root/extensions/pwgCumulus/include/pwgCumulusConfig.class.php

<?php
// +-----------------------------------------------------------------------+
// | pwgCumulus  - a plugin for Piwigo                                     |
// +-----------------------------------------------------------------------+
// | Copyright(C) 2009-2011 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 pwgCumulusConfig
{
  private 
    $config = array(), 
    $plugin_dir;

  public function __construct($plugin_dir, $plugin_name) {
    $this->plugin_dir = $plugin_dir;
    $this->plugin_name = $plugin_name;

    if (!file_exists($this->get_config_file_dir())) {
      mkgetdir($this->get_config_file_dir());
    }

    if (!file_exists($this->get_config_filename())) {
      $this->setDefaults();
      $this->save_config();
    }
  }

  public function load_config() {
    $x = file_get_contents($this->get_config_filename());
    if ($x!==false) {
      $c = unserialize($x);
      $this->config = $c;
    }
  }

  public function save_config() {
    file_put_contents($this->get_config_filename(), serialize($this->config));
  }

  private function get_config_file_dir() {
    return $GLOBALS['conf']['local_data_dir'].'/plugins/';
  }

  private function get_config_filename() {
    return $this->get_config_file_dir().basename($this->plugin_dir).'.dat';
  }

  public function __set($key, $value) {
    // need filters ??
    $this->config[$key] = $value;
  }

  public function __get($key) {
    return isset($this->config[$key])?$this->config[$key]:null;
  }

  public function plugin_admin_menu($menu) {
    array_push($menu,
               array('NAME' => $this->plugin_name,
                     'URL' => get_admin_plugin_menu_link($this->plugin_dir.'/admin.php')                 
                     )
               );
    return $menu;
  }

  private function setDefaults() {
    include $this->plugin_dir.'/default_values.inc.php';

    foreach ($default_values as $key => $value) {
      if (empty($this->config[$key])) {
        $this->config[$key] = $value;
      }
    }
  }
}
?>