File: /web/data/blog.tbbbearing.com/wp-content/plugins/wp-mailer/mailer/emogrifier.php
<?php
namespace Pelago;
/**
* This class provides functions for converting CSS styles into inline style attributes in your HTML code.
*
* For more information, please see the README.md file.
*
* @version 0.1.1
*
* @author Cameron Brooks
* @author Jaime Prado
* @author Roman Ožana <ozana@omdesign.cz>
*/
class Emogrifier
{
/**
* @var string
*/
const ENCODING = 'UTF-8';
/**
* @var int
*/
const CACHE_KEY_CSS = 0;
/**
* @var int
*/
const CACHE_KEY_SELECTOR = 1;
/**
* @var int
*/
const CACHE_KEY_XPATH = 2;
/**
* @var int
*/
const CACHE_KEY_CSS_DECLARATION_BLOCK = 3;
/**
* for calculating nth-of-type and nth-child selectors
*
* @var int
*/
const INDEX = 0;
/**
* for calculating nth-of-type and nth-child selectors
*
* @var int
*/
const MULTIPLIER = 1;
/**
* @var string
*/
const ID_ATTRIBUTE_MATCHER = '/(\\w+)?\\#([\\w\\-]+)/';
/**
* @var string
*/
const CLASS_ATTRIBUTE_MATCHER = '/(\\w+|[\\*\\]])?((\\.[\\w\\-]+)+)/';
/**
* @var string
*/
private $html = '';
/**
* @var string
*/
private $css = '';
/**
* @var string[]
*/
private $unprocessableHtmlTags = array('wbr');
/**
* @var array[]
*/
private $caches = array(
self::CACHE_KEY_CSS => array(),
self::CACHE_KEY_SELECTOR => array(),
self::CACHE_KEY_XPATH => array(),
self::CACHE_KEY_CSS_DECLARATION_BLOCK => array(),
);
/**
* the visited nodes with the XPath paths as array keys
*
* @var \DOMNode[]
*/
private $visitedNodes = array();
/**
* the styles to apply to the nodes with the XPath paths as array keys for the outer array
* and the attribute names/values as key/value pairs for the inner array
*
* @var array[]
*/
private $styleAttributesForNodes = array();
/**
* Determines whether the "style" attributes of tags in the the HTML passed to this class should be preserved.
* If set to false, the value of the style attributes will be discarded.
*
* @var bool
*/
private $isInlineStyleAttributesParsingEnabled = true;
/**
* Determines whether the <style> blocks in the HTML passed to this class should be parsed.
*
* If set to true, the <style> blocks will be removed from the HTML and their contents will be applied to the HTML
* via inline styles.
*
* If set to false, the <style> blocks will be left as they are in the HTML.
*
* @var bool
*/
private $isStyleBlocksParsingEnabled = true;
/**
* Determines whether elements with the `display: none` property are
* removed from the DOM.
*
* @var bool
*/
private $shouldKeepInvisibleNodes = true;
/**
* 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.
*
* @var bool
*/
public $preserveEncoding = false;
/**
* The constructor.
*
* @param string $html the HTML to emogrify, must be UTF-8-encoded
* @param string $css the CSS to merge, must be UTF-8-encoded
*/
public function __construct($html = '', $css = '')
{
$this->setHtml($html);
$this->setCss($css);
}
/**
* The destructor.
*/
public function __destruct()
{
$this->purgeVisitedNodes();
}
/**
* Sets the HTML to emogrify.
*
* @param string $html the HTML to emogrify, must be UTF-8-encoded
*
* @return void
*/
public function setHtml($html)
{
$this->html = $html;
}
/**
* Sets the CSS to merge with the HTML.
*
* @param string $css the CSS to merge, must be UTF-8-encoded
*
* @return void
*/
public function setCss($css)
{
$this->css = $css;
}
/**
* Applies the CSS you submit to the HTML you submit.
*
* This method places the CSS inline.
*
* @return string
*
* @throws \BadMethodCallException
*/
public function emogrify()
{
if ($this->html === '') {
throw new \BadMethodCallException('Please set some HTML first before calling emogrify.', 1390393096);
}
$xmlDocument = $this->createXmlDocument();
$xpath = new \DOMXPath($xmlDocument);
$this->clearAllCaches();
// Before be begin processing the CSS file, parse the document and normalize all existing CSS attributes.
