<?php

/**
 * @file
 * Fieldgroup module.
 *
 * For an overview of all php and javascript hooks, see field_group.api.php.
 *
 */

/**
 * Implements hook_menu().
 */
function field_group_menu() {
  $items = array();

  // Ensure the following is not executed until field_bundles is working and
  // tables are updated. Needed to avoid errors on initial installation.
  if (defined('MAINTENANCE_MODE')) {
    return $items;
  }

  // Create tabs for all possible bundles.
  foreach (entity_get_info() as $entity_type => $entity_info) {
    if (isset($entity_info['fieldable']) && $entity_info['fieldable']) {
      foreach ($entity_info['bundles'] as $bundle_name => $bundle_info) {
        if (isset($bundle_info['admin'])) {
          // Extract path information from the bundle.
          $path = $bundle_info['admin']['path'];
          // Different bundles can appear on the same path (e.g. %node_type and
          // %comment_node_type). To allow field_group_menu_load() to extract the
          // actual bundle object from the translated menu router path
          // arguments, we need to identify the argument position of the bundle
          // name string ('bundle argument') and pass that position to the menu
          // loader. The position needs to be casted into a string; otherwise it
          // would be replaced with the bundle name string.
          if (isset($bundle_info['admin']['bundle argument'])) {
            $bundle_arg = $bundle_info['admin']['bundle argument'];
            $bundle_pos = (string) $bundle_arg;
          }
          else {
            $bundle_arg = $bundle_name;
            $bundle_pos = '0';
          }

          // This is the position of the %field_group_menu placeholder in the
          // items below.
          $group_position = count(explode('/', $path)) + 1;

          // Extract access information, providing defaults.
          $access = array_intersect_key($bundle_info['admin'], drupal_map_assoc(array('access callback', 'access arguments')));
          $access += array(
            'access callback' => 'user_access',
            'access arguments' => array('administer site configuration'),
          );

          $items["$path/groups/%field_group_menu/delete"] = array(
            'load arguments' => array($entity_type, $bundle_arg, $bundle_pos, '%map'),
            'title' => 'Delete',
            'page callback' => 'drupal_get_form',
            'page arguments' => array('field_group_delete_form', $group_position),
            'type' => MENU_CALLBACK,
            'file' => 'field_group.field_ui.inc',
          ) + $access;
        }
      }
    }
  }

  return $items;
}

/**
 * Implements hook_permission().
 */
function field_group_permission() {
  return array(
    'administer fieldgroups' => array(
      'title' => t('Administer fieldgroups'),
      'description' => t('Display the administration for fieldgroups.'),
    ),
  );
}

/**
 * Menu Wildcard loader function to load group definitions.
 *
 * @param $group_name
 *   The name of the group, as contained in the path.
 * @param $entity_type
 *   The name of the entity.
 * @param $bundle_name
 *   The name of the bundle, as contained in the path.
 * @param $bundle_pos
 *   The position of $bundle_name in $map.
 * @param $map
 *   The translated menu router path argument map.
 */
function field_group_menu_load($group_name, $entity_type, $bundle_name, $bundle_pos, $map) {

  if ($bundle_pos > 0) {
    $bundle = $map[$bundle_pos];
    $bundle_name = field_extract_bundle($entity_type, $bundle);
  }

  $args = func_get_args();
  $args_pop = array_pop($args);
  $mode = array_pop($args_pop);

  return field_group_load_field_group($group_name, $entity_type, $bundle_name, $mode);
}

/**
 * Loads a group definition.
 *
 * @param $group_name
 *   The name of the group.
 * @param $entity_type
 *   The name of the entity.
 * @param $bundle_name
 *   The name of the bundle.
 * @param $mode
 *   The view mode to load.
 */
function field_group_load_field_group($group_name, $entity_type, $bundle_name, $mode) {

  ctools_include('export');
  $objects = ctools_export_load_object('field_group', 'conditions', array(
    'group_name' => $group_name,
    'entity_type' => $entity_type,
    'bundle' => $bundle_name,
    'mode' => $mode,
  ));
  $object = array_shift($objects);

  if ($object && isset($object->data)) {
    return field_group_unpack($object);
  }

  return $object;
}

/**
 * Implements hook_ctools_plugin_api().
 */
function field_group_ctools_plugin_api($owner, $api) {
  if ($owner == 'field_group' && $api == 'field_group') {
    return array('version' => 1);
  }
}

/**
 * Implements hook_theme().
 */
function field_group_theme() {
  return array(
    'multipage' => array(
      'render element' => 'element',
    ),
    'multipage_pane' => array(
      'render element' => 'element',
    ),
  );
}

/**
 * Implements hook_theme_registry_alter().
 */
function field_group_theme_registry_alter(&$theme_registry) {

  // Inject field_group_build_entity_groups in all entity theming functions.
  $entity_info = entity_get_info();
  $entities = array();
  foreach ($entity_info as $entity => $info) {
    if (isset($entity_info[$entity]['fieldable']) && $entity_info[$entity]['fieldable']) {
      // User uses user_profile for theming.
      if ($entity == 'user') $entity = 'user_profile';
      $entities[] = $entity;
    }
  }

  // Support for File Entity.
  if (isset($theme_registry['file_entity'])) {
    $entities[] = 'file_entity';
  }

  // Support for Entity API.
  if (isset($theme_registry['entity'])) {
    $entities[] = 'entity';
  }

  foreach ($entities as $entity) {
    if (isset($theme_registry[$entity])) {
      $theme_registry[$entity]['preprocess functions'][] = 'field_group_build_entity_groups';
      // DS support, make sure it comes after field_group.
      if ($key = array_search('ds_entity_variables', $theme_registry[$entity]['preprocess functions'])) {
        unset($theme_registry[$entity]['preprocess functions'][$key]);
        $theme_registry[$entity]['preprocess functions'][] = 'ds_entity_variables';
      }
    }
  }

}

/**
 * Implements hook_field_attach_delete_bundle().
 *
 * @param String $entity_type
 * @param String $bundle
 */
function field_group_field_attach_delete_bundle($entity_type, $bundle) {

  ctools_include('export');
  $list = field_group_read_groups(array('bundle' => $bundle, 'entity_type' => $entity_type));

  // Delete the entity's entry from field_group of all entities.
  // We fetch the field groups first to assign the removal task to ctools.
  if (isset($list[$entity_type], $list[$entity_type][$bundle])) {
    foreach ($list[$entity_type][$bundle] as $group_mode => $groups) {
      foreach ($groups as $group) {
        ctools_export_crud_delete('field_group', $group);
      }
    }
  }

}

/**
 * Implements hook_field_attach_form().
 */
function field_group_field_attach_form($entity_type, $entity, &$form, &$form_state, $langcode) {
  $form['#attached']['css'][] = drupal_get_path('module', 'field_group') . '/field_group.field_ui.css';
  field_group_attach_groups($form, 'form', $form_state);
  $form['#pre_render'][] = 'field_group_form_pre_render';
}

/**
 * Implements hook_form_FORM_ID_alter().
 * Using hook_form_field_ui_field_overview_form_alter.
 */
function field_group_form_field_ui_field_overview_form_alter(&$form, &$form_state) {
  form_load_include($form_state, 'inc', 'field_group', 'field_group.field_ui');
  field_group_field_ui_overview_form_alter($form, $form_state);
}

