import lombok.Getter;
import lombok.Setter;
import java.util.Date;
import java.util.concurrent.Delayed;
import java.util.concurrent.TimeUnit;

@Setter
@Getter
public class ItemDelayed<T> implements Delayed {

    /**默認(rèn)延遲30分鐘*/
    private final static long DELAY = 30 * 60 * 1000L;
    /**數(shù)據(jù)id*/
    private Long dataId;
    /**開始時間*/
    private long startTime;
    /**到期時間*/
    private long expire;
    /**創(chuàng)建時間*/
    private Date now;
    /**泛型data*/
    private T data;
    
    public ItemDelayed(Long dataId, long startTime, long secondsDelay) {
        super();
        this.dataId = dataId;
        this.startTime = startTime;
        this.expire = startTime + (secondsDelay * 1000);
        this.now = new Date();
    }

    public ItemDelayed(Long dataId, long startTime) {
        super();
        this.dataId = dataId;
        this.startTime = startTime;
        this.expire = startTime + DELAY;
        this.now = new Date();
    }

    @Override
    public int compareTo(Delayed o) {
        return (int) (this.getDelay(TimeUnit.MILLISECONDS) - o.getDelay(TimeUnit.MILLISECONDS));
    }

    @Override
    public long getDelay(TimeUnit unit) {
        return unit.convert(this.expire - System.currentTimeMillis(), TimeUnit.MILLISECONDS);
    }
}

public interface DelayOrder<T> {

    /**
     * 添加延遲對象到延時隊(duì)列
     *
     * @param itemDelayed 延遲對象
     * @return boolean
     */
    boolean addToOrderDelayQueue(ItemDelayed<T> itemDelayed);

    /**
     * 根據(jù)對象添加到指定延時隊(duì)列
     *
     * @param data 數(shù)據(jù)對象
     * @return boolean
     */
    boolean addToDelayQueue(T data);

    /**
     * 移除指定的延遲對象從延時隊(duì)列中
     *
     * @param data
     */
    void removeToOrderDelayQueue(T data);
}

@Slf4j
@Lazy(false)
@Component
public class DelayOwnOrderImpl implements DelayOrder<Order> {

    @Autowired
    private OrderService orderService;

    @Autowired
    private ExecutorService delayOrderExecutor;

    private final static DelayQueue<ItemDelayed<Order>> DELAY_QUEUE = new DelayQueue<>();

    /**
     * 初始化時加載數(shù)據(jù)庫中需處理超時的訂單
     * 系統(tǒng)啟動:掃描數(shù)據(jù)庫中未支付(要在更新時:加上已支付就不用更新了),未過期的的訂單
     */
    @PostConstruct
    public void init() {
        log.info("系統(tǒng)啟動:掃描數(shù)據(jù)庫中未支付,未過期的的訂單");
        List<Order> orderList = orderService.selectFutureOverTimeOrder();
        for (Order order : orderList) {
            ItemDelayed<Order> orderDelayed = new ItemDelayed<>(order.getId(), order.getCreateDate().getTime());
            this.addToOrderDelayQueue(orderDelayed);
        }
        log.info("系統(tǒng)啟動:掃描數(shù)據(jù)庫中未支付的訂單,總共掃描了" + orderList.size() + "個訂單,推入檢查隊(duì)列,準(zhǔn)備到期檢查...");

        /*啟動一個線程，去取延遲訂單*/
        delayOrderExecutor.execute(() -> {
            log.info("啟動處理的訂單線程:" + Thread.currentThread().getName());
            ItemDelayed<Order> orderDelayed;
            while (true) {
                try {
                    orderDelayed = DELAY_QUEUE.take();
                    //處理超時訂單
                    orderService.updateCloseOverTimeOrder(orderDelayed.getDataId());
                } catch (Exception e) {
                    log.error("執(zhí)行自營超時訂單的_延遲隊(duì)列_異常:" + e);
                }
            }
        });
    }

    /**
     * 加入延遲消息隊(duì)列
     **/
    @Override
    public boolean addToOrderDelayQueue(ItemDelayed<Order> orderDelayed) {
        return DELAY_QUEUE.add(orderDelayed);
    }

    /**
     * 加入延遲消息隊(duì)列
     **/
    @Override
    public boolean addToDelayQueue(Order order) {
        ItemDelayed<Order> orderDelayed = new ItemDelayed<>(order.getId(), order.getCreateDate().getTime());
        return DELAY_QUEUE.add(orderDelayed);
    }

    /**
     * 從延遲隊(duì)列中移除 主動取消就主動從隊(duì)列中取出
     **/
    @Override
    public void removeToOrderDelayQueue(Order order) {
        if (order == null) {
            return;
        }
        for (Iterator<ItemDelayed<Order>> iterator = DELAY_QUEUE.iterator(); iterator.hasNext(); ) {
            ItemDelayed<Order> queue = iterator.next();
            if (queue.getDataId().equals(order.getId())) {
                DELAY_QUEUE.remove(queue);
            }
        }
    }
}