import type { Package } from '../../api';

export function classifyPackageTier(price: number, activePrice: number | null): {
  isUpgrade: boolean;
  isDowngrade: boolean;
} {
  if (activePrice === null) {
    return { isUpgrade: false, isDowngrade: false };
  }

  return {
    isUpgrade: price > activePrice,
    isDowngrade: price < activePrice,
  };
}

export function selectRecommendedPackageId(
  packages: Package[],
  feature: string | null,
  activePrice: number | null
): number | null {
  if (!feature) {
    return null;
  }

  const candidates = packages.filter((pkg) => pkg.features?.[feature]);
  if (candidates.length === 0) {
    return null;
  }

  const upgradeCandidates =
    activePrice === null
      ? candidates
      : candidates.filter((pkg) => pkg.price > activePrice);

  const pool = upgradeCandidates.length ? upgradeCandidates : candidates;
  const sorted = [...pool].sort((a, b) => a.price - b.price);

  return sorted[0]?.id ?? null;
}