orders

services/productVisibility.go

@@ -51,3 +51,37 @@ func InStockOnly(products []models.Products, locationID int) []models.Products {
 	}
 	return inStock
 }
+
+// InStockOnlyGrouped is InStockOnly for the grouped shape `getallproducts`
+// returns: a tenant with its products, rather than a flat list.
+//
+// ── Why this one does NOT skip when locationID is 0 ──────────────────────────
+//
+// InStockOnly above returns early without an outlet, because the query behind
+// it computes stock scoped to that outlet and answers 0 for everything when
+// there is none — filtering that would empty the catalogue rather than filter
+// it. FetchFilteredProducts is built differently: its stock subquery reads
+// `(? = 0 OR locationid = ?)`, so with no outlet it aggregates the ledger across
+// the tenant's outlets and still returns a real number. Measured 2026-09-02 on
+// R mart: 24 products unscoped, 20 with a live balance and 4 at zero.
+//
+// So the number is trustworthy either way, and the rule can be applied either
+// way: a shop that holds none of something anywhere is not offering it.
+//
+// A tenant left with no sellable products keeps its group, with an empty list.
+// Dropping the group would tell the app the shop does not exist, which is a
+// different and wrong statement — the shop is open, it has nothing on the shelf.
+func InStockOnlyGrouped(groups []models.Tenantproducts) []models.Tenantproducts {
+	out := make([]models.Tenantproducts, 0, len(groups))
+	for _, group := range groups {
+		kept := make([]models.Products, 0, len(group.Products))
+		for _, product := range group.Products {
+			if product.Productstock > 0 {
+				kept = append(kept, product)
+			}
+		}
+		group.Products = kept
+		out = append(out, group)
+	}
+	return out
+}

services/productVisibility_test.go

@@ -606,3 +606,64 @@ func TestImportPublishesAfterTheRowsExist(t *testing.T) {
 		t.Fatalf("want CreateProductLocation before PublishPricedLocations, got %v", repo.calls)
 	}
 }
+
+/*
+The grouped shape, which is what `getallproducts` answers with.
+
+Measured 2026-09-02 on R mart: the app was offering four products with a zero
+balance — Cadbury Bournvita 500g, Amul 90g, Amul 150g and a Dabur chewing gum.
+A shopper could pick any of them and only find out at checkout, where the stock
+check answers 409.
+*/
+
+func groupOf(stocks ...int) []models.Tenantproducts {
+	products := make([]models.Products, 0, len(stocks))
+	for i, s := range stocks {
+		products = append(products, models.Products{Productid: 100 + i, Productstock: s})
+	}
+	return []models.Tenantproducts{{Products: products}}
+}
+
+func TestAnEmptyShelfIsNotOfferedToShoppers(t *testing.T) {
+	got := InStockOnlyGrouped(groupOf(5, 0, 3, 0))
+	if len(got) != 1 {
+		t.Fatalf("expected the tenant group to survive, got %d groups", len(got))
+	}
+	if len(got[0].Products) != 2 {
+		t.Fatalf("expected 2 sellable products, got %d", len(got[0].Products))
+	}
+	for _, p := range got[0].Products {
+		if p.Productstock <= 0 {
+			t.Errorf("product %d has no stock and was still offered", p.Productid)
+		}
+	}
+}
+
+func TestAShopWithNothingOnTheShelfStillExists(t *testing.T) {
+	// The group is kept with an empty list. Dropping it would tell the app the
+	// shop is not there, which is a different and wrong statement: it is open,
+	// it just has nothing to sell today.
+	got := InStockOnlyGrouped(groupOf(0, 0))
+	if len(got) != 1 {
+		t.Fatalf("the shop disappeared: got %d groups", len(got))
+	}
+	if len(got[0].Products) != 0 {
+		t.Errorf("expected nothing sellable, got %d", len(got[0].Products))
+	}
+}
+
+func TestANegativeBalanceIsNotStockWhenGrouped(t *testing.T) {
+	// A ledger can go negative through correction. Negative is not "some".
+	got := InStockOnlyGrouped(groupOf(-4))
+	if len(got[0].Products) != 0 {
+		t.Errorf("a negative balance was treated as stock")
+	}
+}
+
+func TestFilteringGroupsDoesNotDisturbTheCallersSlice(t *testing.T) {
+	original := groupOf(1, 0)
+	_ = InStockOnlyGrouped(original)
+	if len(original[0].Products) != 2 {
+		t.Errorf("the caller's slice was modified: %d products left", len(original[0].Products))
+	}
+}