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+<?php
+/*
+UPDATES
+
+ 2008-08-10 Fixed CSS comment stripping regex to add PCRE_DOTALL (changed from '/\/\*.*\*\//U' to '/\/\*.*\*\//sU')
+ 2008-08-18 Added lines instructing DOMDocument to attempt to normalize HTML before processing
+ 2008-10-20 Fixed bug with bad variable name... Thanks Thomas!
+ 2008-03-02 Added licensing terms under the MIT License
+ Only remove unprocessable HTML tags if they exist in the array
+ 2009-06-03 Normalize existing CSS (style) attributes in the HTML before we process the CSS.
+ Made it so that the display:none stripper doesn't require a trailing semi-colon.
+ 2009-08-13 Added support for subset class values (e.g. "p.class1.class2").
+ Added better protection for bad css attributes.
+ Fixed support for HTML entities.
+ 2009-08-17 Fixed CSS selector processing so that selectors are processed by precedence/specificity, and not just in order.
+ 2009-10-29 Fixed so that selectors appearing later in the CSS will have precedence over identical selectors appearing earlier.
+ 2009-11-04 Explicitly declared static functions static to get rid of E_STRICT notices.
+ 2010-05-18 Fixed bug where full url filenames with protocols wouldn't get split improperly when we explode on ':'... Thanks Mark!
+ Added two new attribute selectors
+ 2010-06-16 Added static caching for less processing overhead in situations where multiple emogrification takes place
+ 2010-07-26 Fixed bug where '0' values were getting discarded because of php's empty() function... Thanks Scott!
+ 2010-09-03 Added checks to invisible node removal to ensure that we don't try to remove non-existent child nodes of parents that have already been deleted
+ 2011-04-08 Fixed errors in CSS->XPath conversion for adjacent sibling selectors and id/class combinations... Thanks Bob V.!
+ 2011-06-08 Fixed an error where CSS @media types weren't being parsed correctly... Thanks Will W.!
+ 2011-08-03 Fixed an error where an empty selector at the beginning of the CSS would cause a parse error on the next selector... Thanks Alexei T.!
+ 2011-10-13 Fully fixed a bug introduced in 2011-06-08 where selectors at the beginning of the CSS would be parsed incorrectly... Thanks Thomas A.!
+ 2011-10-26 Added an option to allow you to output emogrified code without extended characters being turned into HTML entities.
+ Moved static references to class attributes so they can be manipulated.
+ Added the ability to clear out the (formerly) static cache when CSS is reloaded.
+ 2011-12-22 Fixed a bug that was overwriting existing inline styles from the original HTML... Thanks Sagi L.!
+ 2012-01-31 Fixed a bug that was introduced with the 2011-12-22 revision... Thanks Sagi L. and M. BÄ…kowski!
+ Added extraction of <style> blocks within the HTML due to popular demand.
+ Added several new pseudo-selectors (first-child, last-child, nth-child, and nth-of-type).
+ 2012-02-07 Fixed some recent code introductions to use class constants rather than global constants.
+ Fixed some recent code introductions to make it cleaner to read.
+ 2012-05-01 Made removal of invisible nodes operate in a case-insensitive manner... Thanks Juha P.!
+ 2013-10-10 Add preserveStyleTag option
+*/
+
+define('CACHE_CSS', 0);
+define('CACHE_SELECTOR', 1);
+define('CACHE_XPATH', 2);
+
+class Emogrifier {
+
+ // for calculating nth-of-type and nth-child selectors
+ const INDEX = 0;
+ const MULTIPLIER = 1;
+
+ private $html = '';
+ private $css = '';
+ private $unprocessableHTMLTags = array('wbr');
+ private $caches = array();
+
+ // this attribute applies to the case where you want to preserve your original text encoding.
+ // by default, emogrifier translates your text into HTML entities for two reasons:
+ // 1. because of client incompatibilities, it is better practice to send out HTML entities rather than unicode over email
+ // 2. it translates any illegal XML characters that DOMDocument cannot work with
+ // if you would like to preserve your original encoding, set this attribute to true.
