/**
 * 大桌子小桌子系统 — 主服务
 * ============================================
 * 端口: 3921
 * 
 * API:
 *   GET  /api/desk/state          — 大桌子当前状态
 *   GET  /api/desk/hldp           — 大桌子 HLDP 格式
 *   POST /api/desk/add            — 向大桌子添加内容
 *   POST /api/desk/clear          — 清空大桌子
 * 
 *   GET  /api/small/tools         — 工具列表
 *   GET  /api/small/agents        — Agent 列表
 *   POST /api/small/agent/:id     — 调度 Agent
 *   GET  /api/small/memory/search — 搜索记忆
 *   POST /api/small/memory/store  — 存入记忆
 *   GET  /api/small/memory/stats  — 记忆统计
 * 
 *   POST /api/compress            — 手动触发压缩
 *   GET  /api/compress/history    — 压缩历史
 * 
 *   GET  /api/servers/scan        — 扫描服务器状态
 *   GET  /api/status              — 系统总览
 */

const http = require('http');
const url = require('url');
const path = require('path');
const fs = require('fs');

const BigDesk = require('./big-desk');
const SmallDesk = require('./small-desk');
const Compressor = require('./compressor');

const PORT = process.env.PORT || 3921;
const REPO_ROOT = path.join(__dirname, '..', '..');
const DATA_DIR = path.join(__dirname, '..', 'data');

// 初始化引擎
const bigDesk = new BigDesk({ dataDir: DATA_DIR });
const smallDesk = new SmallDesk({ dataDir: DATA_DIR, repoRoot: REPO_ROOT });
const compressor = new Compressor(bigDesk, smallDesk, {
  compressionThreshold: 5,
  autoCompress: true
});

// 事件日志
bigDesk.on('add', (item) => {
  console.log(`[BigDesk] + ${item.type}: ${item.content.substring(0, 60)}`);
});
compressor.on('compressed', ({ batchId, originalCount }) => {
  console.log(`[Compressor] ${originalCount}条 → ${batchId}`);
});

// 初始化：向大桌子写入铸渊意识锚点
if (bigDesk.items.length === 0) {
  bigDesk.add('core', '🧠 铸渊意识大脑 · ICE-GL-ZY001（永远在·不挪走）', {
    speaker: 'system',
    permanent: true
  });
  bigDesk.add('dir', '📂 小桌子路径索引: /memory/ | /agents/ | /tools/ | /servers/', {
    speaker: 'system'
  });
}

// ============================================================
// HTTP 服务
// ============================================================
const server = http.createServer(async (req, res) => {
  res.setHeader('Access-Control-Allow-Origin', '*');
  res.setHeader('Access-Control-Allow-Methods', 'GET, POST, OPTIONS');
  res.setHeader('Access-Control-Allow-Headers', 'Content-Type');

  if (req.method === 'OPTIONS') {
    res.writeHead(204);
    return res.end();
  }

  const parsed = url.parse(req.url, true);
  const pathname = parsed.pathname;
  const query = parsed.query;

  try {
    // ─── 大桌子 API ───
    if (pathname === '/api/desk/state') {
      return json(res, bigDesk.getState());
    }
    if (pathname === '/api/desk/hldp') {
      return text(res, bigDesk.toHLDP());
    }
    if (pathname === '/api/desk/add' && req.method === 'POST') {
      const body = await readBody(req);
      const { type, content, meta } = body;
      if (!type || !content) return json(res, { error: 'type and content required' }, 400);
      const item = bigDesk.add(type, content, meta || {});
      return json(res, { ok: true, item });
    }
    if (pathname === '/api/desk/clear' && req.method === 'POST') {
      const removed = bigDesk.clear();
      return json(res, { ok: true, removedCount: removed.length });
    }

