<?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\Node;

use Symfony\Component\CssSelector\Exception\ParseException;

/**

 * PseudoNode represents a "selector:ident" node.

 *

 * This component is a port of the Python lxml library,

 * which is copyright Infrae and distributed under the BSD license.

 *

 * @author Fabien Potencier <fabien@symfony.com>

 */

class PseudoNode implements NodeInterface

{

    static protected $unsupported = array(

        'indeterminate', 'first-line', 'first-letter',

        'selection', 'before', 'after', 'link', 'visited',

        'active', 'focus', 'hover',

    );

    protected $element;

    protected $type;

    protected $ident;

    /**

     * Constructor.

     *

     * @param NodeInterface $element The NodeInterface element

     * @param string $type Node type

     * @param string $ident The ident

     * @throws ParseException When incorrect PseudoNode type is given

     */

    public function __construct($element, $type, $ident)

    {

        $this->element = $element;

        if (!in_array($type, array(':', '::'))) {

            throw new ParseException(sprintf('The PseudoNode type can only be : or :: (%s given).', $type));

        }

        $this->type = $type;

        $this->ident = $ident;

    }

    /**

     * {@inheritDoc}

     */

    public function __toString()

    {

        return sprintf('%s[%s%s%s]', __CLASS__, $this->element, $this->type, $this->ident);

    }

    /**

     * {@inheritDoc}

     * @throws ParseException When unsupported or unknown pseudo-class is found

     */

    public function toXpath()

    {

        $elXpath = $this->element->toXpath();

        if (in_array($this->ident, self::$unsupported)) {

            throw new ParseException(sprintf('The pseudo-class %s is unsupported', $this->ident));

        }

        $method = 'xpath_'.str_replace('-', '_', $this->ident);

        if (!method_exists($this, $method)) {

            throw new ParseException(sprintf('The pseudo-class %s is unknown', $this->ident));

        }

        return $this->$method($elXpath);

    }

    /**

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified XPath expression

     */

    protected function xpath_checked($xpath)

    {

        // FIXME: is this really all the elements?

        $xpath->addCondition("(@selected or @checked) and (name(.) = 'input' or name(.) = 'option')");

        return $xpath;

    }

    /**

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified XPath expression

     * @throws ParseException If this element is the root element

     */

    protected function xpath_root($xpath)

    {

        // if this element is the root element

        throw new ParseException();

    }

    /**

     * Marks this XPath expression as the first child.

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     */

    protected function xpath_first_child($xpath)

    {

        $xpath->addStarPrefix();

        $xpath->addNameTest();

        $xpath->addCondition('position() = 1');

        return $xpath;

    }

    /**

     * Sets the XPath  to be the last child.

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     */

    protected function xpath_last_child($xpath)

    {

        $xpath->addStarPrefix();

        $xpath->addNameTest();

        $xpath->addCondition('position() = last()');

        return $xpath;

    }

    /**

     * Sets the XPath expression to be the first of type.

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     */

    protected function xpath_first_of_type($xpath)

    {

        if ($xpath->getElement() == '*') {

            throw new ParseException('*:first-of-type is not implemented');

        }

        $xpath->addStarPrefix();

        $xpath->addCondition('position() = 1');

        return $xpath;

    }

    /**

     * Sets the XPath expression to be the last of type.

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     * @throws ParseException Because *:last-of-type is not implemented

     */

    protected function xpath_last_of_type($xpath)

    {

        if ($xpath->getElement() == '*') {

            throw new ParseException('*:last-of-type is not implemented');

        }

        $xpath->addStarPrefix();

        $xpath->addCondition('position() = last()');

        return $xpath;

    }

    /**

     * Sets the XPath expression to be the only child.

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     */

    protected function xpath_only_child($xpath)

    {

        $xpath->addNameTest();

        $xpath->addStarPrefix();

        $xpath->addCondition('last() = 1');

        return $xpath;

    }

    /**

     * Sets the XPath expression to be only of type.

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     * @throws ParseException Because *:only-of-type is not implemented

     */

    protected function xpath_only_of_type($xpath)

    {

        if ($xpath->getElement() == '*') {

            throw new ParseException('*:only-of-type is not implemented');

        }

        $xpath->addCondition('last() = 1');

        return $xpath;

    }

    /**

     * undocumented function

     *

     * @param XPathExpr $xpath The XPath expression

     * @return XPathExpr The modified expression

     */

    protected function xpath_empty($xpath)

    {

        $xpath->addCondition('not(*) and not(normalize-space())');

        return $xpath;

    }

}