Returns the portion without breaking HTML

function html_substr($text, $max_str) {
    $qsingle = $qdouble = $pembuka = $penutup = $ambiltagawal = false;
    $n_text = strip_tags($text);
    $tagnya = $res = "";
    $alltag = array();
    $i = $n = 0;
    while ($n<$max_str AND $i<strlen($text) AND $n<strlen($n_text)) {
        $tanda  = $text[$i];
        $res .= $tanda;
        switch ($tanda) {
            case ' ':
                if (!$pembuka) { $n++; } else { $ambiltagawal = false; }
            break;
            case '<':
                $ambiltagawal = $pembuka = true;
            break;
            case '>':
                if ($pembuka) {
                    array_push($alltag, $tagnya);
                    $pembuka = $ambiltagawal = false;
                    $tagnya = "";
                } elseif ($penutup) {
                    array_pop($alltag);
                    $tagnya = "";
                    $penutup = false;
                }
            break;
            case '/':
                if ($pembuka AND !$qdouble AND !$qsingle) {
                    $pembuka = $ambiltagawal = false;
                    $penutup  = true;
                }
            break;
            case '"':
                $qdouble = ($qdouble)?false:true;
            break;
            case "'":
                $qsingle = ($qsingle)?false:true;
            break;
            default:
            if ($ambiltagawal OR $penutup) {
                $tagnya .= $tanda;
            } elseif (!$pembuka AND !$penutup) {
                $n++;
            }
        }
        $i++;
    }

    while ($alltag) {
        $res .= "</".array_pop($alltag).">";
    }
    return $res;
}