// Achievements: permanent small bonuses for milestones. Each one reads a
// single statistic, so adding one is a line in data/achievements.json (plus
// its title in the core locale files).

export function statValue(state, stat) {
  switch (stat) {
    case 'lifetimeProduced':
      return state.lifetimeProduced;
    case 'generatorsOwned':
      return Object.values(state.generators).reduce((sum, n) => sum + n, 0);
    case 'upgradesOwned':
      return state.upgrades.length;
    case 'researchOwned':
      return state.research.length;
    case 'prestiges':
      return state.legacy.prestiges;
    case 'chips':
      return state.chips;
    default:
      return state.stats[stat] ?? 0; // investProfit, gambleWins, contractsDone, eventsClaimed...
  }
}

/** Grant every achievement whose condition is now met. Returns the new ids. */
export function checkAchievements(state, ctx) {
  const granted = [];
  for (const a of ctx.achievements) {
    if (state.achievements.includes(a.id)) continue;
    if (statValue(state, a.condition.stat) >= a.condition.min) {
      state.achievements.push(a.id);
      granted.push(a.id);
    }
  }
  return granted;
}