source: extensions/user_tags/include/t4u_content.class.php

<?php
// +-----------------------------------------------------------------------+
// | User Tags  - a plugin for Piwigo                                      |
// +-----------------------------------------------------------------------+
// | Copyright(C) 2010-2013 Nicolas Roudaire        http://www.nikrou.net  |
// +-----------------------------------------------------------------------+
// | This program is free software; you can redistribute it and/or modify  |
// | it under the terms of the GNU General Public License version 2 as     |
// | published by the Free Software Foundation                             |
// |                                                                       |
// | This program is distributed in the hope that it will be useful, but   |
// | WITHOUT ANY WARRANTY; without even the implied warranty of            |
// | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      |
// | General Public License for more details.                              |
// |                                                                       |
// | You should have received a copy of the GNU General Public License     |
// | along with this program; if not, write to the Free Software           |
// | Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,            |
// | MA 02110-1301 USA.                                                    |
// +-----------------------------------------------------------------------+

class t4u_Content
{
  public function __construct($config) {
    $this->plugin_config = &$config;
  }

  public function render_element_content($content, $picture) {
    global $template;

    $template->set_prefilter('picture', array(__CLASS__, 'picture_prefilter'));

    if ($this->plugin_config->hasPermission('add')) {
      load_language('plugin.lang', T4U_PLUGIN_LANG);

      $template->assign('T4U_JS', T4U_JS);
      $template->assign('T4U_CSS', T4U_CSS);
      $template->assign('T4U_IMGS', T4U_IMGS);
      $template->assign('T4U_PERMISSION_DELETE', $this->plugin_config->hasPermission('delete'));
      $template->assign('T4U_UPDATE_SCRIPT', get_root_url().'ws.php?format=json&method='.T4U_WS.'update');
      $template->assign('T4U_UPDATE_METHOD', T4U_WS.'update');
      $template->assign('T4U_LIST_SCRIPT', get_root_url().'ws.php?format=json&method='.T4U_WS.'list');
      $template->assign('T4U_IMAGE_ID', $picture['id']);
      $template->assign('T4U_REFERER', urlencode($picture['url']));
      $template->assign('T4U_PERMISSION_DELETE', $this->plugin_config->hasPermission('delete'));
      if ($this->plugin_config->hasPermission('existing_tags_only')) {
        $template->assign('T4U_ALLOW_CREATION', 'false');
      } else {
        $template->assign('T4U_ALLOW_CREATION', 'true');
      }
      
      $related_tags = array();
      $_tpl_vars = $template->get_template_vars('related_tags');
      if (!empty($_tpl_vars)) {
        foreach ($_tpl_vars as $id => $tag_infos) {
          $related_tags['~~'.$tag_infos['id'].'~~'] = $tag_infos['name']; 
        }
        $template->assign('T4U_RELATED_TAGS', $related_tags);
      }

      $template->set_filename('add_tags', T4U_TEMPLATE.'/add_tags.tpl');
      $template->assign_var_from_handle('PLUGIN_PICTURE_AFTER', 'add_tags');
    }

    return $content;
  }

  public static function picture_prefilter($source, $smarty) {
    $pattern = '{if $display_info.tags and isset($related_tags)}';
    $replace = '{if $display_info.tags}';
    
    return str_replace($pattern, $replace, $source);
  }
}