+ public $preserveEncoding = false;
+
+ // by default, emogrifier removes <style> tags, set preserveStyleTag to true to keep them
+ public $preserveStyleTag = false;
+
+ public function __construct($html = '', $css = '') {
+ $this->html = $html;
+ $this->css = $css;
+ $this->clearCache();
+ }
+
+ public function setHTML($html = '') { $this->html = $html; }
+ public function setCSS($css = '') {
+ $this->css = $css;
+ $this->clearCache(CACHE_CSS);
+ }
+
+ public function clearCache($key = null) {
+ if (!is_null($key)) {
+ if (isset($this->caches[$key])) $this->caches[$key] = array();
+ } else {
+ $this->caches = array(
+ CACHE_CSS => array(),
+ CACHE_SELECTOR => array(),
+ CACHE_XPATH => array(),
+ );
+ }
+ }
+
+ // there are some HTML tags that DOMDocument cannot process, and will throw an error if it encounters them.
+ // in particular, DOMDocument will complain if you try to use HTML5 tags in an XHTML document.
+ // these functions allow you to add/remove them if necessary.
+ // it only strips them from the code (does not remove actual nodes).
+ public function addUnprocessableHTMLTag($tag) { $this->unprocessableHTMLTags[] = $tag; }
+ public function removeUnprocessableHTMLTag($tag) {
+ if (($key = array_search($tag,$this->unprocessableHTMLTags)) !== false)
+ unset($this->unprocessableHTMLTags[$key]);
+ }
+
+ // applies the CSS you submit to the html you submit. places the css inline
+ public function emogrify() {
+ $body = $this->html;
+
+ // remove any unprocessable HTML tags (tags that DOMDocument cannot parse; this includes wbr and many new HTML5 tags)
+ if (count($this->unprocessableHTMLTags)) {
+ $unprocessableHTMLTags = implode('|',$this->unprocessableHTMLTags);
+ $body = preg_replace("/<\/?($unprocessableHTMLTags)[^>]*>/i",'',$body);
+ }
+
+ $encoding = mb_detect_encoding($body);
+ $body = mb_convert_encoding($body, 'HTML-ENTITIES', $encoding);
+
+ $xmldoc = new DOMDocument;
+ $xmldoc->encoding = $encoding;
+ $xmldoc->strictErrorChecking = false;
+ $xmldoc->formatOutput = true;
+ $xmldoc->loadHTML($body);
+ $xmldoc->normalizeDocument();
+
+ $xpath = new DOMXPath($xmldoc);
+
+ // before be begin processing the CSS file, parse the document and normalize all existing CSS attributes (changes 'DISPLAY: none' to 'display: none');
+ // we wouldn't have to do this if DOMXPath supported XPath 2.0.
+ // also store a reference of nodes with existing inline styles so we don't overwrite them
+ $vistedNodes = $vistedNodeRef = array();
+ $nodes = @$xpath->query('//*[@style]');
+ foreach ($nodes as $node) {
+ $normalizedOrigStyle = preg_replace('/[A-z\-]+(?=\:)/Se',"strtolower('\\0')", $node->getAttribute('style'));
+
+ // in order to not overwrite existing style attributes in the HTML, we have to save the original HTML styles
+ $nodeKey = md5($node->getNodePath());
+ if (!isset($vistedNodeRef[$nodeKey])) {
+ $vistedNodeRef[$nodeKey] = $this->cssStyleDefinitionToArray($normalizedOrigStyle);
+ $vistedNodes[$nodeKey] = $node;
+ }
+
+ $node->setAttribute('style', $normalizedOrigStyle);
+ }
+
+ // grab any existing style blocks from the html and append them to the existing CSS
+ // (these blocks should be appended so as to have precedence over conflicting styles in the existing CSS)
+ $css = $this->css;
+ $nodes = @$xpath->query('//style');
+ foreach ($nodes as $node) {
+ // append the css
+ $css .= "\n\n{$node->nodeValue}";
