fix(cart): store whole-line basket prices and send them as end_amount

.github/workflows/live-smoke.yml

@@ -2,9 +2,13 @@ name: Live smoke (daily)
 
 # Daily smoke against real Wolt consumer-api endpoints. Detects
 # upstream contract drift before users do. The read-only surface
-# (status/account/feed/venue/cart-show) always runs; a cart round-trip
-# (add a live orderable item → CLI checkout preview → MCP checkout preview
-# → remove) runs because WOLT_SMOKE_CART=1 is set below. A sell-by-weight leg
+# (status/account/feed/venue/cart-show) always runs; a cart round-trip runs
+# because WOLT_SMOKE_CART=1 is set below. It adds two units of a live
+# orderable item and checks that the line total is count x unit price and
+# that Wolt's own basket total equals the CLI subtotal. It previews checkout
+# through the CLI, where Wolt's item subtotal must match that total, and
+# through MCP. Then it removes one unit, checks the line again and removes
+# the rest. A sell-by-weight leg
 # follows it: weighted items are priced by the selected weight rather than per
 # unit, so it asserts the basket line price, previews checkout, and confirms
 # the line refuses partial removal. An option-groups leg adds a restaurant
@@ -13,8 +17,8 @@ name: Live smoke (daily)
 # checkout, and removes one of two units, which rebuilds the remaining line.
 # The MCP steps spawn wolt-mcp over stdio for read-only venue detail/hours and
 # checkout preview, so the daily run guards the MCP surface as well as the CLI.
-# Checkout is preview-only — no real order is ever placed, and only the unit
-# added by this run is removed. No login or sync.
+# Checkout is preview-only — no real order is ever placed, and only the units
+# added by this run are removed. No login or sync.
 #
 # Required repository secret:
 #   WOLT_SMOKE_CONFIG_JSON  contents of ~/.wolt/.wolt-config.json

docs/commands.md

@@ -372,8 +372,10 @@ the library ID, `venue item` the item-level ID. `--option` accepts either, and
 the basket always stores the item-level ID, the only one the Wolt app shows as
 selected. When a dish uses one library group more than once (pick one, two or
 three toppings), the library ID is ambiguous and the error lists the
-item-level IDs to choose from. The saved line price is the dish price plus the
-selected paid option values, so `wolt cart` and `wolt checkout` agree.
+item-level IDs to choose from. The saved line price is the whole-line total,
+count x (dish price plus the selected paid option values), as the Wolt app
+stores it, so `wolt cart`, `wolt checkout` and the Wolt app show the same
+total.
 
 Wolt's basket responses list selected option values without their prices.
 `cart add`, `cart remove` and `checkout` send every line back, so they take the

docs/output-contract.md

@@ -475,6 +475,13 @@ lines[]: {
 subtotal, fees, total
 ```
 
+`line_total` is the price Wolt stores for the whole line: count x (unit price
+plus paid option values). `price` is one unit of it. For a weighted line both
+are the price of the weighed amount. `subtotal` is the sum of the line totals,
+the same item total the Wolt app shows. A line whose stored price does not
+divide evenly by its count gets a `null` unit price and a warning; remove the
+item and add it again.
+
 ### `wolt cart add|remove|clear` — CartMutationResult
 
 ```

internal/cli/cart_checkout_contract_test.go

@@ -77,6 +77,8 @@ func syntheticVenuePayload() map[string]any {
 	}
 }
 
+// configuredRegressionLine builds a basket line whose price is the whole-line
+// total, as Wolt stores it.
 func configuredRegressionLine(itemID, name string, count, price int) map[string]any {
 	return map[string]any{
 		"id":    itemID,
@@ -276,18 +278,47 @@ func TestCartAddSendsWeightedBasketPayload(t *testing.T) {
 	}
 }
 
