const PREFS_KEY = 'idlegame:prefs:v1';

export type StoryOpenMode = 'auto' | 'choices-only' | 'manual';
export type ActionDetailMode = 'inline' | 'hover' | 'info-button';

export interface GamePrefs {
  storyOpenMode: StoryOpenMode;
  actionDetailMode: ActionDetailMode;
}

const DEFAULTS: GamePrefs = {
  storyOpenMode: 'auto',
  actionDetailMode: 'inline',
};

export function getPrefs(): GamePrefs {
  if (typeof localStorage === 'undefined') return { ...DEFAULTS };
  try {
    const raw = localStorage.getItem(PREFS_KEY);
    if (!raw) return { ...DEFAULTS };
    return { ...DEFAULTS, ...JSON.parse(raw) };
  } catch {
    return { ...DEFAULTS };
  }
}

export function setPrefs(partial: Partial<GamePrefs>): GamePrefs {
  const next = { ...getPrefs(), ...partial };
  if (typeof localStorage !== 'undefined') {
    localStorage.setItem(PREFS_KEY, JSON.stringify(next));
  }
  return next;
}