<?php

/**
 * Implementation of hook_node_widget_form_alter()
 */
function taxonomy_node_widget_form_alter(&$form, &$form_state, $form_id) {
  if (isset($form['type']) && isset($form['#node']) && $form['type']['#value'] .'_node_widget_form' == $form_id) {

    $vocabs = taxonomy_get_vocabularies($form['type']['#value']);
    $blank = array();
    $extra = array();
    $extra['form_id']['#value'] = $form['type']['#value']. '_node_form';
    $extra['type'] = $form['type'];
    $extra['#node'] = $form['#node'];
    taxonomy_form_alter(&$extra, &$blank, $form['type']['#value']. '_node_form');
    $count = count($vocabs);
    if ($count > 0) {
      foreach ($vocabs as $vid => $taxonomy) {
        if (isset($form_state['#node_widget_settings']['taxonomy_'. $vid]) && !$form_state['#node_widget_settings']['taxonomy_'. $vid]) {
          unset($extra['taxonomy'][$vid]);
        }
      }
    }

    // Remove fieldset
    unset($extra['taxonomy']['#type']);
    unset($extra['taxonomy']['#title']);
    unset($extra['taxonomy']['#collapsible']);
    unset($extra['taxonomy']['#collapsed']);

    $form['taxonomy'] = $extra['taxonomy'];
  }
}

/**
 * Implementation of hook_node_widget_widget_settings()
 */
function taxonomy_node_widget_widget_settings($type) {
  $settings = array();

  $vocabs = taxonomy_get_vocabularies($type->type);

  foreach ($vocabs as $vid => $taxonomy) {
      $settings[] = array(
          'name' => 'taxonomy_'. $vid,
          'label' => $taxonomy->name,
          'supported' => TRUE,
          'message' => NULL,
      );
  }

  return $settings;
}

/**
 * Implementation of hook_node_widget_is_empty()
 */
function taxonomy_node_widget_is_empty($form, $form_state) {
    // TODO
    return FALSE;
}