-func TestBasketLineConfiguredTotalUsesWeightedPriceAsLineTotal(t *testing.T) {
-	total, err := basketLineConfiguredTotal(map[string]any{
-		"count": 2,
-		"price": 1600,
-		"weighted_item_info": map[string]any{
-			"count":                     2,
-			"purchased_weight_in_grams": 400,
-			"weighted_item_input_type":  "number_of_items",
+func TestBasketItemsSubtotalSumsWholeLinePrices(t *testing.T) {
+	items := []any{
+		map[string]any{"count": 2, "price": 700},
+		map[string]any{
+			"count": 2,
+			"price": 3080,
+			"options": []any{map[string]any{
+				"id":     "refills",
+				"values": []any{map[string]any{"id": "yogurt", "count": 1, "price": 100}},
+			}},
 		},
+		map[string]any{
+			"count": 2,
+			"price": 1600,
+			"weighted_item_info": map[string]any{
+				"count":                     2,
+				"purchased_weight_in_grams": 400,
+			},
+		},
+	}
+	total, err := basketItemsSubtotal(items)
+	if err != nil || total != 5380 {
+		t.Fatalf("basket subtotal = %d, %v; want 5380", total, err)
+	}
+}
+
+func TestBasketLineUnitPriceSplitsCountBasedLinesOnly(t *testing.T) {
+	unit, err := basketLineUnitPrice(map[string]any{"count": 2, "price": 3080})
+	if err != nil || unit != 1540 {
+		t.Fatalf("count-based unit price = %d, %v; want 1540", unit, err)
+	}
+	unit, err = basketLineUnitPrice(map[string]any{
+		"count":              2,
+		"price":              1601,
+		"weighted_item_info": map[string]any{"count": 2, "purchased_weight_in_grams": 400},
 	})
-	if err != nil || total != 1600 {
-		t.Fatalf("weighted configured total = %d, %v; want 1600", total, err)
+	if err != nil || unit != 1601 {
+		t.Fatalf("weighted unit price = %d, %v; want the line price 1601", unit, err)
+	}
+	if _, err := basketLineUnitPrice(map[string]any{"count": 2, "price": 625}); err == nil {
+		t.Fatal("expected an error for a line price that is not a multiple of its count")
 	}
 }
 
@@ -396,7 +427,7 @@ func TestCartAddKeepsFallbackCountsConfiguredTotalAndNestedPrices(t *testing.T)
 				"venue_slug": regressionVenueSlug,
 				"currency":   "EUR",
 				"items": []any{
-					configuredRegressionLine(regressionOtherID, "Existing configured item", 2, 300),
+					configuredRegressionLine(regressionOtherID, "Existing configured item", 2, 800),
 				},
 			},
 			unrelatedRegressionBasket("000000000000000000000299"),
@@ -502,8 +533,8 @@ func TestCartAddKeepsFallbackCountsConfiguredTotalAndNestedPrices(t *testing.T)
 		asInt(added["price"]) != 700 {
 		t.Fatalf("fresh line metadata = %#v", added)
 	}
-	// The saved line price is the base price (500) plus the selected paid option
-	// values (2 x 100), so the cart and checkout preview agree.
+	// The saved line price is the whole-line total: one unit of the base price
+	// (500) plus the selected paid option values (2 x 100).
 	option := asMap(asSlice(added["options"])[0])
 	value := asMap(asSlice(option["values"])[0])
 	if asInt(value["price"]) != 100 || asInt(value["count"]) != 2 {
@@ -517,8 +548,8 @@ func TestCartAddKeepsFallbackCountsConfiguredTotalAndNestedPrices(t *testing.T)
 	if asInt(data["total_items"]) != 6 {
 		t.Fatalf("fallback total_items = %v, want 6", data["total_items"])
 	}
-	if got := asInt(asMap(data["total"])["amount"]); got != 1700 {
-		t.Fatalf("fallback total = %d, want configured target-basket total 1700 (fresh line 700 incl. options)", got)
+	if got := asInt(asMap(data["total"])["amount"]); got != 1500 {
+		t.Fatalf("fallback total = %d, want target-basket total 1500 (existing line 800 + fresh line 700 incl. options)", got)
 	}
 }
 
@@ -627,10 +658,10 @@ func TestCartRemoveKeepsFallbackCountsAndConfiguredTotalOnEmptyRefresh(t *testin
 						"id":      regressionItemID,
 						"name":    "Removed item",
 						"count":   2,
-						"price":   map[string]any{"amount": 500},
+						"price":   map[string]any{"amount": 1000},
 						"options": []any{},
 					},
-					configuredRegressionLine(regressionOtherID, "Configured remainder", 2, 300),
+					configuredRegressionLine(regressionOtherID, "Configured remainder", 2, 800),
 				},
 			},
 			unrelatedRegressionBasket("000000000000000000000299"),
@@ -682,8 +713,12 @@ func TestCartRemoveKeepsFallbackCountsAndConfiguredTotalOnEmptyRefresh(t *testin
 	if asInt(data["total_items"]) != 6 {
 		t.Fatalf("fallback total_items = %v, want 6", data["total_items"])
 	}
+	remaining := asMap(asSlice(mutation["items"])[0])
+	if asInt(remaining["count"]) != 1 || asInt(remaining["price"]) != 500 {
+		t.Fatalf("partially removed line = %#v, want count 1 at line price 500", remaining)
+	}
 	if got := asInt(asMap(data["total"])["amount"]); got != 1300 {
-		t.Fatalf("fallback total = %d, want 1300", got)
+		t.Fatalf("fallback total = %d, want 1300 (500 + 800)", got)
 	}
 }
 