/**
 * Implements hook_form_FORM_ID_alter().
 * Using hook_form_field_ui_display_overview_form_alter.
 */
function field_group_form_field_ui_display_overview_form_alter(&$form, &$form_state) {
  form_load_include($form_state, 'inc', 'field_group', 'field_group.field_ui');
  field_group_field_ui_overview_form_alter($form, $form_state, TRUE);
}

/**
 * Implements hook_field_attach_view_alter().
 */
function field_group_field_attach_view_alter(&$element, $context) {
  // Check whether the view mode uses custom display settings or the 'default' mode.
  $actual_mode = 'default';
  if (isset($element['#entity_type']) && isset($element['#bundle'])) {
    $view_mode_settings = field_view_mode_settings($element['#entity_type'], $element['#bundle']);
    $view_mode = $context['view_mode'];
    $actual_mode = (!empty($view_mode_settings[$view_mode]['custom_settings']) ? $view_mode : 'default');
    field_group_attach_groups($element, $actual_mode);
  }
}

/**
 * Implements hook_field_group_formatter_info().
 */
function field_group_field_group_formatter_info() {

  $info = array(
    'form' => array(
      'div' => array(
        'label' => t('Div'),
        'description' => t('This fieldgroup renders the inner content in a simple div with the title as legend.'),
        'format_types' => array('open', 'collapsible', 'collapsed'),
        'instance_settings' => array('description' => '', 'show_label' => 1, 'label_element' => 'h3', 'effect' => 'none', 'speed' => 'fast', 'classes' => '', 'required_fields' => 1, 'id' => ''),
        'default_formatter' => 'open',
      ),
      'html5' => array(
        'label' => t('HTML5'),
        'description' => t('This fieldgroup renders the inner content in a semantic HTML5 wrapper'),
        'instance_settings' => array('wrapper' => '', 'classes' => ''),
      ),
      'fieldset' => array(
        'label' => t('Fieldset'),
        'description' => t('This fieldgroup renders the inner content in a fieldset with the title as legend.'),
        'format_types' => array('open', 'collapsible', 'collapsed'),
        'instance_settings' => array('description' => '', 'classes' => '', 'required_fields' => 1),
        'default_formatter' => 'collapsible',
      ),
      'tabs' => array(
        'label' => t('Vertical tabs group'),
        'description' => t('This fieldgroup renders child groups in its own vertical tabs wrapper.'),
        'instance_settings' => array('classes' => ''),
      ),
      'tab' => array(
        'label' => t('Vertical tab'),
        'description' => t('This fieldgroup renders the content in a fieldset, part of vertical tabs group.'),
        'format_types' => array('open', 'closed'),
        'instance_settings' => array('description' => '', 'classes' => '', 'required_fields' => 1),
        'default_formatter' => 'closed',
      ),
      'multipage-group' => array(
        'label' => ('Multipage group'),
        'description' => t('This fieldgroup renders groups on separate pages.'),
        'instance_settings' => array('classes' => '', 'page_header' => 3, 'move_additional' => 1, 'page_counter' => 1, 'move_button' => 0),
      ),
      'multipage' => array(
        'label' => t('Multipage'),
        'format_types' => array('start', 'no-start'),
        'description' => t('This fieldgroup renders the content in a page.'),
        'default_formatter' => 'no-start',
        'instance_settings' => array('description' => '', 'classes' => '', 'required_fields' => 1),
      ),
      'accordion' => array(
        'label' => t('Accordion group'),
        'description' => t('This fieldgroup renders child groups as jQuery accordion.'),
        'instance_settings' => array('effect' => 'none', 'classes' => ''),
      ),
      'accordion-item' => array(
        'label' => t('Accordion item'),
        'format_types' => array('open', 'closed'),
        'description' => t('This fieldgroup renders the content in a div, part of accordion group.'),
        'default_formatter' => 'closed',
        'instance_settings' => array('description' => '', 'classes' => '', 'required_fields' => 1),
      ),
    ),
    'display' => array(
      'div' => array(
        'label' => t('Div'),
        'description' => t('This fieldgroup renders the inner content in a simple div with the title as legend.'),
        'format_types' => array('open', 'collapsible', 'collapsed'),
        'instance_settings' => array('description' => '', 'show_label' => 1, 'label_element' => 'h3', 'effect' => 'none', 'speed' => 'fast', 'classes' => ''),
        'default_formatter' => 'collapsible',
      ),
      'html5' => array(
        'label' => t('HTML5'),
        'description' => t('This fieldgroup renders the inner content in a semantic HTML5 wrapper'),
        'instance_settings' => array('wrapper' => '', 'classes' => ''),
      ),
      'fieldset' => array(
        'label' => t('Fieldset'),
        'description' => t('This fieldgroup renders the inner content in a fieldset with the title as legend.'),
        'format_types' => array('open', 'collapsible', 'collapsed'),
        'instance_settings' => array('description' => '', 'classes' => ''),
        'default_formatter' => 'collapsible',
      ),
      'tabs' => array(
        'label' => t('Vertical tabs group'),
        'description' => t('This fieldgroup renders child groups in its own vertical tabs wrapper.'),
        'instance_settings' => array('classes' => ''),
      ),
      'tab' => array(
        'label' => t('Vertical tab'),
        'description' => t('This fieldgroup renders the content in a fieldset, part of vertical tabs group.'),
        'format_types' => array('open', 'closed'),
        'instance_settings' => array('description' => '', 'classes' => ''),
        'default_formatter' => 'closed',
      ),
      'accordion' => array(
        'label' => t('Accordion group'),
        'description' => t('This fieldgroup renders child groups as jQuery accordion.'),
        'instance_settings' => array('description' => '', 'classes' => ''),
      ),
      'accordion-item' => array(
        'label' => t('Accordion item'),
        'format_types' => array('open', 'closed'),
        'description' => t('This fieldgroup renders the content in a div, part of accordion group.'),
        'instance_settings' => array('classes' => ''),
        'default_formatter' => 'closed',
      ),
    ),
  );

  // Extra format types derived from elements provided by elements module.
  if (module_exists('elements')) {

    $info['form']['htabs'] = array(
      'label' => ('Horizontal tabs group'),
      'description' => t('This fieldgroup renders child groups in its own horizontal tabs wrapper.'),
      'instance_settings' => array('classes' => ''),
    );
    $info['form']['htab'] = array(
      'label' => t('Horizontal tab item'),
      'format_types' => array('open', 'closed'),
      'description' => t('This fieldgroup renders the content in a fieldset, part of horizontal tabs group.'),
      'default_formatter' => 'closed',
      'instance_settings' => array('description' => '', 'classes' => '', 'required_fields' => 1),
    );
    $info['display']['htabs'] = array(
      'label' => ('Horizontal tabs group'),
      'description' => t('This fieldgroup renders child groups in its own horizontal tabs wrapper.'),
      'instance_settings' => array('classes' => ''),
    );
    $info['display']['htab'] = array(
      'label' => t('Horizontal tab item'),
      'format_types' => array('open', 'closed'),
      'description' => t('This fieldgroup renders the content in a fieldset, part of horizontal tabs group.'),
      'instance_settings' => array('description' => '', 'classes' => ''),
      'default_formatter' => 'closed',
    );

