PHP 获取url参数

/**
 * 获取url参数
 *
 * @param unknown $action            
 * @param string $param            
 */
function __URL($url, $param = '')
{
    $url = \str_replace('SHOP_MAIN', '', $url);
    $url = \str_replace('APP_MAIN', 'wap', $url);
    $url = \str_replace('ADMIN_MAIN', ADMIN_MODULE, $url);
    // 处理后台页面
    $url = \str_replace(__URL__ . '/wap', 'wap', $url);
    $url = \str_replace(__URL__ . ADMIN_MODULE, ADMIN_MODULE, $url);
    $url = \str_replace(__URL__, '', $url);
    if (empty($url)) {
        return __URL__;
    } else {
        $str = substr($url, 0, 1);
        if ($str === '/' || $str === "\\") {
            $url = substr($url, 1, strlen($url));
        }
        if (REWRITE_MODEL) {
            
            $url = urlRouteConfig($url, $param);
            return $url;
        }
        $action_array = explode('?', $url);
        // 检测是否是pathinfo模式
        $url_model = url_model();
        if ($url_model) {
            $base_url = __URL__ . '/' . $action_array[0];
            $tag = '?';
        } else {
            $base_url = __URL__ . '?s=/' . $action_array[0];
            $tag = '&';
        }
        if (! empty($action_array[1])) {
            // 有参数
            return $base_url . $tag . $action_array[1];
        } else {
            if (! empty($param)) {
                return $base_url . $tag . $param;
            } else {
                return $base_url;
            }
        }
    }
}