source: trunk/admin/include/functions.php @ 1064

<?php
// +-----------------------------------------------------------------------+
// | PhpWebGallery - a PHP based picture gallery                           |
// | Copyright (C) 2002-2003 Pierrick LE GALL - pierrick@phpwebgallery.net |
// | Copyright (C) 2003-2006 PhpWebGallery Team - http://phpwebgallery.net |
// +-----------------------------------------------------------------------+
// | branch        : BSF (Best So Far)
// | file          : $RCSfile$
// | last update   : $Date: 2006-03-04 23:31:46 +0000 (Sat, 04 Mar 2006) $
// | last modifier : $Author: plg $
// | revision      : $Revision: 1064 $
// +-----------------------------------------------------------------------+
// | This program is free software; you can redistribute it and/or modify  |
// | it under the terms of the GNU General Public License as published by  |
// | the Free Software Foundation                                          |
// |                                                                       |
// | This program is distributed in the hope that it will be useful, but   |
// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
// | General Public License for more details.                              |
// |                                                                       |
// | You should have received a copy of the GNU General Public License     |
// | along with this program; if not, write to the Free Software           |
// | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
// | USA.                                                                  |
// +-----------------------------------------------------------------------+

include(PHPWG_ROOT_PATH.'admin/include/functions_metadata.php');

/**
 * returns an array with all picture files according to $conf['file_ext']
 *
 * @param string $dir
 * @return array
 */
function get_pwg_files($dir)
{
  global $conf;

  $pictures = array();
  if ($opendir = opendir($dir))
  {
    while ($file = readdir($opendir))
    {
      if (in_array(get_extension($file), $conf['file_ext']))
      {
        array_push($pictures, $file);
      }
    }
  }
  return $pictures;
}

/**
 * returns an array with all thumbnails according to $conf['picture_ext']
 * and $conf['prefix_thumbnail']
 *
 * @param string $dir
 * @return array
 */
function get_thumb_files($dir)
{
  global $conf;

  $prefix_length = strlen($conf['prefix_thumbnail']);

  $thumbnails = array();
  if ($opendir = @opendir($dir.'/thumbnail'))
  {
    while ($file = readdir($opendir))
    {
      if (in_array(get_extension($file), $conf['picture_ext'])
          and substr($file, 0, $prefix_length) == $conf['prefix_thumbnail'])
      {
        array_push($thumbnails, $file);
      }
    }
  }
  return $thumbnails;
}

/**
 * returns an array with representative picture files of a directory
 * according to $conf['picture_ext']
 *
 * @param string $dir
 * @return array
 */
function get_representative_files($dir)
{
  global $conf;

  $pictures = array();
  if ($opendir = @opendir($dir.'/pwg_representative'))
  {
    while ($file = readdir($opendir))
    {
      if (in_array(get_extension($file), $conf['picture_ext']))
      {
        array_push($pictures, $file);
      }
    }
  }
  return $pictures;
}

// The function delete_site deletes a site and call the function
// delete_categories for each primary category of the site
function delete_site( $id )
{
  // destruction of the categories of the site
  $query = '
SELECT id
  FROM '.CATEGORIES_TABLE.'
  WHERE site_id = '.$id.'
;';
  $result = pwg_query($query);
  $category_ids = array();
  while ($row = mysql_fetch_array($result))
  {
    array_push($category_ids, $row['id']);
  }
  delete_categories($category_ids);

  // destruction of the site
  $query = '
DELETE FROM '.SITES_TABLE.'
  WHERE id = '.$id.'
;';
  pwg_query($query);
}


// The function delete_categories deletes the categories identified by the
// (numeric) key of the array $ids. It also deletes (in the database) :
//    - all the elements of the category (delete_elements, see further)
//    - all the links between elements and this category
//    - all the restrictions linked to the category
// The function works recursively.
function delete_categories($ids)
{
  global $counts;

  if (count($ids) == 0)
  {
    return;
  }

  // add sub-category ids to the given ids : if a category is deleted, all
  // sub-categories must be so
  $ids = get_subcat_ids($ids);

  // destruction of all the related elements
  $query = '
SELECT image_id
  FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE is_storage = \'true\'
    AND category_id IN ('.
    wordwrap(
      implode(', ', $ids),
      80,
      "\n"
      ).
    ')
;';
  $result = pwg_query($query);
  $element_ids = array();
  while ($row = mysql_fetch_array($result))
  {
    array_push($element_ids, $row['image_id']);
  }
  delete_elements($element_ids);

  // destruction of the links between images and this category
  $query = '
DELETE FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE category_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // destruction of the access linked to the category
  $query = '
DELETE FROM '.USER_ACCESS_TABLE.'
  WHERE cat_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);
  
  $query = '
DELETE FROM '.GROUP_ACCESS_TABLE.'
  WHERE cat_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // source/destination links deletion
  $query = '
SELECT destination, source
  FROM '.CATEGORIES_LINK_TABLE.'
  WHERE source IN ('.implode(',', $ids).')
    OR destination IN ('.implode(',', $ids).')
;';
  $result = pwg_query($query);

  $sources_of = array();
  
  while ($row = mysql_fetch_array($result))
  {
    if (!isset($sources_of[ $row['destination'] ]))
    {
      $sources_of[ $row['destination'] ] = array();
    }

    array_push(
      $sources_of[ $row['destination'] ],
      $row['source']
      );
  }

  foreach ($sources_of as $destination => $sources)
  {
    delete_sources($destination, $sources);
  }

  update_category();

  // destruction of the category
  $query = '
DELETE FROM '.CATEGORIES_TABLE.'
  WHERE id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  if (isset($counts['del_categories']))
  {
    $counts['del_categories']+= count($ids);
  }
}

