_DATE = 16;
+
+    /** Identification headers */
+    const TYPE_ID = 32;
+
+    /** Address path headers */
+    const TYPE_PATH = 64;
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType();
+
+    /**
+     * Set the model for the field body.
+     *
+     * The actual types needed will vary depending upon the type of Header.
+     *
+     * @param mixed $model
+     */
+    public function setFieldBodyModel($model);
+
+    /**
+     * Set the charset used when rendering the Header.
+     *
+     * @param string $charset
+     */
+    public function setCharset($charset);
+
+    /**
+     * Get the model for the field body.
+     *
+     * The return type depends on the specifics of the Header.
+     *
+     * @return mixed
+     */
+    public function getFieldBodyModel();
+
+    /**
+     * Get the name of this header (e.g. Subject).
+     *
+     * The name is an identifier and as such will be immutable.
+     *
+     * @return string
+     */
+    public function getFieldName();
+
+    /**
+     * Get the field body, prepared for folding into a final header value.
+     *
+     * @return string
+     */
+    public function getFieldBody();
+
+    /**
+     * Get this Header rendered as a compliant string, including trailing CRLF.
+     *
+     * @return string
+     */
+    public function toString();
+}

include/swiftmailer/lib/classes/Swift/Mime/HeaderEncoder.php

@@ -0,0 +1,24 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Interface for all Header Encoding schemes.
+ *
+ * @author Chris Corbyn
+ */
+interface Swift_Mime_HeaderEncoder extends Swift_Encoder
+{
+    /**
+     * Get the MIME name of this content encoding scheme.
+     *
+     * @return string
+     */
+    public function getName();
+}

include/swiftmailer/lib/classes/Swift/Mime/HeaderEncoder/Base64HeaderEncoder.php

@@ -0,0 +1,55 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles Base64 (B) Header Encoding in Swift Mailer.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_HeaderEncoder_Base64HeaderEncoder extends Swift_Encoder_Base64Encoder implements Swift_Mime_HeaderEncoder
+{
+    /**
+     * Get the name of this encoding scheme.
+     * Returns the string 'B'.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return 'B';
+    }
+
+    /**
+     * Takes an unencoded string and produces a Base64 encoded string from it.
+     *
+     * If the charset is iso-2022-jp, it uses mb_encode_mimeheader instead of
+     * default encodeString, otherwise pass to the parent method.
+     *
+     * @param string $string          string to encode
+     * @param int    $firstLineOffset
+     * @param int    $maxLineLength   optional, 0 indicates the default of 76 bytes
+     * @param string $charset
+     *
+     * @return string
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0, $charset = 'utf-8')
+    {
+        if ('iso-2022-jp' === strtolower($charset)) {
+            $old = mb_internal_encoding();
+            mb_internal_encoding('utf-8');
+            $newstring = mb_encode_mimeheader($string, $charset, $this->getName(), "\r\n");
+            mb_internal_encoding($old);
+
+            return $newstring;
+        }
+
+        return parent::encodeString($string, $firstLineOffset, $maxLineLength);
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/HeaderEncoder/QpHeaderEncoder.php

@@ -0,0 +1,65 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Handles Quoted Printable (Q) Header Encoding in Swift Mailer.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_HeaderEncoder_QpHeaderEncoder extends Swift_Encoder_QpEncoder implements Swift_Mime_HeaderEncoder
+{
+    /**
+     * Creates a new QpHeaderEncoder for the given CharacterStream.
+     *
+     * @param Swift_CharacterStream $charStream to use for reading characters
+     */
+    public function __construct(Swift_CharacterStream $charStream)
+    {
+        parent::__construct($charStream);
+    }
+
+    protected function initSafeMap()
+    {
+        foreach (array_merge(
+            range(0x61, 0x7A), range(0x41, 0x5A),
+            range(0x30, 0x39), [0x20, 0x21, 0x2A, 0x2B, 0x2D, 0x2F]
+        ) as $byte) {
+            $this->safeMap[$byte] = \chr($byte);
+        }
+    }
+
+    /**
+     * Get the name of this encoding scheme.
+     *
+     * Returns the string 'Q'.
+     *
+     * @return string
+     */
+    public function getName()
+    {
+        return 'Q';
+    }
+
+    /**
+     * Takes an unencoded string and produces a QP encoded string from it.
+     *
+     * @param string $string          string to encode
+     * @param int    $firstLineOffset optional
+     * @param int    $maxLineLength   optional, 0 indicates the default of 76 chars
+     *
+     * @return string
+     */
+    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
+    {
+        return str_replace([' ', '=20', "=\r\n"], ['_', '_', "\r\n"],
+            parent::encodeString($string, $firstLineOffset, $maxLineLength)
+        );
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/AbstractHeader.php

@@ -0,0 +1,476 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * An abstract base MIME Header.
+ *
+ * @author     Chris Corbyn
+ */
+abstract class Swift_Mime_Headers_AbstractHeader implements Swift_Mime_Header
+{
+    const PHRASE_PATTERN = '(?:(?:(?:(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?[a-zA-Z0-9!#\$%&\'\*\+\-\/=\?\^_`\{\}\|~]+(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?)|(?:(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?"((?:(?:[ \t]*(?:\r\n))?[ \t])?(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21\x23-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])))*(?:(?:[ \t]*(?:\r\n))?[ \t])?"(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))*(?:(?:(?:(?:[ \t]*(?:\r\n))?[ \t])?(\((?:(?:(?:[ \t]*(?:\r\n))?[ \t])|(?:(?:[\x01-\x08\x0B\x0C\x0E-\x19\x7F]|[\x21-\x27\x2A-\x5B\x5D-\x7E])|(?:\\[\x00-\x08\x0B\x0C\x0E-\x7F])|(?1)))*(?:(?:[ \t]*(?:\r\n))?[ \t])?\)))|(?:(?:[ \t]*(?:\r\n))?[ \t])))?))+?)';
+
+    /**
+     * The name of this Header.
+     *
+     * @var string
+     */
+    private $name;
+
+    /**
+     * The Encoder used to encode this Header.
+     *
+     * @var Swift_Encoder
+     */
+    private $encoder;
+
+    /**
+     * The maximum length of a line in the header.
+     *
+     * @var int
+     */
+    private $lineLength = 78;
+
+    /**
+     * The language used in this Header.
+     *
+     * @var string
+     */
+    private $lang;
+
+    /**
+     * The character set of the text in this Header.
+     *
+     * @var string
+     */
+    private $charset = 'utf-8';
+
+    /**
+     * The value of this Header, cached.
+     *
+     * @var string
+     */
+    private $cachedValue = null;
+
+    /**
+     * Set the character set used in this Header.
+     *
+     * @param string $charset
+     */
+    public function setCharset($charset)
+    {
+        $this->clearCachedValueIf($charset != $this->charset);
+        $this->charset = $charset;
+        if (isset($this->encoder)) {
+            $this->encoder->charsetChanged($charset);
+        }
+    }
+
+    /**
+     * Get the character set used in this Header.
+     *
+     * @return string
+     */
+    public function getCharset()
+    {
+        return $this->charset;
+    }
+
+    /**
+     * Set the language used in this Header.
+     *
+     * For example, for US English, 'en-us'.
+     * This can be unspecified.
+     *
+     * @param string $lang
+     */
+    public function setLanguage($lang)
+    {
+        $this->clearCachedValueIf($this->lang != $lang);
+        $this->lang = $lang;
+    }
+
+    /**
+     * Get the language used in this Header.
+     *
+     * @return string
+     */
+    public function getLanguage()
+    {
+        return $this->lang;
+    }
+
+    /**
+     * Set the encoder used for encoding the header.
+     */
+    public function setEncoder(Swift_Mime_HeaderEncoder $encoder)
+    {
+        $this->encoder = $encoder;
+        $this->setCachedValue(null);
+    }
+
+    /**
+     * Get the encoder used for encoding this Header.
+     *
+     * @return Swift_Mime_HeaderEncoder
+     */
+    public function getEncoder()
+    {
+        return $this->encoder;
+    }
+
+    /**
+     * Get the name of this header (e.g. charset).
+     *
+     * @return string
+     */
+    public function getFieldName()
+    {
+        return $this->name;
+    }
+
+    /**
+     * Set the maximum length of lines in the header (excluding EOL).
+     *
+     * @param int $lineLength
+     */
+    public function setMaxLineLength($lineLength)
+    {
+        $this->clearCachedValueIf($this->lineLength != $lineLength);
+        $this->lineLength = $lineLength;
+    }
+
+    /**
+     * Get the maximum permitted length of lines in this Header.
+     *
+     * @return int
+     */
+    public function getMaxLineLength()
+    {
+        return $this->lineLength;
+    }
+
+    /**
+     * Get this Header rendered as a RFC 2822 compliant string.
+     *
+     * @return string
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function toString()
+    {
+        return $this->tokensToString($this->toTokens());
+    }
+
+    /**
+     * Returns a string representation of this object.
+     *
+     * @return string
+     *
+     * @see toString()
+     */
+    public function __toString()
+    {
+        return $this->toString();
+    }
+
+    /**
+     * Set the name of this Header field.
+     *
+     * @param string $name
+     */
+    protected function setFieldName($name)
+    {
+        $this->name = $name;
+    }
+
+    /**
+     * Produces a compliant, formatted RFC 2822 'phrase' based on the string given.
+     *
+     * @param string $string  as displayed
+     * @param string $charset of the text
+     * @param bool   $shorten the first line to make remove for header name
+     *
+     * @return string
+     */
+    protected function createPhrase(Swift_Mime_Header $header, $string, $charset, Swift_Mime_HeaderEncoder $encoder = null, $shorten = false)
+    {
+        // Treat token as exactly what was given
+        $phraseStr = $string;
+        // If it's not valid
+
+        if (!preg_match('/^'.self::PHRASE_PATTERN.'$/D', $phraseStr)) {
+            // .. but it is just ascii text, try escaping some characters
+            // and make it a quoted-string
+            if (preg_match('/^[\x00-\x08\x0B\x0C\x0E-\x7F]*$/D', $phraseStr)) {
+                $phraseStr = $this->escapeSpecials($phraseStr, ['"']);
+                $phraseStr = '"'.$phraseStr.'"';
+            } else {
+                // ... otherwise it needs encoding
+                // Determine space remaining on line if first line
+                if ($shorten) {
+                    $usedLength = \strlen($header->getFieldName().': ');
+                } else {
+                    $usedLength = 0;
+                }
+                $phraseStr = $this->encodeWords($header, $string, $usedLength);
+            }
+        }
+
+        return $phraseStr;
+    }
+
+    /**
+     * Escape special characters in a string (convert to quoted-pairs).
+     *
+     * @param string   $token
+     * @param string[] $include additional chars to escape
+     *
+     * @return string
+     */
+    private function escapeSpecials($token, $include = [])
+    {
+        foreach (array_merge(['\\'], $include) as $char) {
+            $token = str_replace($char, '\\'.$char, $token);
+        }
+
+        return $token;
+    }
+
+    /**
+     * Encode needed word tokens within a string of input.
+     *
+     * @param string $input
+     * @param string $usedLength optional
+     *
+     * @return string
+     */
+    protected function encodeWords(Swift_Mime_Header $header, $input, $usedLength = -1)
+    {
+        $value = '';
+
+        $tokens = $this->getEncodableWordTokens($input);
+
+        foreach ($tokens as $token) {
+            // See RFC 2822, Sect 2.2 (really 2.2 ??)
+            if ($this->tokenNeedsEncoding($token)) {
+                // Don't encode starting WSP
+                $firstChar = substr($token, 0, 1);
+                switch ($firstChar) {
+                    case ' ':
+                    case "\t":
+                        $value .= $firstChar;
+                        $token = substr($token, 1);
+                }
+
+                if (-1 == $usedLength) {
+                    $usedLength = \strlen($header->getFieldName().': ') + \strlen($value);
+                }
+                $value .= $this->getTokenAsEncodedWord($token, $usedLength);
+
+                $header->setMaxLineLength(76); // Forcefully override
+            } else {
+                $value .= $token;
+            }
+        }
+
+        return $value;
+    }
+
+    /**
+     * Test if a token needs to be encoded or not.
+     *
+     * @param string $token
+     *
+     * @return bool
+     */
+    protected function tokenNeedsEncoding($token)
+    {
+        return preg_match('~[\x00-\x08\x10-\x19\x7F-\xFF\r\n]~', $token);
+    }
+
+    /**
+     * Splits a string into tokens in blocks of words which can be encoded quickly.
+     *
+     * @param string $string
+     *
+     * @return string[]
+     */
+    protected function getEncodableWordTokens($string)
+    {
+        $tokens = [];
+
+        $encodedToken = '';
+        // Split at all whitespace boundaries
+        foreach (preg_split('~(?=[\t ])~', $string) as $token) {
+            if ($this->tokenNeedsEncoding($token)) {
+                $encodedToken .= $token;
+            } else {
+                if (\strlen($encodedToken) > 0) {
+                    $tokens[] = $encodedToken;
+                    $encodedToken = '';
+                }
+                $tokens[] = $token;
+            }
+        }
+        if (\strlen($encodedToken)) {
+            $tokens[] = $encodedToken;
+        }
+
+        return $tokens;
+    }
+
+    /**
+     * Get a token as an encoded word for safe insertion into headers.
+     *
+     * @param string $token           token to encode
+     * @param int    $firstLineOffset optional
+     *
+     * @return string
+     */
+    protected function getTokenAsEncodedWord($token, $firstLineOffset = 0)
+    {
+        // Adjust $firstLineOffset to account for space needed for syntax
+        $charsetDecl = $this->charset;
+        if (isset($this->lang)) {
+            $charsetDecl .= '*'.$this->lang;
+        }
+        $encodingWrapperLength = \strlen(
+            '=?'.$charsetDecl.'?'.$this->encoder->getName().'??='
+            );
+
+        if ($firstLineOffset >= 75) {
+            //Does this logic need to be here?
+            $firstLineOffset = 0;
+        }
+
+        $encodedTextLines = explode("\r\n",
+            $this->encoder->encodeString(
+                $token, $firstLineOffset, 75 - $encodingWrapperLength, $this->charset
+                )
+        );
+
+        if ('iso-2022-jp' !== strtolower($this->charset)) {
+            // special encoding for iso-2022-jp using mb_encode_mimeheader
+            foreach ($encodedTextLines as $lineNum => $line) {
+                $encodedTextLines[$lineNum] = '=?'.$charsetDecl.
+                    '?'.$this->encoder->getName().
+                    '?'.$line.'?=';
+            }
+        }
+
+        return implode("\r\n ", $encodedTextLines);
+    }
+
+    /**
+     * Generates tokens from the given string which include CRLF as individual tokens.
+     *
+     * @param string $token
+     *
+     * @return string[]
+     */
+    protected function generateTokenLines($token)
+    {
+        return preg_split('~(\r\n)~', $token, -1, PREG_SPLIT_DELIM_CAPTURE);
+    }
+
+    /**
+     * Set a value into the cache.
+     *
+     * @param string $value
+     */
+    protected function setCachedValue($value)
+    {
+        $this->cachedValue = $value;
+    }
+
+    /**
+     * Get the value in the cache.
+     *
+     * @return string
+     */
+    protected function getCachedValue()
+    {
+        return $this->cachedValue;
+    }
+
+    /**
+     * Clear the cached value if $condition is met.
+     *
+     * @param bool $condition
+     */
+    protected function clearCachedValueIf($condition)
+    {
+        if ($condition) {
+            $this->setCachedValue(null);
+        }
+    }
+
+    /**
+     * Generate a list of all tokens in the final header.
+     *
+     * @param string $string The string to tokenize
+     *
+     * @return array An array of tokens as strings
+     */
+    protected function toTokens($string = null)
+    {
+        if (null === $string) {
+            $string = $this->getFieldBody();
+        }
+
+        $tokens = [];
+
+        // Generate atoms; split at all invisible boundaries followed by WSP
+        foreach (preg_split('~(?=[ \t])~', $string) as $token) {
+            $newTokens = $this->generateTokenLines($token);
+            foreach ($newTokens as $newToken) {
+                $tokens[] = $newToken;
+            }
+        }
+
+        return $tokens;
+    }
+
+    /**
+     * Takes an array of tokens which appear in the header and turns them into
+     * an RFC 2822 compliant string, adding FWSP where needed.
+     *
+     * @param string[] $tokens
+     *
+     * @return string
+     */
+    private function tokensToString(array $tokens)
+    {
+        $lineCount = 0;
+        $headerLines = [];
+        $headerLines[] = $this->name.': ';
+        $currentLine = &$headerLines[$lineCount++];
+
+        // Build all tokens back into compliant header
+        foreach ($tokens as $i => $token) {
+            // Line longer than specified maximum or token was just a new line
+            if (("\r\n" == $token) ||
+                ($i > 0 && \strlen($currentLine.$token) > $this->lineLength)
+                && 0 < \strlen($currentLine)) {
+                $headerLines[] = '';
+                $currentLine = &$headerLines[$lineCount++];
+            }
+
+            // Append token to the line
+            if ("\r\n" != $token) {
+                $currentLine .= $token;
+            }
+        }
+
+        // Implode with FWS (RFC 2822, 2.2.3)
+        return implode("\r\n", $headerLines)."\r\n";
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/DateHeader.php

