package com.ard.tianyu.netty.handler;// MessageProtocolDecoder.java

import com.ard.tianyu.netty.command.BaseCommand;
import com.ard.tianyu.netty.command.HeartbeatReplyCommand;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.ByteToMessageDecoder;
import lombok.extern.slf4j.Slf4j;

import java.util.List;

@Slf4j
public class MessageProtocolDecoder extends ByteToMessageDecoder {
    @Override
    protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
        // 检查可读字节数是否足够
        if (in.readableBytes() < 4) {
            return; // 不足以读取头部
        }

        in.markReaderIndex(); // 标记当前读取位置
        short dataHead = in.readShort();
        if(dataHead != 0x6A77){
            return;
        }
        short dataLength = in.readShort();

        if (in.readableBytes() < dataLength) {
            in.resetReaderIndex(); // 如果不足，重置读取位置
            return;
        }
        byte cmdCode = in.readByte();
        BaseCommand command = null;

        // 根据 cmdCode 创建相应消息对象
        if (cmdCode == 0x01) { // 注册回复消息
            byte success = in.readByte(); // 读取是否成功
            log.warn("注册回复: {}", success == 0x01 ? "成功" : "失败");
        }
        if (cmdCode == 0x02) { // 注册回复消息
            long timestamp = in.readLong(); // 读取时间戳
            command = new HeartbeatReplyCommand(timestamp); // 创建心跳回复对象
            log.debug("心跳回复: 时间戳 {}", timestamp);
        }
        if (command != null) {
            out.add(command); // 添加解码的命令对象到输出列表
        } else {
            log.warn("无法识别的命令码: {}", cmdCode);//String.format("0x%02X", cmdCode & 0xFF)
        }
    }
}