Add missing purchase item

Assets/PerfectWorld/Scripts/Managers/EC_Inventory.cs

@@ -129,6 +129,42 @@ namespace BrewMonster.Scripts.Managers
             m_aItems[iSlot2] = tmp;
         }
 
+        /// <summary>
+        /// Place or stack item in a specific slot (server-specified slot). Matches C++ expectation that client uses same slot as server.
+        /// </summary>
+        public bool PutItemInSlot(int iSlot, int tid, int iExpireDate, int iAmount, out int piLastSlot, out int piLastAmount)
+        {
+            piLastSlot = -1;
+            piLastAmount = 0;
+            if (iSlot < 0 || iSlot >= m_aItems.Length || iAmount <= 0)
+                return false;
+
+            var slotItem = m_aItems[iSlot];
+            if (slotItem == null)
+            {
+                var newItem = EC_IvtrItem.CreateItem(tid, iExpireDate, iAmount);
+                if (newItem == null)
+                    return false;
+                newItem.Slot = iSlot;
+                newItem.SetCount(iAmount);
+                m_aItems[iSlot] = newItem;
+                piLastSlot = iSlot;
+                piLastAmount = iAmount;
+                return true;
+            }
+            if (slotItem.GetTemplateID() != tid)
+                return false;
+            int pileLimit = Math.Max(1, EC_IvtrItem.GetPileLimit(tid));
+            int canAdd = Math.Max(0, pileLimit - Math.Max(0, slotItem.GetCount()));
+            if (canAdd <= 0)
+                return false;
+            int add = Math.Min(canAdd, iAmount);
+            slotItem.AddAmount(add);
+            piLastSlot = iSlot;
+            piLastAmount = slotItem.GetCount();
+            return true;
+        }
+
         public bool MergeItem(int tid, int iExpireDate, int iAmount, out int piLastSlot, out int piLastAmount)
         {
             piLastSlot = -1;
@@ -170,6 +206,9 @@ namespace BrewMonster.Scripts.Managers
                 return false;
             }
             var newItem = EC_IvtrItem.CreateItem(tid, iExpireDate, iAmount);
+            if (newItem == null)
+                return false;
+            newItem.Slot = firstEmpty;
             newItem.SetCount(iAmount);
 
             m_aItems[firstEmpty] = newItem;

Assets/PerfectWorld/Scripts/Network/CSNetwork/GPDataType.cs

@@ -1315,6 +1315,26 @@ namespace CSNetwork.GPDataType
         public byte bySlot;
     }
 
+    /// <summary>One item in cmd_purchase_item (buy from NPC/booth). Wire: item_id, expire_date, count, inv_index, booth_slot = 15 bytes.</summary>
+    [StructLayout(LayoutKind.Sequential, Pack = 1)]
+    public struct cmd_purchase_item_ITEM
+    {
+        public int item_id;
+        public int expire_date;
+        public uint count;
+        public ushort inv_index;
+        public byte booth_slot;
+    }
+
+    /// <summary>Fixed header of cmd_purchase_item. Rest of packet is item_count x cmd_purchase_item_ITEM.</summary>
+    [StructLayout(LayoutKind.Sequential, Pack = 1)]
+    public struct cmd_purchase_item_header
+    {
+        public uint cost;
+        public uint yinpiao;
+        public byte flag;
+        public ushort item_count;
+    }
 
     [StructLayout(LayoutKind.Sequential, Pack = 1)]
     public struct cmd_get_own_money
@@ -1394,7 +1414,7 @@ namespace CSNetwork.GPDataType
         public byte index;
     };
     [StructLayout(LayoutKind.Sequential, Pack = 1)]
-    struct cmd_pickup_item
+    public struct cmd_pickup_item
     {
         public int tid;
         public int expire_date;

Assets/PerfectWorld/Scripts/UI/NPCShopDetailPanel.cs

@@ -24,6 +24,7 @@ public class NPCShopDetailPanel : MonoBehaviour
     
     private GShopItem currentItem;
     private NPCShopUIManager shopManager;
+    private int shopItemIndex;
     
     void Start()
     {
@@ -39,10 +40,11 @@ public class NPCShopDetailPanel : MonoBehaviour
             buyButton.onClick.AddListener(OnBuyButtonClicked);
     }
     
-    public void SetupDetailPanel(GShopItem item, NPCShopUIManager manager)
+    public void SetupDetailPanel(GShopItem item, NPCShopUIManager manager, int index)
     {
         currentItem = item;
         shopManager = manager;
+        shopItemIndex = index;
         
         UpdateDisplay();
     }
@@ -189,17 +191,19 @@ public class NPCShopDetailPanel : MonoBehaviour
             }
         }
 
