Merge remote-tracking branch 'mmalmi/main'

packages/app/src/Cache/FollowListCache.ts

@@ -0,0 +1,48 @@
+import { db } from "Db";
+import { unixNowMs } from "@snort/shared";
+import { EventKind, RequestBuilder, TaggedNostrEvent } from "@snort/system";
+import { RefreshFeedCache } from "./RefreshFeedCache";
+import { LoginSession } from "Login";
+import SocialGraph from "SocialGraph/SocialGraph";
+
+export class FollowListCache extends RefreshFeedCache<TaggedNostrEvent> {
+  constructor() {
+    super("FollowListCache", db.followLists);
+  }
+
+  buildSub(session: LoginSession, rb: RequestBuilder): void {
+    const since = this.newest();
+    rb.withFilter()
+      .kinds([EventKind.ContactList])
+      .authors(session.follows.item)
+      .since(since === 0 ? undefined : since);
+  }
+
+  async onEvent(evs: readonly TaggedNostrEvent[]) {
+    await Promise.all(
+      evs.map(async e => {
+        const update = await super.update({
+          ...e,
+          created: e.created_at,
+          loaded: unixNowMs(),
+        });
+        if (update !== "no_change") {
+          SocialGraph.handleFollowEvent(e);
+        }
+      }),
+    );
+  }
+
+  key(of: TaggedNostrEvent): string {
+    return of.pubkey;
+  }
+
+  takeSnapshot() {
+    return [...this.cache.values()];
+  }
+
+  override async preload() {
+    await super.preload();
+    this.snapshot().forEach(e => SocialGraph.handleFollowEvent(e));
+  }
+}