<?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\DomCrawler;

/**

 * Link represents an HTML link (an HTML a tag).

 *

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

 *

 * @api

 */

class Link

{

    protected $node;

    protected $method;

    protected $currentUri;

    /**

     * Constructor.

     *

     * @param \DOMNode $node       A \DOMNode instance

     * @param string   $currentUri The URI of the page where the link is embedded (or the base href)

     * @param string   $method     The method to use for the link (get by default)

     *

     * @throws \LogicException if the node is not a link

     *

     * @api

     */

    public function __construct(\DOMNode $node, $currentUri, $method = 'GET')

    {

        if (!in_array(substr($currentUri, 0, 4), array('http', 'file'))) {

            throw new \InvalidArgumentException(sprintf('Current URI must be an absolute URL ("%s").', $currentUri));

        }

        $this->setNode($node);

        $this->method = $method ? strtoupper($method) : null;

        $this->currentUri = $currentUri;

    }

    /**

     * Gets the node associated with this link.

     *

     * @return \DOMNode A \DOMNode instance

     */

    public function getNode()

    {

        return $this->node;

    }

    /**

     * Gets the method associated with this link.

     *

     * @return string The method

     *

     * @api

     */

    public function getMethod()

    {

        return $this->method;

    }

    /**

     * Gets the URI associated with this link.

     *

     * @return string The URI

     *

     * @api

     */

    public function getUri()

    {

        $uri = $this->getRawUri();

        // absolute URL?

        if ('http' === substr($uri, 0, 4)) {

            return $uri;

        }

        // empty URI

        if (!$uri) {

            return $this->currentUri;

        }

        // only an anchor

        if ('#' ===  $uri[0]) {

            $baseUri = $this->currentUri;

            if (false !== $pos = strpos($baseUri, '#')) {

                $baseUri = substr($baseUri, 0, $pos);

            }

            return $baseUri.$uri;

        }

        // only a query string

        if ('?' === $uri[0]) {

            $baseUri = $this->currentUri;

            // remove the query string from the current uri

            if (false !== $pos = strpos($baseUri, '?')) {

                $baseUri = substr($baseUri, 0, $pos);

            }

            return $baseUri.$uri;

        }

        // absolute path

        if ('/' === $uri[0]) {

            return preg_replace('#^(.*?//[^/]+)(?:\/.*)?$#', '$1', $this->currentUri).$uri;

        }

        // relative path

        return substr($this->currentUri, 0, strrpos($this->currentUri, '/') + 1).$uri;

    }

    protected function getRawUri()

    {

        return $this->node->getAttribute('href');

    }

    protected function setNode(\DOMNode $node)

    {

        if ('a' != $node->nodeName) {

            throw new \LogicException(sprintf('Unable to click on a "%s" tag.', $node->nodeName));

        }

        $this->node = $node;

    }

}