import { err, ok } from "@tailor-platform/erp-kit/core";
import {
  CompanyNotFoundError,
  NameRequiredError,
  InvalidDateRangeError,
  DatesImmutableError,
  HasAssociatedPeriodsError,
} from "../lib/errors.generated";

export interface FiscalYear {
  readonly id: string;
  readonly companyId: string;
  readonly name: string;
  readonly startDate: Date;
  readonly endDate: Date;
  readonly yearEndCloseExecuted: boolean;
}
export interface CreateFiscalYearInput {
  companyId: string;
  name: string;
  startDate: Date;
  endDate: Date;
}

export interface UpdateFiscalYearInput {
  id: string;
  yearName?: string;
  startDate?: Date;
  endDate?: Date;
}

export function create<CF extends Record<string, unknown>>(
  input: CreateFiscalYearInput & CF,
  refs: { companyExists: boolean },
) {
  if (!refs.companyExists) return err(new CompanyNotFoundError(input.companyId));
  if (!input.name || input.name.trim() === "") return err(new NameRequiredError(input.companyId));
  if (input.startDate >= input.endDate) return err(new InvalidDateRangeError(input.companyId));
  const { companyId, name, startDate, endDate, ...customFields } = input;
  return ok({ ...customFields, companyId, name, startDate, endDate, yearEndCloseExecuted: false });
}

export function update<CF extends Record<string, unknown>>(
  existing: FiscalYear,
  input: UpdateFiscalYearInput & Partial<CF>,
  refs: { periodsExist: boolean },
) {
  const { id, yearName, startDate, endDate, ...customFields } = input;
  const validName = validateNameChange(id, yearName);
  if (!validName.ok) return validName;
  if (startDate !== undefined || endDate !== undefined) {
    if (refs.periodsExist) return err(new DatesImmutableError(id));
    if ((startDate ?? existing.startDate) >= (endDate ?? existing.endDate))
      return err(new InvalidDateRangeError(id));
  }
  return ok({
    ...customFields,
    ...(yearName !== undefined ? { name: yearName } : {}),
    ...(startDate !== undefined ? { startDate } : {}),
    ...(endDate !== undefined ? { endDate } : {}),
  });
}

export function checkDeletable(id: string, hasPeriods: boolean) {
  return hasPeriods ? err(new HasAssociatedPeriodsError(id)) : ok({});
}

export function validateNameChange(id: string, name: string | undefined) {
  return name !== undefined && name.trim() === "" ? err(new NameRequiredError(id)) : ok({});
}