@@ -0,0 +1,113 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * A Date MIME Header for Swift Mailer.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Headers_DateHeader extends Swift_Mime_Headers_AbstractHeader
+{
+    /**
+     * Date-time value of this Header.
+     *
+     * @var DateTimeImmutable
+     */
+    private $dateTime;
+
+    /**
+     * Creates a new DateHeader with $name.
+     *
+     * @param string $name of Header
+     */
+    public function __construct($name)
+    {
+        $this->setFieldName($name);
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_DATE;
+    }
+
+    /**
+     * Set the model for the field body.
+     *
+     * @param DateTimeInterface $model
+     */
+    public function setFieldBodyModel($model)
+    {
+        $this->setDateTime($model);
+    }
+
+    /**
+     * Get the model for the field body.
+     *
+     * @return DateTimeImmutable
+     */
+    public function getFieldBodyModel()
+    {
+        return $this->getDateTime();
+    }
+
+    /**
+     * Get the date-time representing the Date in this Header.
+     *
+     * @return DateTimeImmutable
+     */
+    public function getDateTime()
+    {
+        return $this->dateTime;
+    }
+
+    /**
+     * Set the date-time of the Date in this Header.
+     *
+     * If a DateTime instance is provided, it is converted to DateTimeImmutable.
+     */
+    public function setDateTime(DateTimeInterface $dateTime)
+    {
+        $this->clearCachedValueIf($this->getCachedValue() != $dateTime->format(DateTime::RFC2822));
+        if ($dateTime instanceof DateTime) {
+            $immutable = new DateTimeImmutable('@'.$dateTime->getTimestamp());
+            $dateTime = $immutable->setTimezone($dateTime->getTimezone());
+        }
+        $this->dateTime = $dateTime;
+    }
+
+    /**
+     * Get the string value of the body in this Header.
+     *
+     * This is not necessarily RFC 2822 compliant since folding white space will
+     * not be added at this stage (see {@link toString()} for that).
+     *
+     * @see toString()
+     *
+     * @return string
+     */
+    public function getFieldBody()
+    {
+        if (!$this->getCachedValue()) {
+            if (isset($this->dateTime)) {
+                $this->setCachedValue($this->dateTime->format(DateTime::RFC2822));
+            }
+        }
+
+        return $this->getCachedValue();
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/IdentificationHeader.php

@@ -0,0 +1,189 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Egulias\EmailValidator\EmailValidator;
+use Egulias\EmailValidator\Validation\MessageIDValidation;
+use Egulias\EmailValidator\Validation\RFCValidation;
+
+/**
+ * An ID MIME Header for something like Message-ID or Content-ID.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Headers_IdentificationHeader extends Swift_Mime_Headers_AbstractHeader
+{
+    /**
+     * The IDs used in the value of this Header.
+     *
+     * This may hold multiple IDs or just a single ID.
+     *
+     * @var string[]
+     */
+    private $ids = [];
+
+    /**
+     * The strict EmailValidator.
+     *
+     * @var EmailValidator
+     */
+    private $emailValidator;
+
+    private $addressEncoder;
+
+    /**
+     * Creates a new IdentificationHeader with the given $name and $id.
+     *
+     * @param string $name
+     */
+    public function __construct($name, EmailValidator $emailValidator, Swift_AddressEncoder $addressEncoder = null)
+    {
+        $this->setFieldName($name);
+        $this->emailValidator = $emailValidator;
+        $this->addressEncoder = $addressEncoder ?? new Swift_AddressEncoder_IdnAddressEncoder();
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_ID;
+    }
+
+    /**
+     * Set the model for the field body.
+     *
+     * This method takes a string ID, or an array of IDs.
+     *
+     * @param mixed $model
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setFieldBodyModel($model)
+    {
+        $this->setId($model);
+    }
+
+    /**
+     * Get the model for the field body.
+     *
+     * This method returns an array of IDs
+     *
+     * @return array
+     */
+    public function getFieldBodyModel()
+    {
+        return $this->getIds();
+    }
+
+    /**
+     * Set the ID used in the value of this header.
+     *
+     * @param string|array $id
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setId($id)
+    {
+        $this->setIds(\is_array($id) ? $id : [$id]);
+    }
+
+    /**
+     * Get the ID used in the value of this Header.
+     *
+     * If multiple IDs are set only the first is returned.
+     *
+     * @return string
+     */
+    public function getId()
+    {
+        if (\count($this->ids) > 0) {
+            return $this->ids[0];
+        }
+    }
+
+    /**
+     * Set a collection of IDs to use in the value of this Header.
+     *
+     * @param string[] $ids
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setIds(array $ids)
+    {
+        $actualIds = [];
+
+        foreach ($ids as $id) {
+            $this->assertValidId($id);
+            $actualIds[] = $id;
+        }
+
+        $this->clearCachedValueIf($this->ids != $actualIds);
+        $this->ids = $actualIds;
+    }
+
+    /**
+     * Get the list of IDs used in this Header.
+     *
+     * @return string[]
+     */
+    public function getIds()
+    {
+        return $this->ids;
+    }
+
+    /**
+     * Get the string value of the body in this Header.
+     *
+     * This is not necessarily RFC 2822 compliant since folding white space will
+     * not be added at this stage (see {@see toString()} for that).
+     *
+     * @see toString()
+     *
+     * @throws Swift_RfcComplianceException
+     *
+     * @return string
+     */
+    public function getFieldBody()
+    {
+        if (!$this->getCachedValue()) {
+            $angleAddrs = [];
+
+            foreach ($this->ids as $id) {
+                $angleAddrs[] = '<'.$this->addressEncoder->encodeString($id).'>';
+            }
+
+            $this->setCachedValue(implode(' ', $angleAddrs));
+        }
+
+        return $this->getCachedValue();
+    }
+
+    /**
+     * Throws an Exception if the id passed does not comply with RFC 2822.
+     *
+     * @param string $id
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    private function assertValidId($id)
+    {
+        $emailValidation = class_exists(MessageIDValidation::class) ? new MessageIDValidation() : new RFCValidation();
+
+        if (!$this->emailValidator->isValid($id, $emailValidation)) {
+            throw new Swift_RfcComplianceException('Invalid ID given <'.$id.'>');
+        }
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/MailboxHeader.php

