LRUSet for seenEvents

packages/app/src/Cache/IndexedDB.ts

@@ -1,6 +1,7 @@
 import Dexie, { Table } from "dexie";
 import { TaggedNostrEvent, ReqFilter as Filter } from "@snort/system";
 import * as Comlink from "comlink";
+import LRUSet from "@/Cache/LRUSet";
 
 type Tag = {
   id: string;
@@ -15,7 +16,7 @@ class IndexedDB extends Dexie {
   events!: Table<TaggedNostrEvent>;
   tags!: Table<Tag>;
   private saveQueue: SaveQueueEntry[] = [];
-  private seenEvents = new Set<string>(); // LRU set maybe?
+  private seenEvents = new LRUSet<string>(1000);
   private subscribedEventIds = new Set<string>();
   private subscribedAuthors = new Set<string>();
   private subscribedTags = new Set<string>();

packages/app/src/Cache/LRUSet.ts

@@ -0,0 +1,23 @@
+export default class LRUSet<T> {
+  private set = new Set<T>();
+  private limit: number;
+
+  constructor(limit: number) {
+    this.limit = limit;
+  }
+
+  add(item: T) {
+    if (this.set.size >= this.limit) {
+      this.set.delete(this.set.values().next().value);
+    }
+    this.set.add(item);
+  }
+
+  has(item: T) {
+    return this.set.has(item);
+  }
+
+  values() {
+    return this.set.values();
+  }
+}