From e288d56181160db4e363bc46a4a55ef06c3a2c03 Mon Sep 17 00:00:00 2001
From: tamaina <tamaina@hotmail.co.jp>
Date: Wed, 26 Jul 2023 16:40:42 +0000
Subject: [PATCH] perf(frontend): Notes Manager

---
 .../frontend/src/scripts/entity-manager.ts    | 94 +++++++++++++++++++
 1 file changed, 94 insertions(+)
 create mode 100644 packages/frontend/src/scripts/entity-manager.ts

diff --git a/packages/frontend/src/scripts/entity-manager.ts b/packages/frontend/src/scripts/entity-manager.ts
new file mode 100644
index 0000000000..269c143b0e
--- /dev/null
+++ b/packages/frontend/src/scripts/entity-manager.ts
@@ -0,0 +1,94 @@
+import { Note, UserLite } from "misskey-js/built/entities";
+import { Ref, ref, ComputedRef, computed } from "vue";
+import { api } from "./api";
+
+export class EntitiyManager<T extends { id: string }> {
+    private entities: Map<T['id'], Ref<T>>;
+
+    constructor() {
+        this.entities = new Map();
+    }
+
+    public set(item: T): Ref<T> {
+        const cached = this.entities.get(item.id);
+        if (cached) {
+            cached.value = item;
+        } else {
+            this.entities.set(item.id, ref(item) as Ref<T>);
+        }
+        return this.get(item.id)!;
+    }
+
+    public get(id: string): Ref<T> | undefined {
+        return this.entities.get(id);
+    }
+}
+
+export const userLiteManager = new EntitiyManager<UserLite>();
+
+type OmittedNote = Omit<Note, 'user' | 'renote' | 'reply'>;
+type InternalCachedNote = Ref<OmittedNote>;
+
+export class NoteManager {
+    private notes: Map<Note['id'], InternalCachedNote>;
+    private updatedAt: Map<Note['id'], number>;
+    private captureing: Map<Note['id'], number>;
+
+    constructor() {
+        this.notes = new Map();
+        this.updatedAt = new Map();
+        this.captureing = new Map();
+    }
+
+    public set(_note: Note): ComputedRef<Note> {
+        const note: Note = { ..._note };
+        userLiteManager.set(note.user);
+        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+        //@ts-ignore
+        delete note.user;
+        if (note.renote) this.set(note.renote);
+        delete note.renote;
+        if (note.reply) this.set(note.reply);
+        delete note.reply;
+        const cached = this.notes.get(note.id);
+        if (cached) {
+            cached.value = note;
+        } else {
+            this.notes.set(note.id, ref(note));
+        }
+        this.updatedAt.set(note.id, Date.now());
+        return this.get(note.id)!;
+    }
+
+    public get(id: string): ComputedRef<Note> | undefined {
+        const note: InternalCachedNote | undefined = this.notes.get(id);
+        if (!note) return undefined;
+
+        return computed<Note>(() => {
+            const user = userLiteManager.get(note.value.userId)!;
+            const renote = note.value.renoteId ? this.get(note.value.renoteId) : undefined;
+            const reply = note.value.replyId ? this.get(note.value.replyId) : undefined;
+
+            return {
+                ...note.value,
+                user: user.value,
+                renote: renote?.value,
+                reply: reply?.value,
+            };
+        });
+    }
+
+    public async fetch(id: string, force = false): Promise<ComputedRef<Note>> {
+        if (!force) {
+            const updatedAt = this.updatedAt.get(id);
+            if (updatedAt && Date.now() - updatedAt < 1000 * 30) {
+                const cachedNote = this.get(id);
+                if (cachedNote) {
+                    return cachedNote as ComputedRef<Note>;
+                }
+            }
+        }
+        const fetchedNote = await api('notes/show', { noteId: id });
+        return this.set(fetchedNote);
+    }
+}