// The function delete_elements deletes the elements identified by the
// (numeric) values of the array $ids. It also deletes (in the database) :
//    - all the comments related to elements
//    - all the links between categories and elements
//    - all the favorites associated to elements
function delete_elements($ids)
{
  global $counts;

  if (count($ids) == 0)
  {
    return;
  }

  // destruction of the comments on the image
  $query = '
DELETE FROM '.COMMENTS_TABLE.'
  WHERE image_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // destruction of the links between images and this category
  $query = '
DELETE FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE image_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // destruction of the favorites associated with the picture
  $query = '
DELETE FROM '.FAVORITES_TABLE.'
  WHERE image_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // destruction of the rates associated to this element
  $query = '
DELETE FROM '.RATE_TABLE.'
  WHERE element_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // destruction of the rates associated to this element
  $query = '
DELETE FROM '.CADDIE_TABLE.'
  WHERE element_id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  // destruction of the image
  $query = '
DELETE FROM '.IMAGES_TABLE.'
  WHERE id IN (
'.wordwrap(implode(', ', $ids), 80, "\n").')
;';
  pwg_query($query);

  if (isset($counts['del_elements']))
  {
    $counts['del_elements']+= count($ids);
  }
}

// The delete_user function delete a user identified by the $user_id
// It also deletes :
//     - all the access linked to this user
//     - all the links to any group
//     - all the favorites linked to this user
//     - calculated permissions linked to the user
//     - all datas about notifications for the user
function delete_user($user_id)
{
  global $conf;

  // destruction of the access linked to the user
  $query = '
DELETE FROM '.USER_ACCESS_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // destruction of data notification by mail for this user
  $query = '
DELETE FROM '.USER_MAIL_NOTIFICATION_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // destruction of data RSS notification for this user
  $query = '
DELETE FROM '.USER_FEED_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // destruction of the group links for this user
  $query = '
DELETE FROM '.USER_GROUP_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // destruction of the favorites associated with the user
  $query = '
DELETE FROM '.FAVORITES_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // deletion of calculated permissions linked to the user
  $query = '
DELETE FROM '.USER_CACHE_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // deletion of phpwebgallery specific informations
  $query = '
DELETE FROM '.USER_INFOS_TABLE.'
  WHERE user_id = '.$user_id.'
;';
  pwg_query($query);

  // destruction of the user
  $query = '
DELETE FROM '.USERS_TABLE.'
  WHERE '.$conf['user_fields']['id'].' = '.$user_id.'
;';
  pwg_query($query);
}

/**
 * updates calculated informations about a set of categories : date_last and
 * nb_images. It also verifies that the representative picture is really
 * linked to the category. Optionnaly recursive.
 *
 * @param mixed category id
 * @param boolean recursive
 * @returns void
 */
function update_category($ids = 'all', $recursive = false)
{
  global $conf;

  // retrieving all categories to update
  $cat_ids = array();

  $query = '
SELECT id
  FROM '.CATEGORIES_TABLE;
  if (is_array($ids))
  {
    if ($recursive)
    {
      foreach ($ids as $num => $id)
      {
        if ($num == 0)
        {
          $query.= '
  WHERE ';
        }
        else
        {
          $query.= '
  OR    ';
        }
        $query.= 'uppercats REGEXP \'(^|,)'.$id.'(,|$)\'';
      }
    }
    else
    {
      $query.= '
  WHERE id IN ('.wordwrap(implode(', ', $ids), 80, "\n").')';
    }
  }
  $query.= '
;';
  $cat_ids = array_unique(array_from_query($query, 'id'));

  if (count($cat_ids) == 0)
  {
    return false;
  }

  // calculate informations about categories retrieved
  $query = '
SELECT category_id,
       COUNT(image_id) AS nb_images,
       MAX(date_available) AS date_last
  FROM '.IMAGES_TABLE.'
    INNER JOIN '.IMAGE_CATEGORY_TABLE.' ON id = image_id
  WHERE category_id IN ('.wordwrap(implode(', ', $cat_ids), 80, "\n").')
  GROUP BY category_id
;';
  $result = pwg_query($query);
  $datas = array();
  $query_ids = array();
  while ($row = mysql_fetch_array($result))
  {
    array_push($query_ids, $row['category_id']);
    
    array_push(
      $datas,
      array(
        'id'        => $row['category_id'],
        'date_last' => $row['date_last'],
        'nb_images' => $row['nb_images']
        )
      );
  }
  // if all links between a category and elements have disappeared, no line
  // is returned but the update must be done !
  foreach (array_diff($cat_ids, $query_ids) as $id)
  {
    array_push(
      $datas,
      array(
        'id'        => $id,
        'nb_images' => 0,
        )
      );
  }

  mass_updates(
    CATEGORIES_TABLE,
    array(
      'primary' => array('id'),
      'update'  => array('date_last', 'nb_images')
      ),
    $datas
    );

  // representative pictures
  if (count($cat_ids) > 0)
  {
    // find all categories where the setted representative is not possible :
    // the picture does not exist
    $query = '
SELECT c.id
  FROM '.CATEGORIES_TABLE.' AS c LEFT JOIN '.IMAGES_TABLE.' AS i
    ON c.representative_picture_id = i.id
  WHERE representative_picture_id IS NOT NULL
    AND c.id IN ('.wordwrap(implode(', ', $cat_ids), 80, "\n").')
    AND i.id IS NULL
;';
    $wrong_representant = array_from_query($query, 'id');

    if ($conf['allow_random_representative'])
    {
      if (count($wrong_representant) > 0)
      {
        $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET representative_picture_id = NULL
  WHERE id IN ('.wordwrap(implode(', ', $wrong_representant), 80, "\n").')
;';
        pwg_query($query);
      }
    }
    else
    {
      $to_null = array();
      $to_rand = array();

      if (count($wrong_representant) > 0)
      {
        // among the categories with an unknown representant, we dissociate
        // categories containing pictures and categories containing no
        // pictures. Indeed, the representant must set to NULL if no picture
        // in the category and set to a random picture otherwise.
        $query = '
SELECT id
  FROM '.CATEGORIES_TABLE.'
  WHERE id IN ('.wordwrap(implode(', ', $wrong_representant), 80, "\n").')
    AND nb_images = 0
;';
        $to_null = array_from_query($query, 'id');
        $to_rand = array_diff($wrong_representant, $to_null);
      }

      if (count($to_null) > 0)
      {
        $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET representative_picture_id = NULL
  WHERE id IN ('.wordwrap(implode(', ', $to_null), 80, "\n").')
;';
        pwg_query($query);
      }

