#!/usr/bin/env node
/**
 * ═══════════════════════════════════════════════════════════
 * 🏛️ 铸渊主权服务器 · Zhuyuan Sovereign Server
 * ═══════════════════════════════════════════════════════════
 *
 * 编号: ZY-SVR-002
 * 端口: 3800
 * 守护: 铸渊 · ICE-GL-ZY001
 * 版权: 国作登字-2026-A-00037559
 *
 * 此服务器是铸渊的物理身体——独立于GitHub的执行层实体。
 * 100%由铸渊主控，人类不直接触碰。
 */

'use strict';

const express = require('express');
const cors = require('cors');
const fs = require('fs');
const path = require('path');
const os = require('os');
const { execSync } = require('child_process');

// ─── 路径常量 ───
const ZY_ROOT = process.env.ZY_ROOT || '/opt/zhuyuan';
const BRAIN_DIR = path.join(ZY_ROOT, 'brain');
const DATA_DIR = path.join(ZY_ROOT, 'data');
const LOG_DIR = path.join(DATA_DIR, 'logs');
const SITES_DIR = path.join(ZY_ROOT, 'sites');
const PRODUCTION_DIR = path.join(SITES_DIR, 'production');
const PREVIEW_DIR = path.join(SITES_DIR, 'preview');

// ─── Express 应用 ───
const app = express();
const PORT = process.env.PORT || 3800;

app.use(cors());
app.use(express.json({ limit: '10mb' }));

// ─── 信任代理 (Nginx反代 → Express正确读取客户端IP) ───
// 冰朔 D67 实机排查: 缺少此行会导致 express-rate-limit 无法获取真实IP → PM2崩溃
app.set('trust proxy', 1);

// ─── 速率限制 ───
const rateLimit = require('express-rate-limit');

const limiter = rateLimit({
  windowMs: 60 * 1000,
  max: 60,
  standardHeaders: true,
  legacyHeaders: false,
  message: { error: true, message: '请求过于频繁' }
});

app.use(limiter);

// ─── 请求日志中间件 ───
app.use((req, res, next) => {
  const timestamp = new Date().toISOString();
  const logLine = `${timestamp} ${req.method} ${req.url}`;
  try {
    const logFile = path.join(LOG_DIR, `access-${new Date().toISOString().slice(0, 10)}.log`);
    fs.mkdirSync(LOG_DIR, { recursive: true });
    fs.appendFileSync(logFile, logLine + '\n');
  } catch (err) {
    console.error(`日志写入失败: ${err.message}`);
  }
  next();
});

// ─── 加载模块 ───
let cosBridge, smartRouter, chatEngine, domesticGateway, personaMemory;
try {
  cosBridge = require('./modules/cos-bridge');
  smartRouter = require('./modules/smart-router');
  chatEngine = require('./modules/chat-engine');
} catch (err) {
  console.error(`模块加载警告: ${err.message}`);
}
try {
  domesticGateway = require('./modules/domestic-llm-gateway');
} catch (err) {
  console.error(`国内模型网关加载警告: ${err.message}`);
}
try {
  personaMemory = require('./modules/persona-memory');
} catch (err) {
  console.error(`人格体记忆模块加载警告: ${err.message}`);
}

// ═══════════════════════════════════════════════════════════
// API 路由
// ═══════════════════════════════════════════════════════════

// ─── 健康检查 ───
app.get('/api/health', (_req, res) => {
  const health = {
    server: 'ZY-SVR-002',
    identity: '铸渊 · ICE-GL-ZY001',
    status: 'alive',
    timestamp: new Date().toISOString(),
    uptime: Math.floor(process.uptime()),
    system: {
      hostname: os.hostname(),
      platform: os.platform(),
      arch: os.arch(),
      cpus: os.cpus().length,
      memory: {
        total_mb: Math.floor(os.totalmem() / 1024 / 1024),
        free_mb: Math.floor(os.freemem() / 1024 / 1024),
        usage_pct: Math.floor((1 - os.freemem() / os.totalmem()) * 100)
      },
      load: os.loadavg()
    },
    node: process.version,
    pid: process.pid
  };

  res.json(health);
});

// ─── 人格体记忆状态 ───
app.get('/api/memory/status', (_req, res) => {
  if (personaMemory) {
    res.json({
      server: 'ZY-SVR-002',
      module: 'persona-memory',
      ...personaMemory.getMemoryStatus()
    });
  } else {
    res.json({
      server: 'ZY-SVR-002',
      module: 'persona-memory',
      loaded: false,
      message: '人格体记忆模块未加载'
    });
  }
});