// This 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.
$this->purgeVisitedNodes();
$nodesWithStyleAttributes = $xpath->query('//*[@style]');
if ($nodesWithStyleAttributes !== false) {
/** @var \DOMElement $node */
foreach ($nodesWithStyleAttributes as $node) {
if ($this->isInlineStyleAttributesParsingEnabled) {
$this->normalizeStyleAttributes($node);
} else {
$node->removeAttribute('style');
}
}
}
// 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)
$allCss = $this->css;
if ($this->isStyleBlocksParsingEnabled) {
$allCss .= $this->getCssFromAllStyleNodes($xpath);
}
$cssParts = $this->splitCssAndMediaQuery($allCss);
$cssKey = md5($cssParts['css']);
if (!isset($this->caches[self::CACHE_KEY_CSS][$cssKey])) {
// process the CSS file for selectors and definitions
preg_match_all('/(?:^|[\\s^{}]*)([^{]+){([^}]*)}/mis', $cssParts['css'], $matches, PREG_SET_ORDER);
$allSelectors = array();
foreach ($matches as $key => $selectorString) {
// if there is a blank definition, skip
if (!strlen(trim($selectorString[2]))) {
continue;
}
// else split by commas and duplicate attributes so we can sort by selector precedence
$selectors = explode(',', $selectorString[1]);
foreach ($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;
}
$allSelectors[] = array('selector' => trim($selector),
'attributes' => trim($selectorString[2]),
// keep track of where it appears in the file, since order is important
'line' => $key,
);
}
}
// now sort the selectors by precedence
usort($allSelectors, array($this,'sortBySelectorPrecedence'));
$this->caches[self::CACHE_KEY_CSS][$cssKey] = $allSelectors;
}
foreach ($this->caches[self::CACHE_KEY_CSS][$cssKey] as $value) {
// query the body for the xpath selector
$nodesMatchingCssSelectors = $xpath->query($this->translateCssToXpath($value['selector']));
/** @var \DOMElement $node */
foreach ($nodesMatchingCssSelectors 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
$oldStyleDeclarations = $this->parseCssDeclarationBlock($node->getAttribute('style'));
} else {
$oldStyleDeclarations = array();
}
$newStyleDeclarations = $this->parseCssDeclarationBlock($value['attributes']);
$node->setAttribute(
'style',
$this->generateStyleStringFromDeclarationsArrays($oldStyleDeclarations, $newStyleDeclarations)
);
}
}
if ($this->isInlineStyleAttributesParsingEnabled) {
$this->fillStyleAttributesWithMergedStyles();
}
if ($this->shouldKeepInvisibleNodes) {
$this->removeInvisibleNodes($xpath);
}
$this->copyCssWithMediaToStyleNode($cssParts, $xmlDocument);
if ($this->preserveEncoding) {
return mb_convert_encoding($xmlDocument->saveHTML(), self::ENCODING, 'HTML-ENTITIES');
} else {
return $xmlDocument->saveHTML();
}
}
/**
* Disables the parsing of inline styles.
*
* @return void
*/
public function disableInlineStyleAttributesParsing()
{
$this->isInlineStyleAttributesParsingEnabled = false;
}
/**
* Disables the parsing of <style> blocks.
*
* @return void
*/
public function disableStyleBlocksParsing()
{
$this->isStyleBlocksParsingEnabled = false;
}
/**
* Disables the removal of elements with `display: none` properties.
*
* @return void
*/
public function disableInvisibleNodeRemoval()
{
$this->shouldKeepInvisibleNodes = false;
}
/**
* Clears all caches.
*
* @return void
*/
private function clearAllCaches()
{
$this->clearCache(self::CACHE_KEY_CSS);
$this->clearCache(self::CACHE_KEY_SELECTOR);
$this->clearCache(self::CACHE_KEY_XPATH);
$this->clearCache(self::CACHE_KEY_CSS_DECLARATION_BLOCK);
}
/**
* Clears a single cache by key.
