package com.exp.components.retry.impl;

import com.exp.components.entity.Message;
import com.exp.components.retry.Retrier;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.List;
import java.util.UUID;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.Function;
import java.util.stream.Collectors;

public class SenderRetrier implements Retrier {
    private static final Logger LOG = LoggerFactory.getLogger(SenderRetrier.class);

    private ConcurrentHashMap<UUID, Message> pendingMessages;
    private ConcurrentHashMap<UUID, Integer> retryMap;
    private int maxRetries;

    public SenderRetrier(int maxRetries) {
        this.maxRetries = maxRetries;
        this.pendingMessages = new ConcurrentHashMap<>();
        this.retryMap = new ConcurrentHashMap<>();
    }

    @Override
    public Message retry(UUID msgId) {
        Message message = pendingMessages.get(msgId);
        if (message == null) {
            return null;
        }

        Integer retryNum = retryMap.get(msgId);
        if (retryNum >= maxRetries) {
            LOG.info("Reached max retries: {}, assume message: {} is poison", retryNum, msgId);
            deletePendingMessage(msgId);
            return null;
        }
        LOG.info("Try resend message: {}, current retries: {}", msgId, retryNum);
        retryMap.replace(msgId, ++retryNum);
        return message;
    }

    @Override
    public void deletePendingMessage(UUID msgId) {
        pendingMessages.remove(msgId);
        retryMap.remove(msgId);
    }

    @Override
    public void deletePendingMessages(List<UUID> uuidList) {
        uuidList.forEach(id -> {
            pendingMessages.remove(id);
            retryMap.remove(id);
        });
    }

    @Override
    public void addPendingMessages(List<Message> messages) {
        pendingMessages.putAll(messages.stream().collect(Collectors.toMap(Message::getId, Function.identity())));
        retryMap.putAll(messages.stream().collect(Collectors.toMap(Message::getId, m -> 1)));
    }

    @Override
    public void addPendingMessage(Message message) {
        pendingMessages.put(message.getId(), message);
        retryMap.put(message.getId(), 1);
    }
}