/** One pier as the 재료표 scope sees it. */
export interface QuantityPier {
  name: string;
  hasModel: boolean;
}

/**
 * The piers the ④ 재료표 shows: every pier with a model when 전체 is on, otherwise only the chosen pier
 * (교각 목록에서 고른 교각). A chosen pier without a model shows nothing.
 */
export function quantityTargetNames(piers: QuantityPier[], all: boolean, active: string | null): string[] {
  if (all) return piers.filter((p) => p.hasModel).map((p) => p.name);
  return piers.filter((p) => p.hasModel && p.name === active).map((p) => p.name);
}