import { FindOperator } from './FindOperator';

import { EqualOperator } from './EqualOperator';

/**
 * A single property handler for FindOptionsWhere.
 *
 * The reason why we have both "PropertyToBeNarrowed" and "Property" is that Union is narrowed down when extends is used.
 * It means the result of FindOptionsWhereProperty<1 | 2> doesn't include FindOperator<1 | 2> but FindOperator<1> | FindOperator<2>.
 * So we keep the original Union as Original and pass it to the FindOperator too. Original remains Union as extends is not used for it.
 */
export type FindOptionsWhereProperty<
	PropertyToBeNarrowed,
	Property = PropertyToBeNarrowed,
> = PropertyToBeNarrowed extends Promise<infer I>
	? FindOptionsWhereProperty<NonNullable<I>>
	: PropertyToBeNarrowed extends Array<infer I>
		? FindOptionsWhereProperty<NonNullable<I>>
		: PropertyToBeNarrowed extends Function
			? never
			: PropertyToBeNarrowed extends Buffer
				? Property | FindOperator<Property>
				: PropertyToBeNarrowed extends Date
					? Property | FindOperator<Property>
					: PropertyToBeNarrowed extends string
						? Property | FindOperator<Property>
						: PropertyToBeNarrowed extends number
							? Property | FindOperator<Property>
							: PropertyToBeNarrowed extends boolean
								? Property | FindOperator<Property>
								: PropertyToBeNarrowed extends object
									?
											| FindOptionsWhere<Property>
											| FindOptionsWhere<Property>[]
											| EqualOperator<Property>
											| FindOperator<any>
											| boolean
											| Property
									: Property | FindOperator<Property>;

/**
 * Used for find operations.
 */
export type FindOptionsWhere<Entity> = {
	[P in keyof Entity]?: P extends 'toString'
		? unknown
		: FindOptionsWhereProperty<NonNullable<Entity[P]>>;
};