ding_nodelist.module

<?php

/**
 * @file
 * Helps creating customizable lists of content
 * that can be placed on a panel.
 */
define('NL_WIDGET_LIST', 'simple');
define('NL_WIDGET_SINGLE', 'single');
define('NL_WIDGET_CAROUSEL', 'carousel');
define('NL_WIDGET_HOR_ACCORDION', 'horizontal_accordion');
define('NL_WIDGET_VER_ACCORDION', 'vertical_accordion');
define('NL_WIDGET_SLIDER', 'slider');
define('NL_WIDGET_TAXONOMY_LIKE', 'taxonomy');

define('NL_COL_FULL', 'full');
define('NL_COL_HALF', 'half');
define('NL_COL_THIRD', 'third');
define('NL_COL_QRT', 'quarter');

define('NL_TPL_ACTIVE', 0);
define('NL_TPL_HIDDEN', 1);

define('NL_CACHE_LIFETIME', 1800);

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

  $items['admin/config/ding/ding_nodelist'] = array(
    'title' => 'Ding nodelist',
    'description' => 'View and customize lists of content.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ding_nodelist_settings_form'),
    'access arguments' => array('configure nodelist'),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'ding_nodelist.admin.inc',
  );

  $items['admin/config/ding/ding_nodelist/settings'] = array(
    'title' => 'Settings',
    'description' => 'Configure general settings.',
    'tab_parent' => 'admin/config/ding/ding_nodelist',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'file' => 'ding_nodelist.admin.inc',
  );

  $items['admin/config/ding/ding_nodelist/templates'] = array(
    'title' => 'Templates',
    'description' => 'Manage content templates.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('ding_nodelist_templates_form'),
    'access arguments' => array('configure nodelist'),
    'type' => MENU_LOCAL_TASK,
    'file' => 'ding_nodelist.admin.inc',
  );

  $items['ding_nodelist/autocomplete/%'] = array(
    'page callback' => 'ding_nodelist_autocomplete',
    'page arguments' => array(2),
    // @todo: implements permissions for nodelist managements
    //'access arguments' => array('create nodelist instances'),
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
 * Implements hook_permission().
 */
function ding_nodelist_permission() {
  return array(
    'configure nodelist' => array(
      'title' => t('Configure nodelist'),
      'description' => t('Configure the behavior of nodelist'),
    ),
    'nodelist cache settings' => array(
      'title' => t('Nodelist cache'),
      'description' => t('Manage nodelist cache settings'),
    ),
    // @todo: this permission is declared but not implemented.
    // IPE is known to have additional non-documented features regarding permissions.
    // 'create nodelist instances' => array(
    //       'title' => t('Manage nodelist instances'),
    //       'description' => t('Create/edit/delete nodelist instances'),
    //  ),
  );
}

/**
 * Implements hook_ctools_plugin_directory().
 * This lets ctools know to scan the module for a content_type plugin file.
 */
function ding_nodelist_ctools_plugin_directory($module, $plugin) {
  // we'll be nice and limit scandir() calls
  if ($module == 'ctools' && $plugin == 'content_types') {
    return 'plugins/content_types';
  }
}

/**
 * Implements hook_ajax_render_alter().
 * This method is a workaround to impossiblity
 * of telling Drupal the order of CSS files in order to
 * cascade styles properly. See the link.
 *
 * @link http://drupal.org/node/561858#comment-3171846
 * @global boolean $ipe_mode
 * @param array $commands
 *   Ajax render commands.
 */
function ding_nodelist_ajax_render_alter(&$commands) {
  global $ipe_mode, $ipe_redirect;
  if ($ipe_mode) {
    $path = drupal_get_path('module', 'ding_nodelist') . "/css/ipe.css";
    $styles = '<style type="text/css" media="all">@import url("' . $path . '");</style>';
    $commands[] = ajax_command_append('head', $styles);
  }

  if ($ipe_redirect) {
    ctools_include('ajax');
    ctools_add_js('ajax-responder');
    $commands[] = ctools_ajax_command_redirect($ipe_redirect);
  }
}

/**
 * Implements hook_BASE_FORM_ID_alter().
 * Add custom handler to IPE Save/Cancel buttons to force page reload.
 */
function ding_nodelist_form_panels_ipe_edit_control_form_alter(&$form, &$form_state) {
  $form['buttons']['submit']['#submit'][] = '_ding_nodelist_ipe_buttons_submit';
  $form['buttons']['cancel']['#submit'][] = '_ding_nodelist_ipe_buttons_submit';
  // Add necessary scripts for later call in ding_nodelist_ajax_render_alter().
  ctools_include('ajax');
  ctools_add_js('ajax-responder');
}

/**
 * Save/Cancel IPE buttons submit handler.
 */
function _ding_nodelist_ipe_buttons_submit($form, &$form_state) {
  global $ipe_redirect;
  $ipe_redirect = $_SERVER['HTTP_REFERER'];
}

/**
 * Ctools plugin callback for settings form.
 */
function ding_nodelist_content_type_edit_form($form, &$form_state) {
  drupal_add_css(drupal_get_path('module', 'ding_nodelist') . '/css/ding_nodelist-admin.css', 'file');
  global $ipe_mode;

  // Tell to load additional CSS to make edit form look normally
  // in case of IPE.
  if (strpos($form_state['form_info']['path'], '/ipe/')) {
    $ipe_mode = TRUE;
  }

  // Cache the form for correct workflow.
  $form_state['cache'] = TRUE;

  // Save original form to restore it later.
  // @todo: remove this workaround code and find ctools/drupal-way approach.
  if (!isset($form_state['restore'])) {
    $form_state['original_form'] = $form;
  }

  $trigger = !empty($form_state['triggering_element']) ? $form_state['triggering_element'] : NULL;

  // CT/widget select change handlers.
  // Process them first since they affect the rest of the form.
  if ($trigger) {
    if ($trigger['#name'] == 'content_type') {
      // Refresh CT setting.
      $node_type = $form_state['triggering_element']['#value'];

      // Reset other form values.
      $form_state['values']['content_type'] = $node_type;
      $form_state['values']['selected_nodes'] = array();
      $form_state['values']['widget_type'] = '';
      $form_state['values']['taxonomy_filters'] = array();
      unset($form_state['input']);
      _ding_nodelist_content_type_form_save($form_state, TRUE);
    }
    elseif ($trigger['#name'] == 'widget_type') {
      $node_type = $form_state['values']['content_type'];
      // Reset default scrolling delay.
      unset($form_state['input']['autoscroll_delay']);
      $form_state['values']['autoscroll_delay'] = '';
      _ding_nodelist_content_type_form_save($form_state, TRUE);
    }
  }

  $conf = $form_state['conf'];

  // Show only allowed content types.
  $node_types = variable_get('ding_nodelist_node_types', array());
  $all_node_types = node_type_get_names();
  $node_types_opts = array();
  foreach ($node_types as $nt => $active) {
    if ($active) {
      $node_types_opts[$nt] = $all_node_types[$nt];
    }
  }

  if (empty($node_types_opts)) {
    drupal_set_message(t('No eligible content types were found, please configure a few first.'), 'error', FALSE);
  }

  $node_type = isset($conf['content_type']) ? $conf['content_type'] : current(array_keys($node_types));

  $default_conf = array(
    'content_type' => $node_type,
    'widget_type' => NL_WIDGET_CAROUSEL,
    'columns' => NL_COL_FULL,
    'sort_field' => 'created',
    'limit' => 5,
    'more_text' => t('More'),
    'more_link' => '',
    'teaser_length' => 100,
    'autoscroll_delay' => 3000,
  );

  $form['#prefix'] = '<div id="ding_nodelist-form-wrapper">';
  $form['#suffix'] = '</div>';

  // Initial settings.
  $form['ding_nodelist_wrapper'] = array(
    '#type' => 'fieldset',
    '#collapsible' => FALSE,
    '#tree' => FALSE,
    '#title' => t('Configure nodelist'),
    '#collapsible' => FALSE,
  );

  $form['ding_nodelist_wrapper']['content_type'] = array(
    '#type' => 'select',
    '#title' => t('Content type'),
    '#required' => TRUE,
    '#default_value' => $node_type,
    '#options' => $node_types_opts,
    '#description' => t('Select the content type of the list\'s items.'),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-selected-nodes',
      'callback' => 'ding_nodelist_js',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );

  // Set up all the available view modes for this type of nodes.
  $entity = entity_get_info('node');
  $node_formats = array();
  foreach ($entity['view modes'] as $view_mode => $settings) {
    $node_formats[$view_mode] = $settings['label'];
  }

  $widget_types = _ding_nodelist_get_widget_types($node_type);
  $widget_type = isset($conf['widget_type']) ? $conf['widget_type'] : $default_conf['widget_type'];
  $form['ding_nodelist_wrapper']['widget_type'] = array(
    '#type' => 'select',
    '#title' => t('List type'),
    '#required' => TRUE,
    '#default_value' => $widget_type,
    '#options' => $widget_types,
    '#empty_option' => t('- Select -'),
    '#description' => t('If single item selected, only the first item will be rendered'),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-item-template',
      'callback' => 'ding_nodelist_js_template',
      'method' => 'replace',
      'effect' => 'fade',
    ),
    '#prefix' => '<div class=ding_nodelist-widget-config>',
  );

