import { DataResponse } from "../../model/response.js";
import "../../model/index.js";
//#region src/sdk/utils/types.d.ts
/**
 * Whether a merge could have been given nothing at all, i.e. both sides are
 * typed as possibly absent. One definite side already answers this `false`.
 **/
type BothMayBeMissing<Onchain, Offchain> = undefined extends Onchain & Offchain ? true : false;
/**
 * What merging two lists answers with: an envelope unless both sides could
 * still be missing, since a list merge serves whichever side did arrive.
 *
 * @typeParam Onchain - What the on-chain side was given as.
 * @typeParam Offchain - What the backend side was given as.
 * @typeParam T - Payload type of the read.
 **/
export type MergeListResult<Onchain, Offchain, T> = BothMayBeMissing<Onchain, Offchain> extends true ? DataResponse<T> | undefined : DataResponse<T>;
/**
 * What narrowing an already-read list answers with: `undefined` only where the
 * read itself was still in flight.
 *
 * @typeParam R - What the response was given as.
 * @typeParam T - Row type.
 **/
export type FilterResult<R, T> = R extends undefined ? undefined : DataResponse<T[]>;
/**
 * How a list read combines what the two sources returned. A side still in
 * flight is `undefined`; the merge answers with an envelope as soon as either
 * one has arrived, see {@link MergeListResult}.
 *
 * @typeParam T - Payload type of the read.
 **/
export type ListMerger<T> = <Onchain extends DataResponse<T> | undefined, Offchain extends DataResponse<T> | undefined>(onchain: Onchain, offchain: Offchain) => MergeListResult<Onchain, Offchain, T>;
/**
 * How a single-entity read combines what the two sources returned. Unlike
 * {@link ListMerger} this stays optional whatever it was given: neither source
 * may have served the entity, and there is nothing to answer with then.
 *
 * @typeParam T - Payload type of the read.
 **/
export type EntityMerger<T> = (onchain: DataResponse<T> | undefined, offchain: DataResponse<T> | undefined) => DataResponse<T> | undefined;
//#endregion
export {};