  }

  return $info;
}

/**
 * Implements hook_field_group_format_settings().
 * If the group has no format settings, default ones will be added.
 * @params Object $group The group object.
 * @return Array $form The form element for the format settings.
 */
function field_group_field_group_format_settings($group) {
  // Add a wrapper for extra settings to use by others.
  $form = array(
    'instance_settings' => array(
      '#tree' => TRUE,
      '#weight' => 2,
    ),
  );

  $field_group_types = field_group_formatter_info();
  $mode = $group->mode == 'form' ? 'form' : 'display';
  $formatter = $field_group_types[$mode][$group->format_type];

  // Add the required formatter type selector.
  if (isset($formatter['format_types'])) {
    $form['formatter'] = array(
      '#title' => t('Fieldgroup settings'),
      '#type' => 'select',
      '#options' => drupal_map_assoc($formatter['format_types']),
      '#default_value' => isset($group->format_settings['formatter']) ? $group->format_settings['formatter'] : $formatter['default_formatter'],
      '#weight' => 1,
    );
  }

  if (isset($formatter['instance_settings']['required_fields']) && $mode == 'form') {
    $form['instance_settings']['required_fields'] = array(
      '#type' => 'checkbox',
      '#title' => t('Mark group for required fields.'),
      '#default_value' => isset($group->format_settings['instance_settings']['required_fields']) ? $group->format_settings['instance_settings']['required_fields'] : (isset($formatter['instance_settings']['required_fields']) ? $formatter['instance_settings']['required_fields'] : ''),
      '#weight' => 2,
    );
  }

  if (isset($formatter['instance_settings']['id'])) {
    $form['instance_settings']['id'] = array(
      '#title' => t('ID'),
      '#type' => 'textfield',
      '#default_value' => isset($group->format_settings['instance_settings']['id']) ? $group->format_settings['instance_settings']['id'] : (isset($formatter['instance_settings']['id']) ? $formatter['instance_settings']['id'] : ''),
      '#weight' => 3,
      '#element_validate' => array('field_group_validate_id'),
    );
  }
  if (isset($formatter['instance_settings']['classes'])) {
    $form['instance_settings']['classes'] = array(
      '#title' => t('Extra CSS classes'),
      '#type' => 'textfield',
      '#default_value' => isset($group->format_settings['instance_settings']['classes']) ? $group->format_settings['instance_settings']['classes'] : (isset($formatter['instance_settings']['classes']) ? $formatter['instance_settings']['classes'] : ''),
      '#weight' => 4,
      '#element_validate' => array('field_group_validate_css_class'),
    );
  }

  if (isset($formatter['instance_settings']['description'])) {
    $form['instance_settings']['description'] = array(
      '#title' => t('Description'),
      '#type' => 'textarea',
      '#default_value' => isset($group->format_settings['instance_settings']['description']) ? $group->format_settings['instance_settings']['description'] : (isset($formatter['instance_settings']['description']) ? $formatter['instance_settings']['description'] : ''),
      '#weight' => 0,
    );
  }

  // Add optional instance_settings.
  switch ($group->format_type) {
    case 'div':
      $form['instance_settings']['show_label'] = array(
        '#title' => t('Show label'),
        '#type' => 'select',
        '#options' => array(0 => t('No'), 1 => t('Yes')),
        '#default_value' => isset($group->format_settings['instance_settings']['show_label']) ? $group->format_settings['instance_settings']['show_label'] : $formatter['instance_settings']['show_label'],
        '#weight' => 2,
      );
      $form['instance_settings']['label_element'] = array(
        '#title' => t('Label element'),
        '#type' => 'select',
        '#options' => array('h2' => t('Header 2'), 'h3' => t('Header 3')),
        '#default_value' => isset($group->format_settings['instance_settings']['label_element']) ? $group->format_settings['instance_settings']['label_element'] : $formatter['instance_settings']['label_element'],
        '#weight' => 2,
      );
      $form['instance_settings']['effect'] = array(
        '#title' => t('Effect'),
        '#type' => 'select',
        '#options' => array('none' => t('None'), 'blind' => t('Blind')),
        '#default_value' => isset($group->format_settings['instance_settings']['effect']) ? $group->format_settings['instance_settings']['effect'] : $formatter['instance_settings']['effect'],
        '#weight' => 2,
      );
      $form['instance_settings']['speed'] = array(
        '#title' => t('Speed'),
        '#type' => 'select',
        '#options' => array('none' => t('None'), 'slow' => t('Slow'), 'fast' => t('Fast')),
        '#default_value' => isset($group->format_settings['instance_settings']['speed']) ? $group->format_settings['instance_settings']['speed'] : $formatter['instance_settings']['speed'],
        '#weight' => 3,
      );
      break;
    case 'html5':
      $form['instance_settings']['wrapper'] = array(
        '#title' => t('HTML5 wrapper'),
        '#type' => 'select',
        '#options' => array('section' => t('Section'), 'article' => t('Article'), 'header' => t('Header'), 'footer' => t('footer'), 'aside' => t('Aside')),
        '#default_value' => isset($group->format_settings['instance_settings']['wrapper']) ? $group->format_settings['instance_settings']['wrapper'] : 'section',
      );
      break;
    case 'fieldset':
      break;
    case 'multipage-group':
      $form['instance_settings']['page_header'] = array(
        '#title' => t('Format page title'),
        '#type' => 'select',
        '#options' => array(0 => t('None'), 1 => t('Label only'), 2 => t('Step 1 of 10'), 3 => t('Step 1 of 10 [Label]'),),
        '#default_value' => isset($group->format_settings['instance_settings']['page_header']) ? $group->format_settings['instance_settings']['page_header'] : $formatter['instance_settings']['page_header'],
        '#weight' => 1,
      );
      $form['instance_settings']['page_counter'] = array(
        '#title' => t('Add a page counter at the bottom'),
        '#type' => 'select',
        '#options' => array(0 => t('No'), 1 => t('Format 1 / 10'), 2 => t('The count number only')),
        '#default_value' => isset($group->format_settings['instance_settings']['page_counter']) ? $group->format_settings['instance_settings']['page_counter'] : $formatter['instance_settings']['page_counter'],
        '#weight' => 2,
      );
      $form['instance_settings']['move_button'] = array(
        '#title' => t('Move submit button to last multipage'),
        '#type' => 'select',
        '#options' => array(0 => t('No'), 1 => t('Yes')),
        '#default_value' => isset($group->format_settings['instance_settings']['move_button']) ? $group->format_settings['instance_settings']['move_button'] : $formatter['instance_settings']['move_button'],
        '#weight' => 3,
      );
      $form['instance_settings']['move_additional'] = array(
        '#title' => t('Move additional settings to last multipage (if available)'),
        '#type' => 'select',
        '#options' => array(0 => t('No'), 1 => t('Yes')),
        '#default_value' => isset($group->format_settings['instance_settings']['move_additional']) ? $group->format_settings['instance_settings']['move_additional'] : $formatter['instance_settings']['move_additional'],
        '#weight' => 4,
      );
    case 'tabs':
    case 'htabs':
      break;
    case 'accordion':
      $form['instance_settings']['effect'] = array(
        '#title' => t('Effect'),
        '#type' => 'select',
        '#options' => array('none' => t('None'), 'bounceslide' => t('Bounce slide')),
        '#default_value' => isset($group->format_settings['instance_settings']['effect']) ? $group->format_settings['instance_settings']['effect'] : $formatter['instance_settings']['effect'],
        '#weight' => 2,
      );
      break;
    case 'multipage':
      break;
    case 'tab':
    case 'htab':
    case 'accordion-item':
    default:
  }

  return $form;
}

/**
 * Helper function to prepare basic variables needed for most formatters.
 *
 * Called in field_group_field_group_pre_render(), but can also be called in
 * other implementations of hook_field_group_pre_render().
 */
function field_group_pre_render_prepare(&$group) {

