Authentication with PHP SDK - authentication

Question

I am having trouble using the PHP SDK for authentication. The effect I am trying to get is whene a user visits the site if they are loged in with FB they see "Logout" which loggs them out when clicked but if they are not logged in when they arrive they should see "You need to log in with FB" which loggs them in. The effect I am currently getting is that the site displays the "You need to log in with FB" even if the user is already logged in, whene this is clicked the user is taken to facebook.com with an error message displayed reading "An error occurred. Please try later". Im sure I must be missing something in my code but cant figure out what, I am fairly new to FB development. Please see my code below. Any help much appriciated.
<?php
require_once("facebook.php");
$user = $facebook->getUser();
$config = array();
$config[‘appId’] = xxx;
$config[‘secret’] = '{secret}';
$facebook = new Facebook($config);
$fbparams = array(
'scope' => 'read_stream, friends_likes',
'redirect_uri' => 'xxx'
);
session_start();
$loginUrl = $facebook->getLoginUrl($fbparams);
$params = array( 'next' => 'xxx' );
$logoutUrl = $facebook->getLogoutUrl($params);
if(!$user)
{
echo "<P>You need to log into FB</p>\n";
}
else
{
echo "<p style=\"margin-bottom:20px;\"><a href=\"{$logoutUrl} \">Logout</p>\n";
}
?>

Answer 1

Try this out
<?php
require_once("facebook.php");
$user = $facebook->getUser();
$config = array();
$config[‘appId’] = xxx;
$config[‘secret’] = '{secret}';
$facebook = new Facebook($config);
$fbparams = array(
'scope' => 'read_stream, friends_likes',
'redirect_uri' => 'xxx'
);
$loginUrl = $facebook->getLoginUrl($fbparams);
$params = array( 'next' => 'xxx' );
$logoutUrl = $facebook->getLogoutUrl($params);
<?php if ($user) { ?>
<p>Logout</p>
<?php } else { ?>
<p>Click here to View Your Stalker of the Day</p>
<?php } ?>

Answer 2

You can not call $facebook before creating the instance, This code should work:
<?php
session_start();
require_once("facebook.php");
$config = array();
$config[‘appId’] = xxx;
$config[‘secret’] = '{secret}';
$facebook = new Facebook($config);
$user = $facebook->getUser();
$fbparams = array(
'scope' => 'read_stream, friends_likes',
'redirect_uri' => 'xxx'
);
$loginUrl = $facebook->getLoginUrl($fbparams);
$params = array( 'next' => 'xxx' );
$logoutUrl = $facebook->getLogoutUrl($params);
if(!$user)
{
echo "<P>You need to log into FB</p>\n";
}
else
{
echo "<p style=\"margin-bottom:20px;\"><a href=\"{$logoutUrl} }\">Logout</p>\n";
}
?>

Answer 3

$params = array( 'next' => 'xxx' );
is deprecated SDK, use
$params = array( 'redirect_uri' => 'xxx' );
instead.