import * as gqlc from "graphql-compose";
import * as prismicT from "@prismicio/types";
import * as RTE from "fp-ts/ReaderTaskEither";
import * as R from "fp-ts/Record";
import * as A from "fp-ts/Array";
import { pipe } from "fp-ts/function";

import { mapRecordIndices } from "./mapRecordIndices";
import { toFieldConfig } from "./toFieldConfig";

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

/**
 * Builds a `graphql-compose`-compatible field config map by calling
 * `lib/toFieldConfig` for each field.
 *
 * Field names are transformed using the environment's plugin options's
 * `transformFieldName` function.
 *
 * @param path - Field path leading to `fieldSchemas`'s location.
 * @param fieldSchemas - Record of Prismic custom type schema fields.
 *
 * @returns Field config map including `fieldSchemas`'s fields.
 */
export const buildFieldConfigMap = (
	path: string[],
	fieldSchemas: Record<string, prismicT.CustomTypeModelField>,
): RTE.ReaderTaskEither<
	Dependencies,
	Error,
	gqlc.ObjectTypeComposerFieldConfigMapDefinition<unknown, unknown>
> =>
	pipe(
		RTE.ask<Dependencies>(),
		RTE.chain((deps) =>
			pipe(
				fieldSchemas,
				mapRecordIndices(deps.transformFieldName),
				R.mapWithIndex((name, schema) =>
					toFieldConfig(pipe(path, A.append(name)), schema),
				),
				R.sequence(RTE.ApplicativeSeq),
			),
		),
		RTE.map(
			R.filter((fieldConfig): fieldConfig is NonNullable<typeof fieldConfig> =>
				Boolean(fieldConfig),
			),
		),
	);