redirect_to not followed.

in your code /inc/frontend/login_check.php

if(isset($encoded_url) && $encoded_url !=''){
	$callback =$callBackUrl.'apsl_login_id'.'=google_check';
}else{
	$callback =$callBackUrl.'apsl_login_id'.'=google_check';
}

vs twitter or facebook

if(isset($encoded_url) && $encoded_url !=''){
	$callback =$callBackUrl.'apsl_login_id'.'=facebook_check&redirect_to='.$encoded_url;
}else{
	$callback =$callBackUrl.'apsl_login_id'.'=facebook_check';
}

Ah! you can’t do redirect for Google to the normal way because Redirect URI has to be fixed/predefined.

instead the state param has be used

you will need to do similar to login_check.php for shortcodes the key is the "&state=".base64_encode("redirect_to=$encoded_url"); }

which Google will accept.

inc/frontend/login_integration.php:

<?php defined('ABSPATH') or die("No script kiddies please!"); ?>
<?php $options = get_option( APSL_SETTINGS ); 

$redirect_to = isset($_REQUEST['redirect_to']) ? $_REQUEST['redirect_to'] : '';

$encoded_url = urlencode($redirect_to);

?>
<div class='apsl-login-networks theme-<?php echo $options['apsl_icon_theme']; ?> clearfix'>
        <span class='apsl-login-new-text'><?php echo $options['apsl_title_text_field']; ?></span>
        <?php if( isset($_REQUEST['error']) || isset($_REQUEST['denied']) ){ ?>
        <div class='apsl-error'>
                <?php _e('You have Access Denied. Please authorize the app to login.', APSL_TEXT_DOMAIN ); ?>
        </div>
        <?php } ?>

        <div class='social-networks'>
        <?php foreach($options['network_ordering'] as $key=>$value): ?>
        <?php   if($options["apsl_{$value}_settings"]["apsl_{$value}_enable"]==='enable'){ ?>
         <a href="?apsl_login_id=<?php echo $value; ?>_login<?php if ($encoded_url) { echo "&state=".base64_encode("redirect_to=$encoded_url"); } ?>" title='<?php _e('Login with', APSL_TEXT_DOMAIN ); echo ' '.$value; ?>' >
         <div class="apsl-icon-block icon-<?php echo $value; ?> clearfix">
                <i class="fa fa-<?php echo $value; ?>"></i>
                <span class="apsl-login-text"><?php _e('Login', APSL_TEXT_DOMAIN ); ?></span>
                <span class="apsl-long-login-text"><?php _e('Login with', APSL_TEXT_DOMAIN ); ?><?php echo ' '.$value; ?></span>
         </div>
         </a>
                <?php } ?>
        <?php endforeach; ?>
        </div>
</div>

/inc/frontend/login_check.php

<?php defined( 'ABSPATH' ) or die( "No script kiddies please!" ); ?>
<?php
if( !class_exists( 'APSL_Lite_Login_Check_Class' ) ){
    class APSL_Lite_Login_Check_Class{

        //constructor
        function __construct(){
                if ( isset($_GET['apsl_login_id'])){
                        if (isset( $_REQUEST['state'] )) {
                             parse_str(base64_decode($_REQUEST['state']), $state_vars);

                             if ( isset($state_vars['redirect_to']) ) {
                                 $_GET['redirect_to'] = $_REQUEST['redirect_to'] = $state_vars['redirect_to'];
                             }
                        }

                $exploder=explode( '_', $_GET['apsl_login_id'] );
                switch($exploder[0]){
                    case 'facebook':
                        //include( APSL_PLUGIN_DIR.'facebook/src/facebook.php' );
                        if (version_compare(PHP_VERSION, '5.4.0', '<')) {
                           echo _e('The Facebook SDK requires PHP version 5.4 or higher. Please notify about this error to site admin.', APSL_TEXT_DOMAIN );
                            die();
                        }
                        $this->onFacebookLogin();
                        break;

                    case 'twitter':
                        if( !class_exists( 'TwitterOAuth' ) ){
                        include( APSL_PLUGIN_DIR.'twitter/OAuth.php' );
                        include( APSL_PLUGIN_DIR.'twitter/twitteroauth.php' );
                        }
                        $this->onTwitterLogin();
                        break;

                    case 'google':
                        include( APSL_PLUGIN_DIR.'google/Client.php' );
                        include( APSL_PLUGIN_DIR.'google/Service/Plus.php' );
                        $this->onGoogleLogin();
                        break;
                }
            }
        }