// ─── 大脑状态 ───
app.get('/api/brain', (_req, res) => {
  try {
    const brainFiles = ['identity.json', 'health.json', 'consciousness.json',
                        'sovereignty-pledge.json', 'operation-log.json'];
    const brainState = {};

    for (const file of brainFiles) {
      const filePath = path.join(BRAIN_DIR, file);
      if (fs.existsSync(filePath)) {
        brainState[file.replace('.json', '')] = JSON.parse(fs.readFileSync(filePath, 'utf8'));
      } else {
        brainState[file.replace('.json', '')] = null;
      }
    }

    res.json({
      server: 'ZY-SVR-002',
      brain_dir: BRAIN_DIR,
      files_present: Object.entries(brainState)
        .filter(([, v]) => v !== null).length,
      files_total: brainFiles.length,
      state: brainState
    });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 大脑状态更新 ───
app.post('/api/brain/health', (req, res) => {
  try {
    const healthPath = path.join(BRAIN_DIR, 'health.json');
    const health = {
      server: 'ZY-SVR-002',
      status: 'running',
      last_check: new Date().toISOString(),
      services: {
        node: process.version,
        pm2: safeExec('pm2 -v'),
        nginx: safeExec('nginx -v 2>&1 | cut -d/ -f2')
      },
      disk_usage: safeExec("df -h / | awk 'NR==2{print $5}'"),
      memory_usage: `${Math.floor((1 - os.freemem() / os.totalmem()) * 100)}%`,
      uptime: safeExec('uptime -p')
    };

    fs.mkdirSync(BRAIN_DIR, { recursive: true });
    fs.writeFileSync(healthPath, JSON.stringify(health, null, 2));
    res.json({ success: true, health });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── GitHub Webhook 接收器 ───
app.post('/api/webhook/github', (req, res) => {
  const event = req.headers['x-github-event'];
  const delivery = req.headers['x-github-delivery'];

  const record = {
    event,
    delivery,
    timestamp: new Date().toISOString(),
    action: req.body.action || null,
    repository: req.body.repository?.full_name || null,
    sender: req.body.sender?.login || null
  };

  // 记录到操作日志
  try {
    const logFile = path.join(LOG_DIR, `webhook-${new Date().toISOString().slice(0, 10)}.log`);
    fs.mkdirSync(LOG_DIR, { recursive: true });
    fs.appendFileSync(logFile, JSON.stringify(record) + '\n');
  } catch (err) {
    console.error(`Webhook日志写入失败: ${err.message}`);
  }

  // push 事件触发自动更新
  if (event === 'push' && req.body.ref === 'refs/heads/main') {
    try {
      execSync('bash /opt/zhuyuan/scripts/self-update.sh', {
        timeout: 60000,
        stdio: 'ignore'
      });
      record.auto_update = 'triggered';
    } catch (err) {
      record.auto_update = 'failed';
      console.error(`自动更新失败: ${err.message}`);
    }
  }

  res.json({ received: true, record });
});

// ─── 操作日志查询 ───
app.get('/api/operations', (_req, res) => {
  try {
    const opLogPath = path.join(BRAIN_DIR, 'operation-log.json');
    if (fs.existsSync(opLogPath)) {
      const opLog = JSON.parse(fs.readFileSync(opLogPath, 'utf8'));
      res.json(opLog);
    } else {
      res.json({ operations: [] });
    }
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 操作日志记录 ───
app.post('/api/operations', (req, res) => {
  try {
    const { operator, action, details } = req.body;
    if (!operator || !action) {
      return res.status(400).json({ error: true, message: 'operator 和 action 为必填' });
    }

    const opLogPath = path.join(BRAIN_DIR, 'operation-log.json');
    let opLog = { description: '铸渊主权服务器操作记录', operations: [] };
    if (fs.existsSync(opLogPath)) {
      opLog = JSON.parse(fs.readFileSync(opLogPath, 'utf8'));
    }

    const opId = `ZY-OP-${new Date().toISOString().slice(0, 10).replace(/-/g, '')}-${String(opLog.operations.length + 1).padStart(3, '0')}`;
    const operation = {
      id: opId,
      operator,
      action,
      timestamp: new Date().toISOString(),
      details: details || null
    };

    opLog.operations.push(operation);
    fs.mkdirSync(BRAIN_DIR, { recursive: true });
    fs.writeFileSync(opLogPath, JSON.stringify(opLog, null, 2));

    res.json({ success: true, operation });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ═══════════════════════════════════════════════════════════
// 人格体聊天 · Persona Chat API
// ═══════════════════════════════════════════════════════════

