import { ok, err, type CommandContext } from "@tailor-platform/erp-kit/core";
import { productionOrderLifecycle } from "../db/productionOrder.lifecycle.generated";
import type { Transaction } from "../generated/kysely-tailordb";
import {
  ProductionOrderNotFoundError,
  ProductionOrderNotTechnicallyCompletableError,
  ExecutionExceptionRemainsError,
  PendingMaterialIssueRequestsError,
  CostSummaryNotReadyError,
} from "../lib/errors.generated";

export interface TechnicallyCompleteProductionOrderInput {
  id: string;
}

/**
 * Function: technicallyCompleteProductionOrder
 *
 * Freezes the production order after physical completion and moves the linked
 * manufacturing cost summary into variance review. Marks the point where no
 * more normal execution or rescheduling is expected.
 */
export async function run(
  db: Transaction,
  input: TechnicallyCompleteProductionOrderInput,
  _ctx: CommandContext,
) {
  const { id } = input;

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

  if (!order) {
    return err(new ProductionOrderNotFoundError(id));
  }

  // 2. Validate status
  const nextStatus = productionOrderLifecycle.tryTransition(order.status, "technicallyComplete");
  if (!nextStatus) {
    return err(new ProductionOrderNotTechnicallyCompletableError(id));
  }

  // 3. Check for open execution exceptions (work orders not COMPLETE or CANCELLED)
  const workOrders = await db
    .selectFrom("WorkOrder")
    .selectAll()
    .where("productionOrderId", "=", id)
    .execute();

  const hasExecutionExceptions = workOrders.some(
    (wo) => wo.status === "IN_PROGRESS" || wo.status === "PAUSED",
  );

  if (hasExecutionExceptions) {
    return err(new ExecutionExceptionRemainsError(id));
  }

  // 4. Check for pending material issue requests (work orders still PENDING)
  const hasPendingWork = workOrders.some((wo) => wo.status === "PENDING");

  if (hasPendingWork) {
    return err(new PendingMaterialIssueRequestsError(id));
  }

  // 5. Find and validate cost summary
  const costSummary = await db
    .selectFrom("ManufacturingCostSummary")
    .selectAll()
    .where("productionOrderId", "=", id)
    .forUpdate()
    .executeTakeFirst();

  if (costSummary?.status !== "COLLECTING") {
    return err(new CostSummaryNotReadyError(id));
  }

  // 6. Move cost summary to PENDING_VARIANCE_REVIEW
  await db
    .updateTable("ManufacturingCostSummary")
    .set({
      status: "PENDING_VARIANCE_REVIEW",
    })
    .where("id", "=", costSummary.id)
    .execute();

  // 7. Set order status to TECHNICALLY_COMPLETE
  const techCompleteOrder = await db
    .updateTable("ProductionOrder")
    .set({
      status: nextStatus,
    })
    .where("id", "=", id)
    .returningAll()
    .executeTakeFirstOrThrow();

  return ok({ productionOrder: techCompleteOrder });
}