message_history-8.x-1.x-dev/message_history.module

<?php

/**
 * @file
 * Records which users have read which message.
 */

use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
use Drupal\Core\Entity\EntityInterface;
use Drupal\Core\Session\AccountInterface;

/**
 * Retrieves the timestamp for the current user's last view of a message.
 *
 * @param int $mid
 *   A message ID.
 *
 * @return int
 *   If a message has been previously viewed by the user, the timestamp in
 *   seconds of when the last view occurred; otherwise, zero.
 */
function message_history_read($mid) {
  $history = message_history_read_multiple([$mid]);
  return $history[$mid];
}

/**
 * Retrieves the last viewed timestamp for each of the passed message IDs.
 *
 * @param array $mids
 *   An array of message IDs.
 *
 * @return array
 *   Array of timestamps keyed by message ID. If a message has been previously
 *   viewed by the user, the timestamp in seconds of when the last view
 *   occurred; otherwise, zero.
 */
function message_history_read_multiple(array $mids = []) {
  $history = &drupal_static(__FUNCTION__, []);

  $return = [];

  $items_to_read = [];
  foreach ($mids as $mid) {
    if (isset($history[$mid])) {
      $return[$mid] = $history[$mid];
    }
    else {
      // Initialize value if current user has not viewed the message.
      $items_to_read[$mid] = 0;
    }
  }

  if (empty($items_to_read)) {
    return $return;
  }

  // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
  // You will need to use `\Drupal\core\Database\Database::getConnection()` if you do not yet have access to the container here.
  $result = \Drupal::database()->query('SELECT mid, timestamp FROM {message_history} WHERE uid = :uid AND mid IN ( :mids[] )', [
    ':uid' => \Drupal::currentUser()->id(),
    ':mids[]' => array_keys($items_to_read),
  ]);
  foreach ($result as $row) {
    $items_to_read[$row->mid] = (int) $row->timestamp;
  }
  $history += $items_to_read;

  return $return + $items_to_read;
}

/**
 * Updates 'last viewed' timestamp of the specified entity for the current user.
 *
 * @param int $mid
 *   The message ID that has been read.
 * @param \Drupal\Core\Session\AccountInterface $account
 *   (optional) The user account to update the message history for. Defaults to
 *   the current user.
 */
function message_history_write($mid, AccountInterface $account = NULL) {
  if (!isset($account)) {
    $account = \Drupal::currentUser();
  }

  if ($account->isAuthenticated()) {
    // You will need to use `\Drupal\core\Database\Database::getConnection()` if you do not yet have access to the container here.
    \Drupal::database()->merge('message_history')
      ->keys([
        'uid' => $account->id(),
        'mid' => $mid,
      ])
      ->fields(['timestamp' => \Drupal::time()->getRequestTime()])
      ->execute();
    // Update static cache.
    $history = &drupal_static('message_history_read_multiple', []);
    $history[$mid] = \Drupal::time()->getRequestTime();
  }
}

/**
 * Implements hook_cron().
 */
function message_history_cron() {
  // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
  // You will need to use `\Drupal\core\Database\Database::getConnection()` if you do not yet have access to the container here.
  \Drupal::database()->delete('message_history')
    ->condition('timestamp', \HISTORY_READ_LIMIT, '<')
    ->execute();
}

/**
 * Implements hook_ENTITY_TYPE_view_alter() for message entities.
 */
function message_history_message_view_alter(array &$build, EntityInterface $message, EntityViewDisplayInterface $display) {
  // Update the message_history table, stating that this user viewed this
  // message.
  // @todo: make displays configurable.
  if (!in_array($display->getOriginalMode(), ['default', 'full'])) {
    return;
  }
  $build['#cache']['contexts'][] = 'user.roles:authenticated';
  if (!\Drupal::currentUser()->isAuthenticated()) {
    return;
  }
  // When the window's "load" event is triggered, mark the messafe as read.
  // This still allows for Drupal behaviors (which are triggered on the
  // "DOMContentReady" event) to add "new" and "updated" indicators.
  $build['#attached']['library'][] = 'message_history/mark-as-read';
  $build['#attached']['drupalSettings']['message_history']['itemsToMarkAsRead'][$message->id()] = TRUE;
}

/**
 * Implements hook_ENTITY_TYPE_delete() for message entities.
 */
function message_history_message_delete(EntityInterface $message) {
  // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
  // You will need to use `\Drupal\core\Database\Database::getConnection()` if you do not yet have access to the container here.
  \Drupal::database()->delete('message_history')
    ->condition('mid', $message->id())
    ->execute();
}

/**
 * Implements hook_user_cancel().
 */
function message_history_user_cancel($edit, $account, $method) {
  switch ($method) {
    case 'user_cancel_reassign':
      // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
      // You will need to use `\Drupal\core\Database\Database::getConnection()` if you do not yet have access to the container here.
      \Drupal::database()->delete('message_history')
        ->condition('uid', $account->id())
        ->execute();
      break;
  }
}

/**
 * Implements hook_ENTITY_TYPE_delete() for user entities.
 */
function message_history_user_delete($account) {
  // TODO: Drupal Rector Notice: Please delete the following comment after you've made any necessary changes.
  // You will need to use `\Drupal\core\Database\Database::getConnection()` if you do not yet have access to the container here.
  \Drupal::database()->delete('message_history')
    ->condition('uid', $account->id())
    ->execute();
}

/**
 * Creates #lazy_builder callback for the last read timestamp for a message.
 *
 * @param int $message_id
 *   The message ID for which to attach the last read timestamp.
 *
 * @return array
 *   A renderable array containing the last read timestamp.
 */
function message_history_attach_timestamp($message_id) {
  $element = [];
  $element['#attached']['drupalSettings']['message_history']['lastReadTimestamps'][$message_id] = (int) message_history_read($message_id);
  return $element;
}