package com.matrix.system.common.init;

import com.google.common.util.concurrent.ThreadFactoryBuilder;
import com.matrix.core.tools.LogUtil;
import com.matrix.core.tools.StringUtils;
import lombok.Data;

import java.util.Iterator;
import java.util.Map;
import java.util.Objects;
import java.util.Set;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicLong;
import java.util.stream.Collectors;

public class LocalCache {

    /*
     * 清理线程运行状态 0 未启动，1 已启动
     */
    private static int CLEAR_THREAD_STATUS = 0;

    private static ConcurrentMap<String, Value> localCache = new ConcurrentHashMap(60);

    /**
     * 根据key匹配多个缓存值
     *
     * @param key
     * @param <T>
     * @return
     */
    public static <T> Map<String, T> getValues(String key) {
        return localCache.entrySet().stream()
                .filter(item -> StringUtils.isMatch(key, item.getKey()))
                .map(Map.Entry::getValue)
                .filter(item -> Objects.nonNull(item.value))
                .collect(Collectors.toMap(Value::getKey, item -> (T) item.value));
    }

    /**
     * 获取本地缓存
     *
     * @param key
     * @param <T>
     * @return
     */
    public static <T> T get(String key) {
        Value value = localCache.get(key);
        if (Objects.nonNull(value)) {
            return (T) value.value;
        }
        return null;
    }

    /**
     * 删除缓存
     *
     * @param key
     * @param <T>
     * @return
     */
    public static <T> T remove(String key) {
        Value value = localCache.remove(key);
        if (Objects.nonNull(value)) {
            return (T) value.value;
        }
        return null;
    }

    /**
     * 批量删除缓存
     *
     * @param key
     * @return
     */
    public static int batchRemove(String key) {
        int count = 0;
        Set<Map.Entry<String, Value>> entries = localCache.entrySet();
        Iterator<Map.Entry<String, Value>> iterator = entries.iterator();
        while (iterator.hasNext()) {
            Map.Entry<String, Value> next = iterator.next();
            if (StringUtils.isMatch(key, next.getKey())) {
                remove(next.getKey());
                count++;
            }
        }
        return count;
    }

    /**
     * 保存一个本地缓存
     *
     * @param key
     * @param value
     */
    public static void save(String key, Object value) {
        if (null != localCache.put(key, buildValue(key, value))) {
            LogUtil.debug("覆盖原有缓存{}", key);
        }
    }

    /**
     * 设置含过期时间的缓存
     *
     * @param key
     * @param value
     * @param timeOut 毫秒
     */
    public static void save(String key, Object value, long timeOut) {
        if (null != localCache.put(key, buildValue(key, value, timeOut))) {
            LogUtil.debug("覆盖原有缓存{}", key);
        }
        startClearThread();
    }

    /**
     * 重置缓存失效时间
     * @param key
     */
    public static void resetExpire(String key) {
        Objects.requireNonNull(key);
        Value value = localCache.get(key);
        if(Objects.nonNull(value)){
            value.getCreateTime().set(System.currentTimeMillis());
        }
    }

    /**
     * 清理过期对象
     */
    private synchronized static void startClearThread() {
        if (CLEAR_THREAD_STATUS == 0) {
            ThreadFactory namedThreadFactory = new ThreadFactoryBuilder()
                    .setNameFormat("demo-pool-%d").build();
            ExecutorService singleThreadPool = new ThreadPoolExecutor(1, 1,
                    0L, TimeUnit.MILLISECONDS,
                    new LinkedBlockingQueue<Runnable>(1), namedThreadFactory, new ThreadPoolExecutor.AbortPolicy());
            singleThreadPool.execute(() -> {
                CLEAR_THREAD_STATUS = 1;
                while (true) {
                    try {
                        Set<Map.Entry<String, Value>> entries = localCache.entrySet();
                        Iterator<Map.Entry<String, Value>> iterator = entries.iterator();
                        while (iterator.hasNext()) {
                            Map.Entry<String, Value> next = iterator.next();

                            if (next.getValue().timeOut == 0) {
                                continue;
                            }

                            boolean isTimeOut = (System.currentTimeMillis() - next.getValue().getCreateTime().longValue()) > next.getValue().timeOut;
                            if (isTimeOut) {
                                Value removed = localCache.remove(next.getKey());
                                LogUtil.debug("清除过期对象:{}", removed.value);
                            }
                        }
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        LogUtil.error("清理缓存线程异常停止", e);
                        CLEAR_THREAD_STATUS = 0;
                    }
                }
            });


        }
    }


    private static Value buildValue(String key, Object value) {
        return buildValue(key, value, 0);
    }


    private static Value buildValue(String key, Object value, long timeOut) {
        Value instances = new Value();
        instances.createTime = new AtomicLong(System.currentTimeMillis());
        instances.key = key;
        instances.value = value;
        instances.timeOut = timeOut;
        return instances;
    }




    /**
     * 缓存对象
     */
    @Data
    static class Value {

        /**
         * 过期时间,0 表示不过期,单位毫秒
         */
        private long timeOut = 0;
        /**
         * 缓存key
         */
        private String key;
        /**
         * 缓存值
         */
        private Object value;

        /**
         * 缓存创建时间
         */
        private AtomicLong createTime;


    }


}