import { Document } from 'mongoose';

import type { IAttachment, IUser } from '~/interfaces';

import { isPopulated, isRef, type Ref } from '../../interfaces/common';
import {
  type IUserSerializedSecurely,
  serializeUserSecurely,
} from './user-serializer';

export type IAttachmentSerializedSecurely<A extends IAttachment> = Omit<
  A,
  'creator'
> & { creator?: Ref<IUserSerializedSecurely<IUser>> };

const omitInsecureAttributes = <A extends IAttachment>(
  attachment: A,
): IAttachmentSerializedSecurely<A> => {
  const leanDoc =
    attachment instanceof Document ? attachment.toObject<A>() : attachment;

  const { creator, ...rest } = leanDoc;

  const secureCreator =
    creator == null ? undefined : serializeUserSecurely(creator);

  return {
    creator: secureCreator,
    ...rest,
  };
};

export function serializeAttachmentSecurely<A extends IAttachment>(
  attachment?: A,
): IAttachmentSerializedSecurely<A>;
export function serializeAttachmentSecurely<A extends IAttachment>(
  attachment?: Ref<A>,
): Ref<IAttachmentSerializedSecurely<A>>;
export function serializeAttachmentSecurely<A extends IAttachment>(
  attachment?: A | Ref<A>,
):
  | undefined
  | IAttachmentSerializedSecurely<A>
  | Ref<IAttachmentSerializedSecurely<A>> {
  if (attachment == null) return attachment;

  if (isRef(attachment) && !isPopulated(attachment)) return attachment;

  return omitInsecureAttributes(attachment);
}