PHPで小文字の金額を大文字に変換する

public static function num_case($num) {

$return = "";
$unit = array("分", "角度", "元", "全体");
$dw = array("", "十", "百", "千", "", "万", "十億", "千亿")
$char = array("zero", "一", "二", "三" 、"四"、"五"、"鲁"、"旒"、"八"、"玖");
preg_match_all("/(d*).?(d*)/", $num, $ar) ;

if($ar[2][0] != ""){
$return .= $ar[2][0][0] == 0 "" : $char[$ar[2] [ 0][0]] . $unit[1];
if(isset($ar[2][0][1])) $return .= $char[$ar[2][0][1] ] . $unit[0];
}else{
$return .= $unit[3] }


if ($ar[1][0] != "") {
$str = strrev( $ ar[1][0]);
$len = strlen($str);
$i = 0; $len; $i++ ) {
$out[$i] = $char[$str[$i]]
$out[$i] .= $str[$i] != "0"? : "";
if ($str[$i] + $str[$i-1] == 0)
$out[$i] = "";
if ($i%4 == 0)
$ out [$i] .= $dw[4+floor($i/4)]
}
$return = join("",array_reverse($out)) .
return $return;

}