## Inventory and purchasing: products, warehouses, stock and purchase orders
<enumset name="OrderState">
<enum value="draft">Draft</enum>
<enum value="sent">Sent</enum>
<enum value="received">Received</enum>
</enumset>

Category @Catalog order="name"
   name d r

Product @Catalog order="name" defaultlisting="main"
   <filter name="category" property="category" display="primary" />
   <subset name="lowStock" order="name">
   <restriction expr="me.stock &lt; me.minimumStock" />
   </subset>
   <listing name="main">
   <tab name="all" label="All" />
   <tab name="lowStock" label="Low stock" subset="lowStock" />
   </listing>
   sku ds r "SKU"
   name d r
   category Category ds
   unitCost double r
   minimumStock integer default="0"
   stock integer ds fixed default="0"

Warehouse @Configuration order="name"
   name d r
   address

Supplier @Purchasing order="name"
   <subset name="active" order="name">
   <condition field="active" value="true" />
   </subset>
   name d r
   taxId r "Tax_ID"
   email
   active boolean default="true"

PurchaseOrder @Purchasing order="orderDate desc" defaultlisting="main"
   <subset name="sent" order="orderDate">
   <condition field="state" value="'sent'" />
   </subset>
   <listing name="main">
   <tab name="all" label="All" />
   <tab name="pending" label="Awaiting delivery" subset="sent" displayactions="receive" />
   </listing>
   <action name="receive" label="Receive" type="relatedentity" entity="ReceiveOrders" location="listing" defaultset="forOrders" />
   supplier Supplier d r subset="active"
   orderDate date ds r default="now"
   warehouse Warehouse r
   lines PurchaseOrderLine set ei x childproperty="purchaseOrder"
   total double ds calculated="sum(lines[*].amount)"
   state enum enumset="OrderState" default="draft" fixed

PurchaseOrderLine @
   purchaseOrder PurchaseOrder
   product Product r
   quantity integer r
   unitCost double r \
   <dynamicvalue expr="product.unitCost">
   <param name="product" entity="Product" value="product" />
   </dynamicvalue>
   amount double calculated="quantity * unitCost"

ReceiveOrders @ transient
   <defaultset name="forOrders">
   <param name="orders" entity="PurchaseOrder" collection="set" />
   <default name="orders" value="orders" />
   </defaultset>
   orders PurchaseOrder set fixed
   receivedOn date r default="now"
   notes text

StockMovement @Inventory order="id desc" noadd="noadd" noremove="noremove"
   product Product d fixed
   warehouse Warehouse ds fixed
   quantity integer ds fixed
   movedAt datetime ds fixed
   reason fixed