文件结构更改

packages/hydrooj/src/lib/paginate.ts

@@ -0,0 +1,16 @@
+import { Cursor } from 'mongodb';
+import { ValidationError } from '../error';
+
+export default async function paginate(
+    cursor: Cursor, page: number, pageSize: number,
+): Promise<[any[]/* docs */, number/* numPages */, number/* count */]> {
+    if (page <= 0) throw new ValidationError('page');
+    const [count, pageDocs] = await Promise.all([
+        cursor.count(),
+        cursor.skip((page - 1) * pageSize).limit(pageSize).toArray(),
+    ]);
+    const numPages = Math.floor((count + pageSize - 1) / pageSize);
+    return [pageDocs, numPages, count];
+}
+
+global.Hydro.lib.paginate = paginate;