*
* @param int $key the cache key, must be CACHE_KEY_CSS, CACHE_KEY_SELECTOR, CACHE_KEY_XPATH
* or CACHE_KEY_CSS_DECLARATION_BLOCK
*
* @return void
*
* @throws \InvalidArgumentException
*/
private function clearCache($key)
{
$allowedCacheKeys = array(
self::CACHE_KEY_CSS,
self::CACHE_KEY_SELECTOR,
self::CACHE_KEY_XPATH,
self::CACHE_KEY_CSS_DECLARATION_BLOCK,
);
if (!in_array($key, $allowedCacheKeys, true)) {
throw new \InvalidArgumentException('Invalid cache key: ' . $key, 1391822035);
}
$this->caches[$key] = array();
}
/**
* Purges the visited nodes.
*
* @return void
*/
private function purgeVisitedNodes()
{
$this->visitedNodes = array();
$this->styleAttributesForNodes = array();
}
/**
* Marks a tag for removal.
*
* There are some HTML tags that DOMDocument cannot process, and it will throw an error if it encounters them.
* In particular, DOMDocument will complain if you try to use HTML5 tags in an XHTML document.
*
* Note: The tags will not be removed if they have any content.
*
* @param string $tagName the tag name, e.g., "p"
*
* @return void
*/
public function addUnprocessableHtmlTag($tagName)
{
$this->unprocessableHtmlTags[] = $tagName;
}
/**
* Drops a tag from the removal list.
*
* @param string $tagName the tag name, e.g., "p"
*
* @return void
*/
public function removeUnprocessableHtmlTag($tagName)
{
$key = array_search($tagName, $this->unprocessableHtmlTags, true);
if ($key !== false) {
unset($this->unprocessableHtmlTags[$key]);
}
}
/**
* 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.
*
* @param \DOMXPath $xpath
*
* @return void
*/
private function removeInvisibleNodes(\DOMXPath $xpath)
{
$nodesWithStyleDisplayNone = $xpath->query(
'//*[contains(translate(translate(@style," ",""),"NOE","noe"),"display:none")]'
);
if ($nodesWithStyleDisplayNone->length === 0) {
return;
}
// 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
/** @var \DOMNode $node */
foreach ($nodesWithStyleDisplayNone as $node) {
if ($node->parentNode && is_callable(array($node->parentNode, 'removeChild'))) {
$node->parentNode->removeChild($node);
}
}
}
/**
* Normalizes the value of the "style" attribute and saves it.
*
* @param \DOMElement $node
*
* @return void
*/
private function normalizeStyleAttributes(\DOMElement $node)
{
$normalizedOriginalStyle = preg_replace_callback(
'/[A-z\\-]+(?=\\:)/S',
function (array $m) {
return strtolower($m[0]);
},
$node->getAttribute('style')
);
// in order to not overwrite existing style attributes in the HTML, we
// have to save the original HTML styles
$nodePath = $node->getNodePath();
if (!isset($this->styleAttributesForNodes[$nodePath])) {
$this->styleAttributesForNodes[$nodePath] = $this->parseCssDeclarationBlock($normalizedOriginalStyle);
$this->visitedNodes[$nodePath] = $node;
}
$node->setAttribute('style', $normalizedOriginalStyle);
}
/**
* Merges styles from styles attributes and style nodes and applies them to the attribute nodes
*
* return @void
*/
private function fillStyleAttributesWithMergedStyles()
{
foreach ($this->styleAttributesForNodes as $nodePath => $styleAttributesForNode) {
$node = $this->visitedNodes[$nodePath];
$currentStyleAttributes = $this->parseCssDeclarationBlock($node->getAttribute('style'));
$node->setAttribute(
'style',
$this->generateStyleStringFromDeclarationsArrays(
$currentStyleAttributes,
$styleAttributesForNode
)
);
}
}
/**
* This method merges old or existing name/value array with new name/value array
* and then generates a string of the combined style suitable for placing inline.
* This becomes the single point for CSS string generation allowing for consistent
* CSS output no matter where the CSS originally came from.
