SpamBotWebformHandler.php

<?php

namespace Drupal\spambot\Plugin\WebformHandler;

use Drupal\Component\Render\FormattableMarkup;
use Drupal\Component\Utility\Unicode;
use Drupal\Core\Extension\ModuleHandlerInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Url;
use Drupal\webform\Plugin\WebformElement\WebformCompositeBase;
use Drupal\webform\Plugin\WebformElementManagerInterface;
use Drupal\webform\Plugin\WebformHandlerBase;
use Drupal\Component\Utility\Html;
use Drupal\webform\WebformSubmissionInterface;
use Drupal\Core\StringTranslation\StringTranslationTrait;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpFoundation\Request;

/**
 * Webform validate handler.
 *
 * @WebformHandler(
 *   id = "spambot_validation",
 *   label = @Translation("Spambot Validation"),
 *   category = @Translation("Settings"),
 *   description = @Translation("Validate webform submissions with spambot service."),
 *   cardinality = \Drupal\webform\Plugin\WebformHandlerInterface::CARDINALITY_SINGLE,
 *   results = \Drupal\webform\Plugin\WebformHandlerInterface::RESULTS_PROCESSED,
 *   submission = \Drupal\webform\Plugin\WebformHandlerInterface::SUBMISSION_OPTIONAL,
 * )
 */
class SpamBotWebformHandler extends WebformHandlerBase {
    use StringTranslationTrait;
    
    /**
     * The webform element plugin manager.
     *
     * @var \Drupal\webform\Plugin\WebformElementManagerInterface
     */
    protected WebformElementManagerInterface $elementManager;
    
    /**
     * Current active request object.
     *
     * @var \Symfony\Component\HttpFoundation\Request
     */
    protected Request $request;
    
    /**
     * The module handler.
     *
     * @var \Drupal\Core\Extension\ModuleHandlerInterface
     */
    protected ModuleHandlerInterface $moduleHandler;
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        $instance = parent::create($container, $configuration, $plugin_id, $plugin_definition);
        $instance->elementManager = $container->get('plugin.manager.webform.element');
        $instance->request = $container->get('request_stack')
            ->getCurrentRequest();
        $instance->moduleHandler = $container->get('module_handler');
        return $instance;
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateForm(array &$form, FormStateInterface $form_state, WebformSubmissionInterface $webform_submission) {
        $config = $this->configFactory
            ->get('spambot.settings');
        if ($form_state->getErrors()) {
            return;
        }
        $email_threshold = $config->get('spambot_criteria_email');
        $username_threshold = $config->get('spambot_criteria_username');
        $ip_threshold = $config->get('spambot_criteria_ip');
        $data = $webform_submission->getData();
        $request = [];
        if ($this->configuration['email_field'] && $data[$this->configuration['email_field']]) {
            $request['email'] = $data[$this->configuration['email_field']];
        }
        if ($this->configuration['username_field'] && $data[$this->configuration['username_field']]) {
            $request['username'] = $data[$this->configuration['username_field']];
        }
        $ip = $this->request
            ->getClientIp();
        if ($ip_threshold > 0 && $ip != '127.0.0.1' && !spambot_check_whitelist('ip', $config, $ip)) {
            // Make sure we have a valid IPv4 address (API doesn't support IPv6 yet).
            if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4 | FILTER_FLAG_IPV6) === FALSE) {
                $this->getLogger('spambot')
                    ->notice('Invalid IP address on webform: @ip. Spambot will not rely on it.', [
                    '@ip' => $ip,
                ]);
            }
            else {
                $request['ip'] = $ip;
            }
        }
        $data = [];
        if (spambot_sfs_request($request, $data)) {
            $substitutions = [
                '@email' => $request['email'] ?? '',
                '%email' => $request['email'] ?? '',
                '@username' => $request['username'] ?? '',
                '%username' => $request['username'] ?? '',
                '@ip' => $ip,
                '%ip' => $ip,
            ];
            $reasons = [];
            if ($email_threshold > 0 && !empty($data['email']['appears']) && $data['email']['frequency'] >= $email_threshold) {
                $form_state->setErrorByName($this->configuration['email_field'], (string) $this->t($config->get('spambot_blocked_message_email'), $substitutions));
                $reasons[] = t('email=@value', [
                    '@value' => $request['email'],
                ]);
            }
            if ($username_threshold > 0 && !empty($data['username']['appears']) && $data['username']['frequency'] >= $username_threshold) {
                $form_state->setErrorByName($this->configuration['username_field'], (string) $this->t($config->get('spambot_blocked_message_username'), $substitutions));
                $reasons[] = t('username=@value', [
                    '@value' => $request['username'],
                ]);
            }
            if ($ip_threshold > 0 && !empty($data['ip']['appears']) && $data['ip']['frequency'] >= $ip_threshold) {
                $form_state->setErrorByName('', (string) $this->t($config->get('spambot_blocked_message_ip'), $substitutions));
                $reasons[] = t('ip=@value', [
                    '@value' => $request['ip'],
                ]);
            }
            if ($reasons) {
                if ($config->get('spambot_log_blocked_registration')) {
                    $this->getLogger('spambot')
                        ->notice('Blocked webform submission: @reasons', [
                        '@reasons' => implode(',', $reasons),
                    ]);
                    $hook_args = [
                        'request' => $request,
                        'reasons' => $reasons,
                    ];
                    $this->moduleHandler
                        ->invokeAll('spambot_registration_blocked', [
                        $hook_args,
                    ]);
                }
                if ($delay = $config->get('spambot_blacklisted_delay')) {
                    sleep($delay);
                }
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function defaultConfiguration() {
        return [
            'email_field' => '',
            'username_field' => '',
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
        $form['test'] = [
            '#type' => 'markup',
            '#markup' => $this->t('Other spambot settings can be <a href="@url">configured globally</a>.', [
                '@url' => Url::fromRoute('spambot.settings_form')->toString(TRUE)
                    ->getGeneratedUrl(),
            ]),
        ];
        $form['email_field'] = [
            '#type' => 'select',
            '#options' => $this->getEmailFields(),
            '#title' => $this->t('Email Field to validate'),
            '#empty_option' => $this->t('- NONE -'),
            '#default_value' => $this->configuration['email_field'],
        ];
        $form['username_field'] = [
            '#type' => 'select',
            '#options' => $this->getUsernameFields(),
            '#empty_option' => $this->t('- NONE -'),
            '#title' => $this->t('Username Field to validate'),
            '#default_value' => $this->configuration['username_field'],
            '#description' => $this->t('Be careful about using this option as you may accidentally block genuine users who happen to choose the same username as a known spammer.'),
        ];
        return $this->setSettingsParents($form);
    }
    
