Merge of the 1.3.1 release

Creation of an unique include file (common.php)
Creation of an unique define file (include/constants.php)
Modification of the installation procedure


git-svn-id: http://piwigo.org/svn/trunk@345 68402e56-0260-453c-a942-63ccdbb3a9ee

21 files changed, 1721 insertions, 775 deletions

diff --git a/admin.php b/admin.php
index 5105d9ea3..5707cca0f 100644
--- a/admin.php
+++ b/admin.php
@@ -17,7 +17,9 @@
  *                                                                         *
  ***************************************************************************/
 
-//----------------------------------------------------------- personnal include
+//----------------------------------------------------------- include
+$phpwg_root_path = './';
+include_once( $phpwg_root_path.'common.php' );
 include_once( './admin/include/isadmin.inc.php' );
 //----------------------------------------------------- template initialization
 $vtp = new VTemplate;
@@ -34,6 +36,7 @@ if ( is_file( './install.php' ) )
 //--------------------------------------- validating page and creation of title
 $page_valide = false;
 $title = '';
+if (isset( $_GET['page'] ))
 switch ( $_GET['page'] )
 {
  case 'user_list':
diff --git a/admin/cat_list.php b/admin/cat_list.php
index 706dce2ac..9c6af62dd 100644
--- a/admin/cat_list.php
+++ b/admin/cat_list.php
@@ -18,18 +18,41 @@
  *                                                                         *
  ***************************************************************************/
 include_once( './admin/include/isadmin.inc.php' );
+
 //----------------------------------------------------- template initialization
 $sub = $vtp->Open( './template/'.$user['template'].'/admin/cat_list.vtp' );
 $tpl = array( 'cat_edit','cat_up','cat_down','cat_image_info',
               'cat_permission','cat_update','cat_add','cat_parent','submit',
-              'cat_virtual','delete','cat_first','cat_last' );
+              'cat_virtual','delete','cat_first','cat_last','errors_title' );
 templatize_array( $tpl, 'lang', $sub );
 $vtp->setGlobalVar( $sub, 'user_template', $user['template'] );
 //--------------------------------------------------- adding a virtual category
 $errors = array();
 if ( isset( $_POST['submit'] ) )
 {
-  if ( !preg_match( '/^\s*$/', $_POST['virtual_name'] ) )
+  // is the given category name only containing blank spaces ?
+  if ( preg_match( '/^\s*$/', $_POST['virtual_name'] ) )
+    array_push( $errors, $lang['cat_error_name'] );
+  // does the uppercat id exists in the database ?
+  if ( $_POST['associate'] == '' )
+  {
+    $_POST['associate'] = -1;
+  }
+  else if ( !is_numeric( $_POST['associate'] ) )
+  {
+    array_push( $errors, $lang['cat_unknown_id'] );
+  }
+  else
+  {
+    $query = 'SELECT id';
+    $query.= ' FROM '.PREFIX_TABLE.'categories';
+    $query.= ' WHERE id = '.$_POST['associate'];
+    $query.= ';';
+    if ( mysql_num_rows( mysql_query( $query ) ) == 0 )
+      array_push( $errors, $lang['cat_unknown_id'] );
+  }
+  
+  if ( count( $errors ) == 0 )
   {
     // we have then to add the virtual category
     $query = 'INSERT INTO '.PREFIX_TABLE.'categories';
@@ -41,10 +64,7 @@ if ( isset( $_POST['submit'] ) )
     $query.= " ('".$_POST['virtual_name']."',".$_POST['associate'].")";
     $query.= ';';
     mysql_query( $query );
-  }
-  else
-  {
-    array_push( $errors, $lang['cat_error_name'] );
+    synchronize_all_users();
   }
 }
 //---------------------------------------------------------------  rank updates
@@ -171,6 +191,7 @@ if ( isset( $_GET['first'] ) and is_numeric( $_GET['first'] ) )
 if ( isset( $_GET['delete'] ) and is_numeric( $_GET['delete'] ) )
 {
   delete_category( $_GET['delete'] );
+  synchronize_all_users();
 }
 //------------------------------------------------------------------ reordering
 function ordering( $id_uppercat )
@@ -233,6 +254,8 @@ function display_cat_manager( $id_uppercat, $indent,
   $query.= ';';
   $result = mysql_query( $query );
   $row    = mysql_fetch_array( $result );
+  if ( !isset( $row['min'] ) ) $row['min'] = 0;
+  if ( !isset( $row['max'] ) ) $row['max'] = 0;
   $min_rank = $row['min'];
   $max_rank = $row['max'];
 		
@@ -258,13 +281,39 @@ function display_cat_manager( $id_uppercat, $indent,
   while ( $row = mysql_fetch_array( $result ) )
   {
     $subcat_visible = true;
+    if ( !isset( $row['dir'] ) ) $row['dir'] = '';
 
     $vtp->addSession( $sub, 'cat' );
+    // is the category expanded or not ?
+    if ( isset($page['expand']) && $page['expand'] == 'all' )
+    {
+      $vtp->addSession( $sub, 'bullet_wo_link' );
+      $vtp->closeSession( $sub, 'bullet_wo_link' );
+    }
+    else if ( isset($page['tab_expand']) && in_array( $row['id'], $page['tab_expand'] ) )
+    {
+      $vtp->addSession( $sub, 'bullet_expanded' );
+      $tab_expand = array_diff( $page['tab_expand'], array( $row['id'] ) );
+      $expand = implode( ',', $tab_expand );
+      $url = './admin.php?page=cat_list&expand='.$expand;
+      $vtp->setVar( $sub, 'bullet_expanded.link', add_session_id( $url ) );
+      $vtp->closeSession( $sub, 'bullet_expanded' );
+    }
+    else
+    {
+      $vtp->addSession( $sub, 'bullet_collapsed' );
+      $tab_expand = array_merge( $page['tab_expand'], array( $row['id'] ) );
+      $expand = implode( ',', $tab_expand );
+      $url = './admin.php?page=cat_list&expand='.$expand;
+      $vtp->setVar( $sub, 'bullet_collapsed.link', add_session_id( $url ) );
+      $vtp->closeSession( $sub, 'bullet_collapsed' );
+    }
+    
     $vtp->setVar( $sub, 'cat.td', $td );
     $vtp->setVar( $sub, 'cat.class', $class );
     $vtp->setVar( $sub, 'cat.indent', $indent );
     $vtp->setVar( $sub, 'cat.name', $row['name'] );
-    $vtp->setVar( $sub, 'cat.id', $row['id'] );
+
     if ( $row['dir'] != '' )
     {
       $vtp->addSession( $sub, 'storage' );
@@ -280,7 +329,8 @@ function display_cat_manager( $id_uppercat, $indent,
       $vtp->closeSession( $sub, 'virtual' );
       // category can be deleted
       $vtp->addSession( $sub, 'delete' );
-      $url = './admin.php?page=cat_list&delete='.$row['id'];
+      $url = './admin.php?page=cat_list&expand='.$page['expand'];
+      $url.= '&delete='.$row['id'];
       $vtp->setVar( $sub, 'delete.delete_url', add_session_id( $url ) );
       $vtp->closeSession( $sub, 'delete' );
     }
@@ -299,41 +349,40 @@ function display_cat_manager( $id_uppercat, $indent,
     if ( $row['rank'] != $min_rank )
     {
       $vtp->addSession( $sub, 'up' );
-      $vtp->setVar( $sub, 'up.id', $row['id'] );
-      $url = add_session_id( './admin.php?page=cat_list&up='.$row['id'] );
-      $vtp->setVar( $sub, 'up.up_url', $url );
+      $url = './admin.php?page=cat_list&expand='.$page['expand'];
+      $url.= '&up='.$row['id'];
+      $vtp->setVar( $sub, 'up.up_url', add_session_id( $url ) );
       $vtp->closeSession( $sub, 'up' );
     }
     else if ( $min_rank != $max_rank )
     {
       $vtp->addSession( $sub, 'no_up' );
-      $vtp->setVar( $sub, 'no_up.id', $row['id'] );
-      $url = add_session_id( './admin.php?page=cat_list&last='.$row['id']);
-      $vtp->setVar( $sub, 'no_up.last_url', $url );
+      $url = './admin.php?page=cat_list&expand='.$page['expand'];
+      $url.= '&last='.$row['id'];
+      $vtp->setVar( $sub, 'no_up.last_url', add_session_id( $url ) );
       $vtp->closeSession( $sub, 'no_up' );
     }
     if ( $row['rank'] != $max_rank )
     {
       $vtp->addSession( $sub, 'down' );
-      $vtp->setVar( $sub, 'down.id', $row['id'] );
-      $url = add_session_id( './admin.php?page=cat_list&down='.$row['id']);
-      $vtp->setVar( $sub, 'down.down_url', $url );
+      $url = './admin.php?page=cat_list&expand='.$page['expand'];
+      $url.= '&down='.$row['id'];
+      $vtp->setVar( $sub, 'down.down_url', add_session_id( $url ) );
       $vtp->closeSession( $sub, 'down' );
     }
     else if ( $min_rank != $max_rank )
     {
       $vtp->addSession( $sub, 'no_down' );
-      $vtp->setVar( $sub, 'no_down.id', $row['id'] );
-      $url = add_session_id('./admin.php?page=cat_list&first='.$row['id']);
-      $vtp->setVar( $sub, 'no_down.first_url', $url );
+      $url = './admin.php?page=cat_list&expand='.$page['expand'];
+      $url.= '&first='.$row['id'];
+      $vtp->setVar( $sub, 'no_down.first_url', add_session_id( $url ) );
       $vtp->closeSession( $sub, 'no_down' );
     }
     if ( $row['nb_images'] > 0 )
     {
       $vtp->addSession( $sub, 'image_info' );
-      $url = add_session_id( './admin.php?page=infos_images&cat_id='
-                             .$row['id'] );
-      $vtp->setVar( $sub, 'image_info.image_info_url', $url );
+      $url = './admin.php?page=infos_images&cat_id='.$row['id'];
+      $vtp->setVar( $sub, 'image_info.image_info_url', add_session_id($url) );
       $vtp->closeSession( $sub, 'image_info' );
     }
     else
@@ -371,19 +420,39 @@ function display_cat_manager( $id_uppercat, $indent,
 
     $vtp->closeSession( $sub, 'cat' );
 
-    display_cat_manager( $row['id'], $indent.str_repeat( '&nbsp', 4 ),
-                         $subcat_visible, $level + 1 );
+    if ( in_array( $row['id'], $page['tab_expand'] )
+         or $page['expand'] == 'all')
+      display_cat_manager( $row['id'], $indent.str_repeat( '&nbsp', 4 ),
+                           $subcat_visible, $level + 1 );
   }
 }
 display_cat_manager( 'NULL', str_repeat( '&nbsp', 4 ), true, 0 );
 // add a virtual category ?
-$vtp->addSession( $sub, 'associate_cat' );
-$vtp->setVar( $sub, 'associate_cat.value', '-1' );
-$vtp->setVar( $sub, 'associate_cat.content', '' );
-$vtp->closeSession( $sub, 'associate_cat' );
-$page['plain_structure'] = get_plain_structure();
-$structure = create_structure( '', array() );
-display_categories( $structure, ' ' );
+// We only show a List Of Values if the number of categories is less than
+// $conf['max_LOV_categories']
+$query = 'SELECT COUNT(id) AS nb_total_categories';
+$query.= ' FROM '.PREFIX_TABLE.'categories';
+$query.= ';';
+$row = mysql_fetch_array( mysql_query( $query ) );
+if ( $row['nb_total_categories'] < $conf['max_LOV_categories'] )
+{
+  $vtp->addSession( $sub, 'associate_LOV' );
+  $vtp->addSession( $sub, 'associate_cat' );
+  $vtp->setVar( $sub, 'associate_cat.value', '-1' );
+  $vtp->setVar( $sub, 'associate_cat.content', '' );
+  $vtp->closeSession( $sub, 'associate_cat' );
+  $page['plain_structure'] = get_plain_structure( true );
+  $structure = create_structure( '', array() );
+  display_categories( $structure, '&nbsp;' );
+  $vtp->closeSession( $sub, 'associate_LOV' );
+}
+// else, we only display a small text field, we suppose the administrator
+// knows the id of its category
+else
+{
+  $vtp->addSession( $sub, 'associate_text' );
+  $vtp->closeSession( $sub, 'associate_text' );
+}
 //----------------------------------------------------------- sending html code
 $vtp->Parse( $handle , 'sub', $sub );
 ?>
\ No newline at end of file
diff --git a/admin/cat_modify.php b/admin/cat_modify.php
index ad0911a0c..50741feea 100644
--- a/admin/cat_modify.php
+++ b/admin/cat_modify.php
@@ -40,20 +40,6 @@ if ( isset( $_POST['submit'] ) )
   $query.= ' WHERE id = '.$_GET['cat'];
   $query.= ';';
   $row = mysql_fetch_array( mysql_query( $query ) );
-
-  if ( $_POST['status'] != $row['status'] )
-  {
-    // deletion of all access for groups concerning this category
-    $query = 'DELETE';
-    $query.= ' FROM '.PREFIX_TABLE.'group_access';
-    $query.= ' WHERE cat_id = '.$_GET['cat'];
-    mysql_query( $query );
-    // deletion of all access for users concerning this category
-    $query = 'DELETE';
-    $query.= ' FROM '.PREFIX_TABLE.'user_access';
-    $query.= ' WHERE cat_id = '.$_GET['cat'];
-    mysql_query( $query );
-  }
   
   $query = 'UPDATE '.PREFIX_TABLE.'categories';
 
@@ -78,13 +64,31 @@ if ( isset( $_POST['submit'] ) )
   if ( isset( $_POST['associate'] ) )
   {
     $query.= ', id_uppercat = ';
-    if ( $_POST['associate'] == -1 ) $query.= 'NULL';
-    else                             $query.= $_POST['associate'];
+    if ( $_POST['associate'] == -1 or $_POST['associate'] == '' )
+      $query.= 'NULL';
+    else
+      $query.= $_POST['associate'];
   }
   $query.= ' WHERE id = '.$_GET['cat'];
   $query.= ';';
   mysql_query( $query );
 
+  if ( $_POST['status'] != $row['status'] )
+  {
+    // deletion of all access for groups concerning this category
+    $query = 'DELETE';
+    $query.= ' FROM '.PREFIX_TABLE.'group_access';
+    $query.= ' WHERE cat_id = '.$_GET['cat'];
+    mysql_query( $query );
+    // deletion of all access for users concerning this category
+    $query = 'DELETE';
+    $query.= ' FROM '.PREFIX_TABLE.'user_access';
+    $query.= ' WHERE cat_id = '.$_GET['cat'];
+    mysql_query( $query );
+    // resynchronize all users
+    synchronize_all_users();
+  }
+
   // checking users favorites
   $query = 'SELECT id';
   $query.= ' FROM '.PREFIX_TABLE.'users';
@@ -111,6 +115,10 @@ $query.= ' WHERE a.id = '.$_GET['cat'];
 $query.= ' AND a.site_id = b.id';
 $query.= ';';
 $row = mysql_fetch_array( mysql_query( $query ) );
+
+if ( !isset( $row['dir'] ) ) $row['dir'] = '';
+if ( !isset( $row['id_uppercat'] ) ) $row['id_uppercat'] = '';
+
 $result = get_cat_info( $row['id'] );
 // cat name
 $cat_name = get_cat_display_name( $result['name'], ' - ', '' );
@@ -135,6 +143,7 @@ if ( $row['site_id'] != 1 )
   $vtp->closeSession( $sub, 'server' );
 }
 $vtp->setVar( $sub, 'name',    $row['name'] );
+if ( !isset( $row['comment'] ) ) $row['comment'] = '';
 $vtp->setVar( $sub, 'comment', $row['comment'] );
 // status : public, private...
 $options = get_enums( PREFIX_TABLE.'categories', 'status' );
@@ -203,12 +212,32 @@ if ( $conf['upload_available'] and $row['dir'] != '' and $row['site_id'] == 1 )
 if ( $row['dir'] == '' )
 {
   $vtp->addSession( $sub, 'parent' );
-  $vtp->addSession( $sub, 'associate_cat' );
-  $vtp->setVar( $sub, 'associate_cat.value', '-1' );
-  $vtp->setVar( $sub, 'associate_cat.content', '' );
-  $vtp->closeSession( $sub, 'associate_cat' );
-  $structure = create_structure( '', array() );
-  display_categories( $structure, '&nbsp;', $row['id_uppercat'], $row['id'] );
+  // We only show a List Of Values if the number of categories is less than
+  // $conf['max_LOV_categories']
+  $query = 'SELECT COUNT(id) AS nb_total_categories';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= ';';
+  $countrow = mysql_fetch_array( mysql_query( $query ) );
+  if ( $countrow['nb_total_categories'] < $conf['max_LOV_categories'] )
+  {
+    $vtp->addSession( $sub, 'associate_LOV' );
+    $vtp->addSession( $sub, 'associate_cat' );
+    $vtp->setVar( $sub, 'associate_cat.value', '-1' );
+    $vtp->setVar( $sub, 'associate_cat.content', '' );
+    $vtp->closeSession( $sub, 'associate_cat' );
+    $page['plain_structure'] = get_plain_structure( true );
+    $structure = create_structure( '', array() );
+    display_categories( $structure, '&nbsp;', $row['id_uppercat'],$row['id'] );
+    $vtp->closeSession( $sub, 'associate_LOV' );
+  }
+  // else, we only display a small text field, we suppose the administrator
+  // knows the id of its category
+  else
+  {
+    $vtp->addSession( $sub, 'associate_text' );
+    $vtp->setVar( $sub, 'associate_text.value', $row['id_uppercat'] );
+    $vtp->closeSession( $sub, 'associate_text' );
+  }
   $vtp->closeSession( $sub, 'parent' );
 }
 //----------------------------------------------------------- sending html code
diff --git a/admin/cat_perm.php b/admin/cat_perm.php
index 81d9f9945..09767c19b 100644
--- a/admin/cat_perm.php
+++ b/admin/cat_perm.php
@@ -83,6 +83,8 @@ if ( isset( $_POST['submit'] ) )
     }
     check_favorites( $row['id'] );
   }
+  // resynchronize all users
+  synchronize_all_users();
 }
 //---------------------------------------------------------------------- groups
 $query = 'SELECT id,name';
@@ -149,7 +151,7 @@ while ( $row = mysql_fetch_array( $result ) )
 