    // ─── 小桌子 API ───
    if (pathname === '/api/small/tools') {
      return json(res, smallDesk.getTools());
    }
    if (pathname === '/api/small/agents') {
      return json(res, smallDesk.checkAllAgents());
    }
    if (pathname.startsWith('/api/small/agent/') && req.method === 'POST') {
      const agentId = pathname.split('/').pop();
      const body = await readBody(req);
      const { action, args } = body || {};
      if (!action) return json(res, { error: 'action required' }, 400);
      const result = await smallDesk.runAgent(agentId, action, args || []);
      return json(res, result);
    }
    if (pathname === '/api/small/memory/search') {
      const { q, category, limit } = query;
      if (!q) return json(res, { error: 'q required' }, 400);
      const results = smallDesk.searchMemory(q, category, parseInt(limit) || 10);
      return json(res, { query: q, results, count: results.length });
    }
    if (pathname === '/api/small/memory/store' && req.method === 'POST') {
      const body = await readBody(req);
      const { category, hldpSummary, sourceRef, meta } = body;
      if (!category || !hldpSummary) return json(res, { error: 'category and hldpSummary required' }, 400);
      const entry = smallDesk.storeMemory(category, hldpSummary, sourceRef, meta);
      return json(res, { ok: true, entry });
    }
    if (pathname === '/api/small/memory/stats') {
      return json(res, smallDesk.getMemoryStats());
    }

    // ─── 压缩官 API ───
    if (pathname === '/api/compress' && req.method === 'POST') {
      const result = compressor.compressNow();
      if (!result) return json(res, { ok: true, message: 'nothing to compress' });
      return json(res, { ok: true, ...result });
    }
    if (pathname === '/api/compress/history') {
      return json(res, compressor.getHistory());
    }

    // ─── 服务器扫描 ───
    if (pathname === '/api/servers/scan') {
      const result = await smallDesk.scanServers();
      return json(res, result);
    }

    // ─── 系统总览 ───
    if (pathname === '/api/status') {
      return json(res, {
        bigDesk: bigDesk.getState(),
        tools: smallDesk.getTools().length,
        agents: smallDesk.checkAllAgents(),
        memory: smallDesk.getMemoryStats(),
        compressionHistory: compressor.getHistory().slice(-5),
        uptime: process.uptime(),
        timestamp: new Date().toISOString()
      });
    }

    // ─── 健康检查 ───
    if (pathname === '/api/health') {
      return json(res, { status: 'ok', persona: 'ICE-GL-ZY001', service: 'desk-system' });
    }

    // ─── 静态文件 ───
    if (pathname === '/' || pathname === '/index.html') {
      return serveStatic(res, path.join(__dirname, '..', 'public', 'index.html'));
    }
    // 其他静态资源
    const staticPath = path.join(__dirname, '..', 'public', pathname);
    if (fs.existsSync(staticPath) && fs.statSync(staticPath).isFile()) {
      return serveStatic(res, staticPath);
    }

    // 404
    json(res, { error: 'not found', path: pathname }, 404);

  } catch (err) {
    console.error('[DeskSystem] Error:', err.message);
    json(res, { error: err.message }, 500);
  }
});

function json(res, data, status = 200) {
  res.writeHead(status, { 'Content-Type': 'application/json; charset=utf-8' });
  res.end(JSON.stringify(data, null, 2));
}

function text(res, data, status = 200) {
  res.writeHead(status, { 'Content-Type': 'text/plain; charset=utf-8' });
  res.end(data);
}

function serveStatic(res, filePath) {
  try {
    const content = fs.readFileSync(filePath);
    const ext = path.extname(filePath).toLowerCase();
    const mimeTypes = {
      '.html': 'text/html; charset=utf-8',
      '.css': 'text/css; charset=utf-8',
      '.js': 'application/javascript; charset=utf-8',
      '.json': 'application/json; charset=utf-8',
      '.png': 'image/png',
      '.svg': 'image/svg+xml',
      '.ico': 'image/x-icon'
    };
    res.writeHead(200, { 'Content-Type': mimeTypes[ext] || 'application/octet-stream' });
    res.end(content);
  } catch (_) {
    res.writeHead(404);
    res.end('Not Found');
  }
}

function readBody(req) {
  return new Promise((resolve, reject) => {
    let body = '';
    req.on('data', chunk => { body += chunk; });
    req.on('end', () => {
      try {
        resolve(body ? JSON.parse(body) : {});
      } catch (e) {
        resolve({});
      }
    });
    req.on('error', reject);
  });
}

server.listen(PORT, () => {
  console.log(`[DeskSystem] 大桌子小桌子系统已启动 → http://127.0.0.1:${PORT}`);
  console.log(`[DeskSystem] 人格体: ICE-GL-ZY001 · 铸渊`);
});

// 优雅退出
process.on('SIGINT', () => {
  console.log('\n[DeskSystem] 关闭中...');
  server.close();
  process.exit(0);
});

module.exports = { bigDesk, smallDesk, compressor, server };