<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\CssSelector\XPath;
use Symfony\Component\CssSelector\Exception\ExpressionErrorException;
use Symfony\Component\CssSelector\Node\FunctionNode;
use Symfony\Component\CssSelector\Node\NodeInterface;
use Symfony\Component\CssSelector\Node\SelectorNode;
use Symfony\Component\CssSelector\Parser\Parser;
use Symfony\Component\CssSelector\Parser\ParserInterface;
/**
* XPath expression translator interface.
*
* This component is a port of the Python cssselector library,
* which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
*
* @author Jean-François Simon <jeanfrancois.simon@sensiolabs.com>
*/
class Translator implements TranslatorInterface
{
/**
* @var ParserInterface
*/
private $mainParser;
/**
* @var ParserInterface[]
*/
private $shortcutParsers = array();
/**
* @var Extension\ExtensionInterface
*/
private $extensions = array();
/**
* @var array
*/
private $nodeTranslators = array();
/**
* @var array
*/
private $combinationTranslators = array();
/**
* @var array
*/
private $functionTranslators = array();
/**
* @var array
*/
private $pseudoClassTranslators = array();
/**
* @var array
*/
private $attributeMatchingTranslators = array();
/**
* Constructor.
*/
public function __construct(ParserInterface $parser = null)
{
$this->mainParser = $parser ?: new Parser();
$this
->registerExtension(new Extension\NodeExtension($this))
->registerExtension(new Extension\CombinationExtension())
->registerExtension(new Extension\FunctionExtension())
->registerExtension(new Extension\PseudoClassExtension())
->registerExtension(new Extension\AttributeMatchingExtension())
;
}
/**
* @param string $element
*
* @return string
*/
public static function getXpathLiteral($element)
{
if (false === strpos($element, "'")) {
return "'".$element."'";
}
if (false === strpos($element, '"')) {
return '"'.$element.'"';
}
$string = $element;
$parts = array();
while (true) {
if (false !== $pos = strpos($string, "'")) {
$parts[] = sprintf("'%s'", substr($string, 0, $pos));
$parts[] = "\"'\"";
$string = substr($string, $pos + 1);
} else {
$parts[] = "'$string'";
break;
}
}
return sprintf('concat(%s)', implode($parts, ', '));
}
/**
* {@inheritdoc}
*/
public function cssToXPath($cssExpr, $prefix = 'descendant-or-self::')
{
$selectors = $this->parseSelectors($cssExpr);
/** @var SelectorNode $selector */
foreach ($selectors as $selector) {
if (null !== $selector->getPseudoElement()) {
throw new ExpressionErrorException('Pseudo-elements are not supported.');
}
}
$translator = $this;
return implode(' | ', array_map(function (SelectorNode $selector) use ($translator, $prefix) {
return $translator->selectorToXPath($selector, $prefix);
}, $selectors));
}
/**
* {@inheritdoc}
*/
public function selectorToXPath(SelectorNode $selector, $prefix = 'descendant-or-self::')
{
return ($prefix ?: '').$this->nodeToXPath($selector);
}
/**
* Registers an extension.
*
* @param Extension\ExtensionInterface $extension
*
* @return Translator
*/
public function registerExtension(Extension\ExtensionInterface $extension)
{
$this->extensions[$extension->getName()] = $extension;
$this->nodeTranslators = array_merge($this->nodeTranslators, $extension->getNodeTranslators());
$this->combinationTranslators = array_merge($this->combinationTranslators, $extension->getCombinationTranslators());
$this->functionTranslators = array_merge($this->functionTranslators, $extension->getFunctionTranslators());
$this->pseudoClassTranslators = array_merge($this->pseudoClassTranslators, $extension->getPseudoClassTranslators());
$this->attributeMatchingTranslators = array_merge($this->attributeMatchingTranslators, $extension->getAttributeMatchingTranslators());
return $this;
}
/**
* @param string $name
*
* @return Extension\ExtensionInterface
*
* @throws ExpressionErrorException
*/
public function getExtension($name)
{
if (!isset($this->extensions[$name])) {
throw new ExpressionErrorException(sprintf('Extension "%s" not registered.', $name));
}
return $this->extensions[$name];
}
/**
* Registers a shortcut parser.
*
* @param ParserInterface $shortcut
*
* @return Translator
*/
public function registerParserShortcut(ParserInterface $shortcut)
{
$this->shortcutParsers[] = $shortcut;
return $this;
}
/**
* @param NodeInterface $node
*
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function nodeToXPath(NodeInterface $node)
{
if (!isset($this->nodeTranslators[$node->getNodeName()])) {
throw new ExpressionErrorException(sprintf('Node "%s" not supported.', $node->getNodeName()));
}
return call_user_func($this->nodeTranslators[$node->getNodeName()], $node);
}
/**
* @param string $combiner
* @param NodeInterface $xpath
* @param NodeInterface $combinedXpath
*
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function addCombination($combiner, NodeInterface $xpath, NodeInterface $combinedXpath)
{
if (!isset($this->combinationTranslators[$combiner])) {
throw new ExpressionErrorException(sprintf('Combiner "%s" not supported.', $combiner));
}
return call_user_func($this->combinationTranslators[$combiner], $this->nodeToXPath($xpath), $this->nodeToXPath($combinedXpath));
}
/**
* @param XPathExpr $xpath
* @param FunctionNode $function
*
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function addFunction(XPathExpr $xpath, FunctionNode $function)
{
if (!isset($this->functionTranslators[$function->getName()])) {
throw new ExpressionErrorException(sprintf('Function "%s" not supported.', $function->getName()));
}
return call_user_func($this->functionTranslators[$function->getName()], $xpath, $function);
}
/**
* @param XPathExpr $xpath
* @param string $pseudoClass
*
* @return XPathExpr
*
* @throws ExpressionErrorException
*/
public function addPseudoClass(XPathExpr $xpath, $pseudoClass)
{
if (!isset($this->pseudoClassTranslators[$pseudoClass])) {
throw new ExpressionErrorException(sprintf('Pseudo-class "%s" not supported.', $pseudoClass));
}
return call_user_func($this->pseudoClassTranslators[$pseudoClass], $xpath);
}
/**
* @param XPathExpr $xpath
* @param string $operator
* @param string $attribute
* @param string $value
*
* @throws ExpressionErrorException
*
* @return XPathExpr
*/
public function addAttributeMatching(XPathExpr $xpath, $operator, $attribute, $value)
{
if (!isset($this->attributeMatchingTranslators[$operator])) {
throw new ExpressionErrorException(sprintf('Attribute matcher operator "%s" not supported.', $operator));
}
return call_user_func($this->attributeMatchingTranslators[$operator], $xpath, $attribute, $value);
}
/**
* @param string $css
*
* @return SelectorNode[]
*/
private function parseSelectors($css)
{
foreach ($this->shortcutParsers as $shortcut) {
$tokens = $shortcut->parse($css);
if (!empty($tokens)) {
return $tokens;
}
}
return $this->mainParser->parse($css);
}
}
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