const express = require('express');
const { Pool } = require('pg');
const neo4j = require('neo4j-driver');
const redis = require('redis');

const app = express();
app.use(express.json());

// PostgreSQL
const pgPool = new Pool({
  host: 'localhost',
  port: 5433,
  database: 'quixzoom',
  user: 'quixzoom',
  password: 'quixzoom_secure_2026'
});

// Neo4j
const neo4jDriver = neo4j.driver('bolt://localhost:7687', neo4j.auth.basic('neo4j', 'quixzoom_neo4j_2026'));

// Redis
const redisClient = redis.createClient({ url: 'redis://localhost:6380' });
redisClient.connect().catch(console.error);

// Health check
app.get('/health', async (req, res) => {
  const status = {
    status: 'ok',
    timestamp: new Date().toISOString(),
    services: {}
  };
  
  try {
    await pgPool.query('SELECT 1');
    status.services.postgresql = 'ok';
  } catch (e) {
    status.services.postgresql = 'error';
  }
  
  try {
    const session = neo4jDriver.session();
    await session.run('RETURN 1');
    await session.close();
    status.services.neo4j = 'ok';
  } catch (e) {
    status.services.neo4j = 'error';
  }
  
  try {
    await redisClient.ping();
    status.services.redis = 'ok';
  } catch (e) {
    status.services.redis = 'error';
  }
  
  res.json(status);
});

// Stats
app.get('/stats', async (req, res) => {
  try {
    const pgResult = await pgPool.query(`
      SELECT 
        (SELECT COUNT(*) FROM objects) as objects,
        (SELECT COUNT(*) FROM observations) as observations,
        (SELECT COUNT(*) FROM zoomers) as zoomers,
        (SELECT COUNT(*) FROM events) as events
    `);
    
    res.json({
      postgresql: pgResult.rows[0],
      timestamp: new Date().toISOString()
    });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

// Create object
app.post('/objects', async (req, res) => {
  try {
    const { object_id, type, latitude, longitude, attributes } = req.body;
    
    const result = await pgPool.query(
      'INSERT INTO objects (object_id, type, latitude, longitude, attributes) VALUES ($1, $2, $3, $4, $5) RETURNING *',
      [object_id, type, latitude, longitude, JSON.stringify(attributes || {})]
    );
    
    await pgPool.query(
      'INSERT INTO events (sequence_number, type, stream_id, aggregate_id, payload, timestamp) VALUES ((SELECT COALESCE(MAX(sequence_number), 0) + 1 FROM events), $1, $2, $3, $4, NOW())',
      ['ObjectRegistered', 'objects', object_id, JSON.stringify({ type, latitude, longitude, attributes })]
    );
    
    res.json(result.rows[0]);
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

// List objects
app.get('/objects', async (req, res) => {
  try {
    const result = await pgPool.query('SELECT * FROM objects ORDER BY created_at DESC LIMIT 100');
    res.json(result.rows);
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log('[API] QUIXZOOM API Server running on port ' + PORT);
  console.log('[API] Health: http://localhost:' + PORT + '/health');
  console.log('[API] Stats:  http://localhost:' + PORT + '/stats');
});