効率的な人民元金額換算プログラム PHP バージョン

//人民元金額を大文字に変換するプログラムのPHPバージョン
class Ext_Num2Cny{
 static $basical = array(0=>"zero","壹","谰", "三", "四","五","鲁","旒","八","九");
 static $advanced=array(1=>"十","百","千");

 public static function ParseNumber($number){
 $number=trim($number);
 if ($number>999999999999) return "数値が大きすぎて処理できません。";
 if ($ number==0) return "zero";
 if(strpos($number,'.')){
 $number=round($number,2);
 $data=explode(".",$number);
 $data[0 ]=self::int($data[0]);
 $data[1]=self::dec($data[1]);
 return $data[0].$data[1 ];
 }else {
 return self::int($number).'whole';
 }
 }

 public static function int($number){
 $arr=array_reverse(str_split($number));
 $data='' ;
 $zero=false;
 $zero_num=0;
 foreach ($arr as $k=>$v){
 $_chinese='';
 $zero=($v==0) )?true:false ;
 $x=$k%4;
 if($x && $zero && $zero_num>1) continue;
 switch ($x){
 case 0:
 if($zero){
 $zero_num=0;
 }else{
 $_chinese=self::$basical[$v];
 $zero_num=1;
 }
 if($k==8){
 $_chinese.='billion';
 }elseif($ k==4){
 $_chinese.='wan';
 }
 ブレーク;
 デフォルト:
 if($zero){
 if($zero_num==1){
 $_chinese=self ::$basical[ $v];
 $zero_num++;
 }
 }else{
 $_chinese=self::$basical[$v];
 $_chinese.=self::$advanced[$x];
 }
 }
 $data =$_chinese.$data;
 }
 return $data.'元';
 }

 public static function dec($number){
 if(strlen($number)<2) $number .='0' ;
 $arr=array_reverse(str_split($number));
 $data='';
 $zero_num=false;
 foreach ($arr as $k=>$v){
 $zero =($v= =0)?true:false;
 $_chinese='';
 if($k==0){
 if(!$zero){
 $_chinese=self::$basical[$v ];
 $_chinese .='fen';
 $zero_num=true;
 }
 }else{
 if($zero){
 if($zero_num){
 $_chinese=self::$basical[$v] ;
 }
 } else{
 $_chinese=self::$basical[$v];
 $_chinese.='angle';
 }
 }
 $data=$_chinese.$data;
 }
 return $data ;
 }
}

PHP