smarty/plugins/shared.mb_str_replace.php

<?php
/**
 * Smarty shared plugin
 *
 * @package    Smarty
 * @subpackage PluginsShared
 */

/**
 * Multibyte string replace
 *
 * @param string|string[] $search  the string to be searched
 * @param string|string[] $replace the replacement string
 * @param string          $subject the source string
 * @param int             &$count  number of matches found
 *
 * @return string replaced string
 * @author Rodney Rehm
 */
function smarty_mb_str_replace($search, $replace, $subject, &$count = 0)
{
    if (!is_array($search) && is_array($replace)) {
        return false;
    }
    if (is_array($subject)) {
        // call mb_replace for each single string in $subject
        foreach ($subject as &$string) {
            $string = smarty_mb_str_replace($search, $replace, $string, $c);
            $count += $c;
        }
    } elseif (is_array($search)) {
        if (!is_array($replace)) {
            foreach ($search as &$string) {
                $subject = smarty_mb_str_replace($string, $replace, $subject, $c);
                $count += $c;
            }
        } else {
            $n = max(count($search), count($replace));
            while ($n--) {
                $subject = smarty_mb_str_replace(current($search), current($replace), $subject, $c);
                $count += $c;
                next($search);
                next($replace);
            }
        }
    } else {
        $mb_reg_charset = mb_regex_encoding();
        // Check if mbstring regex is using UTF-8
        $reg_is_unicode = !strcasecmp($mb_reg_charset, "UTF-8");
        if(!$reg_is_unicode) {
            // ...and set to UTF-8 if not
            mb_regex_encoding("UTF-8");
        }

        // See if charset used by Smarty is matching one used by regex...
        $current_charset = mb_regex_encoding();
        $convert_result = (bool)strcasecmp(\Smarty\Smarty::$_CHARSET, $current_charset);
        if($convert_result) {
            // ...convert to it if not.
            $subject = mb_convert_encoding($subject, $current_charset, \Smarty\Smarty::$_CHARSET);
            $search = mb_convert_encoding($search, $current_charset, \Smarty\Smarty::$_CHARSET);
            $replace = mb_convert_encoding($replace, $current_charset, \Smarty\Smarty::$_CHARSET);
        }

        $parts = mb_split(preg_quote($search), $subject ?? "") ?: array();
        // If original regex encoding was not unicode...
        if(!$reg_is_unicode) {
            // ...restore original regex encoding to avoid breaking the system.
            mb_regex_encoding($mb_reg_charset);
        }
        if($parts === false) {
            // This exception is thrown if call to mb_split failed.
            // Usually it happens, when $search or $replace are not valid for given mb_regex_encoding().
            // There may be other cases for it to fail, please file an issue if you find a reproducible one.
            throw new SmartyException("Source string is not a valid $current_charset sequence (probably)");
        }

        $count = count($parts) - 1;
        $subject = implode($replace, $parts);
        // Convert results back to charset used by Smarty, if needed.
        if($convert_result) {
            $subject = mb_convert_encoding($subject, \Smarty\Smarty::$_CHARSET, $current_charset);
        }
    }
    return $subject;
}