<?php

/**
 * @file
 * Field formatter class install file.
 */

/**
 * Implements hook_uninstall().
 */
function field_formatter_class_uninstall() {
  $field_info = field_info_fields();

  foreach ($field_info as $field) {
    foreach ($field['bundles'] as $entity_type => $bundles) {
      foreach ($bundles as $bundle) {

        // get the instance settings from the database
        $instance = db_select('field_config_instance', 'fci')
          ->fields('fci', array('data'))
          ->condition('field_name', $field['field_name'])
          ->condition('entity_type', $entity_type)
          ->condition('bundle', $bundle)
          ->execute()
          ->fetchField();

        $instance = unserialize($instance);

        // remove the display settings provided by this module
        foreach ($instance['display'] as &$display) {
          if (isset($display['settings']['field_formatter_class'])) {
            unset($display['settings']['field_formatter_class']);
          }
        }

        // re-serialize the instance, then save back to the database
        $instance = serialize($instance);
        db_update('field_config_instance')
          ->fields(array('data' => $instance))
          ->condition('field_name', $field['field_name'])
          ->condition('entity_type', $entity_type)
          ->condition('bundle', $bundle)
          ->execute();
      }
    }
  }
  field_cache_clear();

  // views displays
  if (db_table_exists('views_display')) {
    // Getting all view displays from database.
    $view_displays = db_select('views_display', 'vd')
      ->fields('vd')
      ->execute();

    // Iterate all view displays and modify them.
    foreach ($view_displays as $view_display) {
      $vid = $view_display->vid;
      $id = $view_display->id;

      $display_options = unserialize($view_display->display_options);

      // remove the display settings provided by this module
      if (isset($display_options['fields'])) {
        foreach ($display_options['fields'] as &$field) {
          $settings = &$field['settings'];
          if (isset($settings['field_formatter_class'])) {
            unset($settings['field_formatter_class']);
          }
        }
      }

      $display_options = serialize($display_options);

      // Finally we update the current view display.
      db_update('views_display')
        ->fields(array('display_options' => $display_options))
        ->condition('vid', $vid)
        ->condition('id', $id)
        ->execute();
    }
  }
}