Chris@0: <?php
Chris@0: 
Chris@0: /*
Chris@0:  * This file is part of the webmozart/path-util package.
Chris@0:  *
Chris@0:  * (c) Bernhard Schussek <bschussek@gmail.com>
Chris@0:  *
Chris@0:  * For the full copyright and license information, please view the LICENSE
Chris@0:  * file that was distributed with this source code.
Chris@0:  */
Chris@0: 
Chris@0: namespace Webmozart\PathUtil;
Chris@0: 
Chris@0: use InvalidArgumentException;
Chris@0: use Webmozart\Assert\Assert;
Chris@0: 
Chris@0: /**
Chris@0:  * Contains utility methods for handling URL strings.
Chris@0:  *
Chris@0:  * The methods in this class are able to deal with URLs.
Chris@0:  *
Chris@0:  * @since  2.3
Chris@0:  *
Chris@0:  * @author Bernhard Schussek <bschussek@gmail.com>
Chris@0:  * @author Claudio Zizza <claudio@budgegeria.de>
Chris@0:  */
Chris@0: final class Url
Chris@0: {
Chris@0:     /**
Chris@0:      * Turns a URL into a relative path.
Chris@0:      *
Chris@0:      * The result is a canonical path. This class is using functionality of Path class.
Chris@0:      *
Chris@0:      * @see Path
Chris@0:      *
Chris@0:      * @param string $url     A URL to make relative.
Chris@0:      * @param string $baseUrl A base URL.
Chris@0:      *
Chris@0:      * @return string
Chris@0:      *
Chris@0:      * @throws InvalidArgumentException If the URL and base URL does
Chris@0:      *                                  not match.
Chris@0:      */
Chris@0:     public static function makeRelative($url, $baseUrl)
Chris@0:     {
Chris@0:         Assert::string($url, 'The URL must be a string. Got: %s');
Chris@0:         Assert::string($baseUrl, 'The base URL must be a string. Got: %s');
Chris@0:         Assert::contains($baseUrl, '://', '%s is not an absolute Url.');
Chris@0: 
Chris@0:         list($baseHost, $basePath) = self::split($baseUrl);
Chris@0: 
Chris@0:         if (false === strpos($url, '://')) {
Chris@0:             if (0 === strpos($url, '/')) {
Chris@0:                 $host = $baseHost;
Chris@0:             } else {
Chris@0:                 $host = '';
Chris@0:             }
Chris@0:             $path = $url;
Chris@0:         } else {
Chris@0:             list($host, $path) = self::split($url);
Chris@0:         }
Chris@0: 
Chris@0:         if ('' !== $host && $host !== $baseHost) {
Chris@0:             throw new InvalidArgumentException(sprintf(
Chris@0:                 'The URL "%s" cannot be made relative to "%s" since their host names are different.',
Chris@0:                 $host,
Chris@0:                 $baseHost
Chris@0:             ));
Chris@0:         }
Chris@0: 
Chris@0:         return Path::makeRelative($path, $basePath);
Chris@0:     }
Chris@0: 
Chris@0:     /**
Chris@0:      * Splits a URL into its host and the path.
Chris@0:      *
Chris@0:      * ```php
Chris@0:      * list ($root, $path) = Path::split("http://example.com/webmozart")
Chris@0:      * // => array("http://example.com", "/webmozart")
Chris@0:      *
Chris@0:      * list ($root, $path) = Path::split("http://example.com")
Chris@0:      * // => array("http://example.com", "")
Chris@0:      * ```
Chris@0:      *
Chris@0:      * @param string $url The URL to split.
Chris@0:      *
Chris@0:      * @return string[] An array with the host and the path of the URL.
Chris@0:      *
Chris@0:      * @throws InvalidArgumentException If $url is not a URL.
Chris@0:      */
Chris@0:     private static function split($url)
Chris@0:     {
Chris@0:         $pos = strpos($url, '://');
Chris@0:         $scheme = substr($url, 0, $pos + 3);
Chris@0:         $url = substr($url, $pos + 3);
Chris@0: 
Chris@0:         if (false !== ($pos = strpos($url, '/'))) {
Chris@0:             $host = substr($url, 0, $pos);
Chris@0:             $url = substr($url, $pos);
Chris@0:         } else {
Chris@0:             // No path, only host
Chris@0:             $host = $url;
Chris@0:             $url = '/';
Chris@0:         }
Chris@0: 
Chris@0:         // At this point, we have $scheme, $host and $path
Chris@0:         $root = $scheme.$host;
Chris@0: 
Chris@0:         return array($root, $url);
Chris@0:     }
Chris@0: }