<?PHP
  require_once('core/xmlparser.inc.php');
  require_once('core/db.inc.php');
  
  function Uses() {
    foreach(func_get_args() as $file) {
      if(isset($GLOBALS['modules']->code[$file]))
        require_once($GLOBALS['modules']->GetCodePath($file));
      else
        die('Fatal: a required code file was not found.');
    }
  }
  
  class Modules {
    var $modules = array();
    var $pages = array();
    var $code = array();
    var $templates = array();
    
    function Modules() {
      $module = $this->Load('base.xml');
      if(!$module) die('Fatal: could not load Neon base.');
      
      $module['path'] = '';
      
      $this->modules['base'] = $module;
      
      
      $dir = opendir('modules');
      
      while($moddir = readdir($dir)) {
        if($moddir[0] == '.' || !is_dir('modules/' . $moddir) || !is_file('modules/' . $moddir . '/module.xml'))
          continue;
        
        $module = $this->Load('modules/' . $moddir . '/module.xml');
        
        if(!$module) continue;
        
        $module['path'] = 'modules/' . $moddir . '/';
        $this->modules[$module['name']] = $module;
      }
      
      closedir($dir);
      
      $res = $GLOBALS['db']->Execute('SELECT name, enabled FROM modules');
      
      $row[0] = 'base';
      $row[1] = 1;
      
      do {
        if(!array_key_exists($row[0], $this->modules)) {
          $GLOBALS['db']->Execute('DELETE FROM modules WHERE name = ?', $row[0]);
          continue;
        }
        
        if(!$row[1]) continue;
        
        $this->modules[$row[0]]['enabled'] = true;
        
        foreach($this->modules[$row[0]]['pages'] as $page)
          $this->pages[$page] = &$this->modules[$row[0]];
        foreach($this->modules[$row[0]]['code'] as $code)
          $this->code[$code] = &$this->modules[$row[0]];
        foreach($this->modules[$row[0]]['templates'] as $template)
          $this->templates[$template] = &$this->modules[$row[0]];
      } while($row = $res->FetchRow());
    }
    
    function Load($file) {
      if(!is_file($file)) return null;
      
      $data = $GLOBALS['xmlparser']->ParseFile($file);
      if(!$data) return null;
      
      $info = $GLOBALS['xmlparser']->FindTag($data, 'info');
      if(!$info) return null;
      
      $name = $GLOBALS['xmlparser']->FindTag($info, 'name');
      if(!$name) return null;
      if(count($name['children']) != 1) return null;
      if(!is_string($name['children'][0])) return null;
      $name = $name['children'][0];
      
      $version = $GLOBALS['xmlparser']->FindTag($info, 'version');
      if(!$version) return null;
      if(count($version['children']) != 1) return null;
      if(!is_string($version['children'][0])) return null;
      $version = $version['children'][0];
      
      $desc = $GLOBALS['xmlparser']->FindTag($info, 'desc');
      if($desc && (count($desc['children']) == 1) && is_string($desc['children'][0])) $desc = $desc['children'][0];
      else $desc = '';
      
      
      $module = array('name' => $name, 'version' => $version, 'desc' => $desc, 'code' => array(),
                      'pages' => array(), 'templates' => array(), 'config' => false, 'enabled' => false);
      
      if($GLOBALS['xmlparser']->FindTag($info, 'config')) $module['config'] = true;
      
      $files = $GLOBALS['xmlparser']->FindTag($data, 'files');
      if(!$files) return $module;
      
      foreach($files['children'] as $file) {
        if(!is_array($file)) continue;
        if(count($file['children']) != 1) continue;
        if(!is_string($file['children'][0])) continue;
        
        switch($file['tag']) {
          case 'page':
            $type = $file['attribs']['type'];
            if(!$type) $type = 'c';
            
            array_push($module['pages'], $file['children'][0] . '.' . $type);
            break;
          case 'code':
            array_push($module['code'], $file['children'][0]);
            break;
          case 'template':
            array_push($module['templates'], $file['children'][0]);
        }
      }
      
      return $module;
    }
    
    function GetCodePath($name) {
      return $this->code[$name]['path'] . 'code/' . $name . '.inc.php';
    }
    
    function GetPagePath($name, $type) {
      return $this->pages[$name . '.' . $type]['path'] . 'pages/' .
             strtr($type, array('c' => 'content', 'e' => 'editor', 'n' => 'nav', 'b' => 'base')) . '/' . $name . '.xml';
    }
    
    function GetTemplatePath($name) {
      return $this->templates[$name]['path'] . 'templates/' . $name . '.inc.php';
    }
    
    function Exists($name) {
      return array_key_exists($name, $this->modules);
    }
    
    function Enabled($name) {
      return $this->Exists($name) && $this->modules[$name]['enabled'];
    }
    
    function HasConfig($name) {
      if(!$this->Exists($name)) return false;
      
      return $this->modules[$name]['config'];
    }
    
    function Enable($name, $enable = true) {
      if(!$this->Exists($name)) return false;
      
      if($this->Enabled($name) == $enable) return true;
      
      $res = $GLOBALS['db']->Execute('SELECT id FROM modules WHERE name = ?', $name);
      
      if($res->RecordCount()) {
        $GLOBALS['db']->Execute('UPDATE modules SET enabled = ? WHERE name = ?', array(intval($enable), $name));
      
        return ($GLOBALS['db']->Affected_Rows() > 0);
      }
      
      $GLOBALS['db']->Execute('INSERT INTO modules (name, enabled) VALUES (?, ?)', array($name, intval($enable)));
      
      return ($GLOBALS['db']->Affected_Rows() > 0);
    }
    
    function Disable($name) {
      return $this->Enable($name, false);
    }
  }
  
  $GLOBALS['modules'] = new Modules;
?>