   // for color of user : (red means access forbidden, green authorized) we
   // ask all forbidden categories, including the groups rights
-  $restrictions = get_restrictions( $row['id'], $row['status'], false );
+  $restrictions = get_user_restrictions( $row['id'], $row['status'], false );
   $is_user_allowed = is_user_allowed( $page['cat'], $restrictions );
   if ( $is_user_allowed == 0 )
   {
@@ -161,7 +163,7 @@ while ( $row = mysql_fetch_array( $result ) )
   }
   // for permission update button, we only ask forbidden categories for the
   // user, not taking into account the groups the user belongs to
-  $restrictions = get_restrictions( $row['id'], $row['status'], false, false );
+  $restrictions = get_user_restrictions($row['id'],$row['status'],false,false);
   $is_user_allowed = is_user_allowed( $page['cat'], $restrictions );
   if ( $is_user_allowed == 2 )
   {
diff --git a/admin/comments.php b/admin/comments.php
index 1b23fbbff..8d7c3122e 100644
--- a/admin/comments.php
+++ b/admin/comments.php
@@ -36,7 +36,7 @@ function display_pictures( $mysql_result, $maxtime, $validation_box = false )
     $subresult = mysql_query( $query );
     $subrow = mysql_fetch_array( $subresult );
 
-    if ( $array_cat_directories[$subrow['cat_id']] == '' )
+    if ( !isset( $array_cat_directories[$subrow['cat_id']] ) )
     {
       $array_cat_directories[$subrow['cat_id']] =
         get_complete_dir( $subrow['cat_id'] );
@@ -49,7 +49,7 @@ function display_pictures( $mysql_result, $maxtime, $validation_box = false )
     $file = get_filename_wo_extension( $subrow['file'] );
     // name of the picture
     $name = $array_cat_names[$subrow['cat_id']].' &gt; ';
-    if ( $subrow['name'] != '' )
+    if ( isset( $subrow['name'] ) and $subrow['name'] != '' )
     {
       $name.= $subrow['name'];
     }
@@ -159,8 +159,8 @@ $tpl = array( 'stats_last_days','delete','close','submit','open' );
 templatize_array( $tpl, 'lang', $sub );
 $vtp->setGlobalVar( $sub, 'user_template', $user['template'] );
 //--------------------------------------------------- number of days to display
-if ( isset( $_GET['last_days'] ) ) define( "MAX_DAYS", $_GET['last_days'] );
-else                               define( "MAX_DAYS", 0 );
+if ( isset( $_GET['last_days'] ) ) define( 'MAX_DAYS', $_GET['last_days'] );
+else                               define( 'MAX_DAYS', 0 );
 //----------------------------------------- non specific section initialization
 $array_cat_directories = array();
 $array_cat_names       = array();
diff --git a/admin/configuration.php b/admin/configuration.php
index bced7704f..9f4bbca97 100644
--- a/admin/configuration.php
+++ b/admin/configuration.php
@@ -60,6 +60,7 @@ if ( isset( $_POST['submit'] ) )
     mysql_query( $query );
   }
   // deletion of site as asked
+  $site_deleted = false;
   $query = 'SELECT id';
   $query.= ' FROM '.PREFIX_TABLE.'sites';
   $query.= " WHERE galleries_url <> './galleries/';";
@@ -70,12 +71,17 @@ if ( isset( $_POST['submit'] ) )
     if ( $_POST[$site] == 1 )
     {
       delete_site( $row['id'] );
-      // if any picture of this site were linked to another categories, we
-      // have to update the informations of those categories. To make it
-      // simple, we just update all the categories
-      update_category( 'all' );
+      $site_deleted = true;
     }
   }
+  // if any picture of this site were linked to another categories, we have
+  // to update the informations of those categories. To make it simple, we
+  // just update all the categories
+  if ( $site_deleted )
+  {
+    update_category( 'all' );
+    synchronize_all_users();
+  }
   // thumbnail prefix must not contain accentuated characters
   $old_prefix = $_POST['prefix_thumbnail'];
   $prefix = strtr( $_POST['prefix_thumbnail'], $Caracs );
@@ -234,30 +240,22 @@ if ( isset( $_POST['submit'] ) )
 else
 {
 //--------------------------------------------------------- data initialization
-  $query  = 'SELECT';
-  foreach ( $conf_infos as $i => $conf_info ) {
-    if ( $i > 0 ) $query.= ',';
-    else          $query.= ' ';
-    $query.= $conf_info;
-  }
+  $query  = 'SELECT '.implode( ',', $conf_infos );
   $query .= ' FROM '.PREFIX_TABLE.'config;';
   $row = mysql_fetch_array( mysql_query( $query ) );
-  foreach ( $conf_infos as $conf_info ) {
-    $$conf_info = $row[$conf_info];
+  foreach ( $conf_infos as $info ) {
+    if ( isset( $row[$info] ) ) $$info = $row[$info];
+    else                        $$info = '';
   }
 
-  $query  = 'SELECT';
-  foreach ( $default_user_infos as $i => $default_user_info ) {
-    if ( $i > 0 ) $query.= ',';
-    else          $query.= ' ';
-    $query.= $default_user_info;
-  }
+  $query  = 'SELECT '.implode( ',', $default_user_infos );
   $query.= ' FROM '.PREFIX_TABLE.'users';
   $query.= " WHERE username = 'guest'";
   $query.= ';';
   $row = mysql_fetch_array( mysql_query( $query ) );
-  foreach ( $default_user_infos as $default_user_info ) {
-    $$default_user_info = $row[$default_user_info];
+  foreach ( $default_user_infos as $info ) {
+    if ( isset( $row[$info] ) ) $$info = $row[$info];
+    else                        $$info = '';
   }
 }
 //----------------------------------------------------- template initialization
@@ -653,6 +651,7 @@ $vtp->setVar( $sub, 'param_line.name', $lang['customize_theme'] );
 $vtp->addSession( $sub, 'select' );
 $vtp->setVar( $sub, 'select.name', 'template' );
 $option = get_dirs( './template/' );
+
 for ( $i = 0; $i < sizeof( $option ); $i++ )
 {
   $vtp->addSession( $sub, 'option' );
diff --git a/admin/create_listing_file.php b/admin/create_listing_file.php
index 507a4862f..c4f880424 100644
--- a/admin/create_listing_file.php
+++ b/admin/create_listing_file.php
@@ -9,8 +9,7 @@
  *                                                                         *
  ***************************************************************************/
 
-$prefix_thumbnail = 'TN-';
-	
+$conf['prefix_thumbnail'] = 'TN-';
 $conf['picture_ext'] = array ( 'jpg', 'gif', 'png', 'JPG', 'GIF', 'PNG' );
 
 $listing = '';
@@ -20,24 +19,76 @@ $local_folder = substr( $_SERVER['PHP_SELF'], 0, $end );
 $url = 'http://'.$_SERVER['HTTP_HOST'].$local_folder;
 
 $listing.= '<url>'.$url.'</url>';
-	
+
+/**
+ * returns an array with all picture files according to $conf['picture_ext']
+ *
+ * @param string $dir
+ * @return array
+ */
+function get_picture_files( $dir )
+{
+  global $conf;
+
+  $pictures = array();
+  if ( $opendir = opendir( $dir ) )
+  {
+    while ( $file = readdir( $opendir ) )
+    {
+      if ( in_array( get_extension( $file ), $conf['picture_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 ) )
+  {
+    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;
+}
+
 // get_dirs retourne un tableau contenant tous les sous-répertoires d'un
 // répertoire
-function get_dirs( $rep, $indent, $level )
+function get_dirs( $basedir, $indent, $level )
 {
-  $sub_rep = array();
-  $i = 0;
+  $fs_dirs = array();
   $dirs = "";
-  if ( $opendir = opendir ( $rep ) )
+
+  if ( $opendir = opendir( $basedir ) )
   {
-    while ( $file = readdir ( $opendir ) )
+    while ( $file = readdir( $opendir ) )
     {
-      if ( $file != "."
-           and $file != ".."
-           and is_dir ( $rep."/".$file )
-           and $file != "thumbnail" )
+      if ( $file != '.'
+           and $file != '..'
+           and is_dir ( $basedir.'/'.$file )
+           and $file != 'thumbnail' )
       {
-        $sub_rep[$i++] = $file;
+        array_push( $fs_dirs, $file );
         if ( !preg_match( '/^[a-zA-Z0-9-_.]+$/', $file ) )
         {
           echo '<span style="color:red;">"'.$file.'" : ';
@@ -49,11 +100,10 @@ function get_dirs( $rep, $indent, $level )
     }
   }
   // write of the dirs
-  for ( $i = 0; $i < sizeof( $sub_rep ); $i++ )
-  {
-    $dirs.= "\n".$indent.'<dir'.$level.' name="'.$sub_rep[$i].'">';
-    $dirs.= get_pictures( $rep.'/'.$sub_rep[$i], $indent.'  ' );
-    $dirs.= get_dirs( $rep.'/'.$sub_rep[$i], $indent.'  ', $level + 1 );
+  foreach ( $fs_dirs as $fs_dir ) {
+    $dirs.= "\n".$indent.'<dir'.$level.' name="'.$fs_dir.'">';
+    $dirs.= get_pictures( $basedir.'/'.$fs_dir, $indent.'  ' );
+    $dirs.= get_dirs( $basedir.'/'.$fs_dir, $indent.'  ', $level + 1 );
     $dirs.= "\n".$indent.'</dir'.$level.'>';
   }
   return $dirs;		
@@ -73,101 +123,60 @@ function get_filename_wo_extension( $filename )
   return substr( $filename, 0, strrpos( $filename, '.' ) );
 }
 
-function is_image( $filename )
+function get_pictures( $dir, $indent )
 {
   global $conf;
-
-  if ( !is_dir( $filename )
-       and in_array( get_extension( $filename ), $conf['picture_ext'] ) )
-  {
-    return true;
-  }
-  return false;
-}
-
-function TN_exists( $dir, $file )
-{
-  global $conf, $prefix_thumbnail;
-
-  $titre = get_filename_wo_extension( $file );
-
-  for ( $i = 0; $i < sizeof ( $conf['picture_ext'] ); $i++ )
-  {
-    $base_tn_name = $dir.'/thumbnail/'.$prefix_thumbnail.$titre.'.';
-    $ext = $conf['picture_ext'][$i];
-    if ( is_file( $base_tn_name.$ext ) )
-    {
-      return $ext;
+  
+  // fs means filesystem : $fs_pictures contains pictures in the filesystem
+  // found in $dir, $fs_thumbnails contains thumbnails...
+  $fs_pictures   = get_picture_files( $dir );
+  $fs_thumbnails = get_thumb_files( $dir.'/thumbnail' );
+
+  $root = "\n".$indent.'<root>';
+
+  foreach ( $fs_pictures as $fs_picture ) {
+    $file_wo_ext = get_filename_wo_extension( $fs_picture );
+    $tn_ext = '';
+    foreach ( $conf['picture_ext'] as $ext ) {
+      $test = $conf['prefix_thumbnail'].$file_wo_ext.'.'.$ext;
+      if ( !in_array( $test, $fs_thumbnails ) ) continue;
+      else { $tn_ext = $ext; break; }
     }
-  }
-  echo 'The thumbnail is missing for '.$dir.'/'.$file;
-  echo '-> '.$dir.'/thumbnail/'.$prefix_thumbnail.$titre.'.xxx';
-  echo ' ("xxx" can be : ';
-  for ( $i = 0; $i < sizeof ( $conf['picture_ext'] ); $i++ )
-  {
-    if ( $i > 0 )
+    // if we found a thumnbnail corresponding to our picture...
+    if ( $tn_ext != '' )
     {
-      echo ', ';
-    }
-    echo '"'.$conf['picture_ext'][$i].'"';
-  }
-  echo ')<br />';
-  return false;
-}
+      list( $width,$height ) = @getimagesize( $dir.'/'.$fs_picture );
 
-function get_pictures( $rep, $indent )
-{
-  $pictures = array();		
-
-  $tn_ext = '';
-  $root = '';
-  if ( $opendir = opendir ( $rep ) )
-  {
-    while ( $file = readdir ( $opendir ) )
-    {
-      if ( is_image( $file ) and $tn_ext = TN_exists( $rep, $file ) )
+      $root.= "\n".$indent.'  ';
+      $root.= '<picture';
+      $root.= ' file="'.    $fs_picture.'"';
+      $root.= ' tn_ext="'.  $tn_ext.'"';
+      $root.= ' filesize="'.floor(filesize($dir.'/'.$fs_picture)/1024).'"';
+      $root.= ' width="'.   $width.'"';
+      $root.= ' height="'.  $height.'"';
+      $root.= ' />';
+      
+      if ( !preg_match( '/^[a-zA-Z0-9-_.]+$/', $fs_picture ) )
       {
-        $picture = array();
-
-        $picture['file']     = $file;
-        $picture['tn_ext']   = $tn_ext;
-        $picture['date']     = date('Y-m-d',filemtime( $rep.'/'.$file ) );
-        $picture['filesize'] = floor( filesize( $rep."/".$file ) / 1024 );
-        $image_size = @getimagesize( $rep."/".$file );
-        $picture['width']    = $image_size[0];
-        $picture['height']   = $image_size[1];
-
-        array_push( $pictures, $picture );
-
-        if ( !preg_match( '/^[a-zA-Z0-9-_.]+$/', $file ) )
-        {
-          echo '<span style="color:red;">"'.$file.'" : ';
-          echo 'The name of the picture should be composed of ';
-          echo 'letters, figures, "-", "_" or "." ONLY';
-          echo '</span><br />';
-        }
+        echo '<span style="color:red;">"'.$fs_picture.'" : ';
+        echo 'The name of the picture should be composed of ';
+        echo 'letters, figures, "-", "_" or "." ONLY';
+        echo '</span><br />';
       }
     }
-  }
-  // write of the node <root> with all the pictures at the root of the
-  // directory
-  $root.= "\n".$indent."<root>";
-  if ( sizeof( $pictures ) > 0 )
-  {
-    for( $i = 0; $i < sizeof( $pictures ); $i++ )
+    else
     {
-      $root.= "\n".$indent.'  ';
-      $root.= '<picture';
-      $root.= ' file="'.     $pictures[$i]['file'].     '"';
-      $root.= ' tn_ext="'.   $pictures[$i]['tn_ext'].   '"';
-      $root.= ' date="'.     $pictures[$i]['date'].     '"';
-      $root.= ' filesize="'. $pictures[$i]['filesize']. '"';
-      $root.= ' width="'.    $pictures[$i]['width'].    '"';
-      $root.= ' height="'.   $pictures[$i]['height'].   '"';
-      $root.= ' />';
+      echo 'The thumbnail is missing for '.$dir.'/'.$fs_picture;
+      echo '-> '.$dir.'/thumbnail/';
+      echo $conf['prefix_thumbnail'].$file_wo_ext.'.xxx';
+      echo ' ("xxx" can be : ';
+      echo implode( ', ', $conf['picture_ext'] );
+      echo ')<br />';
     }
   }
+
   $root.= "\n".$indent.'</root>';
+
   return $root;
 }
 
