import {
  buildPaginatedResult,
  DEFAULT_PAGE_SIZE,
  ok,
  type PaginationInput,
  type ReadonlyDB,
} from "@tailor-platform/erp-kit/core";
import type { DB } from "../generated/kysely-tailordb";

type LeaveRequestOrderByField = "createdAt";

export interface ListLeaveRequestsByWorkerInput extends PaginationInput<LeaveRequestOrderByField> {
  workerId: string;
}

/**
 * Function: listLeaveRequestsByWorker
 * Description: Lists a worker's own leave requests across all statuses, so the
 * worker can see their filing history — pending, approved, rejected,
 * withdrawn, or mid-cancellation. Ordered most-recent first, paginated.
 */
export async function run(db: ReadonlyDB<DB>, input: ListLeaveRequestsByWorkerInput) {
  // Cross-module FK: workerId refers to the workforce module's Worker. No injected
  // getWorker query is wired up for this module yet, so — following createWorker.ts's
  // precedent (modules/workforce/command/createWorker.ts) — we do not invent a fictitious
  // existence check here and simply filter by the given id.

  const limit = input.limit ?? DEFAULT_PAGE_SIZE;
  const offset = input.offset ?? 0;
  const orderBy = input.orderBy ?? "createdAt";
  const orderDirection = input.orderDirection ?? "desc";

  const leaveRequests = await db
    .selectFrom("LeaveRequest")
    .selectAll()
    .where("workerId", "=", input.workerId)
    .orderBy(orderBy, orderDirection)
    .limit(limit + 1)
    .offset(offset)
    .execute();

  return ok(buildPaginatedResult(leaveRequests, limit));
}