valia/src/schema/formats/struct/types.ts

A runtime data validator in TypeScript with advanced type inference, built-in validation functions, and seamless integration for server and client environments.

import type { SetableCriteriaTemplate, ClassicTypesTemplate, GenericTypesTemplate, KeyofFormatClassicTypes,
	SetableCriteria, GuardedCriteria, MountedCriteria } from "../types";

export type StructCriteria<T extends KeyofFormatClassicTypes = KeyofFormatClassicTypes> = {
    [key: string | symbol]: SetableCriteria<T> | StructCriteria<T>;
};

export interface StructSetableCriteria<
	T extends KeyofFormatClassicTypes = KeyofFormatClassicTypes
> extends SetableCriteriaTemplate<"struct"> {
	optional?: (string | symbol)[];
	struct: StructCriteria<T>;
}

export interface StructClassicTypes<T extends KeyofFormatClassicTypes> extends ClassicTypesTemplate<
	StructSetableCriteria<T>,
	{}
> {}

type SimulateStruct<T> = StructSetableCriteria & { struct: T; };

type MountedStruct<T extends StructCriteria> = {
	[K in keyof T]:
		T[K] extends SetableCriteria
			? MountedCriteria<T[K]>
			: T[K] extends StructCriteria
				? MountedCriteria<SimulateStruct<T[K]>>
				: T[K] extends (SetableCriteria | StructCriteria)
					? MountedCriteria<SetableCriteria>
					: T[K];
};

export interface StructMountedCriteria<T extends StructSetableCriteria> {
	struct: MountedStruct<T['struct']>;
	acceptedKeys: (string | symbol)[];
	requiredKeys: (string | symbol)[];
}

type OmitDynamicKey<K extends PropertyKey> = {} extends Record<K, unknown> ? never : K;

type OptionalizeKey<T, K extends (string | symbol)[] | undefined> = 
	K extends PropertyKey[]
		? Omit<T, K[number]> & Partial<Omit<T, keyof Omit<T, K[number]>>> 
		: T;

type StructGuardedCriteria<T extends StructSetableCriteria> = {
	-readonly [K in keyof OptionalizeKey<T['struct'], T['optional']> as OmitDynamicKey<K>]:
		T['struct'][K] extends SetableCriteria
			? GuardedCriteria<T['struct'][K]>
			: T['struct'][K] extends StructCriteria
				? GuardedCriteria<SimulateStruct<T['struct'][K]>>
				: never;
};

export interface StructGenericTypes<T extends StructSetableCriteria > extends GenericTypesTemplate<
	StructMountedCriteria<T>,
	StructGuardedCriteria<T>
> {}