import { createContext, DomainError } from "@tailor-platform/erp-kit/app";
import { createResolver, t } from "@tailor-platform/sdk";
import { getDB } from "@/generated/kysely-tailordb";
import { finModulesExport } from "@/modules";

/**
 * createFiscalYear — define a fiscal year (会計年度) for a company.
 *
 * Thin wrapper over the native `createFiscalYear`. The end date must be strictly
 * after the start date and the range must not overlap an existing fiscal year
 * for the same company.
 */
export default createResolver({
  name: "createFiscalYear",
  operation: "mutation",
  input: {
    companyId: t.string().description("Company the fiscal year belongs to"),
    name: t.string().description("Fiscal year name (e.g. FY2026)"),
    startDate: t.string().description("Start date (YYYY-MM-DD)"),
    endDate: t.string().description("End date (YYYY-MM-DD); must be after the start date"),
  },
  body: async (context) => {
    const ctx = createContext(context);
    const db = getDB("main-db");
    return db
      .transaction()
      .execute(async (trx) => {
        const result = await finModulesExport.commands.createFiscalYear(
          trx,
          {
            companyId: context.input.companyId,
            name: context.input.name,
            startDate: new Date(context.input.startDate),
            endDate: new Date(context.input.endDate),
          },
          ctx,
        );

        if (!result.ok) {
          switch (result.error.code) {
            case "FINANCIAL_ACCOUNTING_COMPANY_NOT_FOUND":
              throw new DomainError(`Company not found: ${context.input.companyId}`);
            case "FINANCIAL_ACCOUNTING_NAME_REQUIRED":
              throw new DomainError("Fiscal year name must not be empty.");
            case "FINANCIAL_ACCOUNTING_INVALID_DATE_RANGE":
              throw new DomainError("The end date must be after the start date.");
            case "FINANCIAL_ACCOUNTING_OVERLAPPING_FISCAL_YEAR":
              throw new DomainError(
                "The date range overlaps an existing fiscal year for this company.",
              );
            case "UNAUTHENTICATED":
              throw new DomainError("Authentication is required");
            case "INSUFFICIENT_PERMISSION":
              throw new DomainError("You do not have permission to perform this action");
            default:
              throw result.error satisfies never;
          }
        }

        return {
          id: result.value.fiscalYear.id,
          name: result.value.fiscalYear.name,
        };
      })
      .catch((err: unknown) => {
        if (err instanceof DomainError) throw err;
        throw new Error("Failed to create the fiscal year", { cause: err });
      });
  },
  output: t
    .object({
      id: t.string().description("Fiscal year ID"),
      name: t.string().description("Fiscal year name"),
    })
    .description("CreateFiscalYear response"),
});