// Persisted settings with a tiny subscribe API. Storage can throw
// (private mode, blocked site data), so every access is guarded.

const KEY = 'picker.settings.v1';

export const DEFAULTS = Object.freeze({
  mode: 'one', // one | pickN | teams | order | elimination
  pickN: 2,
  teams: 2,
  theme: 'neon', // neon | pastel | contrast
  lang: null, // null = follow the browser
  muted: false,
  haptics: true,
  stakeId: null, // preset key, translated at display time
  stakeText: '', // custom text, used when stakeId is null
});

function load() {
  try {
    const raw = localStorage.getItem(KEY);
    if (!raw) return { ...DEFAULTS };
    const parsed = JSON.parse(raw);
    const out = { ...DEFAULTS };
    for (const k of Object.keys(DEFAULTS)) {
      if (k in parsed) out[k] = parsed[k];
    }
    return out;
  } catch {
    return { ...DEFAULTS };
  }
}

function save(s) {
  try {
    localStorage.setItem(KEY, JSON.stringify(s));
  } catch {
    /* storage unavailable: settings just won't persist */
  }
}

export function createSettings() {
  let state = load();
  const listeners = new Set();
  return {
    get: () => state,
    set(patch) {
      state = { ...state, ...patch };
      save(state);
      for (const fn of listeners) fn(state, patch);
    },
    subscribe(fn) {
      listeners.add(fn);
      return () => listeners.delete(fn);
    },
  };
}