<?php

$file = (isset($_GET['file'])) ? $_GET['file'] : '';

if (!empty($file) && file_exists($file)):
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename="'.basename($file).'"');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));
    flush(); // Flush system output buffer
    readfile($file);
else:
    http_response_code(404);
    echo 'Arquivo não encontrado ' . $file;
endif;