+ // remove the <style> node
+ if (!$this->preserveStyleTag) {
+ $node->parentNode->removeChild($node);
+ }
+ }
+
+ // filter the CSS
+ $search = array(
+ '/\/\*.*\*\//sU', // get rid of css comment code
+ '/^\s*@import\s[^;]+;/misU', // strip out any import directives
+ '/^\s*@media\s[^{]+{\s*}/misU', // strip any empty media enclosures
+ '/^\s*@media\s+((aural|braille|embossed|handheld|print|projection|speech|tty|tv)\s*,*\s*)+{.*}\s*}/misU', // strip out all media types that are not 'screen' or 'all' (these don't apply to email)
+ '/^\s*@media\s[^{]+{(.*})\s*}/misU', // get rid of remaining media type enclosures
+ );
+
+ $replace = array(
+ '',
+ '',
+ '',
+ '',
+ '\\1',
+ );
+
+ $css = preg_replace($search, $replace, $css);
+
+ $csskey = md5($css);
+ if (!isset($this->caches[CACHE_CSS][$csskey])) {
+
+ // process the CSS file for selectors and definitions
+ preg_match_all('/(^|[^{}])\s*([^{]+){([^}]*)}/mis', $css, $matches, PREG_SET_ORDER);
+
+ $all_selectors = array();
+ foreach ($matches as $key => $selectorString) {
+ // if there is a blank definition, skip
+ if (!strlen(trim($selectorString[3]))) continue;
+
+ // else split by commas and duplicate attributes so we can sort by selector precedence
+ $selectors = explode(',',$selectorString[2]);
+ foreach ($selectors as $selector) {
+
+ // don't process pseudo-elements and behavioral (dynamic) pseudo-classes; ONLY allow structural pseudo-classes
+ if (strpos($selector, ':') !== false && !preg_match('/:\S+\-(child|type)\(/i', $selector)) continue;
+
+ $all_selectors[] = array('selector' => trim($selector),
+ 'attributes' => trim($selectorString[3]),
+ 'line' => $key, // keep track of where it appears in the file, since order is important
+ );
+ }
+ }
+
+ // now sort the selectors by precedence
+ usort($all_selectors, array($this,'sortBySelectorPrecedence'));
+
+ $this->caches[CACHE_CSS][$csskey] = $all_selectors;
+ }
+
+ foreach ($this->caches[CACHE_CSS][$csskey] as $value) {
+
+ // query the body for the xpath selector
+ $nodes = $xpath->query($this->translateCSStoXpath(trim($value['selector'])));
+
+ foreach($nodes as $node) {
+ // if it has a style attribute, get it, process it, and append (overwrite) new stuff
+ if ($node->hasAttribute('style')) {
+ // break it up into an associative array
+ $oldStyleArr = $this->cssStyleDefinitionToArray($node->getAttribute('style'));
+ $newStyleArr = $this->cssStyleDefinitionToArray($value['attributes']);
+
+ // new styles overwrite the old styles (not technically accurate, but close enough)
+ $combinedArr = array_merge($oldStyleArr,$newStyleArr);
+ $style = '';
+ foreach ($combinedArr as $k => $v) $style .= (strtolower($k) . ':' . $v . ';');
+ } else {
+ // otherwise create a new style
+ $style = trim($value['attributes']);
+ }
+ $node->setAttribute('style', $style);
+ }
+ }
+
+ // now iterate through the nodes that contained inline styles in the original HTML
+ foreach ($vistedNodeRef as $nodeKey => $origStyleArr) {
+ $node = $vistedNodes[$nodeKey];
+ $currStyleArr = $this->cssStyleDefinitionToArray($node->getAttribute('style'));
+
+ $combinedArr = array_merge($currStyleArr, $origStyleArr);
+ $style = '';
+ foreach ($combinedArr as $k => $v) $style .= (strtolower($k) . ':' . $v . ';');
+
+ $node->setAttribute('style', $style);
+ }
+
+ // This removes styles from your email that contain display:none.
