package com.zhentao.information.handler;

import com.alibaba.fastjson.JSON;
import com.zhentao.groups.MongoDB.pojo.GroupMessage;
import com.zhentao.groups.MongoDB.pojo.Message;
import com.zhentao.information.entity.ChatMessage;
import com.zhentao.information.repository.ChatMessageRepository;
import com.zhentao.information.service.WebSocketService;
import com.zhentao.tool.TokenUtils;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.util.Date;

/**
 * WebSocket消息处理器
 * 处理WebSocket连接、消息接收和发送
 */
@Slf4j
@Component
@ChannelHandler.Sharable
public class WebSocketHandler extends SimpleChannelInboundHandler<TextWebSocketFrame> {

    @Resource
    private ChatMessageRepository chatMessageRepository;

    @Resource
    private WebSocketService webSocketService;

    /**
     * 处理接收到的WebSocket消息
     */
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, TextWebSocketFrame msg) throws Exception {
        String text = msg.text();
        log.info("收到消息：{}", text);
        try {
            Message message = JSON.parseObject(text, Message.class);
            log.info("接收到的消息：{}", message);
            
            // 如果是连接消息，处理token
            if ("connect".equals(message.getType())) {
                String userId = webSocketService.handleUserLogin(message.getContent(), ctx);
                log.info("用户 {} 登录成功", userId);
                if (userId != null) {
                    // 用户登录成功后，自动加入所有群聊
                    webSocketService.joinAllGroups(userId);
                    // 发送连接成功消息
                    Message response = new Message();
                    response.setType("connect_success");
                    response.setContent("连接成功");
                    ctx.channel().writeAndFlush(new TextWebSocketFrame(JSON.toJSONString(response)));
                }
                return;
            }

            // 如果是心跳消息
            if ("ping".equals(message.getType())) {
                Message pongMessage = new Message();
                pongMessage.setType("pong");
                ctx.channel().writeAndFlush(new TextWebSocketFrame(JSON.toJSONString(pongMessage)));
                return;
            }

            // 如果是群聊消息
            if (message.getGroupId() != null) {
                handleGroupMessage(message);
                return;
            }

            // 处理普通消息
            handleMessage(message);

        } catch (Exception e) {
            log.error("处理消息失败", e);
            // 发送错误消息给客户端
            Message errorMessage = new Message();
            errorMessage.setType("error");
            errorMessage.setContent("消息处理失败");
            ctx.channel().writeAndFlush(new TextWebSocketFrame(JSON.toJSONString(errorMessage)));
        }
    }

    /**
     * 处理群聊消息
     */
    private void handleGroupMessage(Message message) {
        // 设置群聊消息类型
        message.setType("group_chat");
        // 广播消息给群内所有成员
        boolean sent = webSocketService.handleGroupMessage(message);
        if (sent) {
            // 发送消息确认
            Message ackMessage = new Message();
            ackMessage.setType("message_ack");
            ackMessage.setContent("群消息已发送");
            webSocketService.sendMessageToUser(message.getFromUserId(), ackMessage);
        }
    }

    /**
     * 处理普通消息
     */
    private void handleMessage(Message message) {
        // 生成聊天ID
        String chatId = generateChatId(message.getFromUserId(), message.getToUserId());

        // 创建MongoDB消息对象
        ChatMessage chatMessage = new ChatMessage();
        chatMessage.setFromUserId(message.getFromUserId());
        chatMessage.setToUserId(message.getToUserId());
        chatMessage.setContent(message.getContent());
        chatMessage.setType(message.getType());
        chatMessage.setTimestamp(System.currentTimeMillis());
        chatMessage.setIsRead(false);
        chatMessage.setChatId(chatId);

        // 保存消息到MongoDB
        chatMessageRepository.save(chatMessage);

        // 发送消息给接收者
        boolean sent = webSocketService.sendMessageToUser(message.getToUserId(), message);
        if (sent) {
            log.info("消息已发送给用户: {}, 内容: {}", message.getToUserId(), message.getContent());
            // 发送消息确认给发送者
            Message ackMessage = new Message();
            ackMessage.setType("message_ack");
            ackMessage.setContent("消息已发送");
            webSocketService.sendMessageToUser(message.getFromUserId(), ackMessage);
        } else {
            log.info("用户 {} 不在线，消息已保存到MongoDB", message.getToUserId());
            // 发送消息未送达通知给发送者
            Message offlineMessage = new Message();
            offlineMessage.setType("message_offline");
            offlineMessage.setContent("对方不在线，消息已保存");
            webSocketService.sendMessageToUser(message.getFromUserId(), offlineMessage);
        }
    }

    /**
     * 当新的WebSocket连接建立时调用
     */
    @Override
    public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
        log.info("新的连接：{}", ctx.channel().id().asLongText());
    }

    /**
     * 当WebSocket连接断开时调用
     */
    @Override
    public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
        log.info("连接断开：{}", ctx.channel().id().asLongText());
        // 清理用户连接
        webSocketService.removeUserConnection(ctx);
    }

    /**
     * 处理异常情况
     */
    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        log.error("WebSocket异常", cause);
        ctx.close();
    }

    /**
     * 生成聊天ID
     */
    private String generateChatId(String userId1, String userId2) {
        // 确保两个用户之间的聊天ID唯一
        return userId1.compareTo(userId2) < 0 ?
            userId1 + "_" + userId2 :
            userId2 + "_" + userId1;
    }
}