  // Prepare extra classes.
  $group->classes = array('field-group-' . $group->format_type, str_replace('_', '-', $group->group_name));
  if (isset($group->format_settings['formatter'])) {
    $group->collapsible = in_array($group->format_settings['formatter'], array('collapsible', 'collapsed'));
    // Open or closed horizontal or vertical tabs will be collapsible by default.
    if ($group->format_type == 'tab' || $group->format_type == 'htab') {
      $group->collapsible = TRUE;
    }
    $group->collapsed = in_array($group->format_settings['formatter'], array('collapsed', 'closed'));
    if ($group->collapsible) {
      $group->classes[] = 'collapsible';
      if ($group->collapsed) {
        $group->classes[] = 'collapsed';
      }
    }
  }

  // Add a required-fields class to trigger the js.
  if (isset($group->format_settings['instance_settings']) && !empty($group->format_settings['instance_settings']['required_fields'])) {
    $group->classes[] = 'required-fields';
  }

  $group->classes = implode(' ', $group->classes);
  if (isset($group->format_settings['instance_settings'], $group->format_settings['instance_settings']['classes'])) {
    $group->classes .= ' ' . check_plain($group->format_settings['instance_settings']['classes']);
  }

  $group->description = isset($group->format_settings['instance_settings']['description']) ? filter_xss_admin($group->format_settings['instance_settings']['description']) : '';

}

/**
 * Implements hook_field_group_pre_render().
 *
 * @param Array $elements by address.
 * @param Object $group The Field group info.
 */
function field_group_field_group_pre_render(& $element, &$group, & $form) {

  field_group_pre_render_prepare($group);

  $view_mode = isset($form['#view_mode']) ? $form['#view_mode'] : 'form';

  // Add all field_group format types to the js settings.
  $form['#attached']['js'][] = array(
    'data' => array('field_group' => array($group->format_type => $view_mode)),
    'type' => 'setting',
  );
  $form['#attached']['js'][] = 'misc/form.js';
  $form['#attached']['js'][] = 'misc/collapse.js';

  if (isset($group->format_settings['instance_settings']['id']) && !empty($group->format_settings['instance_settings']['id'])) {
    $element['#id'] = $group->format_settings['instance_settings']['id'];
  }
  else {
    $element['#id'] = $form['#entity_type'] . '_' . $form['#bundle'] . '_' . $view_mode . '_' . $group->group_name;
  }

  $element['#weight'] = $group->weight;

  // Call the pre render function for the format type.
  $function = "field_group_pre_render_" . str_replace("-", "_", $group->format_type);
  if (function_exists($function)) {
    $function($element, $group, $form);
  }

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Fieldset.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_fieldset(&$element, $group, &$form) {

  $element += array(
    '#type' => 'fieldset',
    '#title' => check_plain(t($group->label)),
    '#collapsible' => $group->collapsible,
    '#collapsed' => $group->collapsed,
    '#pre_render' => array(),
    '#attributes' => array('class' => explode(' ', $group->classes)),
    '#description' => $group->description,
  );
  $element['#attached']['js'][] = 'misc/form.js';
  $element['#attached']['js'][] = 'misc/collapse.js';

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Div.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_div(&$element, $group, &$form) {

  $show_label = isset($group->format_settings['instance_settings']['show_label']) ? $group->format_settings['instance_settings']['show_label'] : 0;
  $label_element = isset($group->format_settings['instance_settings']['label_element']) ? $group->format_settings['instance_settings']['label_element'] : 'h2';
  $effect = isset($group->format_settings['instance_settings']['effect']) ? $group->format_settings['instance_settings']['effect'] : 'none';
  $speed = isset($group->format_settings['instance_settings']['speed']) ? $group->format_settings['instance_settings']['speed'] : 'none';

  $element['#type'] = 'markup';

  $group->classes .= " speed-$speed effect-$effect";
  if ($group->format_settings['formatter'] != 'open') {
    $element['#prefix'] = '<div id="' . $element['#id'] . '" class="field-group-format ' . $group->classes . '">
      <' . $label_element . '><span class="field-group-format-toggler">' . check_plain(t($group->label)) . '</span></' . $label_element . '>
      <div class="field-group-format-wrapper" style="display: ' . ($group->collapsed ? 'none' : 'block') . ';">';
    $element['#suffix'] = '</div></div>';
  }
  else {
    $element['#prefix'] = '<div id="' . $element['#id'] . '" class="field-group-format ' . $group->group_name . ' ' . $group->classes . '">';
    if ($show_label) {
      $element['#prefix'] .= '<' . $label_element . '><span>' . check_plain(t($group->label)) . '</span></' . $label_element . '>';
    }
    $element['#suffix'] = '</div>';
  }
  if (!empty($group->description)) {
    $element['#prefix'] .= '<div class="description">' . $group->description . '</div>';
  }

  if ($effect == 'blind') {
    drupal_add_library('system', 'effects.blind');
  }

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: HTML5.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_html5(&$element, $group, &$form) {
  $element += array(
    '#type' => 'markup',
    '#prefix' => '<' . $group->format_settings['instance_settings']['wrapper'] . ' id="' . $element['#id'] . '" class="field-group-format ' . $group->classes . '">',
    '#suffix' => '</' . $group->format_settings['instance_settings']['wrapper'] . '>',
  );
}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Accordion.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_accordion(&$element, $group, &$form) {
  $effect = isset($group->format_settings['instance_settings']['effect']) ? $group->format_settings['instance_settings']['effect'] : 'none';

  $group->classes .= " effect-$effect";

  $element += array(
    '#type' => 'markup',
    '#prefix' => '<div class="field-group-' . $group->format_type . '-wrapper ' . $group->classes . '">',
    '#suffix' => '</div>',
  );
}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Accordion item.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_accordion_item(&$element, $group, &$form) {

  $element += array(
    '#type' => 'markup',
    '#prefix' => '<h3 class="field-group-format-toggler ' . $group->format_type . ($group->collapsed ? '' : ' field-group-accordion-active') . '">' . check_plain(t($group->label)) . '</h3>
    <div class="field-group-format-wrapper ' . $group->classes . '">',
    '#suffix' => '</div>',
    //'#attributes' => array('class' => array($group->format_type)),
  );
  if (!empty($group->description)) {
    $element['#prefix'] .= '<div class="description">' . $group->description . '</div>';
  }
  drupal_add_library('system', 'ui.accordion');

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Horizontal tabs group.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_htabs(&$element, $group, &$form) {

  $element += array(
    '#type' => 'horizontal_tabs',
    '#title' => check_plain(t($group->label)),
    '#theme_wrappers' => array('horizontal_tabs'),
    '#prefix' => '<div class="field-group-' . $group->format_type . '-wrapper ' . $group->classes . '">',
    '#suffix' => '</div>',
  );

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Horizontal tab.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_htab(&$element, $group, &$form) {