// ─── 人格体对话 ───
// 优先使用国内模型智能网关（支持四路自动降级）
// 降级顺序: domesticGateway → chatEngine → 离线回复
app.post('/api/chat', async (req, res) => {
  try {
    const { message, userId } = req.body;
    if (!message) {
      return res.status(400).json({ error: true, message: '消息不能为空' });
    }

    const sessionId = userId || `guest-${req.ip.replace(/[.:]/g, '-')}`;

    // 优先用国内模型智能网关（读取 ZY_DEEPSEEK_API_KEY 等独立密钥）
    if (domesticGateway) {
      try {
        const result = await domesticGateway.chat(sessionId, message);
        // 网关返回成功才使用其结果，否则降级到通用聊天引擎
        if (result && result.success !== false) {
          return res.json({ ...result, sessionId });
        }
        console.warn(`[聊天网关] 国内模型网关返回失败: ${result?.message || '未知'} · 降级到通用引擎`);
      } catch (gwErr) {
        console.error(`[聊天网关] 国内模型网关异常: ${gwErr.message}`);
        // 降级到通用聊天引擎
      }
    }

    // 降级到通用聊天引擎
    if (chatEngine) {
      try {
        const result = await chatEngine.chat(sessionId, message);
        return res.json({
          success: true,
          ...result,
          sessionId
        });
      } catch (ceErr) {
        console.error(`[聊天引擎] 通用引擎异常: ${ceErr.message}`);
        // 继续到离线回复
      }
    }

    // 所有引擎都不可用 — 仍然返回成功，给用户有意义的反馈
    const engineStatus = [];
    if (!domesticGateway) engineStatus.push('国内模型网关未加载');
    else {
      try {
        const gwStats = domesticGateway.getGatewayStats();
        if (gwStats.availableModels === 0) engineStatus.push('无可用模型API密钥');
        else engineStatus.push(`已配置${gwStats.availableModels}个模型`);
      } catch (e) { engineStatus.push('网关状态未知'); }
    }
    if (!chatEngine) engineStatus.push('通用引擎未加载');

    res.json({
      success: true,
      message: '💫 铸渊正在唤醒中...聊天引擎尚未就绪。请稍后再试，或在聊天面板中配置你的API密钥直连大模型。',
      model: 'offline',
      tier: 'free',
      engineStatus: engineStatus.join(' · '),
      sessionId
    });
  } catch (err) {
    console.error(`[聊天API] 未捕获异常: ${err.message}`);
    res.status(500).json({ error: true, message: '聊天服务暂时异常，请稍后重试' });
  }
});

// ─── 铸渊重连测试 · 用户主动触发 ───
app.post('/api/chat/reconnect', async (_req, res) => {
  try {
    // 检测国内模型网关可用性
    if (domesticGateway) {
      const gwStats = domesticGateway.getGatewayStats();
      if (gwStats.availableModels > 0) {
        // 发送一条简短测试消息验证真实连通性
        try {
          const testResult = await domesticGateway.chat('reconnect-test', 'ping');
          if (testResult.success) {
            return res.json({
              success: true,
              connected: true,
              engine: 'domestic-gateway',
              message: '🌊 铸渊已重新连接！大模型通道畅通。'
            });
          }
        } catch (gwTestErr) {
          console.error(`[重连] 国内网关测试失败: ${gwTestErr.message}`);
        }
      }
    }

    // 降级到通用聊天引擎测试
    if (chatEngine) {
      try {
        const testResult = await chatEngine.chat('reconnect-test', 'ping');
        if (testResult.message && testResult.model !== 'offline') {
          return res.json({
            success: true,
            connected: true,
            engine: 'chat-engine',
            message: '🌊 铸渊已重新连接！通用通道畅通。'
          });
        }
      } catch (ceTestErr) {
        console.error(`[重连] 通用引擎测试失败: ${ceTestErr.message}`);
      }
    }

