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

export interface GetLeaveRequestInput {
  id: string;
}

/**
 * Function: getLeaveRequest
 * Description: Retrieves a single LeaveRequest by id, in any status (PENDING,
 * APPROVED, REJECTED, CANCELLED, CANCEL_PENDING), for detail views and
 * lookups by the requester, an approver, or an administrator.
 */
export async function run(db: ReadonlyDB<DB>, input: GetLeaveRequestInput) {
  const leaveRequest = await db
    .selectFrom("LeaveRequest")
    .selectAll()
    .where("id", "=", input.id)
    .executeTakeFirst();

  if (!leaveRequest) {
    return err(new LeaveRequestNotFoundError(input.id));
  }

  return ok({ leaveRequest });
}