modules/comment/comment.module

<?php
// $Id: comment.module,v 1.799 2009/11/02 23:20:28 webchick Exp $

/**
 * @file
 * Enables users to comment on published content.
 *
 * When enabled, the Drupal comment module creates a discussion
 * board for each Drupal node. Users can post comments to discuss
 * a forum topic, weblog post, story, collaborative book page, etc.
 */

/**
 * Comment is awaiting approval.
 */
define('COMMENT_NOT_PUBLISHED', 0);

/**
 * Comment is published.
 */
define('COMMENT_PUBLISHED', 1);

/**
 * Comments are displayed in a flat list - expanded.
 */
define('COMMENT_MODE_FLAT', 0);

/**
 * Comments are displayed as a threaded list - expanded.
 */
define('COMMENT_MODE_THREADED', 1);

/**
 * Anonymous posters cannot enter their contact information.
 */
define('COMMENT_ANONYMOUS_MAYNOT_CONTACT', 0);

/**
 * Anonymous posters may leave their contact information.
 */
define('COMMENT_ANONYMOUS_MAY_CONTACT', 1);

/**
 * Anonymous posters are required to leave their contact information.
 */
define('COMMENT_ANONYMOUS_MUST_CONTACT', 2);

/**
 * Comment form should be displayed on a separate page.
 */
define('COMMENT_FORM_SEPARATE_PAGE', 0);

/**
 * Comment form should be shown below post or list of comments.
 */
define('COMMENT_FORM_BELOW', 1);

/**
 * Comments for this node are hidden.
 */
define('COMMENT_NODE_HIDDEN', 0);

/**
 * Comments for this node are closed.
 */
define('COMMENT_NODE_CLOSED', 1);

/**
 * Comments for this node are open.
 */
define('COMMENT_NODE_OPEN', 2);

/**
 * Implement hook_help().
 */
function comment_help($path, $arg) {
  switch ($path) {
    case 'admin/help#comment':
      $output  = '<p>' . t('The comment module allows visitors to comment on your posts, creating ad hoc discussion boards. Any <a href="@content-type">content type</a> may have its <em>Default comment setting</em> set to <em>Open</em> to allow comments, <em>Hidden</em> to hide existing comments and prevent new comments or <em>Closed</em> to allow existing comments to be viewed but no new comments added. Comment display settings and other controls may also be customized for each content type.', array('@content-type' => url('admin/structure/types'))) . '</p>';
      $output .= '<p>' . t('Comment permissions are assigned to user roles, and are used to determine whether anonymous users (or other roles) are allowed to comment on posts. If anonymous users are allowed to comment, their individual contact information may be retained in cookies stored on their local computer for use in later comment submissions. When a comment has no replies, it may be (optionally) edited by its author. The comment module uses the same text formats and HTML tags available when creating other forms of content.') . '</p>';
      $output .= '<p>' . t('Change comment settings on the content type\'s <a href="@content-type">edit page</a>.', array('@content-type' => url('admin/structure/types'))) . '</p>';
      $output .= '<p>' . t('For more information, see the online handbook entry for <a href="@comment">Comment module</a>.', array('@comment' => 'http://drupal.org/handbook/modules/comment/')) . '</p>';

      return $output;
  }
}

/**
 * Implement hook_entity_info().
 */
function comment_entity_info() {
  $return =  array(
    'comment' => array(
      'label' => t('Comment'),
      'base table' => 'comment',
      'fieldable' => TRUE,
      'controller class' => 'CommentController',
      'object keys' => array(
        'id' => 'cid',
        'bundle' => 'node_type',
      ),
      'bundle keys' => array(
        'bundle' => 'type',
      ),
      'bundles' => array(),
      'static cache' => FALSE,
    ),
  );

  foreach (node_type_get_names() as $type => $name) {
    $return['comment']['bundles']['comment_node_' . $type] = array(
      'label' => $name,
    );
  }

  return $return;
}

/**
 * Implement hook_theme().
 */
function comment_theme() {
  return array(
    'comment_block' => array(
      'variables' => array(),
    ),
    'comment_preview' => array(
      'variables' => array('comment' => NULL),
    ),
    'comment' => array(
      'template' => 'comment',
      'render element' => 'elements',
    ),
    'comment_post_forbidden' => array(
      'variables' => array('node' => NULL),
    ),
    'comment_wrapper' => array(
      'template' => 'comment-wrapper',
      'render element' => 'content',
    ),
  );
}