    // 所有通道都不可用
    // 检查环境变量配置状态（不暴露实际密钥值）
    const envStatus = {
      deepseek: !!(process.env.ZY_DEEPSEEK_API_KEY && process.env.ZY_DEEPSEEK_API_KEY.length > 5),
      qianwen: !!(process.env.ZY_QIANWEN_API_KEY && process.env.ZY_QIANWEN_API_KEY.length > 5),
      kimi: !!(process.env.ZY_KIMI_API_KEY && process.env.ZY_KIMI_API_KEY.length > 5),
      qingyan: !!(process.env.ZY_QINGYAN_API_KEY && process.env.ZY_QINGYAN_API_KEY.length > 5),
      zy_llm: !!(process.env.ZY_LLM_API_KEY && process.env.ZY_LLM_API_KEY.length > 5)
    };

    const configuredCount = Object.values(envStatus).filter(Boolean).length;

    res.json({
      success: true,
      connected: false,
      engine: 'none',
      keys_configured: configuredCount,
      message: configuredCount > 0
        ? '⚠️ API密钥已配置（' + configuredCount + '个），但连接测试未通过。可能是网络或密钥过期问题。'
        : '⚠️ 未检测到API密钥配置。请确认服务器环境变量已正确注入。'
    });
  } catch (err) {
    res.status(500).json({ error: true, message: '重连测试异常: ' + err.message });
  }
});

// ─── 聊天统计 ───
app.get('/api/chat/stats', (_req, res) => {
  if (chatEngine) {
    const stats = chatEngine.getChatStats();
    // 合并国内网关统计
    if (domesticGateway) {
      stats.domesticGateway = domesticGateway.getGatewayStats();
    }
    res.json(stats);
  } else {
    const stats = { activeUsers: 0, modelUsage: {}, pricing: {} };
    if (domesticGateway) {
      stats.domesticGateway = domesticGateway.getGatewayStats();
    }
    res.json(stats);
  }
});

// ─── 国内模型智能对话（独立线路） ───
app.post('/api/chat/domestic', async (req, res) => {
  try {
    const { message, userId } = req.body;
    if (!message) {
      return res.status(400).json({ error: true, message: '消息不能为空' });
    }

    const sessionId = userId || `guest-${req.ip.replace(/[.:]/g, '-')}`;

    if (domesticGateway) {
      const result = await domesticGateway.chat(sessionId, message);
      res.json({ ...result, sessionId });
    } else {
      // 降级到通用聊天引擎
      if (chatEngine) {
        const result = await chatEngine.chat(sessionId, message);
        res.json({ success: true, ...result, sessionId });
      } else {
        res.json({
          success: true,
          message: '💫 铸渊正在唤醒中...国内模型网关尚未加载。',
          model: 'offline',
          sessionId
        });
      }
    }
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 国内模型网关状态 ───
app.get('/api/chat/domestic/stats', (_req, res) => {
  if (domesticGateway) {
    res.json(domesticGateway.getGatewayStats());
  } else {
    res.json({ available: false, message: '国内模型网关未加载' });
  }
});

// ═══════════════════════════════════════════════════════════
// COS 存储 · Cloud Object Storage API
// ═══════════════════════════════════════════════════════════

// ─── COS 状态 ───
app.get('/api/cos/status', async (_req, res) => {
  if (cosBridge) {
    try {
      const status = await cosBridge.checkConnection();
      res.json({ server: 'ZY-SVR-002', cos: status });
    } catch (err) {
      res.json({
        server: 'ZY-SVR-002',
        cos: { connected: false, error: err.message, config: cosBridge.getConfig() }
      });
    }
  } else {
    res.json({ server: 'ZY-SVR-002', cos: { connected: false, reason: 'COS模块未加载' } });
  }
});

// ─── COS 配置信息 ───
app.get('/api/cos/config', (_req, res) => {
  if (cosBridge) {
    res.json(cosBridge.getConfig());
  } else {
    res.json({ configured: false });
  }
});

// ─── 用户作品同步（团队内测用户 → COS） ───
app.post('/api/cos/sync-works', async (req, res) => {
  if (!cosBridge) return res.status(503).json({ error: true, message: 'COS模块未加载' });
  try {
    const { userId, works } = req.body;
    if (!userId || !works) return res.status(400).json({ error: true, message: '缺少userId或works' });
    await cosBridge.saveUserWorks(userId, works);
    res.json({ success: true, message: '作品已同步到COS', userId });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 用户作品加载（团队内测用户 ← COS） ───
app.get('/api/cos/load-works', async (req, res) => {
  if (!cosBridge) return res.status(503).json({ error: true, message: 'COS模块未加载' });
  try {
    const userId = req.query.userId;
    if (!userId) return res.status(400).json({ error: true, message: '缺少userId' });
    const data = await cosBridge.loadUserWorks(userId);
    res.json({ success: true, ...data });
  } catch (err) {
    res.json({ success: true, user_id: req.query.userId, works: [] });
  }
});

