PHP Decode

<?php @error_reporting(0); 
$ip    = $_SERVER['REMOTE_ADDR']; 
$detek = dirname(__FILE__).'/Save/' . $ip . '.txt'; 
if (file_exists($detek)) { 
    $Detect      = explode('|', file_get_contents(dirname(__FILE__).'/Save/' . $ip . '.txt')); 
    $negara      = $Detect[0]; 
    $nama_negara = $Detect[1]; 
    $kode_negara = $Detect[2]; 
} else { 
    $getip = 'http://extreme-ip-lookup.com/json/' . $ip; 
    $curl  = curl_init(); 
    curl_setopt($curl, CURLOPT_URL, $getip); 
    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true); 
    @curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true); 
    $content = curl_exec($curl); 
    curl_close($curl); 
    $details      = json_decode($content); 
    $country_code = $details->countryCode; 
    if ($country_code == 'GB') { 
        $negara = 'GB'; 
    } elseif ($country_code == 'C2' || $country_code == 'A1') { 
        $negara = 'US'; 
    } else { 
        $negara = $country_code; 
    } 
    if ($country_code == 'C2' || $country_code == 'A1') { 
        $nama_negara = 'United States'; 
    } else { 
        $nama_negara = $details-> country; 
    } 
    $kode_negara = strtolower($negara); 
    $open        = @fopen($detek, 'a'); 
    @fwrite($open, $negara . '|' . $nama_negara . '|' . $kode_negara); 
    @fclose($open); 
} 
$agent = $_SERVER['HTTP_USER_AGENT']; 
?>