@@ -0,0 +1,358 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Egulias\EmailValidator\EmailValidator;
+use Egulias\EmailValidator\Validation\RFCValidation;
+
+/**
+ * A Mailbox Address MIME Header for something like From or Sender.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Headers_MailboxHeader extends Swift_Mime_Headers_AbstractHeader
+{
+    /**
+     * The mailboxes used in this Header.
+     *
+     * @var string[]
+     */
+    private $mailboxes = [];
+
+    /**
+     * The strict EmailValidator.
+     *
+     * @var EmailValidator
+     */
+    private $emailValidator;
+
+    private $addressEncoder;
+
+    /**
+     * Creates a new MailboxHeader with $name.
+     *
+     * @param string $name of Header
+     */
+    public function __construct($name, Swift_Mime_HeaderEncoder $encoder, EmailValidator $emailValidator, Swift_AddressEncoder $addressEncoder = null)
+    {
+        $this->setFieldName($name);
+        $this->setEncoder($encoder);
+        $this->emailValidator = $emailValidator;
+        $this->addressEncoder = $addressEncoder ?? new Swift_AddressEncoder_IdnAddressEncoder();
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_MAILBOX;
+    }
+
+    /**
+     * Set the model for the field body.
+     *
+     * This method takes a string, or an array of addresses.
+     *
+     * @param mixed $model
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setFieldBodyModel($model)
+    {
+        $this->setNameAddresses($model);
+    }
+
+    /**
+     * Get the model for the field body.
+     *
+     * This method returns an associative array like {@link getNameAddresses()}
+     *
+     * @throws Swift_RfcComplianceException
+     *
+     * @return array
+     */
+    public function getFieldBodyModel()
+    {
+        return $this->getNameAddresses();
+    }
+
+    /**
+     * Set a list of mailboxes to be shown in this Header.
+     *
+     * The mailboxes can be a simple array of addresses, or an array of
+     * key=>value pairs where (email => personalName).
+     * Example:
+     * <code>
+     * <?php
+     * //Sets two mailboxes in the Header, one with a personal name
+     * $header->setNameAddresses(array(
+     *  'chris@swiftmailer.org' => 'Chris Corbyn',
+     *  'mark@swiftmailer.org' //No associated personal name
+     *  ));
+     * ?>
+     * </code>
+     *
+     * @see __construct()
+     * @see setAddresses()
+     * @see setValue()
+     *
+     * @param string|string[] $mailboxes
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setNameAddresses($mailboxes)
+    {
+        $this->mailboxes = $this->normalizeMailboxes((array) $mailboxes);
+        $this->setCachedValue(null); //Clear any cached value
+    }
+
+    /**
+     * Get the full mailbox list of this Header as an array of valid RFC 2822 strings.
+     *
+     * Example:
+     * <code>
+     * <?php
+     * $header = new Swift_Mime_Headers_MailboxHeader('From',
+     *  array('chris@swiftmailer.org' => 'Chris Corbyn',
+     *  'mark@swiftmailer.org' => 'Mark Corbyn')
+     *  );
+     * print_r($header->getNameAddressStrings());
+     * // array (
+     * // 0 => Chris Corbyn <chris@swiftmailer.org>,
+     * // 1 => Mark Corbyn <mark@swiftmailer.org>
+     * // )
+     * ?>
+     * </code>
+     *
+     * @see getNameAddresses()
+     * @see toString()
+     *
+     * @throws Swift_RfcComplianceException
+     *
+     * @return string[]
+     */
+    public function getNameAddressStrings()
+    {
+        return $this->createNameAddressStrings($this->getNameAddresses());
+    }
+
+    /**
+     * Get all mailboxes in this Header as key=>value pairs.
+     *
+     * The key is the address and the value is the name (or null if none set).
+     * Example:
+     * <code>
+     * <?php
+     * $header = new Swift_Mime_Headers_MailboxHeader('From',
+     *  array('chris@swiftmailer.org' => 'Chris Corbyn',
+     *  'mark@swiftmailer.org' => 'Mark Corbyn')
+     *  );
+     * print_r($header->getNameAddresses());
+     * // array (
+     * // chris@swiftmailer.org => Chris Corbyn,
+     * // mark@swiftmailer.org => Mark Corbyn
+     * // )
+     * ?>
+     * </code>
+     *
+     * @see getAddresses()
+     * @see getNameAddressStrings()
+     *
+     * @return string[]
+     */
+    public function getNameAddresses()
+    {
+        return $this->mailboxes;
+    }
+
+    /**
+     * Makes this Header represent a list of plain email addresses with no names.
+     *
+     * Example:
+     * <code>
+     * <?php
+     * //Sets three email addresses as the Header data
+     * $header->setAddresses(
+     *  array('one@domain.tld', 'two@domain.tld', 'three@domain.tld')
+     *  );
+     * ?>
+     * </code>
+     *
+     * @see setNameAddresses()
+     * @see setValue()
+     *
+     * @param string[] $addresses
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setAddresses($addresses)
+    {
+        $this->setNameAddresses(array_values((array) $addresses));
+    }
+
+    /**
+     * Get all email addresses in this Header.
+     *
+     * @see getNameAddresses()
+     *
+     * @return string[]
+     */
+    public function getAddresses()
+    {
+        return array_keys($this->mailboxes);
+    }
+
+    /**
+     * Remove one or more addresses from this Header.
+     *
+     * @param string|string[] $addresses
+     */
+    public function removeAddresses($addresses)
+    {
+        $this->setCachedValue(null);
+        foreach ((array) $addresses as $address) {
+            unset($this->mailboxes[$address]);
+        }
+    }
+
+    /**
+     * Get the string value of the body in this Header.
+     *
+     * This is not necessarily RFC 2822 compliant since folding white space will
+     * not be added at this stage (see {@link toString()} for that).
+     *
+     * @see toString()
+     *
+     * @throws Swift_RfcComplianceException
+     *
+     * @return string
+     */
+    public function getFieldBody()
+    {
+        // Compute the string value of the header only if needed
+        if (null === $this->getCachedValue()) {
+            $this->setCachedValue($this->createMailboxListString($this->mailboxes));
+        }
+
+        return $this->getCachedValue();
+    }
+
+    /**
+     * Normalizes a user-input list of mailboxes into consistent key=>value pairs.
+     *
+     * @param string[] $mailboxes
+     *
+     * @return string[]
+     */
+    protected function normalizeMailboxes(array $mailboxes)
+    {
+        $actualMailboxes = [];
+
+        foreach ($mailboxes as $key => $value) {
+            if (\is_string($key)) {
+                //key is email addr
+                $address = $key;
+                $name = $value;
+            } else {
+                $address = $value;
+                $name = null;
+            }
+            $this->assertValidAddress($address);
+            $actualMailboxes[$address] = $name;
+        }
+
+        return $actualMailboxes;
+    }
+
+    /**
+     * Produces a compliant, formatted display-name based on the string given.
+     *
+     * @param string $displayName as displayed
+     * @param bool   $shorten     the first line to make remove for header name
+     *
+     * @return string
+     */
+    protected function createDisplayNameString($displayName, $shorten = false)
+    {
+        return $this->createPhrase($this, $displayName, $this->getCharset(), $this->getEncoder(), $shorten);
+    }
+
+    /**
+     * Creates a string form of all the mailboxes in the passed array.
+     *
+     * @param string[] $mailboxes
+     *
+     * @throws Swift_RfcComplianceException
+     *
+     * @return string
+     */
+    protected function createMailboxListString(array $mailboxes)
+    {
+        return implode(', ', $this->createNameAddressStrings($mailboxes));
+    }
+
+    /**
+     * Redefine the encoding requirements for mailboxes.
+     *
+     * All "specials" must be encoded as the full header value will not be quoted
+     *
+     * @see RFC 2822 3.2.1
+     *
+     * @param string $token
+     *
+     * @return bool
+     */
+    protected function tokenNeedsEncoding($token)
+    {
+        return preg_match('/[()<>\[\]:;@\,."]/', $token) || parent::tokenNeedsEncoding($token);
+    }
+
+    /**
+     * Return an array of strings conforming the the name-addr spec of RFC 2822.
+     *
+     * @param string[] $mailboxes
+     *
+     * @return string[]
+     */
+    private function createNameAddressStrings(array $mailboxes)
+    {
+        $strings = [];
+
+        foreach ($mailboxes as $email => $name) {
+            $mailboxStr = $this->addressEncoder->encodeString($email);
+            if (null !== $name) {
+                $nameStr = $this->createDisplayNameString($name, empty($strings));
+                $mailboxStr = $nameStr.' <'.$mailboxStr.'>';
+            }
+            $strings[] = $mailboxStr;
+        }
+
+        return $strings;
+    }
+
+    /**
+     * Throws an Exception if the address passed does not comply with RFC 2822.
+     *
+     * @param string $address
+     *
+     * @throws Swift_RfcComplianceException if invalid
+     */
+    private function assertValidAddress($address)
+    {
+        if (!$this->emailValidator->isValid($address, new RFCValidation())) {
+            throw new Swift_RfcComplianceException('Address in mailbox given ['.$address.'] does not comply with RFC 2822, 3.6.2.');
+        }
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/OpenDKIMHeader.php

@@ -0,0 +1,135 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * An OpenDKIM Specific Header using only raw header datas without encoding.
+ *
+ * @author De Cock Xavier <xdecock@gmail.com>
+ *
+ * @deprecated since SwiftMailer 6.1.0; use Swift_Signers_DKIMSigner instead.
+ */
+class Swift_Mime_Headers_OpenDKIMHeader implements Swift_Mime_Header
+{
+    /**
+     * The value of this Header.
+     *
+     * @var string
+     */
+    private $value;
+
+    /**
+     * The name of this Header.
+     *
+     * @var string
+     */
+    private $fieldName;
+
+    /**
+     * @param string $name
+     */
+    public function __construct($name)
+    {
+        $this->fieldName = $name;
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_TEXT;
+    }
+
+    /**
+     * Set the model for the field body.
+     *
+     * This method takes a string for the field value.
+     *
+     * @param string $model
+     */
+    public function setFieldBodyModel($model)
+    {
+        $this->setValue($model);
+    }
+
+    /**
+     * Get the model for the field body.
+     *
+     * This method returns a string.
+     *
+     * @return string
+     */
+    public function getFieldBodyModel()
+    {
+        return $this->getValue();
+    }
+
+    /**
+     * Get the (unencoded) value of this header.
+     *
+     * @return string
+     */
+    public function getValue()
+    {
+        return $this->value;
+    }
+
+    /**
+     * Set the (unencoded) value of this header.
+     *
+     * @param string $value
+     */
+    public function setValue($value)
+    {
+        $this->value = $value;
+    }
+
+    /**
+     * Get the value of this header prepared for rendering.
+     *
+     * @return string
+     */
+    public function getFieldBody()
+    {
+        return $this->value;
+    }
+
+    /**
+     * Get this Header rendered as a RFC 2822 compliant string.
+     *
+     * @return string
+     */
+    public function toString()
+    {
+        return $this->fieldName.': '.$this->value."\r\n";
+    }
+
+    /**
+     * Set the Header FieldName.
+     *
+     * @see Swift_Mime_Header::getFieldName()
+     */
+    public function getFieldName()
+    {
+        return $this->fieldName;
+    }
+
+    /**
+     * Ignored.
+     */
+    public function setCharset($charset)
+    {
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/ParameterizedHeader.php

@@ -0,0 +1,255 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * An abstract base MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Headers_ParameterizedHeader extends Swift_Mime_Headers_UnstructuredHeader
+{
+    /**
+     * RFC 2231's definition of a token.
+     *
+     * @var string
+     */
+    const TOKEN_REGEX = '(?:[\x21\x23-\x27\x2A\x2B\x2D\x2E\x30-\x39\x41-\x5A\x5E-\x7E]+)';
+
+    /**
+     * The Encoder used to encode the parameters.
+     *
+     * @var Swift_Encoder
+     */
+    private $paramEncoder;
+
+    /**
+     * The parameters as an associative array.
+     *
+     * @var string[]
+     */
+    private $params = [];
+
+    /**
+     * Creates a new ParameterizedHeader with $name.
+     *
+     * @param string $name
+     */
+    public function __construct($name, Swift_Mime_HeaderEncoder $encoder, Swift_Encoder $paramEncoder = null)
+    {
+        parent::__construct($name, $encoder);
+        $this->paramEncoder = $paramEncoder;
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_PARAMETERIZED;
+    }
+
+    /**
+     * Set the character set used in this Header.
+     *
+     * @param string $charset
+     */
+    public function setCharset($charset)
+    {
+        parent::setCharset($charset);
+        if (isset($this->paramEncoder)) {
+            $this->paramEncoder->charsetChanged($charset);
+        }
+    }
+
+    /**
+     * Set the value of $parameter.
+     *
+     * @param string $parameter
+     * @param string $value
+     */
+    public function setParameter($parameter, $value)
+    {
+        $this->setParameters(array_merge($this->getParameters(), [$parameter => $value]));
+    }
+
+    /**
+     * Get the value of $parameter.
+     *
+     * @param string $parameter
+     *
+     * @return string
+     */
+    public function getParameter($parameter)
+    {
+        $params = $this->getParameters();
+
+        return $params[$parameter] ?? null;
+    }
+
+    /**
+     * Set an associative array of parameter names mapped to values.
+     *
+     * @param string[] $parameters
+     */
+    public function setParameters(array $parameters)
+    {
+        $this->clearCachedValueIf($this->params != $parameters);
+        $this->params = $parameters;
+    }
+
+    /**
+     * Returns an associative array of parameter names mapped to values.
+     *
+     * @return string[]
+     */
+    public function getParameters()
+    {
+        return $this->params;
+    }
+
+    /**
+     * Get the value of this header prepared for rendering.
+     *
+     * @return string
+     */
+    public function getFieldBody() //TODO: Check caching here
+    {
+        $body = parent::getFieldBody();
+        foreach ($this->params as $name => $value) {
+            if (null !== $value) {
+                // Add the parameter
+                $body .= '; '.$this->createParameter($name, $value);
+            }
+        }
+
+        return $body;
+    }
+
+    /**
+     * Generate a list of all tokens in the final header.
+     *
+     * This doesn't need to be overridden in theory, but it is for implementation
+     * reasons to prevent potential breakage of attributes.
+     *
+     * @param string $string The string to tokenize
+     *
+     * @return array An array of tokens as strings
+     */
+    protected function toTokens($string = null)
+    {
+        $tokens = parent::toTokens(parent::getFieldBody());
+
+        // Try creating any parameters
+        foreach ($this->params as $name => $value) {
+            if (null !== $value) {
+                // Add the semi-colon separator
+                $tokens[\count($tokens) - 1] .= ';';
+                $tokens = array_merge($tokens, $this->generateTokenLines(
+                    ' '.$this->createParameter($name, $value)
+                    ));
+            }
+        }
+
+        return $tokens;
+    }
+
+    /**
+     * Render a RFC 2047 compliant header parameter from the $name and $value.
+     *
+     * @param string $name
+     * @param string $value
+     *
+     * @return string
+     */
+    private function createParameter($name, $value)
+    {
+        $origValue = $value;
+
+        $encoded = false;
+        // Allow room for parameter name, indices, "=" and DQUOTEs
+        $maxValueLength = $this->getMaxLineLength() - \strlen($name.'=*N"";') - 1;
+        $firstLineOffset = 0;
+
+        // If it's not already a valid parameter value...
+        if (!preg_match('/^'.self::TOKEN_REGEX.'$/D', $value)) {
+            // TODO: text, or something else??
+            // ... and it's not ascii
+            if (!preg_match('/^[\x00-\x08\x0B\x0C\x0E-\x7F]*$/D', $value)) {
+                $encoded = true;
+                // Allow space for the indices, charset and language
+                $maxValueLength = $this->getMaxLineLength() - \strlen($name.'*N*="";') - 1;
+                $firstLineOffset = \strlen(
+                    $this->getCharset()."'".$this->getLanguage()."'"
+                    );
+            }
+        }
+
+        // Encode if we need to
+        if ($encoded || \strlen($value) > $maxValueLength) {
+            if (isset($this->paramEncoder)) {
+                $value = $this->paramEncoder->encodeString(
+                    $origValue, $firstLineOffset, $maxValueLength, $this->getCharset()
+                    );
+            } else {
+                // We have to go against RFC 2183/2231 in some areas for interoperability
+                $value = $this->getTokenAsEncodedWord($origValue);
+                $encoded = false;
+            }
+        }
+
+        $valueLines = isset($this->paramEncoder) ? explode("\r\n", $value) : [$value];
+
+        // Need to add indices
+        if (\count($valueLines) > 1) {
+            $paramLines = [];
+            foreach ($valueLines as $i => $line) {
+                $paramLines[] = $name.'*'.$i.
+                    $this->getEndOfParameterValue($line, true, 0 == $i);
+            }
+
+            return implode(";\r\n ", $paramLines);
+        } else {
+            return $name.$this->getEndOfParameterValue(
+                $valueLines[0], $encoded, true
+                );
+        }
+    }
+
+    /**
+     * Returns the parameter value from the "=" and beyond.
+     *
+     * @param string $value     to append
+     * @param bool   $encoded
+     * @param bool   $firstLine
+     *
+     * @return string
+     */
+    private function getEndOfParameterValue($value, $encoded = false, $firstLine = false)
+    {
+        if (!preg_match('/^'.self::TOKEN_REGEX.'$/D', $value)) {
+            $value = '"'.$value.'"';
+        }
+        $prepend = '=';
+        if ($encoded) {
+            $prepend = '*=';
+            if ($firstLine) {
+                $prepend = '*='.$this->getCharset()."'".$this->getLanguage().
+                    "'";
+            }
+        }
+
+        return $prepend.$value;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/PathHeader.php