  $form['ding_nodelist_wrapper']['widget_dependent'] = array(
    '#type' => 'container',
    '#prefix' => '<div id="ding_nodelist-item-template">',
    '#suffix' => '</div></div>',
  );

  $autoscrolling_widgets = array(NL_WIDGET_CAROUSEL, NL_WIDGET_HOR_ACCORDION);
  if (in_array($widget_type, $autoscrolling_widgets)) {
    $generic_autoscroll_delay = variable_get('ding_nodelist_' . $widget_type . '_delay', $default_conf['autoscroll_delay']);
    $form['ding_nodelist_wrapper']['widget_dependent']['autoscroll_delay'] = array(
      '#type' => 'textfield',
      '#title' => t('Delay (miliseconds)'),
      '#default_value' => !empty($conf['autoscroll_delay']) ? $conf['autoscroll_delay'] : $generic_autoscroll_delay,
      '#description' => t('Time in milliseconds an item will be shown before switching to the next one'),
      '#size' => 4,
    );
  }

  $form['ding_nodelist_wrapper']['override_title_text'] = array(
    '#type' => 'textfield',
    '#title' => t('List title'),
    '#description' => t('Enter a title to be shown above the list items. Leave empty to omit the title.')
    . ' ' . t('You may use %keywords from contexts, as well as %title to contain the original title.'),
    '#required' => FALSE,
    '#default_value' => isset($conf['override_title_text']) ? $conf['override_title_text'] : '',
  );

  // Manually controlled list.
  $form['ding_nodelist_wrapper']['nodelist_content'] = array(
    '#type' => 'fieldset',
    '#title' => t('Content'),
  );

  $form['ding_nodelist_wrapper']['nodelist_content']['list_type'] = array(
    '#type' => 'radios',
    '#options' => array(
      'custom-dynamic' => t('Custom / Dynamic'),
      'all' => t('All content'),
    ),
    '#default_value' => isset($conf['list_type']) ? $conf['list_type'] : 'all',
  );

  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper'] = array(
    '#type' => 'container',
    '#states' => array(
      'visible' => array(
        ':input[name=list_type]' => array('value' => 'custom-dynamic'),
      ),
    ),
  );

  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['nodes_switch'] = array(
    '#type' => 'checkbox',
    '#title' => t('Custom content?'),
    '#prefix' => '<hr />',
    '#default_value' => isset($conf['nodes_switch']) ? $conf['nodes_switch'] : 0,
  );

  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes'] = array(
    '#type' => 'container',
    '#collapsible' => FALSE,
    '#tree' => FALSE,
    '#title' => t('Custom item list'),
    '#collapsible' => FALSE,
    '#prefix' => '<div class="clear-block" id="ding_nodelist-wrapper">',
    '#suffix' => '</div>',
    '#states' => array(
      'invisible' => array(
        ':input[name=nodes_switch]' => array('checked' => FALSE),
      ),
    ),
  );

  // Render selected nodes.
  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes']['selected_nodes'] = array(
    '#prefix' => '<div id="ding_nodelist-selected-nodes">',
    '#suffix' => '</div>',
    '#theme' => '_ding_nodelist_items_table',
    '#tree' => TRUE,
  );

  $delta = 0;
  $weight = 0;
  $max_weight = $weight;
  $node_count = NULL;
  $filter_count = NULL;

  if (isset($form_state['values']['selected_nodes_count'])) {
    $node_count = $form_state['values']['selected_nodes_count'];
  }
  else {
    $node_count = empty($form_state['values']['selected_nodes']) ? 1 : count($form_state['values']['selected_nodes']);
  }

  if (!empty($conf['selected_nodes'])) {
    $delta = count($conf['selected_nodes']);
    foreach ($conf['selected_nodes'] as $key => $node) {
      $weight = $node['weight'];
      $max_weight = ($max_weight < $weight) ? $weight : $max_weight;
      $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes']['selected_nodes'][$key] = _ding_nodelist_selected_node($key, $node_type, $node, $weight);
    }
  }

  // Add new node field.
  $weight = ++$max_weight;
  for (; $delta < $node_count; $delta++) {
    $key = $delta;
    $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes']['selected_nodes'][$key] = _ding_nodelist_selected_node($key, $node_type, NULL, $weight);
  }

  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes']['add_node'] = array(
    // Used to identify the button in validate/submit handler(s).
    '#name' => 'add_node',
    '#parents' => array('ding_nodelist_nodes', 'add_node'),
    '#type' => 'submit',
    '#value' => t('Add content'),
    '#weight' => 1,
    '#submit' => array('ding_nodelist_add_node_submit'),
    '#limit_validation_errors' => array(array('selected_nodes')),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-selected-nodes',
      'callback' => 'ding_nodelist_js_add_node',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );

  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['dynamic_switch'] = array(
    '#type' => 'checkbox',
    '#title' => t('Dynamic content?'),
    '#prefix' => '<hr />',
    '#default_value' => isset($conf['dynamic_switch']) ? $conf['dynamic_switch'] : 0,
  );


  // Dynamic list settings.
  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic'] = array(
    '#type' => 'container',
    '#states' => array(
      'invisible' => array(
        ':input[name=dynamic_switch]' => array('checked' => FALSE),
      ),
    ),
  );

  // Render selected filters.
  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters'] = array(
    '#type' => 'container',
    '#prefix' => '<div id="ding_nodelist-taxonomy-filters">',
    '#suffix' => '</div>',
    '#theme' => '_ding_nodelist_filters_table',
    '#tree' => TRUE,
  );

  if (isset($form_state['values']['taxonomy_filters_count'])) {
    $filter_count = $form_state['values']['taxonomy_filters_count'];
  }
  else {
    $filter_count = empty($form_state['values']['taxonomy_filters']) ? 1 : count($form_state['values']['taxonomy_filters']);
  }

  // Retrieve vocabularies current CT references.
  $allowed_fields = array();
  $field_vocabulary = array();
  $fields = field_info_instances('node', $node_type);
  foreach ($fields as $field) {
    $field_config = field_info_field($field['field_name']);
    // Check if the field is a term reference field.
    if ($field_config['type'] == 'taxonomy_term_reference') {
      $allowed_fields[$field['field_name']] = $field['label'];
      $field_vocabulary[$field['field_name']] = $field_config['settings']['allowed_values'][0]['vocabulary'];
    }
  }

  // Check if filter vocabulary was changed.
  $changed_filter_id = NULL;
  if (!empty($form_state['triggering_element']) && isset($form_state['triggering_element']['#parents'][2])
    && $form_state['triggering_element']['#parents'][2] == 'filter_field') {
    $changed_filter_id = $form_state['triggering_element']['#parents'][1];
    $changed_filter = $form_state['values']['taxonomy_filters'][$changed_filter_id];

    // Update auto-complete, preserve other fields.
    $filter['filter_field'] = $changed_filter['filter_field'];
    $filter['filter_vocab'] = $field_vocabulary[$filter['filter_field']];

    // Important: delete old input!
    unset($form_state['input']['taxonomy_filters'][$changed_filter_id]);
    $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters'][$changed_filter_id] = _ding_nodelist_taxonomy_filter($allowed_fields, $filter, $changed_filter_id);
  }

  $delta = 0;

  if (!empty($conf['taxonomy_filters'])) {
    $delta = count($conf['taxonomy_filters']);
    foreach ($conf['taxonomy_filters'] as $key => $filter) {
      // Skip just changed filter.
      if ($changed_filter_id === $key) {
        continue;
      }

      $tags = array();
      foreach ($filter['filter_terms'] as $tid) {
        $tags[$tid] = taxonomy_term_load($tid);
      }
      $filter['filter_terms'] = taxonomy_implode_tags($tags);
      $filter['filter_vocab'] = $field_vocabulary[$filter['filter_field']];
      $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters'][$key] = _ding_nodelist_taxonomy_filter($allowed_fields, $filter, $key);
    }

    ksort($form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters']);
  }

  // Add new filter field.
  for (; $delta < $filter_count; $delta++) {
    $key = $delta;
    if ($changed_filter_id === $key) {
      continue;
    }

    // Set default field value.
    $first_field = array_shift(array_keys($allowed_fields));
    $filter = array(
      'filter_field' => $first_field,
      'filter_vocab' => $field_vocabulary[$first_field],
    );
    $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters'][$key] = _ding_nodelist_taxonomy_filter($allowed_fields, $filter, $key);
  }

  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['add_filter'] = array(
    '#name' => 'add_filter',
    '#type' => 'submit',
    '#value' => t('Add filter'),
    '#weight' => 0,
    '#submit' => array('ding_nodelist_add_filter_submit'),
    '#limit_validation_errors' => array(array('taxonomy_filters')),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-taxonomy-filters',
      'callback' => 'ding_nodelist_js_add_filter',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );

  // Date field filtering.
  // @todo: remove hard code and make more unversal.
  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['content_filter_date'] = array(
    '#type' => $node_type == 'ding_event' ? 'checkbox' : 'hidden',
    '#title' => t('Show upcoming events only'),
    '#description' => t('If checked only future events will be shown'),
    '#default_value' => $node_type == 'ding_event' && isset($conf['content_filter_date']) ? $conf['content_filter_date'] : FALSE,
    '#prefix' => '<div id="ding_nodelist-content-filter-date">',
    '#suffix' => '</div>',
  );

