function book_block

Implementation of hook_block().

Displays the book table of contents in a block when the current page is a single-node view of a book node.

File

modules/book/book.module, line 152

Allows users to collaboratively author a book.

Code

function book_block($op = 'list', $delta = 0) {
  $block = array();
  if ($op == 'list') {
    $block[0]['info'] = t('Book navigation');
    return $block;
  }
  else {
    if ($op == 'view') {

      // Only display this block when the user is browsing a book:
      if (arg(0) == 'node' && is_numeric(arg(1))) {
        $result = db_query(db_rewrite_sql('SELECT n.nid, n.title, b.parent FROM {node} n INNER JOIN {book} b ON n.vid = b.vid WHERE n.nid = %d'), arg(1));
        if (db_num_rows($result) > 0) {
          $node = db_fetch_object($result);
          $path = book_location($node);
          $path[] = $node;
          $expand = array();
          foreach ($path as $key => $node) {
            $expand[] = $node->nid;
          }
          $block['subject'] = check_plain($path[0]->title);
          $block['content'] = book_tree($expand[0], 5, $expand);
        }
      }
      return $block;
    }
  }
}