package com.sipai.netty;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;

import java.io.IOException;
import java.nio.charset.Charset;
import java.util.Date;

public class NettyClientHandler extends ChannelInboundHandlerAdapter  {
    
    private NettyClient nettyClient;
    
    public NettyClientHandler(NettyClient nettyClient) {
        this.nettyClient = nettyClient;
    }
    
    /**
     * 通道信息读取处理
     * @param ctx
     * @param msg
     */
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) {
        ByteBuf m = (ByteBuf) msg; // 将消息转化成bytebuf
        try {
            System.out.println("客户端直接打印接收到的消息: " + m.toString(Charset.defaultCharset()));
            long currentTimeMillis = (m.readUnsignedInt() - 2208988800L) * 1000L;
            System.out.println(new Date(currentTimeMillis));
            /**
             * 给服务端回复消息
             */
            ctx.writeAndFlush("客户端收到! 消息为: " + m.toString(Charset.defaultCharset()));
        } catch (Exception e) {
            System.err.println("读取消息异常: " + e.getMessage());
        } finally {
            m.release();
        }
    }

    /**
     * 连接成功后，自动执行该方法
     * @param ctx
     * @throws Exception
     */
    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        /**
         * 往服务端发送消息
         * 消息格式必须是ByteBuf才行!!!!!
         * 如果是其他格式服务端是接收不到的!!!!
         */
        System.out.println("首次连接完成!");
        String helo = "你好呀!";
        ByteBuf byteBuf = Unpooled.wrappedBuffer(helo.getBytes());
        ctx.channel().writeAndFlush(byteBuf);
    }

    /**
     * 当连接断开时调用
     * @param ctx
     * @throws Exception
     */
    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        System.out.println("连接已断开，准备重连...");
        if (nettyClient != null) {
            nettyClient.reconnect();
        }
    }

    /**
     * 异常处理
     * @param ctx
     * @param cause
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
        // 处理远程主机强制关闭连接的异常
        if (cause instanceof IOException) {
            String message = cause.getMessage();
            if (message != null && (message.contains("远程主机强迫关闭了一个现有的连接") 
                    || message.contains("Connection reset")
                    || message.contains("远程主机强迫关闭") 
                    || message.contains("An existing connection was forcibly closed"))) {
                System.out.println("[" + java.time.LocalDateTime.now() + "] 远程主机已关闭连接，等待重连...");
                ctx.close();
                // 触发重连
                if (nettyClient != null) {
                    nettyClient.reconnect();
                }
                return;
            }
        }
        
        // 其他异常只打印简要信息，不打印完整堆栈
        System.err.println("[" + java.time.LocalDateTime.now() + "] 客户端异常：" + cause.getClass().getSimpleName() + " - " + cause.getMessage());
        ctx.close();
        
        // 触发重连
        if (nettyClient != null) {
            nettyClient.reconnect();
        }
    }
}