export interface MetaBranchData {
  id: 'economy' | 'defense' | 'towers'
  name: string
  icon: string
  desc: string
}

export interface MetaUpgradeData {
  id: string
  name: string
  branch: 'economy' | 'defense' | 'towers'
  icon: string
  desc: string
  maxLevel: number
  costs: number[]
}

export declare const UPGRADE_BRANCHES: MetaBranchData[]
export declare const META_UPGRADES: Record<string, MetaUpgradeData>
export declare function calcCrystalsEarned(wave: number, score: number, win: boolean): number