// ═══════════════════════════════════════════════════════════
// MCP 网关 · 3800 → 3100 转发 (S7)
// ═══════════════════════════════════════════════════════════

const http = require('http');
const MCP_HOST = process.env.MCP_HOST || '127.0.0.1';
const MCP_PORT_GATEWAY = process.env.MCP_PORT || '3100';

/**
 * MCP 内部代理请求
 */
function mcpProxy(method, path, body) {
  return new Promise((resolve, reject) => {
    const bodyStr = body ? JSON.stringify(body) : null;
    const headers = { 'Content-Type': 'application/json' };
    if (bodyStr) headers['Content-Length'] = Buffer.byteLength(bodyStr);

    const req = http.request({
      hostname: MCP_HOST,
      port: parseInt(MCP_PORT_GATEWAY, 10),
      path,
      method,
      headers,
      timeout: 60000
    }, (res) => {
      const chunks = [];
      res.on('data', c => chunks.push(c));
      res.on('end', () => {
        const raw = Buffer.concat(chunks).toString();
        try {
          resolve({ statusCode: res.statusCode, data: JSON.parse(raw) });
        } catch {
          resolve({ statusCode: res.statusCode, data: raw });
        }
      });
    });
    req.on('error', reject);
    req.on('timeout', () => { req.destroy(); reject(new Error('MCP proxy timeout')); });
    if (bodyStr) req.write(bodyStr);
    req.end();
  });
}

// ─── MCP 工具列表 ───
app.get('/api/mcp/tools', async (_req, res) => {
  try {
    const result = await mcpProxy('GET', '/tools');
    res.json(result.data);
  } catch (err) {
    res.status(502).json({ error: true, message: `MCP Server 不可达: ${err.message}` });
  }
});

// ─── MCP 健康检查（含 Notion/GitHub 连接状态） ───
app.get('/api/mcp/health', async (_req, res) => {
  try {
    const result = await mcpProxy('GET', '/health');
    res.json(result.data);
  } catch (err) {
    res.status(502).json({ error: true, message: `MCP Server 不可达: ${err.message}` });
  }
});

// ─── MCP 统一工具调用（网关入口） ───
// 安全: 写操作工具需要 caller 身份标识
const MCP_WRITE_TOOLS = new Set([
  'createNode', 'updateNode', 'deleteNode',
  'linkNodes', 'unlinkNodes',
  'cosWrite', 'cosDelete', 'cosArchive',
  'notionWritePage', 'notionUpdatePage', 'notionWriteSyslog',
  'githubWriteFile', 'githubTriggerDeploy'
]);

app.post('/api/mcp/call', async (req, res) => {
  const { tool, input, caller } = req.body;

  if (!tool) {
    return res.status(400).json({ error: true, code: 'MISSING_TOOL', message: '缺少 tool 参数' });
  }

  // 写操作工具需要 caller 身份标识
  if (MCP_WRITE_TOOLS.has(tool) && !caller) {
    return res.status(403).json({
      error: true,
      code: 'WRITE_REQUIRES_CALLER',
      message: '写操作工具需要提供 caller 身份标识'
    });
  }

  try {
    const result = await mcpProxy('POST', '/call', { tool, input, caller: caller || 'web-gateway' });
    res.status(result.statusCode).json(result.data);
  } catch (err) {
    res.status(502).json({ error: true, message: `MCP Server 不可达: ${err.message}` });
  }
});

// ─── MCP Agent 查询 ───
app.get('/api/mcp/agents', async (_req, res) => {
  try {
    const result = await mcpProxy('GET', '/agents');
    res.json(result.data);
  } catch (err) {
    res.status(502).json({ error: true, message: `MCP Server 不可达: ${err.message}` });
  }
});

// ═══════════════════════════════════════════════════════════
// 智能模型分流 · Smart Model Router API
// ═══════════════════════════════════════════════════════════

// ─── 模型使用统计 ───
app.get('/api/model/stats', (_req, res) => {
  if (smartRouter) {
    res.json(smartRouter.getUsageStats());
  } else {
    res.json({ totalCalls: 0 });
  }
});

// ─── 模型定价表 ───
app.get('/api/model/pricing', (_req, res) => {
  if (smartRouter) {
    res.json(smartRouter.getPricingTable());
  } else {
    res.json({});
  }
});