  $element += array(
    '#type' => 'fieldset',
    '#title' => check_plain(t($group->label)),
    '#collapsible' => $group->collapsible,
    '#collapsed' => $group->collapsed,
    '#attributes' => array('class' => explode(" ", $group->classes)),
    '#group' => $group->parent_name,
    // very important. Cannot be added on the form!
    '#parents' => array($group->parent_name),
    '#description' => $group->description,
  );

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Multipage group.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_multipage_group(&$element, &$group, &$form) {

  $multipage_element = array(
    '#type' => 'multipage',
    '#theme_wrappers' => array('multipage'),
    '#prefix' => '<div class="field-group-' . $group->format_type . '-wrapper ' . $group->classes . '">',
    '#suffix' => '</div>',
  );

  $element += $multipage_element;

  $move_additional = isset($group->format_settings['instance_settings']['move_additional']) ? ($group->format_settings['instance_settings']['move_additional'] && isset($form['additional_settings'])) : isset($form['additional_settings']);
  $move_button = isset($group->format_settings['instance_settings']['move_button']) ? $group->format_settings['instance_settings']['move_button'] : 0;

  drupal_add_js(array(
    'field_group' => array(
      'multipage_move_submit' => (bool) $move_button,
      'multipage_move_additional' => (bool) $move_additional
    )
  ), 'setting');

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Multipage.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_multipage(&$element, $group, &$form) {

  $group->classes .= $group->format_settings['formatter'] == 'start' ? ' multipage-open' : ' multipage-closed';
  $element += array(
    '#type' => 'multipage_pane',
    '#title' => check_plain(t($group->label)),
    '#collapsible' => $group->collapsible,
    '#collapsed' => $group->collapsed,
    '#attributes' => array('class' => explode(" ", $group->classes)),
    '#group' => $group->parent_name,
    '#group_object' => $group,
    '#parent_group_object' => $form['#groups'][$group->parent_name],
    // very important. Cannot be added on the form!
    '#parents' => array($group->parent_name),
    '#description' => $group->description,
  );

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Vertical tabs wrapper.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_tabs(&$element, $group, &$form) {

  $element += array(
    '#type' => 'vertical_tabs',
    '#theme_wrappers' => array('vertical_tabs'),
    '#prefix' => '<div class="field-group-' . $group->format_type . '-wrapper ' . $group->classes . '">',
    '#suffix' => '</div>',
  );
  $element[$group->group_name . '__active_tab'] = array(
    '#type' => 'hidden',
    '#default_value' => '',
    '#attributes' => array('class' => array('vertical-tabs-active-tab')),
  );
  $form['#attached']['library'][] = array('system', 'drupal.form');
  $form['#attached']['library'][] = array('system', 'drupal.collapse');

}

/**
 * Implements field_group_pre_render_<format-type>.
 * Format type: Vertical tab.
 *
 * @param $element The field group form element.
 * @param $group The Field group object prepared for pre_render.
 * @param $form The root element or form.
 */
function field_group_pre_render_tab(&$element, $group, &$form) {

  $view_mode = isset($form['#view_mode']) ? $form['#view_mode'] : 'form';

  // Could be it never runs through htab.
  $form['#attached']['js'][] = array(
    'data' => array('field_group' => array('tabs' => $view_mode)),
    'type' => 'setting',
  );

  $add = array(
    '#type' => 'fieldset',
    '#id' => 'edit-' . $group->group_name,
    '#title' => check_plain(t($group->label)),
    '#collapsible' => $group->collapsible,
    '#collapsed' => $group->collapsed,
    '#attributes' => array('class' => explode(" ", $group->classes)),
    '#description' => $group->description,
  );

  // Front-end and back-end on configuration will lead
  // to vertical tabs nested in a separate vertical group.
  if ($view_mode != 'form') {
    $add['#group'] = empty($group->parent_name) ? 'additional_settings' : $group->parent_name;
    $add['#parents'] = array($add['#group']);
    $element += $add;
  }
  // Form fieldgroups which are nested into a vertical tab group
  // are handled a little different.
  elseif (!empty($group->parent_name)) {
    $add['#group'] = $group->parent_name;
    $element += $add;
  }
  // Forms "can" have additional settins. We'll try to locate it first, if not
  // exists, field_group will create a parallel additional settings entry.
  else {
    // Create the fieldgroup element.
    $add['#parents'] = array('additional_settings');
    $add['#group'] = 'additional_settings';
    $add['#weight'] = -30 + $group->weight; // hardcoded to bring our extra additional vtabs on top.

    // Check if the additional_settings exist for this type of form.
    if (isset($form['additional_settings']['group']['#groups']['additional_settings'])) {

      // Merge fieldgroups with the core additional settings.
      $form['additional_settings']['group']['#groups']['additional_settings'][$group->group_name] = $add;
      $form['additional_settings']['group']['#groups'][$group->group_name] = array('#group_exists' => TRUE);
      // Nest the fields inside the appropriate structure.
      foreach (element_children($element) as $fieldname) {
        $form['additional_settings']['group']['#groups']['additional_settings'][$group->group_name][$fieldname] = &$element[$fieldname];
        unset($element[$fieldname]);
      }
    }
    // Assumption the wrapper is in the root. This could be done by field_group itself
    // in previous loop of tabs in same wrapper or even some other contrib / custom module.
    else {
      if (!isset($form['additional_settings']['#type'])) {
        $form['additional_settings'] = array(
          '#type' => 'vertical_tabs',
          '#weight' => $group->weight,
          '#theme_wrappers' => array('vertical_tabs'),
          '#prefix' => '<div class="field-group-' . $group->format_type . '-wrapper">',
          '#suffix' => '</div>',
        );
        $form['#attached']['js'][] = 'misc/form.js';
        $form['#attached']['js'][] = 'misc/collapse.js';
      }
      $form['additional_settings'][$group->group_name] = $add;
      // Nest the fields inside the appropriate structure.
      foreach (element_children($element) as $fieldname) {
        $form['additional_settings'][$group->group_name][$fieldname] = &$element[$fieldname];
        unset($element[$fieldname]);
      }
    }
  }

}

/**
 * Implements hook_field_group_build_pre_render_alter().
 * @param Array $elements by address.
 */
function field_group_field_group_build_pre_render_alter(& $element) {

  // Someone is doing a node view, in a node view. Reset content.
  // TODO Check if this breaks something else.
  if (isset($element['#node']->content) && count($element['#node']->content) > 0) {
    $element['#node']->content = array();
  }

  $display = isset($element['#view_mode']);
  $groups = array_keys($element['#groups']);

  // Dish the fieldgroups with no fields for non-forms.
  if ($display) {
    field_group_remove_empty_display_groups($element, $groups);
  }
  else {
    // Fix the problem on forms with additional settings.
    field_group_remove_empty_form_groups('form', $element, $groups, $element['#groups'], $element['#entity_type']);
  }

  // Add the default field_group javascript and stylesheet.
  $element['#attached']['js'][] = drupal_get_path('module', 'field_group') . '/field_group.js';
  $element['#attached']['css'][] = drupal_get_path('module', 'field_group') . '/field_group.css';

