const express = require('express');
const fs = require('fs').promises;
const path = require('path');
const cors = require('cors');
const bodyParser = require('body-parser');

const app = express();
const DATA_DIR = path.join(__dirname, 'data');
const DATA_FILE = path.join(DATA_DIR, 'urls.json');
const PORT = process.env.PORT || 3000;

// 中间件
app.use(cors());
app.use(bodyParser.json({ limit: '10mb' }));
app.use(express.static('public'));

// 确保数据目录存在
async function ensureDataDir() {
    try {
        await fs.mkdir(DATA_DIR, { recursive: true });
    } catch (error) {
        console.error('创建数据目录失败:', error);
    }
}

// 读取数据
app.get('/api/urls', async (req, res) => {
    try {
        await ensureDataDir();
        const data = await fs.readFile(DATA_FILE, 'utf8');
        res.json(JSON.parse(data));
    } catch (error) {
        if (error.code === 'ENOENT') {
            // 文件不存在，返回空数据
            res.json({ urls: [], categories: [] });
        } else {
            console.error('读取数据失败:', error);
            res.status(500).json({ error: '读取数据失败', message: error.message });
        }
    }
});

// 保存数据
app.post('/api/urls', async (req, res) => {
    try {
        await ensureDataDir();
        const data = {
            urls: req.body.urls || [],
            categories: req.body.categories || [],
            lastUpdated: new Date().toISOString()
        };
        
        console.log('收到保存请求:', {
            urlsCount: data.urls.length,
            categoriesCount: data.categories.length,
            timestamp: data.lastUpdated
        });
        
        await fs.writeFile(DATA_FILE, JSON.stringify(data, null, 2), 'utf8');
        
        // 验证文件是否写入成功
        const verifyData = await fs.readFile(DATA_FILE, 'utf8');
        const verifyJson = JSON.parse(verifyData);
        console.log('数据已保存，验证:', {
            urlsCount: verifyJson.urls.length,
            categoriesCount: verifyJson.categories.length
        });
        
        res.json({ success: true, message: '数据保存成功', savedCount: { urls: data.urls.length, categories: data.categories.length } });
    } catch (error) {
        console.error('保存数据失败:', error);
        res.status(500).json({ error: '保存数据失败', message: error.message });
    }
});

// 健康检查
app.get('/api/health', (req, res) => {
    res.json({ status: 'ok', timestamp: new Date().toISOString() });
});

// 启动服务器
app.listen(PORT, () => {
    console.log(`Workdizhi 服务器运行在端口 ${PORT}`);
    console.log(`数据文件位置: ${DATA_FILE}`);
});