        //for facebook login
        function onFacebookLogin(){
            $response = new stdClass();
            $result = $this->facebookLogin($response);
            if(isset($result->status) == 'SUCCESS'){
                $row = $this->getUserByMail( $result->email );
                $options = get_option( APSL_SETTINGS );

                if(!$row){
                    $this->creatUser($result->username, $result->email);
                    $row = $this->getUserByMail( $result->email);
                    update_user_meta($row->ID, 'email', $result->email);
                    update_user_meta($row->ID, 'first_name', $result->first_name);
                    update_user_meta($row->ID, 'last_name', $result->last_name);
                    update_user_meta($row->ID, 'deuid', $result->deuid);
                    update_user_meta($row->ID, 'deutype', $result->deutype);
                    update_user_meta($row->ID, 'deuimage', $result->deuimage);
                    update_user_meta($row->ID, 'description', $result->about);
                    update_user_meta($row->ID, 'sex', $result->gender);
                    wp_update_user( array ('ID' => $row->ID, 'display_name' => $result->first_name.' '.$result->last_name, 'role'=>$options['apsl_user_role'], 'user_url' => $result->url) ) ;
                }
                $this->loginUser($row->ID);
            }
        }

        function facebookLogin(){
                $request 	= $_REQUEST;
                $site 		= $this->siteUrl();
                $callBackUrl= $this->callBackUrl();
                $response 	= new stdClass();
                $return_user_details = new stdClass();
                $exploder=explode('_', $_GET['apsl_login_id']);
                $action		= $exploder[1];
                $options = get_option( APSL_SETTINGS );
                $config = array(
                                  'app_id' 					=> $options['apsl_facebook_settings']['apsl_facebook_app_id'],
                                  'app_secret' 				=> $options['apsl_facebook_settings']['apsl_facebook_app_secret'],
                                  'default_graph_version' 	=> 'v2.4'
                              );

                include( APSL_PLUGIN_DIR.'facebook/autoload.php' );
                $fb = new Facebook\Facebook($config);

                $encoded_url = isset($_GET['redirect_to']) ? $_GET['redirect_to'] : '';
                if(isset($encoded_url) && $encoded_url !=''){
                    $callback =$callBackUrl.'apsl_login_id'.'=facebook_check&redirect_to='.$encoded_url;
                }else{
                    $callback =$callBackUrl.'apsl_login_id'.'=facebook_check';
                }

                if ($action == 'login'){
                        // Well looks like we are a fresh dude, login to Facebook!
                        $helper = $fb->getRedirectLoginHelper();
                        $permissions = array('email', 'public_profile'); // optional
                        $loginUrl = $helper->getLoginUrl($callback, $permissions);
                        $this->redirect($loginUrl);
                }else{
                        if(isset($_REQUEST['error'])){
                        $response->status 		= 'ERROR';
                        $response->error_code 	= 2;
                        $response->error_message= 'INVALID AUTHORIZATION';
                        return $response;
                        die();
                        }
                        if (isset($_REQUEST['code'])) {
                                $helper = $fb->getRedirectLoginHelper();
                                try {
                                    $accessToken = $helper->getAccessToken();
                                } catch(Facebook\Exceptions\FacebookResponseException $e) {

                                      // When Graph returns an error
                                      echo 'Graph returned an error: ' . $e->getMessage();
                                      exit;
                                } catch(Facebook\Exceptions\FacebookSDKException $e) {

                                      // When validation fails or other local issues
                                      echo 'Facebook SDK returned an error: ' . $e->getMessage();
                                    exit;
                                }