+ // We need to look for display:none, but we need to do a case-insensitive search. Since DOMDocument only supports XPath 1.0,
+ // lower-case() isn't available to us. We've thus far only set attributes to lowercase, not attribute values. Consequently, we need
+ // to translate() the letters that would be in 'NONE' ("NOE") to lowercase.
+ $nodes = $xpath->query('//*[contains(translate(translate(@style," ",""),"NOE","noe"),"display:none")]');
+ // The checks on parentNode and is_callable below ensure that if we've deleted the parent node,
+ // we don't try to call removeChild on a nonexistent child node
+ if ($nodes->length > 0)
+ foreach ($nodes as $node)
+ if ($node->parentNode && is_callable(array($node->parentNode,'removeChild')))
+ $node->parentNode->removeChild($node);
+
+ if ($this->preserveEncoding) {
+ return mb_convert_encoding($xmldoc->saveHTML(), $encoding, 'HTML-ENTITIES');
+ } else {
+ return $xmldoc->saveHTML();
+ }
+ }
+
+ private function sortBySelectorPrecedence($a, $b) {
+ $precedenceA = $this->getCSSSelectorPrecedence($a['selector']);
+ $precedenceB = $this->getCSSSelectorPrecedence($b['selector']);
+
+ // we want these sorted ascendingly so selectors with lesser precedence get processed first and
+ // selectors with greater precedence get sorted last
+ return ($precedenceA == $precedenceB) ? ($a['line'] < $b['line'] ? -1 : 1) : ($precedenceA < $precedenceB ? -1 : 1);
+ }
+
+ private function getCSSSelectorPrecedence($selector) {
+ $selectorkey = md5($selector);
+ if (!isset($this->caches[CACHE_SELECTOR][$selectorkey])) {
+ $precedence = 0;
+ $value = 100;
+ $search = array('\#','\.',''); // ids: worth 100, classes: worth 10, elements: worth 1
+
+ foreach ($search as $s) {
+ if (trim($selector == '')) break;
+ $num = 0;
+ $selector = preg_replace('/'.$s.'\w+/','',$selector,-1,$num);
+ $precedence += ($value * $num);
+ $value /= 10;
+ }
+ $this->caches[CACHE_SELECTOR][$selectorkey] = $precedence;
+ }
+
+ return $this->caches[CACHE_SELECTOR][$selectorkey];
+ }
+
+ // right now we support all CSS 1 selectors and most CSS2/3 selectors.
+ // http://plasmasturm.org/log/444/
+ private function translateCSStoXpath($css_selector) {
+
+ $css_selector = trim($css_selector);
+ $xpathkey = md5($css_selector);
+ if (!isset($this->caches[CACHE_XPATH][$xpathkey])) {
+ // returns an Xpath selector
+ $search = array(
+ '/\s+>\s+/', // Matches any element that is a child of parent.
+ '/\s+\+\s+/', // Matches any element that is an adjacent sibling.
+ '/\s+/', // Matches any element that is a descendant of an parent element element.