/**
 * Implement hook_menu().
 */
function comment_menu() {
  $items['admin/content/comment'] = array(
    'title' => 'Comments',
    'description' => 'List and edit site comments and the comment approval queue.',
    'page callback' => 'comment_admin',
    'access arguments' => array('administer comments'),
    'type' => MENU_LOCAL_TASK,
    'file' => 'comment.admin.inc',
  );
  // Tabs begin here.
  $items['admin/content/comment/new'] = array(
    'title' => 'Published comments',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/content/comment/approval'] = array(
    'title' => 'Unapproved comments',
    'title callback' => 'comment_count_unpublished',
    'page arguments' => array('approval'),
    'access arguments' => array('administer comments'),
    'type' => MENU_LOCAL_TASK,
  );
  $items['comment/%comment'] = array(
    'title' => 'Comment permalink',
    'page callback' => 'comment_permalink',
    'page arguments' => array(1),
    'access arguments' => array('access comments'),
    'type' => MENU_CALLBACK,
  );
  $items['comment/%comment/view'] = array(
    'title' => 'View comment',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['comment/%comment/edit'] = array(
    'title' => 'Edit',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('comment_form', 1),
    'access callback' => 'comment_access',
    'access arguments' => array('edit', 1),
    'type' => MENU_LOCAL_TASK,
    'context' => MENU_CONTEXT_PAGE | MENU_CONTEXT_INLINE,
    'weight' => 0,
  );
  $items['comment/%comment/approve'] = array(
    'title' => 'Approve',
    'page callback' => 'comment_approve',
    'page arguments' => array(1),
    'access arguments' => array('administer comments'),
    'type' => MENU_LOCAL_TASK,
    'context' => MENU_CONTEXT_INLINE,
    'file' => 'comment.pages.inc',
    'weight' => 1,
  );
  $items['comment/%comment/delete'] = array(
    'title' => 'Delete',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('comment_confirm_delete', 1),
    'access arguments' => array('administer comments'),
    'type' => MENU_LOCAL_TASK,
    'context' => MENU_CONTEXT_PAGE | MENU_CONTEXT_INLINE,
    'file' => 'comment.admin.inc',
    'weight' => 2,
  );
  $items['comment/reply/%node'] = array(
    'title' => 'Add new comment',
    'page callback' => 'comment_reply',
    'page arguments' => array(2),
    'access callback' => 'node_access',
    'access arguments' => array('view', 2),
    'type' => MENU_CALLBACK,
    'file' => 'comment.pages.inc',
  );

  return $items;
}

/**
 * Returns a menu title which includes the number of unapproved comments.
 */
function comment_count_unpublished() {
  $count = db_query('SELECT COUNT(cid) FROM {comment} WHERE status = :status', array(
    ':status' => COMMENT_NOT_PUBLISHED,
  ))->fetchField();
  return t('Unapproved comments (@count)', array('@count' => $count));
}

/**
 * Implement hook_node_type_insert().
 */
function comment_node_type_insert($info) {
  field_attach_create_bundle('comment', 'comment_node_' . $info->type);
}

/**
 * Implement hook_node_type_update().
 */
function comment_node_type_update($info) {
  if (!empty($info->old_type) && $info->type != $info->old_type) {
    field_attach_rename_bundle('comment', 'comment_node_' . $info->old_type, 'comment_node_' . $info->type);
  }
}

/**
 * Implement hook_node_type_delete().
 */
function comment_node_type_delete($info) {
  field_attach_delete_bundle('comment', 'comment_node_' . $info->type);
  $settings = array(
    'comment',
    'comment_default_mode',
    'comment_default_per_page',
    'comment_anonymous',
    'comment_subject_field',
    'comment_preview',
    'comment_form_location',
  );
  foreach ($settings as $setting) {
    variable_del($setting . '_' . $info->type);
  }
}

/**
 * Implement hook_permission().
 */
function comment_permission() {
  return array(
    'administer comments' => array(
      'title' => t('Administer comments'),
      'description' => t('Manage and approve comments, and configure comment administration settings.'),
    ),
    'access comments' => array(
      'title' => t('Access comments'),
      'description' => t('View comments attached to content.'),
    ),
    'post comments' => array(
      'title' => t('Post comments'),
      'description' => t('Add comments to content (approval required).'),
    ),
    'post comments without approval' => array(
      'title' => t('Post comments without approval'),
      'description' => t('Add comments to content (no approval required).'),
    ),
  );
}

/**
 * Implement hook_block_info().
 */
function comment_block_info() {
  $blocks['recent']['info'] = t('Recent comments');

  return $blocks;
}

/**
 * Implement hook_block_configure().
 */
function comment_block_configure($delta = '') {
  $form['comment_block_count'] = array(
    '#type' => 'select',
    '#title' => t('Number of recent comments'),
    '#default_value' => variable_get('comment_block_count', 10),
    '#options' => drupal_map_assoc(array(2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30)),
  );

  return $form;
}

/**
 * Implement hook_block_save().
 */
function comment_block_save($delta = '', $edit = array()) {
  variable_set('comment_block_count', (int)$edit['comment_block_count']);
}

/**
 * Implement hook_block_view().
 *
 * Generates a block with the most recent comments.
 */
function comment_block_view($delta = '') {
  if (user_access('access comments')) {
    $block['subject'] = t('Recent comments');
    $block['content'] = theme('comment_block');

    return $block;
  }
}

/**
 * Redirects comment links to the correct page depending on comment settings.
 *
 * Since comments are paged there is no way to guarantee which page a comment
 * appears on. Comment paging and threading settings may be changed at any time.
 * With threaded comments, an individual comment may move between pages as
 * comments can be added either before or after it in the overall discussion.
 * Therefore we use a central routing function for comment links, which
 * calculates the page number based on current comment settings and returns
 * the full comment view with the pager set dynamically.
 *
 * @param $comment
 *   A comment object.
 * @return
 *   The comment listing set to the page on which the comment appears.
 */
function comment_permalink($comment) {
  $node = node_load($comment->nid);
  if ($node && $comment) {

