import { err, ok, type ReadonlyDB } from "@tailor-platform/erp-kit/core";
import type { DB } from "../generated/kysely-tailordb";
import { CalculatedBlockNotFoundError } from "../lib/errors.generated";

export interface GetCalculatedBlockInput {
  id: string;
}

/**
 * Function: getCalculatedBlock
 * Description: Retrieves a single CalculatedTimeBlock by its id. Used when a
 * caller already has a specific calculated block id — for example when
 * following sourceReportedBlockIds/calculationTagKeys traceability links back
 * from a payroll or Article-36 agreement read, or when drilling into one block from a list
 * result.
 */
export async function run(db: ReadonlyDB<DB>, input: GetCalculatedBlockInput) {
  const calculatedTimeBlock = await db
    .selectFrom("CalculatedTimeBlock")
    .selectAll()
    .where("id", "=", input.id)
    .executeTakeFirst();

  if (!calculatedTimeBlock) {
    return err(new CalculatedBlockNotFoundError(input.id));
  }

  return ok({ calculatedTimeBlock });
}