package ru.ensemplix.storage;

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;


public class CachedStorage<V> extends LinkedHashMap<String, V> {

    private final Queue<V> add = new ConcurrentLinkedQueue<>();
    private final Queue<V> remove = new ConcurrentLinkedQueue<>();

    public CachedStorage(Storage<V> storage, String key) {
        super.putAll(storage.get(key));

        Executors.newSingleThreadScheduledExecutor().schedule(new Runnable() {
            @Override
            public void run() {
                try {
                    System.out.println("Saving");

                    while(!remove.isEmpty()) {
                        storage.remove(remove.poll());
                    }

                    while(!add.isEmpty()) {
                        storage.add(add.poll());
                    }
                } catch(Exception e) {
                    e.printStackTrace();
                }
            }
        }, 5, TimeUnit.SECONDS);
    }

    @Override
    public V put(String key, V value) {
        add.add(value);
        return super.put(key, value);
    }

    @Override
    public void putAll(Map<? extends String, ? extends V> map) {
        add.addAll(map.values());
        super.putAll(map);
    }

    @Override
    public V remove(Object key) {
        V value = super.remove(key);

        if(value != null) {
            remove.remove(value);
        }

        return value;
    }


}