How to get magento customer session values in root index file for switching store view

I have created 2 store views for my magento website running under magento 1.9.2, I need to use the same domain name for both of the websites. When a customer logged in, I need to change the store view to the second one. I need to check the customer session in the index.php file in root directory. But when I follow the below changes to index.php, I end up with an error

$store_id = 1;
//Check customer session here 
if(Mage::getSingleton('customer/session')->isLoggedIn()){ // Error occurs here
    $customer       = Mage::getModel('customer/session')->getCustomer();            
    $customerId     = $customer->getId(); 
    // $storeid  get logged in customer storeid may from customer custom attribute value added on admin edit form
    // $store_id value get changed here
}



Mage::app()->setCurrentStore($store_id);
umask(0);
$mageRunCode = isset($_SERVER['MAGE_RUN_CODE']) ? $_SERVER['MAGE_RUN_CODE'] : '';
$mageRunType = isset($_SERVER['MAGE_RUN_TYPE']) ? $_SERVER['MAGE_RUN_TYPE'] : 'store';

if($store_id == 2)
$mageRunCode = 'mysecondshop';

Mage::run($mageRunCode, $mageRunType);

When I check the issue, I find that we cannot use Mage::getSingleton before Mage::run, but for my current situation for switching between stores, I need to get logged in user details before mage run. Is there any way to achieve my requirement?

Solution

In magento it is not possible to check session data unless Mage::run is initilaized. We need to do some temporary storage like cookie to achieve this. Hopefully the below steps will make it works.

Create a custom module with observer for saving, clearing and checking cookie. Your config.xml file is given below

<!--------------------------------------------------------------------->
<customer_login>
  <observers>
    <Company_Modulename_model_customer_login>
      <class>Company_Modulename_Model_Observer</class>
      <method>afterCustomerLoggedIn</method>
    </Company_Modulename_model_customer_login>
  </observers>
</customer_login>
<customer_logout>
  <observers>
    <Company_Modulename_model_customer_logout>
      <class>Company_Modulename_Model_Observer</class>
      <method>afterCustomerLoggedOut</method>
    </Company_Modulename_model_customer_logout>
  </observers>
</customer_logout>
<controller_action_layout_load_before>
  <observers>
    <Company_Modulename_model_layoutload_observer>
      <class>Company_Modulename_Model_Observer</class>
      <method>beforeLoadLayout</method>
    </Company_Modulename_model_layoutload_observer>
  </observers>
</controller_action_layout_load_before>
<!--------------------------------------------------------------------->

Observer implementation is given below

public function afterCustomerLoggedIn(Varien_Event_Observer $observer)
{
    $customer = $observer->getCustomer();
    $cid      = $customer->getid();
    $webId    = $customer->getWebsiteId();
    Mage::getModel('core/cookie')->set('_storeuid',$cid, 60*60*24*1);  // Create cookie
    Mage::getModel('core/cookie')->set('_storeid',$webId, 60*60*24*1); // Create cookie

}


public function afterCustomerLoggedOut(Varien_Event_Observer $observer)
{
    $customer = $observer->getCustomer();
    $cid      = $customer->getid();
    $webId    = $customer->getWebsiteId();  
    Mage::getModel('core/cookie')->set('_storeuid','0', 1); // Clear cookie
    Mage::getModel('core/cookie')->set('_storeid','0', 1);  // Clear cookie

}

Before rendering pages

public function beforeLoadLayout(Varien_Event_Observer $observer)
{


    $cookieValue = Mage::getModel('core/cookie')->get('_storeuid');
    $baseurl = Mage::getBaseUrl();

    if(Mage::getSingleton('customer/session')->isLoggedIn()){ // For more security , if someone change the cookie value


        $customer = Mage::getModel('customer/session')->getCustomer();          
        $webId    = $customer->getWebsiteId();
        $cid      = $customer->getId();

        if( $cookieValue != $cid ){

                Mage::getModel('core/cookie')->set('_storeuid',$cid, 60*60*24*1);
                Mage::getModel('core/cookie')->set('_storeid',$webId, 60*60*24*1);
                header("Location: ".$baseurl); exit;

       }
    }else{

        if( (isset($cookieValue)) && ($cookieValue > 0)  ){ // Clear cookie if session is cleared

            Mage::getModel('core/cookie')->set('_storeuid','0', 1);
            Mage::getModel('core/cookie')->set('_storeid','0', 1);
            header("Location: ".$baseurl); exit;

        }

    }
}

And Finally in index.php , you can check the cookie for switching the store value for loggedin customers

$store_id = 1;
if( (isset($_COOKIE['_storeur'])) && ($_COOKIE['_storeur'] > 0)  ){
    $store_id = $_COOKIE['_storeur'];
}

$mageRunCode = isset($_SERVER['MAGE_RUN_CODE']) ? $_SERVER['MAGE_RUN_CODE'] : '';
$mageRunType = isset($_SERVER['MAGE_RUN_TYPE']) ? $_SERVER['MAGE_RUN_TYPE'] : 'store';

if($store_id == 2 ) $mageRunCode = 'store2';
if($store_id == 3 ) $mageRunCode = 'store3';
//....................
Mage::run($mageRunCode, $mageRunType);