                                if (isset($accessToken)) {
                                    // Logged in!
                                    $_SESSION['facebook_access_token'] = (string) $accessToken;
                                    $fb->setDefaultAccessToken($accessToken);

                                    try {
                                      $response = $fb->get('/me?fields=email,name, first_name, last_name, gender, link, about, address, bio, birthday, education, hometown, is_verified, languages, location, website');
                                      $userNode = $response->getGraphUser();
                                    } catch(Facebook\Exceptions\FacebookResponseException $e) {
                                      // When Graph returns an error
                                      echo 'Graph returned an error: ' . $e->getMessage();
                                      exit;
                                    } catch(Facebook\Exceptions\FacebookSDKException $e) {
                                      // When validation fails or other local issues
                                      echo 'Facebook SDK returned an error: ' . $e->getMessage();
                                      exit;
                                    }

                                    $user_profile = $this->accessProtected($userNode, 'items');
                                    if($user_profile!=null){
                                        $return_user_details->status 		= 'SUCCESS';
                                        $return_user_details->deuid		= $user_profile['id'];
                                        $return_user_details->deutype		= 'facebook';
                                        $return_user_details->first_name	= $user_profile['first_name'];
                                        $return_user_details->last_name	= $user_profile['last_name'];
                                        $return_user_details->email		= $user_profile['email'];
                                        $return_user_details->username		= $user_profile['email'];
                                        $return_user_details->gender 		= $user_profile['gender'];
                                        $return_user_details->url 			= $user_profile['link'];
                                        $return_user_details->about 		= ''; //facebook doesn't return user about details.
                                        $headers = get_headers('https://graph.facebook.com/'.$user_profile['id'].'/picture',1);

                                        // just a precaution, check whether the header isset...
                                        if(isset($headers['Location'])) {
                                            $return_user_details->deuimage = $headers['Location']; // string
                                        } else {
                                            $return_user_details->deuimage = false; // nothing there? .. weird, but okay!
                                        }
                                        $return_user_details->error_message = '';
                                        }else{
                                            $return_user_details->status 		= 'ERROR';
                                            $return_user_details->error_code 	= 2;
                                            $return_user_details->error_message= 'INVALID AUTHORIZATION';
                                        }
                                }
                        } else {
                            // Well looks like we are a fresh dude, login to Facebook!
                            $helper = $fb->getRedirectLoginHelper();
                            $permissions = array('email', 'public_profile'); // optional
                            $loginUrl = $helper->getLoginUrl($callback, $permissions);
                            $this->redirect($loginUrl);
                        }

                }
                return $return_user_details;
        }

        //for twitter login
        function onTwitterLogin(){
            $result = $this->twitterLogin();
            if(isset($result->status) == 'SUCCESS'){
                $row = $this->getUserByMail( $result->email);
                $options = get_option( APSL_SETTINGS );
                if(!$row){
                    $this->creatUser($result->username, $result->email);
                    $row = $this->getUserByMail( $result->email);
                    update_user_meta($row->ID, 'email', $result->email);
                    update_user_meta($row->ID, 'first_name', $result->first_name);
                    update_user_meta($row->ID, 'last_name', $result->last_name);
                    update_user_meta($row->ID, 'deuid', $result->deuid);
                    update_user_meta($row->ID, 'deutype', $result->deutype);
                    update_user_meta($row->ID, 'deuimage', $result->deuimage);
                    update_user_meta($row->ID, 'description', $result->about);
                    wp_update_user( array ('ID' => $row->ID, 'display_name' => $result->first_name.' '.$result->last_name, 'role'=>$options['apsl_user_role'], 'user_url' => $result->url) ) ;
                }
                $this->loginUser($row->ID);
            }
        }