    // Find the current display page for this comment.
    $page = comment_get_display_page($comment->cid, $node->type);

    // Set $_GET['q'] and $_GET['page'] ourselves so that the node callback
    // behaves as it would when visiting the page directly.
    $_GET['q'] = 'node/' . $node->nid;
    $_GET['page'] = $page;

    // Return the node view, this will show the correct comment in context.
    return menu_execute_active_handler('node/' . $node->nid, FALSE);
  }
  drupal_not_found();
}

/**
 * Find the most recent comments that are available to the current user.
 *
 * This is done in two steps:
 *   1. Query the {node_comment_statistics} table to find n number of nodes that
 *      have the most recent comments. This table is indexed on
 *      last_comment_timestamp, thus making it a fast query.
 *   2. Load the information from the comments table based on the nids found
 *      in step 1.
 *
 * @param integer $number
 *   (optional) The maximum number of comments to find.
 * @return
 *   An array of comment objects each containing a nid, subject, cid, created
 *   and changed, or an empty array if there are no recent comments visible
 *   to the current user.
 */
function comment_get_recent($number = 10) {
  // Step 1: Select a $number of nodes which have new comments,
  //         and are visible to the current user.
  $nids = db_query_range("SELECT nc.nid FROM {node_comment_statistics} nc WHERE nc.comment_count > 0 ORDER BY nc.last_comment_timestamp DESC", 0, $number)->fetchCol();

  $comments = array();
  if (!empty($nids)) {
    // Step 2: From among the comments on the nodes selected in the first query,
    //         find the $number of most recent comments.
    // Using Query Builder here for the IN-Statement.
    $query = db_select('comment', 'c');
    $query->innerJoin('node', 'n', 'n.nid = c.nid');
    return $query
      ->fields('c', array('nid', 'subject', 'cid', 'created', 'changed'))
      ->condition('c.nid', $nids, 'IN')
      ->condition('c.status', COMMENT_PUBLISHED)
      ->condition('n.status', 1)
      ->orderBy('c.cid', 'DESC')
      ->range(0, $number)
      ->execute()
      ->fetchAll();
  }

  return $comments;
}

/**
 * Calculate page number for first new comment.
 *
 * @param $num_comments
 *   Number of comments.
 * @param $new_replies
 *   Number of new replies.
 * @param $node
 *   The first new comment node.
 * @return
 *   "page=X" if the page number is greater than zero; empty string otherwise.
 */
function comment_new_page_count($num_comments, $new_replies, stdClass $node) {
  $mode = variable_get('comment_default_mode_' . $node->type, COMMENT_MODE_THREADED);
  $comments_per_page = variable_get('comment_default_per_page_' . $node->type, 50);
  $pagenum = NULL;
  $flat = $mode == COMMENT_MODE_FLAT ? TRUE : FALSE;
  if ($num_comments <= $comments_per_page) {
    // Only one page of comments.
    $pageno = 0;
  }
  elseif ($flat) {
    // Flat comments.
    $count = $num_comments - $new_replies;
    $pageno =  $count / $comments_per_page;
  }
  else {
    // Threaded comments.
    // Find the first thread with a new comment.
    $result = db_query_range('SELECT thread FROM (SELECT thread
      FROM {comment}
      WHERE nid = :nid
        AND status = 0
      ORDER BY changed DESC) AS thread
      ORDER BY SUBSTRING(thread, 1, (LENGTH(thread) - 1))', 0, $new_replies, array(':nid' => $node->nid))->fetchField();
    $thread = substr($result, 0, -1);
    $count = db_query('SELECT COUNT(*) FROM {comment} WHERE nid = :nid AND status = 0 AND SUBSTRING(thread, 1, (LENGTH(thread) - 1)) < :thread', array(
      ':nid' => $node->nid,
      ':thread' => $thread,
    ))->fetchField();
    $pageno =  $count / $comments_per_page;
  }

  if ($pageno >= 1) {
    $pagenum = array('page' => intval($pageno));
  }

  return $pagenum;
}

/**
 * Returns a formatted list of recent comments to be displayed in the comment block.
 *
 * @return
 *   The comment list HTML.
 * @ingroup themeable
 */
function theme_comment_block() {
  $items = array();
  $number = variable_get('comment_block_count', 10);
  foreach (comment_get_recent($number) as $comment) {
    $items[] = l($comment->subject, 'comment/' . $comment->cid, array('fragment' => 'comment-' . $comment->cid)) . '<br />' . t('@time ago', array('@time' => format_interval(REQUEST_TIME - $comment->changed)));
  }