@@ -0,0 +1,153 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Egulias\EmailValidator\EmailValidator;
+use Egulias\EmailValidator\Validation\RFCValidation;
+
+/**
+ * A Path Header in Swift Mailer, such a Return-Path.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Headers_PathHeader extends Swift_Mime_Headers_AbstractHeader
+{
+    /**
+     * The address in this Header (if specified).
+     *
+     * @var string
+     */
+    private $address;
+
+    /**
+     * The strict EmailValidator.
+     *
+     * @var EmailValidator
+     */
+    private $emailValidator;
+
+    private $addressEncoder;
+
+    /**
+     * Creates a new PathHeader with the given $name.
+     *
+     * @param string $name
+     */
+    public function __construct($name, EmailValidator $emailValidator, Swift_AddressEncoder $addressEncoder = null)
+    {
+        $this->setFieldName($name);
+        $this->emailValidator = $emailValidator;
+        $this->addressEncoder = $addressEncoder ?? new Swift_AddressEncoder_IdnAddressEncoder();
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_PATH;
+    }
+
+    /**
+     * Set the model for the field body.
+     * This method takes a string for an address.
+     *
+     * @param string $model
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setFieldBodyModel($model)
+    {
+        $this->setAddress($model);
+    }
+
+    /**
+     * Get the model for the field body.
+     * This method returns a string email address.
+     *
+     * @return mixed
+     */
+    public function getFieldBodyModel()
+    {
+        return $this->getAddress();
+    }
+
+    /**
+     * Set the Address which should appear in this Header.
+     *
+     * @param string $address
+     *
+     * @throws Swift_RfcComplianceException
+     */
+    public function setAddress($address)
+    {
+        if (null === $address) {
+            $this->address = null;
+        } elseif ('' == $address) {
+            $this->address = '';
+        } else {
+            $this->assertValidAddress($address);
+            $this->address = $address;
+        }
+        $this->setCachedValue(null);
+    }
+
+    /**
+     * Get the address which is used in this Header (if any).
+     *
+     * Null is returned if no address is set.
+     *
+     * @return string
+     */
+    public function getAddress()
+    {
+        return $this->address;
+    }
+
+    /**
+     * Get the string value of the body in this Header.
+     *
+     * This is not necessarily RFC 2822 compliant since folding white space will
+     * not be added at this stage (see {@link toString()} for that).
+     *
+     * @see toString()
+     *
+     * @return string
+     */
+    public function getFieldBody()
+    {
+        if (!$this->getCachedValue()) {
+            if (isset($this->address)) {
+                $address = $this->addressEncoder->encodeString($this->address);
+                $this->setCachedValue('<'.$address.'>');
+            }
+        }
+
+        return $this->getCachedValue();
+    }
+
+    /**
+     * Throws an Exception if the address passed does not comply with RFC 2822.
+     *
+     * @param string $address
+     *
+     * @throws Swift_RfcComplianceException If address is invalid
+     */
+    private function assertValidAddress($address)
+    {
+        if (!$this->emailValidator->isValid($address, new RFCValidation())) {
+            throw new Swift_RfcComplianceException('Address set in PathHeader does not comply with addr-spec of RFC 2822.');
+        }
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/Headers/UnstructuredHeader.php

@@ -0,0 +1,109 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * A Simple MIME Header.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_Headers_UnstructuredHeader extends Swift_Mime_Headers_AbstractHeader
+{
+    /**
+     * The value of this Header.
+     *
+     * @var string
+     */
+    private $value;
+
+    /**
+     * Creates a new SimpleHeader with $name.
+     *
+     * @param string $name
+     */
+    public function __construct($name, Swift_Mime_HeaderEncoder $encoder)
+    {
+        $this->setFieldName($name);
+        $this->setEncoder($encoder);
+    }
+
+    /**
+     * Get the type of Header that this instance represents.
+     *
+     * @see TYPE_TEXT, TYPE_PARAMETERIZED, TYPE_MAILBOX
+     * @see TYPE_DATE, TYPE_ID, TYPE_PATH
+     *
+     * @return int
+     */
+    public function getFieldType()
+    {
+        return self::TYPE_TEXT;
+    }
+
+    /**
+     * Set the model for the field body.
+     *
+     * This method takes a string for the field value.
+     *
+     * @param string $model
+     */
+    public function setFieldBodyModel($model)
+    {
+        $this->setValue($model);
+    }
+
+    /**
+     * Get the model for the field body.
+     *
+     * This method returns a string.
+     *
+     * @return string
+     */
+    public function getFieldBodyModel()
+    {
+        return $this->getValue();
+    }
+
+    /**
+     * Get the (unencoded) value of this header.
+     *
+     * @return string
+     */
+    public function getValue()
+    {
+        return $this->value;
+    }
+
+    /**
+     * Set the (unencoded) value of this header.
+     *
+     * @param string $value
+     */
+    public function setValue($value)
+    {
+        $this->clearCachedValueIf($this->value != $value);
+        $this->value = $value;
+    }
+
+    /**
+     * Get the value of this header prepared for rendering.
+     *
+     * @return string
+     */
+    public function getFieldBody()
+    {
+        if (!$this->getCachedValue()) {
+            $this->setCachedValue(
+                $this->encodeWords($this, $this->value)
+                );
+        }
+
+        return $this->getCachedValue();
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/IdGenerator.php

@@ -0,0 +1,54 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * Message ID generator.
+ */
+class Swift_Mime_IdGenerator implements Swift_IdGenerator
+{
+    private $idRight;
+
+    /**
+     * @param string $idRight
+     */
+    public function __construct($idRight)
+    {
+        $this->idRight = $idRight;
+    }
+
+    /**
+     * Returns the right-hand side of the "@" used in all generated IDs.
+     *
+     * @return string
+     */
+    public function getIdRight()
+    {
+        return $this->idRight;
+    }
+
+    /**
+     * Sets the right-hand side of the "@" to use in all generated IDs.
+     *
+     * @param string $idRight
+     */
+    public function setIdRight($idRight)
+    {
+        $this->idRight = $idRight;
+    }
+
+    /**
+     * @return string
+     */
+    public function generateId()
+    {
+        // 32 hex values for the left part
+        return bin2hex(random_bytes(16)).'@'.$this->idRight;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/MimePart.php

@@ -0,0 +1,199 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * A MIME part, in a multipart message.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_MimePart extends Swift_Mime_SimpleMimeEntity
+{
+    /** The format parameter last specified by the user */
+    protected $userFormat;
+
+    /** The charset last specified by the user */
+    protected $userCharset;
+
+    /** The delsp parameter last specified by the user */
+    protected $userDelSp;
+
+    /** The nesting level of this MimePart */
+    private $nestingLevel = self::LEVEL_ALTERNATIVE;
+
+    /**
+     * Create a new MimePart with $headers, $encoder and $cache.
+     *
+     * @param string $charset
+     */
+    public function __construct(Swift_Mime_SimpleHeaderSet $headers, Swift_Mime_ContentEncoder $encoder, Swift_KeyCache $cache, Swift_IdGenerator $idGenerator, $charset = null)
+    {
+        parent::__construct($headers, $encoder, $cache, $idGenerator);
+        $this->setContentType('text/plain');
+        if (null !== $charset) {
+            $this->setCharset($charset);
+        }
+    }
+
+    /**
+     * Set the body of this entity, either as a string, or as an instance of
+     * {@link Swift_OutputByteStream}.
+     *
+     * @param mixed  $body
+     * @param string $contentType optional
+     * @param string $charset     optional
+     *
+     * @return $this
+     */
+    public function setBody($body, $contentType = null, $charset = null)
+    {
+        if (isset($charset)) {
+            $this->setCharset($charset);
+        }
+        $body = $this->convertString($body);
+
+        parent::setBody($body, $contentType);
+
+        return $this;
+    }
+
+    /**
+     * Get the character set of this entity.
+     *
+     * @return string
+     */
+    public function getCharset()
+    {
+        return $this->getHeaderParameter('Content-Type', 'charset');
+    }
+
+    /**
+     * Set the character set of this entity.
+     *
+     * @param string $charset
+     *
+     * @return $this
+     */
+    public function setCharset($charset)
+    {
+        $this->setHeaderParameter('Content-Type', 'charset', $charset);
+        if ($charset !== $this->userCharset) {
+            $this->clearCache();
+        }
+        $this->userCharset = $charset;
+        parent::charsetChanged($charset);
+
+        return $this;
+    }
+
+    /**
+     * Get the format of this entity (i.e. flowed or fixed).
+     *
+     * @return string
+     */
+    public function getFormat()
+    {
+        return $this->getHeaderParameter('Content-Type', 'format');
+    }
+
+    /**
+     * Set the format of this entity (flowed or fixed).
+     *
+     * @param string $format
+     *
+     * @return $this
+     */
+    public function setFormat($format)
+    {
+        $this->setHeaderParameter('Content-Type', 'format', $format);
+        $this->userFormat = $format;
+
+        return $this;
+    }
+
+    /**
+     * Test if delsp is being used for this entity.
+     *
+     * @return bool
+     */
+    public function getDelSp()
+    {
+        return 'yes' === $this->getHeaderParameter('Content-Type', 'delsp');
+    }
+
+    /**
+     * Turn delsp on or off for this entity.
+     *
+     * @param bool $delsp
+     *
+     * @return $this
+     */
+    public function setDelSp($delsp = true)
+    {
+        $this->setHeaderParameter('Content-Type', 'delsp', $delsp ? 'yes' : null);
+        $this->userDelSp = $delsp;
+
+        return $this;
+    }
+
+    /**
+     * Get the nesting level of this entity.
+     *
+     * @see LEVEL_TOP, LEVEL_ALTERNATIVE, LEVEL_MIXED, LEVEL_RELATED
+     *
+     * @return int
+     */
+    public function getNestingLevel()
+    {
+        return $this->nestingLevel;
+    }
+
+    /**
+     * Receive notification that the charset has changed on this document, or a
+     * parent document.
+     *
+     * @param string $charset
+     */
+    public function charsetChanged($charset)
+    {
+        $this->setCharset($charset);
+    }
+
+    /** Fix the content-type and encoding of this entity */
+    protected function fixHeaders()
+    {
+        parent::fixHeaders();
+        if (\count($this->getChildren())) {
+            $this->setHeaderParameter('Content-Type', 'charset', null);
+            $this->setHeaderParameter('Content-Type', 'format', null);
+            $this->setHeaderParameter('Content-Type', 'delsp', null);
+        } else {
+            $this->setCharset($this->userCharset);
+            $this->setFormat($this->userFormat);
+            $this->setDelSp($this->userDelSp);
+        }
+    }
+
+    /** Set the nesting level of this entity */
+    protected function setNestingLevel($level)
+    {
+        $this->nestingLevel = $level;
+    }
+
+    /** Encode charset when charset is not utf-8 */
+    protected function convertString($string)
+    {
+        $charset = strtolower($this->getCharset());
+        if (!\in_array($charset, ['utf-8', 'iso-8859-1', 'iso-8859-15', ''])) {
+            return mb_convert_encoding($string, $charset, 'utf-8');
+        }
+
+        return $string;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/SimpleHeaderFactory.php