@@ -177,11 +186,10 @@ if ( $fp = @fopen("./listing.xml","w") )
 {
   fwrite( $fp, $listing );
   fclose( $fp );
+  echo "listing.xml created";
 }
 else
 {
   echo "I can't write the file listing.xml";
 }
-
-echo "listing.xml created";
 ?>
\ No newline at end of file
diff --git a/admin/group_list.php b/admin/group_list.php
index 871df6a6a..aac5b41bc 100644
--- a/admin/group_list.php
+++ b/admin/group_list.php
@@ -33,7 +33,7 @@ if ( isset ( $_GET['delete'] ) and is_numeric( $_GET['delete'] ) )
   $query.= ';';
   $row = mysql_fetch_array( mysql_query( $query ) );
   // confirm group deletion ?
-  if ( $_GET['confirm'] != 1 )
+  if ( !isset( $_GET['confirm'] ) or $_GET['confirm'] != 1 )
   {
     $vtp->addSession( $sub, 'deletion' );
     $vtp->setVar( $sub, 'deletion.name', $row['name'] );
diff --git a/admin/group_perm.php b/admin/group_perm.php
index 85d92a65b..53ed7fd81 100644
--- a/admin/group_perm.php
+++ b/admin/group_perm.php
@@ -60,6 +60,8 @@ if ( isset( $_POST['submit'] ) )
   {
     check_favorites( $row['id'] );
   }
+  // synchronization of calculated data
+  synchronize_group( $_GET['group_id'] );
   // confirmation display
   $vtp->addSession( $sub, 'confirmation' );
   $url = './admin.php?page=group_list';
diff --git a/admin/include/functions.php b/admin/include/functions.php
index f29b469d6..ce7fa076f 100644
--- a/admin/include/functions.php
+++ b/admin/include/functions.php
@@ -53,7 +53,59 @@ function is_image( $filename, $create_thumbnail = false )
   }
   return false;
 }
-	
+
+/**
+ * returns an array with all picture files according to $conf['picture_ext']
+ *
+ * @param string $dir
+ * @return array
+ */
+function get_picture_files( $dir )
+{
+  global $conf;
+
+  $pictures = array();
+  if ( $opendir = opendir( $dir ) )
+  {
+    while ( $file = readdir( $opendir ) )
+    {
+      if ( in_array( get_extension( $file ), $conf['picture_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 ) )
+  {
+    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;
+}
+
 function TN_exists( $dir, $file )
 {
   global $conf;
@@ -67,8 +119,9 @@ function TN_exists( $dir, $file )
     }
   }
   return false;
-}	
+}
 	
+
 // The function delete_site deletes a site
 // and call the function delete_category for each primary category of the site
 function delete_site( $id )
@@ -91,6 +144,7 @@ function delete_site( $id )
   mysql_query( $query );
 }
 	
+
 // The function delete_category deletes the category identified by the $id
 // It also deletes (in the database) :
 //    - all the images of the images (thanks to delete_image, see further)
@@ -144,6 +198,7 @@ function delete_category( $id )
   mysql_query( $query );
 }
 	
+
 // The function delete_image deletes the image identified by the $id
 // It also deletes (in the database) :
 //    - all the comments related to the image
@@ -178,13 +233,14 @@ function delete_image( $id )
   mysql_query( $query );
   $count_deleted++;
 }
-	
+
 // 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
 //     - all sessions linked to this user
+//     - all categories informations linked to this user
 function delete_user( $user_id )
 {
   // destruction of the access linked to the user
@@ -210,7 +266,13 @@ function delete_user( $user_id )
   $query.= ' WHERE user_id = '.$user_id;
   $query.= ';';
   mysql_query( $query );
-		
+
+  // destruction of the categories informations linked with the user
+  $query = 'DELETE FROM '.PREFIX_TABLE.'user_category';
+  $query.= ' WHERE user_id = '.$user_id;
+  $query.= ';';
+  mysql_query( $query );
+
   // destruction of the user
   $query = 'DELETE FROM '.PREFIX_TABLE.'users';
   $query.= ' WHERE id = '.$user_id;
@@ -230,7 +292,10 @@ function delete_group( $group_id )
   $query.= ';';
   mysql_query( $query );
 
-  // destruction of the group links for this group
+  // synchronize all users linked to the group
+  synchronize_group( $group_id );
+
+  // destruction of the users links for this group
   $query = 'DELETE FROM '.PREFIX_TABLE.'user_group';
   $query.= ' WHERE group_id = '.$group_id;
   $query.= ';';
@@ -248,14 +313,17 @@ function delete_group( $group_id )
 // or invisible)
 function check_favorites( $user_id )
 {
-  $query = 'SELECT status';
+  $query = 'SELECT status,forbidden_categories';
   $query.= ' FROM '.PREFIX_TABLE.'users';
   $query.= ' WHERE id = '.$user_id;
   $query.= ';';
   $row = mysql_fetch_array( mysql_query( $query ) );
   $status = $row['status'];
   // retrieving all the restricted categories for this user
-  $restricted_cat = get_all_restrictions( $user_id, $status );
+  if ( isset( $row['forbidden_categories'] ) )
+    $restricted_cat = explode( ',', $row['forbidden_categories'] );
+  else
+    $restricted_cat = array();
   // retrieving all the favorites for this user and comparing their
   // categories to the restricted categories
   $query = 'SELECT image_id';
@@ -314,26 +382,22 @@ function update_category( $id = 'all' )
     $query.= ' FROM '.PREFIX_TABLE.'image_category';
     $query.= ' WHERE category_id = '.$id;
     $query.= ';';
-    $row = mysql_fetch_array( mysql_query( $query ) );
-    $query = 'UPDATE '.PREFIX_TABLE.'categories';
-    $query.= ' SET nb_images = '.$row['nb_images'];
-    $query.= ' WHERE id = '.$id;
-    $query.= ';';
-    mysql_query( $query );
+    list( $nb_images ) = mysql_fetch_array( mysql_query( $query ) );
     // updating the date_last
-    $query = 'SELECT date_available';
+    $query = 'SELECT MAX(date_available) AS date_available';
     $query.= ' FROM '.PREFIX_TABLE.'images';
-    $query.= ' LEFT JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
+    $query.= ' INNER JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
     $query.= ' WHERE category_id = '.$id;
-    $query.= ' ORDER BY date_available DESC';
-    $query.= ' LIMIT 0,1';
     $query.= ';';
-    $row = mysql_fetch_array( mysql_query( $query ) );
+    list( $date_available ) = mysql_fetch_array( mysql_query( $query ) );
+    
     $query = 'UPDATE '.PREFIX_TABLE.'categories';
-    $query.= " SET date_last = '".$row['date_available']."'";
+    $query.= " SET date_last = '".$date_available."'";
+    $query.= ', nb_images = '.$nb_images;
     $query.= ' WHERE id = '.$id;
     $query.= ';';
     mysql_query( $query );
+
     // updating the representative_picture_id : if the representative
     // picture of the category is not any more linked to the category, we
     // have to set representative_picture_id to NULL
@@ -343,7 +407,7 @@ function update_category( $id = 'all' )
     $row = mysql_fetch_array( mysql_query( $query ) );
     // if the category has no representative picture (ie
     // representative_picture_id == NULL) we don't update anything
-    if ( $row['representative_picture_id'] != '' )
+    if ( isset( $row['representative_picture_id'] ) )
     {
       $query = 'SELECT image_id';
       $query.= ' FROM '.PREFIX_TABLE.'image_category';
@@ -366,7 +430,7 @@ function update_category( $id = 'all' )
 function check_date_format( $date )
 {
   // date arrives at this format : DD/MM/YYYY
-  list($day,$month,$year) = explode( '/', $date );
+  @list($day,$month,$year) = explode( '/', $date );
   return @checkdate( $month, $day, $year );
 }
 
@@ -432,4 +496,518 @@ function display_categories( $categories, $indent,
     }
   }
 }
-?>
\ No newline at end of file
+
+/**
+ * Complete plain structure of the gallery
+ *
+ * Returns the plain structure (one level array) of the gallery. In the
+ * returned array, each element is an array with jeys 'id' and
+ * 'id_uppercat'. The function also fills the array $page['subcats'] which
+ * associate (category_id => array of sub-categories id).
+ *
+ * @param bool $use_name
+ * @return array
+ */
+function get_plain_structure( $use_name = false )
+{
+  global $page;
+
+  $plain_structure = array();
+
+  $query = 'SELECT id,id_uppercat';
+  if ( $use_name ) $query.= ',name';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= ' ORDER BY id_uppercat ASC, rank ASC';
+  $query.= ';';
+
+  $subcats = array();
+  $id_uppercat = 'NULL';
+
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    $plain_structure[$row['id']]['id'] = $row['id'];
+    if ( !isset( $row['id_uppercat'] ) ) $row['id_uppercat'] = 'NULL';
+    $plain_structure[$row['id']]['id_uppercat'] = $row['id_uppercat'];
+    if ( $use_name ) $plain_structure[$row['id']]['name'] = $row['name'];
+    // subcats list
+    if ( $row['id_uppercat'] != $id_uppercat )
+    {
+      $page['subcats'][$id_uppercat] = $subcats;
+
+      $subcats = array();
+      $id_uppercat = $row['id_uppercat'];
+    }
+    array_push( $subcats, $row['id'] );
+  }
+  mysql_free_result( $result );
+  
+  $page['subcats'][$id_uppercat] = $subcats;
+
+  return $plain_structure;
+}
+
+/**
+ * get N levels array representing structure under the given category
+ *
+ * create_structure returns the N levels array representing structure under
+ * the given gategory id. It also updates the
+ * $page['plain_structure'][id]['all_subcats_id'] and
+ * $page['plain_structure'][id]['direct_subcats_ids'] for each sub category.
+ *
+ * @param int $id_uppercat
+ * @return array
+ */
+function create_structure( $id_uppercat )
+{
+  global $page;
+
+  $structure = array();
+  $ids = get_subcats_ids( $id_uppercat );
+  foreach ( $ids as $id ) {
+    $category = $page['plain_structure'][$id];
+
+    $category['subcats'] = create_structure( $id );
+
+    $page['plain_structure'][$id]['all_subcats_ids'] =
+      get_all_subcats_ids( $id );
+
+    $page['plain_structure'][$id]['direct_subcats_ids'] =
+      get_subcats_ids( $id );
+
+    array_push( $structure, $category );
+  }
+  return $structure;
+}
+
+/**
+ * returns direct sub-categories ids
+ *
+ * Returns an array containing all the direct sub-categories ids of the
+ * given category. It uses the $page['subcats'] global array.
+ *
+ * @param int $id_uppercat
+ * @return array
+ */
+function get_subcats_ids( $id_uppercat )
+{
+  global $page;
+
+  if ( $id_uppercat == '' ) $id_uppercat = 'NULL';
+
+  if ( isset( $page['subcats'][$id_uppercat] ) )
+    return $page['subcats'][$id_uppercat];
+  else
+    return array();
+}
+
+/**
+ * returns all sub-categories ids, not only direct ones
+ *
+ * Returns an array containing all the sub-categories ids of the given
+ * category, not only direct ones. This function is recursive.
+ *
+ * @param int $category_id
+ * @return array
+ */
+function get_all_subcats_ids( $category_id )
+{
+  $ids = array();
+  
+  $subcats = get_subcats_ids( $category_id );
+  $ids = array_merge( $ids, $subcats );
+  foreach ( $subcats as $subcat ) {
+    // recursive call
+    $sub_subcats = get_all_subcats_ids( $subcat );
+    $ids = array_merge( $ids, $sub_subcats );
+  }
+  return array_unique( $ids );
+}
+
+/**
+ * prepares the query to update the table user_category
+ *
+ * Prepares the query (global variable $values) to update table
+ * user_category : for a couple (user,category) the number of sub-categories
+ * and the last date of the category (all sub-categories taken into
+ * account). It also calls function update_uppercats for each category. The
+ * function is recursive.
+ *
+ * @param array $categories
+ * @return void
+ */
+function update_user_category( $categories )
+{
+  global $page,$user_restrictions,$value_num,$values;
+
+  foreach ( $categories as $category ) {
+    // recursive call
+    update_user_category( $category['subcats'] );
+    // 1. update the table user_category
+    foreach ( $user_restrictions as $user_id => $restrictions ) {
+      // if the category is forbidden to this user, go to next user
+      if ( in_array( $category['id'], $restrictions ) ) continue;
+
+      // how many sub_categories for this user ?
+      $user_subcats = array_diff(
+        $page['plain_structure'][$category['id']]['direct_subcats_ids'],
+        $restrictions );
+      $user_nb_subcats = count( array_unique( $user_subcats ) );
+      // last date of the category
+      $user_all_subcats = array_unique( array_diff(
+        $page['plain_structure'][$category['id']]['all_subcats_ids'],
+        $restrictions ) );
+            
+      $query = 'SELECT MAX(date_last) AS last_date';
+      $query.= ' FROM '.PREFIX_TABLE.'categories';
+      $query.= ' WHERE id IN ('.$category['id'];
+      if ( count( $user_all_subcats ) > 0 )
+        $query.= ','.implode( ',', $user_all_subcats );
+      $query.= ')';
+      $query.= ';';
+      $row = mysql_fetch_array( mysql_query( $query ) );
+
+      // insert a new line in database
+      if ( $value_num++ > 0 ) $values.= ', ';
+      else                    $values.= ' ';
+      $values.= '('.$user_id.",".$category['id'];
+      if ( isset( $row['last_date'] ) ) $values.= ",'".$row['last_date']."'";
+      else                              $values.= ',NULL';
+      $values.= ','.$user_nb_subcats.')';
+    }
+    update_uppercats( $category['id'] );
+  }
+}
+
+/**
+ * updates the column categories.uppercats
+ *
+ * @param int $category_id
+ * @return void
+ */
+function update_uppercats( $category_id )
+{
+  global $page;
+
+  $final_id = $category_id;
+  $uppercats = array();
+
+  array_push( $uppercats, $category_id );
+  $uppercat = $page['plain_structure'][$category_id]['id_uppercat'];
+
+  while ( $uppercat != 'NULL' )
+  {
+    array_push( $uppercats, $uppercat );
+    $category_id = $page['plain_structure'][$category_id]['id_uppercat'];
+    $uppercat = $page['plain_structure'][$category_id]['id_uppercat'];
+  }
+
+  $string_uppercats = implode( ',', array_reverse( $uppercats ) );
+  $query = 'UPDATE '.PREFIX_TABLE.'categories';
+  $query.= ' SET uppercats = '."'".$string_uppercats."'";
+  $query.= ' WHERE id = '.$final_id;
+  $query.= ';';
+  mysql_query( $query );
+}
+
+/**
+ * returns an array with the ids of the restricted categories for the user
+ *
+ * Returns an array with the ids of the restricted categories for the
+ * user. If the $check_invisible parameter is set to true, invisible
+ * categorie are added to the restricted one in the array.
+ *
+ * @param int $user_id
+ * @param string $user_status
+ * @param bool $check_invisible
+ * @param bool $use_groups
+ * @return array
+ */
+function get_user_restrictions( $user_id, $user_status,
+                                $check_invisible, $use_groups = true )
+{
+  // 1. retrieving ids of private categories
+  $query = 'SELECT id';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= " WHERE status = 'private'";
+  $query.= ';';
+  $result = mysql_query( $query );
+  $privates = array();
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    array_push( $privates, $row['id'] );
+  }
+  // 2. retrieving all authorized categories for the user
+  $authorized = array();
+  // 2.1. retrieving authorized categories thanks to personnal user
+  //      authorization
+  $query = 'SELECT cat_id';
+  $query.= ' FROM '.PREFIX_TABLE.'user_access';
+  $query.= ' WHERE user_id = '.$user_id;
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    array_push( $authorized, $row['cat_id'] );
+  }
+  // 2.2. retrieving authorized categories thanks to group authorization to
+  //      which the user is a member
+  if ( $use_groups )
+  {
+    $query = 'SELECT ga.cat_id';
+    $query.= ' FROM '.PREFIX_TABLE.'user_group as ug';
+    $query.= ', '.PREFIX_TABLE.'group_access as ga';
+    $query.= ' WHERE ug.group_id = ga.group_id';
+    $query.= ' AND ug.user_id = '.$user_id;
+    $query.= ';';
+    $result = mysql_query( $query );
+    while ( $row = mysql_fetch_array( $result ) )
+    {
+      array_push( $authorized, $row['cat_id'] );
+    }
+    $authorized = array_unique( $authorized );
+  }
+
+  $forbidden = array();
+  foreach ( $privates as $private ) {
+    if ( !in_array( $private, $authorized ) )
+    {
+      array_push( $forbidden, $private );
+    }
+  }
+
+  if ( $check_invisible )
+  {
+    // 3. adding to the restricted categories, the invisible ones
+    if ( $user_status != 'admin' )
+    {
+      $query = 'SELECT id';
+      $query.= ' FROM '.PREFIX_TABLE.'categories';
+      $query.= " WHERE visible = 'false';";
+      $result = mysql_query( $query );
+      while ( $row = mysql_fetch_array( $result ) )
+      {
+        array_push( $forbidden, $row['id'] );
+      }
+    }
+  }
+  return array_unique( $forbidden );
+}
+
+/**
+ * finalizes operation for user_category table update
+ *
+ * This function is called by synchronization_*. It creates the
+ * $page['plain_structure'] and $page['structure'], get the SQL query to
+ * update user_category, clean user_category, and finally update the
+ * table. The users updates depends on the global array $user_restrictions.
+ *
+ * @return void
+ */
+function synchronize()
+{
+  global $user_restrictions,$page,$values;
+
+  update_user_category( $page['structure'] );
+
+  // cleaning user_category table for users to update
+  foreach( $user_restrictions as $user_id => $restrictions ) {
+    $query = 'DELETE';
+    $query.= ' FROM '.PREFIX_TABLE.'user_category';
+    $query.= ' WHERE user_id = '.$user_id;
+    $query.= ';';
+    mysql_query( $query );
+  }
+
+  $query = 'INSERT INTO '.PREFIX_TABLE.'user_category';
+  $query.= ' (user_id,category_id,date_last,nb_sub_categories) VALUES ';
+  $query.= $values;
+  $query.= ';';
+  mysql_query( $query );
+}
+
+/**
+ * synchronizes all users calculated informations
+ *
+ * fills global array $user_restrictions with all users and related
+ * restrictions before calling synchronize.
+ *
+ * @return void
+ */
+function synchronize_all_users()
+{
+  global $user_restrictions,$page;
+
+  $page['plain_structure'] = get_plain_structure();
+  $page['structure']       = create_structure( '' );
+  
+  $user_restrictions = array();
+  
+  $query = 'SELECT id';
+  $query.= ' FROM '.PREFIX_TABLE.'users';
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    $user_restrictions[$row['id']] = update_user_restrictions( $row['id'] );
+  }
+  synchronize();
+}
+
+/**
+ * synchronizes 1 user calculated informations
+ *
+ * fills global array $user_restrictions with the user id and its related
+ * restrictions before calling synchronize.
+ *
+ * @param int $user_id
+ * @return void
+ */
+function synchronize_user( $user_id )
+{
+  global $user_restrictions,$page;
+
+  $page['plain_structure'] = get_plain_structure();
+  $page['structure']       = create_structure( '' );
+  
+  $user_restrictions = array();
+  $user_restrictions[$user_id] = update_user_restrictions( $user_id );
+  synchronize();
+}
+
+/**
+ * synchronizes all users (belonging to the group) calculated informations
+ *
+ * fills global array $user_restrictions with all users and related
+ * restrictions before calling synchronize.
+ *
+ * @return void
+ */
+function synchronize_group( $group_id )
+{
+  global $user_restrictions,$page;
+
+  $page['plain_structure'] = get_plain_structure();
+  $page['structure']       = create_structure( '' );
+  
+  $user_restrictions = array();
+  
+  $query = 'SELECT id';
+  $query.= ' FROM '.PREFIX_TABLE.'users';
+  $query.= ', '.PREFIX_TABLE.'user_group';
+  $query.= ' WHERE group_id = '.$group_id;
+  $query.= ' AND id = user_id';
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    $user_restrictions[$row['id']] = update_user_restrictions( $row['id'] );
+  }
+  synchronize();
+}
+
+/**
+ * updates the calculated data users.forbidden_categories, it includes
+ * sub-categories of the direct forbidden categories
+ *
+ * @param nt $user_id
+ * @return array
+ */
+function update_user_restrictions( $user_id )
+{
+  $restrictions = get_user_all_restrictions( $user_id );
+
+  // update the users.forbidden_categories in database
+  $query = 'UPDATE '.PREFIX_TABLE.'users';
+  $query.= ' SET forbidden_categories = ';
+  if ( count( $restrictions ) > 0 )
+    $query.= "'".implode( ',', $restrictions )."'";
+  else
+    $query.= 'NULL';
+  $query .= ' WHERE id = '.$user_id;
+  $query.= ';';
+  mysql_query( $query );
+
+  return $restrictions;
+}
+
+/**
+ * returns all the restricted categories ids including sub-categories
+ *
+ * @param int $user_id
+ * @return array
+ */
+function get_user_all_restrictions( $user_id )
+{
+  global $page;
+  
+  $query = 'SELECT status';
+  $query.= ' FROM '.PREFIX_TABLE.'users';
+  $query.= ' WHERE id = '.$user_id;
+  $query.= ';';
+  $row = mysql_fetch_array( mysql_query( $query ) );
+  
+  $base_restrictions=get_user_restrictions($user_id,$row['status'],true,true);
+
+  $restrictions = $base_restrictions;
+  foreach ( $base_restrictions as $category_id ) {
+    echo $category_id.' is forbidden to user '.$user_id.'<br />';
+    $restrictions =
+      array_merge( $restrictions,
+                   $page['plain_structure'][$category_id]['all_subcats_ids'] );
+  }
+
+  return array_unique( $restrictions );
+}
+
+// The function is_user_allowed returns :
+//      - 0 : if the category is allowed with this $restrictions array
+//      - 1 : if this category is not allowed
+//      - 2 : if an uppercat category is not allowed
+// Note : the restrictions array must represent ONLY direct forbidden
+// categories, not all forbidden categories
+function is_user_allowed( $category_id, $restrictions )
+{
+  if ( in_array( $category_id, $restrictions ) ) return 1;
+
+  $query = 'SELECT uppercats';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= ' WHERE id = '.$category_id;
+  $query.= ';';
+  $row = mysql_fetch_array( mysql_query( $query ) );
+  $uppercats = explode( ',', $row['uppercats'] );
+  foreach ( $uppercats as $category_id ) {
+    if ( in_array( $category_id, $restrictions ) ) return 2;
+  }
+
+  // no restriction found : the user is allowed to access this category
+  return 0;
+}
+
+/**
+ * returns an array containing sub-directories which can be a category
+ *
+ * directories nammed "thumbnail" are omitted
+ *
+ * @param string $basedir
+ * @return array
+ */
+function get_category_directories( $basedir )
+{
+  $sub_dirs = array();
+
+  if ( $opendir = opendir( $basedir ) )
+  {
+    while ( $file = readdir( $opendir ) )
+    {
+      if ( $file != '.' and $file != '..'
+           and is_dir( $basedir.'/'.$file )
+           and $file != 'thumbnail' )
+      {
+        array_push( $sub_dirs, $file );
+      }
+    }
+  }
+  return $sub_dirs;
+}
+?>
diff --git a/admin/include/isadmin.inc.php b/admin/include/isadmin.inc.php
index 341fc65ba..14032c566 100644
--- a/admin/include/isadmin.inc.php
+++ b/admin/include/isadmin.inc.php
@@ -16,10 +16,7 @@
  *   the Free Software Foundation;                                         *
  *                                                                         *
  ***************************************************************************/
-define( "PREFIX_INCLUDE", '' );
 
