Add pre-check for nablaApprove phase.

apps/api/src/api/services/moonbeam/balance.ts

@@ -25,6 +25,32 @@ export class BalanceCheckError extends Error {
   }
 }
 
+interface GetBalanceParams {
+  tokenAddress: `0x${string}`;
+  ownerAddress: `0x${string}`;
+  chain: any;
+}
+
+export async function getEvmTokenBalance({ tokenAddress, ownerAddress, chain }: GetBalanceParams): Promise<Big> {
+  try {
+    const publicClient = createPublicClient({
+      chain,
+      transport: http(),
+    });
+
+    const balanceResult = (await publicClient.readContract({
+      address: tokenAddress,
+      abi: erc20ABI,
+      functionName: 'balanceOf',
+      args: [ownerAddress],
+    })) as string;
+
+    return new Big(balanceResult);
+  } catch (err: any) {
+    throw new Error(`Failed to read token balance: ${err.message ?? err}`);
+  }
+}
+
 export function checkEvmBalancePeriodically(
   tokenAddress: string,
   brlaEvmAddress: string,

apps/api/src/api/services/phases/handlers/nabla-approve-handler.ts

@@ -1,6 +1,8 @@
 import { RampPhase, decodeSubmittableExtrinsic } from '@packages/shared';
+import { NABLA_ROUTER } from '@packages/shared';
 import { ExecuteMessageResult, createExecuteMessageExtrinsic, submitExtrinsic } from '@pendulum-chain/api-solang';
 import { Abi } from '@polkadot/api-contract';
+import Big from 'big.js';
 import logger from '../../../../config/logger';
 import { erc20WrapperAbi } from '../../../../contracts/ERC20Wrapper';
 import RampState from '../../../../models/rampState.model';
@@ -17,6 +19,25 @@ export class NablaApprovePhaseHandler extends BasePhaseHandler {
     const networkName = 'pendulum';
     const pendulumNode = await apiManager.getApi(networkName);
 
+    // Pre check: check if the approve has already been performed.
+    try {
+      const approval = await pendulumNode.api.query.tokenAllowance.approvals(
+        state.state.inputTokenPendulumDetails,
+        state.state.pendulumEphemeralAddress,
+        NABLA_ROUTER,
+      );
+      const requiredAmount = new Big(state.state.inputAmountBeforeSwapRaw);
+      const approvedAmount = approval.toString() !== '' ? Big(approval.toString()) : Big(0);
+      if (approvedAmount.gte(requiredAmount)) {
+        logger.info(`NablaApprovePhaseHandler: Amount already approved. Skipping approval.`);
+        return this.transitionToNextPhase(state, 'nablaSwap');
+      }
+    } catch (e) {
+      throw this.createRecoverableError(
+        `NablaApprovePhaseHandler: Could not check if the approve has already been performed. ${(e as Error).message}`,
+      );
+    }
+
     try {
       const { txData: nablaApproveTransaction } = this.getPresignedTransaction(state, 'nablaApprove');
       // This is a new item that might not be available on old states.

apps/api/src/api/services/phases/handlers/pendulum-moonbeam-phase-handler.ts

@@ -1,10 +1,19 @@
-import { RampPhase, decodeSubmittableExtrinsic, getAddressForFormat } from '@packages/shared';
+import {
+  AXL_USDC_MOONBEAM,
+  FiatToken,
+  RampPhase,
+  decodeSubmittableExtrinsic,
+  getAddressForFormat,
+  getAnyFiatTokenDetailsMoonbeam,
+} from '@packages/shared';
 import RampState from '../../../../models/rampState.model';
 import { BasePhaseHandler } from '../base-phase-handler';
 
-import { submitXTokens } from '../../xcm/send';
-
+import Big from 'big.js';
+import { moonbeam } from 'viem/chains';
+import { getEvmTokenBalance } from '../../moonbeam/balance';
 import { ApiManager } from '../../pendulum/apiManager';
+import { submitXTokens } from '../../xcm/send';
 import { StateMetadata } from '../meta-state-types';
 
 export class PendulumToMoonbeamXCMPhaseHandler extends BasePhaseHandler {
@@ -14,16 +23,33 @@ export class PendulumToMoonbeamXCMPhaseHandler extends BasePhaseHandler {
 
   protected async executePhase(state: RampState): Promise<RampState> {
     const apiManager = ApiManager.getInstance();
-    const networkName = 'pendulum';
-    const pendulumNode = await apiManager.getApi(networkName);
+    const pendulumNode = await apiManager.getApi('pendulum');
 
-    const { pendulumEphemeralAddress } = state.state as StateMetadata;
+    const { pendulumEphemeralAddress, moonbeamEphemeralAddress, outputAmountBeforeFinalStep, outputTokenType } =
+      state.state as StateMetadata;
 
-    if (!pendulumEphemeralAddress) {
-      throw new Error('Pendulum ephemeral address is not defined in the state. This is a bug.');
+    if (!pendulumEphemeralAddress || !moonbeamEphemeralAddress) {
+      throw new Error('Ephemeral address(es) not defined in the state. This is a bug.');
     }
 
+    const didInputTokenArrivedOnMoonbeam = async () => {
+      // Token is always either axlUSDC or BRL.
+      const tokenAddress =
+        state.type === 'off' ? getAnyFiatTokenDetailsMoonbeam(FiatToken.BRL).moonbeamErc20Address : AXL_USDC_MOONBEAM;
+      const balance = await getEvmTokenBalance({
+        tokenAddress: tokenAddress as `0x${string}`,
+        ownerAddress: moonbeamEphemeralAddress as `0x${string}`,
+        chain: moonbeam,
+      });
+
+      return balance.gte(Big(outputAmountBeforeFinalStep.raw));
+    };
+
     try {
+      if (await didInputTokenArrivedOnMoonbeam()) {
+        return this.transitionToNextPhase(state, this.nextPhaseSelector(state));
+      }
+
       const { txData: pendulumToMoonbeamTransaction } = this.getPresignedTransaction(state, 'pendulumToMoonbeam');
 
       if (typeof pendulumToMoonbeamTransaction !== 'string') {

packages/shared/src/tokens/utils/helpers.ts

@@ -7,7 +7,7 @@ import { assetHubTokenConfig } from '../assethub/config';
 import { evmTokenConfig } from '../evm/config';
 import { moonbeamTokenConfig } from '../moonbeam/config';
 import { stellarTokenConfig } from '../stellar/config';
-import { FiatToken, OnChainToken, RampCurrency } from '../types/base';
+import { FiatToken, OnChainToken, PendulumDetails, RampCurrency } from '../types/base';
 import { AssetHubToken } from '../types/base';
 import { EvmToken } from '../types/evm';
 import { MoonbeamTokenDetails } from '../types/moonbeam';
@@ -115,7 +115,7 @@ export function getPendulumCurrencyId(fiatToken: FiatToken) {
 /**
  * Get Pendulum details for a token
  */
-export function getPendulumDetails(tokenType: RampCurrency, network?: Networks) {
+export function getPendulumDetails(tokenType: RampCurrency, network?: Networks): PendulumDetails {
   const tokenDetails = isFiatTokenEnum(tokenType)
     ? getAnyFiatTokenDetails(tokenType)
     : network