Makes it easy for your site to use Facebook Connect, Google Connect, in a wholly modular way. Based on Simple Facebook Connect (http://ottopress.com/wordpress-plugins/simple-facebook-connect/) by Otto

facebook-connect.php

<?php
/*
 * Base
 *
 */

// basic XFBML load into footer
function psc_fb_load_args() {
	/*
	global $sfc_comm_comments_form;
	if ($sfc_comm_comments_form != true)  { 
		return; // nothing to do, not showing comments
	}
	*/
	if( comments_open() && !is_user_logged_in() ) {
		$options = get_option('psc_options');
		$defaults = array(
			'appId' => $options['fb_appid'],
			'channelUrl' => home_url('fb-channel-file/'),
			'status' => true, 
			'cookie' => true, 
			'xfbml' => false,
			'oauth' => true,
		);
		
		$args = apply_filters( 'psc_fb_args', $defaults );
		$args = wp_parse_args($args, $defaults);
		?>

		var fbArgs = <?=json_encode($args);?>

		<?php
	}
};
add_action('psc_footer_script','psc_fb_load_args', 20); // 20, to put it at the end of the footer insertions. sub-plugins should use 30 for their code

function psc_channel_file() {
	global $wp;
	$options = get_option('psc_options');
    $wp->add_query_var('fb-channel-file');
    add_rewrite_rule('fb-channel-file' . '?$', 'index.php?fb-channel-file=1', 'top');
}
add_action('init','psc_channel_file');

function psc_fb_channel_file_catcher() {
	if ( get_query_var('fb-channel-file') == 1 ) {
		
		$cache_expire = 60*60*24*365;
		header("Pragma: public");
		header("Cache-Control: max-age=".$cache_expire);
		header('Expires: ' . gmdate('D, d M Y H:i:s', time() + $cache_expire) . ' GMT');
		echo '<script src="//connect.facebook.net/en_US/all.js"></script>';
		exit;
	}
}
add_action('template_redirect','psc_fb_channel_file_catcher');

// the cookie is signed using our application secret, so it's unfakable as long as you don't give away the secret
function psc_fb_cookie_parse() {
	$options = get_option('psc_options');
	
	$cookie = $_COOKIE['fbsr_' . $options['fb_appid']];
	$args = array();
	
	if ( !empty( $cookie ) ) {
		if ( list($encoded_sig, $payload ) = explode('.', $cookie, 2) ) {
			$sig = psc_base64_url_decode($encoded_sig); 
			if (hash_hmac('sha256', $payload, $options['fb_app_secret'], true) == $sig) {
				$args = json_decode(psc_base64_url_decode($payload), true);
			}
		}
	}
	
	return $args;
}

// this is not a hack or a dangerous function.. the base64 decode is required because Facebook is sending back base64 encoded data in the signed_request bits. 
// See http://developers.facebook.com/docs/authentication/signed_request/ for more info
function psc_base64_url_decode($input) {
    return base64_decode( strtr($input, '-_', '+/') );
}


function psc_fb_remote($obj, $connection='', $args=array(), $type = 'GET') {

	// save the access tokens for later use in the same request
	static $saved_access_tokens;
	
	if ( empty($args['access_token']) && isset($saved_access_tokens[$obj]) && $saved_access_tokens[$obj] = $obj ) {
		$args['access_token'] = $saved_access_tokens[$obj];
	}
	
	$options = get_option('psc_options');
	
	// get the access token
	if ( empty($args['access_token']) && !empty($args['code']) ) {
		$resp = wp_remote_get("https://graph.facebook.com/oauth/access_token?client_id={$options['fb_appid']}&redirect_uri=&client_secret={$options['fb_app_secret']}&code={$args['code']}");	
		if ( !is_wp_error($resp) && wp_remote_retrieve_response_code( $resp ) == 200 ) {
			$args['access_token'] = str_replace( 'access_token=', '', $resp['body'] );
			$saved_access_tokens[$obj] = $args['access_token'];
		} else {
			return false;
		}
	}
	
	$type = strtoupper($type);
	
	if ( empty($obj) ) {
		return null;
	}
		
	$url = 'https://graph.facebook.com/' . $obj;
	if ( !empty($connection) ) {
		 $url .= '/' . $connection;
	}
	if ($type == 'GET') {
		$url .= '?' . http_build_query($args);
	}
	