  if ($items) {
    return theme('item_list', array('items' => $items));
  }
}

/**
 * Implement hook_node_view().
 */
function comment_node_view(stdClass $node, $build_mode) {
  $links = array();

  if ($node->comment) {
    if ($build_mode == 'rss') {
      if ($node->comment != COMMENT_NODE_HIDDEN) {
        // Add a comments RSS element which is a URL to the comments of this node.
        $node->rss_elements[] = array(
          'key' => 'comments',
          'value' => url('node/' . $node->nid, array('fragment' => 'comments', 'absolute' => TRUE))
        );
      }
    }
    elseif ($build_mode == 'teaser') {
      // Main page: display the number of comments that have been posted.
      if (user_access('access comments')) {
        if (!empty($node->comment_count)) {
          $links['comment_comments'] = array(
            'title' => format_plural($node->comment_count, '1 comment', '@count comments'),
            'href' => "node/$node->nid",
            'attributes' => array('title' => t('Jump to the first comment of this posting.')),
            'fragment' => 'comments',
            'html' => TRUE,
          );

          $new = comment_num_new($node->nid);
          if ($new) {
            $links['comment_new_comments'] = array(
              'title' => format_plural($new, '1 new comment', '@count new comments'),
              'href' => "node/$node->nid",
              'query' => comment_new_page_count($node->comment_count, $new, $node),
              'attributes' => array('title' => t('Jump to the first new comment of this posting.')),
              'fragment' => 'new',
              'html' => TRUE,
            );
          }
        }
        else {
          if ($node->comment == COMMENT_NODE_OPEN) {
            if (user_access('post comments')) {
              $links['comment_add'] = array(
                'title' => t('Add new comment'),
                'href' => "comment/reply/$node->nid",
                'attributes' => array('title' => t('Add a new comment to this page.')),
                'fragment' => 'comment-form',
                'html' => TRUE,
              );
            }
            else {
              $links['comment_forbidden']['title'] = theme('comment_post_forbidden', array('node' => $node));
            }
          }
        }
      }
    }
    else {
      // Node page: add a "post comment" link if the user is allowed to post
      // comments and if this node is not read-only.
      if ($node->comment == COMMENT_NODE_OPEN) {
        if (user_access('post comments')) {
          $links['comment_add'] = array(
            'title' => t('Add new comment'),
            'attributes' => array('title' => t('Share your thoughts and opinions related to this posting.')),
            'fragment' => 'comment-form',
            'html' => TRUE,
          );
          if (variable_get('comment_form_location_' . $node->type, COMMENT_FORM_BELOW) == COMMENT_FORM_SEPARATE_PAGE) {
            $links['comment_add']['href'] = "comment/reply/$node->nid";
          }
          else {
            $links['comment_add']['href'] = "node/$node->nid";
          }
        }
        else {
          $links['comment_forbidden']['title'] = theme('comment_post_forbidden', array('node' => $node));
        }
      }
    }

    if (isset($links['comment_forbidden'])) {
      $links['comment_forbidden']['html'] = TRUE;
    }

    $node->content['links']['comment'] = array(
      '#theme' => 'links',
      '#links' => $links,
      '#attributes' => array('class' => array('links', 'inline')),
    );

    // Only append comments when we are building a node on its own node detail
    // page. We compare $node and $page_node to ensure that comments are not
    // appended to other nodes shown on the page, for example a node_reference
    // displayed in 'full' build mode within another node.
    $page_node = menu_get_object();
    if ($node->comment && isset($page_node->nid) && $page_node->nid == $node->nid && empty($node->in_preview) && user_access('access comments')) {
      $node->content['comments'] = comment_node_page_additions($node);
    }
  }
}

/**
 * Build the comment-related elements for node detail pages.
 *
 * @param $node
 *  A node object.
 */
function comment_node_page_additions(stdClass $node) {
  $additions = array();

  // Only attempt to render comments if the node has visible comments.
  // Unpublished comments are not included in $node->comment_count, so show
  // comments unconditionally if the user is an administrator.
  if ($node->comment_count || user_access('administer comments')) {
    $mode = variable_get('comment_default_mode_' . $node->type, COMMENT_MODE_THREADED);
    $comments_per_page = variable_get('comment_default_per_page_' . $node->type, 50);
    if ($cids = comment_get_thread($node, $mode, $comments_per_page)) {
      $comments = comment_load_multiple($cids);
      comment_prepare_thread($comments);
      $build = comment_build_multiple($comments, $node);
      $build['#attached']['css'][] = drupal_get_path('module', 'comment') . '/comment.css';
      $build['pager']['#theme'] = 'pager';
      $additions['comments'] = $build;
    }
  }

