Discourse::sso_parse_request PHP Method

    function sso_parse_request($wp)
    {
        $discourse_options = self::get_plugin_options();
        // sync logout from Discourse to WordPress from Adam Capirola : https://meta.discourse.org/t/wordpress-integration-guide/27531
        // to make this work, enter a URL of the form "http://my-wp-blog.com/?request=logout" in the "logout redirect"
        // field in your Discourse admin
        if (isset($discourse_options['enable-sso']) && intval($discourse_options['enable-sso']) == 1 && isset($_GET['request']) && $_GET['request'] == 'logout') {
            wp_logout();
            wp_redirect($discourse_options['url']);
            exit;
        }
        // end logout processing
        // only process requests with "my-plugin=ajax-handler"
        if (isset($discourse_options['enable-sso']) && intval($discourse_options['enable-sso']) == 1 && array_key_exists('sso', $wp->query_vars) && array_key_exists('sig', $wp->query_vars)) {
            // Not logged in to WordPress, redirect to WordPress login page with redirect back to here
            if (!is_user_logged_in()) {
                // Preserve sso and sig parameters
                $redirect = add_query_arg(null, null);
                // Change %0A to %0B so it's not stripped out in wp_sanitize_redirect
                $redirect = str_replace('%0A', '%0B', $redirect);
                // Build login URL
                $login = wp_login_url(esc_url_raw($redirect));
                // Redirect to login
                wp_redirect($login);
                exit;
            } else {
                // Check for helper class
                if (!class_exists('Discourse_SSO')) {
                    // Error message
                    echo 'Helper class is not properly included.';
                    exit;
                }
                // Payload and signature
                $payload = $wp->query_vars['sso'];
                $sig = $wp->query_vars['sig'];
                // Change %0B back to %0A
                $payload = urldecode(str_replace('%0B', '%0A', urlencode($payload)));
                // Validate signature
                $sso_secret = $discourse_options['sso-secret'];
                $sso = new Discourse_SSO($sso_secret);
                if (!$sso->validate($payload, $sig)) {
                    // Error message
                    echo 'Invalid request.';
                    exit;
                }
                // Nonce
                $nonce = $sso->get_nonce($payload);
                // Current user info
                $current_user = wp_get_current_user();
                // Map information
                $params = array('nonce' => $nonce, 'name' => $current_user->display_name, 'username' => $current_user->user_login, 'email' => $current_user->user_email, 'about_me' => $current_user->description, 'external_id' => $current_user->ID, 'avatar_url' => get_avatar_url(get_current_user_id()));
                // Build login string
                $q = $sso->build_login_string($params);
                // Redirect back to Discourse
                wp_redirect($discourse_options['url'] . '/session/sso_login?' . $q);
                exit;
            }
        }
    }