source: extensions/oAuth/include/test/examples/signin_signup/application/controllers/authentications.php @ 20293

<?php
class authentications extends controller {
        function authenticatewith( $provider )
        {
                // set on application.config.php
                GLOBAL $hybridauth_config;

                try{
                // create an instance for Hybridauth with the configuration file path as parameter
                        $hybridauth = new Hybrid_Auth( $hybridauth_config );

                // try to authenticate the selected $provider
                        $adapter = $hybridauth->authenticate( $provider );

                // grab the user profile
                        $user_profile = $adapter->getUserProfile();

                // load user and authentication models, we will need them...
                        $authentication = $this->loadModel( "authentication" );
                        $user = $this->loadModel( "user" );

                # 1 - check if user already have authenticated using this provider before
                        $authentication_info = $authentication->find_by_provider_uid( $provider, $user_profile->identifier );

                # 2 - if authentication exists in the database, then we set the user as connected and redirect him to his profile page
                        if( $authentication_info ){
                                // 2.1 - store user_id in session
                                $_SESSION["user"] = $authentication_info["user_id"]; 

                                // 2.2 - redirect to user/profile
                                $this->redirect( "users/profile" );
                        }

                # 3 - else, here lets check if the user email we got from the provider already exists in our database ( for this example the email is UNIQUE for each user )
                        // if authentication does not exist, but the email address returned  by the provider does exist in database, 
                        // then we tell the user that the email  is already in use 
                        // but, its up to you if you want to associate the authentication with the user having the adresse email in the database
                        if( $user_profile->email ){
                                $user_info = $user->find_by_email( $user_profile->email );

                                if( $user_info ) {
                                        die( '<br /><b style="color:red">Well! the email returned by the provider ('. $user_profile->email .') already exist in our database, so in this case you might use the <a href="index.php?route=users/login">Sign-in</a> to login using your email and password.</b>' );
                                }
                        }

                # 4 - if authentication does not exist and email is not in use, then we create a new user 
                        $provider_uid  = $user_profile->identifier;
                        $email         = $user_profile->email;
                        $first_name    = $user_profile->firstName;
                        $last_name     = $user_profile->lastName;
                        $display_name  = $user_profile->displayName;
                        $website_url   = $user_profile->webSiteURL;
                        $profile_url   = $user_profile->profileURL;
                        $password      = rand( ) ; # for the password we generate something random

                        // 4.1 - create new user
                        $new_user_id = $user->create( $email, $password, $first_name, $last_name ); 

                        // 4.2 - creat a new authentication for him
                        $authentication->create( $new_user_id, $provider, $provider_uid, $email, $display_name, $first_name, $last_name, $profile_url, $website_url );
 
                        // 4.3 - store the new user_id in session
                        $_SESSION["user"] = $new_user_id;

                        // 4.4 - redirect to user/profile
                        $this->redirect( "users/profile" );
                }
                catch( Exception $e ){
                        // Display the recived error
                        switch( $e->getCode() ){ 
                                case 0 : $error = "Unspecified error."; break;
                                case 1 : $error = "Hybriauth configuration error."; break;
                                case 2 : $error = "Provider not properly configured."; break;
                                case 3 : $error = "Unknown or disabled provider."; break;
                                case 4 : $error = "Missing provider application credentials."; break;
                                case 5 : $error = "Authentication failed. The user has canceled the authentication or the provider refused the connection."; break;
                                case 6 : $error = "User profile request failed. Most likely the user is not connected to the provider and he should to authenticate again."; 
                                             $adapter->logout(); 
                                             break;
                                case 7 : $error = "User not connected to the provider."; 
                                             $adapter->logout(); 
                                             break;
                        } 

                        // well, basically your should not display this to the end user, just give him a hint and move on..
                        $error .= "<br /><br /><b>Original error message:</b> " . $e->getMessage(); 
                        $error .= "<hr /><pre>Trace:<br />" . $e->getTraceAsString() . "</pre>"; 

                        // load error view
                        $data = array( "error" => $error ); 
                        $this->loadView( "pages/error", $data );
                }
        }
}