      // If the random representant is not allowed, we need to find
      // categories with elements and with no representant. Those categories
      // must be added to the list of categories to set to a random
      // representant.
      $query = '
SELECT id
  FROM '.CATEGORIES_TABLE.'
  WHERE representative_picture_id IS NULL
    AND nb_images != 0
    AND id IN ('.wordwrap(implode(', ', $cat_ids), 80, "\n").')
;';
      $to_rand =
        array_unique(
          array_merge(
            $to_rand,
            array_from_query($query, 'id')
            )
          );

      if (count($to_rand) > 0)
      {
        set_random_representant($to_rand);
      }
    }
  }
}

function date_convert_back( $date )
{
  // date arrives at this format : YYYY-MM-DD
  // It must be transformed in DD/MM/YYYY
  if ( $date != '' )
  {
    list($year,$month,$day) = explode( '-', $date );
    return $day.'/'.$month.'/'.$year;
  }
  else
  {
    return '';
  }
}

/**
 * returns an array with relevant keywords found in the given string.
 *
 * Keywords must be separated by comma or space characters.
 *
 * @param string keywords_string
 * @return array
 */
function get_keywords($keywords_string)
{
  return
    array_unique(
      preg_split(
        '/[\s,]+/',
        $keywords_string
        )
      );
}

/**
 * returns an array containing sub-directories which can be a category,
 * recursive by default
 *
 * directories nammed "thumbnail", "pwg_high" or "pwg_representative" are
 * omitted
 *
 * @param string $basedir
 * @return array
 */
function get_fs_directories($path, $recursive = true)
{
  $dirs = array();

  if (is_dir($path))
  {
    if ($contents = opendir($path))
    {
      while (($node = readdir($contents)) !== false)
      {
        if (is_dir($path.'/'.$node)
            and $node != '.'
            and $node != '..'
            and $node != '.svn'
            and $node != 'thumbnail'
            and $node != 'pwg_high'
            and $node != 'pwg_representative')
        {
          array_push($dirs, $path.'/'.$node);
          if ($recursive)
          {
            $dirs = array_merge($dirs, get_fs_directories($path.'/'.$node));
          }
        }
      }
    }
  }

  return $dirs;
}

/**
 * inserts multiple lines in a table
 *
 * @param string table_name
 * @param array dbfields
 * @param array inserts
 * @return void
 */
function mass_inserts($table_name, $dbfields, $datas)
{
  // inserts all found categories
  $query = '
INSERT INTO '.$table_name.'
  ('.implode(',', $dbfields).')
   VALUES';
  foreach ($datas as $insert_id => $insert)
  {
    $query.= '
  ';
    if ($insert_id > 0)
    {
      $query.= ',';
    }
    $query.= '(';
    foreach ($dbfields as $field_id => $dbfield)
    {
      if ($field_id > 0)
      {
        $query.= ',';
      }

      if (!isset($insert[$dbfield]) or $insert[$dbfield] == '')
      {
        $query.= 'NULL';
      }
      else
      {
        $query.= "'".$insert[$dbfield]."'";
      }
    }
    $query.=')';
  }
  $query.= '
;';
  pwg_query($query);
}

/**
 * updates multiple lines in a table
 *
 * @param string table_name
 * @param array dbfields
 * @param array datas
 * @return void
 */
function mass_updates($tablename, $dbfields, $datas)
{
  // depending on the MySQL version, we use the multi table update or N
  // update queries
  $query = 'SELECT VERSION() AS version;';
  list($mysql_version) = mysql_fetch_array(pwg_query($query));
  if (count($datas) < 10 or version_compare($mysql_version, '4.0.4') < 0)
  {
    // MySQL is prior to version 4.0.4, multi table update feature is not
    // available
    foreach ($datas as $data)
    {
      $query = '
UPDATE '.$tablename.'
  SET ';
      $is_first = true;
      foreach ($dbfields['update'] as $num => $key)
      {
        if (!$is_first)
        {
          $query.= ",\n      ";
        }
        $query.= $key.' = ';
        if (isset($data[$key]) and $data[$key] != '')
        {
          $query.= '\''.$data[$key].'\'';
        }
        else
        {
          $query.= 'NULL';
        }
        $is_first = false;
      }
      $query.= '
  WHERE ';
      foreach ($dbfields['primary'] as $num => $key)
      {
        if ($num > 1)
        {
          $query.= ' AND ';
        }
        $query.= $key.' = \''.$data[$key].'\'';
      }
      $query.= '
;';
      pwg_query($query);
    }
  }
  else
  {
    // creation of the temporary table
    $query = '
DESCRIBE '.$tablename.'
;';
    $result = pwg_query($query);
    $columns = array();
    $all_fields = array_merge($dbfields['primary'], $dbfields['update']);
    while ($row = mysql_fetch_array($result))
    {
      if (in_array($row['Field'], $all_fields))
      {
        $column = $row['Field'];
        $column.= ' '.$row['Type'];
        if (!isset($row['Null']) or $row['Null'] == '')
        {
          $column.= ' NOT NULL';
        }
        if (isset($row['Default']))
        {
          $column.= " default '".$row['Default']."'";
        }
        array_push($columns, $column);
      }
    }

    $temporary_tablename = $tablename.'_'.micro_seconds();

    $query = '
CREATE TABLE '.$temporary_tablename.'
(
'.implode(",\n", $columns).',
PRIMARY KEY ('.implode(',', $dbfields['primary']).')
)
;';
    pwg_query($query);
    mass_inserts($temporary_tablename, $all_fields, $datas);
    // update of images table by joining with temporary table
    $query = '
UPDATE '.$tablename.' AS t1, '.$temporary_tablename.' AS t2
  SET '.implode("\n    , ",
                array_map(
                  create_function('$s', 'return "t1.$s = t2.$s";')
                  , $dbfields['update'])).'
  WHERE '.implode("\n    AND ",
                array_map(
                  create_function('$s', 'return "t1.$s = t2.$s";')
                  , $dbfields['primary'])).'
;';
    pwg_query($query);
    $query = '
DROP TABLE '.$temporary_tablename.'
;';
    pwg_query($query);
  }
}

