import { ok, err, type CommandContext } from "@tailor-platform/erp-kit/core";
import { workOrderLifecycle } from "../db/workOrder.lifecycle.generated";
import type { Transaction } from "../generated/kysely-tailordb";
import {
  WorkOrderNotFoundError,
  WorkOrderNotResumableError,
  ParentOrderNotExecutableError,
} from "../lib/errors.generated";

const EXECUTABLE_ORDER_STATUSES = ["RELEASED", "IN_PROGRESS"] as const;

export interface ResumeWorkOrderInput {
  id: string;
}

/**
 * Function: resumeWorkOrder
 *
 * Restarts a paused work order without losing the accumulated execution
 * history recorded before the interruption. Clears the pause reason.
 */
export async function run(db: Transaction, input: ResumeWorkOrderInput, _ctx: CommandContext) {
  const { id } = input;

  // 1. Fetch work order with lock
  const workOrder = await db
    .selectFrom("WorkOrder")
    .selectAll()
    .where("id", "=", id)
    .forUpdate()
    .executeTakeFirst();

  if (!workOrder) {
    return err(new WorkOrderNotFoundError(id));
  }

  // 2. Validate status is PAUSED
  const nextStatus = workOrderLifecycle.tryTransition(workOrder.status, "resume");
  if (!nextStatus) {
    return err(new WorkOrderNotResumableError(id));
  }

  // 3. Check parent production order is still execution-capable
  const parentOrder = await db
    .selectFrom("ProductionOrder")
    .selectAll()
    .where("id", "=", workOrder.productionOrderId)
    .forUpdate()
    .executeTakeFirst();

  if (
    !parentOrder ||
    !EXECUTABLE_ORDER_STATUSES.includes(
      parentOrder.status as (typeof EXECUTABLE_ORDER_STATUSES)[number],
    )
  ) {
    return err(new ParentOrderNotExecutableError(id));
  }

  // 4. Record resume event and set IN_PROGRESS, clear pause reason
  const now = new Date();

  const updatedWorkOrder = await db
    .updateTable("WorkOrder")
    .set({
      status: nextStatus,
      pauseReason: null,
    })
    .where("id", "=", id)
    .returningAll()
    .executeTakeFirstOrThrow();

  // 5. Create RESUMED execution event
  await db
    .insertInto("WorkOrderExecutionEvent")
    .values({
      workOrderId: id,
      eventType: "RESUMED",
      timestamp: now,
      quantity: null,
      timeValue: null,
      scrapValue: null,
      notes: null,
    })
    .execute();

  return ok({ workOrder: updatedWorkOrder });
}