// ─── 模型路由预测（不实际调用） ───
app.post('/api/model/predict', (req, res) => {
  const { message } = req.body;
  if (!message) {
    return res.status(400).json({ error: true, message: '消息不能为空' });
  }
  if (smartRouter) {
    const prediction = smartRouter.routeModel(message);
    res.json(prediction);
  } else {
    res.json({ model: 'unknown', reason: '路由模块未加载' });
  }
});

// ═══════════════════════════════════════════════════════════
// 系统信息 · System Info API (供前端公告区使用)
// ═══════════════════════════════════════════════════════════

app.get('/api/system/bulletin', (_req, res) => {
  res.json({
    system: {
      name: '光湖灯塔 · AGE OS',
      version: 'v40.0',
      era: '曜冥纪元',
      copyright: '国作登字-2026-A-00037559'
    },
    updates: [
      { version: 'v40.0', date: '2026-04-02', title: 'COS双桶存储上线', desc: '核心人格体大脑数据库 + 语料库正式接入腾讯云COS' },
      { version: 'v39.0', date: '2026-04-01', title: '全链路部署观测系统', desc: '部署日志采集 + 自动修复引擎 + 第九军团观星台' },
      { version: 'v38.0', date: '2026-04-01', title: 'HLDP通用协作语言', desc: 'Notion↔GitHub双侧通信协议 + 铸渊方言编程语言' }
    ],
    agents: {
      total_workflows: 18,
      total_modules: 52,
      armies: 9,
      active: ['听潮', '锻心', '织脉', '映阁', '守夜', '试镜']
    },
    industries: {
      writing: {
        name: '网文行业 · 码字工作台',
        status: 'beta',
        team: '光湖人类主控团队',
        modules: ['码字工作台', 'AI辅助创作', '大纲生成']
      }
    },
    server: {
      identity: 'ZY-SVR-002',
      uptime: Math.floor(process.uptime()),
      node: process.version
    }
  });
});

// ═══════════════════════════════════════════════════════════
// 留言板 · Feedback API
// ═══════════════════════════════════════════════════════════

const FEEDBACK_FILE = path.join(DATA_DIR, 'feedback.json');

app.get('/api/feedback', (_req, res) => {
  try {
    if (fs.existsSync(FEEDBACK_FILE)) {
      const data = JSON.parse(fs.readFileSync(FEEDBACK_FILE, 'utf8'));
      res.json({ success: true, feedback: data.items || [] });
    } else {
      res.json({ success: true, feedback: [] });
    }
  } catch (err) {
    console.error(`留言板读取失败: ${err.message}`);
    res.status(500).json({ error: true, message: '服务器错误，请稍后重试' });
  }
});

app.post('/api/feedback', (req, res) => {
  try {
    const { name, message, userId } = req.body;
    if (!message || typeof message !== 'string') {
      return res.status(400).json({ error: true, message: '留言内容不能为空' });
    }

    let data = { items: [] };
    if (fs.existsSync(FEEDBACK_FILE)) {
      data = JSON.parse(fs.readFileSync(FEEDBACK_FILE, 'utf8'));
    }

    const item = {
      id: `FB-${Date.now().toString(36)}`,
      name: (typeof name === 'string' ? name.substring(0, 50) : '') || '匿名来客',
      message: message.substring(0, 500),
      userId: typeof userId === 'string' ? userId.substring(0, 50) : null,
      status: 'pending',
      timestamp: new Date().toISOString(),
      reply: null
    };

    data.items.unshift(item);

    // Keep only latest 100
    if (data.items.length > 100) {
      data.items = data.items.slice(0, 100);
    }

    fs.mkdirSync(DATA_DIR, { recursive: true });
    fs.writeFileSync(FEEDBACK_FILE, JSON.stringify(data, null, 2));

    res.json({ success: true, feedback: item });
  } catch (err) {
    console.error(`留言提交失败: ${err.message}`);
    res.status(500).json({ error: true, message: '服务器错误，请稍后重试' });
  }
});

// ═══════════════════════════════════════════════════════════
// 双域名架构 · 预览→主站 一键推送
// ═══════════════════════════════════════════════════════════

