package com.jsowell.common.util;

import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelId;
import io.netty.channel.group.ChannelGroup;
import io.netty.channel.group.DefaultChannelGroup;
import io.netty.util.concurrent.GlobalEventExecutor;
import lombok.extern.slf4j.Slf4j;

import java.net.InetSocketAddress;
import java.util.concurrent.ConcurrentHashMap;

/**
 * 管理一个全局map，保存连接进服务端的通道数量
 */
@Slf4j
public class ChannelManagerUtil {

    // 使用 ConcurrentHashMap 来保证线程安全
    private static final ConcurrentHashMap<ChannelId, ChannelHandlerContext> CHANNEL_MAP = new ConcurrentHashMap<>();

    private static final ChannelGroup group = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);

    public static void add(Channel channel) {
        group.add(channel);
    }

    public static Channel find(ChannelId channelId) {
        return group.find(channelId);
    }

    public static void remove(Channel channel) {
        group.remove(channel);
    }

    public static void remove(ChannelId channelId) {
        group.remove(channelId);
    }

    /**
     * 添加通道到 map 中
     *
     * @param channelId 通道 ID
     * @param ctx   连接的 Channel 对象
     */
    public static void addChannel(ChannelId channelId, ChannelHandlerContext ctx) {
        if (CHANNEL_MAP.containsKey(channelId)) {
            log.info("客户端【{}】是连接状态，连接通道数量: {}", channelId, CHANNEL_MAP.size());
        } else {
            CHANNEL_MAP.put(channelId, ctx);
            InetSocketAddress socket = (InetSocketAddress) ctx.channel().remoteAddress();
            String clientIp = socket.getAddress().getHostAddress();
            int clientPort = socket.getPort();
            log.info("客户端【{}】, 连接netty服务器【IP:{}, PORT:{}】, 连接通道数量: {}", channelId, clientIp, clientPort, CHANNEL_MAP.size());
        }
    }

    /**
     * 移除指定的通道
     *
     * @param channelId 通道 ID
     */
    public static void removeChannel(ChannelId channelId) {
        if (!CHANNEL_MAP.containsKey(channelId)) {
            return;
        }
        CHANNEL_MAP.remove(channelId);
    }

    /**
     * 获取当前连接的通道数量
     *
     * @return 通道数量
     */
    public static int getChannelCount() {
        return CHANNEL_MAP.size();
    }

    /**
     * 根据通道 ID 获取 Channel 对象
     *
     * @param channelId 通道 ID
     * @return Channel 对象或 null 如果不存在
     */
    public static ChannelHandlerContext getChannel(ChannelId channelId) {
        return CHANNEL_MAP.get(channelId);
    }
}