@@ -0,0 +1,194 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Egulias\EmailValidator\EmailValidator;
+
+/**
+ * Creates MIME headers.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_SimpleHeaderFactory implements Swift_Mime_CharsetObserver
+{
+    /** The HeaderEncoder used by these headers */
+    private $encoder;
+
+    /** The Encoder used by parameters */
+    private $paramEncoder;
+
+    /** Strict EmailValidator */
+    private $emailValidator;
+
+    /** The charset of created Headers */
+    private $charset;
+
+    /** Swift_AddressEncoder */
+    private $addressEncoder;
+
+    /**
+     * Creates a new SimpleHeaderFactory using $encoder and $paramEncoder.
+     *
+     * @param string|null $charset
+     */
+    public function __construct(Swift_Mime_HeaderEncoder $encoder, Swift_Encoder $paramEncoder, EmailValidator $emailValidator, $charset = null, Swift_AddressEncoder $addressEncoder = null)
+    {
+        $this->encoder = $encoder;
+        $this->paramEncoder = $paramEncoder;
+        $this->emailValidator = $emailValidator;
+        $this->charset = $charset;
+        $this->addressEncoder = $addressEncoder ?? new Swift_AddressEncoder_IdnAddressEncoder();
+    }
+
+    /**
+     * Create a new Mailbox Header with a list of $addresses.
+     *
+     * @param string            $name
+     * @param array|string|null $addresses
+     *
+     * @return Swift_Mime_Header
+     */
+    public function createMailboxHeader($name, $addresses = null)
+    {
+        $header = new Swift_Mime_Headers_MailboxHeader($name, $this->encoder, $this->emailValidator, $this->addressEncoder);
+        if (isset($addresses)) {
+            $header->setFieldBodyModel($addresses);
+        }
+        $this->setHeaderCharset($header);
+
+        return $header;
+    }
+
+    /**
+     * Create a new Date header using $dateTime.
+     *
+     * @param string $name
+     *
+     * @return Swift_Mime_Header
+     */
+    public function createDateHeader($name, DateTimeInterface $dateTime = null)
+    {
+        $header = new Swift_Mime_Headers_DateHeader($name);
+        if (isset($dateTime)) {
+            $header->setFieldBodyModel($dateTime);
+        }
+        $this->setHeaderCharset($header);
+
+        return $header;
+    }
+
+    /**
+     * Create a new basic text header with $name and $value.
+     *
+     * @param string $name
+     * @param string $value
+     *
+     * @return Swift_Mime_Header
+     */
+    public function createTextHeader($name, $value = null)
+    {
+        $header = new Swift_Mime_Headers_UnstructuredHeader($name, $this->encoder);
+        if (isset($value)) {
+            $header->setFieldBodyModel($value);
+        }
+        $this->setHeaderCharset($header);
+
+        return $header;
+    }
+
+    /**
+     * Create a new ParameterizedHeader with $name, $value and $params.
+     *
+     * @param string $name
+     * @param string $value
+     * @param array  $params
+     *
+     * @return Swift_Mime_Headers_ParameterizedHeader
+     */
+    public function createParameterizedHeader($name, $value = null, $params = [])
+    {
+        $header = new Swift_Mime_Headers_ParameterizedHeader($name, $this->encoder, ('content-disposition' == strtolower($name)) ? $this->paramEncoder : null);
+        if (isset($value)) {
+            $header->setFieldBodyModel($value);
+        }
+        foreach ($params as $k => $v) {
+            $header->setParameter($k, $v);
+        }
+        $this->setHeaderCharset($header);
+
+        return $header;
+    }
+
+    /**
+     * Create a new ID header for Message-ID or Content-ID.
+     *
+     * @param string       $name
+     * @param string|array $ids
+     *
+     * @return Swift_Mime_Header
+     */
+    public function createIdHeader($name, $ids = null)
+    {
+        $header = new Swift_Mime_Headers_IdentificationHeader($name, $this->emailValidator);
+        if (isset($ids)) {
+            $header->setFieldBodyModel($ids);
+        }
+        $this->setHeaderCharset($header);
+
+        return $header;
+    }
+
+    /**
+     * Create a new Path header with an address (path) in it.
+     *
+     * @param string $name
+     * @param string $path
+     *
+     * @return Swift_Mime_Header
+     */
+    public function createPathHeader($name, $path = null)
+    {
+        $header = new Swift_Mime_Headers_PathHeader($name, $this->emailValidator);
+        if (isset($path)) {
+            $header->setFieldBodyModel($path);
+        }
+        $this->setHeaderCharset($header);
+
+        return $header;
+    }
+
+    /**
+     * Notify this observer that the entity's charset has changed.
+     *
+     * @param string $charset
+     */
+    public function charsetChanged($charset)
+    {
+        $this->charset = $charset;
+        $this->encoder->charsetChanged($charset);
+        $this->paramEncoder->charsetChanged($charset);
+    }
+
+    /**
+     * Make a deep copy of object.
+     */
+    public function __clone()
+    {
+        $this->encoder = clone $this->encoder;
+        $this->paramEncoder = clone $this->paramEncoder;
+    }
+
+    /** Apply the charset to the Header */
+    private function setHeaderCharset(Swift_Mime_Header $header)
+    {
+        if (isset($this->charset)) {
+            $header->setCharset($this->charset);
+        }
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/SimpleHeaderSet.php

@@ -0,0 +1,399 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * A collection of MIME headers.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_SimpleHeaderSet implements Swift_Mime_CharsetObserver
+{
+    /** HeaderFactory */
+    private $factory;
+
+    /** Collection of set Headers */
+    private $headers = [];
+
+    /** Field ordering details */
+    private $order = [];
+
+    /** List of fields which are required to be displayed */
+    private $required = [];
+
+    /** The charset used by Headers */
+    private $charset;
+
+    /**
+     * Create a new SimpleHeaderSet with the given $factory.
+     *
+     * @param string $charset
+     */
+    public function __construct(Swift_Mime_SimpleHeaderFactory $factory, $charset = null)
+    {
+        $this->factory = $factory;
+        if (isset($charset)) {
+            $this->setCharset($charset);
+        }
+    }
+
+    public function newInstance()
+    {
+        return new self($this->factory);
+    }
+
+    /**
+     * Set the charset used by these headers.
+     *
+     * @param string $charset
+     */
+    public function setCharset($charset)
+    {
+        $this->charset = $charset;
+        $this->factory->charsetChanged($charset);
+        $this->notifyHeadersOfCharset($charset);
+    }
+
+    /**
+     * Add a new Mailbox Header with a list of $addresses.
+     *
+     * @param string       $name
+     * @param array|string $addresses
+     */
+    public function addMailboxHeader($name, $addresses = null)
+    {
+        $this->storeHeader($name, $this->factory->createMailboxHeader($name, $addresses));
+    }
+
+    /**
+     * Add a new Date header using $dateTime.
+     *
+     * @param string $name
+     */
+    public function addDateHeader($name, DateTimeInterface $dateTime = null)
+    {
+        $this->storeHeader($name, $this->factory->createDateHeader($name, $dateTime));
+    }
+
+    /**
+     * Add a new basic text header with $name and $value.
+     *
+     * @param string $name
+     * @param string $value
+     */
+    public function addTextHeader($name, $value = null)
+    {
+        $this->storeHeader($name, $this->factory->createTextHeader($name, $value));
+    }
+
+    /**
+     * Add a new ParameterizedHeader with $name, $value and $params.
+     *
+     * @param string $name
+     * @param string $value
+     * @param array  $params
+     */
+    public function addParameterizedHeader($name, $value = null, $params = [])
+    {
+        $this->storeHeader($name, $this->factory->createParameterizedHeader($name, $value, $params));
+    }
+
+    /**
+     * Add a new ID header for Message-ID or Content-ID.
+     *
+     * @param string       $name
+     * @param string|array $ids
+     */
+    public function addIdHeader($name, $ids = null)
+    {
+        $this->storeHeader($name, $this->factory->createIdHeader($name, $ids));
+    }
+
+    /**
+     * Add a new Path header with an address (path) in it.
+     *
+     * @param string $name
+     * @param string $path
+     */
+    public function addPathHeader($name, $path = null)
+    {
+        $this->storeHeader($name, $this->factory->createPathHeader($name, $path));
+    }
+
+    /**
+     * Returns true if at least one header with the given $name exists.
+     *
+     * If multiple headers match, the actual one may be specified by $index.
+     *
+     * @param string $name
+     * @param int    $index
+     *
+     * @return bool
+     */
+    public function has($name, $index = 0)
+    {
+        $lowerName = strtolower($name);
+
+        if (!\array_key_exists($lowerName, $this->headers)) {
+            return false;
+        }
+
+        if (\func_num_args() < 2) {
+            // index was not specified, so we only need to check that there is at least one header value set
+            return (bool) \count($this->headers[$lowerName]);
+        }
+
+        return \array_key_exists($index, $this->headers[$lowerName]);
+    }
+
+    /**
+     * Set a header in the HeaderSet.
+     *
+     * The header may be a previously fetched header via {@link get()} or it may
+     * be one that has been created separately.
+     *
+     * If $index is specified, the header will be inserted into the set at this
+     * offset.
+     *
+     * @param int $index
+     */
+    public function set(Swift_Mime_Header $header, $index = 0)
+    {
+        $this->storeHeader($header->getFieldName(), $header, $index);
+    }
+
+    /**
+     * Get the header with the given $name.
+     *
+     * If multiple headers match, the actual one may be specified by $index.
+     * Returns NULL if none present.
+     *
+     * @param string $name
+     * @param int    $index
+     *
+     * @return Swift_Mime_Header|null
+     */
+    public function get($name, $index = 0)
+    {
+        $name = strtolower($name);
+
+        if (\func_num_args() < 2) {
+            if ($this->has($name)) {
+                $values = array_values($this->headers[$name]);
+
+                return array_shift($values);
+            }
+        } else {
+            if ($this->has($name, $index)) {
+                return $this->headers[$name][$index];
+            }
+        }
+    }
+
+    /**
+     * Get all headers with the given $name.
+     *
+     * @param string $name
+     *
+     * @return array
+     */
+    public function getAll($name = null)
+    {
+        if (!isset($name)) {
+            $headers = [];
+            foreach ($this->headers as $collection) {
+                $headers = array_merge($headers, $collection);
+            }
+
+            return $headers;
+        }
+
+        $lowerName = strtolower($name);
+        if (!\array_key_exists($lowerName, $this->headers)) {
+            return [];
+        }
+
+        return $this->headers[$lowerName];
+    }
+
+    /**
+     * Return the name of all Headers.
+     *
+     * @return array
+     */
+    public function listAll()
+    {
+        $headers = $this->headers;
+        if ($this->canSort()) {
+            uksort($headers, [$this, 'sortHeaders']);
+        }
+
+        return array_keys($headers);
+    }
+
+    /**
+     * Remove the header with the given $name if it's set.
+     *
+     * If multiple headers match, the actual one may be specified by $index.
+     *
+     * @param string $name
+     * @param int    $index
+     */
+    public function remove($name, $index = 0)
+    {
+        $lowerName = strtolower($name);
+        unset($this->headers[$lowerName][$index]);
+    }
+
+    /**
+     * Remove all headers with the given $name.
+     *
+     * @param string $name
+     */
+    public function removeAll($name)
+    {
+        $lowerName = strtolower($name);
+        unset($this->headers[$lowerName]);
+    }
+
+    /**
+     * Define a list of Header names as an array in the correct order.
+     *
+     * These Headers will be output in the given order where present.
+     */
+    public function defineOrdering(array $sequence)
+    {
+        $this->order = array_flip(array_map('strtolower', $sequence));
+    }
+
+    /**
+     * Set a list of header names which must always be displayed when set.
+     *
+     * Usually headers without a field value won't be output unless set here.
+     */
+    public function setAlwaysDisplayed(array $names)
+    {
+        $this->required = array_flip(array_map('strtolower', $names));
+    }
+
+    /**
+     * Notify this observer that the entity's charset has changed.
+     *
+     * @param string $charset
+     */
+    public function charsetChanged($charset)
+    {
+        $this->setCharset($charset);
+    }
+
+    /**
+     * Returns a string with a representation of all headers.
+     *
+     * @return string
+     */
+    public function toString()
+    {
+        $string = '';
+        $headers = $this->headers;
+        if ($this->canSort()) {
+            uksort($headers, [$this, 'sortHeaders']);
+        }
+        foreach ($headers as $collection) {
+            foreach ($collection as $header) {
+                if ($this->isDisplayed($header) || '' != $header->getFieldBody()) {
+                    $string .= $header->toString();
+                }
+            }
+        }
+
+        return $string;
+    }
+
+    /**
+     * Returns a string representation of this object.
+     *
+     * @return string
+     *
+     * @see toString()
+     */
+    public function __toString()
+    {
+        return $this->toString();
+    }
+
+    /** Save a Header to the internal collection */
+    private function storeHeader($name, Swift_Mime_Header $header, $offset = null)
+    {
+        if (!isset($this->headers[strtolower($name)])) {
+            $this->headers[strtolower($name)] = [];
+        }
+        if (!isset($offset)) {
+            $this->headers[strtolower($name)][] = $header;
+        } else {
+            $this->headers[strtolower($name)][$offset] = $header;
+        }
+    }
+
+    /** Test if the headers can be sorted */
+    private function canSort()
+    {
+        return \count($this->order) > 0;
+    }
+
+    /** uksort() algorithm for Header ordering */
+    private function sortHeaders($a, $b)
+    {
+        $lowerA = strtolower($a);
+        $lowerB = strtolower($b);
+        $aPos = \array_key_exists($lowerA, $this->order) ? $this->order[$lowerA] : -1;
+        $bPos = \array_key_exists($lowerB, $this->order) ? $this->order[$lowerB] : -1;
+
+        if (-1 === $aPos && -1 === $bPos) {
+            // just be sure to be determinist here
+            return $a > $b ? -1 : 1;
+        }
+
+        if (-1 == $aPos) {
+            return 1;
+        } elseif (-1 == $bPos) {
+            return -1;
+        }
+
+        return $aPos < $bPos ? -1 : 1;
+    }
+
+    /** Test if the given Header is always displayed */
+    private function isDisplayed(Swift_Mime_Header $header)
+    {
+        return \array_key_exists(strtolower($header->getFieldName()), $this->required);
+    }
+
+    /** Notify all Headers of the new charset */
+    private function notifyHeadersOfCharset($charset)
+    {
+        foreach ($this->headers as $headerGroup) {
+            foreach ($headerGroup as $header) {
+                $header->setCharset($charset);
+            }
+        }
+    }
+
+    /**
+     * Make a deep copy of object.
+     */
+    public function __clone()
+    {
+        $this->factory = clone $this->factory;
+        foreach ($this->headers as $groupKey => $headerGroup) {
+            foreach ($headerGroup as $key => $header) {
+                $this->headers[$groupKey][$key] = clone $header;
+            }
+        }
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/SimpleMessage.php