        function twitterLogin(){
            $request 	= $_REQUEST;
            $site 		= $this->siteUrl();
            $callBackUrl= $this->callBackUrl();
            $response 	= new stdClass();
            $exploder=explode('_', $_GET['apsl_login_id']);
            $action		= $exploder[1];
            @session_start();
            $options = get_option( APSL_SETTINGS );
            if ($action == 'login'){
                // Get identity from user and redirect browser to OpenID Server
                if(!isset($request['oauth_token']) || $request['oauth_token']==''){
                    $twitterObj 	= new TwitterOAuth($options['apsl_twitter_settings']['apsl_twitter_api_key'], $options['apsl_twitter_settings']['apsl_twitter_api_secret'] );
                    $encoded_url = isset($_GET['redirect_to']) ? $_GET['redirect_to'] : '';
                    if(isset($encoded_url) && $encoded_url !=''){
                        $callback =$callBackUrl.'apsl_login_id'.'=twitter_check&redirect_to='.$encoded_url;
                    }else{
                        $callback =$callBackUrl.'apsl_login_id'.'=twitter_check';
                    }

                    $request_token 	= $twitterObj->getRequestToken($callback);
                    $_SESSION['oauth_twitter'] = array();

                    /* Save temporary credentials to session. */
                    $_SESSION['oauth_twitter']['oauth_token'] = $token = $request_token['oauth_token'];
                    $_SESSION['oauth_twitter']['oauth_token_secret'] = $request_token['oauth_token_secret'];

                    /* If last connection failed don't display authorization link. */
                    switch ($twitterObj->http_code) {
                        case 200:
                            try{
                                $url = $twitterObj->getAuthorizeUrl($token);
                                $this->redirect($url);
                            }catch(Exception $e){
                                $response->status 		= 'ERROR';
                                $response->error_code 	= 2;
                                $response->error_message= 'Could not get AuthorizeUrl.';
                            }
                        break;

                        default:
                            $response->status 		= 'ERROR';
                            $response->error_code 	= 2;
                            $response->error_message= 'Could not connect to Twitter. Refresh the page or try again later.';
                        break;
                    }

                }else{
                    $response->status 		= 'ERROR';
                    $response->error_code 	= 2;
                    $response->error_message= 'INVALID AUTHORIZATION';
                }
            }else if(isset($request['oauth_token']) && isset($request['oauth_verifier'])){

                /* Create TwitteroAuth object with app key/secret and token key/secret from default phase */
                $twitterObj = new TwitterOAuth($options['apsl_twitter_settings']['apsl_twitter_api_key'], $options['apsl_twitter_settings']['apsl_twitter_api_secret'], $_SESSION['oauth_twitter']['oauth_token'], $_SESSION['oauth_twitter']['oauth_token_secret']);			

                /* Remove no longer needed request tokens */
                unset($_SESSION['oauth_twitter']);
                try{
                    $access_token 		= $twitterObj->getAccessToken($request['oauth_verifier']);
                    /* If HTTP response is 200 continue otherwise send to connect page to retry */
                    if (200 == $twitterObj->http_code) {
                        $user_profile		= $twitterObj->get('users/show',array('screen_name'=>$access_token['screen_name'],'include_entities'=>true));

                        /* Request access twitterObj from twitter */
                        $response->status 		= 'SUCCESS';
                        $response->deuid		= $user_profile->id;
                        $response->deutype		= 'twitter';
                        $response->name			= explode(' ', $user_profile->name, 2);
                        $response->first_name	= $response->name[0];
                        $response->last_name	= (isset($response->name[1]))?$response->name[1]:'';
                        $response->deuimage 	= $user_profile->profile_image_url_https;
                        $response->email		= $user_profile->screen_name.'@twitter.com';
                        $response->username		= $user_profile->screen_name.'@twitter.com';
                        $response->url 			= $user_profile->url;
                        $response->about 		= $user_profile->description;
                        $response->gender 		= $user_profile->gender;
                        $response->location 	= $user_profile->location;
                        $response->error_message = '';
                    }else{
                        $response->status 		= 'ERROR';
                        $response->error_code 	= 2;
                        $response->error_message= 'Could not connect to Twitter. Refresh the page or try again later.';
                    }
                }catch(Exception $e){
                    $response->status 		= 'ERROR';
                    $response->error_code 	= 2;
                    $response->error_message= 'Could not get AccessToken.';
                }
            }else{ // User Canceled your Request
                $response->status 		= 'ERROR';
                $response->error_code 	= 1;
                $response->error_message= "USER CANCELED REQUEST";
            }
            return $response;
        }

