How not to bootstrap Magento

gistfile1.txt

// ...
// Regular index.php stuff above here

// default site
$mage_run_code = 'base';
$currentzone = 'UK';
$geo_country_code = 'GB';
if(isset($_SERVER['HTTP_X_STORE'])) {
    $currentzone = $_SERVER['HTTP_X_STORE'];
    $geo_country_code = $_SERVER['HTTP_X_STORE'];
}


if (isset($_SERVER['HTTP_CF_IPCOUNTRY'])) {
    $geo_country_code = $_SERVER['HTTP_CF_IPCOUNTRY'];
} elseif (isset($_SERVER['HTTP_X_FORWARDED_FOR'])) {
    $geo_country_code = @geoip_country_code_by_name($_SERVER['HTTP_X_FORWARDED_FOR']);
} else {
    $geo_country_code = apache_note("GEOIP_COUNTRY_CODE");
}
if (strlen($geo_country_code)==0 || $geo_country_code == '--') $geo_country_code = 'GB';


// bypass all this if in admin
if (!indexIsAdmin()) {

    if (isset($_COOKIE['frontend'])) {
        try {
            $session_id = $_COOKIE['frontend'];
            if (is_file('var/session/sess_'.$session_id)) {
                $session_data = file_get_contents('var/session/sess_'.$session_id);
                $szpattern = '#"shipping_zone";s:(?:[0-9]):"([A-Z]+)"#s';
                preg_match($szpattern, $session_data, $szmatches);
                if (is_array($szmatches) && isset($szmatches[1])) {
                    $session_shipping_zone = $szmatches[1];
                }
            }
        } catch (Exception $e) {

        }
    }

    // available sites, hard code for speed
    $websites = array(
        'UK'=>'base',
        'EU'=>'eur_website',
        'US'=>'usd_website',
        'ROW'=>'row_website',
    );

    // countries for each site, not listed go to base
    $uk_countries = array('GB', 'IM');
    $euro_countries = array('AD','AT','BE','BG','CY','CZ','DE','DK','EE','ES','FI','FR','GR','HR','HU','IE','IT','LT','LU','LV','MT','NL','PL','PT','RO','SE','SI','SK');
    $usd_countries = array('US','PR','UM');

    if (array_search($geo_country_code, $uk_countries)!==false) {
        $countryToRegion = 'UK';
    } elseif (array_search($geo_country_code, $euro_countries)!==false) {
        $countryToRegion = 'EU';
    } elseif (array_search($geo_country_code, $usd_countries)!==false) {
        $countryToRegion = 'US';
    } else {
        $countryToRegion = 'ROW';
    }
    // get current zone from url or session, else use geoip
    $changedZone = false;

    if (isset($_GET['shipto']) && isset($websites[$_GET['shipto']])) { // User wants to change the currency
        $currentzone = $_GET['shipto'];
        $mage_run_code = $websites[$currentzone];
        setcookie('changed_zone',$currentzone,strtotime( '+8 hours' ),'/');
    }
    elseif(isset($_COOKIE['changed_zone']))
    {
        $currentzone = $_COOKIE['changed_zone'];
        $mage_run_code = $websites[$currentzone];
    }
    else { // Max Mind

        if (isset($_COOKIE['maxmind'])) { // We already have a Max Mind request
            $currentzone = $_COOKIE['maxmind'];
        } else { // New Maxmind request and save cookie
            $ip = $_SERVER['REMOTE_ADDR'];
            $address = 'https://geoip.maxmind.com/geoip/v2.1/country/' . $ip;

            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $address);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
            curl_setopt($ch, CURLOPT_USERPWD, 'secret');

            $json = curl_exec($ch);
            curl_close($ch);

            $data = json_decode($json, true);
            if(is_array($data)) {
                if(isset($data['error'])) {
                    $country2letters = 'GB';
                } else {
                    $country2letters = strtoupper($data['registered_country']['iso_code']);
                }
            } else {
                $country2letters = 'GB';
            }

            $session_shipping_zone = $country2letters;
            $geo_country_code = $country2letters;

            $currentzone = '';
            if($currentzone == ''){
                // else use geoip
                if (array_search($geo_country_code, $uk_countries)!==false) {
                    $currentzone = 'UK';
                } elseif (array_search($geo_country_code, $euro_countries)!==false) {
                    $currentzone = 'EU';
                } elseif (array_search($geo_country_code, $usd_countries)!==false) {
                    $currentzone = 'US';
                } else {
                    $currentzone = 'ROW';
                }
            }
            setcookie('maxmind',$currentzone,strtotime( '+8 hours' ),'/');
        }
        $mage_run_code = $websites[$currentzone];
    }

}

Mage::run($mage_run_code, 'website');

if (!indexIsAdmin()) {
    Mage::getSingleton('core/session')->setShippingZone($currentzone);
    Mage::getSingleton('core/session')->setDetectedCountry($geo_country_code);
    Mage::getSingleton('core/session')->setChangedZone($session_user_changed_zone);

    if (!Mage::helper('customer')->isLoggedIn()) {
        if ($customer = Mage::getSingleton('customer/session')) {
            $customerId = $customer->getCustomerId();
            if (is_numeric($customerId) && $customerId>0) {
                Mage::getSingleton('customer/session')->unsetAll();
                Mage::getModel('persistent/session')->removePersistentCookie();
                Mage::helper('persistent/session')->setSession(null);
            }
        }
    }

    // save cart items to different session to preserve
    $cartitems = array();
    $cartHelper = Mage::helper('checkout/cart');
    $items = $cartHelper->getCart()->getItems();
    foreach ($items as $item) {
        $parent = $item->getParentItemId();
        if (is_null($parent)) {
            $_item = array();
            $_item['id'] = $item->getProductId();
            $_item['sku'] = $item->getSku();
            $_item['qty'] = $item->getQty();
            $cartitems[] = $_item;
        }
    }
    Mage::getSingleton('core/session')->setSavedCart(json_encode($cartitems));
}