  // Move additional settings to the last multipage pane if configured that way.
  // Note that multipages MUST be in the root of the form.
  foreach (element_children($element) as $name) {
    if (isset($element[$name]['#type']) && $element[$name]['#type'] == 'multipage' && isset($element['additional_settings'])) {
      $parent_group = $element['#groups'][$name];
      $move_additional = isset($parent_group->format_settings['instance_settings']['move_additional']) ? $parent_group->format_settings['instance_settings']['move_additional'] : 1;
      $last_pane = NULL;
      foreach (element_children($element[$name], TRUE) as $pane) {
        $last_pane = $pane;
      }
      $element[$name][$last_pane]['additional_settings'] = $element['additional_settings'];
      unset($element['additional_settings']);
    }
  }

}

/**
 * Remove empty groups on forms.
 *
 * @param String $parent_name
 *   The name of the element.
 * @param array $element
 *   The element to check the empty state.
 * @param array $groups
 *   Array of group objects.
 */
function field_group_remove_empty_form_groups($name, & $element, $groups, &$form_groups, $entity) {

  $exceptions = array('user__account', 'comment__author');

  $children = element_children($element);

  $hasChildren = FALSE;
  if (count($children)) {
    foreach ($children as $childname) {
      if (in_array($childname, $groups)) {
        field_group_remove_empty_form_groups($childname, $element[$childname], $groups, $form_groups, $entity);
      }
      $exception = $entity . '__' . $childname;
      $hasChildren = $hasChildren ? TRUE : (isset($element[$childname]['#type']) || in_array($exception, $exceptions));
    }
  }

  if (!$hasChildren) {

    // Remove empty elements from the #groups.
    if (empty($element) && isset($form_groups[$name]) && !is_array($form_groups[$name])) {
      foreach ($form_groups as $group_name => $group) {
        if (isset($group->children)) {
          $group_children = array_flip($group->children);
          if (isset($group_children[$name])) {
            unset($form_groups[$group_name]->children[$group_children[$name]]);
          }
        }
      }
    }

    $element['#access'] = FALSE;

  }

}

/**
 * Remove empty groups on entity display.
 * @param array $element
 *   The element to check the empty state.
 * @param array $groups
 *   Array of group objects.
 */
function field_group_remove_empty_display_groups(& $element, $groups) {

  $empty_child = TRUE;
  $empty_group = TRUE;

  // Loop through the children for current element.
  foreach (element_children($element) as $name) {

    // Descend if the child is a group.
    if (in_array($name, $groups)) {
      $empty_child = field_group_remove_empty_display_groups($element[$name], $groups);
      if (!$empty_child) {
        $empty_group = FALSE;
      }
    }
    // Child is a field, the element is not empty.
    elseif (!empty($element[$name])) {
      $empty_group = FALSE;
    }

  }

  // Reset an empty group.
  if ($empty_group) {
    $element = NULL;
  }

  return $empty_group;

}

/**
 * Implements hook_field_group_format_summary().
 */
function field_group_field_group_format_summary($group) {

  $group_form = module_invoke_all('field_group_format_settings', $group);

  $output = '';
  if (isset($group->format_settings['formatter'])) {
    $output .= '<strong>' . $group->format_type . '</strong> ' . $group->format_settings['formatter'] . '';
  }
  if (isset($group->format_settings['instance_settings'])) {
    $last = end($group->format_settings['instance_settings']);
    $output .= '<br />';
    foreach ($group->format_settings['instance_settings'] as $key => $value) {
      if (empty($value)) {
        continue;
      }

      $output .= '<strong>' . $key . '</strong> ';

      if (isset($group_form['instance_settings'], $group_form['instance_settings'][$key]['#options'])) {
        $value = $group_form['instance_settings'][$key]['#options'][$value];
      }

      // Shorten the string.
      if (drupal_strlen($value) > 38) {
        $value = truncate_utf8($value, 50, TRUE, TRUE);
      }
      // If still numeric, handle it as yes or no.
      elseif (is_numeric($value)) {
        $value = $value == '1' ? t('yes') : t('no');
      }
      $output .= check_plain($value);
      $output .= $last == $value ? ' ' : '<br />';
    }
  }
  return $output;
}

/**
 * Implements hook_element_info().
 */
function field_group_element_info() {
  $types = array();
  $types['multipage'] = array(
    '#theme_wrappers' => array('multipage'),
    '#default_tab' => '',
    '#process' => array('form_process_multipage'),
  );
  $types['multipage_pane'] = array(
    '#value' => NULL,
    '#process' => array('form_process_fieldset', 'ajax_process_form'),
    '#pre_render' => array('form_pre_render_fieldset'),
    '#theme_wrappers' => array('multipage_pane'),
  );
  return $types;
}

/**
 * Implements hook_library().
 */
function field_group_library() {

  $path = drupal_get_path('module', 'field_group');

  // Multipage Tabs.
  $libraries['multipage'] = array(
    'title' => 'Multipage',
    'website' => 'http://drupal.org/node/323112',
    'version' => '1.0',
    'js' => array(
      $path . '/multipage/multipage.js' => array(),
    ),
    'css' => array(
      $path . '/multipage/multipage.css' => array(),
    ),
  );

  return $libraries;
}

/**
 * Implements hook_field_attach_rename_bundle().
 * TODO: also update identifier
 */
function field_group_field_attach_rename_bundle($entity_type, $bundle_old, $bundle_new) {
  db_query('UPDATE {field_group} SET bundle = :bundle WHERE bundle = :old_bundle AND entity_type = :entity_type', array(
    ':bundle' => $bundle_new,
    ':old_bundle' => $bundle_old,
    ':entity_type' => $entity_type,
  ));
}

/**
 * Creates a group formatted as multipage.
 * This function will never be callable from within field_group rendering. Other
 * modules using #type multipage will have the benefit of this processor.
 *
 * @param $element
 *   An associative array containing the properties and children of the
 *   fieldset.
 * @param $form_state
 *   The $form_state array for the form this multipage tab widget belongs to.
 * @return
 *   The processed element.
 */
function form_process_multipage($element, &$form_state) {
  // Inject a new fieldset as child, so that form_process_fieldset() processes
  // this fieldset like any other fieldset.
  $element['group'] = array(
    '#type' => 'fieldset',
    '#theme_wrappers' => array(),
    '#parents' => $element['#parents'],
  );

  // The JavaScript stores the currently selected tab in this hidden
  // field so that the active control can be restored the next time the
  // form is rendered, e.g. on preview pages or when form validation
  // fails.
  $name = implode('__', $element['#parents']);
  if (isset($form_state['values'][$name . '__active_control'])) {
    $element['#default_tab'] = $form_state['values'][$name . '__active_control'];
  }
  $element[$name . '__active_control'] = array(
    '#type' => 'hidden',
    '#default_value' => $element['#default_control'],
    '#attributes' => array('class' => array('multipage-active-control')),
  );

  return $element;
}

/**
 * Returns HTML for an element's children fieldsets as multipage.
 *
 * @param $variables
 *   An associative array containing:
 *   - element: An associative array containing the properties and children of the
 *     fieldset. Properties used: #children.
 *
 * @ingroup themeable
 */
function theme_multipage($variables) {
  $element = $variables['element'];
  // Add required JavaScript and Stylesheet.
  drupal_add_library('field_group', 'multipage');

  $output = '<h2 class="element-invisible">' . (!empty($element['#title']) ? $element['#title'] : t('Multipage')) . '</h2>';