  // Content filter.
  $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['content_filter_promoted'] = array(
    '#type' => 'checkbox',
    '#title' => t('Show "Promoted to front page" content only'),
    '#default_value' => isset($conf['content_filter_promoted']) ? $conf['content_filter_promoted'] : FALSE,
  );

  // Various options.
  $form['ding_nodelist_wrapper']['nodelist_various_settings'] = array(
    '#type' => 'fieldset',
    '#title' => t('Various'),
  );

  // Initialize drop-down array's values.
  $options = array(0 => 'none')
  + array_combine(range(1, 25), range(1, 25))
  + array_combine(range(30, 50, 5), range(30, 50, 5))
  + array_combine(range(50, 100, 10), range(50, 100, 10));

  $form['ding_nodelist_wrapper']['nodelist_various_settings']['limit'] = array(
    '#type' => 'select',
    '#title' => t('Item limit'),
    '#default_value' => isset($conf['limit']) ? $conf['limit'] : $default_conf['limit'],
    '#options' => $options,
    '#description' => t('Limit amount of items displayed. This value is used only for Dynamic and All content displays.'),
    '#states' => array(
      'invisible' => array(
        ':input[name=nodes_switch]' => array('checked' => TRUE),
        ':input[name=dynamic_switch]' => array('checked' => FALSE),
      ),
      'visible' => array(
        ':input[name=list_type]' => array(
          array('value' => 'custom-dynamic'),
          array('value' => 'all'),
        ),
      ),
    ),
  );

  $form['ding_nodelist_wrapper']['nodelist_various_settings']['ding_nodelist_sorting'] = array(
    '#type' => 'container',
  );

  $sort_options = array(
    'created' => t('Creation date'),
    'title' => t('Title'),
    'sticky' => t('Sticky first'),
  );

  if ($node_type == 'ding_event') {
    $sort_options['event_date'] = t('Event date');
  }

  $form['ding_nodelist_wrapper']['nodelist_various_settings']['ding_nodelist_sorting']['sort_field'] = array(
    '#type' => 'select',
    '#title' => t('Sort by'),
    '#options' => $sort_options,
    '#empty_option' => t('No sorting'),
    '#default_value' => isset($conf['sort_field']) ? $conf['sort_field'] : '',
    '#prefix' => '<div id="ding_nodelist-sort-field">',
    '#suffix' => '</div>',
  );

  $sort_order = isset($conf['sort_order']) ? $conf['sort_order'] : '';
  $form['ding_nodelist_wrapper']['nodelist_various_settings']['ding_nodelist_sorting']['sort_order'] = array(
    '#type' => 'select',
    '#title' => t('Sorting order'),
    '#options' => array(
      'asc' => t('Ascending'),
      'desc' => t('Descending'),
    ),
    '#default_value' => $sort_order,
    '#states' => array(
      // Hide the settings when the sorting order is not applicable.
      'invisible' => array(
        ':input[name="sort_field"]' => array(array('value' => ''), array('value' => 'sticky')),
      ),
    ),
  );

  $form['ding_nodelist_wrapper']['nodelist_various_settings']['columns'] = array(
    '#type' => 'select',
    '#title' => t('Width (columns)'),
    '#options' => array(
      NL_COL_FULL => t('Full width'),
      NL_COL_HALF => '1/2',
      NL_COL_THIRD => '1/3',
      NL_COL_QRT => '1/4',
    ),
    '#default_value' => isset($conf['columns']) ? $conf['columns'] : $default_conf['columns'],
  );

  // Forms for Bottom settings.
  $form['ding_nodelist_wrapper']['ding_nodelist_bottom_links'] = array(
    '#type' => 'fieldset',
    '#title' => t('Bottom links'),
    '#collapsible' => FALSE,
    '#description' => t('List of "read more" links.'),
  );

  // Container for bottom links
  $form['ding_nodelist_wrapper']['ding_nodelist_bottom_links']['more_links'] = array(
    '#prefix' => '<div id="ding_nodelist-more-link">',
    '#suffix' => '</div>',
    '#theme' => '_ding_nodelist_links_table',
    '#tree' => TRUE,
  );

  // Get all bottom links.
  $delta = 0;

  if (isset($form_state['values']['bottom_links_count'])) {
    $links_count = $form_state['values']['bottom_links_count'];
  }
  else {
    $links_count = empty($form_state['values']['more_links']) ? 1 : count($form_state['values']['more_links']);
  }

  if (isset($conf['more_links'])) {
    $delta = count($conf['more_links']);
    foreach ($conf['more_links'] as $key => $link) {
      $form['ding_nodelist_wrapper']['ding_nodelist_bottom_links']['more_links'][$key] = _ding_nodelist_links_form($key, $link);
    }
  }

  // Add new bottom link field.
  for ($delta; $delta < $links_count; $delta++) {
    $key = $delta;
    $form['ding_nodelist_wrapper']['ding_nodelist_bottom_links']['more_links'][$key] = _ding_nodelist_links_form($key, NULL);
  }

  $form['ding_nodelist_wrapper']['ding_nodelist_bottom_links']['ding_bottom_links_more'] = array(
    '#type' => 'submit',
    '#value' => t('Add more link'),
    '#submit' => array('ding_nodelist_add_bottom_link_submit'),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-more-link',
      'callback' => 'ding_nodelist_js_add_links',
      'effect' => 'fade',
      'method' => 'replace',
    ),
  );

  // Cache settings.
  $form['ding_nodelist_wrapper']['cache_settings'] = array(
    '#type' => 'fieldset',
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#tree' => FALSE,
    '#title' => t('Cache settings'),
  );

  // Load cache settigns and prepare form.
  if (user_access('nodelist cache settings')) {
    ctools_include('plugins');
    $simple_cache_plugin = ctools_plugin_get_info('panels', 'cache');
    ctools_plugin_load_includes($simple_cache_plugin);
    $pane = $form_state['pane'];
    $settings = !empty($pane->cache['settings'])
      ? $pane->cache['settings']
      : array(
        'lifetime' => variable_get('ding_nodelist_cache_default_time', NL_CACHE_LIFETIME),
        'granularity' => 'context',
      );
    $cache_form = panels_simple_cache_settings_form($settings, $form_state['display'], $pane->pid);
    // @todo: Granularity is forced to 'context' now.
    unset($cache_form['granularity']);
    $form['ding_nodelist_wrapper']['cache_settings'] = array_merge($form['ding_nodelist_wrapper']['cache_settings'], $cache_form);
  }


  // Restore other form elements if this is not the first form display.
  if (isset($form_state['restore'])) {
    $form = array_merge($form_state['original_form'], $form);
  }

  // Remove some standard controls.
  unset($form['override_title']);
  unset($form['override_title_text']);
  unset($form['override_title_markup']);

  return $form;
}

/**
 * Generate a form piece for dynamic node select form.
 *
 * @param string $key
 *   Unique key for this piece.
 * @param string $type
 *   Node type.
 * @param array $node
 *   Array with the node oject.
 * @param int $weight
 *   Piece weight.
 * @return array
 *   Form structure.
 */
function _ding_nodelist_selected_node($key, $type, $node = NULL, $weight = 0) {
  $form = array(
    '#tree' => TRUE,
    '#weight' => $weight,
  );

  // Set default value for 'node'
  $node_default = (!is_null($node) && isset($node['node'])) ? $node['node'] : '';
  $form['node'] = array(
    '#type' => 'textfield',
    '#title' => t('Select new node to add to list'),
    '#title_display' => 'invisible',
    '#autocomplete_path' => 'ding_nodelist/autocomplete/' . $type,
    '#parents' => array('selected_nodes', $key, 'node'),
    '#default_value' => $node_default,
  );

  $form['nid'] = array(
    '#type' => 'value',
    '#value' => NULL,
    '#parents' => array('selected_nodes', $key, 'nid'),
  );

  // Set default value for 'nid' if not empty field
  if (!is_null($node) && isset($node['nid']) && ctype_digit($node['nid'])) {
    $form['nid']['#value'] = $node['nid'];
  }
  elseif (!is_null($node) && isset($node['node'])) {
    $tmp_node = explode(':', $node['node']); // EXPERIMENTAL FIX! previous value '$node' gave warnings.
    $tmp_node = array_pop($tmp_node);
    $tmp_node = substr($tmp_node, 0, -1);
    if (ctype_digit($tmp_node)) {
      $node['nid'] = $tmp_node;
    }
  }

  $form['type'] = array(
    '#type' => 'value',
    '#value' => $type,
    '#parents' => array('selected_nodes', $key, 'type'),
  );

  $form['weight'] = array(
    '#type' => 'weight',
    '#title' => $node['nid'] !== '' ? t('Weight for node @label', array('@label' => $node['nid'])) : t('Weight for new choice'),
    '#title_display' => 'invisible',
    '#default_value' => $weight,
    '#delta' => 50,
    '#parents' => array('selected_nodes', $key, 'weight'),
  );


