[SDK] Fallback to onchain nonce in 7702 execution

Author: joaquim-verges

.changeset/silly-bugs-clean.md

@@ -0,0 +1,5 @@
+---
+"thirdweb": patch
+---
+
+Fallback to onchain nonce in 7702 execution

packages/thirdweb/src/wallets/in-app/core/eip7702/minimal-account.ts

@@ -1,5 +1,6 @@
 import type { Definition, TypedData } from "ox/TypedData";
 import type { Hex, SignableMessage } from "viem";
+import type { Chain } from "../../../../chains/types.js";
 import { getCachedChain } from "../../../../chains/utils.js";
 import type { ThirdwebClient } from "../../../../client/client.js";
 import { getBytecode } from "../../../../contract/actions/get-bytecode.js";
@@ -8,6 +9,7 @@ import {
   type ThirdwebContract,
 } from "../../../../contract/contract.js";
 import { execute } from "../../../../extensions/erc7702/__generated__/MinimalAccount/write/execute.js";
+import { getRpcClient } from "../../../../rpc/rpc.js";
 import type { SignedAuthorization } from "../../../../transaction/actions/eip7702/authorization.js";
 import { toSerializableTransaction } from "../../../../transaction/actions/to-serializable-transaction.js";
 import type { SendTransactionResult } from "../../../../transaction/types.js";
@@ -49,9 +51,16 @@ export const create7702MinimalAccount = (args: {
     const isMinimalAccount = await is7702MinimalAccount(eoaContract);
     if (!isMinimalAccount) {
       // if not, sign authorization
-      const nonce = firstTx.nonce
-        ? BigInt(firstTx.nonce) + (sponsorGas ? 0n : 1n)
-        : 0n; // TODO (7702): get remote nonce if not provided, should be in the tx though
+      let nonce = firstTx.nonce
+        ? BigInt(firstTx.nonce)
+        : BigInt(
+            await getNonce({
+              client,
+              address: adminAccount.address,
+              chain: getCachedChain(firstTx.chainId),
+            }),
+          );
+      nonce += sponsorGas ? 0n : 1n;
       const auth = await adminAccount.signAuthorization?.({
         address: MINIMAL_ACCOUNT_IMPLEMENTATION_ADDRESS,
         chainId: firstTx.chainId,
@@ -170,6 +179,27 @@ export const create7702MinimalAccount = (args: {
   return minimalAccount;
 };
 
+async function getNonce(args: {
+  client: ThirdwebClient;
+  address: string;
+  chain: Chain;
+}): Promise<number> {
+  const { client, address, chain } = args;
+  const rpcRequest = getRpcClient({
+    chain,
+    client,
+  });
+  const nonce = await import(
+    "../../../../rpc/actions/eth_getTransactionCount.js"
+  ).then(({ eth_getTransactionCount }) =>
+    eth_getTransactionCount(rpcRequest, {
+      address,
+      blockTag: "pending",
+    }),
+  );
+  return nonce;
+}
+
 async function is7702MinimalAccount(
   eoaContract: ThirdwebContract,
 ): Promise<boolean> {