import * as gatsby from "gatsby";
import * as gqlc from "graphql-compose";
import * as RTE from "fp-ts/ReaderTaskEither";

import { Dependencies } from "../types";

/**
 * Builds a GraphQL union type using the environment's `buildUnionType` function.
 *
 * @param config - Configuration for the union type.
 *
 * @returns Return value of the environment's `buildUnionType` function.
 */
export const buildUnionType = <TSource, TContext>(
	config: gqlc.UnionTypeComposerAsObjectDefinition<TSource, TContext>,
): RTE.ReaderTaskEither<Dependencies, never, gatsby.GatsbyGraphQLUnionType> =>
	RTE.asks((deps) => deps.buildUnionType(config));