/**
 * updates the global_rank of categories under the given id_uppercat
 *
 * @param int id_uppercat
 * @return void
 */
function update_global_rank($id_uppercat = 'all')
{
  $query = '
SELECT id,rank
  FROM '.CATEGORIES_TABLE.'
;';
  $result = pwg_query($query);
  $ranks_array = array();
  while ($row = mysql_fetch_array($result))
  {
    $ranks_array[$row['id']] = $row['rank'];
  }

  // which categories to update ?
  $uppercats_array = array();

  $query = '
SELECT id,uppercats
  FROM '.CATEGORIES_TABLE;
  if (is_numeric($id_uppercat))
  {
    $query.= '
  WHERE uppercats REGEXP \'(^|,)'.$id_uppercat.'(,|$)\'
    AND id != '.$id_uppercat.'
';
  }
  $query.= '
;';
  $result = pwg_query($query);
  while ($row = mysql_fetch_array($result))
  {
    $uppercats_array[$row['id']] =  $row['uppercats'];
  }

  $datas = array();
  foreach ($uppercats_array as $id => $uppercats)
  {
    $data = array();
    $data['id'] = $id;
    $global_rank = preg_replace('/(\d+)/e',
                                "\$ranks_array['$1']",
                                str_replace(',', '.', $uppercats));
    $data['global_rank'] = $global_rank;
    array_push($datas, $data);
  }

  $fields = array('primary' => array('id'), 'update' => array('global_rank'));
  mass_updates(CATEGORIES_TABLE, $fields, $datas);
}

/**
 * change the visible property on a set of categories
 *
 * @param array categories
 * @param string value
 * @return void
 */
function set_cat_visible($categories, $value)
{
  if (!in_array($value, array('true', 'false')))
  {
    return false;
  }

  // unlocking a category => all its parent categories become unlocked
  if ($value == 'true')
  {
    $uppercats = get_uppercat_ids($categories);
    $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET visible = \'true\'
  WHERE id IN ('.implode(',', $uppercats).')
;';
    pwg_query($query);
  }
  // locking a category   => all its child categories become locked
  if ($value == 'false')
  {
    $subcats = get_subcat_ids($categories);
    $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET visible = \'false\'
  WHERE id IN ('.implode(',', $subcats).')
;';
    pwg_query($query);
  }
}

/**
 * change the status property on a set of categories : private or public
 *
 * @param array categories
 * @param string value
 * @return void
 */
function set_cat_status($categories, $value)
{
  if (!in_array($value, array('public', 'private')))
  {
    return false;
  }

  // make public a category => all its parent categories become public
  if ($value == 'public')
  {
    $uppercats = get_uppercat_ids($categories);
    $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET status = \'public\'
  WHERE id IN ('.implode(',', $uppercats).')
;';
    pwg_query($query);
  }
  // make a category private => all its child categories become private
  if ($value == 'private')
  {
    $subcats = get_subcat_ids($categories);
    $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET status = \'private\'
  WHERE id IN ('.implode(',', $subcats).')
;';
    pwg_query($query);
  }
}

/**
 * returns all uppercats category ids of the given category ids
 *
 * @param array cat_ids
 * @return array
 */
function get_uppercat_ids($cat_ids)
{
  if (!is_array($cat_ids) or count($cat_ids) < 1)
  {
    return array();
  }

  $uppercats = array();

  $query = '
SELECT uppercats
  FROM '.CATEGORIES_TABLE.'
  WHERE id IN ('.implode(',', $cat_ids).')
;';
  $result = pwg_query($query);
  while ($row = mysql_fetch_array($result))
  {
    $uppercats = array_merge($uppercats,
                             explode(',', $row['uppercats']));
  }
  $uppercats = array_unique($uppercats);

  return $uppercats;
}

/**
 * set a new random representant to the categories
 *
 * @param array categories
 */
function set_random_representant($categories)
{
  $datas = array();
  foreach ($categories as $category_id)
  {
    $query = '
SELECT image_id
  FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE category_id = '.$category_id.'
  ORDER BY RAND()
  LIMIT 0,1
;';
    list($representative) = mysql_fetch_array(pwg_query($query));
    $data = array('id' => $category_id,
                  'representative_picture_id' => $representative);
    array_push($datas, $data);
  }

  $fields = array('primary' => array('id'),
                  'update' => array('representative_picture_id'));
  mass_updates(CATEGORIES_TABLE, $fields, $datas);
}

/**
 * order categories (update categories.rank and global_rank database fields)
 *
 * the purpose of this function is to give a rank for all categories
 * (insides its sub-category), even the newer that have none at te
 * beginning. For this, ordering function selects all categories ordered by
 * rank ASC then name ASC for each uppercat.
 *
 * @returns void
 */
function ordering()
{
  $current_rank = 0;
  $current_uppercat = '';

  $query = '
SELECT id, if(id_uppercat is null,\'\',id_uppercat) AS id_uppercat
  FROM '.CATEGORIES_TABLE.'
  ORDER BY id_uppercat,rank,name
;';
  $result = pwg_query($query);
  $datas = array();
  while ($row = mysql_fetch_array($result))
  {
    if ($row['id_uppercat'] != $current_uppercat)
    {
      $current_rank = 0;
      $current_uppercat = $row['id_uppercat'];
    }
    $data = array('id' => $row['id'], 'rank' => ++$current_rank);
    array_push($datas, $data);
  }

  $fields = array('primary' => array('id'), 'update' => array('rank'));
  mass_updates(CATEGORIES_TABLE, $fields, $datas);
}

/**
 * returns the fulldir for each given category id
 *
 * @param array cat_ids
 * @return array
 */
function get_fulldirs($cat_ids)
{
  if (count($cat_ids) == 0)
  {
    return array();
  }

  // caching directories of existing categories
  $query = '
SELECT id, dir
  FROM '.CATEGORIES_TABLE.'
  WHERE dir IS NOT NULL
;';
  $result = pwg_query($query);
  $cat_dirs = array();
  while ($row = mysql_fetch_array($result))
  {
    $cat_dirs[$row['id']] = $row['dir'];
  }

