get site base url

base_url.php

function base_url()
{
    $protocol = strtolower(substr($_SERVER["SERVER_PROTOCOL"], 0, 5)) == 'https' ? 'https://' : 'http://';
    $path = $_SERVER['PHP_SELF'];
    $path_parts = pathinfo($path);
    $directory = $path_parts['dirname'];
    $directory = ($directory == "/") ? "" : $directory;
    $host = $_SERVER['HTTP_HOST'];
    return $protocol . $host . $directory;
}