package teamspeak

// diffSlices 比较两个 OnlineClient 类型切片，以 DatabaseID 为基准，返回新增和删除的 []OnlineClient
func diffSlices(old, new []Client) (added, removed []Client) {
	oldMap := make(map[int]Client)
	nowMap := make(map[int]Client)

	for _, item := range old { oldMap[item.DatabaseID] = item }
	for _, item := range new { nowMap[item.DatabaseID] = item }

	for id, item := range nowMap {
		if _, exists := oldMap[id]; !exists {
			added = append(added, item)
		}
	}

	for id, item := range oldMap {
		if _, exists := nowMap[id]; !exists {
			removed = append(removed, item)
		}
	}

	return added, removed
}