	$args['sslverify'] = 0;

	if ($type == 'POST') {
		$data = wp_remote_post($url, $args);
	} else if ($type == 'GET') {
		$data = wp_remote_get($url, $args);
	} 
	
	if ( $data && !is_wp_error($data) ) {
		$resp = json_decode($data['body'], true);
		return $resp;
	}
	
	return false;
}

// finds a item from an array in a string
if ( !function_exists('straipos') ) :
function straipos($haystack, $array, $offset=0) {
   $occ = array();
   for ($i = 0; $i<sizeof($array); $i++) {
       $pos = strpos($haystack, $array[$i], $offset);
       if ( is_bool($pos) ) continue;
       $occ[$pos] = $i;
   }
   
   if ( sizeof($occ) < 1 ) { return false; }
   ksort($occ);
   reset($occ);
   list($key, $value) = each($occ);
   return array($key, $value);
}
endif;



/*
 * Facebook Comments (sfc-comments.php)
 *
 */
function psc_fb_button() {
	?>
	<div id="facebook-connect" class="button">
		<p><a href="#"><span>Log In with </span>Facebook</a></p>
	</div>
	<?php
}
add_action('psc_add_button', 'psc_fb_button');

// generate facebook avatar code for FB user comments
function psc_fb_avatar($avatar, $id_or_email, $size = '96', $default = '', $alt = false) {
	
	// check to be sure this is for a comment
	if ( !is_object($id_or_email) || !isset($id_or_email->comment_ID) || $id_or_email->user_id) {
		 return $avatar;
	}

	// check for fbuid comment meta
	$fbuid = get_comment_meta($id_or_email->comment_ID, 'fbuid', true);
	if ($fbuid) {
		// return the avatar code
		return "<img width='{$size}' height='{$size}' class='avatar avatar-{$size} fbavatar' src='https://graph.facebook.com/{$fbuid}/picture?width={$size}&height={$size}' />";
	}

	return $avatar;
}
add_filter('get_avatar','psc_fb_avatar', 10, 5);

// Injects the data from Facebook into the $_POST object sent to the server.
function psc_fb_inject_comment_data($comment_post_ID) {
	if ( is_user_logged_in() ) {
		return; // do nothing to WP users
	}

	$uid = $_POST['psc_fb_user_id'];
	$token = $_POST['psc_fb_token'];

	if ( empty($uid) || empty($token) ) {
		return; // need both of these to get the data from FB
	}

	$url = "https://graph.facebook.com/{$uid}/?fields=name,email&access_token={$token}";
	$data = wp_remote_get( $url, array('sslverify' => 0) );
	
	if ( !is_wp_error($data) ) {
		$json = json_decode($data['body'], true);
		if ($json) {
			$json = apply_filters('psc_fb_user_data', $json, $uid);
			//$_POST['author'] = $json['name'];
			$_POST['url'] = "http://www.facebook.com/profile.php?id={$uid}"; //Even though we're not displaying the URL publically we can use this field to query how many commenters are logging in using Facebook.
			$_POST['email'] = $json['email'];
		}
	}
}
add_filter('pre_comment_on_post','psc_fb_inject_comment_data');

// store the FB user ID as comment meta data ('fbuid')
function psc_fb_store_metadata($comment_id) {
	$uid = $_POST['psc_fb_user_id'];
	$token = $_POST['psc_fb_token'];
	
	if ( !empty($uid) && !empty($token) ) {
		// validate token
		$url = "https://graph.facebook.com/{$uid}/?fields=name,email&access_token={$token}";
		$data = wp_remote_get( $url, array('sslverify'=>0) );

		if ( !is_wp_error($data) ) {
			$json = json_decode( $data['body'], true );
			if ( !empty( $json['name'] ) ) {		
				update_comment_meta($comment_id, 'fbuid', $uid);
			}
		}
	}
}
add_action('comment_post','psc_fb_store_metadata', 10, 1);

google-connect.php

<?php
/*
 * Base
 *
 */
function sgc_oauth_request_link($scope, $action='', $forceprompt=false) {
	$options = get_option('psc_options');
	
