[UI] Suggested pricing (#10867)

* Refactor NumberField into separate component

* Add helper func to ensure a number is a number

* Use placeholder value for suggested sale price

* Fix for auto-fill

* Tweak price calculation

* Add UI testing for sales order price breaks

* Fix aria label name

* Annotate price breaks to supplier part

* Fetch price break data

* Support price breaks for purchase order pricing

* Fix required to prevent circular imports

* Add playwright tests for purchase order price breaks

* Bump API version

* Re-add output options for SupplierPriceBreakList

* Revert change

* Simplify unit test

src/frontend/src/forms/PurchaseOrderForms.tsx

@@ -34,6 +34,7 @@ import { StandaloneField } from '../components/forms/StandaloneField';
 
 import { ProgressBar } from '@lib/components/ProgressBar';
 import { apiUrl } from '@lib/functions/Api';
+import { toNumber } from '@lib/functions/Conversion';
 import type {
   ApiFormAdjustFilterType,
   ApiFormFieldSet
@@ -58,19 +59,59 @@ import { useGlobalSettingsState } from '../states/SettingsStates';
 export function usePurchaseOrderLineItemFields({
   supplierId,
   orderId,
+  currency,
   create
 }: {
   supplierId?: number;
   orderId?: number;
+  currency?: string;
   create?: boolean;
 }) {
   const globalSettings = useGlobalSettingsState();
 
   const [purchasePrice, setPurchasePrice] = useState<string>('');
-  const [autoPricing, setAutoPricing] = useState(true);
+  const [purchasePriceCurrency, setPurchasePriceCurrency] = useState<string>(
+    currency ?? ''
+  );
+
+  const [autoPricing, setAutoPricing] = useState(false);
+
+  const [quantity, setQuantity] = useState<string>('1');
 
   // Internal part information
   const [part, setPart] = useState<any>({});
+  const [priceBreaks, setPriceBreaks] = useState<any[]>([]);
+  const [suggestedPurchasePrice, setSuggestedPurchasePrice] = useState<
+    string | undefined
+  >(undefined);
+
+  // Update suggested purchase price when part, quantity, or price breaks change
+  useEffect(() => {
+    // Only attempt to set purchase price for new line items
+    if (!create) return;
+
+    const qty = toNumber(quantity, null);
+
+    if (qty == null || qty <= 0) {
+      setSuggestedPurchasePrice(undefined);
+      return;
+    }
+
+    if (!part || !priceBreaks || priceBreaks.length === 0) {
+      setSuggestedPurchasePrice(undefined);
+      return;
+    }
+
+    const applicablePriceBreaks = priceBreaks
+      .filter((pb: any) => qty >= pb.quantity)
+      .sort((a: any, b: any) => b.quantity - a.quantity);
+
+    if (applicablePriceBreaks.length) {
+      setSuggestedPurchasePrice(applicablePriceBreaks[0].price);
+    } else {
+      setSuggestedPurchasePrice(undefined);
+    }
+  }, [create, part, quantity, priceBreaks]);
 
   useEffect(() => {
     if (autoPricing) {
@@ -95,9 +136,11 @@ export function usePurchaseOrderLineItemFields({
           part_detail: true,
           supplier_detail: true,
           active: true,
-          part_active: true
+          part_active: true,
+          price_breaks: true
         },
         onValueChange: (value, record) => {
+          setPriceBreaks(record?.price_breaks ?? []);
           setPart(record?.part_detail ?? {});
         },
         adjustFilters: (adjust: ApiFormAdjustFilterType) => {
@@ -108,14 +151,22 @@ export function usePurchaseOrderLineItemFields({
         }
       },
       reference: {},
-      quantity: {},
+      quantity: {
+        onValueChange: (value) => {
+          setQuantity(value);
+        }
+      },
       purchase_price: {
         icon: <IconCurrencyDollar />,
         value: purchasePrice,
+        placeholder: suggestedPurchasePrice,
+        placeholderAutofill: true,
         onValueChange: setPurchasePrice
       },
       purchase_price_currency: {
-        icon: <IconCoins />
+        icon: <IconCoins />,
+        value: purchasePriceCurrency,
+        onValueChange: setPurchasePriceCurrency
       },
       auto_pricing: {
         value: autoPricing,
@@ -162,7 +213,8 @@ export function usePurchaseOrderLineItemFields({
     globalSettings,
     supplierId,
     autoPricing,
-    purchasePrice
+    purchasePrice,
+    suggestedPurchasePrice
   ]);
 
   return fields;