/**
 * @file SSE流路由处理器
 * @author Yk <yk_9001@icloud.com>
 * @createdAt 2025-07-01
 * @lastModifiedAt 2025-07-01
 * @description 处理SSE连接建立和维持
 */

const express = require('express');
const {v4: uuidV4} = require('uuid');
const {setupSSEHeaders} = require('../lib/sse');
const clients = require('../lib/clients');
const timestamp = require('../utils/timeFormatter');
const jwt = require('jsonwebtoken');
const config = require('../config'); // 引入配置

const router = express.Router();

router.get('/', (req, res) => {
    const { token } = req.query;
    // 增加解析token逻辑，
    if (!token) {
        res.status(401).json({message: 'Unauthorized: Token missing'});
        return;
    }
    // 解析Token 提取客户端ID
    let clientId
    try {
        // 解析Token并验证签名：
        // const decoded = jwt.verify(token, config.jwt.jwtSecret, {
        //     algorithms: ['HS256'],
        //     clockTolerance: 15, // 防止 Hyperf 生成后立即验证因 nbf 失败
        // });
        const decoded = jwt.decode(token);
        clientId = decoded.claims?.user_client_id || decoded.sub || uuidV4();
    } catch (err) {
        res.status(401).json({
            message: 'Unauthorized: Invalid token',
            error: err.message
        });
        return;
    }

    setupSSEHeaders(res);

    const initialData = {
        status: 'connected',
        clientId,
        time: timestamp.formatTime()
    };
    // 立即发送确认
    res.write(`data: ${JSON.stringify(initialData)}\n\n`);

    clients.add(clientId, res);

    req.on('close', () => {
        clients.remove(clientId);
    });
});

module.exports = router;