From d01b6675b44daa52ff99a18b17275e597fb786eb Mon Sep 17 00:00:00 2001
From: matst80 <mats.tornberg@gmail.com>
Date: Sun, 10 Nov 2024 22:54:56 +0100
Subject: [PATCH] quantity

---
 cart-grain.go | 52 +++++++++++++++++++++++++++++++++------------------
 1 file changed, 34 insertions(+), 18 deletions(-)

diff --git a/cart-grain.go b/cart-grain.go
index 9473581..34a19fd 100644
--- a/cart-grain.go
+++ b/cart-grain.go
@@ -25,11 +25,12 @@ func (id *CartId) UnmarshalJSON(data []byte) error {
 }
 
 type CartItem struct {
-	Id    int    `json:"id"`
-	Sku   string `json:"sku"`
-	Name  string `json:"name"`
-	Price int64  `json:"price"`
-	Image string `json:"image"`
+	Id       int    `json:"id"`
+	Sku      string `json:"sku"`
+	Name     string `json:"name"`
+	Price    int64  `json:"price"`
+	Quantity int    `json:"qty"`
+	Image    string `json:"image"`
 }
 
 type CartDelivery struct {
@@ -64,7 +65,7 @@ func (c *CartGrain) GetLastChange() int64 {
 	return *c.storageMessages[len(c.storageMessages)-1].TimeStamp
 }
 
-func getItemData(sku string) (*messages.AddItem, error) {
+func getItemData(sku string, qty int) (*messages.AddItem, error) {
 	item, err := FetchItem(sku)
 	if err != nil {
 		return nil, err
@@ -87,7 +88,7 @@ func getItemData(sku string) (*messages.AddItem, error) {
 	}
 
 	return &messages.AddItem{
-		Quantity: 1,
+		Quantity: int32(qty),
 		Price:    int64(price),
 		Sku:      sku,
 		Name:     item.Title,
@@ -95,8 +96,8 @@ func getItemData(sku string) (*messages.AddItem, error) {
 	}, nil
 }
 
-func (c *CartGrain) AddItem(sku string) ([]byte, error) {
-	cartItem, err := getItemData(sku)
+func (c *CartGrain) AddItem(sku string, qty int) ([]byte, error) {
+	cartItem, err := getItemData(sku, qty)
 	if err != nil {
 		return nil, err
 	}
@@ -130,21 +131,36 @@ func (c *CartGrain) HandleMessage(message *Message, isReplay bool) ([]byte, erro
 		if !ok {
 			err = fmt.Errorf("expected AddRequest")
 		} else {
-			return c.AddItem(msg.Sku)
+			return c.AddItem(msg.Sku, 1) // extent AddRequest to include quantity
 		}
 	case AddItemType:
 		msg, ok := message.Content.(*messages.AddItem)
 		if !ok {
 			err = fmt.Errorf("expected AddItem")
 		} else {
-			c.lastItemId++
-			c.Items = append(c.Items, CartItem{
-				Id:    c.lastItemId,
-				Sku:   msg.Sku,
-				Name:  msg.Name,
-				Price: msg.Price,
-				Image: msg.Image,
-			})
+			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 {
+				c.lastItemId++
+				c.Items = append(c.Items, CartItem{
+					Id: c.lastItemId,
+
+					Sku:   msg.Sku,
+					Name:  msg.Name,
+					Price: msg.Price,
+					Image: msg.Image,
+				})
+			}
 			c.TotalPrice += msg.Price * int64(msg.Quantity)
 		}
 	case RemoveItemType: