<?php
/**
 * alert_low_stock.php — Called by Node.js scheduler daily at 8am.
 * Returns companies that have one or more low-stock products.
 * Response: { success: 1, alerts: [{ company_id, count }] }
 */
require __DIR__ . '/../assets/utils/cron_auth.php';

// Same rule as ReportManager::getLowStockItems(): counted per warehouse, at or
// below the higher of reorder point and minimum stock.
$sth = $pdo2->query(
    "SELECT e.company_id, COUNT(*) AS count
      FROM (
          SELECT company_id, warehouse_id, product_sku, SUM(total_in - total_out) AS balance
          FROM etl_stock_summary
          WHERE company_id > 0
          GROUP BY company_id, warehouse_id, product_sku
      ) e
      JOIN md_product p
        ON p.sku        = e.product_sku
       AND p.company_id = e.company_id
       AND p.status     > 0
      JOIN md_warehouse w
        ON w.id         = e.warehouse_id
       AND w.company_id = e.company_id
       AND w.status     = 1
      WHERE GREATEST(p.reorder_point, p.min_stock) > 0
        AND e.balance <= GREATEST(p.reorder_point, p.min_stock)
      GROUP BY e.company_id
      HAVING count > 0"
);

$answer['success'] = 1;
$answer['alerts']  = $sth->fetchAll(PDO::FETCH_ASSOC);

exit(json_encode($answer));