  $form['node_delete_' . $key] = array(
    '#name' => 'node_delete_' . $key,
    '#type' => 'submit',
    '#title_display' => 'invisible',
    '#value' => t('Delete'),
    '#parents' => array('selected_nodes', $key, 'node_delete_' . $key),
    '#submit' => array('ding_nodelist_node_delete_submit'),
    '#limit_validation_errors' => array(),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-selected-nodes',
      'callback' => 'ding_nodelist_js_add_node',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );
  return $form;
}

/**
 * Builds more link form.
 */
function _ding_nodelist_links_form($key, $link) {
  $form = array(
    '#tree' => TRUE,
    '#weight' => $key,
  );

  $form['text'] = array(
    '#type' => 'textfield',
    '#title' => t('Link title'),
    '#title_display' => 'invisible',
    '#size' => 20,
    '#tree' => TRUE,
    '#weight' => -1,
    '#parents' => array('more_links', $key, 'text'),
    '#default_value' => (!empty($link['text'])) ? $link['text'] : '',
  );

  $form['links'] = array(
    '#type' => 'textfield',
    '#title' => t('URL'),
    '#title_display' => 'invisible',
    '#required' => FALSE,
    '#description' => check_plain(t('Local path or external URL starting with http(s). Enter "<front>" to link to home page.')),
    '#parents' => array('more_links', $key, 'links'),
    '#default_value' => (!empty($link['links'])) ? $link['links'] : '',
  );

  return $form;
}

/**
 * Builds filter form.
 */
function _ding_nodelist_taxonomy_filter($fields, $filter, $key) {
  $form = array(
    '#tree' => TRUE,
    '#weight' => $key,
  );

  $form['filter_field'] = array(
    '#type' => 'select',
    '#title_display' => 'invisible',
    '#options' => $fields,
    '#default_value' => !is_null($filter) && !empty($filter['filter_field']) ? $filter['filter_field'] : '',
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-taxonomy-filters',
      'callback' => 'ding_nodelist_js_add_filter',
      'method' => 'replace',
      'effect' => 'fade',
    ),
    '#parents' => array('taxonomy_filters', $key, 'filter_field'),
  );

  $form['filter_terms'] = array(
    '#vocabulary_name' => $filter['filter_vocab'],
    '#type' => 'textfield',
    '#title_display' => 'invisible',
    '#default_value' => !is_null($filter) && !empty($filter['filter_terms']) ? $filter['filter_terms'] : '',
    '#parents' => array('taxonomy_filters', $key, 'filter_terms'),
    '#maxlength' => 1024,
    '#element_validate' => array('_ding_nodelist_taxonomy_autocomplete_validate'),
    '#autocomplete_path' => !is_null($filter) && !empty($filter['filter_field']) ? 'taxonomy/autocomplete/' . $filter['filter_field'] : NULL,
  );

  $form['filter_delete_' . $key] = array(
    '#name' => 'filter_delete_' . $key,
    '#type' => 'submit',
    '#title_display' => 'invisible',
    '#value' => t('Delete'),
    '#parents' => array('taxonomy_filters', $key, 'filter_delete_' . $key),
    '#submit' => array('ding_nodelist_filter_delete_submit'),
    '#limit_validation_errors' => array(),
    '#ajax' => array(
      'wrapper' => 'ding_nodelist-taxonomy-filters',
      'callback' => 'ding_nodelist_js_add_filter',
      'method' => 'replace',
      'effect' => 'fade',
    ),
  );

  return $form;
}

/**
 * Custom submit function to add more choices.
 */
function ding_nodelist_add_node_submit($form, &$form_state) {
  // Add new node to list.
  $form_state['values']['selected_nodes_count'] = count($form_state['values']['selected_nodes']) + 1;
  unset($form_state['input']['selected_nodes']);
  foreach ($form_state['values']['selected_nodes'] as $key => $node) {
    if (!empty($node['node'])) {
      $tmp_nid = explode(':', $node['node']);
      $tmp_nid = array_pop($tmp_nid);
      $tmp_nid = substr($tmp_nid, 0, -1);
      // TODO: Implement more complex check for given title + ID
      if (ctype_digit($tmp_nid)) {
        $form_state['values']['selected_nodes'][$key]['nid'] = $tmp_nid;
      }
    }
  }

  // Copy 'input' since limit_validation_errors empties 'values'.
  $form_state['values'] += $form_state['input'];
  _ding_nodelist_content_type_form_save($form_state, TRUE);
}

/**
 * Custom submit function for adding more filters.
 */
function ding_nodelist_add_filter_submit($form, &$form_state) {
  // Add new filter.
  $form_state['values']['taxonomy_filters_count'] = count($form_state['values']['taxonomy_filters']) + 1;

  // Copy 'input' since limit_validation_errors empties 'values'.
  $form_state['values'] += $form_state['input'];
  _ding_nodelist_content_type_form_save($form_state, TRUE);
}

/**
 * Custom submit function for filter deletion.
 */
function ding_nodelist_filter_delete_submit($form, &$form_state) {

  $deleted_filter = $form_state['triggering_element']['#parents'][1];
  unset($form_state['values']['taxonomy_filters'][$deleted_filter]);
  unset($form_state['input']['taxonomy_filters'][$deleted_filter]);

  // Re-index after deletion and save.
  $form_state['input']['taxonomy_filters'] = array_values($form_state['input']['taxonomy_filters']);
  $form_state['values'] = $form_state['input'];
  _ding_nodelist_content_type_form_save($form_state, TRUE);
}

/**
 * Custom submit function for filter deletion.
 */
function ding_nodelist_node_delete_submit($form, &$form_state) {
  $deleted_node = $form_state['triggering_element']['#parents'][1];
  unset($form_state['values']['selected_nodes'][$deleted_node]);
  unset($form_state['input']['selected_nodes'][$deleted_node]);

  // Re-index after deletion and save.
  $form_state['input']['selected_nodes'] = array_values($form_state['input']['selected_nodes']);
  $form_state['values'] = $form_state['input'];
  _ding_nodelist_content_type_form_save($form_state, TRUE);
}

/**
 * Custom submit function for adding more links.
 */
function ding_nodelist_add_bottom_link_submit(&$form, &$form_state) {
  // Add new link to list.
  $form_state['values']['bottom_links_count'] = count($form_state['values']['more_links']) + 1;
  unset($form_state['input']['more_links']);

  // Saving all the values of the form.
  _ding_nodelist_content_type_form_save($form_state, TRUE);
}

/**
 * Edit form validation function.
 */
function ding_nodelist_content_type_edit_form_validate($form, &$form_state) {
  $form_state['restore'] = TRUE;

  // Do not validate if filter was changed or deleted.
  $te = empty($form_state['triggering_element']) ? NULL : $form_state['triggering_element'];
  if (strpos($te['#name'], 'widget_type') === 0 || $te['#name'] == 'filter_field') {
    return;
  }

  $list_type = $form_state['values']['list_type'];
  if ($list_type === 'custom-dynamic') {
    $node_switch = isset($form_state['values']['nodes_switch']) ? $form_state['values']['nodes_switch'] : 0;
    $dynamic_switch = isset($form_state['values']['dynamic_switch']) ? $form_state['values']['dynamic_switch'] : 0;

    if (!$node_switch && !$dynamic_switch) {
      form_set_error('', t('Select at least one content pick rule (custom and/or dynamic).'));
    }
    else {
      // Check for empty nodes.
      //$no_custom_content = FALSE;
      if (!empty($form_state['values']['selected_nodes']) && $form_state['values']['nodes_switch']) {
        $node_cnt = count($form_state['values']['selected_nodes']);
        foreach ($form_state['values']['selected_nodes'] as $key => $node) {
          if ($te['#name'] == 'add_node' || $te['#value'] === 'Finish' || $node_cnt > 1) {
            if (empty($node['node'])) {
              form_set_error("selected_nodes][$key", t('No custom list content specified.'));
            }
          }
        }
      }

      // Check for empty filters.
      if (!empty($form_state['values']['taxonomy_filters']) && $form_state['values']['dynamic_switch']) {
        $filter_cnt = count($form_state['values']['taxonomy_filters']);
        foreach ($form_state['values']['taxonomy_filters'] as $key => $filter) {
          if ($te['#name'] == 'add_filter' || $te['#value'] === 'Finish' || $filter_cnt > 1) {
            if (empty($filter['filter_terms'])) {
              form_set_error("taxonomy_filters][$key][filter_terms", t('No terms specified for dynamic list filter.'));
            }
          }
        }
      }
    }
  }

  // Check if the link is valid.
  foreach ($form_state['values']['more_links'] as $key => &$bottom) {
    if (!empty($bottom['text']) || !empty($bottom['links'])) {
      if (!_ding_nodelist_is_valid_link($bottom['links'])) {
        form_set_error("more_links][$key][links", t('Invalid local or external link.'
            . ' External links must begin with "http" or "https", local links should point to existing pages.'));
      }
    }
  }
}

/**
 * Edit form submit function.
 */
function ding_nodelist_content_type_edit_form_submit($form, &$form_state) {

