feat: locally store assets

src/lib/assets.ts

@@ -0,0 +1,69 @@
+import { mkdir, readdir } from "node:fs/promises";
+import { join } from "node:path";
+import { file, hash, write } from "bun";
+import { TTLCache } from "enka.ts";
+import { AvatarStore } from "@/type/enka";
+
+export const cache = new TTLCache();
+
+export class AssetManager {
+  private cache = new Map<string, ArrayBuffer>();
+
+  async getMissingAssets() {
+    const store = await getEnkaAvatarStore();
+    await mkdir("store").catch(() => {});
+    const existing = await readdir("store");
+    const missing = new Set<string>();
+    Object.values(store)
+      .flatMap((a) => [
+        ...a.Consts,
+        ...Object.values(a.Skills),
+        a.SideIconName.replace("AvatarIcon_Side", "Gacha_AvatarImg"),
+      ])
+      .map((n) => existing.includes(hash(n).toString(36)) || missing.add(n));
+
+    console.log(
+      `${missing.size} assets missing, ${existing.length} assets in store`,
+    );
+
+    for (const name of missing)
+      await fetch(new URL(name, "https://enka.network"))
+        .then((res) => {
+          if (res.status === 404) {
+            console.warn(`Asset not found: ${name}`);
+            return new ArrayBuffer(0);
+          }
+          if (!res.ok)
+            throw new Error(`Failed to fetch ${name}: ${res.statusText}`);
+          return res.arrayBuffer();
+        })
+        .then((d) => write(`store/${hash(name).toString(36)}`, d));
+
+    console.log("All missing assets fetched and stored");
+  }
+
+  async load(path: string) {
+    if (this.cache.has(path)) return this.cache.get(path)!;
+    const local = file(join("store", hash(path).toString(36)));
+    if (await local.exists()) return local.arrayBuffer();
+
+    const data = await fetch(new URL(path, "https://enka.network")).then(
+      (res) => res.arrayBuffer(),
+    );
+    this.cache.set(path, data);
+    queueMicrotask(() => write(local, data));
+    return data;
+  }
+}
+
+export async function getEnkaAvatarStore(): Promise<AvatarStore> {
+  const cached = cache.get("enkaAvatarStore");
+  if (cached) return cached as AvatarStore;
+
+  const response = await fetch(
+    "https://github.com/EnkaNetwork/API-docs/raw/refs/heads/master/store/gi/avatars.json",
+  );
+  const data = await response.json();
+  cache.set("enkaAvatarStore", data, 86400); // 24 hours
+  return data;
+}