  // Append comment form if needed.
  if (user_access('post comments') && $node->comment == COMMENT_NODE_OPEN && (variable_get('comment_form_location_' . $node->type, COMMENT_FORM_BELOW) == COMMENT_FORM_BELOW)) {
    $build = drupal_get_form('comment_form', (object) array('nid' => $node->nid));
    $additions['comment_form'] = $build;
  }

  if ($additions) {
    $additions += array(
      '#theme' => 'comment_wrapper',
      '#node' => $node,
      'comments' => array(),
      'comment_form' => array(),
    );
  }

  return $additions;
}

/**
 * Retrieve comments for a thread.
 *
 * @param $node
 *   The node whose comment(s) needs rendering.
 * @param $mode
 *   The comment display mode; COMMENT_MODE_FLAT or COMMENT_MODE_THREADED.
 * @param $comments_per_page
 *   The amount of comments to display per page.
 *
 * To display threaded comments in the correct order we keep a 'thread' field
 * and order by that value. This field keeps this data in
 * a way which is easy to update and convenient to use.
 *
 * A "thread" value starts at "1". If we add a child (A) to this comment,
 * we assign it a "thread" = "1.1". A child of (A) will have "1.1.1". Next
 * brother of (A) will get "1.2". Next brother of the parent of (A) will get
 * "2" and so on.
 *
 * First of all note that the thread field stores the depth of the comment:
 * depth 0 will be "X", depth 1 "X.X", depth 2 "X.X.X", etc.
 *
 * Now to get the ordering right, consider this example:
 *
 * 1
 * 1.1
 * 1.1.1
 * 1.2
 * 2
 *
 * If we "ORDER BY thread ASC" we get the above result, and this is the
 * natural order sorted by time. However, if we "ORDER BY thread DESC"
 * we get:
 *
 * 2
 * 1.2
 * 1.1.1
 * 1.1
 * 1
 *
 * Clearly, this is not a natural way to see a thread, and users will get
 * confused. The natural order to show a thread by time desc would be:
 *
 * 2
 * 1
 * 1.2
 * 1.1
 * 1.1.1
 *
 * which is what we already did before the standard pager patch. To achieve
 * this we simply add a "/" at the end of each "thread" value. This way, the
 * thread fields will look like this:
 *
 * 1/
 * 1.1/
 * 1.1.1/
 * 1.2/
 * 2/
 *
 * we add "/" since this char is, in ASCII, higher than every number, so if
 * now we "ORDER BY thread DESC" we get the correct order. However this would
 * spoil the reverse ordering, "ORDER BY thread ASC" -- here, we do not need
 * to consider the trailing "/" so we use a substring only.
 */
function comment_get_thread(stdClass $node, $mode, $comments_per_page) {
  $query = db_select('comment', 'c')->extend('PagerDefault');
  $query->addField('c', 'cid');
  $query
    ->condition('c.nid', $node->nid)
    ->addTag('node_access')
    ->limit($comments_per_page);

  $count_query = db_select('comment', 'c');
  $count_query->addExpression('COUNT(*)');
  $count_query
    ->condition('c.nid', $node->nid)
    ->addTag('node_access');

  if (!user_access('administer comments')) {
    $query->condition('c.status', COMMENT_PUBLISHED);
    $count_query->condition('c.status', COMMENT_PUBLISHED);
  }
  if ($mode === COMMENT_MODE_FLAT) {
    $query->orderBy('c.cid', 'ASC');
  }
  else {
    // See comment above. Analysis reveals that this doesn't cost too
    // much. It scales much much better than having the whole comment
    // structure.
    $query->orderBy('SUBSTRING(c.thread, 1, (LENGTH(c.thread) - 1))', 'ASC');
  }

  $query->setCountQuery($count_query);
  $cids = $query->execute()->fetchCol();

  return $cids;
}

/**
 * Loop over comment thread, noting indentation level.
 *
 * @param array $comments
 *   An array of comment objects, keyed by cid.
 * @return
 *   The $comments argument is altered by reference with indentation information.
 */
function comment_prepare_thread(&$comments) {
  // A flag stating if we are still searching for first new comment on the thread.
  $first_new = TRUE;

  // A counter that helps track how indented we are.
  $divs = 0;

  foreach ($comments as $key => $comment) {
    if ($first_new && $comment->new != MARK_READ) {
      // Assign the anchor only for the first new comment. This avoids duplicate
      // id attributes on a page.
      $first_new = FALSE;
      $comment->first_new = TRUE;
    }

    // The $divs element instructs #prefix whether to add an indent div or
    // close existing divs (a negative value).
    $comment->depth = count(explode('.', $comment->thread)) - 1;
    if ($comment->depth > $divs) {
      $comment->divs = 1;
      $divs++;
    }
    else {
      $comment->divs = $comment->depth - $divs;
      while ($comment->depth < $divs) {
        $divs--;
      }
    }
    $comments[$key] = $comment;
  }

  // The final comment must close up some hanging divs
  $comments[$key]->divs_final = $divs;
}

/**
 * Generate an array for rendering the given comment.
 *
 * @param $comment
 *   A comment object.
 * @param $node
 *   The node the comment is attached to.
 * @param $build_mode
 *   Build mode, e.g. 'full', 'teaser'...
 *
 * @return
 *   An array as expected by drupal_render().
 */
function comment_build($comment, stdClass $node, $build_mode = 'full') {
  // Populate $comment->content with a render() array.
  comment_build_content($comment, $node, $build_mode);

