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";

/**
 * createAccountingPeriod — add an accounting period (会計期間) to a fiscal year.
 *
 * Thin wrapper over the native `createAccountingPeriod`. The company is derived
 * from the fiscal year. Dates must fall within the fiscal year and must not
 * overlap another OPERATING period. The period is created NEVER_OPENED and must
 * be opened before journal entries can post to it.
 */
export default createResolver({
  name: "createAccountingPeriod",
  operation: "mutation",
  input: {
    fiscalYearId: t.string().description("Fiscal year the period belongs to"),
    name: t.string().description("Period name (e.g. 2026-07)"),
    startDate: t.string().description("Start date (YYYY-MM-DD)"),
    endDate: t.string().description("End date (YYYY-MM-DD); must be after the start date"),
    periodType: t.string({ optional: true }).description("OPERATING (default) or ADJUSTMENT"),
  },
  body: async (context) => {
    const ctx = createContext(context);
    const db = getDB("main-db");
    return db
      .transaction()
      .execute(async (trx) => {
        const fiscalYear = await trx
          .selectFrom("FiscalYear")
          .select(["companyId"])
          .where("id", "=", context.input.fiscalYearId)
          .executeTakeFirst();
        if (!fiscalYear) {
          throw new DomainError(`Fiscal year not found: ${context.input.fiscalYearId}`);
        }

        const periodType = context.input.periodType === "ADJUSTMENT" ? "ADJUSTMENT" : "OPERATING";

        const result = await finModulesExport.commands.createAccountingPeriod(
          trx,
          {
            companyId: fiscalYear.companyId,
            fiscalYearId: context.input.fiscalYearId,
            name: context.input.name,
            startDate: new Date(context.input.startDate),
            endDate: new Date(context.input.endDate),
            periodType,
          },
          ctx,
        );

        if (!result.ok) {
          switch (result.error.code) {
            case "FINANCIAL_ACCOUNTING_FISCAL_YEAR_NOT_FOUND":
              throw new DomainError(`Fiscal year not found: ${context.input.fiscalYearId}`);
            case "FINANCIAL_ACCOUNTING_NAME_REQUIRED":
              throw new DomainError("Period name must not be empty.");
            case "FINANCIAL_ACCOUNTING_INVALID_DATE_RANGE":
              throw new DomainError(
                "The period dates must be within the fiscal year and the end date after the start date.",
              );
            case "FINANCIAL_ACCOUNTING_DUPLICATE_PERIOD_DATES":
              throw new DomainError("Another period already covers these exact dates.");
            case "FINANCIAL_ACCOUNTING_OVERLAPPING_PERIOD":
              throw new DomainError("The dates overlap an existing operating period.");
            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.accountingPeriod.id,
          status: result.value.accountingPeriod.status,
        };
      })
      .catch((err: unknown) => {
        if (err instanceof DomainError) throw err;
        throw new Error("Failed to create the accounting period", { cause: err });
      });
  },
  output: t
    .object({
      id: t.string().description("Accounting period ID"),
      status: t.string().description("Period status (NEVER_OPENED)"),
    })
    .description("CreateAccountingPeriod response"),
});