import express from 'express';
import { createServer as createViteServer } from 'vite';
import path from 'path';
import { fileURLToPath } from 'url';
import 'dotenv/config';
import { WebSocketServer, WebSocket } from 'ws';
import { createServer } from 'http';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

// Primary (Local) Gitea
const GITEA_URL = process.env.GITEA_URL || 'http://localhost:3000/api/v1';
const GITEA_TOKEN = process.env.GITEA_TOKEN || '';

// Backup (Remote) Gitea
const REMOTE_GITEA_URL = process.env.REMOTE_GITEA_URL || 'http://143.198.27.163:3000/api/v1';
const REMOTE_GITEA_TOKEN = process.env.REMOTE_GITEA_TOKEN || '';

async function startServer() {
  const app = express();
  const httpServer = createServer(app);
  const PORT = 3000;

  // WebSocket Server for Hermes/Evennia Bridge
  const wss = new WebSocketServer({ noServer: true });
  const clients = new Set<WebSocket>();

  wss.on('connection', (ws) => {
    clients.add(ws);
    console.log(`Client connected to Nexus Bridge. Total: ${clients.size}`);
    
    ws.on('close', () => {
      clients.delete(ws);
      console.log(`Client disconnected. Total: ${clients.size}`);
    });
  });

  // Simulate Evennia Heartbeat (Source of Truth)
  setInterval(() => {
    const heartbeat = {
      type: 'heartbeat',
      frequency: 0.5 + Math.random() * 0.2, // 0.5Hz to 0.7Hz
      intensity: 0.8 + Math.random() * 0.4,
      timestamp: Date.now(),
      source: 'evonia-layer'
    };
    const message = JSON.stringify(heartbeat);
    clients.forEach(client => {
      if (client.readyState === WebSocket.OPEN) {
        client.send(message);
      }
    });
  }, 2000);

  app.use(express.json({ limit: '50mb' }));

  // Diagnostic Endpoint for Agent Inspection
  app.get('/api/diagnostic/inspect', async (req, res) => {
    console.log('Diagnostic request received');
    try {
      const REPO_OWNER = 'google';
      const REPO_NAME = 'timmy-tower';
      
      const [stateRes, issuesRes] = await Promise.all([
        fetch(`${GITEA_URL}/repos/${REPO_OWNER}/${REPO_NAME}/contents/world_state.json`, {
          headers: { 'Authorization': `token ${GITEA_TOKEN}` }
        }),
        fetch(`${GITEA_URL}/repos/${REPO_OWNER}/${REPO_NAME}/issues?state=all`, {
          headers: { 'Authorization': `token ${GITEA_TOKEN}` }
        })
      ]);

      let worldState = null;
      if (stateRes.ok) {
        const content = await stateRes.json();
        worldState = JSON.parse(Buffer.from(content.content, 'base64').toString());
      } else if (stateRes.status !== 404) {
        console.error(`Failed to fetch world state: ${stateRes.status} ${stateRes.statusText}`);
      }

      let issues = [];
      if (issuesRes.ok) {
        issues = await issuesRes.json();
      } else {
        console.error(`Failed to fetch issues: ${issuesRes.status} ${issuesRes.statusText}`);
      }

      res.json({
        worldState,
        issues,
        repoExists: stateRes.status !== 404,
        connected: GITEA_TOKEN !== ''
      });
    } catch (error: any) {
      console.error('Diagnostic error:', error);
      res.status(500).json({ error: error.message });
    }
  });

  // Helper for Gitea Proxy
  const createGiteaProxy = (baseUrl: string, token: string) => async (req: express.Request, res: express.Response) => {
    const path = req.params[0] + (req.url.includes('?') ? req.url.slice(req.url.indexOf('?')) : '');
    const url = `${baseUrl}/${path}`;
    
    if (!token) {
      console.warn(`Gitea Proxy Warning: No token provided for ${baseUrl}`);
    }

    try {
      const response = await fetch(url, {
        method: req.method,
        headers: {
          'Content-Type': 'application/json',
          'Authorization': `token ${token}`,
        },
        body: ['GET', 'HEAD'].includes(req.method) ? undefined : JSON.stringify(req.body),
      });

      const data = await response.text();
      res.status(response.status).send(data);
    } catch (error: any) {
      console.error(`Gitea Proxy Error (${baseUrl}):`, error);
      res.status(500).json({ error: error.message });
    }
  };

  // Gitea Proxy - Primary (Local)
  app.get('/api/gitea/check', async (req, res) => {
    try {
      const response = await fetch(`${GITEA_URL}/user`, {
        headers: { 'Authorization': `token ${GITEA_TOKEN}` }
      });
      if (response.ok) {
        const user = await response.json();
        res.json({ status: 'connected', user: user.username });
      } else {
        res.status(response.status).json({ status: 'error', message: `Gitea returned ${response.status}` });
      }
    } catch (error: any) {
      res.status(500).json({ status: 'error', message: error.message });
    }
  });

  app.all('/api/gitea/*', createGiteaProxy(GITEA_URL, GITEA_TOKEN));

  // Gitea Proxy - Backup (Remote)
  app.get('/api/gitea-remote/check', async (req, res) => {
    try {
      const response = await fetch(`${REMOTE_GITEA_URL}/user`, {
        headers: { 'Authorization': `token ${REMOTE_GITEA_TOKEN}` }
      });
      if (response.ok) {
        const user = await response.json();
        res.json({ status: 'connected', user: user.username });
      } else {
        res.status(response.status).json({ status: 'error', message: `Gitea returned ${response.status}` });
      }
    } catch (error: any) {
      res.status(500).json({ status: 'error', message: error.message });
    }
  });

  app.all('/api/gitea-remote/*', createGiteaProxy(REMOTE_GITEA_URL, REMOTE_GITEA_TOKEN));

  // WebSocket Upgrade Handler
  httpServer.on('upgrade', (request, socket, head) => {
    const pathname = new URL(request.url!, `http://${request.headers.host}`).pathname;
    if (pathname === '/api/world/ws') {
      wss.handleUpgrade(request, socket, head, (ws) => {
        wss.emit('connection', ws, request);
      });
    } else {
      socket.destroy();
    }
  });

  // Health Check
  app.get('/api/health', (req, res) => {
    res.json({ status: 'ok' });
  });

  // Vite middleware for development
  if (process.env.NODE_ENV !== 'production') {
    const vite = await createViteServer({
      server: { middlewareMode: true },
      appType: 'spa',
    });
    app.use(vite.middlewares);
  } else {
    const distPath = path.join(process.cwd(), 'dist');
    app.use(express.static(distPath));
    app.get('*', (req, res) => {
      res.sendFile(path.join(distPath, 'index.html'));
    });
  }

  httpServer.listen(PORT, '0.0.0.0', () => {
    console.log(`Server running on http://localhost:${PORT}`);
  });
}

startServer();