	$args['response_type'] = 'code';
	$args['client_id'] = $options['goog_appid'];
	$args['redirect_uri'] = home_url( $options['goog_oauthcallback'] );
	$args['scope'] = $scope;
	
	if ($forceprompt) {
		$args['approval_prompt'] = 'force';
		$args['access_type'] = 'offline';
	} else {
		$args['approval_prompt'] = 'auto';
		$args['access_type'] = 'online';
	}
	
	if ( !empty($action) ) {
		$args['state'] = $action;
	}
	
	$auth = 'https://accounts.google.com/o/oauth2/auth?' . http_build_query($args);
	
	return $auth;
}

function sgc_get_userinfo($token) {
	$headers['Authorization'] = 'Bearer '.$token;
	$request['headers'] = $headers;
	$request['sslverify'] = false;
	
	$data = wp_remote_get('https://www.googleapis.com/oauth2/v1/userinfo', $request);
	
	if ( is_wp_error( $data ) || 200 != wp_remote_retrieve_response_code( $data ) )
		return false;
	
	$resp = json_decode( wp_remote_retrieve_body( $data ), true );
	
	return $resp;
}

function psc_goog_add_rewrite() {
       global $wp;
       $options = get_option('psc_options');
       $wp->add_query_var($options['goog_oauthcallback']);
       add_rewrite_rule($options['goog_oauthcallback'] . '?$', 'index.php?oauth2callback=1', 'top');
}
add_action('init','psc_goog_add_rewrite');

function psc_goog_oauth_catcher() {
	if ( get_query_var('oauth2callback') == 1 ) {
	
		$oauth = array();
		if ( !empty( $_REQUEST['code'] ) ) {
			$oauth['code'] = $_REQUEST['code'];
			$oauth['token'] = psc_get_goog_token( $oauth['code'] );
		}
		else if ( !empty($_REQUEST['error']) ) {
			$oauth['error'] = $_REQUEST['error'];
		}
		
		if ( !empty( $_REQUEST['state'] ) )
			do_action('psc_goog_state_' . $_REQUEST['state'], $oauth );
		
		// if we made it here, then the action didn't do anything so redirect to the home page
		wp_redirect( home_url() );
	}
}
add_action('template_redirect','psc_goog_oauth_catcher');

function psc_get_goog_token($code, $refresh=false) {
	$options = get_option('psc_options');
	
	if ($refresh) {
		$req['refresh_token'] = $code;
	} else {
		$req['code'] = $code;
	}
	
	$req['client_id'] = $options['goog_appid'];
	$req['client_secret'] = $options['goog_app_secret'];
	
	if (!$refresh) {
		$req['redirect_uri'] = home_url( $options['goog_oauthcallback'] );
	}
	if ($refresh) {
		$req['grant_type'] = 'refresh_token';
	} else {
		$req['grant_type'] = 'authorization_code';
	}
	
	$args['sslverify'] = false;
	$args['body'] = $req;
	
	$data = wp_remote_post('https://accounts.google.com/o/oauth2/token', $args);

	if ( is_wp_error( $data ) || wp_remote_retrieve_response_code( $data ) != 200 ) {
		return false;
	}
	
	$resp = json_decode( wp_remote_retrieve_body( $data ), true );

	return $resp;
}


function psc_get_goog_userinfo($token) {
	$headers['Authorization'] = 'Bearer '.$token;
	$request['headers'] = $headers;
	$request['sslverify'] = false;
	
	$data = wp_remote_get('https://www.googleapis.com/oauth2/v1/userinfo', $request);

	if ( is_wp_error( $data ) || 200 != wp_remote_retrieve_response_code( $data ) )
		return false;
	
	$resp = json_decode( wp_remote_retrieve_body( $data ), true );

	return $resp;
}

/*
 * Google Comments (sgc-comments.php)
 *
 */
function psc_goog_button() {
?>
	<div id="google-connect" class="button">
		<p><a href="#"><span>Sign In with </span>Google</a></p>
	</div>

<?php
}
add_action('psc_add_button', 'psc_goog_button');

function psc_goog_load_args() {
	if( comments_open() && !is_user_logged_in() ) {
		$options = get_option('psc_options');
		$defaults = array(
			'callback' => 'googSignInCallback',
			'clientid' => $options['goog_appid'],
			'cookiepolicy' => 'single_host_origin',
			'requestvisibleactions' => 'http://schemas.google.com/AddActivity',
			'scope' => 'https://www.googleapis.com/auth/userinfo.email https://www.googleapis.com/auth/plus.login'
		);
		
		$args = apply_filters( 'psc_goog_args', $defaults );
		$args = wp_parse_args($args, $defaults);
		?>
		
		var googArgs = <?=json_encode($args);?>
		
		<?php
	}
};
add_action('psc_footer_script','psc_goog_load_args', 20); // 20, to put it at the end of the footer insertions. sub-plugins should use 30 for their code

