Add check for insufficient funds

src/screens/WalletEmbed.tsx

@@ -76,6 +76,13 @@ export const WalletEmbed = () => {
     source?.postMessage({ type, data }, origin);
   };
 
+  const checkSufficientFunds = (amount: string, balance: string) => {
+    const amountBigNum = BigNumber.from(String(amount));
+    const balanceBigNum = BigNumber.from(balance);
+
+    return balanceBigNum.gt(amountBigNum);
+  };
+
   useEffect(() => {
     const handleGetAccounts = async (event: MessageEvent) => {
       if (event.data.type !== 'REQUEST_WALLET_ACCOUNTS') return;
@@ -172,16 +179,6 @@ export const WalletEmbed = () => {
           },
         };
 
-        const gasEstimation = await client.simulate(fromAddress, [sendMsg], MEMO);
-        const gasLimit = String(
-          Math.round(gasEstimation * Number(process.env.REACT_APP_GAS_ADJUSTMENT))
-        );
-        setGasLimit(gasLimit);
-
-        const gasPrice = GasPrice.fromString(`${network.gasPrice}${network.nativeDenom}`);
-        const cosmosFees = calculateFee(Number(gasLimit), gasPrice);
-        setFees(cosmosFees.amount[0].amount);
-
         setTransactionDetails({
           chainId,
           fromAddress,
@@ -192,6 +189,21 @@ export const WalletEmbed = () => {
           requestedNetwork: network,
         });
 
+        if (!checkSufficientFunds(amount, balance.amount)) {
+          console.log("Insufficient funds detected. Throwing error.");
+          throw new Error('Insufficient funds');
+        }
+
+        const gasEstimation = await client.simulate(fromAddress, [sendMsg], MEMO);
+        const gasLimit = String(
+          Math.round(gasEstimation * Number(process.env.REACT_APP_GAS_ADJUSTMENT))
+        );
+        setGasLimit(gasLimit);
+
+        const gasPrice = GasPrice.fromString(`${network.gasPrice}${network.nativeDenom}`);
+        const cosmosFees = calculateFee(Number(gasLimit), gasPrice);
+        setFees(cosmosFees.amount[0].amount);
+
         setIsTxRequested(true);
       } catch (error) {
         if (!(error instanceof Error)) {
@@ -346,7 +358,8 @@ export const WalletEmbed = () => {
         hideDialog={() => {
           setTxError(null)
           if (window.parent) {
-            window.parent.postMessage('closeIframe', '*');
+            sendMessage(window.parent, 'TRANSACTION_RESPONSE', null, '*');
+            sendMessage(window.parent, 'closeIframe', null, '*');
           }
         }}
       />