// Lookup pre-existing records
$preexisting = civicrm_api3('entity_tag', 'get', $baseParams);
$preexisting = array_column($preexisting['values'], 'tag_id');
- $toAdd = isset($params['tag_id']) ? $params['tag_id'] : array_column($params['values'], 'tag_id');
+ $toAdd = $params['tag_id'] ?? array_column($params['values'], 'tag_id');
$toRemove = array_diff($preexisting, $toAdd);
$result = [];