fix: order of parameters for sponsor tx

package.json

@@ -1,6 +1,6 @@
 {
   "packageManager": "pnpm@9.4.0",
-  "version": "3.0.0-beta.3",
+  "version": "3.0.0-beta.4",
   "license": "MIT",
   "main": "dist/index.js",
   "typings": "dist/index.d.ts",

src/alexSDK.ts

@@ -11,7 +11,7 @@ import { getAllPossibleRoute } from './helpers/RouteHelper';
 import { getYAmountFromXAmount } from './helpers/RateHelper';
 import { fromEntries } from './utils/utils';
 import type { AMMRoute } from './utils/ammRouteResolver';
-import { broadcastSponsoredTx, requiredStxAmountForSponsorTx, runSponsoredSpotTx } from './helpers/SponsorTxHelper';
+import { broadcastSponsoredTx, requiredStxAmountForSponsorTx, runSponsoredSpotTx, SponsoredTxError, SponsoredTxErrorCode } from './helpers/SponsorTxHelper';
 
 /**
  * The AlexSDK class provides methods for interacting with a decentralized exchange (DEX) system,
@@ -186,11 +186,14 @@ export class AlexSDK {
       to,
       route
     )
-    const sponsorFeeAmount = await this.getAmountTo(
+    const sponsorFeeAmount = from === Currency.STX ? stxAmount : await this.getAmountTo(
       Currency.STX,
       stxAmount,
       from
     )
+    if (sponsorFeeAmount > fromAmount) {
+      return BigInt(0)
+    }
     return getYAmountFromXAmount(
       from,
       to,
@@ -258,11 +261,14 @@ export class AlexSDK {
       currencyY,
       route
     )
-    const sponsorFeeAmount = await this.getAmountTo(
+    const sponsorFeeAmount = currencyX === Currency.STX ? stxAmount : await this.getAmountTo(
       Currency.STX,
       stxAmount,
       currencyX
     )
+    if (sponsorFeeAmount > fromAmount) {
+      throw new SponsoredTxError(SponsoredTxErrorCode.insufficient_funds, 'Insufficient funds to cover sponsor fee')
+    }
     return runSponsoredSpotTx(
       stxAddress,
       currencyX,

src/helpers/SponsorTxHelper.ts

@@ -21,8 +21,8 @@ export function runSponsoredSpotTx(
     currencyX: Currency,
     currencyY: Currency,
     totalAmount: bigint,
-    feeAmount: bigint,
     minDy: bigint,
+    feeAmount: bigint,
     ammPools: PoolData[],
     mappings: TokenInfo[],
     customRoute?: AMMRouteSegment[]
@@ -244,6 +244,8 @@ export enum SponsoredTxErrorCode {
     "invalid_nonce" = "invalid_nonce",
     // Worker failed to broadcast the tx
     "broadcast_error" = "broadcast_error",
+    // Insufficient funds to cover sponsor fee
+    "insufficient_funds" = "insufficient_funds",
     "unknown_error" = "unknown_error",
 }