internal/cli/cart_state_contract_test.go

@@ -43,7 +43,7 @@ func TestBuildCartStateNormalizesMissingCountAndHonorsExplicitZeroTotal(t *testi
 					map[string]any{
 						"id":    "item-1",
 						"name":  "Example item",
-						"price": 500,
+						"price": 600,
 						"options": []any{
 							map[string]any{
 								"id": "extra",
@@ -64,7 +64,7 @@ func TestBuildCartStateNormalizesMissingCountAndHonorsExplicitZeroTotal(t *testi
 		t.Fatalf("missing basket count was not normalized: %#v", state)
 	}
 	if got := asInt(asMap(state["subtotal"])["amount"]); got != 600 {
-		t.Fatalf("configured subtotal = %d, want 600", got)
+		t.Fatalf("subtotal = %d, want the line price 600 (paid options included)", got)
 	}
 	total := asMap(state["total"])
 	if asInt(total["amount"]) != 0 || asString(total["formatted_amount"]) != "€0.00" {

internal/cli/commands_cart.go

@@ -563,11 +563,24 @@ func newCartAddCommand(deps Dependencies) *cobra.Command {
 					warnings,
 				)
 			}
-			// Wolt stores the unit price of a basket line including its paid option
-			// values (the app does the same). Weighted lines are priced by weight.
+			// A basket line's price is the whole-line total: count x (unit price
+			// plus paid option values), as the Wolt app stores it. Weighted lines
+			// are priced by weight.
 			linePrice := price
 			if _, weighted := payloadutil.WeightConfigFromItem(itemPayload); !weighted {
-				linePrice += basketOptionsTotal(options)
+				var ok bool
+				linePrice, ok = payloadutil.CheckedMultiplyInt(price+basketOptionsTotal(options), count)
+				if !ok {
+					return emitError(
+						cmd,
+						format,
+						profile,
+						flags.Locale,
+						flags.Output,
+						"WOLT_INVALID_ARGUMENT",
+						"Item total exceeds the supported integer range; the item was not added.",
+					)
+				}
 			}
 			newLineItem := map[string]any{
 				"id":      itemID,
@@ -1417,12 +1430,8 @@ func buildCartState(page map[string]any, venueID string) (map[string]any, []stri
 			continue
 		}
 		count := basketLineCount(item)
-		price := payloadutil.MinorAmount(item["price"])
-		lineAmount, totalErr := basketLineConfiguredTotal(item)
-		if totalErr != nil {
-			totalsValid = false
-			lineAmount = 0
-		} else if nextSubtotal, ok := payloadutil.CheckedAddInt(subtotalAmount, lineAmount); ok {
+		lineAmount := payloadutil.MinorAmount(item["price"])
+		if nextSubtotal, ok := payloadutil.CheckedAddInt(subtotalAmount, lineAmount); ok {
 			subtotalAmount = nextSubtotal
 		} else {
 			totalsValid = false
@@ -1433,6 +1442,13 @@ func buildCartState(page map[string]any, venueID string) (map[string]any, []stri
 		if !totalsValid {
 			lineTotalDisplay = nil
 		}
+		price, unitErr := basketLineUnitPrice(item)
+		priceDisplay := any(formatMinorAmount(price, currency))
+		if unitErr != nil {
+			price = 0
+			priceDisplay = nil
+			warnings = append(warnings, fmt.Sprintf("basket item %q: %v", asString(item["id"]), unitErr))
+		}
 		lines = append(lines, map[string]any{
 			"line_id": asString(item["id"]),
 			"item_id": asString(item["id"]),
@@ -1441,7 +1457,7 @@ func buildCartState(page map[string]any, venueID string) (map[string]any, []stri
 			"options": coalesceAny(item["options"], []any{}),
 			"price": map[string]any{
 				"amount":           price,
-				"formatted_amount": formatMinorAmount(price, currency),
+				"formatted_amount": priceDisplay,
 			},
 			"line_total": map[string]any{
 				"amount":           lineAmount,
@@ -1536,54 +1552,29 @@ func basketLineCount(item map[string]any) int {
 	return count
 }
 