@@ -0,0 +1,642 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * The default email message class.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_SimpleMessage extends Swift_Mime_MimePart
+{
+    const PRIORITY_HIGHEST = 1;
+    const PRIORITY_HIGH = 2;
+    const PRIORITY_NORMAL = 3;
+    const PRIORITY_LOW = 4;
+    const PRIORITY_LOWEST = 5;
+
+    /**
+     * Create a new SimpleMessage with $headers, $encoder and $cache.
+     *
+     * @param string $charset
+     */
+    public function __construct(Swift_Mime_SimpleHeaderSet $headers, Swift_Mime_ContentEncoder $encoder, Swift_KeyCache $cache, Swift_IdGenerator $idGenerator, $charset = null)
+    {
+        parent::__construct($headers, $encoder, $cache, $idGenerator, $charset);
+        $this->getHeaders()->defineOrdering([
+            'Return-Path',
+            'Received',
+            'DKIM-Signature',
+            'DomainKey-Signature',
+            'Sender',
+            'Message-ID',
+            'Date',
+            'Subject',
+            'From',
+            'Reply-To',
+            'To',
+            'Cc',
+            'Bcc',
+            'MIME-Version',
+            'Content-Type',
+            'Content-Transfer-Encoding',
+            ]);
+        $this->getHeaders()->setAlwaysDisplayed(['Date', 'Message-ID', 'From']);
+        $this->getHeaders()->addTextHeader('MIME-Version', '1.0');
+        $this->setDate(new DateTimeImmutable());
+        $this->setId($this->getId());
+        $this->getHeaders()->addMailboxHeader('From');
+    }
+
+    /**
+     * Always returns {@link LEVEL_TOP} for a message instance.
+     *
+     * @return int
+     */
+    public function getNestingLevel()
+    {
+        return self::LEVEL_TOP;
+    }
+
+    /**
+     * Set the subject of this message.
+     *
+     * @param string $subject
+     *
+     * @return $this
+     */
+    public function setSubject($subject)
+    {
+        if (!$this->setHeaderFieldModel('Subject', $subject)) {
+            $this->getHeaders()->addTextHeader('Subject', $subject);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the subject of this message.
+     *
+     * @return string
+     */
+    public function getSubject()
+    {
+        return $this->getHeaderFieldModel('Subject');
+    }
+
+    /**
+     * Set the date at which this message was created.
+     *
+     * @return $this
+     */
+    public function setDate(DateTimeInterface $dateTime)
+    {
+        if (!$this->setHeaderFieldModel('Date', $dateTime)) {
+            $this->getHeaders()->addDateHeader('Date', $dateTime);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the date at which this message was created.
+     *
+     * @return DateTimeInterface
+     */
+    public function getDate()
+    {
+        return $this->getHeaderFieldModel('Date');
+    }
+
+    /**
+     * Set the return-path (the bounce address) of this message.
+     *
+     * @param string $address
+     *
+     * @return $this
+     */
+    public function setReturnPath($address)
+    {
+        if (!$this->setHeaderFieldModel('Return-Path', $address)) {
+            $this->getHeaders()->addPathHeader('Return-Path', $address);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the return-path (bounce address) of this message.
+     *
+     * @return string
+     */
+    public function getReturnPath()
+    {
+        return $this->getHeaderFieldModel('Return-Path');
+    }
+
+    /**
+     * Set the sender of this message.
+     *
+     * This does not override the From field, but it has a higher significance.
+     *
+     * @param string $address
+     * @param string $name    optional
+     *
+     * @return $this
+     */
+    public function setSender($address, $name = null)
+    {
+        if (!\is_array($address) && isset($name)) {
+            $address = [$address => $name];
+        }
+
+        if (!$this->setHeaderFieldModel('Sender', (array) $address)) {
+            $this->getHeaders()->addMailboxHeader('Sender', (array) $address);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the sender of this message.
+     *
+     * @return string
+     */
+    public function getSender()
+    {
+        return $this->getHeaderFieldModel('Sender');
+    }
+
+    /**
+     * Add a From: address to this message.
+     *
+     * If $name is passed this name will be associated with the address.
+     *
+     * @param string $address
+     * @param string $name    optional
+     *
+     * @return $this
+     */
+    public function addFrom($address, $name = null)
+    {
+        $current = $this->getFrom();
+        $current[$address] = $name;
+
+        return $this->setFrom($current);
+    }
+
+    /**
+     * Set the from address of this message.
+     *
+     * You may pass an array of addresses if this message is from multiple people.
+     *
+     * If $name is passed and the first parameter is a string, this name will be
+     * associated with the address.
+     *
+     * @param string|array $addresses
+     * @param string       $name      optional
+     *
+     * @return $this
+     */
+    public function setFrom($addresses, $name = null)
+    {
+        if (!\is_array($addresses) && isset($name)) {
+            $addresses = [$addresses => $name];
+        }
+
+        if (!$this->setHeaderFieldModel('From', (array) $addresses)) {
+            $this->getHeaders()->addMailboxHeader('From', (array) $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the from address of this message.
+     *
+     * @return mixed
+     */
+    public function getFrom()
+    {
+        return $this->getHeaderFieldModel('From');
+    }
+
+    /**
+     * Add a Reply-To: address to this message.
+     *
+     * If $name is passed this name will be associated with the address.
+     *
+     * @param string $address
+     * @param string $name    optional
+     *
+     * @return $this
+     */
+    public function addReplyTo($address, $name = null)
+    {
+        $current = $this->getReplyTo();
+        $current[$address] = $name;
+
+        return $this->setReplyTo($current);
+    }
+
+    /**
+     * Set the reply-to address of this message.
+     *
+     * You may pass an array of addresses if replies will go to multiple people.
+     *
+     * If $name is passed and the first parameter is a string, this name will be
+     * associated with the address.
+     *
+     * @param mixed  $addresses
+     * @param string $name      optional
+     *
+     * @return $this
+     */
+    public function setReplyTo($addresses, $name = null)
+    {
+        if (!\is_array($addresses) && isset($name)) {
+            $addresses = [$addresses => $name];
+        }
+
+        if (!$this->setHeaderFieldModel('Reply-To', (array) $addresses)) {
+            $this->getHeaders()->addMailboxHeader('Reply-To', (array) $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the reply-to address of this message.
+     *
+     * @return string
+     */
+    public function getReplyTo()
+    {
+        return $this->getHeaderFieldModel('Reply-To');
+    }
+
+    /**
+     * Add a To: address to this message.
+     *
+     * If $name is passed this name will be associated with the address.
+     *
+     * @param string $address
+     * @param string $name    optional
+     *
+     * @return $this
+     */
+    public function addTo($address, $name = null)
+    {
+        $current = $this->getTo();
+        $current[$address] = $name;
+
+        return $this->setTo($current);
+    }
+
+    /**
+     * Set the to addresses of this message.
+     *
+     * If multiple recipients will receive the message an array should be used.
+     * Example: array('receiver@domain.org', 'other@domain.org' => 'A name')
+     *
+     * If $name is passed and the first parameter is a string, this name will be
+     * associated with the address.
+     *
+     * @param mixed  $addresses
+     * @param string $name      optional
+     *
+     * @return $this
+     */
+    public function setTo($addresses, $name = null)
+    {
+        if (!\is_array($addresses) && isset($name)) {
+            $addresses = [$addresses => $name];
+        }
+
+        if (!$this->setHeaderFieldModel('To', (array) $addresses)) {
+            $this->getHeaders()->addMailboxHeader('To', (array) $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the To addresses of this message.
+     *
+     * @return array
+     */
+    public function getTo()
+    {
+        return $this->getHeaderFieldModel('To');
+    }
+
+    /**
+     * Add a Cc: address to this message.
+     *
+     * If $name is passed this name will be associated with the address.
+     *
+     * @param string $address
+     * @param string $name    optional
+     *
+     * @return $this
+     */
+    public function addCc($address, $name = null)
+    {
+        $current = $this->getCc();
+        $current[$address] = $name;
+
+        return $this->setCc($current);
+    }
+
+    /**
+     * Set the Cc addresses of this message.
+     *
+     * If $name is passed and the first parameter is a string, this name will be
+     * associated with the address.
+     *
+     * @param mixed  $addresses
+     * @param string $name      optional
+     *
+     * @return $this
+     */
+    public function setCc($addresses, $name = null)
+    {
+        if (!\is_array($addresses) && isset($name)) {
+            $addresses = [$addresses => $name];
+        }
+
+        if (!$this->setHeaderFieldModel('Cc', (array) $addresses)) {
+            $this->getHeaders()->addMailboxHeader('Cc', (array) $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the Cc address of this message.
+     *
+     * @return array
+     */
+    public function getCc()
+    {
+        return $this->getHeaderFieldModel('Cc');
+    }
+
+    /**
+     * Add a Bcc: address to this message.
+     *
+     * If $name is passed this name will be associated with the address.
+     *
+     * @param string $address
+     * @param string $name    optional
+     *
+     * @return $this
+     */
+    public function addBcc($address, $name = null)
+    {
+        $current = $this->getBcc();
+        $current[$address] = $name;
+
+        return $this->setBcc($current);
+    }
+
+    /**
+     * Set the Bcc addresses of this message.
+     *
+     * If $name is passed and the first parameter is a string, this name will be
+     * associated with the address.
+     *
+     * @param mixed  $addresses
+     * @param string $name      optional
+     *
+     * @return $this
+     */
+    public function setBcc($addresses, $name = null)
+    {
+        if (!\is_array($addresses) && isset($name)) {
+            $addresses = [$addresses => $name];
+        }
+
+        if (!$this->setHeaderFieldModel('Bcc', (array) $addresses)) {
+            $this->getHeaders()->addMailboxHeader('Bcc', (array) $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the Bcc addresses of this message.
+     *
+     * @return array
+     */
+    public function getBcc()
+    {
+        return $this->getHeaderFieldModel('Bcc');
+    }
+
+    /**
+     * Set the priority of this message.
+     *
+     * The value is an integer where 1 is the highest priority and 5 is the lowest.
+     *
+     * @param int $priority
+     *
+     * @return $this
+     */
+    public function setPriority($priority)
+    {
+        $priorityMap = [
+            self::PRIORITY_HIGHEST => 'Highest',
+            self::PRIORITY_HIGH => 'High',
+            self::PRIORITY_NORMAL => 'Normal',
+            self::PRIORITY_LOW => 'Low',
+            self::PRIORITY_LOWEST => 'Lowest',
+            ];
+        $pMapKeys = array_keys($priorityMap);
+        if ($priority > max($pMapKeys)) {
+            $priority = max($pMapKeys);
+        } elseif ($priority < min($pMapKeys)) {
+            $priority = min($pMapKeys);
+        }
+        if (!$this->setHeaderFieldModel('X-Priority',
+            sprintf('%d (%s)', $priority, $priorityMap[$priority]))) {
+            $this->getHeaders()->addTextHeader('X-Priority',
+                sprintf('%d (%s)', $priority, $priorityMap[$priority]));
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the priority of this message.
+     *
+     * The returned value is an integer where 1 is the highest priority and 5
+     * is the lowest.
+     *
+     * @return int
+     */
+    public function getPriority()
+    {
+        list($priority) = sscanf($this->getHeaderFieldModel('X-Priority'),
+            '%[1-5]'
+            );
+
+        return $priority ?? 3;
+    }
+
+    /**
+     * Ask for a delivery receipt from the recipient to be sent to $addresses.
+     *
+     * @param array $addresses
+     *
+     * @return $this
+     */
+    public function setReadReceiptTo($addresses)
+    {
+        if (!$this->setHeaderFieldModel('Disposition-Notification-To', $addresses)) {
+            $this->getHeaders()
+                ->addMailboxHeader('Disposition-Notification-To', $addresses);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the addresses to which a read-receipt will be sent.
+     *
+     * @return string
+     */
+    public function getReadReceiptTo()
+    {
+        return $this->getHeaderFieldModel('Disposition-Notification-To');
+    }
+
+    /**
+     * Attach a {@link Swift_Mime_SimpleMimeEntity} such as an Attachment or MimePart.
+     *
+     * @return $this
+     */
+    public function attach(Swift_Mime_SimpleMimeEntity $entity)
+    {
+        $this->setChildren(array_merge($this->getChildren(), [$entity]));
+
+        return $this;
+    }
+
+    /**
+     * Remove an already attached entity.
+     *
+     * @return $this
+     */
+    public function detach(Swift_Mime_SimpleMimeEntity $entity)
+    {
+        $newChildren = [];
+        foreach ($this->getChildren() as $child) {
+            if ($entity !== $child) {
+                $newChildren[] = $child;
+            }
+        }
+        $this->setChildren($newChildren);
+
+        return $this;
+    }
+
+    /**
+     * Attach a {@link Swift_Mime_SimpleMimeEntity} and return it's CID source.
+     *
+     * This method should be used when embedding images or other data in a message.
+     *
+     * @return string
+     */
+    public function embed(Swift_Mime_SimpleMimeEntity $entity)
+    {
+        $this->attach($entity);
+
+        return 'cid:'.$entity->getId();
+    }
+
+    /**
+     * Get this message as a complete string.
+     *
+     * @return string
+     */
+    public function toString()
+    {
+        if (\count($children = $this->getChildren()) > 0 && '' != $this->getBody()) {
+            $this->setChildren(array_merge([$this->becomeMimePart()], $children));
+            $string = parent::toString();
+            $this->setChildren($children);
+        } else {
+            $string = parent::toString();
+        }
+
+        return $string;
+    }
+
+    /**
+     * Returns a string representation of this object.
+     *
+     * @see toString()
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->toString();
+    }
+
+    /**
+     * Write this message to a {@link Swift_InputByteStream}.
+     */
+    public function toByteStream(Swift_InputByteStream $is)
+    {
+        if (\count($children = $this->getChildren()) > 0 && '' != $this->getBody()) {
+            $this->setChildren(array_merge([$this->becomeMimePart()], $children));
+            parent::toByteStream($is);
+            $this->setChildren($children);
+        } else {
+            parent::toByteStream($is);
+        }
+    }
+
+    /** @see Swift_Mime_SimpleMimeEntity::getIdField() */
+    protected function getIdField()
+    {
+        return 'Message-ID';
+    }
+
+    /** Turn the body of this message into a child of itself if needed */
+    protected function becomeMimePart()
+    {
+        $part = new parent($this->getHeaders()->newInstance(), $this->getEncoder(),
+            $this->getCache(), $this->getIdGenerator(), $this->userCharset
+            );
+        $part->setContentType($this->userContentType);
+        $part->setBody($this->getBody());
+        $part->setFormat($this->userFormat);
+        $part->setDelSp($this->userDelSp);
+        $part->setNestingLevel($this->getTopNestingLevel());
+
+        return $part;
+    }
+
+    /** Get the highest nesting level nested inside this message */
+    private function getTopNestingLevel()
+    {
+        $highestLevel = $this->getNestingLevel();
+        foreach ($this->getChildren() as $child) {
+            $childLevel = $child->getNestingLevel();
+            if ($highestLevel < $childLevel) {
+                $highestLevel = $childLevel;
+            }
+        }
+
+        return $highestLevel;
+    }
+}