  // Removing empty nodes.
  if (!empty($form_state['values']['selected_nodes'])) {
    foreach ($form_state['values']['selected_nodes'] as $key => $node) {
      if (empty($node['node'])) {
        unset($form_state['values']['selected_nodes'][$key]);
      }
      else {
        $tmp_nid = explode(':', $node['node']);
        $tmp_nid = array_pop($tmp_nid);
        $tmp_nid = substr($tmp_nid, 0, -1);
        // TODO: Implement more complex check for correct title of the given ID
        if (ctype_digit($tmp_nid)) {
          $form_state['values']['selected_nodes'][$key]['nid'] = $tmp_nid;
        }
      }
    }
  }

  // Removing empty filters.
  if (!empty($form_state['values']['taxonomy_filters'])) {
    foreach ($form_state['values']['taxonomy_filters'] as $key => $filter) {
      if (empty($filter['filter_terms'])) {
        unset($form_state['values']['taxonomy_filters'][$key]);
      }
    }
  }

  // Check if there are any empty links.
  if (!empty($form_state['values']['more_links'])) {
    foreach ($form_state['values']['more_links'] as $key => &$bottom) {
      if (empty($bottom['text']) || empty($bottom['links'])) {
        unset($form_state['values']['more_links'][$key]);
      }
      // Trim slashes.
      $bottom['links'] = ltrim($bottom['links'], '/');
    }
  }

  // Anything in $form_state['conf'] will be saved automatically.
  _ding_nodelist_content_type_form_save($form_state);
}

/**
 * Ajax handler of content type select box.
 * Returns multiple commands.
 */
function ding_nodelist_js($form, &$form_state) {
  return array(
    '#type' => 'ajax',
    '#commands' => array(
      ajax_command_replace('#ding_nodelist-selected-nodes', drupal_render($form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes']['selected_nodes'])),
      ajax_command_replace('#ding_nodelist-taxonomy-filters', drupal_render($form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters'])),
      ajax_command_replace('.form-item-widget-type', drupal_render($form['ding_nodelist_wrapper']['widget_type'])),
      ajax_command_replace('#ding_nodelist-content-filter-date', drupal_render($form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['content_filter_date'])),
      ajax_command_replace('#ding_nodelist-sort-field', drupal_render($form['ding_nodelist_wrapper']['nodelist_various_settings']['ding_nodelist_sorting']['sort_field'])),
    ),
  );
}

/**
 * Ajax handler of bottom links actions.
 */
function ding_nodelist_js_add_links($form, &$form_state) {
  return $form['ding_nodelist_wrapper']['ding_nodelist_bottom_links']['more_links'];
}

/**
 * Ajax handler for custom nodes actions.
 */
function ding_nodelist_js_add_node($form, &$form_state) {
  return $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_nodes']['selected_nodes'];
}

/**
 * Ajax handler of taxonomy filter actions.
 */
function ding_nodelist_js_add_filter($form, &$form_state) {
  return $form['ding_nodelist_wrapper']['nodelist_content']['nodelist_content_wrapper']['ding_nodelist_dynamic']['taxonomy_filters'];
}

/**
 * Ajax handler of widget type select box.
 * Returns eligible item templates based on configuration.
 */
function ding_nodelist_js_template($form, &$form_state) {
  return $form['ding_nodelist_wrapper']['widget_dependent'];
}

/**
 * Autocomplete function that gives the available nodes.
 */
function ding_nodelist_autocomplete($type, $title = '') {
  $nodes = array();

  // Fetch all published nodes.
  $nodes = db_select('node', 'n')
    ->fields('n', array('nid', 'title'))
    ->condition('n.type', $type)
    ->condition('n.title', "%$title%", 'LIKE')
    ->condition('n.status', NODE_PUBLISHED)
    ->execute()
    ->fetchAllKeyed();

  // Make a beatifull select.
  $formatted_result = array();
  foreach ($nodes as $nid => $title) {
    $formatted_result[$title . " [nid:$nid]"] = $title;
  }

  drupal_json_output($formatted_result);
}

/**
 * Implements hook_theme().
 */
function ding_nodelist_theme($existing, $type, $theme, $path) {
  // Do not rely on path - it may be unknown to module_invoke_all caller.
  $path = drupal_get_path('module', 'ding_nodelist') . '/templates';

  $themes = array(
    // Configuration form templates.
    '_ding_nodelist_items_table' => array(
      'render element' => 'form',
    ),
    '_ding_nodelist_filters_table' => array(
      'render element' => 'form',
    ),
    '_ding_nodelist_links_table' => array(
      'render element' => 'form',
    ),
    '_ding_nodelist_templates_table' => array(
      'render element' => 'form',
    ),
    // Widget templates.
    '_ding_nodelist_widget_simple' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_simple',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
    '_ding_nodelist_widget_single' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_single',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
    '_ding_nodelist_widget_horizontal_accordion' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_horizontal_accordion',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
    '_ding_nodelist_widget_vertical_accordion' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_vertical_accordion',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
    '_ding_nodelist_widget_carousel' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_carousel',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
    '_ding_nodelist_widget_slider' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_slider',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
    '_ding_nodelist_widget_taxonomy' => array(
      'path' => $path,
      'template' => 'ding_nodelist_widget_taxonomy',
      'variables' => array(
        'items' => NULL,
        'template' => NULL,
        'links' => NULL,
        'conf' => NULL,
      ),
    ),
  );

  // Automatically register core templates.
  $templates = _ding_nodelist_get_core_templates();
  foreach ($templates as $template_name => $template) {
    $themes[$template_name] = array(
      'path' => $path,
      'template' => $template_name,
      'variables' => array(
        'item' => NULL,
        'conf' => NULL,
      ),
    );
  }

  return $themes;
}

/**
 * Helper theming function.
 */
function theme__ding_nodelist_items_table($variables) {
  $form = $variables['form'];
  $rows = array();
  $headers = array('', t('Selected content'), t('Weight'), '');

  foreach (element_children($form) as $key) {
    // Set special classes for drag and drop updating.
    $form[$key]['weight']['#attributes']['class'] = array('ding_nodelist-weight');

    // Build the table row.
    $row = array(
      'data' => array(
        array('class' => array('choice-flag')),
        drupal_render($form[$key]['node']),
        drupal_render($form[$key]['weight']),
        drupal_render($form[$key]['node_delete_' . $key]),
      ),
      'class' => array('draggable'),
    );

    // Add any additional classes set on the row.
    if (!empty($form[$key]['#attributes']['class'])) {
      $row['class'] = array_merge($row['class'], $form[$key]['#attributes']['class']);
    }

    $rows[] = $row;
  }

  drupal_add_tabledrag('ding_nodelist-selected-table', 'order', 'sibling', 'ding_nodelist-weight');

  $output = theme('table', array('header' => $headers, 'rows' => $rows, 'attributes' => array('id' => 'ding_nodelist-selected-table')));
  $output .= drupal_render_children($form);
  return $output;
}

/**
 * Helper theming function.
 */
function theme__ding_nodelist_filters_table($variables) {
  $form = $variables['form'];

  $rows = array();
  $header = array(t('Field'), t('Values'), '');

  foreach (element_children($form) as $key) {
    // Build the table row.
    $row = array(
      'data' => array(
        drupal_render($form[$key]['filter_field']),
        drupal_render($form[$key]['filter_terms']),
        drupal_render($form[$key]['filter_delete_' . $key]),
      ),
    );

    $rows[] = $row;
  }

  $output = theme('table', array('header' => $header, 'rows' => $rows, 'attributes' => array('id' => 'ding_nodelist-filters-table')));
  $output .= drupal_render_children($form);
  return $output;
}

/**
 * Helper theming function.
 */
function theme__ding_nodelist_links_table($variables) {
  $form = $variables['form'];
  $rows = array();
  $header = array(t('Text'), t('URL'));

  foreach (element_children($form) as $key) {
    // Build the table row.
    $row = array(
      'data' => array(
        drupal_render($form[$key]['text']),
        drupal_render($form[$key]['links']),
      ),
    );

    $rows[] = $row;
  }

  $output = theme('table', array('header' => $header, 'rows' => $rows, 'attributes' => array('id' => 'ding_nodelist-links-table')));
  $output .= drupal_render_children($form);
  return $output;
}

/**
 * Theme function to render the backend list of templates.
 */
function theme__ding_nodelist_templates_table($variables) {
  $header = array(
    t('Machine name'),
    t('Title'),
    t('Content type'),
    t('List type'),
    t('Visible'),
  );
  $rows = array();
  $form = $variables['form'];
  foreach (element_children($form) as $key) {
    $rows[] = array(
      $form[$key]['template_name']['#value'],
      drupal_render($form[$key]['title']),
      drupal_render($form[$key]['content_type']),
      drupal_render($form[$key]['widget']),
      drupal_render($form[$key]['visible']),
    );
  }

  return theme('table', array('header' => $header, 'rows' => $rows)) . drupal_render_children($form);
}

/**
 * Ctools admin view pane's title.
 */
function ding_nodelist_content_type_admin_title($subtype, $conf, $context = NULL) {
  if (!empty($conf['override_title_text'])) {
    $output = t('Nodelist') . ': ' . filter_xss_admin($conf['override_title_text']);
  }
  else {
    $output = t('Nodelist (untitled)');
  }
  return $output;
}