  $build = $comment->content;
  // We don't need duplicate rendering info in comment->content.
  unset($comment->content);

  $build += array(
    '#theme' => 'comment',
    '#comment' => $comment,
    '#node' => $node,
    '#build_mode' => $build_mode,
  );
  // Add contextual links for this comment.
  $build['#contextual_links']['comment'] = menu_contextual_links('comment', array($comment->cid));

  $prefix = '';
  $is_threaded = isset($comment->divs) && variable_get('comment_default_mode_' . $node->type, COMMENT_MODE_THREADED) == COMMENT_MODE_THREADED;

  // Add 'new' anchor if needed.
  if (!empty($comment->first_new)) {
    $prefix .= "<a id=\"new\"></a>\n";
  }

  // Add indentation div or close open divs as needed.
  if ($is_threaded) {
    $prefix .= $comment->divs <= 0 ? str_repeat('</div>', abs($comment->divs)) : "\n" . '<div class="indented">';
  }

  // Add anchor for each comment.
  $prefix .= "<a id=\"comment-$comment->cid\"></a>\n";
  $build['#prefix'] = $prefix;

  // Close all open divs.
  if ($is_threaded && !empty($comment->divs_final)) {
    $build['#suffix'] = str_repeat('</div>', $comment->divs_final);
  }

  return $build;
}

/**
 * Builds a structured array representing the comment's content.
 *
 * The content built for the comment (field values, comments, file attachments or
 * other comment components) will vary depending on the $build_mode parameter.
 *
 * @param $comment
 *   A comment object.
 * @param $node
 *   The node the comment is attached to.
 * @param $build_mode
 *   Build mode, e.g. 'full', 'teaser'...
 */
function comment_build_content($comment, stdClass $node, $build_mode = 'full') {
  // Remove previously built content, if exists.
  $comment->content = array();

  // Build comment body.
  $comment->content['comment_body'] = array(
    '#markup' => check_markup($comment->comment, $comment->format, '', TRUE),
  );

  field_attach_prepare_view('comment', array($comment->cid => $comment), $build_mode);
  $comment->content += field_attach_view('comment', $comment, $build_mode);

  if (empty($comment->in_preview)) {
    $comment->content['links']['comment'] = array(
      '#theme' => 'links',
      '#links' => comment_links($comment, $node),
      '#attributes' => array('class' => array('links', 'inline')),
    );
  }

  // Allow modules to make their own additions to the comment.
  module_invoke_all('comment_view', $comment, $build_mode);

  // Allow modules to modify the structured comment.
  drupal_alter('comment_build', $comment, $build_mode);
}

/**
 * Helper function, build links for an individual comment.
 *
 * Adds reply, edit, delete etc. depending on the current user permissions.
 *
 * @param $comment
 *   The comment object.
 * @param $node
 *   The node the comment is attached to.
 * @return
 *   A structured array of links.
 */
function comment_links($comment, stdClass $node) {
  $links = array();
  if ($node->comment == COMMENT_NODE_OPEN) {
    if (user_access('administer comments') && user_access('post comments')) {
      $links['comment_delete'] = array(
        'title' => t('delete'),
        'href' => "comment/$comment->cid/delete",
        'html' => TRUE,
      );
      $links['comment_edit'] = array(
        'title' => t('edit'),
        'href' => "comment/$comment->cid/edit",
        'html' => TRUE,
      );
      $links['comment_reply'] = array(
        'title' => t('reply'),
        'href' => "comment/reply/$comment->nid/$comment->cid",
        'html' => TRUE,
      );
      if ($comment->status == COMMENT_NOT_PUBLISHED) {
        $links['comment_approve'] = array(
          'title' => t('approve'),
          'href' => "comment/$comment->cid/approve",
          'html' => TRUE,
        );
      }
    }
    elseif (user_access('post comments')) {
      if (comment_access('edit', $comment)) {
        $links['comment_edit'] = array(
          'title' => t('edit'),
          'href' => "comment/$comment->cid/edit",
          'html' => TRUE,
        );
      }
      $links['comment_reply'] = array(
        'title' => t('reply'),
        'href' => "comment/reply/$comment->nid/$comment->cid",
        'html' => TRUE,
      );
    }
    else {
      $links['comment_forbidden']['title'] = theme('comment_post_forbidden', array('node' => $node));
      $links['comment_forbidden']['html'] = TRUE;
    }
  }
  return $links;
}

/**
 * Construct a drupal_render() style array from an array of loaded comments.
 *
 * @param $comments
 *   An array of comments as returned by comment_load_multiple().
 * @param $node
 *   The node the comments are attached to.
 * @param $build_mode
 *   Build mode, e.g. 'full', 'teaser'...
 * @param $weight
 *   An integer representing the weight of the first comment in the list.
 * @return
 *   An array in the format expected by drupal_render().
 */
function comment_build_multiple($comments, stdClass $node, $build_mode = 'full', $weight = 0) {
  field_attach_prepare_view('comment', $comments, $build_mode);