// Add user fields for Google based commenters
function psc_goog_inject_comment_data($comment_post_ID) {
	if ( is_user_logged_in() )  {
		return; // do nothing to WP users
	}

	if ( empty( $_POST['psc_goog_token'] ) ) {
		return;
	}
	
	$token = $_POST['psc_goog_token'];
	
	global $goog_user;
	if ( empty($goog_user) ) {
		$goog_user = psc_get_goog_userinfo($token);
	}
	
	if ( !$goog_user ) {
		return;
	}

	$goog_user = apply_filters('psc_goog_user_data', $goog_user);
	//$_POST['author'] = $goog_user['name'];
	$_POST['url'] = 'https://plus.google.com/' . $goog_user['id'] . '/';
	$_POST['email'] = $goog_user['email'];
}
add_filter('pre_comment_on_post','psc_goog_inject_comment_data');



// store the user ID and picture as comment meta data
function psc_goog_store_metadata($comment_id) {
	global $goog_user;
	if ( empty($goog_user) || !isset($goog_user['id']) ) {
		return;
	}

	update_comment_meta($comment_id, 'googleid', $goog_user['id']);
	update_comment_meta($comment_id, 'googlepicture', 'https://plus.google.com/s2/photos/profile/' . $goog_user['id']);
}
add_action('comment_post','psc_goog_store_metadata', 10, 1);


// generate avatar code for Google user comments
function psc_goog_avatar($avatar, $id_or_email, $size = '96', $default = '', $alt = false) {
	
	// check to be sure this is for a comment
	if ( !is_object($id_or_email) || !isset($id_or_email->comment_ID) || $id_or_email->user_id) {
		return $avatar;
	}
		 
	// check for google picture comment meta
	$gp = get_comment_meta($id_or_email->comment_ID, 'googlepicture', true);
	if ($gp) {
		// return the avatar code
		$avatar = "<img class='avatar avatar-{$size} google-avatar' src='{$gp}?sz={$size}' width='{$size}' height='{$size}' />";
	}

	return $avatar;
}
add_filter('get_avatar','psc_goog_avatar', 10, 5);

pew-social-connect.php

<?php
/*
Plugin Name: Pew Social Connect
Description: Makes it easy for your site to use Facebook Connect, Google Connect, in a wholly modular way. Based on Simple Facebook Connect (http://ottopress.com/wordpress-plugins/simple-facebook-connect/) by Otto
Author: Russell Heimlich
Version: 0.1
Author URI: http://www.russellheimlich.com
License: GPL2
*/

// psc_ = Pew Social Connect

include 'facebook-connect.php';
include 'google-connect.php';

// Add the single sign-on container and load the button HTML.
function pew_social_connect() {
	?>
	<div id="single-sign-on" class="hide">
		<?php do_action('psc_add_button', ''); ?>
	</div>
	<p class="or hide"><span>Or</span></p>
	<?php
}

function pew_social_connect_footer() {
	global $post; 
	if(	is_single() && $post->comment_status === 'open' ):
?>
	<script type="text/javascript">
		var fbArgs, googArgs;
		<?php do_action('psc_footer_script'); ?>
	</script>
<?php
endif;
}
add_action('wp_footer','pew_social_connect_footer', 1);

// add the admin settings and such
function psc_admin_init() {
	$options = get_option('psc_options');
	if (empty($options['fb_app_secret']) || empty($options['fb_appid'])) {
		add_action('admin_notices', create_function( '', "echo '<div class=\"error\"><p>" . sprintf('Facebook Connect needs configuration information on its <a href="%s">settings</a> page.', admin_url('options-general.php?page=pew-socialconnect')) . "</p></div>';" ) );
	}
	if (empty($options['goog_app_secret']) || empty($options['goog_appid'])) {
		add_action('admin_notices', create_function( '', "echo '<div class=\"error\"><p>".sprintf('Google Connect needs configuration information on its <a href="%s">settings</a> page.', admin_url('options-general.php?page=pew-socialconnect'))."</p></div>';" ) );
	}

	wp_enqueue_script('jquery');
	register_setting( 'psc_options', 'psc_options', 'psc_options_validate' );
	
