Add Open Food Facts barcode lookup workflow

src/modules/openFoodFacts.ts

@@ -0,0 +1,53 @@
+export interface ExternalProductInfo {
+  name: string | null;
+  brand?: string | null;
+  quantity?: string | null;
+  image?: string | null;
+  source: 'openfoodfacts';
+}
+
+const BASE_URL = 'https://world.openfoodfacts.org/api/v2/product';
+const REQUEST_TIMEOUT_MS = 5000;
+
+const isOffline = () => typeof navigator !== 'undefined' && 'onLine' in navigator && !navigator.onLine;
+
+export const fetchProductFromOFF = async (barcode: string): Promise<ExternalProductInfo | null> => {
+  if (!barcode || isOffline()) {
+    return null;
+  }
+
+  const controller = new AbortController();
+  const timeout = setTimeout(() => controller.abort(), REQUEST_TIMEOUT_MS);
+
+  try {
+    const response = await fetch(`${BASE_URL}/${barcode}.json`, { signal: controller.signal });
+    if (!response.ok) return null;
+
+    const data = (await response.json()) as {
+      status?: number;
+      product?: {
+        product_name?: string | null;
+        brands?: string | null;
+        quantity?: string | null;
+        image_url?: string | null;
+      };
+    };
+
+    if (data?.status !== 1 || !data.product || !data.product.product_name) {
+      return null;
+    }
+
+    return {
+      name: data.product.product_name ?? null,
+      brand: data.product.brands ?? null,
+      quantity: data.product.quantity ?? null,
+      image: data.product.image_url ?? null,
+      source: 'openfoodfacts',
+    } satisfies ExternalProductInfo;
+  } catch (error) {
+    return null;
+  } finally {
+    clearTimeout(timeout);
+  }
+};
+