    /**
     * Get potential email fields.
     *
     * @return string[]
     *   Potential email field titles keyed by machine name.
     */
    protected function getEmailFields() : array {
        $mail_elements = [];
        $elements = $this->webform
            ->getElementsInitializedAndFlattened();
        foreach ($elements as $element_key => $element) {
            $element_plugin = $this->elementManager
                ->getElementInstance($element);
            if (!$element_plugin->isInput($element) || !isset($element['#type'])) {
                continue;
            }
            if ($element_plugin->hasMultipleValues($element)) {
                continue;
            }
            if (!$element_plugin->isComposite()) {
                if (in_array($element['#type'], [
                    'email',
                    'hidden',
                    'value',
                    'textfield',
                    'webform_email_multiple',
                    'webform_email_confirm',
                ])) {
                    $element_title = isset($element['#title']) ? new FormattableMarkup('@title (@key)', [
                        '@title' => $element['#title'],
                        '@key' => $element_key,
                    ]) : $element_key;
                    $mail_elements[$element_key] = $element_title;
                }
            }
        }
        return $mail_elements;
    }
    
    /**
     * Get potential username fields.
     *
     * @return string[]
     *   Potential username field titles keyed by machine name.
     */
    protected function getUsernameFields() {
        $username_elements = [];
        $elements = $this->webform
            ->getElementsInitializedAndFlattened();
        foreach ($elements as $element_key => $element) {
            $element_plugin = $this->elementManager
                ->getElementInstance($element);
            if (!$element_plugin->isInput($element) || !isset($element['#type'])) {
                continue;
            }
            if ($element_plugin->hasMultipleValues($element)) {
                continue;
            }
            if (!$element_plugin->isComposite()) {
                if (in_array($element['#type'], [
                    'hidden',
                    'value',
                    'textfield',
                ])) {
                    $element_title = isset($element['#title']) ? new FormattableMarkup('@title (@key)', [
                        '@title' => $element['#title'],
                        '@key' => $element_key,
                    ]) : $element_key;
                    $username_elements[$element_key] = $element_title;
                }
            }
        }
        return $username_elements;
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
        parent::submitConfigurationForm($form, $form_state);
        $this->configuration['email_field'] = $form_state->getValue('email_field');
        $this->configuration['username_field'] = $form_state->getValue('username_field');
    }
    
    /**
     * {@inheritdoc}
     */
    public function getSummary() {
        $summary = parent::getSummary();
        $email_fields = $this->getEmailFields();
        $username_fields = $this->getUsernameFields();
        $summary['#settings']['email_field'] = $email_fields[$this->configuration['email_field']] ?? $this->configuration['email_field'];
        $summary['#settings']['username_field'] = $username_fields[$this->configuration['username_field']] ?? $this->configuration['username_field'];
        return $summary;
    }

}