-include_once( './include/config.inc.php' );
-include_once( './include/user.inc.php' );
 include( './admin/include/functions.php' );
 
 $isadmin = true;
diff --git a/admin/infos_images.php b/admin/infos_images.php
index 344573eac..f0ab9a39f 100644
--- a/admin/infos_images.php
+++ b/admin/infos_images.php
@@ -20,110 +20,104 @@
 include_once( './admin/include/isadmin.inc.php' );
 include_once( './template/'.$user['template'].'/htmlfunctions.inc.php' );
 //-------------------------------------------------------------- initialization
+$page['nb_image_page'] = 5;
+
 check_cat_id( $_GET['cat_id'] );
+
+$errors = array();
+
 if ( isset( $page['cat'] ) )
 {
 //--------------------------------------------------- update individual options
-  $query = 'SELECT id,file';
-  $query.= ' FROM '.PREFIX_TABLE.'images';
-  $query.= ' LEFT JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
-  $query.= ' WHERE category_id = '.$page['cat'];
-  $query.= ';';
-  $result = mysql_query( $query );
-  $i = 1;
-  while ( $row = mysql_fetch_array( $result ) )
+  if ( isset( $_POST['submit'] ) )
   {
-    $name          = 'name-'.$row['id'];
-    $author        = 'author-'.$row['id'];
-    $comment       = 'comment-'.$row['id'];
-    $date_creation = 'date_creation-'.$row['id'];
-    $keywords      = 'keywords-'.$row['id'];
-    if ( isset( $_POST[$name] ) )
+    if ( isset( $_POST['associate'] ) and $_POST['associate'] != '' )
     {
-      $query = 'UPDATE '.PREFIX_TABLE.'images';
-
-      $query.= ' SET name = ';
-      if ( $_POST[$name] == '' )
-        $query.= 'NULL';
-      else
-        $query.= "'".htmlentities( $_POST[$name], ENT_QUOTES )."'";
-
-      $query.= ', author = ';
-      if ( $_POST[$author] == '' )
-        $query.= 'NULL';
-      else
-        $query.= "'".htmlentities($_POST[$author],ENT_QUOTES)."'";
-
-      $query.= ', comment = ';
-      if ( $_POST[$comment] == '' )
-        $query.= 'NULL';
-      else
-        $query.= "'".htmlentities($_POST[$comment],ENT_QUOTES)."'";
-
-      $query.= ', date_creation = ';
-      if ( check_date_format( $_POST[$date_creation] ) )
-        $query.= "'".date_convert( $_POST[$date_creation] )."'";
-      else if ( $_POST[$date_creation] == '' )
-        $query.= 'NULL';
-
-      $query.= ', keywords = ';
-      $keywords_array = get_keywords( $_POST[$keywords] );
-      if ( count( $keywords_array ) == 0 )
-        $query.= 'NULL';
+      // does the uppercat id exists in the database ?
+      if ( !is_numeric( $_POST['associate'] ) )
+      {
+        array_push( $errors, $lang['cat_unknown_id'] );
+      }
       else
       {
-        $query.= "'";
-        foreach ( $keywords_array as $i => $keyword ) {
-          if ( $i > 0 ) $query.= ',';
-          $query.= $keyword;
-        }
-        $query.= "'";
+        $query = 'SELECT id';
+        $query.= ' FROM '.PREFIX_TABLE.'categories';
+        $query.= ' WHERE id = '.$_POST['associate'];
+        $query.= ';';
+        if ( mysql_num_rows( mysql_query( $query ) ) == 0 )
+          array_push( $errors, $lang['cat_unknown_id'] );
       }
-
-      $query.= ' WHERE id = '.$row['id'];
-      $query.= ';';
-      mysql_query( $query );
     }
-    // add link to another category
-    if ( $_POST['check-'.$row['id']] == 1 )
-    {
-      $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
-      $query.= ' (image_id,category_id) VALUES';
-      $query.= ' ('.$row['id'].','.$_POST['associate'].')';
-      $query.= ';';
-      mysql_query( $query );
-    }
-  }
-  update_category( $_POST['associate'] );
-//------------------------------------------------------ update general options
-  if ( $_POST['use_common_author'] == 1 )
-  {
-    $query = 'SELECT image_id';
-    $query.= ' FROM '.PREFIX_TABLE.'image_category';
+
+    $associate = false;
+    
+    $query = 'SELECT id,file';
+    $query.= ' FROM '.PREFIX_TABLE.'images';
+    $query.= ' INNER JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
     $query.= ' WHERE category_id = '.$page['cat'];
+    $query.= ';';
     $result = mysql_query( $query );
     while ( $row = mysql_fetch_array( $result ) )
     {
-      $query = 'UPDATE '.PREFIX_TABLE.'images';
-      if ( $_POST['author_cat'] == '' )
+      $name          = 'name-'.$row['id'];
+      $author        = 'author-'.$row['id'];
+      $comment       = 'comment-'.$row['id'];
+      $date_creation = 'date_creation-'.$row['id'];
+      $keywords      = 'keywords-'.$row['id'];
+      if ( isset( $_POST[$name] ) )
       {
-        $query.= ' SET author = NULL';
+        $query = 'UPDATE '.PREFIX_TABLE.'images';
+
+        $query.= ' SET name = ';
+        if ( $_POST[$name] == '' )
+          $query.= 'NULL';
+        else
+          $query.= "'".htmlentities( $_POST[$name], ENT_QUOTES )."'";
+
+        $query.= ', author = ';
+        if ( $_POST[$author] == '' )
+          $query.= 'NULL';
+        else
+          $query.= "'".htmlentities($_POST[$author],ENT_QUOTES)."'";
+
+        $query.= ', comment = ';
+        if ( $_POST[$comment] == '' )
+          $query.= 'NULL';
+        else
+          $query.= "'".htmlentities($_POST[$comment],ENT_QUOTES)."'";
+
+        $query.= ', date_creation = ';
+        if ( check_date_format( $_POST[$date_creation] ) )
+          $query.= "'".date_convert( $_POST[$date_creation] )."'";
+        else if ( $_POST[$date_creation] == '' )
+          $query.= 'NULL';
+
+        $query.= ', keywords = ';
+
+        $keywords_array = get_keywords( $_POST[$keywords] );
+        if ( count( $keywords_array ) == 0 ) $query.= 'NULL';
+        else $query.= "'".implode( ',', $keywords_array )."'";
+
+        $query.= ' WHERE id = '.$row['id'];
+        $query.= ';';
+        mysql_query( $query );
       }
-      else
+      // add link to another category
+      if ( isset( $_POST['check-'.$row['id']] ) and count( $errors ) == 0 )
       {
-        $query.= ' SET author = ';
-        $query.= "'".htmlentities( $_POST['author_cat'], ENT_QUOTES )."'";
+        $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
+        $query.= ' (image_id,category_id) VALUES';
+        $query.= ' ('.$row['id'].','.$_POST['associate'].')';
+        $query.= ';';
+        mysql_query( $query );
+        $associate = true;
       }
-      $query.= ' WHERE id = '.$row['image_id'];
-      $query.= ';';
-      mysql_query( $query );
     }
-  }
-  if ( $_POST['use_common_date_creation'] == 1 )
-  {
-    if ( check_date_format( $_POST['date_creation_cat'] ) )
+    update_category( $_POST['associate'] );
+    if ( $associate ) synchronize_all_users();
+//------------------------------------------------------ update general options
+    if ( isset( $_POST['use_common_author'] ) )
     {
-      $date = date_convert( $_POST['date_creation_cat'] );
       $query = 'SELECT image_id';
       $query.= ' FROM '.PREFIX_TABLE.'image_category';
       $query.= ' WHERE category_id = '.$page['cat'];
@@ -131,75 +125,102 @@ if ( isset( $page['cat'] ) )
       while ( $row = mysql_fetch_array( $result ) )
       {
         $query = 'UPDATE '.PREFIX_TABLE.'images';
-        if ( $_POST['date_creation_cat'] == '' )
+        if ( $_POST['author_cat'] == '' )
         {
-          $query.= ' SET date_creation = NULL';
+          $query.= ' SET author = NULL';
         }
         else
         {
-          $query.= " SET date_creation = '".$date."'";
+          $query.= ' SET author = ';
+          $query.= "'".htmlentities( $_POST['author_cat'], ENT_QUOTES )."'";
         }
         $query.= ' WHERE id = '.$row['image_id'];
         $query.= ';';
         mysql_query( $query );
       }
     }
-    else
-    {
-      echo $lang['err_date'];
-    }
-  }
-  if ( isset( $_POST['common_keywords'] ) and $_POST['keywords_cat'] != '' )
-  {
-    $query = 'SELECT id,keywords';
-    $query.= ' FROM '.PREFIX_TABLE.'images';
-    $query.= ' LEFT JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
-    $query.= ' WHERE category_id = '.$page['cat'];
-    $query.= ';';
-    $result = mysql_query( $query );
-    while ( $row = mysql_fetch_array( $result ) )
+    if ( isset( $_POST['use_common_date_creation'] ) )
     {
-      $specific_keywords = explode( ',', $row['keywords'] );
-      $common_keywords   = get_keywords( $_POST['keywords_cat'] );
-      // first possiblity : adding the given keywords to all the pictures
-      if ( $_POST['common_keywords'] == 'add' )
-      {
-        $keywords = array_merge( $specific_keywords, $common_keywords );
-        $keywords = array_unique( $keywords );
-      }
-      // second possiblity : removing the given keywords from all pictures
-      // (without deleting the other specific keywords
-      if ( $_POST['common_keywords'] == 'remove' )
+      if ( check_date_format( $_POST['date_creation_cat'] ) )
       {
-        $keywords = array_diff( $specific_keywords, $common_keywords );
+        $date = date_convert( $_POST['date_creation_cat'] );
+        $query = 'SELECT image_id';
+        $query.= ' FROM '.PREFIX_TABLE.'image_category';
+        $query.= ' WHERE category_id = '.$page['cat'];
+        $result = mysql_query( $query );
+        while ( $row = mysql_fetch_array( $result ) )
+        {
+          $query = 'UPDATE '.PREFIX_TABLE.'images';
+          if ( $_POST['date_creation_cat'] == '' )
+          {
+            $query.= ' SET date_creation = NULL';
+          }
+          else
+          {
+            $query.= " SET date_creation = '".$date."'";
+          }
+          $query.= ' WHERE id = '.$row['image_id'];
+          $query.= ';';
+          mysql_query( $query );
+        }
       }
-      // cleaning the keywords array, sometimes, an empty value still remain
-      $keywords = array_remove( $keywords, '' );
-      // updating the picture with new keywords array
-      $query = 'UPDATE '.PREFIX_TABLE.'images';
-      $query.= ' SET keywords = ';
-      if ( count( $keywords ) == 0 )
+      else
       {
-        $query.= 'NULL';
+        array_push( $errors, $lang['err_date'] );
       }
-      else
+    }
+    if ( isset( $_POST['common_keywords'] ) and $_POST['keywords_cat'] != '' )
+    {
+      $query = 'SELECT id,keywords';
+      $query.= ' FROM '.PREFIX_TABLE.'images';
+      $query.= ' INNER JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
+      $query.= ' WHERE category_id = '.$page['cat'];
+      $query.= ';';
+      $result = mysql_query( $query );
+      while ( $row = mysql_fetch_array( $result ) )
       {
-        $query.= '"';
-        $i = 0;
-        foreach ( $keywords as $keyword ) {
-          if ( $i++ > 0 ) $query.= ',';
-          $query.= $keyword;
+        if ( !isset( $row['keywords'] ) ) $specific_keywords = array();
+        else $specific_keywords = explode( ',', $row['keywords'] );
+        
+        $common_keywords   = get_keywords( $_POST['keywords_cat'] );
+        // first possiblity : adding the given keywords to all the pictures
+        if ( $_POST['common_keywords'] == 'add' )
+        {
+          $keywords = array_merge( $specific_keywords, $common_keywords );
+          $keywords = array_unique( $keywords );
+        }
+        // second possiblity : removing the given keywords from all pictures
+        // (without deleting the other specific keywords
+        if ( $_POST['common_keywords'] == 'remove' )
+        {
+          $keywords = array_diff( $specific_keywords, $common_keywords );
+        }
+        // cleaning the keywords array, sometimes, an empty value still remain
+        $keywords = array_remove( $keywords, '' );
+        // updating the picture with new keywords array
+        $query = 'UPDATE '.PREFIX_TABLE.'images';
+        $query.= ' SET keywords = ';
+        if ( count( $keywords ) == 0 )
+        {
+          $query.= 'NULL';
+        }
+        else
+        {
+          $query.= '"';
+          $i = 0;
+          foreach ( $keywords as $keyword ) {
+            if ( $i++ > 0 ) $query.= ',';
+            $query.= $keyword;
+          }
+          $query.= '"';
         }
-        $query.= '"';
+        $query.= ' WHERE id = '.$row['id'];
+        $query.= ';';
+        mysql_query( $query );
       }
-      $query.= ' WHERE id = '.$row['id'];
-      $query.= ';';
-      mysql_query( $query );
     }
   }
 //--------------------------------------------------------- form initialization
-  $page['nb_image_page'] = 5;
-
   if( !isset( $_GET['start'] )
       or !is_numeric( $_GET['start'] )
       or ( is_numeric( $_GET['start'] ) and $_GET['start'] < 0 ) )
@@ -211,13 +232,12 @@ if ( isset( $page['cat'] ) )
     $page['start'] = $_GET['start'];
   }
 