*
* @param string[] $oldStyles
* @param string[] $newStyles
*
* @return string
*/
private function generateStyleStringFromDeclarationsArrays(array $oldStyles, array $newStyles)
{
$combinedStyles = array_merge($oldStyles, $newStyles);
$style = '';
foreach ($combinedStyles as $attributeName => $attributeValue) {
$style .= (strtolower(trim($attributeName)) . ': ' . trim($attributeValue) . '; ');
}
return trim($style);
}
/**
* Copies the media part from CSS array parts to $xmlDocument.
*
* @param string[] $cssParts
* @param \DOMDocument $xmlDocument
*
* @return void
*/
public function copyCssWithMediaToStyleNode(array $cssParts, \DOMDocument $xmlDocument)
{
if (isset($cssParts['media']) && $cssParts['media'] !== '') {
$this->addStyleElementToDocument($xmlDocument, $cssParts['media']);
}
}
/**
* Returns CSS content.
*
* @param \DOMXPath $xpath
*
* @return string
*/
private function getCssFromAllStyleNodes(\DOMXPath $xpath)
{
$styleNodes = $xpath->query('//style');
if ($styleNodes === false) {
return '';
}
$css = '';
/** @var \DOMNode $styleNode */
foreach ($styleNodes as $styleNode) {
$css .= "\n\n" . $styleNode->nodeValue;
$styleNode->parentNode->removeChild($styleNode);
}
return $css;
}
/**
* Adds a style element with $css to $document.
*
* This method is protected to allow overriding.
*
* @see https://github.com/jjriv/emogrifier/issues/103
*
* @param \DOMDocument $document
* @param string $css
*
* @return void
*/
protected function addStyleElementToDocument(\DOMDocument $document, $css)
{
$styleElement = $document->createElement('style', $css);
$styleAttribute = $document->createAttribute('type');
$styleAttribute->value = 'text/css';
$styleElement->appendChild($styleAttribute);
$head = $this->getOrCreateHeadElement($document);
$head->appendChild($styleElement);
}
/**
* Returns the existing or creates a new head element in $document.
*
* @param \DOMDocument $document
*
* @return \DOMNode the head element
*/
private function getOrCreateHeadElement(\DOMDocument $document)
{
$head = $document->getElementsByTagName('head')->item(0);
if ($head === null) {
$head = $document->createElement('head');
$html = $document->getElementsByTagName('html')->item(0);
$html->insertBefore($head, $document->getElementsByTagName('body')->item(0));
}
return $head;
}
/**
* Splits input CSS code to an array where:
*
* - key "css" will be contains clean CSS code
* - key "media" will be contains all valuable media queries
*
* Example:
*
* The CSS code
*
* "@import "file.css"; h1 { color:red; } @media { h1 {}} @media tv { h1 {}}"
*
* will be parsed into the following array:
*
* "css" => "h1 { color:red; }"
* "media" => "@media { h1 {}}"
*
* @param string $css
*
* @return string[]
*/
private function splitCssAndMediaQuery($css)
{
$media = '';
$css = preg_replace_callback(
'#@media\\s+(?:only\\s)?(?:[\\s{\\(]|screen|all)\\s?[^{]+{.*}\\s*}\\s*#misU',
function ($matches) use (&$media) {
$media .= $matches[0];
},
$css
);
// filter the CSS
$search = array(
// get rid of css comment code
'/\\/\\*.*\\*\\//sU',
// strip out any import directives
'/^\\s*@import\\s[^;]+;/misU',
// strip remains media enclosures
'/^\\s*@media\\s[^{]+{(.*)}\\s*}\\s/misU',
);
$replace = array(
'',
'',
'',
);
// clean CSS before output
$css = preg_replace($search, $replace, $css);
return array('css' => $css, 'media' => $media);
}
/**
* Creates a DOMDocument instance with the current HTML.
*
* @return \DOMDocument
*/
private function createXmlDocument()
{
$xmlDocument = new \DOMDocument;
$xmlDocument->encoding = self::ENCODING;
$xmlDocument->strictErrorChecking = false;
$xmlDocument->formatOutput = true;
$libXmlState = libxml_use_internal_errors(true);
$xmlDocument->loadHTML($this->getUnifiedHtml());
libxml_clear_errors();
libxml_use_internal_errors($libXmlState);
$xmlDocument->normalizeDocument();
return $xmlDocument;
}
/**
* Returns the HTML with the non-ASCII characters converts into HTML entities and the unprocessable
* HTML tags removed.
