I have setup facebook authentication using php and it goes something like this first getting the authorization here :

https://graph.facebook.com/oauth/authorize?client_id=<?= $facebook_app_id ?>&redirect_uri=http://www.example.com/facebook/oauth/&scope=user_about_me,publish_stream

then getting the access Token here :

$url = "https://graph.facebook.com/oauth/access_token?client_id=".$facebook_app_id."&redirect_uri=http://www.example.com/facebook/oauth/&client_secret=".$facebook_secret."&code=".$code;"

function get_string_between($string, $start, $end){ 
    $string = " ".$string; 
    $ini = strpos($string,$start); 
    if ($ini == 0) return ""; 
    $ini += strlen($start); 
    $len = strpos($string,$end,$ini) - $ini; 
    return substr($string,$ini,$len); 
} 


$access_token = get_string_between(file_get_contents($url), "access_token=", "&expires=");     

then getting user info :

$facebook_user = file_get_contents('https://graph.facebook.com/me?access_token='.$access_token);

$facebook_id = json_decode($facebook_user)->id;
$first_name = json_decode($facebook_user)->first_name;
$last_name = json_decode($facebook_user)->last_name;

this is pretty ugly ( in my opinion ) but it works....how ever....the user is still not logged in...because i did not create or retrieve any session variables to confirm that the user is logged in to facebook...

which means that after getting the authentication done the use still has to login ....

first: is there a better way using php to do what i did above ? second: how do i set/ get session variable / cookies that ensure that the user doesnt have to click login

thanks for your help