const express = require('express');
const { v4: uuidv4 } = require('uuid');
const db = require('../db');
const { logAudit } = require('../audit');
const router = express.Router();

// GET /api/rooms?siteId=
router.get('/', (req, res) => {
  const { siteId } = req.query;
  if (!siteId) return res.status(400).json({ error: 'siteId query param required' });

  const rooms = db.prepare(`
    SELECT r.*, COUNT(ra.id) as rack_count
    FROM rooms r
    LEFT JOIN racks ra ON ra.room_id = r.id
    WHERE r.site_id = ?
    GROUP BY r.id
    ORDER BY r.name
  `).all(siteId);
  res.json(rooms);
});

// GET /api/rooms/:id
router.get('/:id', (req, res) => {
  const room = db.prepare('SELECT * FROM rooms WHERE id = ?').get(req.params.id);
  if (!room) return res.status(404).json({ error: 'Room not found' });

  const racks = db.prepare(`
    SELECT ra.*, COUNT(c.id) as component_count
    FROM racks ra
    LEFT JOIN components c ON c.rack_id = ra.id
    WHERE ra.room_id = ?
    GROUP BY ra.id
    ORDER BY ra.name
  `).all(req.params.id);

  const site = db.prepare('SELECT id, name FROM sites WHERE id = ?').get(room.site_id);
  res.json({ ...room, racks, site });
});

// POST /api/rooms
router.post('/', (req, res) => {
  const { site_id, name, notes } = req.body;
  if (!site_id || !name) return res.status(400).json({ error: 'site_id and name are required' });

  const site = db.prepare('SELECT id FROM sites WHERE id = ?').get(site_id);
  if (!site) return res.status(404).json({ error: 'Site not found' });

  const id = uuidv4();
  db.prepare('INSERT INTO rooms (id, site_id, name, notes) VALUES (?, ?, ?, ?)').run(
    id, site_id, name, notes || ''
  );
  const created = db.prepare('SELECT * FROM rooms WHERE id = ?').get(id);
  logAudit(req, { action: 'create', entityType: 'room', entityId: id, entityName: name });
  res.status(201).json(created);
});

// PUT /api/rooms/:id
router.put('/:id', (req, res) => {
  const room = db.prepare('SELECT * FROM rooms WHERE id = ?').get(req.params.id);
  if (!room) return res.status(404).json({ error: 'Room not found' });

  const { name, notes } = req.body;
  const changes = {};
  if (name != null && name !== room.name) changes.name = { from: room.name, to: name };
  db.prepare(`
    UPDATE rooms SET name = ?, notes = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?
  `).run(name ?? room.name, notes ?? room.notes, req.params.id);

  logAudit(req, { action: 'update', entityType: 'room', entityId: room.id, entityName: name ?? room.name, changes });
  res.json(db.prepare('SELECT * FROM rooms WHERE id = ?').get(req.params.id));
});

// DELETE /api/rooms/:id
router.delete('/:id', (req, res) => {
  const room = db.prepare('SELECT * FROM rooms WHERE id = ?').get(req.params.id);
  if (!room) return res.status(404).json({ error: 'Room not found' });

  db.prepare('DELETE FROM rooms WHERE id = ?').run(req.params.id);
  logAudit(req, { action: 'delete', entityType: 'room', entityId: room.id, entityName: room.name });
  res.json({ ok: true });
});

module.exports = router;