*
* @return string the unified HTML
*
* @throws \BadMethodCallException
*/
private function getUnifiedHtml()
{
if (!empty($this->unprocessableHtmlTags)) {
$unprocessableHtmlTags = implode('|', $this->unprocessableHtmlTags);
$bodyWithoutUnprocessableTags = preg_replace(
'/<\\/?(' . $unprocessableHtmlTags . ')[^>]*>/i',
'',
$this->html
);
} else {
$bodyWithoutUnprocessableTags = $this->html;
}
return mb_convert_encoding($bodyWithoutUnprocessableTags, 'HTML-ENTITIES', self::ENCODING);
}
/**
* @param string[] $a
* @param string[] $b
*
* @return int
*/
private function sortBySelectorPrecedence(array $a, array $b)
{
$precedenceA = $this->getCssSelectorPrecedence($a['selector']);
$precedenceB = $this->getCssSelectorPrecedence($b['selector']);
// We want these sorted in ascending order so selectors with lesser precedence get processed first and
// selectors with greater precedence get sorted last.
$precedenceForEquals = ($a['line'] < $b['line'] ? -1 : 1);
$precedenceForNotEquals = ($precedenceA < $precedenceB ? -1 : 1);
return ($precedenceA === $precedenceB) ? $precedenceForEquals : $precedenceForNotEquals;
}
/**
* @param string $selector
*
* @return int
*/
private function getCssSelectorPrecedence($selector)
{
$selectorKey = md5($selector);
if (!isset($this->caches[self::CACHE_KEY_SELECTOR][$selectorKey])) {
$precedence = 0;
$value = 100;
// ids: worth 100, classes: worth 10, elements: worth 1
$search = array('\\#','\\.','');
foreach ($search as $s) {
if (trim($selector) === '') {
break;
}
$number = 0;
$selector = preg_replace('/' . $s . '\\w+/', '', $selector, -1, $number);
$precedence += ($value * $number);
$value /= 10;
}
$this->caches[self::CACHE_KEY_SELECTOR][$selectorKey] = $precedence;
}
return $this->caches[self::CACHE_KEY_SELECTOR][$selectorKey];
}
/**
* Right now, we support all CSS 1 selectors and most CSS2/3 selectors.
*
* @see http://plasmasturm.org/log/444/
*
* @param string $paramCssSelector
*
* @return string
*/
private function translateCssToXpath($paramCssSelector)
{
$cssSelector = ' ' . $paramCssSelector . ' ';
$cssSelector = preg_replace_callback(
'/\\s+\\w+\\s+/',
function (array $matches) {
return strtolower($matches[0]);
},
$cssSelector
);
$cssSelector = trim($cssSelector);
$xpathKey = md5($cssSelector);
if (!isset($this->caches[self::CACHE_KEY_XPATH][$xpathKey])) {
// returns an Xpath selector
$search = array(
// Matches any element that is a child of parent.
'/\\s+>\\s+/',
// Matches any element that is an adjacent sibling.
'/\\s+\\+\\s+/',
// Matches any element that is a descendant of an parent element element.
'/\\s+/',
// first-child pseudo-selector
'/([^\\/]+):first-child/i',
// last-child pseudo-selector
'/([^\\/]+):last-child/i',
// Matches attribute only selector
'/^\\[(\\w+)\\]/',
// Matches element with attribute
'/(\\w)\\[(\\w+)\\]/',
// Matches element with EXACT attribute
'/(\\w)\\[(\\w+)\\=[\'"]?(\\w+)[\'"]?\\]/',
);
$replace = array(
'/',
'/following-sibling::*[1]/self::',
'//',
'*[1]/self::\\1',
'*[last()]/self::\\1',
'*[@\\1]',
'\\1[@\\2]',
'\\1[@\\2="\\3"]',
);
$cssSelector = '//' . preg_replace($search, $replace, $cssSelector);
$cssSelector = preg_replace_callback(
self::ID_ATTRIBUTE_MATCHER,
array($this, 'matchIdAttributes'),
$cssSelector
);
$cssSelector = preg_replace_callback(
self::CLASS_ATTRIBUTE_MATCHER,
array($this, 'matchClassAttributes'),
$cssSelector
);
// Advanced selectors are going to require a bit more advanced emogrification.