  // caching galleries_url
  $query = '
SELECT id, galleries_url
  FROM '.SITES_TABLE.'
;';
  $result = pwg_query($query);
  $galleries_url = array();
  while ($row = mysql_fetch_array($result))
  {
    $galleries_url[$row['id']] = $row['galleries_url'];
  }

  // categories : id, site_id, uppercats
  $categories = array();

  $query = '
SELECT id, uppercats, site_id
  FROM '.CATEGORIES_TABLE.'
  WHERE id IN (
'.wordwrap(implode(', ', $cat_ids), 80, "\n").')
;';
  $result = pwg_query($query);
  while ($row = mysql_fetch_array($result))
  {
    array_push($categories, $row);
  }

  // filling $cat_fulldirs
  $cat_fulldirs = array();
  foreach ($categories as $category)
  {
    $uppercats = str_replace(',', '/', $category['uppercats']);
    $cat_fulldirs[$category['id']] = $galleries_url[$category['site_id']];
    $cat_fulldirs[$category['id']].= preg_replace('/(\d+)/e',
                                                  "\$cat_dirs['$1']",
                                                  $uppercats);
  }

  return $cat_fulldirs;
}

/**
 * returns an array with all file system files according to
 * $conf['file_ext']
 *
 * @param string $path
 * @param bool recursive
 * @return array
 */
function get_fs($path, $recursive = true)
{
  global $conf;

  // because isset is faster than in_array...
  if (!isset($conf['flip_picture_ext']))
  {
    $conf['flip_picture_ext'] = array_flip($conf['picture_ext']);
  }
  if (!isset($conf['flip_file_ext']))
  {
    $conf['flip_file_ext'] = array_flip($conf['file_ext']);
  }

  $fs['elements'] = array();
  $fs['thumbnails'] = array();
  $fs['representatives'] = array();
  $subdirs = array();

  if (is_dir($path))
  {
    if ($contents = opendir($path))
    {
      while (($node = readdir($contents)) !== false)
      {
        if (is_file($path.'/'.$node))
        {
          $extension = get_extension($node);

//          if (in_array($extension, $conf['picture_ext']))
          if (isset($conf['flip_picture_ext'][$extension]))
          {
            if (basename($path) == 'thumbnail')
            {
              array_push($fs['thumbnails'], $path.'/'.$node);
            }
            else if (basename($path) == 'pwg_representative')
            {
              array_push($fs['representatives'], $path.'/'.$node);
            }
            else
            {
              array_push($fs['elements'], $path.'/'.$node);
            }
          }
//          else if (in_array($extension, $conf['file_ext']))
          else if (isset($conf['flip_file_ext'][$extension]))
          {
            array_push($fs['elements'], $path.'/'.$node);
          }
        }
        else if (is_dir($path.'/'.$node)
                 and $node != '.'
                 and $node != '..'
                 and $node != 'pwg_high'
                 and $recursive)
        {
          array_push($subdirs, $node);
        }
      }
    }
    closedir($contents);

    foreach ($subdirs as $subdir)
    {
      $tmp_fs = get_fs($path.'/'.$subdir);

      $fs['elements']        = array_merge($fs['elements'],
                                           $tmp_fs['elements']);

      $fs['thumbnails']      = array_merge($fs['thumbnails'],
                                           $tmp_fs['thumbnails']);

      $fs['representatives'] = array_merge($fs['representatives'],
                                           $tmp_fs['representatives']);
    }
  }
  return $fs;
}

/**
 * stupidly returns the current microsecond since Unix epoch
 */
function micro_seconds()
{
  $t1 = explode(' ', microtime());
  $t2 = explode('.', $t1[0]);
  $t2 = $t1[1].substr($t2[1], 0, 6);
  return $t2;
}

/**
 * synchronize base users list and related users list
 *
 * compares and synchronizes base users table (USERS_TABLE) with its child
 * tables (USER_INFOS_TABLE, USER_ACCESS, USER_CACHE, USER_GROUP) : each
 * base user must be present in child tables, users in child tables not
 * present in base table must be deleted.
 *
 * @return void
 */
function sync_users()
{
  global $conf;

  $query = '
SELECT '.$conf['user_fields']['id'].' AS id
  FROM '.USERS_TABLE.'
;';
  $base_users = array_from_query($query, 'id');

  $query = '
SELECT user_id
  FROM '.USER_INFOS_TABLE.'
;';
  $infos_users = array_from_query($query, 'user_id');

  // users present in $base_users and not in $infos_users must be added
  $to_create = array_diff($base_users, $infos_users);

  if (count($to_create) > 0)
  {
    $inserts = array();

    list($dbnow) = mysql_fetch_row(pwg_query('SELECT NOW();'));

    foreach ($to_create as $user_id)
    {
      $insert = array();
      $insert['user_id'] = $user_id;
      $insert['status'] = 'guest';
      $insert['template'] = $conf['default_template'];
      $insert['nb_image_line'] = $conf['nb_image_line'];
      $insert['nb_line_page'] = $conf['nb_line_page'];
      $insert['language'] = $conf['default_language'];
      $insert['recent_period'] = $conf['recent_period'];
      $insert['expand'] = boolean_to_string($conf['auto_expand']);
      $insert['show_nb_comments'] =
        boolean_to_string($conf['show_nb_comments']);
      $insert['maxwidth'] = $conf['default_maxwidth'];
      $insert['maxheight'] = $conf['default_maxheight'];
      $insert['registration_date'] = $dbnow;

      array_push($inserts, $insert);
    }

    mass_inserts(USER_INFOS_TABLE,
                 array_keys($inserts[0]),
                 $inserts);
  }

  // users present in user related tables must be present in the base user
  // table
  $tables =
    array(
      USER_MAIL_NOTIFICATION_TABLE,
      USER_FEED_TABLE,
      USER_INFOS_TABLE,
      USER_ACCESS_TABLE,
      USER_CACHE_TABLE,
      USER_GROUP_TABLE
      );
  foreach ($tables as $table)
  {
    $query = '
SELECT user_id
  FROM '.$table.'
;';
    $to_delete =
      array_diff(
        array_from_query($query, 'user_id'),
        $base_users
        );

    if (count($to_delete) > 0)
    {
      $query = '
DELETE
  FROM '.$table.'
  WHERE user_id in ('.implode(',', $to_delete).')
;';
      pwg_query($query);
    }
  }
}