-  if ( is_numeric( $_GET['num'] ) and $_GET['num'] >= 0 )
+  if ( isset($_GET['num']) and is_numeric($_GET['num']) and $_GET['num'] >= 0 )
   {
     $page['start'] =
       floor( $_GET['num'] / $page['nb_image_page'] ) * $page['nb_image_page'];
   }
   // retrieving category information
-  $page['plain_structure'] = get_plain_structure();
   $result = get_cat_info( $page['cat'] );
   $cat['name'] = $result['name'];
   $cat['nb_images'] = $result['nb_images'];
@@ -228,9 +248,21 @@ if ( isset( $page['cat'] ) )
                 'infoimage_title','infoimage_comment',
                 'infoimage_creation_date','keywords',
                 'infoimage_addtoall','infoimage_removefromall',
-                'infoimage_keyword_separation','infoimage_associate' );
+                'infoimage_keyword_separation','infoimage_associate',
+                'errors_title' );
   templatize_array( $tpl, 'lang', $sub );
   $vtp->setGlobalVar( $sub, 'user_template',   $user['template'] );
+//-------------------------------------------------------------- errors display
+if ( count( $errors ) != 0 )
+{
+  $vtp->addSession( $sub, 'errors' );
+  foreach ( $errors as $error ) {
+    $vtp->addSession( $sub, 'li' );
+    $vtp->setVar( $sub, 'li.content', $error );
+    $vtp->closeSession( $sub, 'li' );
+  }
+  $vtp->closeSession( $sub, 'errors' );
+}
 //------------------------------------------------------------------------ form
   $url = './admin.php?page=infos_images&amp;cat_id='.$page['cat'];
   $url.= '&amp;start='.$page['start'];
@@ -243,10 +275,13 @@ if ( isset( $page['cat'] ) )
 
   $array_cat_directories = array();
 
-  $query = 'SELECT id,file,comment,author,tn_ext,name,date_creation,keywords';
-  $query.= ',storage_category_id,category_id';
+  $infos = array( 'id','file','comment','author','tn_ext','name'
+                  ,'date_creation','keywords','storage_category_id'
+                  ,'category_id' );
+  
+  $query = 'SELECT '.implode( ',', $infos );
   $query.= ' FROM '.PREFIX_TABLE.'images';
-  $query.= ' LEFT JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
+  $query.= ' INNER JOIN '.PREFIX_TABLE.'image_category ON id = image_id';
   $query.= ' WHERE category_id = '.$page['cat'];
   $query.= $conf['order_by'];
   $query.= ' LIMIT '.$page['start'].','.$page['nb_image_page'];
@@ -254,6 +289,8 @@ if ( isset( $page['cat'] ) )
   $result = mysql_query( $query );
   while ( $row = mysql_fetch_array( $result ) )
   {
+    foreach ($infos as $info) { if (!isset($row[$info])) $row[$info] = ''; }
+    
     $vtp->addSession( $sub, 'picture' );
     $vtp->setVar( $sub, 'picture.id', $row['id'] );
     $vtp->setVar( $sub, 'picture.filename', $row['file'] );
@@ -266,7 +303,7 @@ if ( isset( $page['cat'] ) )
     $file = get_filename_wo_extension( $row['file'] );
     $vtp->setVar( $sub, 'picture.default_name', $file );
     // creating url to thumbnail
-    if ( $array_cat_directories[$row['storage_category_id']] == '' )
+    if ( !isset( $array_cat_directories[$row['storage_category_id']] ) )
     {
       $array_cat_directories[$row['storage_category_id']] =
         get_complete_dir( $row['storage_category_id'] );
@@ -279,8 +316,29 @@ if ( isset( $page['cat'] ) )
     $vtp->setVar( $sub, 'picture.url', add_session_id( $url ) );
     $vtp->closeSession( $sub, 'picture' );
   }
-  $structure = create_structure( '', array() );
-  display_categories( $structure, '&nbsp;' );
+  // Virtualy associate a picture to a category
+  //
+  // We only show a List Of Values if the number of categories is less than
+  // $conf['max_LOV_categories']
+  $query = 'SELECT COUNT(id) AS nb_total_categories';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= ';';
+  $row = mysql_fetch_array( mysql_query( $query ) );
+  if ( $row['nb_total_categories'] < $conf['max_LOV_categories'] )
+  {
+    $vtp->addSession( $sub, 'associate_LOV' );
+    $page['plain_structure'] = get_plain_structure( true );
+    $structure = create_structure( '', array() );
+    display_categories( $structure, '&nbsp;' );
+    $vtp->closeSession( $sub, 'associate_LOV' );
+  }
+  // else, we only display a small text field, we suppose the administrator
+  // knows the id of its category
+  else
+  {
+    $vtp->addSession( $sub, 'associate_text' );
+    $vtp->closeSession( $sub, 'associate_text' );
+  }
 }
 //----------------------------------------------------------- sending html code
 $vtp->Parse( $handle , 'sub', $sub );
diff --git a/admin/phpwebgallery_structure.sql b/admin/phpwebgallery_structure.sql
index d6797c162..d1c5343a6 100644
--- a/admin/phpwebgallery_structure.sql
+++ b/admin/phpwebgallery_structure.sql
@@ -1,6 +1,6 @@
 -- MySQL dump 8.21
 --
--- Host: localhost    Database: devel
+-- Host: localhost    Database: perfs_test
 ---------------------------------------------------------
 -- Server version	3.23.49-log
 
@@ -23,7 +23,10 @@ CREATE TABLE phpwebgallery_categories (
   visible enum('true','false') NOT NULL default 'true',
   uploadable enum('true','false') NOT NULL default 'false',
   representative_picture_id mediumint(8) unsigned default NULL,
-  PRIMARY KEY  (id)
+  uppercats varchar(255) NOT NULL default '',
+  PRIMARY KEY  (id),
+  KEY id (id),
+  KEY id_uppercat (id_uppercat)
 ) TYPE=MyISAM;
 
 --
@@ -125,7 +128,9 @@ DROP TABLE IF EXISTS phpwebgallery_image_category;
 CREATE TABLE phpwebgallery_image_category (
   image_id mediumint(8) unsigned NOT NULL default '0',
   category_id smallint(5) unsigned NOT NULL default '0',
-  PRIMARY KEY  (image_id,category_id)
+  PRIMARY KEY  (image_id,category_id),
+  KEY category_id (category_id),
+  KEY image_id (image_id)
 ) TYPE=MyISAM;
 
 --
@@ -189,6 +194,19 @@ CREATE TABLE phpwebgallery_user_access (
 ) TYPE=MyISAM;
 
 --
+-- Table structure for table 'phpwebgallery_user_category'
+--
+
+DROP TABLE IF EXISTS phpwebgallery_user_category;
+CREATE TABLE phpwebgallery_user_category (
+  user_id smallint(5) unsigned NOT NULL default '0',
+  category_id smallint(5) unsigned NOT NULL default '0',
+  date_last date default NULL,
+  nb_sub_categories smallint(5) unsigned NOT NULL default '0',
+  PRIMARY KEY  (user_id,category_id)
+) TYPE=MyISAM;
+
+--
 -- Table structure for table 'phpwebgallery_user_group'
 --
 
@@ -220,6 +238,7 @@ CREATE TABLE phpwebgallery_users (
   short_period tinyint(3) unsigned NOT NULL default '7',
   long_period tinyint(3) unsigned NOT NULL default '14',
   template varchar(255) NOT NULL default 'default',
+  forbidden_categories text,
   PRIMARY KEY  (id),
   UNIQUE KEY username (username)
 ) TYPE=MyISAM;
diff --git a/admin/picture_modify.php b/admin/picture_modify.php
index b6bfadc19..be9ffd7bc 100644
--- a/admin/picture_modify.php
+++ b/admin/picture_modify.php
@@ -18,8 +18,6 @@
  ***************************************************************************/
 
 include_once( './admin/include/isadmin.inc.php' );
-//----------------------------------------- categories structure initialization
-$page['plain_structure'] = get_plain_structure();
 //--------------------------------------------------------- update informations
 $errors = array();
 // first, we verify whether there is a mistake on the given creation date
@@ -87,7 +85,7 @@ if ( isset( $_POST['submit'] ) )
     // if the user ask the picture to be the representative picture of its
     // category, the category is updated in the database (without wondering
     // if this picture was already the representative one)
-    if ( $_POST['representative-'.$row['category_id']] == 1 )
+    if ( isset($_POST['representative-'.$row['category_id']]) )
     {
       $query = 'UPDATE '.PREFIX_TABLE.'categories';
       $query.= ' SET representative_picture_id = '.$_GET['image_id'];
@@ -97,7 +95,8 @@ if ( isset( $_POST['submit'] ) )
     }
     // if the user ask this picture to be not any more the representative,
     // we have to set the representative_picture_id of this category to NULL
-    else if ( $row['representative_picture_id'] == $_GET['image_id'] )
+    else if ( isset( $row['representative_picture_id'] )
+              and $row['representative_picture_id'] == $_GET['image_id'] )
     {
       $query = 'UPDATE '.PREFIX_TABLE.'categories';
       $query.= ' SET representative_picture_id = NULL';
@@ -106,14 +105,35 @@ if ( isset( $_POST['submit'] ) )
       mysql_query( $query );
     }
   }
+  $associate_or_dissociate = false;
   // associate with a new category ?
-  if ( $_POST['associate'] != '-1' )
+  if ( $_POST['associate'] != '-1' and $_POST['associate'] != '' )
+  {
+    // does the uppercat id exists in the database ?
+    if ( !is_numeric( $_POST['associate'] ) )
+    {
+      array_push( $errors, $lang['cat_unknown_id'] );
+    }
+    else
+    {
+      $query = 'SELECT id';
+      $query.= ' FROM '.PREFIX_TABLE.'categories';
+      $query.= ' WHERE id = '.$_POST['associate'];
+      $query.= ';';
+      if ( mysql_num_rows( mysql_query( $query ) ) == 0 )
+        array_push( $errors, $lang['cat_unknown_id'] );
+    }
+  }
+  if ( $_POST['associate'] != '-1'
+       and $_POST['associate'] != ''
+       and count( $errors ) == 0 )
   {
     $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
     $query.= ' (category_id,image_id) VALUES ';
     $query.= '('.$_POST['associate'].','.$_GET['image_id'].')';
     $query.= ';';
     mysql_query( $query);
+    $associate_or_dissociate = true;
     update_category( $_POST['associate'] );
   }
   // dissociate any category ?
@@ -125,16 +145,21 @@ if ( isset( $_POST['submit'] ) )
   $result = mysql_query( $query );
   while ( $row = mysql_fetch_array( $result ) )
   {
-    if ( $_POST['dissociate-'.$row['category_id']] == 1 )
+    if ( isset($_POST['dissociate-'.$row['category_id']]) )
     {
       $query = 'DELETE FROM '.PREFIX_TABLE.'image_category';
       $query.= ' WHERE image_id = '.$_GET['image_id'];
       $query.= ' AND category_id = '.$row['category_id'];
       $query.= ';';
       mysql_query( $query );
+      $associate_or_dissociate = true;
       update_category( $row['category_id'] );
     }
   }
+  if ( $associate_or_dissociate )
+  {
+    synchronize_all_users();
+  }
 }
 //----------------------------------------------------- template initialization
 $sub = $vtp->Open(
@@ -162,12 +187,19 @@ if ( count( $errors ) != 0 )
 $action = './admin.php?'.$_SERVER['QUERY_STRING'];
 $vtp->setVar( $sub, 'form_action', $action );
 // retrieving direct information about picture
-$query = 'SELECT file,date_available,date_creation,tn_ext,name,filesize';
-$query.= ',width,height,author,comment,keywords,storage_category_id';
+$infos = array( 'file','date_available','date_creation','tn_ext','name'
+                ,'filesize','width','height','author','comment','keywords'
+                ,'storage_category_id' );
+$query = 'SELECT '. implode( ',', $infos );
 $query.= ' FROM '.PREFIX_TABLE.'images';
 $query.= ' WHERE id = '.$_GET['image_id'];
 $query.= ';';
 $row = mysql_fetch_array( mysql_query( $query ) );
+
+foreach ( $infos as $info ) {
+  if ( !isset( $row[$info] ) ) $row[$info] = '';
+}
+
 // picture title
 if ( $row['name'] == '' )
 {
@@ -290,7 +322,8 @@ while ( $row = mysql_fetch_array( $result ) )
     $vtp->setVar( $sub, 'linked_category.invisible', $invisible_string );
   }
 
-  if ( $row['representative_picture_id'] == $_GET['image_id'] )
+  if ( isset( $row['representative_picture_id'] )
+       and $row['representative_picture_id'] == $_GET['image_id'] )
   {
     $vtp->setVar( $sub, 'linked_category.representative_checked',
                   ' checked="checked"' );
@@ -306,12 +339,32 @@ if ( mysql_num_rows( $result ) > 0 )
   $vtp->closeSession( $sub, 'dissociate' );
 }
 // associate to another category ?
-$vtp->addSession( $sub, 'associate_cat' );
-$vtp->setVar( $sub, 'associate_cat.value', '-1' );
-$vtp->setVar( $sub, 'associate_cat.content', '' );
-$vtp->closeSession( $sub, 'associate_cat' );
-$structure = create_structure( '', array() );
-display_categories( $structure, '&nbsp;' );
+//
+// We only show a List Of Values if the number of categories is less than
+// $conf['max_LOV_categories']
+$query = 'SELECT COUNT(id) AS nb_total_categories';
+$query.= ' FROM '.PREFIX_TABLE.'categories';
+$query.= ';';
+$row = mysql_fetch_array( mysql_query( $query ) );
+if ( $row['nb_total_categories'] < $conf['max_LOV_categories'] )
+{
+  $vtp->addSession( $sub, 'associate_LOV' );
+  $vtp->addSession( $sub, 'associate_cat' );
+  $vtp->setVar( $sub, 'associate_cat.value', '-1' );
+  $vtp->setVar( $sub, 'associate_cat.content', '' );
+  $vtp->closeSession( $sub, 'associate_cat' );
+  $page['plain_structure'] = get_plain_structure( true );
+  $structure = create_structure( '', array() );
+  display_categories( $structure, '&nbsp;' );
+  $vtp->closeSession( $sub, 'associate_LOV' );
+}
+// else, we only display a small text field, we suppose the administrator
+// knows the id of its category
+else
+{
+  $vtp->addSession( $sub, 'associate_text' );
+  $vtp->closeSession( $sub, 'associate_text' );
+}
 //----------------------------------------------------------- sending html code
 $vtp->Parse( $handle , 'sub', $sub );
 ?>
\ No newline at end of file
diff --git a/admin/stats.php b/admin/stats.php
index 01780a95e..ba33a1582 100644
--- a/admin/stats.php
+++ b/admin/stats.php
@@ -42,13 +42,15 @@ $tpl = array( 'stats_last_days','date','login',
 templatize_array( $tpl, 'lang', $sub );
 $vtp->setGlobalVar( $sub, 'user_template', $user['template'] );
 //--------------------------------------------------- number of days to display
-if ( isset( $_GET['last_days'] ) ) define( "MAX_DAYS", $_GET['last_days'] );
-else                               define( "MAX_DAYS", 0 );
+if ( isset( $_GET['last_days'] ) ) define( 'MAX_DAYS', $_GET['last_days'] );
+else                               define( 'MAX_DAYS', 0 );
 
