Fix currency synchronization and add real-time validation

src/controllers/api/purchaseController.ts

@@ -6,12 +6,28 @@ import { getInventory } from "../../services/inventoryService.ts";
 import { sendWsBroadcastTo } from "../../services/wsService.ts";
 
 export const purchaseController: RequestHandler = async (req, res) => {
-    const purchaseRequest = JSON.parse(String(req.body)) as IPurchaseRequest;
-    const accountId = await getAccountIdForRequest(req);
-    const inventory = await getInventory(accountId);
-    const response = await handlePurchase(purchaseRequest, inventory);
-    await inventory.save();
-    //console.log(JSON.stringify(response, null, 2));
-    res.json(response);
-    sendWsBroadcastTo(accountId, { update_inventory: true });
+    try {
+        const purchaseRequest = JSON.parse(String(req.body)) as IPurchaseRequest;
+        const accountId = await getAccountIdForRequest(req);
+        const inventory = await getInventory(accountId);
+        
+        const response = await handlePurchase(purchaseRequest, inventory);
+        await inventory.save();
+        
+        res.json(response);
+        sendWsBroadcastTo(accountId, { update_inventory: true });
+    } catch (error) {
+        if (error instanceof Error && error.message.includes('Insufficient')) {
+            res.status(400).json({
+                error: 'INSUFFICIENT_CURRENCY',
+                message: error.message
+            });
+        } else {
+            console.error('Purchase failed:', error);
+            res.status(500).json({
+                error: 'PURCHASE_FAILED',
+                message: 'An error occurred during purchase'
+            });
+        }
+    }
 };

src/services/inventoryService.ts

@@ -1254,10 +1254,18 @@ export const updateCurrency = (
     inventory: TInventoryDatabaseDocument,
     price: number,
     usePremium: boolean,
-    inventoryChanges: IInventoryChanges = {}
+    inventoryChanges: IInventoryChanges = {},
+    validateBalance: boolean = false
 ): IInventoryChanges => {
     if (price != 0 && isCurrencyTracked(inventory, usePremium)) {
         if (usePremium) {
+            if (validateBalance) {
+                const totalPlatinum = inventory.PremiumCredits + inventory.PremiumCreditsFree;
+                if (totalPlatinum < price) {
+                    throw new Error(`Insufficient platinum balance. Required: ${price}, Available: ${totalPlatinum}`);
+                }
+            }
+            
             if (inventory.PremiumCreditsFree > 0) {
                 const premiumCreditsFreeDelta = Math.min(price, inventory.PremiumCreditsFree) * -1;
                 inventoryChanges.PremiumCreditsFree ??= 0;
@@ -1269,6 +1277,10 @@ export const updateCurrency = (
             inventory.PremiumCredits -= price;
             logger.debug(`currency changes `, { PremiumCredits: -price });
         } else {
+            if (validateBalance && inventory.RegularCredits < price) {
+                throw new Error(`Insufficient credits balance. Required: ${price}, Available: ${inventory.RegularCredits}`);
+            }
+            
             inventoryChanges.RegularCredits ??= 0;
             inventoryChanges.RegularCredits -= price;
             inventory.RegularCredits -= price;

src/services/purchaseService.ts

@@ -209,7 +209,8 @@ export const handlePurchase = async (
         inventory,
         purchaseRequest.PurchaseParams.ExpectedPrice,
         purchaseRequest.PurchaseParams.UsePremium,
-        prePurchaseInventoryChanges
+        prePurchaseInventoryChanges,
+        true
     );
 
     switch (purchaseRequest.PurchaseParams.Source) {