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/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier &lt;fabien@symfony.com&gt;
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\CssSelector\XPath\Extension;

use Symfony\Component\CssSelector\Exception\ExpressionErrorException;
use Symfony\Component\CssSelector\Node\FunctionNode;
use Symfony\Component\CssSelector\XPath\Translator;
use Symfony\Component\CssSelector\XPath\XPathExpr;

/**
 * XPath expression translator HTML extension.
 *
 * This component is a port of the Python cssselect library,
 * which is copyright Ian Bicking, @see https://github.com/SimonSapin/cssselect.
 *
 * @author Jean-François Simon &lt;jeanfrancois.simon@sensiolabs.com&gt;
 *
 * @internal
 */
class HtmlExtension extends AbstractExtension
{
    public function __construct(Translator $translator)
    {
        $translator
            -&gt;getExtension('node')
            -&gt;setFlag(NodeExtension::ELEMENT_NAME_IN_LOWER_CASE, true)
            -&gt;setFlag(NodeExtension::ATTRIBUTE_NAME_IN_LOWER_CASE, true);
    }

    /**
     * {@inheritdoc}
     */
    public function getPseudoClassTranslators(): array
    {
        return [
            'checked' =&gt; [$this, 'translateChecked'],
            'link' =&gt; [$this, 'translateLink'],
            'disabled' =&gt; [$this, 'translateDisabled'],
            'enabled' =&gt; [$this, 'translateEnabled'],
            'selected' =&gt; [$this, 'translateSelected'],
            'invalid' =&gt; [$this, 'translateInvalid'],
            'hover' =&gt; [$this, 'translateHover'],
            'visited' =&gt; [$this, 'translateVisited'],
        ];
    }

    /**
     * {@inheritdoc}
     */
    public function getFunctionTranslators(): array
    {
        return [
            'lang' =&gt; [$this, 'translateLang'],
        ];
    }

    public function translateChecked(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition(
            '(@checked '
            .&quot;and (name(.) = 'input' or name(.) = 'command')&quot;
            .&quot;and (@type = 'checkbox' or @type = 'radio'))&quot;
        );
    }

    public function translateLink(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition(&quot;@href and (name(.) = 'a' or name(.) = 'link' or name(.) = 'area')&quot;);
    }

    public function translateDisabled(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition(
            '('
                .'@disabled and'
                .'('
                    .&quot;(name(.) = 'input' and @type != 'hidden')&quot;
                    .&quot; or name(.) = 'button'&quot;
                    .&quot; or name(.) = 'select'&quot;
                    .&quot; or name(.) = 'textarea'&quot;
                    .&quot; or name(.) = 'command'&quot;
                    .&quot; or name(.) = 'fieldset'&quot;
                    .&quot; or name(.) = 'optgroup'&quot;
                    .&quot; or name(.) = 'option'&quot;
                .')'
            .') or ('
                .&quot;(name(.) = 'input' and @type != 'hidden')&quot;
                .&quot; or name(.) = 'button'&quot;
                .&quot; or name(.) = 'select'&quot;
                .&quot; or name(.) = 'textarea'&quot;
            .')'
            .' and ancestor::fieldset[@disabled]'
        );
        // todo: in the second half, add &quot;and is not a descendant of that fieldset element's first legend element child, if any.&quot;
    }

    public function translateEnabled(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition(
            '('
                .'@href and ('
                    .&quot;name(.) = 'a'&quot;
                    .&quot; or name(.) = 'link'&quot;
                    .&quot; or name(.) = 'area'&quot;
                .')'
            .') or ('
                .'('
                    .&quot;name(.) = 'command'&quot;
                    .&quot; or name(.) = 'fieldset'&quot;
                    .&quot; or name(.) = 'optgroup'&quot;
                .')'
                .' and not(@disabled)'
            .') or ('
                .'('
                    .&quot;(name(.) = 'input' and @type != 'hidden')&quot;
                    .&quot; or name(.) = 'button'&quot;
                    .&quot; or name(.) = 'select'&quot;
                    .&quot; or name(.) = 'textarea'&quot;
                    .&quot; or name(.) = 'keygen'&quot;
                .')'
                .' and not (@disabled or ancestor::fieldset[@disabled])'
            .') or ('
                .&quot;name(.) = 'option' and not(&quot;
                    .'@disabled or ancestor::optgroup[@disabled]'
                .')'
            .')'
        );
    }

    /**
     * @throws ExpressionErrorException
     */
    public function translateLang(XPathExpr $xpath, FunctionNode $function): XPathExpr
    {
        $arguments = $function-&gt;getArguments();
        foreach ($arguments as $token) {
            if (!($token-&gt;isString() || $token-&gt;isIdentifier())) {
                throw new ExpressionErrorException('Expected a single string or identifier for :lang(), got '.implode(', ', $arguments));
            }
        }

        return $xpath-&gt;addCondition(sprintf(
            'ancestor-or-self::*[@lang][1][starts-with(concat('
            .&quot;translate(@%s, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ', 'abcdefghijklmnopqrstuvwxyz'), '-')&quot;
            .', %s)]',
            'lang',
            Translator::getXpathLiteral(strtolower($arguments[0]-&gt;getValue()).'-')
        ));
    }

    public function translateSelected(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition(&quot;(@selected and name(.) = 'option')&quot;);
    }

    public function translateInvalid(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition('0');
    }

    public function translateHover(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition('0');
    }

    public function translateVisited(XPathExpr $xpath): XPathExpr
    {
        return $xpath-&gt;addCondition('0');
    }

    /**
     * {@inheritdoc}
     */
    public function getName(): string
    {
        return 'html';
    }
}
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