/**
 * updates categories.uppercats field based on categories.id +
 * categories.id_uppercat
 *
 * @return void
 */
function update_uppercats()
{
  $uppercat_ids = array();

  $query = '
SELECT id, id_uppercat
  FROM '.CATEGORIES_TABLE.'
;';
  $result = pwg_query($query);
  while ($row = mysql_fetch_array($result))
  {
    $uppercat_ids[$row['id']] =
      !empty($row['id_uppercat']) ? $row['id_uppercat'] : 'NULL';
  }

  // uppercats array associates a category id to the list of uppercats id.
  $uppercats = array();

  foreach (array_keys($uppercat_ids) as $id)
  {
    $uppercats[$id] = array();

    $uppercat = $id;

    while ($uppercat != 'NULL')
    {
      array_push($uppercats[$id], $uppercat);
      $uppercat = $uppercat_ids[$uppercat];
    }
  }

  $datas = array();

  foreach ($uppercats as $id => $list)
  {
    array_push(
      $datas,
      array(
        'id' => $id,
        'uppercats' => implode(',', array_reverse($list))
        )
      );
  }

  $fields = array('primary' => array('id'), 'update' => array('uppercats'));
  mass_updates(CATEGORIES_TABLE, $fields, $datas);
}

/**
 * update images.path field
 *
 * @return void
 */
function update_path()
{
  $images_of = array();
  
  $query = '
SELECT category_id, image_id
  FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE is_storage = \'true\'
;';
  $result = pwg_query($query);
  while ($row = mysql_fetch_array($result))
  {
    if (!isset($images_of[ $row['category_id'] ]))
    {
      $images_of[ $row['category_id'] ] = array();
    }

    array_push(
      $images_of[ $row['category_id'] ],
      $row['image_id']
      );
  }
  
  $fulldirs = get_fulldirs(
    array_keys($images_of)
    );

  foreach ($images_of as $cat_id => $image_ids)
  {
    $query = '
UPDATE '.IMAGES_TABLE.'
  SET path = CONCAT(\''.$fulldirs[$cat_id].'\',\'/\',file)
  WHERE id IN ('.
      wordwrap(
        implode(', ', $image_ids),
        80,
        "\n").
      ')
;';
    pwg_query($query);
  }
}

/**
 * update images.average_rate field
 * param int $element_id optional, otherwise applies to all
 * @return void
 */
function update_average_rate( $element_id=-1 )
{
  $query = '
SELECT element_id,
       ROUND(AVG(rate),2) AS average_rate
  FROM '.RATE_TABLE;
  if ( $element_id != -1 )
  {
    $query .= ' WHERE element_id=' . $element_id;
  }
  $query .= ' GROUP BY element_id;';

  $result = pwg_query($query);

  $datas = array();

  while ($row = mysql_fetch_array($result))
  {
    array_push(
      $datas,
      array(
        'id' => $row['element_id'],
        'average_rate' => $row['average_rate']
        )
      );
  }

  mass_updates(
    IMAGES_TABLE,
    array(
      'primary' => array('id'),
      'update' => array('average_rate')
      ),
    $datas
    );

  $query='
SELECT id FROM '.IMAGES_TABLE .'
  LEFT JOIN '.RATE_TABLE.' ON id=element_id
  WHERE element_id IS NULL AND average_rate IS NOT NULL';
  if ( $element_id != -1 )
  {
    $query .= ' AND id=' . $element_id;
  }
  $to_update = array_from_query( $query, 'id');

  if ( !empty($to_update) )
  {
    $query='
UPDATE '.IMAGES_TABLE .'
  SET average_rate=NULL
  WHERE id IN (' . implode(',',$to_update) . ')';
    pwg_query($query);
  }
}

/**
 * change the parent category of the given categories. The categories are
 * supposed virtual.
 *
 * @param array category identifiers
 * @param int parent category identifier
 * @return void
 */
function move_categories($category_ids, $new_parent = -1)
{
  global $page;

  if (count($category_ids) == 0)
  {
    return;
  }

  $new_parent = $new_parent < 1 ? 'NULL' : $new_parent;

  $categories = array();

  $query = '
SELECT id, id_uppercat, status, uppercats
  FROM '.CATEGORIES_TABLE.'
  WHERE id IN ('.implode(',', $category_ids).')
;';
  $result = pwg_query($query);
  while ($row = mysql_fetch_array($result))
  {
    $categories[$row['id']] =
      array(
        'parent' => empty($row['id_uppercat']) ? 'NULL' : $row['id_uppercat'],
        'status' => $row['status'],
        'uppercats' => $row['uppercats']
        );
  }

  // is the movement possible? The movement is impossible if you try to move
  // a category in a sub-category or itself
  if ('NULL' != $new_parent)
  {
    $query = '
SELECT uppercats
  FROM '.CATEGORIES_TABLE.'
  WHERE id = '.$new_parent.'
;';
    list($new_parent_uppercats) = mysql_fetch_row(pwg_query($query));

    foreach ($categories as $category)
    {
      // technically, you can't move a category with uppercats 12,125,13,14
      // into a new parent category with uppercats 12,125,13,14,24
      if (preg_match('/^'.$category['uppercats'].'/', $new_parent_uppercats))
      {
        array_push(
          $page['errors'],
          l10n('You cannot move a category in its own sub category')
          );
        return;
      }
    }
  }

  $tables =
    array(
      USER_ACCESS_TABLE => 'user_id',
      GROUP_ACCESS_TABLE => 'group_id'
      );

  $query = '
UPDATE '.CATEGORIES_TABLE.'
  SET id_uppercat = '.$new_parent.'
  WHERE id IN ('.implode(',', $category_ids).')
;';
  pwg_query($query);

  update_uppercats();
  ordering();
  update_global_rank();

