/**
 * Implementation of a Drupal action.
 * Changes node type.
 */
function action_nodetype_node_change_type($op, $edit = array(), &$node) {
  switch($op) {
    case 'metadata':
      return array(
        'description' => t('Change node type'),
        'type' => t('Node'),
        'batchable' => true,
        'configurable' => true,
      );

    case 'do':
      $types = node_get_types();
      $node->type = $edit['nodetype'];
      $node->revision = '0';
      node_save($node);
      if ($edit['showmsg']) {
        drupal_set_message(t('The node type of post %title has been changed from %old to %new.', array('%title' => $node->title, '%old' => $types[$node->type]->name, '%new' => $types[$edit['nodetype']]->name)));
      }
      break;

    case 'form':
      $form = array();
      $types = node_get_types('names');
      $form['nodetype'] = array(
          '#type' => 'select',
          '#title' => t('Node type'),
	      '#options' => $types,
          '#default_value' => 0,
      );
      $form['showmsg'] = array(
	      '#type' => 'select',
	      '#title' => t('Display system message on change?'),
     	  '#options' => array(0 => 'No', 1 => 'Yes'),
          '#default_value' => 0,
	  );
      return $form;

    case 'validate':
      return TRUE;

    case 'submit':
      $params = array('nodetype' => $edit['nodetype'], 'showmsg' => $edit['showmsg']);
      return $params;
  }
}