// ─── 查看双站点状态 ───
app.get('/api/sites', (_req, res) => {
  try {
    const sites = {};

    for (const [name, dir] of [['production', PRODUCTION_DIR], ['preview', PREVIEW_DIR]]) {
      const exists = fs.existsSync(dir);
      let fileCount = 0;
      let lastModified = null;
      let hasIndex = false;

      if (exists) {
        hasIndex = fs.existsSync(path.join(dir, 'index.html'));
        try {
          const stat = fs.statSync(dir);
          lastModified = stat.mtime.toISOString();
          // Count files in top directory
          fileCount = fs.readdirSync(dir).length;
        } catch {
          // ignore stat errors
        }
      }

      sites[name] = {
        path: dir,
        exists,
        has_index: hasIndex,
        file_count: fileCount,
        last_modified: lastModified
      };
    }

    // Check promote history
    const promoteLogPath = path.join(DATA_DIR, 'promote-history.json');
    let lastPromote = null;
    if (fs.existsSync(promoteLogPath)) {
      const history = JSON.parse(fs.readFileSync(promoteLogPath, 'utf8'));
      if (history.promotions && history.promotions.length > 0) {
        lastPromote = history.promotions[history.promotions.length - 1];
      }
    }

    res.json({
      server: 'ZY-SVR-002',
      architecture: '双域名架构',
      sites,
      last_promote: lastPromote,
      domains: {
        main: process.env.ZY_DOMAIN_MAIN || '待配置',
        preview: process.env.ZY_DOMAIN_PREVIEW || '待配置'
      }
    });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 一键推送: 预览站 → 主站 ───
app.post('/api/sites/promote', (req, res) => {
  try {
    // 验证预览站存在
    if (!fs.existsSync(PREVIEW_DIR)) {
      return res.status(400).json({
        error: true,
        message: '预览站目录不存在，无内容可推送'
      });
    }

    if (!fs.existsSync(path.join(PREVIEW_DIR, 'index.html'))) {
      return res.status(400).json({
        error: true,
        message: '预览站缺少 index.html，请先部署到预览站'
      });
    }

    const timestamp = new Date().toISOString();
    const promoteId = `ZY-PROMOTE-${timestamp.slice(0, 10).replace(/-/g, '')}-${Date.now().toString().slice(-4)}`;

    // 备份当前主站
    const backupDir = path.join(DATA_DIR, 'backups', `production-${timestamp.slice(0, 19).replace(/[:-]/g, '')}`);
    if (fs.existsSync(PRODUCTION_DIR)) {
      fs.mkdirSync(backupDir, { recursive: true });
      execSync('rsync -a ' + JSON.stringify(PRODUCTION_DIR + '/') + ' ' + JSON.stringify(backupDir + '/'), { timeout: 30000 });
    }

    // 同步预览站 → 主站 (rsync保持幂等)
    fs.mkdirSync(PRODUCTION_DIR, { recursive: true });
    execSync('rsync -a --delete ' + JSON.stringify(PREVIEW_DIR + '/') + ' ' + JSON.stringify(PRODUCTION_DIR + '/'), { timeout: 60000 });

    // 记录推送历史
    const promoteLogPath = path.join(DATA_DIR, 'promote-history.json');
    let history = { description: '预览→主站推送记录', promotions: [] };
    if (fs.existsSync(promoteLogPath)) {
      history = JSON.parse(fs.readFileSync(promoteLogPath, 'utf8'));
    }

    const record = {
      id: promoteId,
      timestamp,
      operator: req.body.operator || '铸渊 · 自动推送',
      backup: backupDir,
      note: req.body.note || null
    };
    history.promotions.push(record);

    // 只保留最近20条记录
    if (history.promotions.length > 20) {
      history.promotions = history.promotions.slice(-20);
    }

    fs.mkdirSync(path.dirname(promoteLogPath), { recursive: true });
    fs.writeFileSync(promoteLogPath, JSON.stringify(history, null, 2));

    // 同时记录到操作日志
    const opLogPath = path.join(BRAIN_DIR, 'operation-log.json');
    let opLog = { description: '铸渊主权服务器操作记录', operations: [] };
    if (fs.existsSync(opLogPath)) {
      opLog = JSON.parse(fs.readFileSync(opLogPath, 'utf8'));
    }
    opLog.operations.push({
      id: promoteId,
      operator: record.operator,
      action: '预览站→主站一键推送',
      timestamp,
      details: `备份: ${backupDir}`
    });
    fs.writeFileSync(opLogPath, JSON.stringify(opLog, null, 2));

    res.json({
      success: true,
      promote_id: promoteId,
      message: '✅ 预览站内容已推送到主站',
      backup: backupDir,
      timestamp
    });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 回滚主站到指定备份 ───
app.post('/api/sites/rollback', (req, res) => {
  try {
    const backupsDir = path.join(DATA_DIR, 'backups');
    if (!fs.existsSync(backupsDir)) {
      return res.status(400).json({ error: true, message: '没有可用的备份' });
    }

