import { WeekdaySet } from './WeekdaySet';
import { MonthlyRecurrencePattern } from './MonthlyRecurrencePattern';
import { RacingDomainValidationError } from '../errors/RacingDomainError';

export type RecurrenceStrategyKind = 'weekly' | 'everyNWeeks' | 'monthlyNthWeekday';

export type WeeklyRecurrence = {
  kind: 'weekly';
  weekdays: WeekdaySet;
};

export type EveryNWeeksRecurrence = {
  kind: 'everyNWeeks';
  intervalWeeks: number;
  weekdays: WeekdaySet;
};

export type MonthlyNthWeekdayRecurrence = {
  kind: 'monthlyNthWeekday';
  monthlyPattern: MonthlyRecurrencePattern;
};

export type RecurrenceStrategy =
  | WeeklyRecurrence
  | EveryNWeeksRecurrence
  | MonthlyNthWeekdayRecurrence;

export class RecurrenceStrategyFactory {
  static weekly(weekdays: WeekdaySet): RecurrenceStrategy {
    return {
      kind: 'weekly',
      weekdays,
    };
  }

  static everyNWeeks(intervalWeeks: number, weekdays: WeekdaySet): RecurrenceStrategy {
    if (!Number.isInteger(intervalWeeks) || intervalWeeks < 1 || intervalWeeks > 12) {
      throw new RacingDomainValidationError(
        'everyNWeeks intervalWeeks must be an integer between 1 and 12',
      );
    }

    return {
      kind: 'everyNWeeks',
      intervalWeeks,
      weekdays,
    };
  }

  static monthlyNthWeekday(monthlyPattern: MonthlyRecurrencePattern): RecurrenceStrategy {
    return {
      kind: 'monthlyNthWeekday',
      monthlyPattern,
    };
  }
}