Test project for media files management.
<?php
namespace TijsVerkoyen\CssToInlineStyles;
use Symfony\Component\CssSelector\CssSelector;
use Symfony\Component\CssSelector\CssSelectorConverter;
use Symfony\Component\CssSelector\Exception\ExceptionInterface;
use TijsVerkoyen\CssToInlineStyles\Css\Processor;
use TijsVerkoyen\CssToInlineStyles\Css\Property\Processor as PropertyProcessor;
use TijsVerkoyen\CssToInlineStyles\Css\Rule\Processor as RuleProcessor;
class CssToInlineStyles
{
private $cssConverter;
public function __construct()
{
if (class_exists('Symfony\Component\CssSelector\CssSelectorConverter')) {
$this->cssConverter = new CssSelectorConverter();
}
}
/**
* Will inline the $css into the given $html
*
* Remark: if the html contains <style>-tags those will be used, the rules
* in $css will be appended.
*
* @param string $html
* @param string $css
*
* @return string
*/
public function convert($html, $css = null)
{
$document = $this->createDomDocumentFromHtml($html);
$processor = new Processor();
// get all styles from the style-tags
$rules = $processor->getRules(
$processor->getCssFromStyleTags($html)
);
if ($css !== null) {
$rules = $processor->getRules($css, $rules);
}
$document = $this->inline($document, $rules);
return $this->getHtmlFromDocument($document);
}
/**
* Inline the given properties on an given DOMElement
*
* @param \DOMElement $element
* @param Css\Property\Property[] $properties
*
* @return \DOMElement
*/
public function inlineCssOnElement(\DOMElement $element, array $properties)
{
if (empty($properties)) {
return $element;
}
$cssProperties = array();
$inlineProperties = array();
foreach ($this->getInlineStyles($element) as $property) {
$inlineProperties[$property->getName()] = $property;
}
foreach ($properties as $property) {
if (!isset($inlineProperties[$property->getName()])) {
$cssProperties[$property->getName()] = $property;
}
}
$rules = array();
foreach (array_merge($cssProperties, $inlineProperties) as $property) {
$rules[] = $property->toString();
}
$element->setAttribute('style', implode(' ', $rules));
return $element;
}
/**
* Get the current inline styles for a given DOMElement
*
* @param \DOMElement $element
*
* @return Css\Property\Property[]
*/
public function getInlineStyles(\DOMElement $element)
{
$processor = new PropertyProcessor();
return $processor->convertArrayToObjects(
$processor->splitIntoSeparateProperties(
$element->getAttribute('style')
)
);
}
/**
* @param string $html
*
* @return \DOMDocument
*/
protected function createDomDocumentFromHtml($html)
{
$document = new \DOMDocument('1.0', 'UTF-8');
$internalErrors = libxml_use_internal_errors(true);
$document->loadHTML(mb_encode_numericentity($html, [0x80, 0x10FFFF, 0, 0x1FFFFF], 'UTF-8'));
libxml_use_internal_errors($internalErrors);
$document->formatOutput = true;
return $document;
}
/**
* @param \DOMDocument $document
*
* @return string
*/
protected function getHtmlFromDocument(\DOMDocument $document)
{
// retrieve the document element
// we do it this way to preserve the utf-8 encoding
$htmlElement = $document->documentElement;
$html = $document->saveHTML($htmlElement);
$html = trim($html);
// retrieve the doctype
$document->removeChild($htmlElement);
$doctype = $document->saveHTML();
$doctype = trim($doctype);
// if it is the html5 doctype convert it to lowercase
if ($doctype === '<!DOCTYPE html>') {
$doctype = strtolower($doctype);
}
return $doctype."\n".$html;
}
/**
* @param \DOMDocument $document
* @param Css\Rule\Rule[] $rules
*
* @return \DOMDocument
*/
protected function inline(\DOMDocument $document, array $rules)
{
if (empty($rules)) {
return $document;
}
$propertyStorage = new \SplObjectStorage();
$xPath = new \DOMXPath($document);
usort($rules, array(RuleProcessor::class, 'sortOnSpecificity'));
foreach ($rules as $rule) {
try {
if (null !== $this->cssConverter) {
$expression = $this->cssConverter->toXPath($rule->getSelector());
} else {
// Compatibility layer for Symfony 2.7 and older
$expression = CssSelector::toXPath($rule->getSelector());
}
} catch (ExceptionInterface $e) {
continue;
}
$elements = $xPath->query($expression);
if ($elements === false) {
continue;
}
foreach ($elements as $element) {
$propertyStorage[$element] = $this->calculatePropertiesToBeApplied(
$rule->getProperties(),
$propertyStorage->contains($element) ? $propertyStorage[$element] : array()
);
}
}
foreach ($propertyStorage as $element) {
$this->inlineCssOnElement($element, $propertyStorage[$element]);
}
return $document;
}
/**
* Merge the CSS rules to determine the applied properties.
*
* @param Css\Property\Property[] $properties
* @param Css\Property\Property[] $cssProperties existing applied properties indexed by name
*
* @return Css\Property\Property[] updated properties, indexed by name
*/
private function calculatePropertiesToBeApplied(array $properties, array $cssProperties)
{
if (empty($properties)) {
return $cssProperties;
}
foreach ($properties as $property) {
if (isset($cssProperties[$property->getName()])) {
$existingProperty = $cssProperties[$property->getName()];
//skip check to overrule if existing property is important and current is not
if ($existingProperty->isImportant() && !$property->isImportant()) {
continue;
}
//overrule if current property is important and existing is not, else check specificity
$overrule = !$existingProperty->isImportant() && $property->isImportant();
if (!$overrule) {
$overrule = $existingProperty->getOriginalSpecificity()->compareTo($property->getOriginalSpecificity()) <= 0;
}
if ($overrule) {
unset($cssProperties[$property->getName()]);
$cssProperties[$property->getName()] = $property;
}
} else {
$cssProperties[$property->getName()] = $property;
}
}
return $cssProperties;
}
}