include/swiftmailer/lib/classes/Swift/Mime/SimpleMimeEntity.php

@@ -0,0 +1,826 @@
+<?php
+
+/*
+ * This file is part of SwiftMailer.
+ * (c) 2004-2009 Chris Corbyn
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/**
+ * A MIME entity, in a multipart message.
+ *
+ * @author Chris Corbyn
+ */
+class Swift_Mime_SimpleMimeEntity implements Swift_Mime_CharsetObserver, Swift_Mime_EncodingObserver
+{
+    /** Main message document; there can only be one of these */
+    const LEVEL_TOP = 16;
+
+    /** An entity which nests with the same precedence as an attachment */
+    const LEVEL_MIXED = 256;
+
+    /** An entity which nests with the same precedence as a mime part */
+    const LEVEL_ALTERNATIVE = 4096;
+
+    /** An entity which nests with the same precedence as embedded content */
+    const LEVEL_RELATED = 65536;
+
+    /** A collection of Headers for this mime entity */
+    private $headers;
+
+    /** The body as a string, or a stream */
+    private $body;
+
+    /** The encoder that encodes the body into a streamable format */
+    private $encoder;
+
+    /** Message ID generator */
+    private $idGenerator;
+
+    /** A mime boundary, if any is used */
+    private $boundary;
+
+    /** Mime types to be used based on the nesting level */
+    private $compositeRanges = [
+        'multipart/mixed' => [self::LEVEL_TOP, self::LEVEL_MIXED],
+        'multipart/alternative' => [self::LEVEL_MIXED, self::LEVEL_ALTERNATIVE],
+        'multipart/related' => [self::LEVEL_ALTERNATIVE, self::LEVEL_RELATED],
+    ];
+
+    /** A set of filter rules to define what level an entity should be nested at */
+    private $compoundLevelFilters = [];
+
+    /** The nesting level of this entity */
+    private $nestingLevel = self::LEVEL_ALTERNATIVE;
+
+    /** A KeyCache instance used during encoding and streaming */
+    private $cache;
+
+    /** Direct descendants of this entity */
+    private $immediateChildren = [];
+
+    /** All descendants of this entity */
+    private $children = [];
+
+    /** The maximum line length of the body of this entity */
+    private $maxLineLength = 78;
+
+    /** The order in which alternative mime types should appear */
+    private $alternativePartOrder = [
+        'text/plain' => 1,
+        'text/html' => 2,
+        'multipart/related' => 3,
+    ];
+
+    /** The CID of this entity */
+    private $id;
+
+    /** The key used for accessing the cache */
+    private $cacheKey;
+
+    protected $userContentType;
+
+    /**
+     * Create a new SimpleMimeEntity with $headers, $encoder and $cache.
+     */
+    public function __construct(Swift_Mime_SimpleHeaderSet $headers, Swift_Mime_ContentEncoder $encoder, Swift_KeyCache $cache, Swift_IdGenerator $idGenerator)
+    {
+        $this->cacheKey = bin2hex(random_bytes(16)); // set 32 hex values
+        $this->cache = $cache;
+        $this->headers = $headers;
+        $this->idGenerator = $idGenerator;
+        $this->setEncoder($encoder);
+        $this->headers->defineOrdering(['Content-Type', 'Content-Transfer-Encoding']);
+
+        // This array specifies that, when the entire MIME document contains
+        // $compoundLevel, then for each child within $level, if its Content-Type
+        // is $contentType then it should be treated as if it's level is
+        // $neededLevel instead.  I tried to write that unambiguously! :-\
+        // Data Structure:
+        // array (
+        //   $compoundLevel => array(
+        //     $level => array(
+        //       $contentType => $neededLevel
+        //     )
+        //   )
+        // )
+
+        $this->compoundLevelFilters = [
+            (self::LEVEL_ALTERNATIVE + self::LEVEL_RELATED) => [
+                self::LEVEL_ALTERNATIVE => [
+                    'text/plain' => self::LEVEL_ALTERNATIVE,
+                    'text/html' => self::LEVEL_RELATED,
+                    ],
+                ],
+            ];
+
+        $this->id = $this->idGenerator->generateId();
+    }
+
+    /**
+     * Generate a new Content-ID or Message-ID for this MIME entity.
+     *
+     * @return string
+     */
+    public function generateId()
+    {
+        $this->setId($this->idGenerator->generateId());
+
+        return $this->id;
+    }
+
+    /**
+     * Get the {@link Swift_Mime_SimpleHeaderSet} for this entity.
+     *
+     * @return Swift_Mime_SimpleHeaderSet
+     */
+    public function getHeaders()
+    {
+        return $this->headers;
+    }
+
+    /**
+     * Get the nesting level of this entity.
+     *
+     * @see LEVEL_TOP, LEVEL_MIXED, LEVEL_RELATED, LEVEL_ALTERNATIVE
+     *
+     * @return int
+     */
+    public function getNestingLevel()
+    {
+        return $this->nestingLevel;
+    }
+
+    /**
+     * Get the Content-type of this entity.
+     *
+     * @return string
+     */
+    public function getContentType()
+    {
+        return $this->getHeaderFieldModel('Content-Type');
+    }
+
+    /**
+     * Get the Body Content-type of this entity.
+     *
+     * @return string
+     */
+    public function getBodyContentType()
+    {
+        return $this->userContentType;
+    }
+
+    /**
+     * Set the Content-type of this entity.
+     *
+     * @param string $type
+     *
+     * @return $this
+     */
+    public function setContentType($type)
+    {
+        $this->setContentTypeInHeaders($type);
+        // Keep track of the value so that if the content-type changes automatically
+        // due to added child entities, it can be restored if they are later removed
+        $this->userContentType = $type;
+
+        return $this;
+    }
+
+    /**
+     * Get the CID of this entity.
+     *
+     * The CID will only be present in headers if a Content-ID header is present.
+     *
+     * @return string
+     */
+    public function getId()
+    {
+        $tmp = (array) $this->getHeaderFieldModel($this->getIdField());
+
+        return $this->headers->has($this->getIdField()) ? current($tmp) : $this->id;
+    }
+
+    /**
+     * Set the CID of this entity.
+     *
+     * @param string $id
+     *
+     * @return $this
+     */
+    public function setId($id)
+    {
+        if (!$this->setHeaderFieldModel($this->getIdField(), $id)) {
+            $this->headers->addIdHeader($this->getIdField(), $id);
+        }
+        $this->id = $id;
+
+        return $this;
+    }
+
+    /**
+     * Get the description of this entity.
+     *
+     * This value comes from the Content-Description header if set.
+     *
+     * @return string
+     */
+    public function getDescription()
+    {
+        return $this->getHeaderFieldModel('Content-Description');
+    }
+
+    /**
+     * Set the description of this entity.
+     *
+     * This method sets a value in the Content-ID header.
+     *
+     * @param string $description
+     *
+     * @return $this
+     */
+    public function setDescription($description)
+    {
+        if (!$this->setHeaderFieldModel('Content-Description', $description)) {
+            $this->headers->addTextHeader('Content-Description', $description);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the maximum line length of the body of this entity.
+     *
+     * @return int
+     */
+    public function getMaxLineLength()
+    {
+        return $this->maxLineLength;
+    }
+
+    /**
+     * Set the maximum line length of lines in this body.
+     *
+     * Though not enforced by the library, lines should not exceed 1000 chars.
+     *
+     * @param int $length
+     *
+     * @return $this
+     */
+    public function setMaxLineLength($length)
+    {
+        $this->maxLineLength = $length;
+
+        return $this;
+    }
+
+    /**
+     * Get all children added to this entity.
+     *
+     * @return Swift_Mime_SimpleMimeEntity[]
+     */
+    public function getChildren()
+    {
+        return $this->children;
+    }
+
+    /**
+     * Set all children of this entity.
+     *
+     * @param Swift_Mime_SimpleMimeEntity[] $children
+     * @param int                           $compoundLevel For internal use only
+     *
+     * @return $this
+     */
+    public function setChildren(array $children, $compoundLevel = null)
+    {
+        // TODO: Try to refactor this logic
+        $compoundLevel = $compoundLevel ?? $this->getCompoundLevel($children);
+        $immediateChildren = [];
+        $grandchildren = [];
+        $newContentType = $this->userContentType;
+
+        foreach ($children as $child) {
+            $level = $this->getNeededChildLevel($child, $compoundLevel);
+            if (empty($immediateChildren)) {
+                //first iteration
+                $immediateChildren = [$child];
+            } else {
+                $nextLevel = $this->getNeededChildLevel($immediateChildren[0], $compoundLevel);
+                if ($nextLevel == $level) {
+                    $immediateChildren[] = $child;
+                } elseif ($level < $nextLevel) {
+                    // Re-assign immediateChildren to grandchildren
+                    $grandchildren = array_merge($grandchildren, $immediateChildren);
+                    // Set new children
+                    $immediateChildren = [$child];
+                } else {
+                    $grandchildren[] = $child;
+                }
+            }
+        }
+
+        if ($immediateChildren) {
+            $lowestLevel = $this->getNeededChildLevel($immediateChildren[0], $compoundLevel);
+
+            // Determine which composite media type is needed to accommodate the
+            // immediate children
+            foreach ($this->compositeRanges as $mediaType => $range) {
+                if ($lowestLevel > $range[0] && $lowestLevel <= $range[1]) {
+                    $newContentType = $mediaType;
+
+                    break;
+                }
+            }
+
+            // Put any grandchildren in a subpart
+            if (!empty($grandchildren)) {
+                $subentity = $this->createChild();
+                $subentity->setNestingLevel($lowestLevel);
+                $subentity->setChildren($grandchildren, $compoundLevel);
+                array_unshift($immediateChildren, $subentity);
+            }
+        }
+
+        $this->immediateChildren = $immediateChildren;
+        $this->children = $children;
+        $this->setContentTypeInHeaders($newContentType);
+        $this->fixHeaders();
+        $this->sortChildren();
+
+        return $this;
+    }
+
+    /**
+     * Get the body of this entity as a string.
+     *
+     * @return string
+     */
+    public function getBody()
+    {
+        return $this->body instanceof Swift_OutputByteStream ? $this->readStream($this->body) : $this->body;
+    }
+
+    /**
+     * Set the body of this entity, either as a string, or as an instance of
+     * {@link Swift_OutputByteStream}.
+     *
+     * @param mixed  $body
+     * @param string $contentType optional
+     *
+     * @return $this
+     */
+    public function setBody($body, $contentType = null)
+    {
+        if ($body !== $this->body) {
+            $this->clearCache();
+        }
+
+        $this->body = $body;
+        if (null !== $contentType) {
+            $this->setContentType($contentType);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Get the encoder used for the body of this entity.
+     *
+     * @return Swift_Mime_ContentEncoder
+     */
+    public function getEncoder()
+    {
+        return $this->encoder;
+    }
+
+    /**
+     * Set the encoder used for the body of this entity.
+     *
+     * @return $this
+     */
+    public function setEncoder(Swift_Mime_ContentEncoder $encoder)
+    {
+        if ($encoder !== $this->encoder) {
+            $this->clearCache();
+        }
+
+        $this->encoder = $encoder;
