<?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\Finder;

/**
 * Glob matches globbing patterns against text.
 *
 *   if match_glob("foo.*", "foo.bar") echo "matched\n";
 *
 * // prints foo.bar and foo.baz
 * $regex = glob_to_regex("foo.*");
 * for (array('foo.bar', 'foo.baz', 'foo', 'bar') as $t)
 * {
 *   if (/$regex/) echo "matched: $car\n";
 * }
 *
 * Glob implements glob(3) style matching that can be used to match
 * against text, rather than fetching names from a filesystem.
 *
 * Based on the Perl Text::Glob module.
 *
 * @author Fabien Potencier <fabien@symfony.com> PHP port
 * @author     Richard Clamp <richardc@unixbeard.net> Perl version
 * @copyright  2004-2005 Fabien Potencier <fabien@symfony.com>
 * @copyright  2002 Richard Clamp <richardc@unixbeard.net>
 */
class Glob
{
    /**
     * Returns a regexp which is the equivalent of the glob pattern.
     *
     * @param string  $glob                The glob pattern
     * @param bool    $strictLeadingDot
     * @param bool    $strictWildcardSlash
     *
     * @return string regex The regexp
     */
    public static function toRegex($glob, $strictLeadingDot = true, $strictWildcardSlash = true)
    {
        $firstByte = true;
        $escaping = false;
        $inCurlies = 0;
        $regex = '';
        $sizeGlob = strlen($glob);
        for ($i = 0; $i < $sizeGlob; $i++) {
            $car = $glob[$i];
            if ($firstByte) {
                if ($strictLeadingDot && '.' !== $car) {
                    $regex .= '(?=[^\.])';
                }

                $firstByte = false;
            }

            if ('/' === $car) {
                $firstByte = true;
            }

            if ('.' === $car || '(' === $car || ')' === $car || '|' === $car || '+' === $car || '^' === $car || '$' === $car) {
                $regex .= "\\$car";
            } elseif ('*' === $car) {
                $regex .= $escaping ? '\\*' : ($strictWildcardSlash ? '[^/]*' : '.*');
            } elseif ('?' === $car) {
                $regex .= $escaping ? '\\?' : ($strictWildcardSlash ? '[^/]' : '.');
            } elseif ('{' === $car) {
                $regex .= $escaping ? '\\{' : '(';
                if (!$escaping) {
                    ++$inCurlies;
                }
            } elseif ('}' === $car && $inCurlies) {
                $regex .= $escaping ? '}' : ')';
                if (!$escaping) {
                    --$inCurlies;
                }
            } elseif (',' === $car && $inCurlies) {
                $regex .= $escaping ? ',' : '|';
            } elseif ('\\' === $car) {
                if ($escaping) {
                    $regex .= '\\\\';
                    $escaping = false;
                } else {
                    $escaping = true;
                }

                continue;
            } else {
                $regex .= $car;
            }
            $escaping = false;
        }

        return '#^'.$regex.'$#';
    }
}