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<?php

/**
 * Implements hook_entity_presave().
 *
 * This hook autamatically sets an unpublish date for events so that they are no
 * longer indexed by search engines after event has occurred.
 */
function event_removal_entity_presave($entity, $type) {
  if($entity->type == 'event') {
    $start_date = date('U', strtotime($entity->field_date['und'][0]['value']));
    $end_date = date('U', strtotime($entity->field_date['und'][0]['value2']));

    if ($start_date > $end_date) {
      $entity->unpublish_on = strtotime('+1 day', $start_date);
    }
    else {
      $entity->unpublish_on = strtotime('+1 day', $end_date);
    }
  }
}