<?php

/**
* @package utf8
*/

//---------------------------------------------------------------
/**
* UTF-8 aware alternative to str_ireplace
* Case-insensitive version of str_replace
* Note: requires utf8_strtolower
* Note: it's not fast and gets slower if $search / $replace is array
* Notes: it's based on the assumption that the lower and uppercase
* versions of a UTF-8 character will have the same length in bytes
* which is currently true given the hash table to strtolower
* @param string
* @return string
* @see http://www.php.net/str_ireplace
* @see utf8_strtolower
* @package utf8
*/
function utf8_ireplace($search, $replace, $str, $count = null)
{
    if (!is_array($search)) {
        $slen = strlen($search);
        if ($slen == 0) {
            return $str;
        }

        $lendif = strlen($replace) - strlen($search);
        $search = utf8_strtolower($search);

        $search  = preg_quote($search, '/');
        $lstr    = utf8_strtolower($str);
        $i       = 0;
        $matched = 0;
        while (preg_match('/(.*)' . $search . '/Us', $lstr, $matches)) {
            if ($i === $count) {
                break;
            }
            $mlen = strlen($matches[0]);
            $lstr = substr($lstr, $mlen);
            $str  = substr_replace($str, $replace, $matched + strlen($matches[1]), $slen);
            $matched += $mlen + $lendif;
            $i++;
        }
        return $str;
    } else {
        foreach (array_keys($search) as $k) {
            if (is_array($replace)) {
                if (array_key_exists($k, $replace)) {
                    $str = utf8_ireplace($search[$k], $replace[$k], $str, $count);
                } else {
                    $str = utf8_ireplace($search[$k], '', $str, $count);
                }
            } else {
                $str = utf8_ireplace($search[$k], $replace, $str, $count);
            }
        }
        return $str;
    }
}