/**
 * Callback to provide administrative info (the preview in panels when building a panel).
 */
function ding_nodelist_content_type_admin_info($subtype, $conf, $context = NULL) {
  // @todo: show details about nodelist configuration here.
  $block->title = t('No information');
  $info = '';
  $block->content = $info;
  return $block;
}

/**
 * Run-time rendering of the body of the list.
 *
 * @param $subtype
 *   Content type sub-type
 * @param $conf
 *   Configuration as done at admin time.
 * @param $args
 *   Special arguments to use.
 * @param $context
 *  Possible context details.
 *
 * @return
 *   An object with at least title and content members.
 */
function ding_nodelist_content_type_render($subtype, $conf, $args, $context) {

  $block = new stdClass();

  // Prepare classes for widget container.
  $columns = $conf['columns'];
  $classes = array();
  $classes[] = 'ding_nodelist';
  $classes[] = 'ding_nodelist-' . $conf['widget_type'];
  $classes[] = 'ding_nodelist-col-' . $columns;
  $classes[] = $conf['unique_id'];

  // Build title
  $title = NULL;
  if (!empty($conf['override_title_text'])) {
    $title = check_plain($conf['override_title_text']);
  }

  // Create proper layout for variable-width lists.
  $map = _ding_nodelist_get_column_map();
  $columns_layout = &drupal_static('ding_nodelist_cols', 0);
  if (!$columns_layout) {
    $classes[] = 'ding_nodelist-col-first';
    $columns_layout += $map[$columns];
  }
  else {
    // Maximum of 4 sub-columns is reached.
    $expected_width = $columns_layout + $map[$columns];
    if ($expected_width == 1) {
      $classes[] = 'ding_nodelist-col-last';
      $columns_layout = 0;
    }
    else {
      $columns_layout += $map[$columns];
    }
  }

  // Load default CSS.
  drupal_add_css(drupal_get_path('module', 'ding_nodelist') . '/css/ding_nodelist.css', 'file');

  // Fetch content IDs.
  $nodes = _ding_nodelist_get_custom_list_nodes($conf);

  // Check if dynamic nodes must be loaded
  $custom_content = !empty($conf['selected_nodes']);
  $dynamic_content = !empty($conf['taxonomy_filters']);
  $only_custom_content = (($custom_content == TRUE) && ($dynamic_content == FALSE)) ? TRUE : FALSE;
  if (!$only_custom_content) {
    $nodes = array_merge($nodes, _ding_nodelist_get_dynamic_list_nodes($conf));
  }

  // Load items by their IDs.
  $nodes = node_load_multiple($nodes);

  // Remove elements if they are of type carousel, single item, vertical
  // accordion or horizontal accordion and do not contain list image.
  if (in_array($conf['widget_type'], array('single', 'carousel', 'horizontal_accordion', 'vertical_accordion'))) {
   foreach ($nodes as $key => $node) {
     if (count($node->field_list_image) <= 0) {
       unset($nodes[$key]);
     }
   }
  }

  // Apply sorting.
  $nodes = _ding_nodelist_sort_nodes($nodes, $conf);

  $nodes = _ding_nodelist_striptags($nodes);

  // Init JS for widgets
  _ding_nodelist_add_js($conf['widget_type'], $conf['autoscroll_delay'], $conf['unique_id']);
  $image_style = _ding_nodelist_init_image_style($conf['widget_type']);
  $theme_func = '_ding_nodelist_widget_' . $conf['widget_type'];
  $block->content = theme($theme_func, array(
    'items' => $nodes,
    'template' => $conf['item_template'],
    'links' => $conf['more_links'],
    'conf' => array(
      'title' => $title,
      'classes' => join(' ', $classes),
      'image_style' => $image_style,
    ),
  ));

  return $block;
}

/**
 * Add required JS libraries and initialization scripts to run widgets.
 * @param string $widget
 *   Widget type.
 * @param int $autoscroll_delay
 *   Animated widgets step delay.
 * @param int $unique_id
 *   Widget identifier.
 */
function _ding_nodelist_add_js($widget, $autoscroll_delay = NULL, $unique_id = NULL) {
  $mod_path = drupal_get_path('module', 'ding_nodelist');
  // Adding required JS libs
  switch ($widget) {
    case NL_WIDGET_CAROUSEL:
    case NL_WIDGET_SLIDER:
      drupal_add_js($mod_path . '/js/jquery.carouFredSel-5.5.0-packed.js', 'file');
      break;
    case NL_WIDGET_HOR_ACCORDION:
      drupal_add_js($mod_path . '/js/jquery.easing.1.3.js', 'file');
      drupal_add_js($mod_path . '/js/jquery.zaccordion.min.js', 'file');
      break;
    case NL_WIDGET_VER_ACCORDION:
      drupal_add_js($mod_path . '/js/jquery.easing.1.3.js', 'file');
      drupal_add_js($mod_path . '/js/jquery.vaccordion.js', 'file');
      break;
  }

  // Adding JS widget init stuff
  switch ($widget) {
    case NL_WIDGET_CAROUSEL:
      drupal_add_js(array('ding_nodelist' => array($unique_id => $autoscroll_delay)), 'setting');
      drupal_add_js($mod_path . '/js/carousel.js', 'file');
      break;
    case NL_WIDGET_SLIDER:
      drupal_add_js(array('ding_nodelist' => array($unique_id => $autoscroll_delay)), 'setting');
      drupal_add_js($mod_path . '/js/slider.js', 'file');
      break;
    case NL_WIDGET_HOR_ACCORDION:
      drupal_add_js(array('ding_nodelist' => array($unique_id => $autoscroll_delay)), 'setting');
      drupal_add_js($mod_path . '/js/haccordion.js', 'file');
      break;
    case NL_WIDGET_VER_ACCORDION:
      drupal_add_js(array('ding_nodelist' => array($unique_id => $autoscroll_delay)), 'setting');
      drupal_add_js($mod_path . '/js/vaccordion.js', 'file');
      break;
  }
}

/**
 * Init image styles based on widget and region.
 *
 * @param string $widget
 *   Widget type.
 *
 * @return string
 *   Image style name.
 */
function _ding_nodelist_init_image_style($widget) {
  // Init image_styles for region
  switch ($widget) {
    case NL_WIDGET_HOR_ACCORDION:
    case NL_WIDGET_CAROUSEL:
    case NL_WIDGET_SINGLE:
    case NL_WIDGET_VER_ACCORDION:
      return 'ding_nodelist_medium';

    case NL_WIDGET_TAXONOMY_LIKE:
    case NL_WIDGET_SLIDER:
      return 'ding_large';

    default:
      return '';
  }
}

/**
 * Returns the most up-to-date list of nodelist templates.
 * @param boolean
 *   Include or not hidden templates in return array.
 * @return array
 *   Found nodelist template details.
 */
function _ding_nodelist_get_templates($include_hidden = TRUE, $content_type = NULL, $widget_type = NULL) {
  static $templates = array();

  if (!empty($templates)) {
    return $templates;
  }

  // Fetch templates declared by this and other modules hook_theme function.
  // @todo: menu_block is known to cause issues on this call in PHP 5.3.x.
  foreach (module_invoke_all('theme', array(), NULL, NULL, NULL) as $template_name => $template) {
    if (strpos($template_name, 'ding_nodelist') === 0) {
      $templates[$template_name] = array(
        'filename' => $template_name,
      );
    }
  }

  // Add core file templates.
  $templates = array_merge($templates, _ding_nodelist_get_core_templates());

  $db_templates = db_select('ding_nodelist_templates', 'dnt')
    ->fields('dnt')
    ->execute()
    ->fetchAllAssoc('filename', PDO::FETCH_ASSOC);
  $db_template_names = array_keys($db_templates);

  // Register new templates.
  foreach ($templates as $template_name => $template) {
    if (!in_array($template_name, $db_template_names)) {
      $tpl_record = array(
        'filename' => $template_name,
        'title' => $template_name,
        'status' => NL_TPL_HIDDEN, // @todo: show nodelist's native templates by default?
      );
      try {
        db_insert('ding_nodelist_templates')->fields($tpl_record)->execute();
      }
      catch (Exception $e) {
        // @todo: show errors when template name duplicates an existing.
      }
    }
  }

  // Second, collect templates from db and find the common list.
  $db_templates = db_select('ding_nodelist_templates', 'dnt')
    ->fields('dnt')
    ->execute()
    ->fetchAllAssoc('filename', PDO::FETCH_ASSOC);

  foreach ($db_templates as $template_name => $template) {
    // Do not include hidden templates.
    if (!$include_hidden) {
      if ($template['status'] == NL_TPL_HIDDEN) {
        unset($templates[$template_name]);
        continue;
      }
    }

    if (isset($templates[$template_name])) {
      // Fetch content type from filename.
      $ct_name = explode('.', $template_name);

      // Filter by CT.
      if (!$content_type || ($content_type && $content_type == $ct_name[1])) {
        $templates[$template_name] = $template;
        $templates[$template_name]['content_type'] = $ct_name[1];
      }
      elseif ($content_type != $ct_name[1]) {
        unset($templates[$template_name]);
      }

