hedgedoc/commons/src/permissions/permissions.ts

/*
 * SPDX-FileCopyrightText: 2023 The HedgeDoc developers (see AUTHORS file)
 *
 * SPDX-License-Identifier: AGPL-3.0-only
 */
import { NotePermissions, SpecialGroup } from './permissions.types.js'

/**
 * Checks if the given user is the owner of a note.
 *
 * @param permissions The permissions of the note to check
 * @param user The username of the user
 * @return True if the user is the owner of the note
 */
export const userIsOwner = (
  permissions: NotePermissions,
  user?: string
): boolean => {
  return !!user && permissions.owner === user
}

/**
 * Checks if the given user may edit a note.
 *
 * @param permissions The permissions of the note to check
 * @param user The username of the user
 * @return True if the user has the permission to edit the note
 */
export const userCanEdit = (
  permissions: NotePermissions,
  user?: string
): boolean => {
  const isOwner = userIsOwner(permissions, user)
  const mayWriteViaUserPermission = permissions.sharedToUsers.some(
    (value) => value.canEdit && value.username === user
  )
  const mayWriteViaGroupPermission =
    !!user &&
    permissions.sharedToGroups.some(
      (value) =>
        value.groupName === (SpecialGroup.LOGGED_IN as string) && value.canEdit
    )
  const everyoneMayWriteViaGroupPermission = permissions.sharedToGroups.some(
    (value) =>
      value.groupName === (SpecialGroup.EVERYONE as string) && value.canEdit
  )
  return (
    isOwner ||
    mayWriteViaUserPermission ||
    mayWriteViaGroupPermission ||
    everyoneMayWriteViaGroupPermission
  )
}