+        $this->setEncoding($encoder->getName());
+        $this->notifyEncoderChanged($encoder);
+
+        return $this;
+    }
+
+    /**
+     * Get the boundary used to separate children in this entity.
+     *
+     * @return string
+     */
+    public function getBoundary()
+    {
+        if (!isset($this->boundary)) {
+            $this->boundary = '_=_swift_'.time().'_'.bin2hex(random_bytes(16)).'_=_';
+        }
+
+        return $this->boundary;
+    }
+
+    /**
+     * Set the boundary used to separate children in this entity.
+     *
+     * @param string $boundary
+     *
+     * @throws Swift_RfcComplianceException
+     *
+     * @return $this
+     */
+    public function setBoundary($boundary)
+    {
+        $this->assertValidBoundary($boundary);
+        $this->boundary = $boundary;
+
+        return $this;
+    }
+
+    /**
+     * Receive notification that the charset of this entity, or a parent entity
+     * has changed.
+     *
+     * @param string $charset
+     */
+    public function charsetChanged($charset)
+    {
+        $this->notifyCharsetChanged($charset);
+    }
+
+    /**
+     * Receive notification that the encoder of this entity or a parent entity
+     * has changed.
+     */
+    public function encoderChanged(Swift_Mime_ContentEncoder $encoder)
+    {
+        $this->notifyEncoderChanged($encoder);
+    }
+
+    /**
+     * Get this entire entity as a string.
+     *
+     * @return string
+     */
+    public function toString()
+    {
+        $string = $this->headers->toString();
+        $string .= $this->bodyToString();
+
+        return $string;
+    }
+
+    /**
+     * Get this entire entity as a string.
+     *
+     * @return string
+     */
+    protected function bodyToString()
+    {
+        $string = '';
+
+        if (isset($this->body) && empty($this->immediateChildren)) {
+            if ($this->cache->hasKey($this->cacheKey, 'body')) {
+                $body = $this->cache->getString($this->cacheKey, 'body');
+            } else {
+                $body = "\r\n".$this->encoder->encodeString($this->getBody(), 0, $this->getMaxLineLength());
+                $this->cache->setString($this->cacheKey, 'body', $body, Swift_KeyCache::MODE_WRITE);
+            }
+            $string .= $body;
+        }
+
+        if (!empty($this->immediateChildren)) {
+            foreach ($this->immediateChildren as $child) {
+                $string .= "\r\n\r\n--".$this->getBoundary()."\r\n";
+                $string .= $child->toString();
+            }
+            $string .= "\r\n\r\n--".$this->getBoundary()."--\r\n";
+        }
+
+        return $string;
+    }
+
+    /**
+     * Returns a string representation of this object.
+     *
+     * @see toString()
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->toString();
+    }
+
+    /**
+     * Write this entire entity to a {@see Swift_InputByteStream}.
+     */
+    public function toByteStream(Swift_InputByteStream $is)
+    {
+        $is->write($this->headers->toString());
+        $is->commit();
+
+        $this->bodyToByteStream($is);
+    }
+
+    /**
+     * Write this entire entity to a {@link Swift_InputByteStream}.
+     */
+    protected function bodyToByteStream(Swift_InputByteStream $is)
+    {
+        if (empty($this->immediateChildren)) {
+            if (isset($this->body)) {
+                if ($this->cache->hasKey($this->cacheKey, 'body')) {
+                    $this->cache->exportToByteStream($this->cacheKey, 'body', $is);
+                } else {
+                    $cacheIs = $this->cache->getInputByteStream($this->cacheKey, 'body');
+                    if ($cacheIs) {
+                        $is->bind($cacheIs);
+                    }
+
+                    $is->write("\r\n");
+
+                    if ($this->body instanceof Swift_OutputByteStream) {
+                        $this->body->setReadPointer(0);
+
+                        $this->encoder->encodeByteStream($this->body, $is, 0, $this->getMaxLineLength());
+                    } else {
+                        $is->write($this->encoder->encodeString($this->getBody(), 0, $this->getMaxLineLength()));
+                    }
+
+                    if ($cacheIs) {
+                        $is->unbind($cacheIs);
+                    }
+                }
+            }
+        }
+
+        if (!empty($this->immediateChildren)) {
+            foreach ($this->immediateChildren as $child) {
+                $is->write("\r\n\r\n--".$this->getBoundary()."\r\n");
+                $child->toByteStream($is);
+            }
+            $is->write("\r\n\r\n--".$this->getBoundary()."--\r\n");
+        }
+    }
+
+    /**
+     * Get the name of the header that provides the ID of this entity.
+     */
+    protected function getIdField()
+    {
+        return 'Content-ID';
+    }
+
+    /**
+     * Get the model data (usually an array or a string) for $field.
+     */
+    protected function getHeaderFieldModel($field)
+    {
+        if ($this->headers->has($field)) {
+            return $this->headers->get($field)->getFieldBodyModel();
+        }
+    }
+
+    /**
+     * Set the model data for $field.
+     */
+    protected function setHeaderFieldModel($field, $model)
+    {
+        if ($this->headers->has($field)) {
+            $this->headers->get($field)->setFieldBodyModel($model);
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Get the parameter value of $parameter on $field header.
+     */
+    protected function getHeaderParameter($field, $parameter)
+    {
+        if ($this->headers->has($field)) {
+            return $this->headers->get($field)->getParameter($parameter);
+        }
+    }
+
+    /**
+     * Set the parameter value of $parameter on $field header.
+     */
+    protected function setHeaderParameter($field, $parameter, $value)
+    {
+        if ($this->headers->has($field)) {
+            $this->headers->get($field)->setParameter($parameter, $value);
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * Re-evaluate what content type and encoding should be used on this entity.
+     */
+    protected function fixHeaders()
+    {
+        if (\count($this->immediateChildren)) {
+            $this->setHeaderParameter('Content-Type', 'boundary',
+                $this->getBoundary()
+                );
+            $this->headers->remove('Content-Transfer-Encoding');
+        } else {
+            $this->setHeaderParameter('Content-Type', 'boundary', null);
+            $this->setEncoding($this->encoder->getName());
+        }
+    }
+
+    /**
+     * Get the KeyCache used in this entity.
+     *
+     * @return Swift_KeyCache
+     */
+    protected function getCache()
+    {
+        return $this->cache;
+    }
+
+    /**
+     * Get the ID generator.
+     *
+     * @return Swift_IdGenerator
+     */
+    protected function getIdGenerator()
+    {
+        return $this->idGenerator;
+    }
+
+    /**
+     * Empty the KeyCache for this entity.
+     */
+    protected function clearCache()
+    {
+        $this->cache->clearKey($this->cacheKey, 'body');
+    }
+
+    private function readStream(Swift_OutputByteStream $os)
+    {
+        $string = '';
+        while (false !== $bytes = $os->read(8192)) {
+            $string .= $bytes;
+        }
+
+        $os->setReadPointer(0);
+
+        return $string;
+    }
+
+    private function setEncoding($encoding)
+    {
+        if (!$this->setHeaderFieldModel('Content-Transfer-Encoding', $encoding)) {
+            $this->headers->addTextHeader('Content-Transfer-Encoding', $encoding);
+        }
+    }
+
+    private function assertValidBoundary($boundary)
+    {
+        if (!preg_match('/^[a-z0-9\'\(\)\+_\-,\.\/:=\?\ ]{0,69}[a-z0-9\'\(\)\+_\-,\.\/:=\?]$/Di', $boundary)) {
+            throw new Swift_RfcComplianceException('Mime boundary set is not RFC 2046 compliant.');
+        }
+    }
+
+    private function setContentTypeInHeaders($type)
+    {
+        if (!$this->setHeaderFieldModel('Content-Type', $type)) {
+            $this->headers->addParameterizedHeader('Content-Type', $type);
+        }
+    }
+
+    private function setNestingLevel($level)
+    {
+        $this->nestingLevel = $level;
+    }
+
+    private function getCompoundLevel($children)
+    {
+        $level = 0;
+        foreach ($children as $child) {
+            $level |= $child->getNestingLevel();
+        }
+
+        return $level;
+    }
+
+    private function getNeededChildLevel($child, $compoundLevel)
+    {
+        $filter = [];
+        foreach ($this->compoundLevelFilters as $bitmask => $rules) {
+            if (($compoundLevel & $bitmask) === $bitmask) {
+                $filter = $rules + $filter;
+            }
+        }
+
+        $realLevel = $child->getNestingLevel();
+        $lowercaseType = strtolower($child->getContentType());
+
+        if (isset($filter[$realLevel]) && isset($filter[$realLevel][$lowercaseType])) {
+            return $filter[$realLevel][$lowercaseType];
+        }
+
+        return $realLevel;
+    }
+
+    private function createChild()
+    {
+        return new self($this->headers->newInstance(), $this->encoder, $this->cache, $this->idGenerator);
+    }
+
+    private function notifyEncoderChanged(Swift_Mime_ContentEncoder $encoder)
+    {
+        foreach ($this->immediateChildren as $child) {
+            $child->encoderChanged($encoder);
+        }
+    }
+
+    private function notifyCharsetChanged($charset)
+    {
+        $this->encoder->charsetChanged($charset);
+        $this->headers->charsetChanged($charset);
+        foreach ($this->immediateChildren as $child) {
+            $child->charsetChanged($charset);
+        }
+    }
+
+    private function sortChildren()
+    {
+        $shouldSort = false;
+        foreach ($this->immediateChildren as $child) {
+            // NOTE: This include alternative parts moved into a related part
+            if (self::LEVEL_ALTERNATIVE == $child->getNestingLevel()) {
+                $shouldSort = true;
+                break;
+            }
+        }
+
+        // Sort in order of preference, if there is one
+        if ($shouldSort) {
+            // Group the messages by order of preference
+            $sorted = [];
+            foreach ($this->immediateChildren as $child) {
+                $type = $child->getContentType();
+                $level = \array_key_exists($type, $this->alternativePartOrder) ? $this->alternativePartOrder[$type] : max($this->alternativePartOrder) + 1;
+
+                if (empty($sorted[$level])) {
+                    $sorted[$level] = [];
+                }
+
+                $sorted[$level][] = $child;
+            }
+
+            ksort($sorted);
+
+            $this->immediateChildren = array_reduce($sorted, 'array_merge', []);
+        }
+    }
+
+    /**
+     * Empties it's own contents from the cache.
+     */
+    public function __destruct()
+    {
+        if ($this->cache instanceof Swift_KeyCache) {
+            $this->cache->clearAll($this->cacheKey);
+        }
+    }
+
+    /**
+     * Make a deep copy of object.
+     */
+    public function __clone()
+    {
+        $this->headers = clone $this->headers;
+        $this->encoder = clone $this->encoder;
+        $this->cacheKey = bin2hex(random_bytes(16)); // set 32 hex values
+        $children = [];
+        foreach ($this->children as $pos => $child) {
+            $children[$pos] = clone $child;
+        }
+        $this->setChildren($children);
+    }
+
+    public function __wakeup()
+    {
+        $this->cacheKey = bin2hex(random_bytes(16)); // set 32 hex values
+        $this->cache = new Swift_KeyCache_ArrayKeyCache(new Swift_KeyCache_SimpleKeyCacheInputStream());
+    }
+}