	add_settings_section('psc_fb', 'Facebook', 'psc_fb_section_text', 'psc_fb_section');
	if (!defined('PSC_FB_APP_ID')) { 
		add_settings_field('psc_fb_appid', 'Facebook Application ID', 'psc_setting_fb_appid', 'psc_fb_section', 'psc_fb');
	}
	if (!defined('PSC_FB_APP_SECRET')) {
		add_settings_field('psc_fb_app_secret', 'Facebook Application Secret', 'psc_setting_fb_app_secret', 'psc_fb_section', 'psc_fb');
	}
	
	add_settings_section('psc_goog', 'Google Plus', 'psc_goog_section_text', 'psc_goog_section');
	if (!defined('PSC_GOOG_APP_ID')) {
		add_settings_field('psc_goog_appid', 'Google Client ID', 'psc_setting_goog_appid', 'psc_goog_section', 'psc_goog');
	}
	if (!defined('PSC_GOOG_APP_SECRET')) { 
		add_settings_field('psc_goog_app_secret', 'Google Client Secret', 'psc_setting_goog_app_secret', 'psc_goog_section', 'psc_goog');
	}
	add_settings_field('psc_goog_oauth2callback', 'Google OAuth2 Callback', 'psc_setting_goog_oauthcallback', 'psc_goog_section', 'psc_goog');
}
add_action('admin_init', 'psc_admin_init', 9); // 9 to force it first, subplugins should use default

// add the admin options page
function psc_admin_add_page() {
	global $psc_options_page;
	$psc_options_page = add_options_page( 'Pew Social Connect', 'Pew Social Connect', 'manage_options', 'pew-socialconnect', 'psc_options_page');
}
add_action('admin_menu', 'psc_admin_add_page');

// display the admin options page
function psc_options_page() {
?>
	<div class="wrap">
		<?php screen_icon(); ?>
		<h2>Pew Social Connect</h2>
		<form method="post" action="options.php">
			<?php settings_fields('psc_options'); ?>
			<?php do_settings_sections('psc_fb_section'); ?>
			<?php do_settings_sections('psc_goog_section'); ?>
			<?php submit_button(); ?>
		</form>
	</div>
<?php
}

// Individual Settings Fields.
function psc_setting_fb_appid() {
	if (defined('PSC_FB_APP_ID')) return;
	$options = get_option('psc_options');
	echo "<input type='text' id='psc-fb-appid' name='psc_options[fb_appid]' value='{$options['fb_appid']}' size='40' /> ";
}

function psc_setting_fb_app_secret() {
	if (defined('PSC_FB_APP_SECRET')) return;
	$options = get_option('psc_options');
	echo "<input type='text' id='psc-fb-appsecret' name='psc_options[fb_app_secret]' value='{$options['fb_app_secret']}' size='40' /> ";
}

function psc_setting_goog_appid() {
	if (defined('PSC_GOOG_APP_ID')) return;
	$options = get_option('psc_options');
	echo "<input type='text' id='psc-goog-appid' name='psc_options[goog_appid]' value='{$options['goog_appid']}' size='100' /> ";
}

function psc_setting_goog_app_secret() {
	if (defined('PSC_GOOG_APP_SECRET')) return;
	$options = get_option('psc_options');
	echo "<input type='text' id='psc-goog-appsecret' name='psc_options[goog_app_secret]' value='{$options['goog_app_secret']}' size='40' /> ";
}

function psc_setting_goog_oauthcallback() {
	$options = get_option('psc_options');
	if ( empty( $options['goog_oauthcallback'] ) ) $options['goog_oauthcallback'] = "oauth2callback";
	echo home_url('/')." <input type='text' id='psc-goog-oauthcallback' name='psc_options[goog_oauthcallback]' value='{$options['goog_oauthcallback']}' size='30' /><br />";
	echo "You can use this field to change the callback endpoint. If you don't know what that means, leave it set to 'oauth2callback'. <br /> (Note: Setting this value incorrectly will break the plugin.)";
}



//Section Text
function psc_fb_section_text() {
	$options = get_option('psc_options');
	if (empty($options['fb_app_secret']) || empty($options['fb_appid'])) {
?>
	<p>To connect your site to Facebook, you will need a Facebook Application. If you have already created one, please insert your Application Secret and Application ID below.</p>
	<p><strong>Can't find your key?</strong></p>
	<ol>
		<li>Get a list of your applications from here: <a target="_blank" href="https://developers.facebook.com/apps">Facebook Application List</a></li>
		<li>Select the application you want, then copy and paste the Application Secret and Application ID from there.</li>
	</ol>

