From 3b3f7d3f6a6537aabc3c7c9753ea66903aa3e00b Mon Sep 17 00:00:00 2001
From: Emmo00 <nwaforemmanuel005@gmail.com>
Date: Wed, 8 Oct 2025 11:27:14 +0100
Subject: [PATCH] fix: update latest nonce with onchain + local state

---
 src/logic/mqtt.ts   | 22 ++++++++++------------
 src/logic/sync.ts   | 32 ++++++++++++++++++++++++++++++--
 src/store/sqlite.ts | 30 ++++++++++++++++++++++++++++--
 3 files changed, 68 insertions(+), 16 deletions(-)

diff --git a/src/logic/mqtt.ts b/src/logic/mqtt.ts
index a3e9966..6bdd19e 100644
--- a/src/logic/mqtt.ts
+++ b/src/logic/mqtt.ts
@@ -16,7 +16,7 @@ import { State, TransactionRecord } from "../types";
 import { getProverURL, sendPendingTransactionsToProver } from "./verify";
 import { decodePayload } from "./decode";
 import { verifyPayloadSignature } from "../utils";
-import { pruneAndSyncOnchain } from "./sync";
+import { getLatestTransactionNonce, pruneAndSyncOnchain } from "./sync";
 
 const SYNC_EPOCH = 100; // after 100 transactions, sync with blockchain
 
@@ -95,9 +95,13 @@ export async function handleMessage(blob: Buffer) {
         //   throw new Error("Token ID not found for public key: " + publicKey);
         // }
 
-        const latestNonce = Number(await rollupContract.nonce(tokenId));
+        const latestNonce = await getLatestTransactionNonce(tokenId);
 
-        console.log("[info] Fetched tokenId and latestNonce from chain:", tokenId, latestNonce);
+        console.log(
+          "[info] Fetched tokenId and latestNonce from chain and local state:",
+          tokenId,
+          latestNonce
+        );
 
         // save new meter with devEui
         const newMeter = {
@@ -114,9 +118,9 @@ export async function handleMessage(blob: Buffer) {
         updateMeterDevEui(`0x${publicKey}`, message["deviceInfo"]["devEui"]);
 
         // fetch and update latest nonce from chain
-        const latestNonce = Number(await rollupContract.nonce(existingMeter.tokenId));
+        const latestNonce = await getLatestTransactionNonce(existingMeter.tokenId);
 
-        console.log("[info] Fetched latestNonce from chain:", latestNonce);
+        console.log("[info] Fetched latestNonce from chain and local state:", latestNonce);
 
         updateMeterNonce(`0x${publicKey}`, latestNonce);
       }
@@ -178,13 +182,7 @@ export async function handleMessage(blob: Buffer) {
         raw: transactionHex.toString("hex"),
       } as TransactionRecord;
 
-      try {
-        insertTransaction(transactionRecord);
-
-        console.log("[info] Inserted transaction record:", transactionRecord);
-      } catch (error) {
-        console.error("Error inserting transaction:", error);
-      }
+      insertTransaction(transactionRecord);
 
       updateMeterNonce(`0x${publicKey}`, expectedNonce);
 
diff --git a/src/logic/sync.ts b/src/logic/sync.ts
index 8766041..ade23c9 100644
--- a/src/logic/sync.ts
+++ b/src/logic/sync.ts
@@ -1,8 +1,18 @@
-import { getMeterByPublicKey, getMeterByTokenId, pruneTransactionsBefore, updateMeterNonce } from "../store/sqlite";
+import {
+  getMeterByPublicKey,
+  getMeterByTokenId,
+  getTransactionByNonce,
+  pruneTransactionsAfter,
+  pruneTransactionsBefore,
+  updateMeterNonce,
+} from "../store/sqlite";
 import { rollup as rollupContract } from "./context";
 
 export async function pruneAndSyncOnchain(meterIdentifier: number | string): Promise<number> {
-  const meter = typeof meterIdentifier === "number" ? getMeterByTokenId(meterIdentifier) : getMeterByPublicKey(meterIdentifier);
+  const meter =
+    typeof meterIdentifier === "number"
+      ? getMeterByTokenId(meterIdentifier)
+      : getMeterByPublicKey(meterIdentifier);
 
   if (!meter) {
     throw new Error(`Meter with identifier ${meterIdentifier} not found`);
@@ -22,3 +32,21 @@ export async function pruneAndSyncOnchain(meterIdentifier: number | string): Pro
 
   return onchainNonce;
 }
+
+export async function getLatestTransactionNonce(meterIdentifier: number): Promise<number> {
+  // get latest nonce from chain
+  let latestNonce = Number(await rollupContract.nonce(meterIdentifier));
+
+  // check local state for the highest nonce we have
+  while (true) {
+    const existingTransaction = getTransactionByNonce(latestNonce + 1, meterIdentifier);
+    if (existingTransaction) {
+      latestNonce += 1;
+    } else {
+      pruneTransactionsAfter(latestNonce, meterIdentifier);
+      break;
+    }
+  }
+
+  return latestNonce;
+}
diff --git a/src/store/sqlite.ts b/src/store/sqlite.ts
index 652dbc3..13cb20f 100644
--- a/src/store/sqlite.ts
+++ b/src/store/sqlite.ts
@@ -2,6 +2,7 @@ import fs from "fs";
 import Database from "better-sqlite3";
 import type { Database as DatabaseType, Statement as DatabaseStatementType } from "better-sqlite3";
 import { MeterRecord, TransactionRecord } from "../types";
+import { get } from "http";
 
 // meter queries
 let db: DatabaseType;
@@ -219,13 +220,25 @@ export function updateMeterDevEui(publicKey: string, devEui: string): boolean {
   }
 }
 
+export function getTransactionByNonce(nonce: number, identifier: number): TransactionRecord | null {
+  try {
+    const result = getTransactionByNonceQuery.get(nonce, identifier) as
+      | TransactionRecord
+      | undefined;
+    return result || null;
+  } catch (err: any) {
+    console.error("Failed to get transaction by nonce:", err);
+    return null;
+  }
+}
+
 // Transaction insertion function
 export function insertTransaction(transactionData: TransactionRecord): void {
   try {
-    const existingTransaction = getTransactionByNonceQuery.get(
+    const existingTransaction = getTransactionByNonce(
       transactionData.nonce,
       transactionData.identifier
-    ) as TransactionRecord | undefined;
+    );
 
     if (existingTransaction) {
       throw new Error(`Transaction with nonce ${transactionData.nonce} already exists`);
@@ -260,3 +273,16 @@ export function pruneTransactionsBefore(nonce: number, meterNumber: number) {
     console.error("Failed to prune transactions:", err);
   }
 }
+
+export function pruneTransactionsAfter(nonce: number, meterNumber: number) {
+  try {
+    const result = db
+      .prepare(`DELETE FROM transactions WHERE identifier = ? AND nonce > ?`)
+      .run(meterNumber, nonce);
+    console.log(
+      `Pruned ${result.changes} transactions for meter ${meterNumber} with nonce > ${nonce}`
+    );
+  } catch (err: any) {
+    console.error("Failed to prune transactions:", err);
+  }
+}