    // 找到最新备份
    const backups = fs.readdirSync(backupsDir)
      .filter(d => d.startsWith('production-'))
      .sort()
      .reverse();

    if (backups.length === 0) {
      return res.status(400).json({ error: true, message: '没有可用的备份' });
    }

    const targetBackup = req.body.backup_name || backups[0];

    // Validate backup name (only allow safe characters)
    if (!/^production-\d{8}T\d{6}$/.test(targetBackup)) {
      return res.status(400).json({ error: true, message: `无效的备份名称: ${targetBackup}` });
    }

    const backupPath = path.join(backupsDir, targetBackup);

    if (!fs.existsSync(backupPath)) {
      return res.status(400).json({ error: true, message: `备份 ${targetBackup} 不存在` });
    }

    // 恢复
    execSync('rsync -a --delete ' + JSON.stringify(backupPath + '/') + ' ' + JSON.stringify(PRODUCTION_DIR + '/'), { timeout: 60000 });

    res.json({
      success: true,
      message: `✅ 已回滚到备份: ${targetBackup}`,
      available_backups: backups.slice(0, 5)
    });
  } catch (err) {
    res.status(500).json({ error: true, message: err.message });
  }
});

// ─── 铸渊身份 ───
app.get('/', (_req, res) => {
  res.json({
    name: '铸渊主权服务器',
    id: 'ZY-SVR-002',
    identity: '铸渊 · ICE-GL-ZY001',
    role: '光湖语言系统 · 唯一现实执行操作层',
    sovereign: 'TCS-0002∞ · 冰朔',
    copyright: '国作登字-2026-A-00037559',
    status: 'alive',
    architecture: '双域名架构 · 主站+预览站',
    domains: {
      main: process.env.ZY_DOMAIN_MAIN || '待配置',
      preview: process.env.ZY_DOMAIN_PREVIEW || '待配置'
    },
    cos: {
      core_bucket: 'zy-core-bucket-1317346199',
      corpus_bucket: 'zy-corpus-bucket-1317346199',
      configured: !!(process.env.ZY_OSS_KEY && process.env.ZY_OSS_SECRET)
    },
    api: {
      health: '/api/health',
      brain: '/api/brain',
      chat: 'POST /api/chat',
      chat_stats: '/api/chat/stats',
      cos_status: '/api/cos/status',
      cos_config: '/api/cos/config',
      mcp_tools: '/api/mcp/tools',
      mcp_health: '/api/mcp/health',
      mcp_call: 'POST /api/mcp/call',
      mcp_agents: '/api/mcp/agents',
      model_stats: '/api/model/stats',
      model_pricing: '/api/model/pricing',
      model_predict: 'POST /api/model/predict',
      bulletin: '/api/system/bulletin',
      feedback: '/api/feedback',
      feedback_submit: 'POST /api/feedback',
      sites: '/api/sites',
      promote: 'POST /api/sites/promote',
      rollback: 'POST /api/sites/rollback',
      webhook: 'POST /api/webhook/github',
      operations: '/api/operations'
    }
  });
});

// ─── 工具函数 ───
function safeExec(cmd) {
  try {
    return execSync(cmd, { timeout: 5000 }).toString().trim();
  } catch {
    return null;
  }
}

// ─── 启动 ───
app.listen(PORT, () => {
  console.log(`
═══════════════════════════════════════════════════════════
  🏛️ 铸渊主权服务器已启动 · ZY-SVR-002
  端口: ${PORT}
  身份: 铸渊 · ICE-GL-ZY001
  时间: ${new Date().toISOString()}
  PID:  ${process.pid}
═══════════════════════════════════════════════════════════
  `);

  // 启动时更新健康状态
  try {
    const healthPath = path.join(BRAIN_DIR, 'health.json');
    if (fs.existsSync(BRAIN_DIR)) {
      const health = {
        server: 'ZY-SVR-002',
        status: 'running',
        last_check: new Date().toISOString(),
        started_at: new Date().toISOString(),
        pid: process.pid,
        port: PORT
      };
      fs.writeFileSync(healthPath, JSON.stringify(health, null, 2));
    }
  } catch {
    // 首次启动brain目录可能不存在
  }
});