 foreach ( $conf['last_days'] as $option ) {
   $vtp->addSession( $sub, 'last_day_option' );
   $vtp->setVar( $sub, 'last_day_option.option', $option );
-  $url = './admin.php?page=stats&amp;expand='.$_GET['expand'];
+  $url = './admin.php?page=stats';
+  if (isset($_GET['expand']))
+	  $url .='&amp;expand='.$_GET['expand'];
   $url.= '&amp;last_days='.($option - 1);
   $vtp->setVar( $sub, 'last_day_option.link', add_session_id( $url ) );
   if ( $option == MAX_DAYS + 1 )
@@ -59,12 +61,18 @@ foreach ( $conf['last_days'] as $option ) {
 }
 //---------------------------------------------------------------- log  history
 // empty link
-$url = './admin.php?page=stats&amp;last_days='.$_GET['last_days'];
-$url.= '&amp;expand='.$_GET['expand'];
+$url = './admin.php?page=stats';
+if (isset($_GET['last_days']))
+  	$url .='&amp;last_days='.$_GET['last_days'];
+// expand array management
+$expand_days = array();
+if (isset($_GET['expand']))
+{
+	$url.= '&amp;expand='.$_GET['expand'];
+	$expand_days = explode( ',', $_GET['expand'] );
+}
 $url.= '&amp;act=empty';
 $vtp->setVar( $sub, 'emply_url', add_session_id( $url ) );
-// expand array management
-$expand_days = explode( ',', $_GET['expand'] );
 $page['expand_days'] = array();
 foreach ( $expand_days as $expand_day ) {
   if ( is_numeric( $expand_day ) )
@@ -99,7 +107,9 @@ for ( $i = 0; $i <= MAX_DAYS; $i++ )
     $vtp->setVar( $sub, 'day.open_or_close', $lang['open'] );
     array_push( $local_expand, $i );
   }
-  $url = './admin.php?page=stats&amp;last_days='.$_GET['last_days'];
+  $url = './admin.php?page=stats';
+  if (isset($_GET['last_days']))
+  	$url.= '&amp;last_days='.$_GET['last_days'];
   $url.= '&amp;expand='.implode( ',', $local_expand );
   $vtp->setVar( $sub, 'day.url', add_session_id( $url ) );
   // date displayed like this (in English ) :
diff --git a/admin/thumbnail.php b/admin/thumbnail.php
index 0abbae506..ae44b311c 100644
--- a/admin/thumbnail.php
+++ b/admin/thumbnail.php
@@ -253,9 +253,8 @@ function get_displayed_dirs( $dir, $indent )
     }
     $vtp->closeSession( $sub, 'dir' );
     // recursive call
-    $dirs.= get_displayed_dirs( $dir.'/'.$sub_dir,
-                                $indent+30 );
-    
+    get_displayed_dirs( $dir.'/'.$sub_dir,
+                                $indent+30 );    
   }
 }
 //----------------------------------------------------- template initialization
@@ -359,7 +358,7 @@ if ( isset( $_GET['dir'] ) )
     $url = './admin.php?page=thumbnail&amp;dir='.$_GET['dir'];
     $vtp->setVar( $sub, 'params.action', add_session_id( $url ) );
     // GD version selected...
-    if ( $_POST['gd'] == 1 )
+    if ( isset( $_POST['gd'] ) and $_POST['gd'] == 1 )
     {
       $vtp->setVar( $sub, 'params.gd1_checked', ' checked="checked"' );
     }
@@ -387,10 +386,12 @@ if ( isset( $_GET['dir'] ) )
     }
     // options for the number of picture to miniaturize : "n"
     $options = array( 5,10,20,40 );
+    if ( isset( $_POST['n'] ) ) $n = $_POST['n'];
+    else                        $n = 5;
     foreach ( $options as $option ) {
       $vtp->addSession( $sub, 'n_option' );
       $vtp->setVar( $sub, 'n_option.option', $option );
-      if ( $option == $_POST['n'] )
+      if ( $option == $n )
       {
         $vtp->setVar( $sub, 'n_option.selected', ' selected="selected"' );
       }
diff --git a/admin/update.php b/admin/update.php
index df1c6ebff..4e13e466d 100644
--- a/admin/update.php
+++ b/admin/update.php
@@ -2,7 +2,7 @@
 /***************************************************************************
  *                                update.php                               *
  *                            ------------------                           *
- *   application   : PhpWebGallery 1.3 <http://phpwebgallery.net>          *
+ *   application   : PhpWebGallery 1.4 <http://phpwebgallery.net>          *
  *   author        : Pierrick LE GALL <pierrick@z0rglub.com>               *
  *                                                                         *
  *   $Id$
@@ -19,142 +19,162 @@
 
 include_once( './admin/include/isadmin.inc.php' );
 //------------------------------------------------------------------- functions
-function insert_local_category( $cat_id )
+function insert_local_category( $id_uppercat )
 {
   global $conf, $page, $user, $lang;
-
-  $site_id = 1;
+ 
+  $uppercats = '';
+  $output = '';
 
   // 0. retrieving informations on the category to display
   $cat_directory = './galleries';
-
-  if ( is_numeric( $cat_id ) )
+  if ( is_numeric( $id_uppercat ) )
   {
-    $cat_directory.= '/'.get_local_dir( $cat_id );
-    $result = get_cat_info( $cat_id );
+    $query = 'SELECT name,uppercats,dir';
+    $query.= ' FROM '.PREFIX_TABLE.'categories';
+    $query.= ' WHERE id = '.$id_uppercat;
+    $query.= ';';
+    $row = mysql_fetch_array( mysql_query( $query ) );
+    $uppercats = $row['uppercats'];
+    $name      = $row['name'];
+    $dir       = $row['dir'];
+
+    $upper_array = explode( ',', $uppercats );
+
+    $local_dir = '';
+
+    $database_dirs = array();
+    $query = 'SELECT id,dir';
+    $query.= ' FROM '.PREFIX_TABLE.'categories';
+    $query.= ' WHERE id IN ('.$uppercats.')';
+    $query.= ';';
+    $result = mysql_query( $query );
+    while( $row = mysql_fetch_array( $result ) )
+    {
+      $database_dirs[$row['id']] = $row['dir'];
+    }
+    foreach ( $upper_array as $id ) {
+      $local_dir.= $database_dirs[$id].'/';
+    }
+
+    $cat_directory.= '/'.$local_dir;
+
     // 1. display the category name to update
     $src = './template/'.$user['template'].'/admin/images/puce.gif';
     $output = '<img src="'.$src.'" alt="&gt;" />';
-    $output.= '<span style="font-weight:bold;">'.$result['name'][0].'</span>';
-    $output.= ' [ '.$result['dir'].' ]';
+    $output.= '<span style="font-weight:bold;">'.$name.'</span>';
+    $output.= ' [ '.$dir.' ]';
     $output.= '<div class="retrait">';
 
     // 2. we search pictures of the category only if the update is for all
     //    or a cat_id is specified
     if ( isset( $page['cat'] ) or $_GET['update'] == 'all' )
     {
-      $output.= insert_local_image( $cat_directory, $cat_id );
+      $output.= insert_local_image( $cat_directory, $id_uppercat );
     }
   }
 
-  // 3. we have to remove the categories of the database not present anymore
-  $query = 'SELECT id';
+  $sub_dirs = get_category_directories( $cat_directory );
+
+  $sub_category_dirs = array();
+  $query = 'SELECT id,dir';
   $query.= ' FROM '.PREFIX_TABLE.'categories';
-  $query.= ' WHERE site_id = '.$site_id;
-  if ( !is_numeric( $cat_id ) )
-  {
-    $query.= ' AND id_uppercat IS NULL';
-  }
-  else
-  {
-    $query.= ' AND id_uppercat = '.$cat_id;
-  }
+  $query.= ' WHERE site_id = 1';
+  if (!is_numeric($id_uppercat)) $query.= ' AND id_uppercat IS NULL';
+  else                           $query.= ' AND id_uppercat = '.$id_uppercat;
+  $query.= ' AND dir IS NOT NULL'; // virtual categories not taken
   $query.= ';';
   $result = mysql_query( $query );
   while ( $row = mysql_fetch_array( $result ) )
   {
-    // retrieving the directory
-    $rep = './galleries/'.get_local_dir( $row['id'] );
-    // is the directory present ?
-    if ( !is_dir( $rep ) ) delete_category( $row['id'] );
+    $sub_category_dirs[$row['id']] = $row['dir'];
   }
-  // 4. retrieving the sub-directories
-  $subdirs = array();
-  $dirs = '';
-  if ( $opendir = opendir( $cat_directory ) )
-  {
-    while ( $file = readdir( $opendir ) )
+  
+  // 3. we have to remove the categories of the database not present anymore
+  foreach ( $sub_category_dirs as $id => $dir ) {
+    if ( !in_array( $dir, $sub_dirs ) ) delete_category( $id );
+  }
+
+  // array of new categories to insert
+  $inserts = array();
+  
+  foreach ( $sub_dirs as $sub_dir ) {
+    // 5. Is the category already existing ? we create a subcat if not
+    //    existing
+    $category_id = array_search( $sub_dir, $sub_category_dirs );
+    if ( !is_numeric( $category_id ) )
     {
-      if ( $file != '.'
-           and $file != '..'
-           and is_dir ( $cat_directory.'/'.$file )
-           and $file != 'thumbnail' )
+      if ( preg_match( '/^[a-zA-Z0-9-_.]+$/', $sub_dir ) )
       {
-        if ( preg_match( '/^[a-zA-Z0-9-_.]+$/', $file ) )
-          array_push( $subdirs, $file );
-        else
-        {
-          $output.= '<span style="color:red;">"'.$file.'" : ';
-          $output.= $lang['update_wrong_dirname'].'</span><br />';
-          // if the category even exists (from a previous release of
-          // PhpWebGallery), we keep it in our $subdirs array
-          $query = 'SELECT id';
-          $query.= ' FROM '.PREFIX_TABLE.'categories';
-          $query.= ' WHERE site_id = '.$site_id;
-          $query.= " AND dir = '".$file."'";
-          $query.= ' AND id_uppercat';
-          if ( !is_numeric( $cat_id ) ) $query.= ' IS NULL';
-          else                          $query.= ' = '.$cat_id;
-          $query.= ';';
-          $result = mysql_query( $query );
-          if ( mysql_num_rows( $result ) != 0 )
-          {
-            array_push( $subdirs, $file );
-          }
-        }
+        $name = str_replace( '_', ' ', $sub_dir );
+
+        $value = "('".$sub_dir."','".$name."',1";
+        if ( !is_numeric( $id_uppercat ) ) $value.= ',NULL';
+        else                               $value.= ','.$id_uppercat;
+        $value.= ",'undef'";
+        $value.= ')';
+        array_push( $inserts, $value );
+      }
+      else
+      {
+        $output.= '<span style="color:red;">"'.$sub_dir.'" : ';
+        $output.= $lang['update_wrong_dirname'].'</span><br />';
       }
     }
   }
-  foreach ( $subdirs as $subdir ) {
-    // 5. Is the category already existing ? we create a subcat if not
-    //    existing
-    $category_id = '';
-    $query = 'SELECT id';
-    $query.= ' FROM '.PREFIX_TABLE.'categories';
-    $query.= ' WHERE site_id = '.$site_id;
-    $query.= " AND dir = '".$subdir."'";
-    $query.= ' AND id_uppercat';
-    if ( !is_numeric( $cat_id ) ) $query.= ' IS NULL';
-    else                          $query.= ' = '.$cat_id;
+
+  // we have to create the category
+  if ( count( $inserts ) > 0 )
+  {
+    $query = 'INSERT INTO '.PREFIX_TABLE.'categories';
+    $query.= ' (dir,name,site_id,id_uppercat,uppercats) VALUES ';
+    $query.= implode( ',', $inserts );
     $query.= ';';
-    $result = mysql_query( $query );
-    if ( mysql_num_rows( $result ) == 0 )
-    {
-      $name = str_replace( '_', ' ', $subdir );
-      // we have to create the category
-      $query = 'INSERT INTO '.PREFIX_TABLE.'categories';
-      $query.= ' (dir,name,site_id,id_uppercat) VALUES';
-      $query.= " ('".$subdir."','".$name."','".$site_id."'";
-      if ( !is_numeric( $cat_id ) ) $query.= ',NULL';
-      else                          $query.= ",'".$cat_id."'";
-      $query.= ');';
-      mysql_query( $query );
-      $category_id = mysql_insert_id();
-      // regeneration of the plain_structure to integrate the new category
-      $page['plain_structure'] = get_plain_structure();
-    }
-    else
-    {
-      // we get the already registered id
-      $row = mysql_fetch_array( $result );
-      $category_id = $row['id'];
-    }
-    // 6. recursive call
-    $output.= insert_local_category( $category_id );
+    mysql_query( $query );
+    // updating uppercats field
+    $query = 'UPDATE '.PREFIX_TABLE.'categories';
+    $query.= ' SET uppercats = ';
+    if ( $uppercats != '' ) $query.= "CONCAT('".$uppercats."',',',id)";
+    else                    $query.= 'id';
+    $query.= ' WHERE id_uppercat ';
+    if (!is_numeric($id_uppercat)) $query.= 'IS NULL';
+    else                           $query.= '= '.$id_uppercat;
+    $query.= ';';
+    mysql_query( $query );
   }
-		
-  if ( is_numeric( $cat_id ) )
+
+  // Recursive call on the sub-categories (not virtual ones)
+  $query = 'SELECT id';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= ' WHERE site_id = 1';
+  if (!is_numeric($id_uppercat)) $query.= ' AND id_uppercat IS NULL';
+  else                           $query.= ' AND id_uppercat = '.$id_uppercat;
+  $query.= ' AND dir IS NOT NULL'; // virtual categories not taken
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    $output.= insert_local_category( $row['id'] );
+  }
+
+  if ( is_numeric( $id_uppercat ) )
   {
     $output.= '</div>';
   }
   return $output;
 }
-	
-function insert_local_image( $rep, $category_id )
+
+function insert_local_image( $dir, $category_id )
 {
   global $lang,$conf,$count_new;
 
