import { ObjectId } from "../driver/mongodb/typings"

/**
 * A single property handler for FindOptionsRelations.
 */
export type FindOptionsRelationsProperty<Property> = Property extends Promise<
    infer I
>
    ? FindOptionsRelationsProperty<NonNullable<I>> | boolean
    : Property extends Array<infer I>
    ? FindOptionsRelationsProperty<NonNullable<I>> | boolean
    : Property extends string
    ? never
    : Property extends number
    ? never
    : Property extends boolean
    ? never
    : Property extends Function
    ? never
    : Property extends Buffer
    ? never
    : Property extends Date
    ? never
    : Property extends ObjectId
    ? never
    : Property extends object
    ? FindOptionsRelations<Property> | boolean
    : boolean

/**
 * Relations find options.
 */
export type FindOptionsRelations<Entity> = {
    [P in keyof Entity]?: P extends "toString"
        ? unknown
        : FindOptionsRelationsProperty<NonNullable<Entity[P]>>
}

/**
 * Relation names to be selected by "relation" defined as string.
 * Old relation mechanism in TypeORM.
 *
 * @deprecated will be removed in the next version, use FindOptionsRelation type notation instead
 */
export type FindOptionsRelationByString = string[]