+ '/([^\/]+):first-child/i', // first-child pseudo-selector
+ '/([^\/]+):last-child/i', // last-child pseudo-selector
+ '/(\w)\[(\w+)\]/', // Matches element with attribute
+ '/(\w)\[(\w+)\=[\'"]?(\w+)[\'"]?\]/', // Matches element with EXACT attribute
+ '/(\w+)?\#([\w\-]+)/e', // Matches id attributes
+ '/(\w+|[\*\]])?((\.[\w\-]+)+)/e', // Matches class attributes
+
+ );
+ $replace = array(
+ '/',
+ '/following-sibling::*[1]/self::',
+ '//',
+ '*[1]/self::\\1',
+ '*[last()]/self::\\1',
+ '\\1[@\\2]',
+ '\\1[@\\2="\\3"]',
+ "(strlen('\\1') ? '\\1' : '*').'[@id=\"\\2\"]'",
+ "(strlen('\\1') ? '\\1' : '*').'[contains(concat(\" \",@class,\" \"),concat(\" \",\"'.implode('\",\" \"))][contains(concat(\" \",@class,\" \"),concat(\" \",\"',explode('.',substr('\\2',1))).'\",\" \"))]'",
+ );
+
+ $css_selector = '//'.preg_replace($search, $replace, $css_selector);
+
+ // advanced selectors are going to require a bit more advanced emogrification
+ // if we required PHP 5.3 we could do this with closures
+ $css_selector = preg_replace_callback('/([^\/]+):nth-child\(\s*(odd|even|[+\-]?\d|[+\-]?\d?n(\s*[+\-]\s*\d)?)\s*\)/i', array($this, 'translateNthChild'), $css_selector);
+ $css_selector = preg_replace_callback('/([^\/]+):nth-of-type\(\s*(odd|even|[+\-]?\d|[+\-]?\d?n(\s*[+\-]\s*\d)?)\s*\)/i', array($this, 'translateNthOfType'), $css_selector);
+
+ $this->caches[CACHE_SELECTOR][$xpathkey] = $css_selector;
+ }
+ return $this->caches[CACHE_SELECTOR][$xpathkey];
+ }
+
+ private function translateNthChild($match) {
+
+ $result = $this->parseNth($match);
+
+ if (isset($result[self::MULTIPLIER])) {
+ if ($result[self::MULTIPLIER] < 0) {
+ $result[self::MULTIPLIER] = abs($result[self::MULTIPLIER]);
+ return sprintf("*[(last() - position()) mod %u = %u]/self::%s", $result[self::MULTIPLIER], $result[self::INDEX], $match[1]);
+ } else {
+ return sprintf("*[position() mod %u = %u]/self::%s", $result[self::MULTIPLIER], $result[self::INDEX], $match[1]);
+ }
+ } else {
+ return sprintf("*[%u]/self::%s", $result[self::INDEX], $match[1]);
+ }
+ }
+
+ private function translateNthOfType($match) {
+
+ $result = $this->parseNth($match);
+
+ if (isset($result[self::MULTIPLIER])) {
+ if ($result[self::MULTIPLIER] < 0) {
+ $result[self::MULTIPLIER] = abs($result[self::MULTIPLIER]);
+ return sprintf("%s[(last() - position()) mod %u = %u]", $match[1], $result[self::MULTIPLIER], $result[self::INDEX]);
+ } else {
+ return sprintf("%s[position() mod %u = %u]", $match[1], $result[self::MULTIPLIER], $result[self::INDEX]);
+ }
+ } else {
+ return sprintf("%s[%u]", $match[1], $result[self::INDEX]);
+ }
+ }
+
+ private function parseNth($match) {
+
+ if (in_array(strtolower($match[2]), array('even','odd'))) {
+ $index = strtolower($match[2]) == 'even' ? 0 : 1;
+ return array(self::MULTIPLIER => 2, self::INDEX => $index);
+ // if there is a multiplier
+ } else if (stripos($match[2], 'n') === false) {
+ $index = intval(str_replace(' ', '', $match[2]));
+ return array(self::INDEX => $index);
+ } else {
+
+ if (isset($match[3])) {
+ $multiple_term = str_replace($match[3], '', $match[2]);
+ $index = intval(str_replace(' ', '', $match[3]));
+ } else {
+ $multiple_term = $match[2];
+ $index = 0;
+ }
+
+ $multiplier = str_ireplace('n', '', $multiple_term);
+
+ if (!strlen($multiplier)) $multiplier = 1;
+ elseif ($multiplier == 0) return array(self::INDEX => $index);
+ else $multiplier = intval($multiplier);
+
+ while ($index < 0) $index += abs($multiplier);
+
+ return array(self::MULTIPLIER => $multiplier, self::INDEX => $index);
+ }
+ }
+
+ private function cssStyleDefinitionToArray($style) {
+ $definitions = explode(';',$style);
+ $retArr = array();
+ foreach ($definitions as $def) {
+ if (empty($def) || strpos($def, ':') === false) continue;
+ list($key,$value) = explode(':',$def,2);
+ if (empty($key) || strlen(trim($value)) === 0) continue;
+ $retArr[trim($key)] = trim($value);
+ }
+ return $retArr;
+ }
+} \ No newline at end of file