  $build = array(
    '#sorted' => TRUE,
  );
  foreach ($comments as $comment) {
    $build[$comment->cid] = comment_build($comment, $node, $build_mode);
    $build[$comment->cid]['#weight'] = $weight;
    $weight++;
  }
  return $build;
}

/**
 * Implement hook_form_FORM_ID_alter().
 */
function comment_form_node_type_form_alter(&$form, $form_state) {
  if (isset($form['identity']['type'])) {
    $form['comment'] = array(
      '#type' => 'fieldset',
      '#title' => t('Comment settings'),
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      '#group' => 'additional_settings',
      '#attached' => array(
        'js' => array(drupal_get_path('module', 'comment') . '/comment-node-form.js'),
      ),
    );
    $form['comment']['comment_default_mode'] = array(
      '#type' => 'checkbox',
      '#title' => t('Threading'),
      '#default_value' => variable_get('comment_default_mode_' . $form['#node_type']->type, COMMENT_MODE_THREADED),
      '#description' => t('Show comment replies in a threaded list.'),
    );
    $form['comment']['comment_default_per_page'] = array(
      '#type' => 'select',
      '#title' => t('Comments per page'),
      '#default_value' => variable_get('comment_default_per_page_' . $form['#node_type']->type, 50),
      '#options' => _comment_per_page(),
    );

    $form['comment']['comment'] = array(
      '#type' => 'select',
      '#title' => t('Default comment setting for new content'),
      '#default_value' => variable_get('comment_' . $form['#node_type']->type, COMMENT_NODE_OPEN),
      '#options' => array(t('Hidden'), t('Closed'), t('Open')),
    );
    $form['comment']['comment_anonymous'] = array(
      '#type' => 'select',
      '#title' => t('Anonymous commenting'),
      '#default_value' => variable_get('comment_anonymous_' . $form['#node_type']->type, COMMENT_ANONYMOUS_MAYNOT_CONTACT),
      '#options' => array(
        COMMENT_ANONYMOUS_MAYNOT_CONTACT => t('Anonymous posters may not enter their contact information'),
        COMMENT_ANONYMOUS_MAY_CONTACT => t('Anonymous posters may leave their contact information'),
        COMMENT_ANONYMOUS_MUST_CONTACT => t('Anonymous posters must leave their contact information'))
    );

    if (!user_access('post comments', drupal_anonymous_user())) {
      $form['comment']['comment_anonymous']['#access'] = FALSE;
    }

    $form['comment']['comment_subject_field'] = array(
      '#type' => 'checkbox',
      '#title' => t('Allow comment title'),
      '#default_value' => variable_get('comment_subject_field_' . $form['#node_type']->type, 1),
    );
    $form['comment']['comment_form_location'] = array(
      '#type' => 'checkbox',
      '#title' => t('Show reply form on the same page as comments'),
      '#default_value' => variable_get('comment_form_location_' . $form['#node_type']->type, COMMENT_FORM_BELOW),
    );
    $form['comment']['comment_preview'] = array(
      '#type' => 'radios',
      '#title' => t('Preview comment'),
      '#default_value' => variable_get('comment_preview_' . $form['#node_type']->type, DRUPAL_OPTIONAL),
      '#options' => array(
        DRUPAL_DISABLED => t('Disabled'),
        DRUPAL_OPTIONAL => t('Optional'),
        DRUPAL_REQUIRED => t('Required'),
      ),
    );
  }
}

/**
 * Implement hook_form_alter().
 */
function comment_form_alter(&$form, $form_state, $form_id) {
  if (!empty($form['#node_edit_form'])) {
    $node = $form['#node'];
    $form['comment_settings'] = array(
      '#type' => 'fieldset',
      '#access' => user_access('administer comments'),
      '#title' => t('Comment settings'),
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      '#group' => 'additional_settings',
      '#attached' => array(
        'js' => array(drupal_get_path('module', 'comment') . '/comment-node-form.js'),
       ),
      '#weight' => 30,
    );
    $comment_count = isset($node->nid) ? db_query('SELECT comment_count FROM {node_comment_statistics} WHERE nid = :nid', array(':nid' => $node->nid))->fetchField() : 0;
    $comment_settings = ($node->comment == COMMENT_NODE_HIDDEN && empty($comment_count)) ? COMMENT_NODE_CLOSED : $node->comment;
    $form['comment_settings']['comment'] = array(
      '#type' => 'radios',
      '#parents' => array('comment'),
      '#default_value' => $comment_settings,
      '#options' => array(
        COMMENT_NODE_OPEN => t('Open'),
        COMMENT_NODE_CLOSED => t('Closed'),
        COMMENT_NODE_HIDDEN => t('Hidden'),
      ),
      COMMENT_NODE_OPEN => array(
        '#type' => 'radio',
        '#title' => t('Open'),
        '#description' => t('Users with the "Post comments" permission can post comments.'),
        '#return_value' => COMMENT_NODE_OPEN,
        '#default_value' => $comment_settings,
        '#id' => 'edit-comment-2',
        '#parents' => array('comment'),
      ),
      COMMENT_NODE_CLOSED => array(
        '#type' => 'radio',
        '#title' => t('Closed'),
        '#description' => t('Users cannot post comments, but existing comments will be displayed.'),
        '#return_value' => COMMENT_NODE_CLOSED,
        '#default_value' => $comment_settings,
        '#id' => 'edit-comment-1',
        '#parents' => array('comment'),
      ),
      COMMENT_NODE_HIDDEN => array(
        '#type' => 'radio',
        '#title' => t('Hidden'),
        '#description' => t('Comments are hidden from view.'),
        '#return_value' => COMMENT_NODE_HIDDEN,
        '#default_value' => $comment_settings,
        '#id' => 'edit-comment-0',
        '#parents' => array('comment'),
      ),
    );
    // If the node doesn't have any comments, the "hidden" option makes no
    // sense, so don't even bother presenting it to the user.
    if (empty($comment_count)) {
      unset($form['comment_settings']['comment']['#options'][COMMENT_NODE_HIDDEN]);
      unset($form['comment_settings']['comment'][COMMENT_NODE_HIDDEN]);
      $form['comment_settings']['comment'][COMMENT_NODE_CLOSED]['#description'] = t('Users cannot post comments.');
    }
  }
}

