shortcut quantity change

cart-grain.go

@@ -160,6 +160,17 @@ func (c *CartGrain) ItemsWithoutDelivery() []int {
 	return ret
 }
 
+func (c *CartGrain) FindItemWithSku(sku string) (*CartItem, bool) {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	for _, item := range c.Items {
+		if item.Sku == sku {
+			return item, true
+		}
+	}
+	return nil, false
+}
+
 func (c *CartGrain) HandleMessage(message *Message, isReplay bool) ([]byte, error) {
 	if message.TimeStamp == nil {
 		now := time.Now().Unix()
@@ -173,26 +184,28 @@ func (c *CartGrain) HandleMessage(message *Message, isReplay bool) ([]byte, erro
 		if !ok {
 			err = fmt.Errorf("expected AddRequest")
 		} else {
-			return c.AddItem(msg.Sku, 1) // extent AddRequest to include quantity
+			existingItem, found := c.FindItemWithSku(msg.Sku)
+			if found {
+				existingItem.Quantity += int(msg.Quantity)
+				c.TotalPrice += existingItem.Price * int64(msg.Quantity)
+			} else {
+				return c.AddItem(msg.Sku, int(msg.Quantity)) // extent AddRequest to include quantity
+			}
 		}
 	case AddItemType:
 		msg, ok := message.Content.(*messages.AddItem)
 		if !ok {
 			err = fmt.Errorf("expected AddItem")
 		} else {
-			found := false
+
 			if msg.Quantity < 1 {
 				return nil, fmt.Errorf("invalid quantity")
 			}
-			for _, item := range c.Items {
-				if item.Sku == msg.Sku {
-					found = true
-					item.Quantity += int(msg.Quantity)
-					c.TotalPrice += item.Price * int64(msg.Quantity)
-					break
-				}
-			}
-			if !found {
+			existingItem, found := c.FindItemWithSku(msg.Sku)
+			if found {
+				existingItem.Quantity += int(msg.Quantity)
+				c.TotalPrice += existingItem.Price * int64(msg.Quantity)
+			} else {
 				c.mu.Lock()
 				c.lastItemId++
 				c.Items = append(c.Items, &CartItem{

cart-grain_test.go

@@ -16,6 +16,57 @@ func GetMessage(t uint16, data interface{}) *Message {
 	}
 }
 
+func TestAddToCartShortCut(t *testing.T) {
+	grain, err := spawn(ToCartId("kalle"))
+	if err != nil {
+		t.Errorf("Error spawning: %v\n", err)
+	}
+	if len(grain.Items) != 0 {
+		t.Errorf("Expected 0 items, got %d\n", len(grain.Items))
+	}
+	msg := GetMessage(AddItemType, &messages.AddItem{
+		Quantity: 2,
+		Price:    100,
+		Sku:      "123",
+		Name:     "Test item",
+		Image:    "test.jpg",
+	})
+
+	_, err = grain.HandleMessage(msg, false)
+	if err != nil {
+		t.Errorf("Error handling message: %v\n", err)
+	}
+	if len(grain.Items) != 1 {
+		t.Errorf("Expected 1 item, got %d\n", len(grain.Items))
+	}
+	if grain.Items[0].Quantity != 2 {
+		t.Errorf("Expected quantity 2, got %d\n", grain.Items[0].Quantity)
+	}
+	if len(grain.storageMessages) != 1 {
+		t.Errorf("Expected 1 storage message, got %d\n", len(grain.storageMessages))
+	}
+	shortCutMessage := GetMessage(AddRequestType, &messages.AddRequest{
+		Quantity: 2,
+		Sku:      "123",
+	})
+	_, err = grain.HandleMessage(shortCutMessage, false)
+	if err != nil {
+		t.Errorf("Error handling message: %v\n", err)
+	}
+	if len(grain.Items) != 1 {
+		t.Errorf("Expected 1 item, got %d\n", len(grain.Items))
+	}
+	if len(grain.storageMessages) != 2 {
+		t.Errorf("Expected 2 storage message, got %d\n", len(grain.storageMessages))
+	}
+	if grain.storageMessages[0].Type != AddItemType {
+		t.Errorf("Expected AddItemType, got %d\n", grain.storageMessages[0].Type)
+	}
+	if grain.storageMessages[1].Type != AddRequestType {
+		t.Errorf("Expected AddRequestType, got %d\n", grain.storageMessages[1].Type)
+	}
+}
+
 func TestAddToCart(t *testing.T) {
 	grain, err := spawn(ToCartId("kalle"))
 	if err != nil {