fix: keep map buy flow moving after refresh failure

frontend/src/pages/LocationMapManager.jsx

@@ -42,6 +42,15 @@ function getNextMapBuyItem(items, currentIndex, excludedItemId) {
   return remainingItems[Math.min(Math.max(currentIndex, 0), remainingItems.length - 1)];
 }
 
+function getLocallyReducedMapItem(item, quantity) {
+  const currentQuantity = Number(item.quantity || 1);
+  const boughtQuantity = Math.max(1, Number(quantity || 1));
+  return {
+    ...item,
+    quantity: Math.max(1, currentQuantity - boughtQuantity),
+  };
+}
+
 export default function LocationMapManager() {
   const { storeId, locationId } = useParams();
   const navigate = useNavigate();
@@ -183,11 +192,14 @@ export default function LocationMapManager() {
         nextBuyModalItems = buyModalItems.filter((candidate) => candidate.id !== item.id);
         updateMapItems((currentItems) => currentItems.filter((candidate) => candidate.id !== item.id));
       } else {
-        const response = await getItemByName(activeHousehold.id, locationId, item.item_name);
+        let updatedItem;
-        const updatedItem = response.data || {
+        try {
-          ...item,
+          const response = await getItemByName(activeHousehold.id, locationId, item.item_name);
-          quantity: Math.max(1, Number(item.quantity || 1) - Number(quantity || 1)),
+          updatedItem = response.data || getLocallyReducedMapItem(item, quantity);
-        };
+        } catch {
+          updatedItem = getLocallyReducedMapItem(item, quantity);
+          toast.info("Updated item locally", "Latest quantity will sync when the map reloads.");
+        }
         nextBuyModalItems = buyModalItems.map((candidate) => (candidate.id === item.id ? updatedItem : candidate));
 
         updateMapItems((currentItems) =>

frontend/tests/location-map-manager.spec.ts

@@ -2445,6 +2445,100 @@ test("viewer advances map buy modal after partial quantity buys", async ({ page
   await expect(page.getByRole("button", { name: "Mark flour bought" }).locator("small")).toHaveText("x2");
 });
 
+test("viewer keeps map buy flow moving when quantity refresh fails", async ({ page }) => {
+  await mockMapShell(page);
+
+  const partialItems = [
+    {
+      id: 4311,
+      item_name: "flour",
+      quantity: 3,
+      bought: false,
+      zone_id: 501,
+      zone: "Bakery",
+      added_by_users: ["map-user"],
+    },
+    {
+      id: 4312,
+      item_name: "yeast",
+      quantity: 1,
+      bought: false,
+      zone_id: 501,
+      zone: "Bakery",
+      added_by_users: ["map-user"],
+    },
+  ];
+  const mapState = {
+    ...publishedMapState([
+      {
+        id: 1535,
+        location_map_id: 901,
+        zone_id: 501,
+        zone_name: "Bakery",
+        type: "zone",
+        label: "Bakery",
+        x: 40,
+        y: 40,
+        width: 260,
+        height: 160,
+        rotation: 0,
+        locked: false,
+        visible: true,
+        sort_order: 1,
+      },
+    ], true),
+    items: partialItems,
+  };
+  const boughtPayloads: Array<Record<string, unknown>> = [];
+
+  await page.route("**/households/1/locations/10/map", async (route) => {
+    await route.fulfill({
+      status: 200,
+      contentType: "application/json",
+      body: JSON.stringify(mapState),
+    });
+  });
+
+  await page.route("**/households/1/locations/10/list/item**", async (route) => {
+    if (route.request().method() === "GET") {
+      await route.fulfill({
+        status: 503,
+        contentType: "application/json",
+        body: JSON.stringify({ error: "refresh unavailable" }),
+      });
+      return;
+    }
+
+    boughtPayloads.push(await route.request().postDataJSON());
+    await route.fulfill({
+      status: 200,
+      contentType: "application/json",
+      body: JSON.stringify({ success: true }),
+    });
+  });
+
+  await page.goto("/stores/100/locations/10/map");
+  await page.locator('[data-object-key="1535"]').locator("rect").first().click();
+  await page.getByRole("button", { name: "Mark flour bought" }).click();
+  await expect(page.locator(".confirm-buy-item-name")).toHaveText("flour");
+
+  await page.locator(".confirm-buy-counter-btn").first().click();
+  await page.locator(".confirm-buy-counter-btn").first().click();
+  await expect(page.locator(".confirm-buy-counter-display")).toHaveValue("1");
+  await page.getByRole("button", { name: "Mark as Bought" }).click();
+
+  await expect.poll(() => boughtPayloads.length).toBe(1);
+  expect(boughtPayloads[0]).toMatchObject({
+    item_name: "flour",
+    bought: true,
+    quantity_bought: 1,
+  });
+  await expect(page.getByText("Updated item locally")).toBeVisible();
+  await expect(page.locator(".confirm-buy-item-name")).toHaveText("yeast");
+  await expect(page.getByRole("button", { name: "Mark flour bought" }).locator("small")).toHaveText("x2");
+  await expect(page.getByText("Mark item bought failed")).toHaveCount(0);
+});
+
 test("viewer shows completed zone items without rebuy actions", async ({ page }) => {
   await mockMapShell(page);