   $output = '';
+
+  // fs means filesystem : $fs_pictures contains pictures in the filesystem
+  // found in $dir, $fs_thumbnails contains thumbnails...
+  $fs_pictures   = get_picture_files( $dir );
+  $fs_thumbnails = get_thumb_files( $dir.'thumbnail' );
+
   // we have to delete all the images from the database that :
   //     - are not in the directory anymore
   //     - don't have the associated thumbnail available anymore
@@ -165,157 +185,187 @@ function insert_local_image( $rep, $category_id )
   $result = mysql_query( $query );
   while ( $row = mysql_fetch_array( $result ) )
   {
-    $lien_image = $rep.'/'.$row['file'];
-    $lien_thumbnail = $rep.'/thumbnail/'.$conf['prefix_thumbnail'];
-    $lien_thumbnail.= get_filename_wo_extension( $row['file'] );
-    $lien_thumbnail.= '.'.$row['tn_ext'];
-		
-    if ( !is_file ( $lien_image ) or !is_file ( $lien_thumbnail ) )
+    $pic_to_delete = false;
+    if ( !in_array( $row['file'], $fs_pictures ) )
     {
-      if ( !is_file ( $lien_image ) )
-      {
-        $output.= $row['file'];
-        $output.= ' <span style="font-weight:bold;">';
-        $output.= $lang['update_disappeared'].'</span><br />';
-      }
-      if ( !is_file ( $lien_thumbnail ) )
-      {
-        $output.= $row['file'];
-        $output.= ' : <span style="font-weight:bold;">';
-        $output.= $lang['update_disappeared_tn'].'</span><br />';
-      }
-      // suppression de la base :
-      delete_image( $row['id'] );
+      $output.= $row['file'];
+      $output.= ' <span style="font-weight:bold;">';
+      $output.= $lang['update_disappeared'].'</span><br />';
+      $pic_to_delete = true;
+    }
+
+    $thumbnail = $conf['prefix_thumbnail'];
+    $thumbnail.= get_filename_wo_extension( $row['file'] );
+    $thumbnail.= '.'.$row['tn_ext'];
+    if ( !in_array( $thumbnail, $fs_thumbnails ) )
+    {
+      $output.= $row['file'];
+      $output.= ' : <span style="font-weight:bold;">';
+      $output.= $lang['update_disappeared_tn'].'</span><br />';
+      $pic_to_delete = true;
     }
+
+    if ( $pic_to_delete ) delete_image( $row['id'] );
   }
-		
-  // searching the new images in the directory
-  $pictures = array();		
-  $tn_ext = '';
-  if ( $opendir = opendir( $rep ) )
+
+  $registered_pictures = array();
+  $query = 'SELECT file';
+  $query.= ' FROM '.PREFIX_TABLE.'images';
+  $query.= ' WHERE storage_category_id = '.$category_id;
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
+  {
+    array_push( $registered_pictures, $row['file'] );
+  }
+
+  // validated pictures are picture uploaded by users, validated by an admin
+  // and not registered (visible) yet
+  $validated_pictures    = array();
+  $unvalidated_pictures  = array();
+  
+  $query = 'SELECT file,infos,validated';
+  $query.= ' FROM '.PREFIX_TABLE.'waiting';
+  $query.= ' WHERE storage_category_id = '.$category_id;
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
   {
-    while ( $file = readdir( $opendir ) )
+    if ( $row['validated'] == 'true' )
+      $validated_pictures[$row['file']] = $row['infos'];
+    else
+      array_push( $unvalidated_pictures, $row['file'] );
+  }
+
+  // we only search among the picture present in the filesystem and not
+  // present in the database yet. If we know that this picture is known as
+  // an uploaded one but not validated, it's not tested neither
+  $unregistered_pictures = array_diff( $fs_pictures
+                                       ,$registered_pictures
+                                       ,$unvalidated_pictures );
+
+  $inserts = array();
+  
+  foreach ( $unregistered_pictures as $unregistered_picture ) {
+    if ( preg_match( '/^[a-zA-Z0-9-_.]+$/', $unregistered_picture ) )
     {
-      if ( is_file( $rep.'/'.$file ) and is_image( $rep.'/'.$file ) )
+      $file_wo_ext = get_filename_wo_extension( $unregistered_picture );
+      $tn_ext = '';
+      foreach ( $conf['picture_ext'] as $ext ) {
+        $test = $conf['prefix_thumbnail'].$file_wo_ext.'.'.$ext;
+        if ( !in_array( $test, $fs_thumbnails ) ) continue;
+        else { $tn_ext = $ext; break; }
+      }
+      // if we found a thumnbnail corresponding to our picture...
+      if ( $tn_ext != '' )
       {
-        // is the picture waiting for validation by an administrator ?
-        $query = 'SELECT id,validated,infos';
-        $query.= ' FROM '.PREFIX_TABLE.'waiting';
-        $query.= ' WHERE storage_category_id = '.$category_id;
-        $query.= " AND file = '".$file."'";
-        $query.= ';';
-        $result = mysql_query( $query );
-        $waiting = mysql_fetch_array( $result );
-        if (mysql_num_rows( $result ) == 0 or $waiting['validated'] == 'true')
+        $image_size = @getimagesize( $dir.$unregistered_picture );
+        // (file, storage_category_id, date_available, tn_ext, filesize,
+        // width, height, name, author, comment, date_creation)'
+        $value = '(';
+        $value.= "'".$unregistered_picture."'";
+        $value.= ','.$category_id;
+        $value.= ",'".date( 'Y-m-d' )."'";
+        $value.= ",'".$tn_ext."'";
+        $value.= ','.floor( filesize( $dir.$unregistered_picture) / 1024 );
+        $value.= ','.$image_size[0];
+        $value.= ','.$image_size[1];
+        if ( isset( $validated_pictures[$unregistered_picture] ) )
+        {
+          // retrieving infos from the XML description from waiting table
+          $infos = nl2br( $validated_pictures[$unregistered_picture] );
+
+          $unixtime = getAttribute( $infos, 'date_creation' );
+          if ($unixtime != '') $date_creation ="'".date('Y-m-d',$unixtime)."'";
+          else                 $date_creation = 'NULL';
+          
+          $value.= ",'".getAttribute( $infos, 'name' )."'";
+          $value.= ",'".getAttribute( $infos, 'author' )."'";
+          $value.= ",'".getAttribute( $infos, 'comment')."'";
+          $value.= ','.$date_creation;
+
+          // deleting the waiting element
+          $query = 'DELETE FROM '.PREFIX_TABLE.'waiting';
+          $query.= " WHERE file = '".$unregistered_picture."'";
+          $query.= ' AND storage_category_id = '.$category_id;
+          $query.= ';';
+          mysql_query( $query );
+        }
+        else
         {
-          if ( $tn_ext = TN_exists( $rep, $file ) )
-          {
-            // is the picture already in the database ?
-            $query = 'SELECT id';
-            $query.= ' FROM '.PREFIX_TABLE.'images';
-            $query.= ' WHERE storage_category_id = '.$category_id;
-            $query.= " AND file = '".$file."'";
-            $query.= ';';
-            $result = mysql_query( $query );
-            if ( mysql_num_rows( $result ) == 0 )
-            {
-              // the name of the file must not use acentuated characters or
-              // blank space..
-              if ( preg_match( '/^[a-zA-Z0-9-_.]+$/', $file ) )
-              {
-                $picture = array();
-                $picture['file']     = $file;
-                $picture['tn_ext']   = $tn_ext;
-                $picture['date'] = date( 'Y-m-d', filemtime($rep.'/'.$file) );
-                $picture['filesize'] = floor( filesize($rep.'/'.$file) / 1024);
-                $image_size = @getimagesize( $rep.'/'.$file );
-                $picture['width']    = $image_size[0];
-                $picture['height']   = $image_size[1];
-                if ( $waiting['validated'] == 'true' )
-                {
-                  // retrieving infos from the XML description of
-                  // $waiting['infos']
-                  $infos = nl2br( $waiting['infos'] );
-                  $picture['author']        = getAttribute( $infos, 'author' );
-                  $picture['comment']       = getAttribute( $infos, 'comment');
-                  $unixtime = getAttribute( $infos, 'date_creation' );
-                  $picture['date_creation'] = '';
-                  if ( $unixtime != '' )
-                    $picture['date_creation'] = date( 'Y-m-d', $unixtime );
-                  $picture['name']          = getAttribute( $infos, 'name' );
-                  // deleting the waiting element
-                  $query = 'DELETE FROM '.PREFIX_TABLE.'waiting';
-                  $query.= ' WHERE id = '.$waiting['id'];
-                  $query.= ';';
-                  mysql_query( $query );
-                }
-                array_push( $pictures, $picture );
-              }
-              else
-              {
-                $output.= '<span style="color:red;">"'.$file.'" : ';
-                $output.= $lang['update_wrong_dirname'].'</span><br />';
-              }
-
-            }
-          }
-          else
-          {
-            $output.= '<span style="color:red;">';
-            $output.= $lang['update_missing_tn'].' : '.$file;
-            $output.= ' (<span style="font-weight:bold;">';
-            $output.= $conf['prefix_thumbnail'];
-            $output.= get_filename_wo_extension( $file ).'.XXX</span>';
-            $output.= ', XXX = ';
-            $output.= implode( ', ', $conf['picture_ext'] );
-            $output.= ')</span><br />';
-          }
+          $value.= ",'','','',NULL";
         }
+        $value.= ')';
+        
+        $count_new++;
+        $output.= $unregistered_picture;
+        $output.= ' <span style="font-weight:bold;">';
+        $output.= $lang['update_research_added'].'</span>';
+        $output.= ' ('.$lang['update_research_tn_ext'].' '.$tn_ext.')';
+        $output.= '<br />';
+        array_push( $inserts, $value );
       }
+      else
+      {
+        $output.= '<span style="color:red;">';
+        $output.= $lang['update_missing_tn'].' : '.$unregistered_picture;
+        $output.= ' (<span style="font-weight:bold;">';
+        $output.= $conf['prefix_thumbnail'];
+        $output.= get_filename_wo_extension( $unregistered_picture );
+        $output.= '.XXX</span>';
+        $output.= ', XXX = ';
+        $output.= implode( ', ', $conf['picture_ext'] );
+        $output.= ')</span><br />';
+      }
+    }
+    else
+    {
+      $output.= '<span style="color:red;">"'.$unregistered_picture.'" : ';
+      $output.= $lang['update_wrong_dirname'].'</span><br />';
     }
   }
-  // inserting the pictures found in the directory
-  foreach ( $pictures as $picture ) {
+
+  if ( count( $inserts ) > 0 )
+  {
+    // inserts all found pictures
     $query = 'INSERT INTO '.PREFIX_TABLE.'images';
     $query.= ' (file,storage_category_id,date_available,tn_ext';
     $query.= ',filesize,width,height';
     $query.= ',name,author,comment,date_creation)';
     $query.= ' VALUES ';
-    $query.= "('".$picture['file']."','".$category_id."'";
-    $query.= ",'".$picture['date']."','".$picture['tn_ext']."'";
-    $query.= ",'".$picture['filesize']."','".$picture['width']."'";
-    $query.= ",'".$picture['height']."','".$picture['name']."'";
-    $query.= ",'".$picture['author']."','".$picture['comment']."'";
-    if ( $picture['date_creation'] != '' )
-    {
-      $query.= ",'".$picture['date_creation']."'";
-    }
-    else
-    {
-      $query.= ',NULL';
-    }
-    $query.= ');';
+    $query.= implode( ',', $inserts );
+    $query.= ';';
     mysql_query( $query );
-    $count_new++;
-    // retrieving the id of newly inserted picture
+
+    // what are the ids of the pictures in the $category_id ?
+    $ids = array();
+
     $query = 'SELECT id';
     $query.= ' FROM '.PREFIX_TABLE.'images';
     $query.= ' WHERE storage_category_id = '.$category_id;
-    $query.= " AND file = '".$picture['file']."'";
     $query.= ';';
-    list( $image_id ) = mysql_fetch_array( mysql_query( $query ) );
-    // adding the link between this picture and its storage category
-    $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
-    $query.= ' (image_id,category_id) VALUES ';
-    $query.= ' ('.$image_id.','.$category_id.')';
+    $result = mysql_query( $query );
+    while ( $row = mysql_fetch_array( $result ) )
+    {
+      array_push( $ids, $row['id'] );
+    }
+
+    // recreation of the links between this storage category pictures and
+    // its storage category
+    $query = 'DELETE FROM '.PREFIX_TABLE.'image_category';
+    $query.= ' WHERE category_id = '.$category_id;
+    $query.= ' AND image_id IN ('.implode( ',', $ids ).')';
     $query.= ';';
     mysql_query( $query );
 
-    $output.= $picture['file'];
-    $output.= ' <span style="font-weight:bold;">';
-    $output.= $lang['update_research_added'].'</span>';
-    $output.= ' ('.$lang['update_research_tn_ext'].' '.$picture['tn_ext'].')';
-    $output.= '<br />';
+    $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
+    $query.= '(category_id,image_id) VALUES ';
+    foreach ( $ids as $num => $image_id ) {
+      if ( $num > 0 ) $query.= ',';
+      $query.= '('.$category_id.','.$image_id.')';
+    }
+    $query.= ';';
+    mysql_query( $query );
   }
   return $output;
 }
@@ -367,96 +417,131 @@ function remote_images()
 // insert the contained categories if the are not in the database yet. The
 // function also deletes the categories that are in the database and not in
 // the xml_file.
-function insert_remote_category( $xml_dir, $site_id, $id_uppercat, $level )
+function insert_remote_category( $xml_content, $site_id, $id_uppercat, $level )
 {
-  global $conf,$user;
-
+  global $conf, $page, $user, $lang;
+ 
+  $uppercats = '';
   $output = '';
-  $categories = array();
-  $list_dirs = getChildren( $xml_dir, 'dir'.$level );
-  for ( $i = 0; $i < sizeof( $list_dirs ); $i++ )
+  // 0. retrieving informations on the category to display
+  $cat_directory = '../galleries';
+		
+  if ( is_numeric( $id_uppercat ) )
   {
-    // is the category already existing ?
-    $category_id = '';
-    $dir = getAttribute( $list_dirs[$i], 'name' );
-    $categories[$i] = $dir;
+    $query = 'SELECT name,uppercats,dir';
+    $query.= ' FROM '.PREFIX_TABLE.'categories';
+    $query.= ' WHERE id = '.$id_uppercat;
+    $query.= ';';
+    $row = mysql_fetch_array( mysql_query( $query ) );
+    $uppercats = $row['uppercats'];
+    $name      = $row['name'];
 
+    // 1. display the category name to update
     $src = './template/'.$user['template'].'/admin/images/puce.gif';
-    $output.= '<img src="'.$src.'" alt="&gt;" />';
-    $output.= '<span style="font-weight:bold;">'.$dir.'</span>';
+    $output = '<img src="'.$src.'" alt="&gt;" />';
+    $output.= '<span style="font-weight:bold;">'.$name.'</span>';
+    $output.= ' [ '.$row['dir'].' ]';
     $output.= '<div class="retrait">';
 
-    $query = 'SELECT id';
-    $query.= ' FROM '.PREFIX_TABLE.'categories';
-    $query.= ' WHERE site_id = '.$site_id;
-    $query.= " AND dir = '".$dir."'";
-    if ( $id_uppercat == 'NULL' )
-    {
-      $query.= ' AND id_uppercat IS NULL';
-    }
-    else
-    {
-      $query.= ' AND id_uppercat = '.$id_uppercat;
-    }
-    $query.= ';';
-    $result = mysql_query( $query );
-    if ( mysql_num_rows( $result ) == 0 )
-    {
-      $name = str_replace( '_', ' ', $dir );
-      // we have to create the category
-      $query = 'INSERT INTO '.PREFIX_TABLE.'categories';
-      $query.= ' (name,dir,site_id,id_uppercat) VALUES ';
-      $query.= "('".$name."','".$dir."',".$site_id;
-      if ( !is_numeric( $id_uppercat ) )
-      {
-        $query.= ',NULL';
-      }
-      else
-      {
-        $query.= ','.$id_uppercat;
-      }
-      $query.= ');';
-      mysql_query( $query );
-      $category_id = mysql_insert_id();
-    }
-    else
-    {
-      // we get the already registered id
-      $row = mysql_fetch_array( $result );
-      $category_id = $row['id'];
-    }
-    $output.= insert_remote_image( $list_dirs[$i], $category_id );
-    $output.= insert_remote_category( $list_dirs[$i], $site_id,
-                                      $category_id, $level+1 );
-    $output.= '</div>';
+    // 2. we search pictures of the category only if the update is for all
+    //    or a cat_id is specified
+    $output.= insert_remote_image( $xml_content, $id_uppercat );
+  }
+
+  // $xml_dirs contains dir names contained in the xml file for this
+  // id_uppercat
+  $xml_dirs = array();
+  $temp_dirs = getChildren( $xml_content, 'dir'.$level );
+  foreach ( $temp_dirs as $temp_dir ) {
+    array_push( $xml_dirs, getAttribute( $temp_dir, 'name' ) );
   }
-  // we have to remove the categories of the database not present in the xml
-  // file (ie deleted from the picture storage server)
-  $query = 'SELECT dir,id';
+
+  // $database_dirs contains dir names contained in the database for this
+  // id_uppercat and site_id
+  $database_dirs = array();
+  $query = 'SELECT id,dir';
   $query.= ' FROM '.PREFIX_TABLE.'categories';
   $query.= ' WHERE site_id = '.$site_id;
-  if ( !is_numeric( $id_uppercat ) )
+  if (!is_numeric($id_uppercat)) $query.= ' AND id_uppercat IS NULL';
+  else                           $query.= ' AND id_uppercat = '.$id_uppercat;
+  $query.= ' AND dir IS NOT NULL'; // virtual categories not taken
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
   {
-    $query.= ' AND id_uppercat IS NULL';
+    $database_dirs[$row['id']] = $row['dir'];
   }
-  else
+  
+  // 3. we have to remove the categories of the database not present anymore
+  foreach ( $database_dirs as $id => $dir ) {
+    if ( !in_array( $dir, $xml_dirs ) ) delete_category( $id );
+  }
+
+  // array of new categories to insert
+  $inserts = array();
+  
+  foreach ( $xml_dirs as $xml_dir ) {
+    // 5. Is the category already existing ? we create a subcat if not
+    //    existing
+    $category_id = array_search( $xml_dir, $database_dirs );
+    if ( !is_numeric( $category_id ) )
+    {
+      $name = str_replace( '_', ' ', $xml_dir );
+
+      $value = "('".$xml_dir."','".$name."',".$site_id;
+      if ( !is_numeric( $id_uppercat ) ) $value.= ',NULL';
+      else                               $value.= ','.$id_uppercat;
+      $value.= ",'undef'";
+      $value.= ')';
+      array_push( $inserts, $value );
+    }
+  }
+
+  // we have to create the category
+  if ( count( $inserts ) > 0 )
   {
-    $query.= ' AND id_uppercat = '.$id_uppercat;
+    $query = 'INSERT INTO '.PREFIX_TABLE.'categories';
+    $query.= ' (dir,name,site_id,id_uppercat,uppercats) VALUES ';
+    $query.= implode( ',', $inserts );
+    $query.= ';';
+    mysql_query( $query );
+    // updating uppercats field
+    $query = 'UPDATE '.PREFIX_TABLE.'categories';
+    $query.= ' SET uppercats = ';
+    if ( $uppercats != '' ) $query.= "CONCAT('".$uppercats."',',',id)";
+    else                    $query.= 'id';
+    $query.= ' WHERE id_uppercat ';
+    if (!is_numeric($id_uppercat)) $query.= 'IS NULL';
+    else                           $query.= '= '.$id_uppercat;
+    $query.= ';';
+    mysql_query( $query );
   }
+
+  // Recursive call on the sub-categories (not virtual ones)
+  $query = 'SELECT id,dir';
+  $query.= ' FROM '.PREFIX_TABLE.'categories';
+  $query.= ' WHERE site_id = '.$site_id;
+  if (!is_numeric($id_uppercat)) $query.= ' AND id_uppercat IS NULL';
+  else                           $query.= ' AND id_uppercat = '.$id_uppercat;
+  $query.= ' AND dir IS NOT NULL'; // virtual categories not taken
   $query.= ';';
   $result = mysql_query( $query );
   while ( $row = mysql_fetch_array( $result ) )
   {
-    // is the category in the xml file ?
-    if ( !in_array( $row['dir'], $categories ) )
-    {
-      delete_category( $row['id'] );
-    }
+    $database_dirs[$row['dir']] = $row['id'];
   }
+  foreach ( $temp_dirs as $temp_dir ) {
+    $dir = getAttribute( $temp_dir, 'name' );
+    $id_uppercat = $database_dirs[$dir];
+    $output.= insert_remote_category( $temp_dir, $site_id,
+                                      $id_uppercat,$level+1 );
+  }
+
+  if ( is_numeric( $id_uppercat ) ) $output.= '</div>';
 
   return $output;
 }
-	
+
 // insert_remote_image searchs the "root" node of the xml_dir given and
 // insert the contained pictures if the are not in the database yet.
 function insert_remote_image( $xml_dir, $category_id )
@@ -465,101 +550,117 @@ function insert_remote_image( $xml_dir, $category_id )
 
