warehouse capacity and occupancy

app/inventory/api/engine/warehouse.php

@@ -3,17 +3,26 @@
 
     require '../../../assets/utils/db_auth.php';
 
-    $sql = "SELECT a.*, IFNULL(COUNT(DISTINCT b.product_sku), 0) AS unique_product, 
-            c.name AS manager_name, c.surname AS manager_surname
-        FROM md_warehouse a
-        LEFT JOIN warehouse_balance b ON
-            a.company_id = b.company_id AND
-            a.id = b.warehouse_id
-        LEFT JOIN wms.user c ON
-            a.manager = c.user_id
-        WHERE 
-            a.company_id = :company_id
-        GROUP BY a.id";
+    $sql = "SELECT 
+                a.*, 
+                COALESCE(r.total_racks, 0) AS capacity,
+                COALESCE(r.occupied_racks, 0) AS space_used,
+                COALESCE(r.unique_product, 0) AS unique_product,
+                c.name AS manager_name, 
+                c.surname AS manager_surname
+            FROM md_warehouse a
+            LEFT JOIN (
+                SELECT 
+                    company_id, warehouse,
+                    COUNT(*) AS total_racks,
+                    COUNT(product_sku) AS occupied_racks,
+                    COUNT(DISTINCT product_sku) AS unique_product
+                FROM md_rack
+                GROUP BY company_id, warehouse
+            ) r ON a.company_id = r.company_id AND a.id = r.warehouse
+            LEFT JOIN wms.user c ON a.manager = c.user_id
+            WHERE a.company_id = :company_id";
+
     $sth = $pdo2->prepare($sql);
     $sth->execute([
         ":company_id" => $company_id