feat(pdf): add 15% VAT line + VAT-inclusive Total to PO PDF

Co-authored-by: Orca <help@stably.ai>

src/lib/pdf/format.ts

@@ -57,7 +57,7 @@ export function quoteSubtotal(items: { quantity: number; selling_price: number }
  * `Subtotal` and the base of the `VAT (15%)` line.
  */
 export function poSubtotal(
-  items: { order_qty?: number | null; quantity: number; cost_price: number }[]
+  items: { order_qty?: number | null; quantity: number | null; cost_price: number }[]
 ): number {
   return Math.round(
     items.reduce(

src/lib/pdf/purchase-order-document.tsx

@@ -1,7 +1,7 @@
 import { Document, Page, View, Text, Image, StyleSheet } from "@react-pdf/renderer";
 import type { Letterhead } from "@/lib/letterhead";
 import type { OrderItem, Order, Supplier, PurchaseOrder } from "@/lib/types";
-import { formatZAR, formatDateLong } from "./format";
+import { formatZAR, formatDateLong, poSubtotal, vatAmount } from "./format";
 import { defaultAccentFor } from "@/lib/letterhead";
 
 /**
@@ -60,9 +60,13 @@ export interface PurchaseOrderDocumentProps {
  *     The customer's identity stays internal.
  *   - **No footer text** — keeps the document visually quiet and
  *     prevents accidental leakage of branch-specific marketing copy.
- *   - **No VAT line** — we pay what the supplier quotes, no markup
- *     math here. Different from the quote (customer-facing) where
- *     VAT is added on top of selling price.
+ *   - **VAT (15%) added to subtotal** — prints the supplier-quoted
+ *     subtotal, then VAT (15%), then a VAT-inclusive Total. Same
+ *     shape as the quote's totals block so the two documents feel
+ *     like siblings. The VAT-inclusive Total is the figure the
+ *     office uses for budget / VAT-return reconciliation; the stored
+ *     `purchase_orders.total_amount` stays VAT-ex (no PB schema
+ *     change).
  *
  * Description column uses `po_description` (supplier-facing copy),
  * NOT `description` (internal/operator copy). Falling back to
@@ -87,27 +91,21 @@ export function PurchaseOrderDocument({
       (letterhead.display_name?.toUpperCase().includes("CNL") ? "CNL" : "ISHERWOOD")
     );
 
-  // Subtotal = sum of (qty × cost) per line. Qty uses the same
-  // supplier-facing resolution as the line rows below — `order_qty`
-  // when the operator shorted or bumped a line, else falls back to
-  // the customer-facing `quantity` so a blank order_qty never zeroes
-  // a line. This keeps the printed line totals summing exactly to the
-  // Subtotal. We round to 2 dp so the table doesn't show floating-point
-  // dust (1.0000000003 R etc).
-  const subtotal = Math.round(
-    items.reduce(
-      (sum, it) =>
-        sum +
-        (Number(it.order_qty ?? it.quantity) || 0) *
-          (Number(it.cost_price) || 0),
-      0
-    ) * 100
-  ) / 100;
-  // Re-use the supplied snapshot if it differs from the live
-  // computation by < 0.01 — caller might have included an explicit
-  // total_amount that we want to honour (e.g. from the regenerate
-  // API where the PO record already has total_amount set).
-  const total = Math.abs(totalAmount - subtotal) < 0.01 ? totalAmount : subtotal;
+  // Subtotal = sum of (qty × cost) per line, using the
+  // `order_qty ?? quantity` supplier-facing fallback. Logic lives
+  // in `poSubtotal()` (src/lib/pdf/format.ts) so it's independently
+  // testable. This keeps the printed line totals summing exactly to the
+  // Subtotal.
+  const subtotal = poSubtotal(items);
+  // 15% VAT on top of the supplier-quoted subtotal — same helper the
+  // quote PDF uses, so both documents compute VAT identically. Total
+  // = subtotal + vat, rounded to 2dp so the line matches the printed
+  // figures exactly. The `totalAmount` prop (carried for API backwards
+  // compat with the existing route) is intentionally not used here:
+  // it holds the VAT-ex subtotal and there's nothing meaningful to
+  // reconcile against once the printed Total is `subtotal + vat`.
+  const vat = vatAmount(subtotal);
+  const totalInclVat = Math.round((subtotal + vat) * 100) / 100;
 
   return (
     <Document
@@ -219,18 +217,25 @@ export function PurchaseOrderDocument({
           })}
         </View>
 
-        {/* Totals — just Subtotal + Total. No VAT (we're buying, the
-            supplier's price is what we pay). Rule above Total mirrors
-            the quote's totals block so the two feel like siblings. */}
+        {/* Totals — Subtotal + VAT (15%) + rule + Total. Mirrors the
+            quote's totals block so the two PDFs feel like siblings
+            when filed side-by-side. `Subtotal` is the VAT-ex sum
+            (stored on `purchase_orders.total_amount`); the printed
+            `Total` is `subtotal × 1.15` — the figure the office
+            uses for budget / VAT-return reconciliation. */}
         <View style={styles.totals}>
           <View style={styles.totalLine}>
             <Text style={styles.totalLabel}>Subtotal:</Text>
             <Text style={styles.totalValue}>{formatZAR(subtotal)}</Text>
           </View>
+          <View style={styles.totalLine}>
+            <Text style={styles.totalLabel}>VAT (15%):</Text>
+            <Text style={styles.totalValue}>{formatZAR(vat)}</Text>
+          </View>
           <View style={styles.totalRule} />
           <View style={styles.totalLine}>
             <Text style={styles.totalFinalLabel}>Total:</Text>
-            <Text style={styles.totalFinalValue}>{formatZAR(total)}</Text>
+            <Text style={styles.totalFinalValue}>{formatZAR(totalInclVat)}</Text>
           </View>
         </View>
       </Page>