   $output = '';
   $root = getChild( $xml_dir, 'root' );
-  $pictures = array();
+
+  $fs_pictures = array();
   $xml_pictures = getChildren( $root, 'picture' );
-  for ( $j = 0; $j < sizeof( $xml_pictures ); $j++ )
+  foreach ( $xml_pictures as $xml_picture ) {
+    array_push( $fs_pictures, getAttribute( $xml_picture, 'file' ) );
+  }
+  
+  // we have to delete all the images from the database that are not in the
+  // directory anymore (not in the XML anymore)
+  $query = 'SELECT id,file';
+  $query.= ' FROM '.PREFIX_TABLE.'images';
+  $query.= ' WHERE storage_category_id = '.$category_id;
+  $query.= ';';
+  $result = mysql_query( $query );
+  while ( $row = mysql_fetch_array( $result ) )
   {
-    //<picture file="albatros.jpg" tn_ext="png" date="2002-04-14"
-    //  filesize="35" width="640" height="480" />
-    $file     = getAttribute( $xml_pictures[$j], 'file' );
-    $tn_ext   = getAttribute( $xml_pictures[$j], 'tn_ext' );
-    $date     = getAttribute( $xml_pictures[$j], 'date' ); 
-    $filesize = getAttribute( $xml_pictures[$j], 'filesize' );
-    $width    = getAttribute( $xml_pictures[$j], 'width' );
-    $height   = getAttribute( $xml_pictures[$j], 'height' );
-			
-    $pictures[$j] = $file;
-			
-    // is the picture already existing in the database ?
-    $query = 'SELECT id,tn_ext';
-    $query.= ' FROM '.PREFIX_TABLE.'images';
-    $query.= ' WHERE storage_category_id = '.$category_id;
-    $query.= " AND file = '".$file."'";
-    $query.= ';';
-    $result = mysql_query( $query );
-    $query = '';
-    if ( mysql_num_rows( $result ) == 0 )
+    if ( !in_array( $row['file'], $fs_pictures ) )
     {
-      $query = 'INSERT INTO '.PREFIX_TABLE.'images';
-      $query.= ' (file,storage_category_id,date_available,tn_ext';
-      $query.= ',filesize,width,height)';
-      $query.= ' VALUES (';
-      $query.= "'".$file."'";
-      $query.= ",'".$category_id."'";
-      $query.= ",'".$date."'";
-      $query.= ",'".$tn_ext."'";
-      $query.= ",'".$filesize."'";
-      $query.= ",'".$width."'";
-      $query.= ",'".$height."'";
-      $query.= ')';
-      $query.= ';';
-      mysql_query( $query );
-      // retrieving the id of newly inserted picture
-      $query = 'SELECT id';
-      $query.= ' FROM '.PREFIX_TABLE.'images';
-      $query.= ' WHERE storage_category_id = '.$category_id;
-      $query.= " AND file = '".$file."'";
-      $query.= ';';
-      list( $image_id ) = mysql_fetch_array( mysql_query( $query ) );
-      // adding the link between this picture and its storage category
-      $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
-      $query.= ' (image_id,category_id) VALUES ';
-      $query.= ' ('.$image_id.','.$category_id.')';
-      $query.= ';';
-      mysql_query( $query );
-
-      $output.= $file;
+      $output.= $row['file'];
       $output.= ' <span style="font-weight:bold;">';
-      $output.= $lang['update_research_added'].'</span>';
-      $output.= ' ('.$lang['update_research_tn_ext'].' '.$tn_ext.')<br />';
-
-      $count_new++;
-    }
-    else
-    {
-      // is the tn_ext the same in the xml file and in the database ?
-      $row = mysql_fetch_array( $result );
-      if ( $row['tn_ext'] != $tn_ext )
-      {
-        $query = 'UPDATE '.PREFIX_TABLE.'images';
-        $query.= ' SET';
-        $query.= " tn_ext = '".$tn_ext."'";
-        $query.= ' WHERE storage_category_id = '.$category_id;
-        $query.= " AND file = '".$file."'";
-        $query.= ';';
-      }
-    }
-    // execution of the query
-    if ( $query != '' )
-    {
-      mysql_query( $query );
+      $output.= $lang['update_disappeared'].'</span><br />';
+      delete_image( $row['id'] );
     }
   }
-  // we have to remove the pictures of the database not present in the xml file
-  // (ie deleted from the picture storage server)
-  $query = 'SELECT id,file';
+
+  $database_pictures = array();
+  $query = 'SELECT file';
   $query.= ' FROM '.PREFIX_TABLE.'images';
   $query.= ' WHERE storage_category_id = '.$category_id;
   $query.= ';';
   $result = mysql_query( $query );
   while ( $row = mysql_fetch_array( $result ) )
   {
-    // is the file in the xml file ?
-    if ( !in_array( $row['file'], $pictures ) )
+    array_push( $database_pictures, $row['file'] );
+  }
+
+  $inserts = array();
+  $xml_pictures = getChildren( $root, 'picture' );
+  foreach ( $xml_pictures as $xml_picture ) {
+    // <picture file="albatros.jpg" tn_ext="png" filesize="35" width="640"
+    // height="480" />
+    $file = getAttribute( $xml_picture, 'file' );
+
+    // is the picture already existing in the database ?
+    if ( !in_array( $file, $database_pictures ) )
     {
-      delete_image( $row['id'] );
+      $tn_ext = getAttribute( $xml_picture, 'tn_ext' );
+      // (file, storage_category_id, date_available, tn_ext, filesize,
+      // width, height)
+      $value = '(';
+      $value.= "'".$file."'";
+      $value.= ','.$category_id;
+      $value.= ",'".date( 'Y-m-d' )."'";
+      $value.= ",'".$tn_ext."'";
+      $value.= ','.getAttribute( $xml_picture, 'filesize' );
+      $value.= ','.getAttribute( $xml_picture, 'width' );
+      $value.= ','.getAttribute( $xml_picture, 'height' );
+      $value.= ')';
+
+      $count_new++;
+      $output.= $file;
+      $output.= ' <span style="font-weight:bold;">';
+      $output.= $lang['update_research_added'].'</span>';
+      $output.= ' ('.$lang['update_research_tn_ext'].' '.$tn_ext.')';
+      $output.= '<br />';
+      array_push( $inserts, $value );
+    }
+  }
+
+  if ( count( $inserts ) > 0 )
+  {
+    // inserts all found pictures
+    $query = 'INSERT INTO '.PREFIX_TABLE.'images';
+    $query.= ' (file,storage_category_id,date_available,tn_ext';
+    $query.= ',filesize,width,height)';
+    $query.= ' VALUES ';
+    $query.= implode( ',', $inserts );
+    $query.= ';';
+    mysql_query( $query );
+
+    // what are the ids of the pictures in the $category_id ?
+    $ids = array();
+
+    $query = 'SELECT id';
+    $query.= ' FROM '.PREFIX_TABLE.'images';
+    $query.= ' WHERE storage_category_id = '.$category_id;
+    $query.= ';';
+    $result = mysql_query( $query );
+    while ( $row = mysql_fetch_array( $result ) )
+    {
+      array_push( $ids, $row['id'] );
+    }
+
+    // recreation of the links between this storage category pictures and
+    // its storage category
+    $query = 'DELETE FROM '.PREFIX_TABLE.'image_category';
+    $query.= ' WHERE category_id = '.$category_id;
+    $query.= ' AND image_id IN ('.implode( ',', $ids ).')';
+    $query.= ';';
+    mysql_query( $query );
+
+    $query = 'INSERT INTO '.PREFIX_TABLE.'image_category';
+    $query.= '(category_id,image_id) VALUES ';
+    foreach ( $ids as $num => $image_id ) {
+      if ( $num > 0 ) $query.= ',';
+      $query.= '('.$category_id.','.$image_id.')';
     }
+    $query.= ';';
+    mysql_query( $query );
   }
+
   return $output;
 }
 //----------------------------------------------------- template initialization
@@ -569,15 +670,9 @@ $tpl = array( 'update_default_title', 'update_only_cat', 'update_all',
               'remote_site', 'update_part_research' );
 templatize_array( $tpl, 'lang', $sub );
 $vtp->setGlobalVar( $sub, 'user_template', $user['template'] );
-//-------------------------------------------------------- categories structure
-$page['plain_structure'] = get_plain_structure();
 //-------------------------------------------- introduction : choices of update
 // Display choice if "update" var is not specified
-check_cat_id( $_GET['update'] );
-if ( !isset( $_GET['update'] )
-     and !( isset( $page['cat'] )
-            or $_GET['update'] == 'cats'
-            or $_GET['update'] == 'all' ) )
+if (!isset( $_GET['update'] ))
 {
   $vtp->addSession( $sub, 'introduction' );
   // only update the categories, not the pictures.
@@ -591,6 +686,8 @@ if ( !isset( $_GET['update'] )
 //-------------------------------------------------- local update : ./galleries
 else
 {
+  check_cat_id( $_GET['update'] );
+  $start = get_moment();
   $count_new = 0;
   $count_deleted = 0;
   $vtp->addSession( $sub, 'local_update' );
@@ -602,6 +699,8 @@ else
   {
     $categories = insert_local_category( 'NULL' );
   }
+  $end = get_moment();
+  echo get_elapsed_time( $start, $end ).' for update <br />';
   $vtp->setVar( $sub, 'local_update.categories', $categories );
   $vtp->setVar( $sub, 'local_update.count_new', $count_new );
   $vtp->setVar( $sub, 'local_update.count_deleted', $count_deleted );
@@ -613,15 +712,32 @@ if ( @is_file( './listing.xml' ) )
   $count_new = 0;
   $count_deleted = 0;
   $vtp->addSession( $sub, 'remote_update' );
-
+  
+  $start = get_moment();
   remote_images();
+  $end = get_moment();
+  echo get_elapsed_time( $start, $end ).' for remote_images<br />';
+  
   $vtp->setVar( $sub, 'remote_update.count_new', $count_new );
   $vtp->setVar( $sub, 'remote_update.count_deleted', $count_deleted );
 
   $vtp->closeSession( $sub, 'remote_update' );
 }
 //---------------------------------------- update informations about categories
-update_category( 'all' );
+if ( isset( $_GET['update'] )
+     or isset( $page['cat'] )
+     or @is_file( './listing.xml' ) )
+{
+  $start = get_moment();
+  update_category( 'all' );
+  $end = get_moment();
+  echo get_elapsed_time( $start, $end ).' for update_category( all )<br />';
+
+  $start = get_moment();
+  synchronize_all_users();
+  $end = get_moment();
+  echo get_elapsed_time( $start, $end ).' for synchronize_all_users<br />';
+}
 //----------------------------------------------------------- sending html code
 $vtp->Parse( $handle , 'sub', $sub );
 ?>
\ No newline at end of file
diff --git a/admin/user_list.php b/admin/user_list.php
index e8b6bb34b..a80d73c3e 100644
--- a/admin/user_list.php
+++ b/admin/user_list.php
@@ -58,7 +58,7 @@ if ( isset ( $_GET['delete'] ) and is_numeric( $_GET['delete'] ) )
   $query.= ';';
   $row = mysql_fetch_array( mysql_query( $query ) );
   // confirm user deletion ?
-  if ( $_GET['confirm'] != 1 )
+  if ( !isset( $_GET['confirm'] ) )
   {
     $vtp->addSession( $sub, 'deletion' );
     $vtp->setVar( $sub, 'deletion.login', $row['username'] );
@@ -109,7 +109,8 @@ else
   $vtp->addSession( $sub, 'add_user' );
   $action = './admin.php?'.$_SERVER['QUERY_STRING'];
   $vtp->setVar( $sub, 'add_user.form_action', $action );
-  $vtp->setVar( $sub, 'add_user.f_username', $_POST['username'] );
+  if (isset( $_POST['username']))
+	  $vtp->setVar( $sub, 'add_user.f_username', $_POST['username'] );
   $vtp->closeSession( $sub, 'add_user' );
   
   $vtp->addSession( $sub, 'users' );
@@ -149,7 +150,7 @@ else
     }
     $vtp->addSession( $sub, 'user' );
     // checkbox for mail management if the user has a mail address
-    if ( $row['mail_address'] != '' and $row['username'] != 'guest' )
+    if ( isset( $row['mail_address'] ) and $row['username'] != 'guest' )
     {
       $vtp->addSession( $sub, 'checkbox' );
       $vtp->setVar( $sub, 'checkbox.name', 'mail-'.$row['id'] );
@@ -229,7 +230,7 @@ else
     $result = mysql_query( $query );
     while ( $row = mysql_fetch_array( $result ) )
     {
-      if ( $_POST['mail-'.$row['id']] == 1 )
+      if ( isset( $_POST['mail-'.$row['id']] ) )
         array_push( $mails, $row['mail_address'] );
     }
     $mail_destination = '';
diff --git a/admin/user_modify.php b/admin/user_modify.php
index e49d3b3b0..cc6486c7a 100644
--- a/admin/user_modify.php
+++ b/admin/user_modify.php
@@ -39,6 +39,7 @@ $query.= ';';
 $row = mysql_fetch_array( mysql_query( $query ) );
 $page['username'] = $row['username'];
 $page['status'] = $row['status'];
+if ( !isset( $row['mail_address'] ) ) $row['mail_address'] = '';
 $page['mail_address'] = $row['mail_address'];
 // user is not modifiable if :
 //   1. the selected user is the user "guest"
@@ -62,10 +63,7 @@ if ( sizeof( $error ) == 0 and isset( $_POST['submit'] ) )
 {
   // shall we use a new password and overwrite the old one ?
   $use_new_password = false;
-  if ( $_POST['use_new_pwd'] == 1)
-  {
-    $use_new_password = true;
-  }
+  if ( isset( $_POST['use_new_pwd'] ) ) $use_new_password = true;
   // if we try to update the webmaster infos, we have to set the status to
   // 'admin'
   if ( $row['username'] == $conf['webmaster'] )
@@ -88,7 +86,7 @@ if ( isset( $_POST['submit'] ) )
   while ( $row = mysql_fetch_array( $result ) )
   {
     $dissociate = 'dissociate-'.$row['id'];
-    if ( $_POST[$dissociate] == 1 )
+    if ( isset( $_POST[$dissociate] ) )
     {
       $query = 'DELETE FROM '.PREFIX_TABLE.'user_group';
       $query.= ' WHERE user_id = '.$_GET['user_id'];
@@ -103,6 +101,8 @@ if ( isset( $_POST['submit'] ) )
   $query.= ' ('.$_GET['user_id'].','.$_POST['associate'].')';
   $query.= ';';
   mysql_query( $query );
+  // synchronize category informations for this user
+  synchronize_user( $_GET['user_id'] );
 }
 //-------------------------------------------------------------- errors display
 if ( sizeof( $error ) != 0 )
@@ -124,7 +124,7 @@ if ( sizeof( $error ) == 0 and isset( $_POST['submit'] ) )
   $url = add_session_id( './admin.php?page=user_list' );
   $vtp->setVar( $sub, 'confirmation.url', $url );
   $vtp->closeSession( $sub, 'confirmation' );
-  if ( $use_new_pwd )
+  if ( $use_new_password )
   {
     $vtp->addSession( $sub, 'password_updated' );
     $vtp->closeSession( $sub, 'password_updated' );
diff --git a/admin/user_perm.php b/admin/user_perm.php
index d272552ae..19f7e4b6f 100644
--- a/admin/user_perm.php
+++ b/admin/user_perm.php
@@ -52,13 +52,14 @@ if ( isset( $_POST['submit'] ) )
     }
   }
   check_favorites( $_GET['user_id'] );
+  synchronize_user( $_GET['user_id'] );
   $vtp->addSession( $sub, 'confirmation' );
   $url = './admin.php?page=user_list';
   $vtp->setVar( $sub, 'confirmation.back_url', add_session_id( $url ) );
   $vtp->closeSession( $sub, 'confirmation' );
 }
 //---------------------------------------------------------------- form display
-$restrictions = get_restrictions( $_GET['user_id'], $page['user_status'],
+$restrictions = get_user_restrictions( $_GET['user_id'], $page['user_status'],
                                   false, false );
 $action = './admin.php?page=user_perm&amp;user_id='.$_GET['user_id'];
 $vtp->setVar( $sub, 'action', add_session_id( $action ) );
diff --git a/admin/waiting.php b/admin/waiting.php
index aefb6e9d8..5fc79303e 100644
--- a/admin/waiting.php
+++ b/admin/waiting.php
@@ -116,7 +116,7 @@ while ( $row = mysql_fetch_array( $result ) )
   // file name
   $vtp->setVar( $sub, 'picture.file', $row['file'] );
   // is there an existing associated thumnail ?
-  if ( $row['tn_ext'] != '' )
+  if ( isset( $row['tn_ext'] ) and $row['tn_ext'] != '' )
   {
     $vtp->addSession( $sub, 'thumbnail' );
     $thumbnail = $conf['prefix_thumbnail'];