feat(stock-purchases): aggregate ordered/received value on list rows

Add ordered_value and received_value to StockPurchaseListRow. Each is
Σ line.{quantity|quantity_received} × line.cost_price, rounded to 2dp.
Replaces countItemsForPurchase with summarizeItemsForPurchase so the
per-row N+1 returns all three numbers in one fetch (no extra round
trip).

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

src/lib/server/stock-purchases-service.test.ts

@@ -718,3 +718,97 @@ describe("receiveStockPurchase", () => {
     }
   });
 });
+
+// ============================================================================
+// listStockPurchases — total value aggregation
+// ============================================================================
+
+describe("listStockPurchases — total value", () => {
+  async function seedPurchaseWithItems(pb: typeof pbMock, id: string, items: Array<{
+    quantity: number;
+    quantity_received: number;
+    cost_price: number;
+  }>) {
+    await pb.collection("stock_purchases").create({
+      id,
+      purchase_number: `PO26000100STK-${id}`,
+      supplier: "sup-1",
+      status: "draft",
+      notes: "",
+      email_error: "",
+      email_message_id: "",
+    });
+    for (const item of items) {
+      await pb.collection("stock_purchase_items").create({
+        purchase: id,
+        stock_item: "si-1",
+        description: "Widget",
+        ...item,
+        notes: "",
+      });
+    }
+  }
+
+  it("returns ordered_value = Σ quantity × cost_price across lines", async () => {
+    await seedPurchaseWithItems(pbMock, "sp-a", [
+      { quantity: 10, quantity_received: 0, cost_price: 12.5 },
+      { quantity: 4, quantity_received: 0, cost_price: 99 },
+    ]);
+    const { items } = await listStockPurchases(pbMock);
+    const row = items.find((r) => r.id === "sp-a")!;
+    expect(row.ordered_value).toBe(521); // 125 + 396
+  });
+
+  it("returns received_value = Σ quantity_received × cost_price across lines", async () => {
+    await seedPurchaseWithItems(pbMock, "sp-a", [
+      { quantity: 10, quantity_received: 6, cost_price: 12.5 },
+      { quantity: 4, quantity_received: 4, cost_price: 99 },
+    ]);
+    const { items } = await listStockPurchases(pbMock);
+    const row = items.find((r) => r.id === "sp-a")!;
+    expect(row.received_value).toBe(471); // 75 + 396
+  });
+
+  it("rounds ordered_value and received_value to 2dp", async () => {
+    await seedPurchaseWithItems(pbMock, "sp-a", [
+      { quantity: 3, quantity_received: 1, cost_price: 0.1 + 0.2 }, // 0.30000000000000004
+    ]);
+    const { items } = await listStockPurchases(pbMock);
+    const row = items.find((r) => r.id === "sp-a")!;
+    expect(row.ordered_value).toBe(0.9);
+    expect(row.received_value).toBe(0.3);
+  });
+
+  it("returns { ordered_value: 0, received_value: 0 } when a purchase has no lines", async () => {
+    await pbMock.collection("stock_purchases").create({
+      id: "sp-empty",
+      purchase_number: "PO26000200STK",
+      supplier: "sup-1",
+      status: "draft",
+      notes: "",
+      email_error: "",
+      email_message_id: "",
+    });
+    const { items } = await listStockPurchases(pbMock);
+    const row = items.find((r) => r.id === "sp-empty")!;
+    expect(row.ordered_value).toBe(0);
+    expect(row.received_value).toBe(0);
+    expect(row.item_count).toBe(0);
+  });
+
+  it("computes each row's totals from its own items only (no cross-row leakage)", async () => {
+    await seedPurchaseWithItems(pbMock, "sp-x", [
+      { quantity: 1, quantity_received: 1, cost_price: 100 },
+    ]);
+    await seedPurchaseWithItems(pbMock, "sp-y", [
+      { quantity: 2, quantity_received: 2, cost_price: 50 },
+    ]);
+    const { items } = await listStockPurchases(pbMock);
+    const x = items.find((r) => r.id === "sp-x")!;
+    const y = items.find((r) => r.id === "sp-y")!;
+    expect(x.ordered_value).toBe(100);
+    expect(x.received_value).toBe(100);
+    expect(y.ordered_value).toBe(100);
+    expect(y.received_value).toBe(100);
+  });
+});

src/lib/server/stock-purchases-service.ts

@@ -161,6 +161,19 @@ export interface ListStockPurchasesOpts {
 
 export interface StockPurchaseListRow extends StockPurchase {
   item_count: number;
+  /**
+   * Sum of `line.quantity * line.cost_price` across every line on
+   * this purchase. Reflects the value committed to the supplier —
+   * visible from draft stage onwards. Rounded to 2dp (matches
+   * `calculateTotals` in `pb-helpers.ts`).
+   */
+  ordered_value: number;
+  /**
+   * Sum of `line.quantity_received * line.cost_price`. Zero for
+   * drafts; grows as goods are booked into stock via collection-confirm.
+   * Lets the operator spot short-shipped POs at a glance.
+   */
+  received_value: number;
 }
 
 /**
@@ -189,8 +202,13 @@ export async function listStockPurchases(
   // `line_count` on the header.
   const items: StockPurchaseListRow[] = [];
   for (const row of result.items) {
-    const lineCount = await countItemsForPurchase(pb, String(row.id));
-    items.push({ ...(row as unknown as StockPurchase), item_count: lineCount });
+    const summary = await summarizeItemsForPurchase(pb, String(row.id));
+    items.push({
+      ...(row as unknown as StockPurchase),
+      item_count: summary.count,
+      ordered_value: summary.ordered,
+      received_value: summary.received,
+    });
   }
 
   return {
@@ -202,14 +220,39 @@ export async function listStockPurchases(
   };
 }
 
-async function countItemsForPurchase(
+/**
+ * Fetch all `stock_purchase_items` rows for a single purchase and
+ * return the line count plus the two value aggregates the list
+ * table needs. Pulls `quantity`, `quantity_received`, and
+ * `cost_price` in one round-trip; replacing the older id-only
+ * helper so the cost is the same.
+ */
+async function summarizeItemsForPurchase(
   pb: StockPurchasesPb,
   purchaseId: string
-): Promise<number> {
-  const items = await pb
+): Promise<{ count: number; ordered: number; received: number }> {
+  type ItemShape = {
+    quantity?: number;
+    quantity_received?: number;
+    cost_price?: number;
+  };
+  const items = (await pb
     .collection(STOCK_PURCHASE_ITEMS)
-    .getFullList({ filter: `purchase = "${purchaseId}"` });
-  return items.length;
+    .getFullList({ filter: `purchase = "${purchaseId}"` })) as unknown as ItemShape[];
+  let ordered = 0;
+  let received = 0;
+  for (const item of items) {
+    const qty = Number(item.quantity ?? 0);
+    const recv = Number(item.quantity_received ?? 0);
+    const cost = Number(item.cost_price ?? 0);
+    ordered += qty * cost;
+    received += recv * cost;
+  }
+  return {
+    count: items.length,
+    ordered: Number(ordered.toFixed(2)),
+    received: Number(received.toFixed(2)),
+  };
 }
 
 /**