	<p><strong>Haven't created an application yet?</strong> Don't worry, it's easy!</p>
	<ol>
		<li>Go to this link to create your application: <a target="_blank" href="https://developers.facebook.com/apps">Facebook Application Setup</a></li>
		<li>After creating the application, put <strong><?= home_url('/'); ?></strong> in as the Site URL in the Website section.</li>
		<li>You can get the API information from the application on the
		<a target="_blank" href="https://developers.facebook.com/apps">Facebook Application List</a> page.</li>
		<li>Select the application you created, then copy and paste the Application Secret and Application ID from there.</li>
	</ol>
<?php
	}
}

function psc_goog_section_text() {
	$options = get_option('psc_options');
	if (empty($options['goog_app_secret']) || empty($options['goog_appid'])) {
?>
	<h3>Connecting to Google</h3>
	<p>To connect your site to Google, you will first need to create a Google Application.
		If you have already created one, please insert your Client ID and Client Secret below.</p>
		<h3>Quick Link</h3>
		<p><a target='_blank' href='https://code.google.com/apis/console/'>Google API Console</a></p>
		
		<h3>Detailed Setup Instructions</h3>
		<ol>
			<li>First, visit the Google API Console: <a target='_blank' href='https://code.google.com/apis/console/'>Google API Console</a>.</li>
			<li>Here, you will need to create a new project. Name the project using the name of your website, to make it easy to find later.</li>
			<li>In the Services section, you will need to turn on the 'Google+ API' to enable the plugin to get information from Google+.</li>
			<li>On the 'API Access' Tab, click the 'Create an OAuth 2.0 client ID' button.</li>
			<li>The 'Product name' will be the name of your website. You can also upload a logo if you wish (you can do this later if you want).</li>
			<li>The 'Application type' should be 'Web Application' and put in the address of your application. <br />
			Also don't forget to select http or https correctly for the address of your website, if you choose incorrectly it will not work.</li>
			<li>Note that you must put in your website's URL <strong>exactly</strong>. If your website doesn't actually have a www in it, then <em>don't put one in there</em>.</li>
			<li>For reference, your website's url is <strong><?=home_url('/');?></strong> and this must be <em>exactly</em> what you enter into this screen.</li>
			<li>The Redirect URI will thus be <strong><?=home_url('/' . $options['goog_oauthcallback']);?></strong>. If you see anything else, then you've entered your URL wrong.</li>
			<li>Finally, after you click the 'Create ID' button, you will find the Client ID and Client Secret fields. Copy and paste those onto this configuration screen.</li>
		</ol>
<?php
	}
}

// this will override all the main options if they are pre-defined
function psc_override_options($options) {
	if ( defined('PSC_FB_APP_SECRET') ) {
		$options['fb_app_secret'] = PSC_FB_APP_SECRET;
	}
	
	if ( defined('PSC_FB_APP_ID') ) {
		$options['fb_app_secret'] = PSC_FB_APP_SECRET;
	}
	
	if (defined('PSC_GOOG_APP_SECRET')) {
		$options['goog_app_secret'] = PSC_GOOG_APP_SECRET;
	}
	
	if (defined('PSC_GOOG_APP_ID')) {
		$options['goog_app_secret'] = PSC_GOOG_APP_SECRET;
	}
	
	return $options;
}
add_filter('option_psc_options', 'psc_override_options');





// validate our options
function psc_options_validate($input) {
	if (!defined('PSC_FB_APP_SECRET')) {
		// secrets are 32 bytes long and made of hex values
		$input['fb_app_secret'] = trim($input['fb_app_secret']);
		if ( !preg_match('/^[a-f0-9]{32}$/i', $input['fb_app_secret']) ) {
			$input['fb_app_secret'] = '';
		}
	}

	if (!defined('PSC_FB_APP_ID')) {
		// app ids are big integers
		$input['fb_appid'] = trim($input['fb_appid']);
		if ( !preg_match('/^[0-9]+$/i', $input['fb_appid']) ) {
			$input['fb_appid'] = '';
		}
	}
	
	if ( empty( $input['goog_oauthcallback'] ) ) {
		$input['goog_oauthcallback'] = "oauth2callback";
	}
	
	$input = apply_filters('psc_options_validate', $input); // filter to let sub-plugins validate their options too
	// flush the rules to make sure the callback sticks
	flush_rewrite_rules(false);
	return $input;
}