Problem with facebook javascript sdk

I am trying to modify a wordpress theme to add FB login button. (I know it can be done using a plugin, but there are reasons that I want to do it only in the theme)

I am having problem with $session = $facebook->getSession(); This function $facebook->getSession() keeps returning NULL. This is what I have been doing.

1. I can successfully create facebook object. But I am not sure if I am able to successfully load
the facebook library. I am trying to initialize the library using this code (basically using hooks)

add_action( ‘wp_footer’, array( ‘WPfbConnect_Logic’, ‘fbconnect_init_scripts’), 1);
add_action(‘admin_footer’, array( ‘WPfbConnect_Logic’, ‘fbconnect_init_scripts’), 1);

function fbconnect_init_scripts(){
echo “in fbconnect_init_scripts”
<div id=”fb-root”></div>
<script>
{
alert(“test77”);
window.fbAsyncInit = function() {
alert(“test1”);
FB.init({
appId : ‘<?php echo $facebook->getAppId(); ?>’,
session : <?php echo json_encode($session); ?>, // don’t refetch the session when PHP already has it
status : true, // check login status
cookie : true, // enable cookies to allow the server to access the session
xfbml : true // parse XFBML
});
// whenever the user logs in, we refresh the page
FB.Event.subscribe(‘auth.login’, function() {
window.location.reload();
});
};
(function() {
var e = document.createElement(‘script’);
e.src = document.location.protocol + ‘//connect.facebook.net/en_US/all.js’;
e.async = true;
//alert(e.src)
document.getElementById(‘fb-root’).appendChild(e);
alert(“test2”)
}());

}
</script>
}
endif;

Any thoughts, what I am doing wrong. Will greatly appreciate your help. What is the best way to load facebook java script library? Where should this code be put?