      // Filter by widget type.
      if ($widget_type && $widget_type != $template['widget']) {
        unset($templates[$template_name]);
      }
    }
    // Template exists in DB but is not declared - remove it.
    else {
      db_delete('ding_nodelist_templates')
        ->condition('filename', $template_name)
        ->execute();
    }
  }

  ksort($templates);

  return $templates;
}

/**
 * Save CT plugin form values.
 */
function _ding_nodelist_content_type_form_save(&$form_state, $rebuild = FALSE) {
  $form_state['conf']['list_type'] = $form_state['values']['list_type'];
  $form_state['conf']['dynamic_switch'] = ($form_state['conf']['list_type'] === 'custom-dynamic') ? $form_state['values']['dynamic_switch'] : 0;
  $form_state['conf']['nodes_switch'] = ($form_state['conf']['list_type'] === 'custom-dynamic') ? $form_state['values']['nodes_switch'] : 0;

  $form_state['conf']['autoscroll_delay'] = $form_state['values']['autoscroll_delay'];
  $form_state['conf']['columns'] = $form_state['values']['columns'];
  $form_state['conf']['content_filter_promoted'] = $form_state['values']['content_filter_promoted'];
  $form_state['conf']['content_filter_date'] = $form_state['values']['content_filter_date'];
  $form_state['conf']['content_type'] = $form_state['values']['content_type'];

  $limit = 0;
  if ($form_state['conf']['dynamic_switch'] || $form_state['conf']['list_type'] === 'all') {
    $limit = $form_state['values']['limit'];
  }

  $form_state['conf']['limit'] = $limit;
  $form_state['conf']['more_links'] = !empty($form_state['values']['more_links']) ? $form_state['values']['more_links'] : array();
  $form_state['conf']['override_title_text'] = $form_state['values']['override_title_text'];
  $form_state['conf']['selected_nodes'] = !empty($form_state['values']['selected_nodes']) && $form_state['conf']['nodes_switch'] ? $form_state['values']['selected_nodes'] : array();
  $form_state['conf']['sort_field'] = $form_state['values']['sort_field'];
  $form_state['conf']['sort_order'] = $form_state['values']['sort_order'];
  $form_state['conf']['taxonomy_filters'] = !empty($form_state['values']['taxonomy_filters']) && $form_state['conf']['dynamic_switch'] ? $form_state['values']['taxonomy_filters'] : array();
  $form_state['conf']['unique_id'] = 'pane-' . (microtime(TRUE) * 10000);
  $form_state['conf']['widget_type'] = $form_state['values']['widget_type'];

  // @todo
  // As for now the template config is still there, so here we fetch the very
  // first assigned template.
  $item_templates = _ding_nodelist_get_templates(FALSE, $form_state['values']['content_type'], $form_state['conf']['widget_type']);
  $template = is_array($item_templates) ? reset($item_templates) : NULL;
  $form_state['conf']['item_template'] = isset($template['filename']) ? $template['filename'] : '';

  // Not a final save yet.
  if ($rebuild) {
    $form_state['rebuild'] = TRUE;
  }
  // Finally, save cache settings to display cache.
  else {
    _ding_nodelist_simple_cache_save($form_state);
  }
}

/**
 * Saves simple cache settings.
 */
function _ding_nodelist_simple_cache_save(&$form_state) {
  // Save cache settings.
  $pane_cache = &$form_state['pane']->cache;
  $pane_cache['method'] = 'simple';
  $pane_cache['settings'] = array(
    // Defaults the setting for users w/o cache access to 30 minutes.
    'lifetime' => user_access('nodelist cache settings') && isset($form_state['values']['lifetime']) ? $form_state['values']['lifetime'] : variable_get('ding_nodelist_cache_default_time', NL_CACHE_LIFETIME),
    'granularity' => 'context',
  );

  // Invalidate old cache.
  // @todo: check if any changes were introduced.
  ctools_include('plugins');
  $simple_cache_plugin = ctools_plugin_get_info('panels', 'cache');
  ctools_plugin_load_includes($simple_cache_plugin);
  $cid = panels_simple_cache_get_id($pane_cache['settings'], $form_state['display'], array() /* args not used */, $form_state['contexts'], $form_state['pane']);
  cache_clear_all($cid, 'cache');
}

/**
 * Retreive all nodes based on dynamic list settings.
 * @return array of node IDs
 */
function _ding_nodelist_get_dynamic_list_nodes($conf) {
  $nodes = array();

  // Do not fetch anything if custom content already fetched for single item widget.
  if (!empty($conf['custom_content']) && $conf['widget_type'] == NL_WIDGET_SINGLE) {
    return array();
  }

  // Support for slave-master DB servers.
  $query = db_select('node', 'n', array('target' => 'slave'))->fields('n', array('nid'));

  if (!empty($conf['taxonomy_filters'])) {
    $ti_l = 'ti';
    $query->join('taxonomy_index', $ti_l, "n.nid = $ti_l.nid");
    $i = 1;
    foreach ($conf['taxonomy_filters'] as $filter) {
      $ti_r = 'ti' . $i++;
      $filter['filter_terms'] = is_array($filter['filter_terms']) ? $filter['filter_terms'] : array($filter['filter_terms']);
      // Use $i in argument placeholder as workaround.
      $ti_l = $query->join('taxonomy_index', $ti_r, "$ti_l.nid = $ti_r.nid AND $ti_r.tid IN (:tids$i)", array(":tids$i" => $filter['filter_terms']));
    }
  }

  // Filter by content type/node settings.
  $query->condition('n.type', $conf['content_type'])
    ->condition('n.status', NODE_PUBLISHED)
    ->distinct();
  if (!empty($conf['content_filter_promoted'])) {
    $query->condition('n.promote', NODE_PROMOTED);
  }

  // Filter by date field.
  // @todo: remove hardcode.
  if (!empty($conf['content_filter_date'])) {
    $query->join('field_data_field_event_date', 'fed', 'n.nid = fed.entity_id');
    // @todo: NOW() works for visitors from the same timezone.
    $query->where(
      'DATE_FORMAT(fed.field_event_date_value, :format) >= CURRENT_DATE()'
      . ' OR DATE_FORMAT(fed.field_event_date_value2, :format) >= CURRENT_DATE()', array(':format' => '%Y-%m-%d'));
  }

  if ($conf['sort_field']) {
    if ($conf['sort_field'] == 'event_date') {
      $query->join('field_data_field_event_date', 'fed', 'fed.entity_id = n.nid');
      $query->orderBy('fed.field_event_date_value', $conf['sort_order']);
    }
    else {
      $query->orderBy('n.' . $conf['sort_field'], $conf['sort_order']);
    }
  }

  // Limit to 1 for single node widget.
  if ($conf['widget_type'] == NL_WIDGET_SINGLE) {
    $query->range(0, 1);
  }
  elseif ($conf['limit']) {
    $query->range(0, $conf['limit']);
  }

  $nodes = $query->execute()->fetchCol();

  return $nodes;
}

/**
 * Retreive all nodes based on custom list settings.
 * @return array of node IDs
 */
function _ding_nodelist_get_custom_list_nodes(&$conf) {
  $nodes = array();

  if (isset($conf['selected_nodes']) && count($conf['selected_nodes'])) {
    foreach ($conf['selected_nodes'] as $key => $node) {
      $nodes[$node['weight']] = $node['nid'];
    }
    // Sort the nodes according to their weight.
    ksort($nodes);
    $conf['custom_content'] = TRUE;
    if ($conf['widget_type'] == NL_WIDGET_SINGLE) {
      return array_slice($nodes, 0, 1);
    }
  }

  return $nodes;
}

/**
 * Sort callback to compare nodes by event date field.
 *
 * @param stdClass $a
 *   Node a.
 * @param stdClass $b
 *   Node b.
 *
 * @return int
 *   Values -1 (smaller), 0 (equal), 1 (bigger).
 */
function _ding_nodelist_sort_nodes_by_event_date($a, $b) {
  $field = field_get_items('node', $a, 'field_event_date');
  $time = new DateTime($field[0]['value'], new DateTimeZone('UTC'));
  $time1 = $time->getTimestamp();

  $field = field_get_items('node', $b, 'field_event_date');
  $time = new DateTime($field[0]['value'], new DateTimeZone('UTC'));
  $time2 = $time->getTimestamp();

  if ($time1 < $time2) {
    return -1;
  }
  if ($time1 == $time2) {
    return 0;
  }
  return 1;
}

/**
 * Sort callback to compare nodes by created date.
 *
 * @param stdClass $a
 *   Node a.
 * @param stdClass $b
 *   Node b.
 *
 * @return int
 *   Values -1 (smaller), 0 (equal), 1 (bigger).
 */
function _ding_nodelist_sort_nodes_by_created($a, $b) {
  if ($a->created < $b->created) {
    return -1;
  }
  if ($a->created == $b->created) {
    return 0;
  }
  return 1;
}

/**
 * Sort callback to compare nodes by title.
 *
 * @param stdClass $a
 *   Node a.
 * @param stdClass $b
 *   Node b.
 *
 * @return int
 *   Values -1 (smaller), 0 (equal), 1 (bigger).
 */
function _ding_nodelist_sort_nodes_by_title($a, $b) {
  return strnatcasecmp($a->title, $b->title);
}