        //for google login
        function onGoogleLogin(){
            $result = $this->GoogleLogin();
                if(isset($result->status) == 'SUCCESS'){
                    $row = $this->getUserByMail( $result->email);
                    $options = get_option( APSL_SETTINGS );
                    if(!$row){
                        $this->creatUser($result->username, $result->email);
                        $row = $this->getUserByMail($result->email);
                        update_user_meta($row->ID, 'email', $result->email);
                        update_user_meta($row->ID, 'first_name', $result->first_name);
                        update_user_meta($row->ID, 'last_name', $result->last_name);
                        update_user_meta($row->ID, 'deuid', $result->deuid);
                        update_user_meta($row->ID, 'deutype', $result->deutype);
                        update_user_meta($row->ID, 'deuimage', $result->deuimage);
                        update_user_meta($row->ID, 'description', $result->about);
                        wp_update_user( array ('ID' => $row->ID, 'display_name' => $result->first_name, 'role'=>$options['apsl_user_role'], 'user_url' => $result->url) ) ;
                    }
                    $this->loginUser($row->ID);
                }
        }

        function GoogleLogin(){
            $post 		= $_POST;
            $get  		= $_GET;
            $request 	= $_REQUEST;
            $site 		= $this->siteUrl();
            $callBackUrl= $this->callBackUrl();
            $options 	= get_option( APSL_SETTINGS );
            $response 	= new stdClass();
            $a			= explode('_', $_GET['apsl_login_id']);
            $action		= $a[1];
            $client_id		= $options['apsl_google_settings']['apsl_google_client_id'];
            $client_secret	= $options['apsl_google_settings']['apsl_google_client_secret'];

            $encoded_url = isset($_GET['redirect_to']) ? $_GET['redirect_to'] : '';
            $callback =$callBackUrl.'apsl_login_id'.'=google_check';

            $redirect_uri	= $callback;
            $client = new Google_Client;

            $client->setClientId($client_id);
            $client->setClientSecret($client_secret);
            $client->setRedirectUri($redirect_uri);
            $client->addScope("https://www.googleapis.com/auth/plus.profile.emails.read");
            if(isset($encoded_url) && $encoded_url !='') {
                $client->setState(base64_encode("redirect_to=$encoded_url"));
            } else {

            }
            $service = new Google_Service_Plus($client);
            if ($action == 'login'){// Get identity from user and redirect browser to OpenID Server
                if(!(isset($_SESSION['access_token']) && $_SESSION['access_token'])){
                    $authUrl = $client->createAuthUrl();
                    $this->redirect($authUrl);
                    die();
                }else{
                    $this->redirect($redirect_uri."&redirect_to=$encoded_url");
                    die();
                }

            }elseif(isset($_GET['code'])){ 	// Perform HTTP Request to OpenID server to validate key
                $client->authenticate($_GET['code']);
                $_SESSION['access_token'] 	= $client->getAccessToken();
                $this->redirect($redirect_uri."&redirect_to=$encoded_url");
                die();
            }elseif(isset($_SESSION['access_token']) && $_SESSION['access_token']){
                $client->setAccessToken($_SESSION['access_token']);

                try{
                    $user	= $service->people->get("me", array());
                }catch(Exception $fault){
                    unset($_SESSION['access_token']);
                    $ref_object = $this->accessProtected($fault, 'errors');
                    echo $ref_object[0]['message']." Please notify about this error to the Site Admin.";
                    die();
                }

