export type Nullable<T> = {
	[P in keyof T]: T[P] | null;
};

/**
 * Allows support for TS 4.5's `exactOptionalPropertyTypes` option by ensuring a property present and undefined is valid
 * (since JSON.stringify ignores undefined properties)
 */
export type AddUndefinedToPossiblyUndefinedPropertiesOfInterface<Base> = {
	[K in keyof Base]: Base[K] extends Exclude<Base[K], undefined>
		? AddUndefinedToPossiblyUndefinedPropertiesOfInterface<Base[K]>
		: AddUndefinedToPossiblyUndefinedPropertiesOfInterface<Base[K]> | undefined;
};

export type StrictPartial<Base> = AddUndefinedToPossiblyUndefinedPropertiesOfInterface<Partial<Base>>;

export type StrictRequired<Base> = Required<{ [K in keyof Base]: Exclude<Base[K], undefined> }>;

export type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends (k: infer I) => void ? I : never;

type Keys<T> = keyof T;
type DistributiveKeys<T> = T extends unknown ? Keys<T> : never;
/**
 * Allows picking of keys from unions that are disjoint
 */
export type DistributivePick<T, K extends DistributiveKeys<T>> = T extends unknown
	? keyof Pick_<T, K> extends never
		? never
		: { [P in keyof Pick_<T, K>]: Pick_<T, K>[P] }
	: never;

type Pick_<T, K> = Pick<T, Extract<keyof T, K>>;

/**
 * Allows omitting of keys from unions that are disjoint
 */
export type DistributiveOmit<T, K extends DistributiveKeys<T>> = T extends unknown
	? { [P in keyof Omit_<T, K>]: Omit_<T, K>[P] }
	: never;

type Omit_<T, K> = Omit<T, Extract<keyof T, K>>;