import { sql } from '../../../lib/sql.js';
import { getUserFromRequest } from '../../../lib/permission-middleware.js';
import { checkStoresRateLimit } from '../../../lib/rate-limit.js';
import { getZipCoords, getStoresNear } from '../../../lib/pricing/geo-cache.js';
import { clampRadiusMiles, milesToMeters } from '../../../lib/pricing/overpass.js';

function isLocalPricingEnabled() {
  const flag = process.env.PRICING_LOCAL_ENABLED;
  return flag === undefined || flag === '' || flag === 'true';
}

export default async function handler(req, res) {
  if (req.method !== 'GET') {
    return res.status(405).json({ error: 'Method not allowed' });
  }

  if (!isLocalPricingEnabled()) {
    return res.status(503).json({ error: 'Local store discovery is disabled' });
  }

  try {
    const user = await getUserFromRequest(req);
    if (!user) {
      return res.status(401).json({ error: 'Authentication required' });
    }

    const rateLimit = await checkStoresRateLimit(req, user.userId);
    if (!rateLimit.allowed) {
      const retryAfterSec = Math.max(1, Math.ceil((rateLimit.reset - Date.now()) / 1000));
      res.setHeader('Retry-After', String(retryAfterSec));
      return res.status(429).json({ error: 'Rate limit exceeded' });
    }

    const userRow = await sql`
      SELECT home_zip
      FROM users
      WHERE id = ${user.userId}
      LIMIT 1
    `;

    if (userRow.rows.length === 0) {
      return res.status(404).json({ error: 'User not found' });
    }

    const homeZip = userRow.rows[0].home_zip;
    if (!homeZip) {
      return res.status(400).json({ error: 'Home ZIP not configured', code: 'NO_HOME_ZIP' });
    }

    const radiusMiles = clampRadiusMiles(
      req.query.radiusMiles != null ? Number(req.query.radiusMiles) : undefined
    );
    const radiusMeters = milesToMeters(radiusMiles);

    const coords = await getZipCoords(homeZip);
    if (!coords) {
      return res.status(404).json({ error: 'Could not geocode home ZIP' });
    }

    const { stores, cached } = await getStoresNear(coords.lat, coords.lng, radiusMeters);

    return res.status(200).json({
      homeZip,
      radiusMiles,
      stores,
      cached,
      coordsCached: coords.cached,
    });
  } catch (error) {
    console.error('[stores/nearby]', error);
    return res.status(500).json({ error: 'Internal server error' });
  }
}