+// basketItemsSubtotal sums the line prices. Each line price is already the
+// whole-line total with paid option values included.
 func basketItemsSubtotal(items []any) (int, error) {
 	total := 0
 	for _, rawItem := range items {
-		lineTotal, err := basketLineConfiguredTotal(asMap(rawItem))
-		if err != nil {
-			return 0, err
-		}
 		var ok bool
-		total, ok = payloadutil.CheckedAddInt(total, lineTotal)
+		total, ok = payloadutil.CheckedAddInt(total, payloadutil.MinorAmount(asMap(rawItem)["price"]))
 		if !ok {
 			return 0, fmt.Errorf("basket subtotal exceeds the supported integer range")
 		}
 	}
 	return total, nil
 }
 
-func basketLineConfiguredTotal(item map[string]any) (int, error) {
-	count := basketLineCount(item)
+// basketLineUnitPrice is the price of one unit of a count-based line. A
+// weighted line has no per-unit price in the basket, so its line price is
+// returned as is.
+func basketLineUnitPrice(item map[string]any) (int, error) {
+	price := payloadutil.MinorAmount(item["price"])
 	if asMap(item["weighted_item_info"]) != nil {
-		count = 1
-	}
-	unitAmount := payloadutil.MinorAmount(item["price"])
-	for _, rawOption := range asSlice(item["options"]) {
-		option := asMap(rawOption)
-		for _, rawValue := range asSlice(option["values"]) {
-			value := asMap(rawValue)
-			valueCount := asInt(value["count"])
-			if valueCount <= 0 {
-				valueCount = 1
-			}
-			optionAmount, ok := payloadutil.CheckedMultiplyInt(
-				payloadutil.MinorAmount(value["price"]),
-				valueCount,
-			)
-			if !ok {
-				return 0, fmt.Errorf("basket option total exceeds the supported integer range")
-			}
-			unitAmount, ok = payloadutil.CheckedAddInt(unitAmount, optionAmount)
-			if !ok {
-				return 0, fmt.Errorf("basket item unit total exceeds the supported integer range")
-			}
-		}
-	}
-	lineTotal, ok := payloadutil.CheckedMultiplyInt(unitAmount, count)
-	if !ok {
-		return 0, fmt.Errorf("basket item total exceeds the supported integer range")
+		return price, nil
 	}
-	return lineTotal, nil
+	return payloadutil.LineUnitPrice(price, basketLineCount(item))
 }
 
 func buildCartTable(data map[string]any, includeDetails bool) string {

internal/mcpserver/cart_checkout_contract_test.go

@@ -602,8 +602,10 @@ func TestCheckoutPayloadPreservesNestedBasketPricesThroughHandler(t *testing.T)
 	}
 	plan := asMap(captured["purchase_plan"])
 	item := asMap(asSlice(plan["menu_items"])[0])
-	if asInt(item["base_price"]) != 650 {
-		t.Fatalf("base_price = %v, want 650", item["base_price"])
+	// base_price is one unit without the paid option value; end_amount is the
+	// whole-line price with it.
+	if asInt(item["base_price"]) != 550 || asInt(item["end_amount"]) != 650 {
+		t.Fatalf("base_price, end_amount = %v, %v; want 550, 650", item["base_price"], item["end_amount"])
 	}
 	option := asMap(asSlice(item["options"])[0])
 	value := asMap(asSlice(option["values"])[0])

internal/mcpserver/tools_cart.go

@@ -280,11 +280,17 @@ func (tc *ToolCtx) handleCartAdd(ctx context.Context, _ *mcp.CallToolRequest, in
 	}
 	orderAvailability, availabilityWarnings := tc.cartVenueAvailability(ctx, ref, loc)
 
+	// A basket line's price is the whole-line total, as the Wolt app stores
+	// it. Weighted lines are repriced by weight when they are built.
+	linePrice, ok := payloadutil.CheckedMultiplyInt(price, count)
+	if !ok {
+		return nil, CartAddOutput{}, toolErrf("item was NOT added because its total exceeds the supported integer range")
+	}
 	newLine := map[string]any{
 		"id":      in.ItemID,
 		"count":   count,
 		"name":    name,
-		"price":   price,
+		"price":   linePrice,
 		"options": []any{},
 		"substitution_settings": map[string]any{
 			"is_allowed": in.AllowSubstitutions,