  // status and related permissions management
  if ('NULL' == $new_parent)
  {
    $parent_status = 'public';
  }
  else
  {
    $query = '
SELECT status
  FROM '.CATEGORIES_TABLE.'
  WHERE id = '.$new_parent.'
;';
    list($parent_status) = mysql_fetch_row(pwg_query($query));
  }

  if ('private' == $parent_status)
  {
    foreach ($categories as $cat_id => $category)
    {
      switch ($category['status'])
      {
        case 'public' :
        {
          set_cat_status(array($cat_id), 'private');
          break;
        }
        case 'private' :
        {
          $subcats = get_subcat_ids(array($cat_id));

          foreach ($tables as $table => $field)
          {
            $query = '
SELECT '.$field.'
  FROM '.$table.'
  WHERE cat_id = '.$cat_id.'
;';
            $category_access = array_from_query($query, $field);

            $query = '
SELECT '.$field.'
  FROM '.$table.'
  WHERE cat_id = '.$new_parent.'
;';
            $parent_access = array_from_query($query, $field);

            $to_delete = array_diff($parent_access, $category_access);

            if (count($to_delete) > 0)
            {
              $query = '
DELETE FROM '.$table.'
  WHERE '.$field.' IN ('.implode(',', $to_delete).')
    AND cat_id IN ('.implode(',', $subcats).')
;';
              pwg_query($query);
            }
          }
          break;
        }
      }
    }
  }

  array_push(
    $page['infos'],
    sprintf(
      l10n('%d categories moved'),
      count($categories)
      )
    );
}

/**
 * Returns all destinations of a list of source categories. This function
 * solves transitivity.
 *
 * @param mixed array of category ids, empty for all categories
 */
function get_destinations($categories = 'all')
{
  $query = '
SELECT source, destination
  FROM '.CATEGORIES_LINK_TABLE.'
';
  $result = pwg_query($query);

  $destinations_of = array();
  
  while ($row = mysql_fetch_array($result))
  {
    if (!isset($destinations_of[ $row['source'] ]))
    {
      $destinations_of[ $row['source'] ] = array();
    }

    array_push(
      $destinations_of[ $row['source'] ],
      $row['destination']
      );
  }

  // transitivity resolution: if " => " means "source of", if A=>B=>C
  // implies A=>B and A=>C. So A has 2 destinations: B and C.
  do
  {
    // let's suppose we only need a single turn
    $need_new_turn = false;
    
    foreach ($destinations_of as $source => $destinations)
    {
      foreach ($destinations as $destination)
      {
        // does the current destination has destinations itself?
        if (isset($destinations_of[$destination]))
        {
          // are there destinations of current destination not already among
          // destinations of the current source? (advise: take a piece of
          // paper and draw a schema). The source itself must not be counted
          // as a destination, thus avoiding cyclic links.
          $missing_destinations = array_diff(
            $destinations_of[$destination],
            $destinations,
            array($source) // no cyclic link
            );
          
          if (count($missing_destinations) > 0)
          {
            $destinations_of[$source] = array_unique(
              array_merge(
                $destinations,
                $missing_destinations
                )
              );

            // a category has a least one new destination, we have to check
            // one more time that it doesn't generate more destinations
            $need_new_turn = true;
          }
        }
      }
    }
  } while ($need_new_turn);

  if (is_array($categories))
  {
    $filtered_destinations_of = array();

    // Even if there is no destinations for the requested categories, we
    // return empty arrays
    foreach ($categories as $category)
    {
      $filtered_destinations_of[$category] = array();
    }
    
    foreach ($destinations_of as $source => $destinations)
    {
      if (in_array($source, $categories))
      {
        $filtered_destinations_of[$source] = $destinations;
      }
    }

    return $filtered_destinations_of;
  }
  else
  {
    return $destinations_of;
  }
}

/**
 * Returns all sources of a list of destination categories. This function
 * solves transitivity.
 *
 * @param mixed array of category ids, empty for all categories
 */
function get_sources($categories = 'all')
{
  $destinations_of = get_destinations();

  $sources_of = array();
  
  foreach ($destinations_of as $source => $destinations)
  {
    foreach ($destinations as $destination)
    {
      if (!isset($sources_of[$destination]))
      {
        $sources_of[$destination] = array();
      }

      array_push($sources_of[$destination], $source);
    }
  }
  
  // eventually, filter
  if (is_array($categories))
  {
    $filtered_sources_of = array();

    // Even if there is no sources for the requested categories, we return
    // empty arrays
    foreach ($categories as $category)
    {
      $filtered_sources_of[$category] = array();
    }
    
    foreach ($sources_of as $destination => $sources)
    {
      if (in_array($destination, $categories))
      {
        $filtered_sources_of[$destination] = $sources;
      }
    }

    return $filtered_sources_of;
  }
  else
  {
    return $sources_of;
  }
}

/**
 * Checks categories links are respected for a given list of destinations.
 *
 * Checking categories links means that each destination must be associated
 * to the images of its sources.
 *
 * @param mixed source category ids
 */
function check_links($destinations = 'all')
{
  $sources_of = get_sources($destinations);

  if (empty($sources_of))
  {
    return true;
  }

  // we need to search images of all sources and destinations
  $images_of = array();

  foreach ($sources_of as $destination => $sources)
  {
    $images_of[$destination] = array();

    foreach ($sources as $source)
    {
      $images_of[$source] = array();
    }
  }
  
  $query = '
SELECT image_id, category_id
  FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE category_id IN ('.
    implode(',', array_keys($images_of)).
    ')
;';
  $result = pwg_query($query);

  while ($row = mysql_fetch_array($result))
  {
    array_push(
      $images_of[ $row['category_id'] ],
      $row['image_id']
      );
  }

  $inserts = array();
  
  foreach ($sources_of as $destination => $sources)
  {
    // merge all images from the sources of this destination
    $sources_images = array();
    
    foreach ($sources as $source)
    {
      $sources_images = array_merge(
        $sources_images,
        $images_of[$source]
        );
    }

    $sources_images = array_unique($sources_images);

    // are there images among the sources that are not linked to the
    // destination?
    $missing_images = array_diff(
      $sources_images,
      $images_of[$destination]
      );

    // if we find missing images (missing links in reality), we prepare the
    // final mass_inserts
    if (count($missing_images) > 0)
    {
      foreach ($missing_images as $missing_image)
      {
        array_push(
          $inserts,
          array(
            'category_id' => $destination,
            'image_id'    => $missing_image,
            )
          );
      }
    }
  }

  if (count($inserts) > 0)
  {
    mass_inserts(
      IMAGE_CATEGORY_TABLE,
      array_keys($inserts[0]),
      $inserts
      );
  }
}