                if(!empty($user)){
                    if(!empty($user->emails)){
                        $response->email    	= $user->emails[0]->value;
                        $response->username 	= $user->emails[0]->value;
                        $response->first_name	= $user->name->givenName;
                        $response->last_name	= $user->name->familyName;
                        $response->deuid		= $user->emails[0]->value;
                        $response->deuimage 	= $user->image->url;
                        $response->gender 		= $user->gender;
                        $response->id 			= $user->id;
                        $response->about 		= $user->aboutMe;
                        $response->url 			= $user->url;
                        $response->deutype		= 'google';
                        $response->status   	= 'SUCCESS';
                        $response->error_message = '';
                    }else{
                        $response->status = 'ERROR';
                        $response->error_code 	= 2;
                        $response->error_message = "INVALID AUTHORIZATION";
                    }
                }else{// Signature Verification Failed
                    $response->status = 'ERROR';
                    $response->error_code 	= 2;
                    $response->error_message = "INVALID AUTHORIZATION";
                }
            }elseif ($get['openid_mode'] == 'cancel'){ // User Canceled your Request
                $response->status = 'ERROR';
                $response->error_code 	= 1;
                $response->error_message = "USER CANCELED REQUEST";
            }else{ // User failed to login
                $response->status = 'ERROR';
                $response->error_code 	= 3;
                $response->error_message = "USER LOGIN FAIL";
            }
            return $response;
        }

        //other remaining methods
        function siteUrl(){
                return site_url();
        }

        function callBackUrl(){
            $connection = !empty($_SERVER['HTTPS']) ? 'https://' : 'http://';
            $url = $connection . $_SERVER["HTTP_HOST"] . $_SERVER["PHP_SELF"];
            if( strpos($url, '?')===false ){
                $url .= '?';
            }else{
                $url .= '&';
            }
            return $url;
        }

        //function to return json values from social media urls
        function get_json_values( $url ){
            $response = wp_remote_get( $url);
            $json_response = wp_remote_retrieve_body( $response );
            return $json_response;
        }

        function redirect( $redirect ){
            if (headers_sent()){ // Use JavaScript to redirect if content has been previously sent (not recommended, but safe)
                echo '<script language="JavaScript" type="text/javascript">window.location=\'';
                echo $redirect;
                echo '\';</script>';
            }else{	// Default Header Redirect
                header('Location: ' . $redirect);
            }
            exit;
        }

        function updateUser($username, $email){
            $row = $this->getUserByUsername ($username);
            if($row && $email!='' && $row->user_email!=$email){
                $row = (array) $row;
                $row['user_email']  = $email;
                wp_update_user($row);
            }
        }

        // Redefine user notification function
        function wp_new_user_notification( $user_id, $plaintext_pass = '' ) {
            $user = new WP_User($user_id);

            $user_login = stripslashes($user->user_login);
            $user_email = stripslashes($user->user_email);

            $message  = sprintf(__('New user registration on your blog %s:'), get_option('blogname')) . "\r\n\r\n";
            $message .= sprintf(__('Username: %s'), $user_login) . "\r\n\r\n";
            $message .= sprintf(__('E-mail: %s'), $user_email) . "\r\n";

            @wp_mail(get_option('admin_email'), sprintf(__('[%s] New User Registration'), get_option('blogname')), $message);

            if ( empty($plaintext_pass) )
                return;

            $message  = __('Hi there,') . "\r\n\r\n";
            $message .= sprintf(__("Welcome to %s! Here's how to log in:"), get_option('blogname')) . "\r\n\r\n";
            $message .= wp_login_url() . "\r\n";
            $message .= sprintf(__('Username: %s'), $user_login) . "\r\n";
            $message .= sprintf(__('Password: %s'), $plaintext_pass) . "\r\n\r\n";
            $message .= sprintf(__('If you have any problems, please contact me at %s.'), get_option('admin_email')) . "\r\n\r\n";
            $message .= __('Adios!');

            wp_mail($user_email, sprintf(__('[%s] Your username and password'), get_option('blogname')), $message);

