import type { Beneficiary } from '@/types';
import { isSubscriptionActive, isSubscriptionExpiringSoon } from '@/services/subscription';

export type BeneficiarySetupState =
  | 'loading'
  | 'awaiting_equipment'
  | 'no_devices'
  | 'no_subscription'
  | 'ready';

export const hasBeneficiaryDevices = (beneficiary: Beneficiary): boolean => {
  return Boolean(
    beneficiary.hasDevices ||
    (beneficiary.devices && beneficiary.devices.length > 0) ||
    beneficiary.device_id
  );
};

export const hasActiveSubscription = (beneficiary: Beneficiary): boolean => {
  return isSubscriptionActive(beneficiary.subscription);
};

export const getBeneficiarySetupState = (
  beneficiary: Beneficiary | null,
  isLoading: boolean
): BeneficiarySetupState => {
  if (isLoading || !beneficiary) return 'loading';

  const hasDevices = hasBeneficiaryDevices(beneficiary);
  const equipmentStatus = beneficiary.equipmentStatus;

  // Waterfall priority:
  // 1. First check devices (highest priority)
  if (!hasDevices) {
    // Equipment is on the way - waiting for delivery
    if (equipmentStatus && ['ordered', 'shipped', 'delivered'].includes(equipmentStatus)) {
      return 'awaiting_equipment';
    }
    // No devices and no order - need to buy equipment
    return 'no_devices';
  }

  // 2. Then check subscription (only if devices exist)
  if (!isSubscriptionActive(beneficiary.subscription)) {
    return 'no_subscription';
  }

  // 3. All good → ready
  return 'ready';
};

export const shouldShowSubscriptionWarning = (beneficiary: Beneficiary | null): boolean => {
  return beneficiary ? isSubscriptionExpiringSoon(beneficiary.subscription) : false;
};

export type BeneficiaryRouteKey = 'index' | 'subscription' | 'equipment' | 'share';

export const getDefaultBeneficiaryRouteKey = (
  beneficiary: Beneficiary | null,
  isLoading: boolean
): BeneficiaryRouteKey | null => {
  const state = getBeneficiarySetupState(beneficiary, isLoading);
  if (state === 'loading') return null;
  if (state === 'no_subscription') return 'subscription';
  return 'index';
};

export const getRedirectRouteKey = (
  currentRouteKey: BeneficiaryRouteKey,
  beneficiary: Beneficiary | null,
  isLoading: boolean
): BeneficiaryRouteKey | null => {
  const state = getBeneficiarySetupState(beneficiary, isLoading);
  if (state === 'loading') return null;

  if (currentRouteKey === 'index' && state === 'no_subscription') {
    return 'subscription';
  }

  if (currentRouteKey === 'subscription' && state !== 'no_subscription') {
    return 'index';
  }

  return null;
};