  $output .= '<div class="multipage-panes">';
  $output .= $element['#children'];
  $output .= '</div>';

  return $output;
}

/**
 * Returns HTML for multipage pane.
 *
 * @param $variables
 *   An associative array containing:
 *   - element: An associative array containing the properties and children of the
 *     fieldset. Properties used: #children.
 *
 * @ingroup themeable
 */
function theme_multipage_pane($variables) {

  $element = $variables['element'];
  $group = $variables['element']['#group_object'];
  $parent_group = $variables['element']['#parent_group_object'];

  static $multipages;
  if (!isset($multipages[$group->parent_name])) {
    $multipages = array($group->parent_name => 0);
  }
  $multipages[$parent_group->group_name]++;

  // Create a page title from the label.
  $page_header = isset($parent_group->format_settings['instance_settings']['page_header']) ? $parent_group->format_settings['instance_settings']['page_header'] : 3;
  switch ($page_header) {
    case 1:
      $title = $element['#title'];
      break;
    case 2:
      $title = t('Step %count of %total', array('%count' => $multipages[$parent_group->group_name], '%total' => count($parent_group->children)));
      break;
    case 3:
      $title = t('Step %count of %total !label', array('%count' => $multipages[$parent_group->group_name], '%total' => count($parent_group->children), '!label' => $element['#title']));
      break;
    case 0:
    default:
      $title = '';
      break;
  }

  element_set_attributes($element, array('id'));
  _form_set_class($element, array('form-wrapper'));

  $output = '<div' . drupal_attributes($element['#attributes']) . '>';
  if (!empty($element['#title'])) {
    // Always wrap fieldset legends in a SPAN for CSS positioning.
    $output .= '<h2 class="multipage-pane-title"><span>' . $title . '</span></h2>';
  }
  $output .= '<div class="fieldset-wrapper multipage-pane-wrapper">';
  if (!empty($element['#description'])) {
    $output .= '<div class="fieldset-description">' . $element['#description'] . '</div>';
  }
  $output .= $element['#children'];
  if (isset($element['#value'])) {
    $output .= $element['#value'];
  }

  // Add a page counter if needed.
  // counter array(0 => t('No'), 1 => t('Format 1 / 10'), 2 => t('The count number only'));
  $page_counter_format = isset($parent_group->format_settings['instance_settings']['page_counter']) ? $parent_group->format_settings['instance_settings']['page_counter'] : 1;
  $multipage_element['#page_counter_rendered'] = '';
  if ($page_counter_format == 1) {
    $output .= t('<span class="multipage-counter">%count / %total</span>', array('%count' => $multipages[$parent_group->group_name], '%total' => count($parent_group->children)));
  }
  elseif ($page_counter_format == 2) {
    $output .=  t('<span class="multipage-counter">%count</span>', array('%count' => $multipages[$parent_group->group_name]));
  }

  $output .= '</div>';
  $output .= "</div>\n";

  return $output;

}

/**
 * Get all groups.
 *
 * @param $entity_type
 *   The name of the entity.
 * @param $bundle
 *   The name of the bundle.
 * @param $view_mode
 *   The view mode.
 * @param $reset.
 *   Whether to reset the cache or not.
 */
function field_group_info_groups($entity_type = NULL, $bundle = NULL, $view_mode = NULL, $reset = FALSE) {
  static $groups = FALSE;

  if (!$groups || $reset) {
    if (!$reset && $cached = cache_get('field_groups', 'cache_field')) {
      $groups = $cached->data;
    }
    else {
      drupal_static_reset('ctools_export_load_object');
      drupal_static_reset('ctools_export_load_object_all');
      $groups = field_group_read_groups();
      cache_set('field_groups', $groups, 'cache_field');
    }
  }

  if (!isset($entity_type)) {
    return $groups;
  }
  else {
    if (isset($groups[$entity_type][$bundle][$view_mode])) {
      return $groups[$entity_type][$bundle][$view_mode];
    }
    else {
      return array();
    }
  }
}

/**
 * Read all groups.
 *
 * @param $params
 *   Parameters for the query
 *   $name The name of the entity.
 *   $bundle The name of the bundle.
 *   $view_mode The view mode.
 */
function field_group_read_groups($params = array()) {

  $groups = array();
  ctools_include('export');

  if (empty($params)) {
    $records = ctools_export_load_object('field_group');
  }
  else {
    $records = ctools_export_load_object('field_group', 'conditions', $params);
  }

  foreach ($records as $group) {
    // Deleted groups.
    // @TODO remove the code below and add something meaningfull for "disabled" state.
    if (isset($group->disabled) && $group->disabled) {
      continue;
    }
    $groups[$group->entity_type][$group->bundle][$group->mode][$group->group_name] = field_group_unpack($group);
  }
  return $groups;

}

/**
 * Utility function to recreate identifiers.
 */
function _field_group_recreate_identifiers() {

  // Migrate the field groups so they have a unique identifier.
  $result = db_select('field_group', 'fg')
    ->fields('fg')
    ->execute();
  $rows = array();
  foreach($result as $row) {
    $row->identifier = $row->group_name . '|' . $row->entity_type . '|' . $row->bundle . '|' . $row->mode;
    $row->data = unserialize($row->data);
    $rows[] = $row;
  }
  foreach ($rows as $row) {
    drupal_write_record('field_group', $row, array('id'));
  }

}

/**
 * Checks if a field_group exists in required context.
 *
 * @param String $group_name
 *   The name of the group.
 * @param String $entity_type
 *   The name of the entity.
 * @param String $bundle
 *   The bundle for the entity.
 * @param String $mode
 *   The view mode context the group will be rendered.
 */
function field_group_exists($group_name, $entity_type, $bundle, $mode) {
  $groups = field_group_read_groups();
  return !empty($groups[$entity_type][$bundle][$mode][$group_name]);
}

/**
 * Unpacks a database row in a FieldGroup object.
 * @param $group
 *   Database result object with stored group data.
 * @return $group
 *   Field group object.
 */
function field_group_unpack($group) {

  // Extract unserialized data.
  if (isset($group->data)) {
    $data = $group->data;
    unset($group->data);
    $group->label = $data['label'];
    $group->weight = $data['weight'];
    $group->children = $data['children'];
    $group->format_type = !empty($data['format_type']) ? $data['format_type'] : 'fieldset';
    if (isset($data['format_settings'])) {
      $group->format_settings = $data['format_settings'];
    }
  }

  return $group;

}

/**
 * Packs a FieldGroup object into a database row.
 * @param $group
 *   FieldGroup object.
 * @return $record
 *   Database row object, ready to be inserted/update
 */
function field_group_pack($group) {

  $record = clone $group;
  $record->data = array(
    'label' => $record->label,
    'weight' => $record->weight,
    'children' => $record->children,
    'format_type' => !empty($record->format_type) ? $record->format_type : 'fieldset',
  );
  if (isset($record->format_settings)) {
    $record->data['format_settings'] = $record->format_settings;
  }
  return $record;
}

/**
 * Delete a field group.
 * This function is also called by ctools export when calls are
 * made through ctools_export_crud_delete().
 *
 * @param $group
 *   A group definition.
 * @param $ctools_crud
 *  Is this function called by the ctools crud delete.
 */
function field_group_group_export_delete($group, $ctools_crud = TRUE) {

