<?php
/**
 * @package     Joomla.Platform
 * @subpackage  Filter
 *
 * @copyright   Copyright (C) 2005 - 2011 Open Source Matters, Inc. All rights reserved.
 * @license     GNU General Public License version 2 or later; see LICENSE
 */

defined('JPATH_PLATFORM') or die;

/**
 * JFilterOutput
 *
 * @static
 * @package     Joomla.Platform
 * @subpackage  Filter
 * @since       11.1
 */
class JFilterOutput
{
    /**
    * Makes an object safe to display in forms
    *
    * Object parameters that are non-string, array, object or start with underscore
    * will be converted
    *
    * @param object An object to be parsed
    * @param int The optional quote style for the htmlspecialchars function
    * @param string|array An optional single field name or array of field names not
    *                   to be parsed (eg, for a textarea)
    * @since   11.1
    */
    public static function objectHTMLSafe(&$mixed, $quote_style=ENT_QUOTES, $exclude_keys='')
    {
        if (is_object($mixed))
        {
            foreach (get_object_vars($mixed) as $k => $v)
            {
                if (is_array($v) || is_object($v) || $v == NULL || substr($k, 1, 1) == '_') {
                    continue;
                }

                if (is_string($exclude_keys) && $k == $exclude_keys) {
                    continue;
                } else if (is_array($exclude_keys) && in_array($k, $exclude_keys)) {
                    continue;
                }

                $mixed->$k = htmlspecialchars($v, $quote_style, 'UTF-8');
            }
        }
    }

    /**
     * This method processes a string and replaces all instances of & with &amp; in links only.
     *
     * @static
     * @param   string  $input  String to process
     * 
     * @return  string  Processed string
     * @since   11.1
     */
    public static function linkXHTMLSafe($input)
    {
        $regex = 'href="([^"]*(&(amp;){0})[^"]*)*?"';
        return preg_replace_callback("#$regex#i", array('JFilterOutput', '_ampReplaceCallback'), $input);
    }

    /**
     * This method processes a string and replaces all accented UTF-8 characters by unaccented
     * ASCII-7 "equivalents", whitespaces are replaced by hyphens and the string is lowercased.
     *
     * @param   string  $input  String to process
     * @return  string  Processed string
     * @since   11.1
     */
    public static function stringURLSafe($string)
    {
        //remove any '-' from the string since they will be used as concatenaters
        $str = str_replace('-', ' ', $string);

        $lang = JFactory::getLanguage();
        $str = $lang->transliterate($str);

        // Convert certain symbols to letter representation
        $str = str_replace(array('&', '"', '<', '>'), array('a', 'q', 'l', 'g'), $str);

        // Lowercase and trim
        $str = trim(strtolower($str));

        // Remove any duplicate whitespace, and ensure all characters are alphanumeric
        $str = preg_replace(array('/\s+/','/[^A-Za-z0-9\-]/'), array('-',''), $str);

        return $str;
    }

    /**
     * This method implements unicode slugs instead of transliteration.
     *
     * @static
     * @param   string  $input  String to process
     * @return  string  Processed string
     * @since   11.1
    */
    public static function stringURLUnicodeSlug($string)
    {
        // Replace double byte whitespaces by single byte (East Asian languages)
        $str = preg_replace('/\xE3\x80\x80/', ' ', $string);


        // Remove any '-' from the string as they will be used as concatenator.
        // Would be great to let the spaces in but only Firefox is friendly with this

        $str = str_replace('-', ' ', $str);

        // Replace forbidden characters by whitespaces
        $str = preg_replace( '#[:\#\*"@+=;!&\.%()\]\/\'\\\\|\[]#',"\x20", $str );

        // Delete all '?'
        $str = str_replace('?', '', $str);

        // Trim white spaces at beginning and end of alias and make lowercase
        $str = trim(JString::strtolower($str));

        // Remove any duplicate whitespace and replace whitespaces by hyphens
        $str =preg_replace('#\x20+#','-', $str);
        
        return $str;
    }

    /**
    * Replaces &amp; with & for xhtml compliance
    *
    * @todo There must be a better way???
    *
    * @static
    * @since   11.1
    */
    public static function ampReplace($text)
    {
        $text = str_replace('&&', '*--*', $text);
        $text = str_replace('&#', '*-*', $text);
        $text = str_replace('&amp;', '&', $text);
        $text = preg_replace('|&(?![\w]+;)|', '&amp;', $text);
        $text = str_replace('*-*', '&#', $text);
        $text = str_replace('*--*', '&&', $text);

        return $text;
    }

    /**
     * Callback method for replacing & with &amp; in a string
     *
     * @param   string  $m  String to process
     * 
     * @return  string  Replaced string
     * @since   11.1
     */
    public static function _ampReplaceCallback($m)
    {
        $rx = '&(?!amp;)';
        
        return preg_replace('#'.$rx.'#', '&amp;', $m[0]);
    }

    /**
    * Cleans text of all formating and scripting code
    */
    public static function cleanText (&$text)
    {
        $text = preg_replace("'<script[^>]*>.*?</script>'si", '', $text);
        $text = preg_replace('/<a\s+.*?href="([^"]+)"[^>]*>([^<]+)<\/a>/is', '\2 (\1)', $text);
        $text = preg_replace('/<!--.+?-->/', '', $text);
        $text = preg_replace('/{.+?}/', '', $text);
        $text = preg_replace('/&nbsp;/', ' ', $text);
        $text = preg_replace('/&amp;/', ' ', $text);
        $text = preg_replace('/&quot;/', ' ', $text);
        $text = strip_tags($text);
        $text = htmlspecialchars($text, ENT_COMPAT, 'UTF-8');

        return $text;
    }

    /**
     * Strip img-tags from string
     */
    public static function stripImages($string)
    {
        return  preg_replace('#(<[/]?img.*>)#U', '', $string);
    }
}