The code snippet below is a demo in how to redirect users to sub sites based on their country IP location.
On this code I am using CloudFlare geo location API – the code is not perfect but could be a good starting point 🙂
 

// collect the current state from the URL and CloudFlare

$user_country_code = strtolower($_SERVER["HTTP_CF_IPCOUNTRY"]);
$site_subdomain = strtolower(array_shift(explode(".",$_SERVER['HTTP_HOST'])));

if ( $user_country_code == $site_subdomain ) {

  // this is already using the country-code mapped version
  // do nothing
  
  } else {

    switch($user_country_code) {  // check if it's a country we currently support

       case 'et';
       case 'us';
       case 'gb'; 
       
       // yes - redirect to the specific subdomain
       header( 'Location: http://'.$user_country_code.'.example.com');
       break;
       default;
       
       // no - redirect to www if not already there
       if ( 'www' == $site_subdomain ) {
         // already at www!
         // do nothing
       
       } else {
       
         // redirect to www
         header( 'Location: http://www.example.com');
         break;
       }
    } 
       
}

Thank you for seeing my code snippet and fell free to share and comment 🙂 . Do you have a code snippet and you want to see it publish on my site ? I will be more than happy to do it please send me a message, (here)