  $query = db_delete('field_group');

  if (isset($group->identifier)) {
    $query->condition('identifier', $group->identifier);
    if (!$ctools_crud) {
      ctools_export_crud_disable('field_group', $group->identifier);
    }
  }
  elseif (isset($group->id)) {
    $query->condition('id', $group->id);
  }

  if (!empty($group->mode)) {
    $query->condition('mode', $group->mode);
  }

  $query->execute();

  cache_clear_all('field_groups', 'cache_field');
  module_invoke_all('field_group_delete_field_group', $group);

}

/**
 * field_group_group_save().
 *
 * Saves a group definition.
 * This function is called by ctools export when calls are made
 * through ctools_export_crud_save().
 *
 * @param $group
 *   A group definition.
 */
function field_group_group_save(& $group) {

  // Prepare the record.
  $object = field_group_pack($group);

  if (isset($object->export_type) && $object->export_type & EXPORT_IN_DATABASE) {
    // Existing record.
    $update = array('id');
    module_invoke_all('field_group_update_field_group', $object);
  }
  else {
    // New record.
    $update = array();
    $object->export_type = EXPORT_IN_DATABASE;
    module_invoke_all('field_group_create_field_group', $object);
  }
  return drupal_write_record('field_group', $object, $update);

}

/**
 * Function to retrieve all format possibilities for the fieldgroups.
 */
function field_group_formatter_info($display_overview = FALSE) {
  $cache = &drupal_static(__FUNCTION__, array());
  if (empty($cache)) {
    if ($cached = cache_get('field_group_formatter_info', 'cache_field')) {
      $formatters = $cached->data;
    }
    else {
      $formatters = array();
      $formatters += module_invoke_all('field_group_formatter_info');
      $hidden_region = array(
        'label' => t('<Hidden>'),
        'description' => '',
        'format_types' => array(),
        'instance_settings' => array(),
        'default_formatter' => '',
      );
      //$formatters['form']['hidden'] = $hidden_region;
      $formatters['display']['hidden'] = $hidden_region;
      cache_set('field_group_formatter_info', $formatters, 'cache_field');
    }
    $cache = $formatters;
  }
  return $cache;
}

/**
 * Attach groups to the (form) build.
 *
 * @param Array $element
 *   The part of the form.
 * @param String $view_mode
 *   The mode for the build.
 * @param Array $form_state
 *   The optional form state when in view_mode = form context.
 */
function field_group_attach_groups(&$element, $view_mode, $form_state = array()) {

  $entity_type = $element['#entity_type'];
  $bundle = $element['#bundle'];

  $element['#groups'] = field_group_info_groups($entity_type, $bundle, $view_mode);
  $element['#fieldgroups'] = $element['#groups'];

  // Create a lookup array.
  $group_children = array();
  foreach ($element['#groups'] as $group_name => $group) {
    foreach ($group->children as $child) {
      $group_children[$child] = $group_name;
    }
  }
  $element['#group_children'] = $group_children;

}

/**
 * Pre render callback for rendering groups.
 * @see field_group_field_attach_form
 * @param $element Form that is beïng rendered.
 */
function field_group_form_pre_render(&$element) {
  return field_group_build_entity_groups($element, 'form');
}

/**
 * Preprocess/ Pre-render callback.
 *
 * @see field_group_form_pre_render()
 * @see field_group_theme_registry_alter
 * @see field_group_fields_nest()
 * @param $vars preprocess vars or form element
 * @param $type The type of object beïng rendered
 * @return $element Array with re-arranged fields in forms.
 */
function field_group_build_entity_groups(&$vars, $type) {

  if ($type == 'form') {
    $element = &$vars;
    $nest_vars = NULL;
  }
  else {
    $element = &$vars['elements'];
    $nest_vars = &$vars;
  }

  // No groups on the entity.
  if (empty($element['#groups'])) {
    return $element;
  }

  // Nest the fields in the corresponding field groups.
  field_group_fields_nest($element, $nest_vars);

  // Allow others to alter the pre_rendered build.
  drupal_alter('field_group_build_pre_render', $element);

  // Return the element on forms.
  if ($type == 'form') {
    return $element;
  }

  // Put groups inside content if we are rendering an entity_view.
  foreach ($element['#groups'] as $group) {
    if (!empty($element[$group->group_name])) {
      $vars['content'][$group->group_name] = $element[$group->group_name];
    }
  }
}

/**
 * Recursive function to nest fields in the field groups.
 *
 * This function will take out all the elements in the form and
 * place them in the correct container element, a fieldgroup.
 * The current group element in the loop is passed recursively so we can
 * stash fields and groups in it while we go deeper in the array.
 * @param Array $element
 *   The current element to analyse for grouping.
 * @param Array $vars
 *   Rendering vars from the entity beïng viewed.
 */
function field_group_fields_nest(&$element, &$vars = NULL) {

  // Create all groups and keep a flat list of references to these groups.
  $group_references = array();
  foreach ($element['#groups'] as $group_name => $group) {
    $element[$group_name] = array();
    $group_references[$group_name] = &$element[$group_name];
  }

  // Move all children to their parents. Use the flat list of references for
  // direct access as we don't know where in the root_element hierarchy the
  // parent currently is situated.
  foreach ($element['#group_children'] as $child_name => $parent_name) {

    // Entity beïng viewed
    if ($vars) {
      // If not a group, check vars['content'] for empty field.
      if (!isset($element['#groups'][$child_name]) && isset($vars['content'][$child_name])) {
        $group_references[$parent_name][$child_name] = $vars['content'][$child_name];
        unset($vars['content'][$child_name]);
      }
      // If this is a group, we have to use a reference to keep the reference
      // list intact (but if it is a field we don't mind).
      else {
        $group_references[$parent_name][$child_name] = &$element[$child_name];
        unset($element[$child_name]);
      }
    }
    // Form beïng viewed
    else {

      // Block denied fields (#access) before they are put in groups.
      // Fields (not groups) that don't have children (like field_permissions) are removed
      // in field_group_field_group_build_pre_render_alter.
      if (isset($element[$child_name]) && (!isset($element[$child_name]['#access']) || $element[$child_name]['#access'])) {
        // If this is a group, we have to use a reference to keep the reference
        // list intact (but if it is a field we don't mind).
        $group_references[$parent_name][$child_name] = &$element[$child_name];
      }

      // The child has been copied to its parent: remove it from the root element.
      unset($element[$child_name]);
    }

  }

  // Bring extra element wrappers to achieve a grouping of fields.
  // This will mainly be prefix and suffix altering.
  foreach ($element['#groups'] as $group_name => $group) {
    field_group_pre_render($group_references[$group_name], $group, $element);
  }

}

/**
 * Function to pre render the field group element.
 *
 * @see field_group_fields_nest()
 *
 * @param $element Array of group element that needs to be created!
 * @param $group Object with the group information.
 * @param $form The form object itself.
 */
function field_group_pre_render(& $element, $group, & $form) {

  // Only run the pre_render function if the group has elements.
  // $group->group_name
  if ($element == array()) {
    return;
  }

  // Let modules define their wrapping element.
  // Note that the group element has no properties, only elements.
  foreach (module_implements('field_group_pre_render') as $module) {
    $function = $module . '_field_group_pre_render';
    if (function_exists($function)) {
      // The intention here is to have the opportunity to alter the
      // elements, as defined in hook_field_group_formatter_info.
      // Note, implement $element by reference!
      $function($element, $group, $form);
    }
  }

  // Allow others to alter the pre_render.
  drupal_alter('field_group_pre_render', $element, $group, $form);

}