import { err, ok, type CommandContext } from "@tailor-platform/erp-kit/core";
import {
  approve,
  deriveSupplyPlans,
  validateOrderItem,
  validateSupplier,
} from "../domain/purchaseOrder";
import type { Transaction } from "../generated/kysely-tailordb";
import { PurchaseOrderNotFoundError } from "../lib/errors.generated";
import type { BusinessPartnerQueries, InventoryCommands, ItemManagementQueries } from "../module";
import {
  createPurchaseItemRepository,
  type PurchaseItemRepository,
} from "../repository/purchaseItemRepository";
import {
  createPurchaseOrderRepository,
  type PurchaseOrderRepository,
} from "../repository/purchaseOrderRepository";

export interface ApprovePurchaseOrderInput {
  id: string;
}

export async function run(
  db: Transaction,
  input: ApprovePurchaseOrderInput,
  ctx: CommandContext,
  supplierAccountQueries: Pick<BusinessPartnerQueries, "getSupplierAccount">,
  itemManagementQueries: Pick<ItemManagementQueries, "getItem">,
  inventoryCommands: Pick<InventoryCommands, "createInventorySupplyPlan">,
  repositoryFactory: (db: Transaction) => PurchaseOrderRepository = createPurchaseOrderRepository,
  purchaseItemRepositoryFactory: (
    db: Transaction,
  ) => PurchaseItemRepository = createPurchaseItemRepository,
) {
  const repository = repositoryFactory(db);
  const order = await repository.findById(input.id, { forUpdate: true });
  if (!order) {
    return err(new PurchaseOrderNotFoundError(input.id));
  }

  const approved = approve(order);
  if (!approved.ok) {
    return approved;
  }

  // The referenced master data may have changed since submission.
  const { account } = (
    await supplierAccountQueries.getSupplierAccount(
      db,
      { supplierAccountId: order.header.supplierAccountId },
      ctx,
    )
  ).value;
  const supplierSnapshot = validateSupplier(
    order.header.supplierAccountId,
    order.header.companyId,
    account,
  );
  if (!supplierSnapshot.ok) {
    return supplierSnapshot;
  }

  const itemIds = [...new Set(order.lines.map((line) => line.itemId))];
  const purchaseItemByItemId = await purchaseItemRepositoryFactory(db).findByItemIds(itemIds);
  for (const itemId of itemIds) {
    const { item } = (await itemManagementQueries.getItem(db, { id: itemId }, ctx)).value;
    const validated = validateOrderItem(itemId, {
      item,
      purchaseItem: purchaseItemByItemId.get(itemId) ?? null,
    });
    if (!validated.ok) {
      return validated;
    }
  }

  await repository.save(approved.value);

  const supplyPlans = deriveSupplyPlans(approved.value);
  if (supplyPlans.length > 0) {
    const syncResult = await inventoryCommands.createInventorySupplyPlan(
      db,
      { sourceType: "PURCHASE_ORDER", sourceId: approved.value.id, supplyPlans },
      ctx,
    );
    if (!syncResult.ok) return syncResult;
  }

  return ok({ purchaseOrderId: approved.value.id });
}