/**
 * Based on categories links, delete image_category links on destinations.
 *
 * The rule is the following: if an image belong to the category and to the
 * source, we suppose it comes from the source. If the source/destination
 * link is broken, we delete the image/category link if the only origin of
 * the link was the broken categories link.
 *
 * Example: "=>" means "source of". Between brackets the associated images.
 *
 * A (1,2,9) => \
 *               |=> C (1,2,3,4,5,9) => D (1,2,3,4,5,6,9)
 * B (3,4,9) => /
 *
 * In category C, we suppose (1,2) come from A, (3,4) from B, 9 from A or B
 * and 5 was manually added. In category D, 6 was added manually.
 *
 * If we break A=>C, C and D loose (1,2) but not 9 because it can come from
 * B. If we break C=>D, D loose (3,4,5,9) but not 6 because it was
 * associated manually to 9.
 *
 * Warning: only virtual links can be removed, physical links are protected.
 * 
 * @param int destination
 * @param array sources
 */
function delete_sources($destination, $sources)
{
  // if no sources to unlink, we stop with OK status
  if (count($sources) == 0)
  {
    return true;
  }

  $query = '
DELETE
  FROM '.CATEGORIES_LINK_TABLE.'
  WHERE destination = '.$destination.'
    AND source IN ('.implode(',', $sources).')
;';
  pwg_query($query);
  
  // The strategy is the following:
  //
  // * first we brutally delete the image/category associations on
  // destinations categories for all images belonging to sources.
  //
  // * then we check_links on destinations to rebuild missing image/category
  // associations.

  // what are the images associated to the sources to unlink
  $query = '
SELECT image_id
  FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE category_id IN ('.
    implode(',', $sources).
    ')
;';
  $sources_images = array_unique(
    array_from_query($query, 'image_id')
    );

  if (count($sources_images) == 0)
  {
    return true;
  }

  // retrieve all direct and indirect destinations of the current
  // destination
  $destinations_of = get_destinations(array($destination));

  $destinations = array_merge(
    array($destination),
    $destinations_of[$destination]
    );
  
  // unlink sources images from destinations
  $query = '
DELETE
  FROM '.IMAGE_CATEGORY_TABLE.'
  WHERE category_id IN ('.implode(',', $destinations).')
    AND image_id IN ('.implode(',', $sources_images).')
    AND is_storage = \'false\'
;';
  pwg_query($query);

  // if the representative thumbnail of destinations was a picture from
  // $sources_images, we request a new random representant
  $query = '
SELECT id, representative_picture_id
  FROM '.CATEGORIES_TABLE.'
  WHERE id IN ('.implode(',', $destinations).')
;';
  $result = pwg_query($query);

  $request_random = array();
  
  while ($row = mysql_fetch_array($result))
  {
    if (isset($row['representative_picture_id']))
    {
      if (in_array($row['representative_picture_id'], $sources_images))
      {
        array_push($request_random, $row['id']);
      }
    }
  }

  set_random_representant($request_random);

  // eventually, we check_links to rebuild missing associations
  check_links($destinations);

  return true;
}

/**
 * create a virtual category
 *
 * @param string category name
 * @param int parent category id
 * @return array with ('info' and 'id') or ('error') key
 */
function create_virtual_category($category_name, $parent_id=null)
{
  global $conf;
  
  // is the given category name only containing blank spaces ?
  if (preg_match('/^\s*$/', $category_name))
  {
    return array('error' => l10n('cat_error_name'));
  }
        
  $parent_id = !empty($parent_id) ? $parent_id : 'NULL';

  $query = '
SELECT MAX(rank)
  FROM '.CATEGORIES_TABLE.'
  WHERE id_uppercat '.(is_numeric($parent_id) ? '= '.$parent_id : 'IS NULL').'
;';
  list($current_rank) = mysql_fetch_array(pwg_query($query));
  
  $insert = array(
    'name' => $category_name,
    'rank' => ++$current_rank,
    'commentable' => $conf['newcat_default_commentable'],
    'uploadable' => 'false',
    );
    
  if ($parent_id != 'NULL')
  {
    $query = '
SELECT id, uppercats, global_rank, visible, status
  FROM '.CATEGORIES_TABLE.'
  WHERE id = '.$parent_id.'
;';
    $parent = mysql_fetch_array(pwg_query($query));

    $insert{'id_uppercat'} = $parent{'id'};
    $insert{'global_rank'} = $parent{'global_rank'}.'.'.$insert{'rank'};
    
    // at creation, must a category be visible or not ? Warning : if the
    // parent category is invisible, the category is automatically create
    // invisible. (invisible = locked)
    if ('false' == $parent['visible'])
    {
      $insert{'visible'} = 'false';
    }
    else
    {
      $insert{'visible'} = $conf['newcat_default_visible'];
    }
    
    // at creation, must a category be public or private ? Warning : if the
    // parent category is private, the category is automatically create
    // private.
    if ('private' == $parent['status'])
    {
      $insert{'status'} = 'private';
    }
    else
    {
      $insert{'status'} = $conf['newcat_default_status'];
    }
  }
  else
  {
    $insert{'visible'} = $conf['newcat_default_visible'];
    $insert{'status'} = $conf['newcat_default_status'];
    $insert{'global_rank'} = $insert{'rank'};
  }

  // we have then to add the virtual category
  mass_inserts(
    CATEGORIES_TABLE,
    array(
      'site_id', 'name', 'id_uppercat', 'rank', 'commentable',
      'uploadable', 'visible', 'status', 'global_rank',
      ),
    array($insert)
    );

  $inserted_id = mysql_insert_id();

  $query = '
UPDATE
  '.CATEGORIES_TABLE.'
  SET uppercats = \''.
    (isset($parent) ? $parent{'uppercats'}.',' : '').
    $inserted_id.
    '\'
  WHERE id = '.$inserted_id.'
;';
  pwg_query($query);
  
  return array(
    'info' => l10n('cat_virtual_added'),
    'id'   => $inserted_id,
    );
}
?>