/**
 * Implement hook_node_load().
 */
function comment_node_load($nodes, $types) {
  $comments_enabled = array();

  // Check if comments are enabled for each node. If comments are disabled,
  // assign values without hitting the database.
  foreach ($nodes as $node) {
    // Store whether comments are enabled for this node.
    if ($node->comment != COMMENT_NODE_HIDDEN) {
      $comments_enabled[] = $node->nid;
    }
    else {
      $node->last_comment_timestamp = $node->created;
      $node->last_comment_name = '';
      $node->comment_count = 0;
    }
  }

  // For nodes with comments enabled, fetch information from the database.
  if (!empty($comments_enabled)) {
    $result = db_query('SELECT nid, last_comment_timestamp, last_comment_name, comment_count FROM {node_comment_statistics} WHERE nid IN(:comments_enabled)', array(':comments_enabled' => $comments_enabled));
    foreach ($result as $record) {
      $nodes[$record->nid]->last_comment_timestamp = $record->last_comment_timestamp;
      $nodes[$record->nid]->last_comment_name = $record->last_comment_name;
      $nodes[$record->nid]->comment_count = $record->comment_count;
    }
  }
}

/**
 * Implement hook_node_prepare().
 */
function comment_node_prepare(stdClass $node) {
  if (!isset($node->comment)) {
    $node->comment = variable_get("comment_$node->type", COMMENT_NODE_OPEN);
  }
}

/**
 * Implement hook_node_insert().
 */
function comment_node_insert(stdClass $node) {
  db_insert('node_comment_statistics')
    ->fields(array(
      'nid' => $node->nid,
      'last_comment_timestamp' => $node->changed,
      'last_comment_name' => NULL,
      'last_comment_uid' => $node->uid,
      'comment_count' => 0,
    ))
    ->execute();
}

/**
 * Implement hook_node_delete().
 */
function comment_node_delete(stdClass $node) {
  $cids = db_query('SELECT cid FROM {comment} WHERE nid = :nid', array(':nid' => $node->nid))->fetchCol();
  comment_delete_multiple($cids);
  db_delete('node_comment_statistics')
    ->condition('nid', $node->nid)
    ->execute();
}

/**
 * Implement hook_node_update_index().
 */
function comment_node_update_index(stdClass $node) {
  $text = '';
  if ($node->comment != COMMENT_NODE_HIDDEN) {
    $comments = db_query('SELECT subject, comment, format FROM {comment} WHERE nid = :nid AND status = :status', array(
      ':nid' => $node->nid,
      ':status' => COMMENT_PUBLISHED
    ));
    foreach ($comments as $comment) {
      $text .= '<h2>' . check_plain($comment->subject) . '</h2>' . check_markup($comment->comment, $comment->format, '', TRUE);
    }
  }
  return $text;
}

/**
 * Implement hook_update_index().
 */
function comment_update_index() {
  // Store the maximum possible comments per thread (used for ranking by reply count)
  variable_set('node_cron_comments_scale', 1.0 / max(1, db_query('SELECT MAX(comment_count) FROM {node_comment_statistics}')->fetchField()));
}

/**
 * Implement hook_node_search_result().
 */
function comment_node_search_result(stdClass $node) {
  if ($node->comment != COMMENT_NODE_HIDDEN) {
    $comments = db_query('SELECT comment_count FROM {node_comment_statistics} WHERE nid = :nid', array('nid' => $node->nid))->fetchField();
    return format_plural($comments, '1 comment', '@count comments');
  }
  return '';
}

/**
 * Implement hook_user_cancel().
 */
function comment_user_cancel($edit, $account, $method) {
  switch ($method) {
    case 'user_cancel_block_unpublish':
      db_update('comment')
        ->fields(array('status' => 0))
        ->condition('uid', $account->uid)
        ->execute();