        }

        function getUserByMail($email){
            global $wpdb;
            $row = $wpdb->get_row("SELECT * FROM $wpdb->users WHERE user_email = '$email'");
            if($row){
                return $row;
            }
            return false;
        }

        function getUserByUsername ($username){
            global $wpdb;
            $row = $wpdb->get_row("SELECT * FROM $wpdb->users WHERE user_login = '$username'");
            if($row){
                return $row;
            }
            return false;
        }

        function creatUser($user_name, $user_email){
            $random_password = wp_generate_password(12, false);
            $user_id = wp_create_user( $user_name, $random_password, $user_email );
            $options = get_option( APSL_SETTINGS );
            if($options['apsl_send_email_notification_options'] == 'yes'){
                wp_new_user_notification( $user_id, $random_password );
            }
            return $user_id;
        }

        function set_cookies($user_id = 0, $remember = true) {
            if (!function_exists('wp_set_auth_cookie')){
              return false;
            }
            if (!$user_id){
              return false;
            }
            wp_clear_auth_cookie();
            wp_set_auth_cookie($user_id, $remember);
            wp_set_current_user($user_id);
            return true;
        }

        function loginUser($user_id){

            $current_url_an = get_permalink();
            $reauth = empty($_REQUEST['reauth']) ? false : true;
            if ( $reauth )
                wp_clear_auth_cookie();

            if ( isset( $_REQUEST['redirect_to'] ) ) {
                $redirect_to = $_REQUEST['redirect_to'];
                // Redirect to https if user wants ssl
                if ( isset($secure_cookie) && false !== strpos($redirect_to, 'wp-admin') )
                    $redirect_to = preg_replace('|^http://|', 'https://', $redirect_to);
            } else {
                $redirect_to = admin_url();
            }
            if ( !isset($secure_cookie) && is_ssl() && force_ssl_login() && !force_ssl_admin() && ( 0 !== strpos($redirect_to, 'https') ) && ( 0 === strpos($redirect_to, 'http') ) )
            $secure_cookie = false;

            // If cookies are disabled we can't log in even with a valid user+pass
            if ( isset($_POST['testcookie']) && empty($_COOKIE[TEST_COOKIE]) )
                $user = new WP_Error('test_cookie', __("<strong>ERROR</strong>: Cookies are blocked or not supported by your browser. You must <a href='http://www.google.com/cookies.html'>enable cookies</a> to use WordPress."));
            else
                $user = wp_signon('', isset($secure_cookie));

            if(!$this->set_cookies($user_id)){
                return false;
            }
            $requested_redirect_to = isset( $_REQUEST['redirect_to'] ) ? $_REQUEST['redirect_to'] : site_url();
            $user_login_url = apply_filters( 'login_redirect', $redirect_to, $requested_redirect_to, $user );

            $options = get_option( APSL_SETTINGS );
            if(isset($options['apsl_custom_login_redirect_options']) && $options['apsl_custom_login_redirect_options'] !=''){
                    if($options['apsl_custom_login_redirect_options'] =='home'){
                        $user_login_url =  home_url();

                    }else if($options['apsl_custom_login_redirect_options'] =='current_page'){
                        if ( isset( $_REQUEST['redirect_to'] ) ) {
                            $redirect_to = $_REQUEST['redirect_to'];
                            // Redirect to https if user wants ssl
                            if ( isset($secure_cookie) && false !== strpos($redirect_to, 'wp-admin') )
                                $user_login_url = preg_replace('|^http://|', 'https://', $redirect_to);
                        } else {
                            $user_login_url = home_url();
                        }

                    }else if( $options['apsl_custom_login_redirect_options'] == 'custom_page' ){
                        if( $options['apsl_custom_login_redirect_link'] !='' ){
                            $login_page = $options['apsl_custom_login_redirect_link'];
                            $user_login_url = $login_page;
                        }else{
                            $user_login_url = home_url();
                        }
                    }
            }else{
                $user_login_url = home_url();
            }
            $redirect_to = $user_login_url;
            wp_safe_redirect( $redirect_to );
            exit();
        }

