fix(sdk-coin-ada): token verifytransaction

TICKET: COIN-7292

Author: akarath

modules/sdk-coin-ada/src/adaToken.ts

@@ -1,6 +1,15 @@
 import { Ada } from './ada';
-import { BitGoBase, CoinConstructor, NamedCoinConstructor } from '@bitgo/sdk-core';
+import {
+  BitGoBase,
+  CoinConstructor,
+  NamedCoinConstructor,
+  VerifyTransactionOptions,
+  NodeEnvironmentError,
+} from '@bitgo/sdk-core';
 import { coins, tokens, AdaTokenConfig } from '@bitgo/statics';
+import { Transaction } from './lib';
+import * as CardanoWasm from '@emurgo/cardano-serialization-lib-nodejs';
+import assert from 'assert';
 
 export class AdaToken extends Ada {
   public readonly tokenConfig: AdaTokenConfig;
@@ -85,4 +94,72 @@ export class AdaToken extends Ada {
   get contractAddress() {
     return this.tokenConfig.contractAddress;
   }
+
+  /**
+   * Verify that a token transaction prebuild complies with the original intention.
+   * For token transfers, we need to verify the token amount in multiAssets, not the ADA amount.
+   * For token consolidation, we verify all outputs go to the base address.
+   *
+   * @param params.txPrebuild prebuild transaction
+   * @param params.txParams transaction parameters
+   * @param params.verification verification options (includes consolidationToBaseAddress flag)
+   * @param params.wallet wallet object for getting base address
+   * @return true if verification success
+   */
+  async verifyTransaction(params: VerifyTransactionOptions): Promise<boolean> {
+    try {
+      const coinConfig = coins.get(this.getBaseChain());
+      const { txPrebuild, txParams, verification, wallet } = params;
+      const transaction = new Transaction(coinConfig);
+      assert(txPrebuild.txHex, new Error('missing required tx prebuild property txHex'));
+
+      transaction.fromRawTransaction(txPrebuild.txHex);
+      const txJson = transaction.toJson();
+
+      if (txParams.recipients !== undefined) {
+        // assetName in tokenConfig is ASCII (e.g. 'WATER'), convert to hex for comparison
+        const asciiEncodedAssetName = Buffer.from(this.tokenConfig.assetName).toString('hex');
+
+        // ASCII encoded asset name may be appended to the policy ID (consistent with crypto compare)
+        // But cardano sdk requires only the policy ID (28 bytes = 56 hex chars) for ScriptHash
+        let policyId = this.tokenConfig.policyId;
+        if (policyId.endsWith(asciiEncodedAssetName)) {
+          policyId = policyId.substring(0, policyId.length - asciiEncodedAssetName.length);
+        }
+
+        const policyScriptHash = CardanoWasm.ScriptHash.from_hex(policyId);
+        const assetName = CardanoWasm.AssetName.new(Buffer.from(asciiEncodedAssetName, 'hex'));
+
+        for (const recipient of txParams.recipients) {
+          const found = txJson.outputs.some((output) => {
+            if (recipient.address !== output.address || !output.multiAssets) {
+              return false;
+            }
+            const multiAssets = output.multiAssets as CardanoWasm.MultiAsset;
+            const tokenQty = multiAssets.get_asset(policyScriptHash, assetName);
+            return tokenQty && tokenQty.to_str() === recipient.amount;
+          });
+
+          if (!found) {
+            throw new Error('cannot find recipient in expected output');
+          }
+        }
+      } else if (verification?.consolidationToBaseAddress) {
+        // For token consolidation, verify all outputs go to the base address
+        const baseAddress = wallet?.coinSpecific()?.baseAddress || wallet?.coinSpecific()?.rootAddress;
+
+        for (const output of txJson.outputs) {
+          if (output.address !== baseAddress) {
+            throw new Error('tx outputs does not match with expected address');
+          }
+        }
+      }
+    } catch (e) {
+      if (e instanceof NodeEnvironmentError) {
+        return true;
+      }
+      throw e;
+    }
+    return true;
+  }
 }