package com.ard.work.component.netty;

import com.ard.work.component.netty.command.BaseCmd;
import com.ard.work.component.netty.command.register.HeartbeatCmd;
import com.ard.work.component.netty.handler.ClientHandler;
import com.ard.work.component.netty.handler.MessageProtocolDecoder;
import com.ard.work.component.netty.handler.MessageProtocolEncoder;
import com.ard.work.domain.cache.TyTcpServerCache;
import com.ard.work.domain.entity.ArdServerInfo;
import com.ard.work.service.IArdServerInfoService;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.timeout.IdleStateHandler;
import io.netty.util.AttributeKey;
import lombok.extern.slf4j.Slf4j;
import org.springframework.scheduling.annotation.Scheduled;
import org.springframework.stereotype.Component;
import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.net.InetSocketAddress;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;

@Component
@Slf4j
public class TyTcpClientManager {
    /**
     * 以 serverId 作为唯一 key
     */
    public static final Map<String, TcpClientSession> channels = new ConcurrentHashMap<>();

    private final EventLoopGroup eventLoopGroup = new NioEventLoopGroup();

    @Resource
    private IArdServerInfoService ardServerService; // ← 从数据库读取边缘服务器配置

    @Resource
    private ClientHandler clientHandler;

    /**
     * 初始化 Bootstrap
     */
    private Bootstrap getBootstrap() {
        Bootstrap bootstrap = new Bootstrap();
        bootstrap.group(eventLoopGroup)
                .channel(NioSocketChannel.class)
                .option(ChannelOption.TCP_NODELAY, true)
                .option(ChannelOption.SO_KEEPALIVE, true)
                .handler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    protected void initChannel(SocketChannel socketChannel) {
                        ChannelPipeline pipeline = socketChannel.pipeline();
                        pipeline.addLast("heart", new IdleStateHandler(0, 3, 0, TimeUnit.SECONDS));
                        pipeline.addLast("encoder", new MessageProtocolEncoder());
                        pipeline.addLast("decoder", new MessageProtocolDecoder());
                        pipeline.addLast("handler", clientHandler);
                    }
                });
        return bootstrap;
    }

    /**
     * 新增或重连服务器
     */
    public void connectServer(ArdServerInfo serverInfo) {
        String serverId = serverInfo.getId();
        String host = serverInfo.getHost();
        Integer port = serverInfo.getTcpPort();

        // 如果已有旧连接，先断开
        disconnectServer(serverId);

        Bootstrap bootstrap = getBootstrap();
        ChannelFuture future = bootstrap.connect(host, port).addListener((ChannelFuture f) -> {
            if (f.isSuccess()) {
                log.info("✅ 服务器 [{}] 连接成功", serverId);
                Channel channel = f.channel();
                channel.attr(AttributeKey.valueOf("serverId")).set(serverId);
                TyTcpServerCache.putTcpServerCache(serverId, true);
            } else {
                log.warn("❌ 服务器 [{}] 连接失败", serverId);
                TyTcpServerCache.putTcpServerCache(serverId, false);
            }
        });

        TcpClientSession session = TcpClientSession.builder()
                .ClientId("TY_" + serverId)
                .channelFuture(future)
                .isReConnect(true)
                .serverId(serverId)
                .host(host)
                .port(port)
                .build();

        channels.put(serverId, session);
    }

    /**
     * 断开服务器连接
     */
    public void disconnectServer(String serverId) {
        TcpClientSession session = channels.remove(serverId);
        if (session != null && session.getChannelFuture() != null) {
            session.getChannelFuture().channel().close();
            log.info("断开服务器 [{}] 连接", serverId);
        }
        TyTcpServerCache.removeTcpServerCache(serverId);
    }

    /**
     * 向指定边缘服务器发送消息
     */
    public void sendMessage(Long serverId, BaseCmd msg) {
        try {
            TcpClientSession session = channels.get(serverId);
            if (session == null) {
                log.error("未找到六合服务器 [{}] 的连接", serverId);
                return;
            }

            ChannelFuture future = session.getChannelFuture();
            if (future == null || !future.channel().isActive()) {
                log.warn("六合服务器 [{}] 连接未激活，无法发送消息", serverId);
                return;
            }

            InetSocketAddress remote = (InetSocketAddress) future.channel().remoteAddress();
            future.channel().writeAndFlush(msg);
            log.debug("→ 向六合服务器 [{}] ({}:{}) 发送消息，命令码：0x{}",
                    serverId, remote.getHostString(), remote.getPort(),
                    String.format("%02X", msg.getCmdCode() & 0xFF));
        } catch (Exception e) {
            log.error("发送消息到六合服务器 [{}] 异常：{}", serverId, e.getMessage());
        }
    }

    /**
     * 启动时从数据库加载所有边缘服务器并建立 TCP 连接
     */
    @PostConstruct
    public void initConnectServers() {
        try {
            var serverList = ardServerService.selectArdServerInfoList(new ArdServerInfo()); // ← 从数据库查询所有服务器配置
            if (serverList == null || serverList.isEmpty()) {
                log.warn("未在数据库中找到边缘服务器配置，跳过连接初始化");
                return;
            }

            for (ArdServerInfo serverInfo : serverList) {
                connectServer(serverInfo);
            }

            log.info("共初始化 {} 个边缘服务器连接", serverList.size());
        } catch (Exception e) {
            log.error("创建边缘服务器连接异常：{}", e.getMessage(), e);
        }
    }

    @Scheduled(fixedDelay = 10000) // 每 10 秒检查一次
    public void reconnectFailedServers() {
        TyTcpServerCache.getTcpServerCacheMap().forEach((key, state) -> {
            if (Boolean.FALSE.equals(state)) { // 连接失败的服务器
                ArdServerInfo serverInfo = ardServerService.selectArdServerInfoById(key);
                if (serverInfo != null) {
                    connectServer(serverInfo);
                }
            }
        });
    }

    /**
     * 定时向所有已连接的六合服务器发送心跳
     */
    @Scheduled(fixedRate = 5000) // 每5秒执行一次
    public void sendHeartBeat() {
        long timestamp = System.currentTimeMillis();
        channels.values().stream()
                .filter(session -> {
                    ChannelFuture future = session.getChannelFuture();
                    // 只保留活跃连接
                    return future != null && future.channel().isActive();
                })
                .forEach(session -> {
                    HeartbeatCmd heartbeat = new HeartbeatCmd(timestamp);
                    ChannelFuture future = session.getChannelFuture();
                    future.channel().writeAndFlush(heartbeat);
                    log.info("→ 向边缘服务器 [{}] ({}:{}) 发送心跳，时间戳={}",
                            session.getServerId(), session.getHost(), session.getPort(), timestamp);
                });
    }
}