        //returns the current page url
        public static function curPageURL() {
            $pageURL = 'http';
            if ( isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on' ) {
                $pageURL .= "s";
            }
            $pageURL .= "://";
            if ( $_SERVER["SERVER_PORT"] != "80" ) {
                $pageURL .= $_SERVER["SERVER_NAME"] . ":" . $_SERVER["SERVER_PORT"] . $_SERVER["REQUEST_URI"];
            } else {
                $pageURL .= $_SERVER["SERVER_NAME"] . $_SERVER["REQUEST_URI"];
            }
            return $pageURL;
        }

        //function to access the protected object properties
        function accessProtected($obj, $prop) {
            $reflection = new ReflectionClass($obj);
            $property = $reflection->getProperty($prop);
            $property->setAccessible(true);
            return $property->getValue($obj);
        }

    } //termination of a class

} //end of if statement

$apsl_login_check = new APSL_Lite_Login_Check_Class();

inc/frontend/shortcode.php

<?php defined( 'ABSPATH' ) or die( 'No script kiddies please!' ); ?>
<?php $options = get_option( APSL_SETTINGS ); ?>
<?php
if (is_user_logged_in()){
	global $current_user;
	$user_info 	= "<span class='display-name'>{$current_user->data->display_name}</span> ";
	$user_info  .= get_avatar( $current_user->ID, 20 );
	$current_url = APSL_Lite_Login_Check_Class::curPageURL();
	if(isset($options['apsl_custom_logout_redirect_options']) && $options['apsl_custom_logout_redirect_options'] !=''){
		if($options['apsl_custom_logout_redirect_options'] =='home'){
			$user_logout_url = wp_logout_url( home_url() );
		}else if($options['apsl_custom_logout_redirect_options'] =='current_page'){
			$user_logout_url = wp_logout_url( $current_url );

		}else if( $options['apsl_custom_logout_redirect_options'] == 'custom_page' ){
			if( $options['apsl_custom_logout_redirect_link'] !='' ){
				$logout_page = $options['apsl_custom_logout_redirect_link'];
				$user_logout_url = wp_logout_url($logout_page);
			}else{
				$user_logout_url = wp_logout_url( $current_url );
			}
		}

	}else{
		$user_logout_url = wp_logout_url( $current_url );
	}
	?><div class="user-login">Welcome <b><?php echo $user_info; ?></b> | <a href="<?php echo $user_logout_url; ?>" title="Logout">Logout</a></div>
	<?php
}else{
?>
<?php
	$current_url = APSL_Lite_Login_Check_Class::curPageURL();
	$encoded_url = urlencode($current_url);
?>

<?php $theme = $options['apsl_icon_theme']; ?>

<div class='apsl-login-networks theme-<?php echo $theme; ?> clearfix'>
	<?php if(isset($attr['login_text']) && $attr['login_text']!=''){ ?>
	<span class='apsl-login-new-text'><?php echo $attr['login_text']; ?></span>
	<?php } ?>
	<?php if(isset($_REQUEST['error']) || isset($_REQUEST['denied'])){ ?>
			<div class='apsl-error'><?php _e('You have Access Denied. Please authorize the app to login.', APSL_TEXT_DOMAIN ); ?></div>
	<?php } ?>
	<div class='social-networks'>
		<?php foreach($options['network_ordering'] as $key=>$value): ?>
		<?php	if($options["apsl_{$value}_settings"]["apsl_{$value}_enable"]==='enable'){ ?>
		 <a href="?apsl_login_id=<?php echo $value; ?>_login<?php if ($encoded_url) { echo "&state=".base64_encode("redirect_to=$encoded_url"); } ?>" title='<?php _e('Login with', APSL_TEXT_DOMAIN ); echo ' '.$value; ?>'>
			 	<div class="apsl-icon-block icon-<?php echo $value; ?>">
					<i class="fa fa-<?php echo $value; ?>"></i>
					<span class="apsl-login-text"><?php _e('Login', APSL_TEXT_DOMAIN ); ?></span>
					<span class="apsl-long-login-text"><?php _e('Login with', APSL_TEXT_DOMAIN ); ?><?php echo ' '.$value; ?></span>
				</div>
		 </a>
			<?php } ?>
		<?php endforeach; ?>
 	</div>
</div>
<?php }