// When we required PHP 5.3, we could do this with closures.
$cssSelector = preg_replace_callback(
'/([^\\/]+):nth-child\\(\\s*(odd|even|[+\\-]?\\d|[+\\-]?\\d?n(\\s*[+\\-]\\s*\\d)?)\\s*\\)/i',
array($this, 'translateNthChild'),
$cssSelector
);
$cssSelector = preg_replace_callback(
'/([^\\/]+):nth-of-type\\(\s*(odd|even|[+\\-]?\\d|[+\\-]?\\d?n(\\s*[+\\-]\\s*\\d)?)\\s*\\)/i',
array($this, 'translateNthOfType'),
$cssSelector
);
$this->caches[self::CACHE_KEY_SELECTOR][$xpathKey] = $cssSelector;
}
return $this->caches[self::CACHE_KEY_SELECTOR][$xpathKey];
}
/**
* @param string[] $match
*
* @return string
*/
private function matchIdAttributes(array $match)
{
return (strlen($match[1]) ? $match[1] : '*') . '[@id="' . $match[2] . '"]';
}
/**
* @param string[] $match
*
* @return string
*/
private function matchClassAttributes(array $match)
{
return (strlen($match[1]) ? $match[1] : '*') . '[contains(concat(" ",@class," "),concat(" ","' .
implode(
'"," "))][contains(concat(" ",@class," "),concat(" ","',
explode('.', substr($match[2], 1))
) . '"," "))]';
}
/**
* @param string[] $match
*
* @return string
*/
private function translateNthChild(array $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]);
}
}
/**
* @param string[] $match
*
* @return string
*/
private function translateNthOfType(array $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]);
}
}
/**
* @param string[] $match
*
* @return int[]
*/
private function parseNth(array $match)
{
if (in_array(strtolower($match[2]), array('even','odd'), true)) {
$index = strtolower($match[2]) === 'even' ? 0 : 1;
return array(self::MULTIPLIER => 2, self::INDEX => $index);
} elseif (stripos($match[2], 'n') === false) {
// if there is a multiplier
$index = (int) str_replace(' ', '', $match[2]);
return array(self::INDEX => $index);
} else {
if (isset($match[3])) {
$multipleTerm = str_replace($match[3], '', $match[2]);
$index = (int) str_replace(' ', '', $match[3]);
} else {
$multipleTerm = $match[2];
$index = 0;
}
$multiplier = (int) str_ireplace('n', '', $multipleTerm);
if (!strlen($multiplier)) {
$multiplier = 1;
} elseif ($multiplier === 0) {
return array(self::INDEX => $index);
} else {
$multiplier = (int) $multiplier;
}
while ($index < 0) {
$index += abs($multiplier);
}
return array(self::MULTIPLIER => $multiplier, self::INDEX => $index);
}
}
/**
* Parses a CSS declaration block into property name/value pairs.
*
* Example:
*
* The declaration block
*
* "color: #000; font-weight: bold;"
*
* will be parsed into the following array:
*
* "color" => "#000"
* "font-weight" => "bold"
*
* @param string $cssDeclarationBlock the CSS declaration block without the curly braces, may be empty
*
* @return string[]
* the CSS declarations with the property names as array keys and the property values as array values
*/
private function parseCssDeclarationBlock($cssDeclarationBlock)
{
if (isset($this->caches[self::CACHE_KEY_CSS_DECLARATION_BLOCK][$cssDeclarationBlock])) {
return $this->caches[self::CACHE_KEY_CSS_DECLARATION_BLOCK][$cssDeclarationBlock];
}
$properties = array();
$declarations = explode(';', $cssDeclarationBlock);
foreach ($declarations as $declaration) {
$matches = array();
if (!preg_match('/ *([A-Za-z\\-]+) *: *([^;]+) */', $declaration, $matches)) {
continue;
}
$propertyName = strtolower($matches[1]);
$propertyValue = $matches[2];
$properties[$propertyName] = $propertyValue;
}
$this->caches[self::CACHE_KEY_CSS_DECLARATION_BLOCK][$cssDeclarationBlock] = $properties;
return $properties;
}
}