add getDecodedWithdrawalAmount (#20)

* add `getDecodedWithdrawalAmount`

* supports btc

Author: clemsos

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@reservoir0x/relay-protocol-sdk",
-  "version": "0.0.51",
+  "version": "0.0.52",
   "description": "Relay protocol SDK",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",

src/index.ts

@@ -25,6 +25,7 @@ import {
   decodeWithdrawal,
   getDecodedWithdrawalId,
   getDecodedWithdrawalCurrency,
+  getDecodedWithdrawalAmount,
 } from "./messages/v2.1/depository-withdrawal";
 
 import {
@@ -95,6 +96,7 @@ export {
   decodeWithdrawal,
   getDecodedWithdrawalId,
   getDecodedWithdrawalCurrency,
+  getDecodedWithdrawalAmount,
 
   // SolverRefund
   SolverRefundMessage,

src/messages/v2.1/depository-withdrawal.ts

@@ -4,6 +4,7 @@ import { bcs } from "@mysten/sui/bcs";
 import { PublicKey, SystemProgram } from "@solana/web3.js";
 import { sha256 } from "js-sha256";
 import * as tronweb from "tronweb";
+import * as bitcoin from "bitcoinjs-lib";
 import {
   Address,
   bytesToHex,
@@ -787,3 +788,74 @@ export const getDecodedWithdrawalCurrency = (
     }
   }
 };
+
+const decodeERC20TransferAmount = (data: string) => {
+  // ERC20 / TRC20 `transfer(address,uint256)` selector is 0xa9059cbb
+  const TRANSFER_SELECTOR = "0xa9059cbb";
+  if (data.toLowerCase().startsWith(TRANSFER_SELECTOR.toLowerCase())) {
+    const paramsData = ("0x" + data.slice(TRANSFER_SELECTOR.length)) as Hex;
+    const [amount] = decodeAbiParameters(
+      parseAbiParameters(["address", "uint256"]),
+      paramsData
+    );
+    return amount;
+  } else {
+    throw new Error(`Unsupported function call data: ${data}`);
+  }
+};
+
+export const getDecodedWithdrawalAmount = (
+  decodedWithdrawal: DecodedWithdrawal
+): string => {
+  switch (decodedWithdrawal.vmType) {
+    case "ethereum-vm": {
+      const firstCall = decodedWithdrawal.withdrawal.calls[0];
+      if (firstCall.data === "0x") {
+        return firstCall.value;
+      } else {
+        return decodeERC20TransferAmount(firstCall.data);
+      }
+    }
+
+    case "tron-vm": {
+      const firstCall = decodedWithdrawal.withdrawal.calls[0];
+      if (firstCall.data === "0x") {
+        return firstCall.value;
+      } else {
+        return decodeERC20TransferAmount(firstCall.data);
+      }
+    }
+
+    case "solana-vm": {
+      return decodedWithdrawal.withdrawal.amount;
+    }
+
+    case "sui-vm": {
+      return decodedWithdrawal.withdrawal.amount;
+    }
+
+    case "bitcoin-vm": {
+      try {
+        const psbt = bitcoin.Psbt.fromHex(decodedWithdrawal.withdrawal.psbt);
+        const tx = psbt.extractTransaction(false);
+        const totalAmount = tx.outs.reduce((sum, output) => {
+          return sum + output.value;
+        }, 0);
+        return totalAmount.toString();
+      } catch (error) {
+        throw new Error(
+          `Failed to decode PSBT: ${
+            error instanceof Error ? error.message : String(error)
+          }`
+        );
+      }
+    }
+
+    case "hyperliquid-vm": {
+      return decodedWithdrawal.withdrawal.parameters.amount;
+    }
+
+    default:
+      throw new Error("Unsupported vm type");
+  }
+};