// 1. Get the original requested URI
$requestUri = $_SERVER['REQUEST_URI'];
$urlParts = parse_url($requestUri);
$path = isset($urlParts['path']) ? $urlParts['path'] : '';
$query = isset($urlParts['query']) ? '?' . $urlParts['query'] : '';

// 2. If uppercase exists, redirect to lowercase version
if (preg_match('/[A-Z]/', $path)) {
    $lowercasePath = strtolower($path);
    $destination = $lowercasePath . $query;
    header("Location: " . $destination, true, 301);
    exit();
}

// 3. If lowercase path exists, serve it normally
$fullPath = $_SERVER['DOCUMENT_ROOT'] . $path;

if (file_exists($fullPath) && !is_dir($fullPath)) {
    include($fullPath);
    exit();
}

// 4. If lowercase path does NOT exist → URL is dead → return 410 Gone
header("HTTP/1.1 410 Gone");
include($_SERVER['DOCUMENT_ROOT'] . '/404.htm');
exit();