-        // Create npc_trade_item array for buying from NPC
-        // The tid is the item template ID, index is shop item index (0 for now), count is quantity to buy
+        // Server requires SEVNPC_HELLO with NPC id before buy, and the correct shop slot index
+        if (shopManager != null && shopManager.CurrentNPCID != 0)
+            UnityGameSession.c2s_CmdNPCSevHello((int)shopManager.CurrentNPCID);
+
+        // Create npc_trade_item: tid = template ID, index = shop slot (server validates this), count = quantity
         npc_trade_item[] items = new npc_trade_item[1];
         items[0] = new npc_trade_item
         {
             tid = (int)currentItem.id,
-            index = 0, // Shop item index - may need to be determined from shop item position
-            count = 1  // Quantity to buy
+            index = (uint)shopItemIndex,
+            count = 1
         };
 
-        // Send the buy command
         UnityGameSession.c2s_CmdNPCSevBuy(1, items);
         
         Debug.Log($"[NPCShopDetailPanel] Sent buy command for item {currentItem.id}, price {price}");

Assets/PerfectWorld/Scripts/UI/NPCShopItemPanel.cs

@@ -19,6 +19,7 @@ public class NPCShopItemPanel : MonoBehaviour
     private GShopItem itemData;
     private Coroutine iconLoadCoroutine;
     private NPCShopUIManager shopManager;
+    private int shopItemIndex;
     
     void Start()
     {
@@ -54,10 +55,11 @@ public class NPCShopItemPanel : MonoBehaviour
         }
     }
     
-    public void SetupItem(GShopItem item, NPCShopUIManager manager)
+    public void SetupItem(GShopItem item, NPCShopUIManager manager, int index)
     {
         itemData = item;
         shopManager = manager;
+        shopItemIndex = index;
         UpdateDisplay();
     }
     
@@ -65,7 +67,7 @@ public class NPCShopItemPanel : MonoBehaviour
     {
         if (shopManager != null && itemData.id != 0)
         {
-            shopManager.ShowItemDetail(itemData);
+            shopManager.ShowItemDetail(itemData, shopItemIndex);
         }
     }
     

Assets/PerfectWorld/Scripts/UI/NPCShopUIManager.cs

@@ -35,6 +35,9 @@ public class NPCShopUIManager : MonoBehaviour
     private int currentTabIndex = 0;
     private uint currentNPCID = 0;
     private NPC_SELL_SERVICE? cachedSellService = null;
+
+    /// <summary>Current NPC id for this shop session. Send SEVNPC_HELLO with this before buy.</summary>
+    public uint CurrentNPCID => currentNPCID;
     private NPCShopDetailPanel detailPanelScript;
     
     void Start()
@@ -278,8 +281,9 @@ public class NPCShopUIManager : MonoBehaviour
             if (elementDataMan == null)
                 return;
             
-            foreach (var good in page.goods)
+            for (int i = 0; i < page.goods.Length; i++)
             {
+                var good = page.goods[i];
                 if (good.id == 0)
                     continue;
                 
@@ -293,8 +297,8 @@ public class NPCShopUIManager : MonoBehaviour
                 // Create GShopItem
                 GShopItem shopItem = CreateShopItemFromGood(good, itemData, itemDataType);
                 
-                // Create panel
-                CreateItemPanel(shopItem);
+                // Create panel with shop slot index (server expects this in npc_trade_item.index)
+                CreateItemPanel(shopItem, i);
             }
         }
     }
@@ -372,7 +376,7 @@ public class NPCShopUIManager : MonoBehaviour
         return shopItem;
     }
     
-    void CreateItemPanel(GShopItem item)
+    void CreateItemPanel(GShopItem item, int shopItemIndex)
     {
         if (itemPanelPrefab == null || itemContainer == null)
             return;
@@ -386,7 +390,7 @@ public class NPCShopUIManager : MonoBehaviour
         
         if (itemPanelScript != null)
         {
-            itemPanelScript.SetupItem(item, this);
+            itemPanelScript.SetupItem(item, this, shopItemIndex);
         }
         else
         {
@@ -406,7 +410,7 @@ public class NPCShopUIManager : MonoBehaviour
         currentItemPanels.Clear();
     }
     
-    public void ShowItemDetail(GShopItem item)
+    public void ShowItemDetail(GShopItem item, int shopItemIndex)
     {
         if (item.id == 0)
             return;
@@ -428,7 +432,7 @@ public class NPCShopUIManager : MonoBehaviour
         if (detailPanelScript != null)
         {
             npcShopDetailPanel.SetActive(true);
-            detailPanelScript.SetupDetailPanel(item, this);
+            detailPanelScript.SetupDetailPanel(item, this, shopItemIndex);
         }
         else
         {

Assets/Scripts/CECHostPlayer.cs

@@ -565,6 +565,9 @@ namespace BrewMonster
                 case EC_MsgDef.MSG_HST_PICKUPITEM:
                     OnMsgHstPickupItem(Msg);
                     break;
+                case EC_MsgDef.MSG_HST_PURCHASEITEMS:
+                    OnMsgHstPurchaseItems(Msg);
+                    break;
                 case EC_MsgDef.MSG_HST_PRODUCEITEM:
                     OnMsgHstProduceItem(Msg);
                     break;