/**
 * Sort callback to compare nodes by sticky flag.
 *
 * @param stdClass $a
 *   Node a.
 * @param stdClass $b
 *   Node b.
 *
 * @return int
 *   Values -1 (smaller), 0 (equal), 1 (bigger).
 */
function _ding_nodelist_sort_nodes_by_sticky($a, $b) {
  // "a" is sticky, "b" is not.
  if ($a->sticky && !$b->sticky) {
    return -1;
  }
  // "b" is sticky, "a" is not.
  if (!$a->sticky && $b->sticky) {
    return 1;
  }

  // Both have same flag.
  return 0;
}

/**
 * Sorts the nodes according to the settings.
 *
 * @param array $nodes
 *   List of loaded node objects.
 * @param array $conf
 *   Nodelist configuration.
 *
 * @return array
 *   Sorted nodes.
 */
function _ding_nodelist_sort_nodes($nodes, $conf) {
  if ($conf['sort_field']) {
    $callback = '_ding_nodelist_sort_nodes_by_' . $conf['sort_field'];

    usort($nodes, $callback);
    if ($conf['sort_order'] == 'desc') {
      $nodes = array_reverse($nodes);
    }
    return $nodes;
  }
  else {
    return $nodes;
  }
}

/**
 * Customized function for taxononmy autocomplete element validation
 * (copied from core's taxonomy_autocomplete_validate).
 * @see taxonomy_autocomplete_validate()
 */
function _ding_nodelist_taxonomy_autocomplete_validate($element, &$form_state) {
  // Autocomplete widgets do not send their tids in the form, so we must detect
  // them here and process them independently.
  $value = array();
  if ($tags = $element['#value']) {
    // Collect candidate vocabularies.
    $vocabularies = array();
    $vocabulary = taxonomy_vocabulary_machine_name_load($element['#vocabulary_name']);
    $vocabularies[$vocabulary->vid] = $vocabulary;

    // Translate term names into actual terms.
    $typed_terms = drupal_explode_tags($tags);
    foreach ($typed_terms as $typed_term) {
      // See if the term exists in the chosen vocabulary and return the tid;
      // otherwise, create a new 'autocreate' term for insert/update.
      if ($possibilities = taxonomy_term_load_multiple(array(), array('name' => trim($typed_term), 'vid' => array_keys($vocabularies)))) {
        $term = array_pop($possibilities);
      }
      else {
        form_error($element, t('Invalid term(s).'));
        return;
      }
      $value[] = (int) $term->tid;
    }
  }

  form_set_value($element, $value, $form_state);
}

/**
 * Scans templates module sub-directory for template files and returns them.
 */
function _ding_nodelist_get_core_templates() {
  // Get core templates from files.
  $templates = array();
  $path = drupal_get_path('module', 'ding_nodelist') . '/templates';
  $template_files = drupal_system_listing('/^ding_nodelist\..+\.tpl\.php$/', $path, 'filename', 0);
  foreach ($template_files as $template_name => $file) {
    $template_name = str_replace('.tpl.php', '', $template_name);
    $templates[$template_name] = array(
      'filename' => $template_name,
    );
  }

  return $templates;
}

/**
 * Checks if the link provided is either a valid external link
 * or a valid local Drupal path (to views, pages, nodes, terms etc).
 *
 * @param $link
 *   The link to validate.
 * @return boolean
 *   TRUE if the link is valid, FALSE otherwise.
 */
function _ding_nodelist_is_valid_link($link) {
  $langs = array_keys(language_list());

  // Trim / and possible language prefix.
  $link = ltrim($link, '/');
  $lang = arg(0, $link);
  if (in_array($lang, $langs)) {
    $link = substr($link, 3);
  }

  // Check if local path exists or external link is well formed.
  if (!valid_url($link, TRUE) && !drupal_valid_path($link, TRUE) && $link != '<front>') {
    $path = drupal_lookup_path('source', $link);
    if (!($path || drupal_valid_path($path))) {
      return FALSE;
    }
  }

  return TRUE;
}

/**
 * Returns an array of widget types that can be used as #options
 * in a select input otionally for a specific content type.
 *
 * @param $content_type
 *   Content type.
 * @return list of widget options
 */
function _ding_nodelist_get_widget_types($content_type = NULL) {
  $widgets = array(
    NL_WIDGET_SINGLE => t('Single item'),
    NL_WIDGET_CAROUSEL => t('Carousel'),
    NL_WIDGET_HOR_ACCORDION => t('Horizontal accordion'),
    NL_WIDGET_VER_ACCORDION => t('Vertical accordion'),
    NL_WIDGET_SLIDER => t('Slider'),
    NL_WIDGET_TAXONOMY_LIKE => t('Taxonomy like'),
  );

  // Fetch only widgets that have templates configured.
  if ($content_type) {
    $supported_widgets = db_select('ding_nodelist_templates', 't')
      ->fields('t', array('widget'))
      ->condition('t.filename', "%.$content_type.%", 'LIKE')
      ->condition('t.status', NL_TPL_ACTIVE)
      ->execute()
      ->fetchAllKeyed(0, 0);
    $supported_widgets = array_intersect_key($widgets, $supported_widgets);
    return $supported_widgets;
  }

  return $widgets;
}

/**
 * Translates constant definitions to numbers.
 */
function _ding_nodelist_get_column_map() {
  return array(
    NL_COL_FULL => 1,
    NL_COL_HALF => 1 / 2,
    NL_COL_THIRD => 1 / 3,
    NL_COL_QRT => 1 / 4,
  );
}

/**
 * Method used for receiving event date.
 * Used in ding_event nodelist templates.
 *
 * @param object $event_node
 * @return string
 */
function _ding_nodelist_get_event_date($event_node) {
  $event_date = field_get_items('node', $event_node, 'field_event_date');

  $start = new DateTime($event_date[0]['value'], new DateTimeZone('UTC'));
  $start = $start->getTimestamp();

  $end = new DateTime($event_date[0]['value2'], new DateTimeZone('UTC'));
  $end = $end->getTimestamp();

  $result = $start;
  $now = time();
  if ($start <= $now && $now <= $end) {
    $result = $now;
  }

  return $result;
}

/**
 * Method used for receiving image details like path, alt and title.
 * Used in ding_nodelist templates.
 *
 * @param object $node
 *  The node object.
 * @return array
 *   Image details ready to be used as options to theme_image_style
 *   or empty array if no image/attributes were found.
 */
function _ding_nodelist_get_dams_image_info($node, $image_field) {
  $image = field_get_items('node', $node, $image_field);
  if ($image) {
    $image = reset($image);
    $path = $image['uri'];
    $title = !empty($image['field_file_image_title_text']) ? $image['field_file_image_title_text']['und'][0]['safe_value'] : '';
    $alt = !empty($image['field_file_image_alt_text']) ? $image['field_file_image_alt_text']['und'][0]['safe_value'] : $title;
    return array(
      'path' => $path,
      'title' => $title,
      'alt' => $alt
    );
  }
  return array();
}

/**
 * Strips all HTML tags in body.
 */
function _ding_nodelist_striptags($nodes) {
  foreach ($nodes as $n => $node) {
    foreach ($node->field_ding_body as $lng => $body) {
      $nodes[$n]->field_ding_body[$lng][0]['safe_value'] = preg_replace('/<[^>]+>/i', '', $body[0]['safe_value']);
    }
  }
  return $nodes;
}

/**
 * Implements hook_date_format_types().
 */
function ding_nodelist_date_format_types() {
  return array(
    'nodelist_ding_page_taxonomy'  => t('Nodelist Ding page Taxonomy'),
    'nodelist_event_slider'  => t('Nodelist Event Slider'),
    'nodelist_event_taxonomy'  => t('Nodelist Event Taxonomy'),
    'nodelist_news_slider'  => t('Nodelist News Slider'),
    'nodelist_news_taxonomy'  => t('Nodelist News Taxonomy'),
    'nodelist_news_text'  => t('Nodelist News Text'),
  );
}

/**
 * Implements hook_date_formats().
 */
function ding_nodelist_date_formats() {
  $formats = array();
  $formats[] = array(
    'type'    => 'nodelist_ding_page_taxonomy',
    'format'  => 'Y-m-d',
  );
  $formats[] = array(
    'type'    => 'nodelist_event_slider',
    'format'  => 'd/m/Y',
  );
  $formats[] = array(
    'type'    => 'nodelist_event_taxonomy',
    'format'  => 'Y-m-d',
  );
  $formats[] = array(
    'type'    => 'nodelist_news_slider',
    'format'  => 'd/m/Y',
  );
  $formats[] = array(
    'type'    => 'nodelist_news_taxonomy',
    'format'  => 'd/m/Y',
  );
  $formats[] = array(
    'type'    => 'nodelist_news_text',
    'format'  => 'd/m/Y',
  );

  // Set default values.
  foreach ($formats as $format) {
    if (!variable_get('date_format_' . $format['type'])) {
      variable_set('date_format_' . $format['type'], $format['format']);
    }
  }

  return $formats;
}

/**
 * Helper function that returns ding_news date by predefined format.
 */
function _ding_nodelist_get_ding_news_date($node, $format = 'nodelist_news_taxonomy') {
  $date = !empty($node->publish_on) ? $node->publish_on : $date = $node->created;
  return format_date($date, $format);
}

include_once('ding_nodelist.features.inc');