WIP

yarn-project/pxe/src/simulator_oracle/index.ts

@@ -38,7 +38,7 @@ import { type IncomingNoteDao } from '../database/incoming_note_dao.js';
 import { type PxeDatabase } from '../database/index.js';
 import { produceNoteDaos } from '../note_decryption_utils/produce_note_daos.js';
 import { getAcirSimulator } from '../simulator/index.js';
-import { INDEX_OFFSET, getInitialSearchState } from './tagging_utils.js';
+import { WINDOW_HALF_SIZE, getLeftMostIndexedTaggingSecrets, getInitialSecretIndexes, getRightMostIndexes } from './tagging_utils.js';
 
 /**
  * A data oracle that provides information needed for simulating a transaction.
@@ -432,7 +432,7 @@ export class SimulatorOracle implements DBOracle {
       // know how many logs we will get back. Furthermore, these logs are of undetermined
       // length, since we don't really know the note they correspond to until we decrypt them.
 
-      // 1. Get all the secrets for the recipient and sender pairs
+      // 1. Get all the secrets for the recipient and sender pairs (#9365)
       const indexedTaggingSecrets = await this.#getIndexedTaggingSecretsForContacts(contractAddress, recipient);
 
       // 1.1 Set up a sliding window with an offset. Chances are the sender might have messed up
@@ -442,10 +442,12 @@ export class SimulatorOracle implements DBOracle {
       //    Also there's a possibility that we have advanced our index, but the sender has reused it,
       // so we might have missed some logs. For these reasons, we have to look both back and ahead of
       // the stored index.
-      const searchState = getInitialSearchState(indexedTaggingSecrets);
-
-      let { currentTaggingSecrets } = searchState;
-      const { maxIndexesToCheck, secretsToIncrement, initialSecretIndexes } = searchState;
+      let currentTaggingSecrets = getLeftMostIndexedTaggingSecrets(indexedTaggingSecrets);
+      // Max indexes to check sorted in a key-value map where key is the app tagging secret and value is the max index
+      // to check (the right-most index in the window).
+      const indexedRightMostIndexes = getRightMostIndexes(indexedTaggingSecrets);
+      const initialSecretIndexes = getInitialSecretIndexes(indexedTaggingSecrets);
+      const secretsToIncrement: { [k: string]: number } = {};
 
       while (currentTaggingSecrets.length > 0) {
         // 2. Compute tags using the secrets, recipient and index. Obtain logs for each tag (#9380)
@@ -484,12 +486,12 @@ export class SimulatorOracle implements DBOracle {
               // we have stored in the db (#9380)
               secretsToIncrement[currentSecretAsStr] = newIndex;
               // 3.3. Slide the window forwards if we have found logs beyond the initial index
-              maxIndexesToCheck[currentSecretAsStr] = currentIndex + INDEX_OFFSET;
+              indexedRightMostIndexes[currentSecretAsStr] = currentIndex + WINDOW_HALF_SIZE;
             }
           }
           // 3.4 Keep increasing the index (inside the window) temporarily for the tags that have no logs
           // There's a chance the sender missed some and we want to catch up
-          if (currentIndex < maxIndexesToCheck[currentSecretAsStr]) {
+          if (currentIndex < indexedRightMostIndexes[currentSecretAsStr]) {
             const newTaggingSecret = new IndexedTaggingSecret(currentSecret, currentIndex + 1);
             newTaggingSecrets.push(newTaggingSecret);
           }

yarn-project/pxe/src/simulator_oracle/tagging_utils.ts

@@ -1,36 +1,32 @@
 import { IndexedTaggingSecret } from '@aztec/circuits.js';
 
-type SearchState = {
-  currentTaggingSecrets: IndexedTaggingSecret[];
-  maxIndexesToCheck: { [k: string]: number };
-  initialSecretIndexes: { [k: string]: number };
-  secretsToIncrement: { [k: string]: number };
-};
-
-export const INDEX_OFFSET = 10;
-
-export function getInitialSearchState(appTaggingSecrets: IndexedTaggingSecret[]) {
-  const searchState = appTaggingSecrets.reduce<SearchState>(
-    (acc, appTaggingSecret) => ({
-      // Start looking for logs before the stored index
-      currentTaggingSecrets: acc.currentTaggingSecrets.concat([
-        new IndexedTaggingSecret(appTaggingSecret.appTaggingSecret, Math.max(0, appTaggingSecret.index - INDEX_OFFSET)),
-      ]),
-      // Keep looking for logs beyond the stored index
-      maxIndexesToCheck: {
-        ...acc.maxIndexesToCheck,
-        ...{ [appTaggingSecret.appTaggingSecret.toString()]: appTaggingSecret.index + INDEX_OFFSET },
-      },
-      // Keeps track of the secrets we have to increment in the database
-      secretsToIncrement: {},
-      // Store the initial set of indexes for the secrets
-      initialSecretIndexes: {
-        ...acc.initialSecretIndexes,
-        ...{ [appTaggingSecret.appTaggingSecret.toString()]: appTaggingSecret.index },
-      },
-    }),
-    { currentTaggingSecrets: [], maxIndexesToCheck: {}, secretsToIncrement: {}, initialSecretIndexes: {} },
+export const WINDOW_HALF_SIZE = 10;
+
+export function getLeftMostIndexedTaggingSecrets(indexedTaggingSecrets: IndexedTaggingSecret[]): IndexedTaggingSecret[] {
+  return indexedTaggingSecrets.map(indexedTaggingSecret =>
+    new IndexedTaggingSecret(
+      indexedTaggingSecret.appTaggingSecret,
+      Math.max(0, indexedTaggingSecret.index - WINDOW_HALF_SIZE)
+    )
   );
+}
+
+export function getRightMostIndexes(indexedTaggingSecrets: IndexedTaggingSecret[]): { [k: string]: number } {
+  const maxIndexesToCheck: { [k: string]: number } = {};
+
+  for (const indexedTaggingSecret of indexedTaggingSecrets) {
+    maxIndexesToCheck[indexedTaggingSecret.appTaggingSecret.toString()] = indexedTaggingSecret.index + WINDOW_HALF_SIZE;
+  }
 
-  return searchState;
+  return maxIndexesToCheck;
 }
+
+export function getInitialSecretIndexes(indexedTaggingSecrets: IndexedTaggingSecret[]): { [k: string]: number } {
+  const initialSecretIndexes: { [k: string]: number } = {};
+
+  for (const indexedTaggingSecret of indexedTaggingSecrets) {
+    initialSecretIndexes[indexedTaggingSecret.appTaggingSecret.toString()] = indexedTaggingSecret.index;
+  }
+
+  return initialSecretIndexes;
+}