/**
 * gameState.js — Game progress persistence
 * Tracks completed levels, stars earned, unlocks, and saved patches per level
 */

const STORAGE_KEY = 'synthquest-progress';
const PATCHES_KEY = 'synthquest-patches';

const defaultProgress = {
  currentWorld: 'w1',
  completedLevels: {},  // { levelId: { stars: 3 } }
  unlockedWorlds: ['w1'],
  totalStars: 0,
};

let _progress = null;
let _patches = null; // { levelId: { modules, connections } }

export function loadProgress() {
  if (_progress) return _progress;
  try {
    const raw = localStorage.getItem(STORAGE_KEY);
    _progress = raw ? { ...defaultProgress, ...JSON.parse(raw) } : { ...defaultProgress };
  } catch {
    _progress = { ...defaultProgress };
  }
  return _progress;
}

export function saveProgress() {
  if (!_progress) return;
  _progress.totalStars = Object.values(_progress.completedLevels)
    .reduce((sum, l) => sum + (l.stars || 0), 0);
  try {
    localStorage.setItem(STORAGE_KEY, JSON.stringify(_progress));
  } catch {}
}

export function completeLevel(levelId, stars) {
  const p = loadProgress();
  const existing = p.completedLevels[levelId];
  if (!existing || stars > existing.stars) {
    p.completedLevels[levelId] = { stars, completedAt: Date.now() };
  }
  saveProgress();
}

export function getLevelProgress(levelId) {
  const p = loadProgress();
  return p.completedLevels[levelId] || null;
}

export function isLevelUnlocked(levelId, worldLevels) {
  const p = loadProgress();
  const idx = worldLevels.findIndex(l => l.id === levelId);
  if (idx === 0) return true;
  const prevId = worldLevels[idx - 1]?.id;
  return prevId && p.completedLevels[prevId]?.stars >= 1;
}

export function resetProgress() {
  _progress = { ...defaultProgress };
  _patches = {};
  _hints = {};
  saveProgress();
  savePatches();
  saveHints();
}

// ==================== Level patch persistence ====================

function loadPatches() {
  if (_patches) return _patches;
  try {
    const raw = localStorage.getItem(PATCHES_KEY);
    _patches = raw ? JSON.parse(raw) : {};
  } catch {
    _patches = {};
  }
  return _patches;
}

function savePatches() {
  if (!_patches) return;
  try {
    localStorage.setItem(PATCHES_KEY, JSON.stringify(_patches));
  } catch {}
}

export function saveLevelPatch(levelId, modules, connections) {
  const patches = loadPatches();
  patches[levelId] = {
    modules: modules.map(m => ({ id: m.id, type: m.type, x: m.x, y: m.y, params: { ...m.params } })),
    connections: connections.map(c => ({ ...c })),
    savedAt: Date.now(),
  };
  savePatches();
}

export function getLevelPatch(levelId) {
  const patches = loadPatches();
  return patches[levelId] || null;
}

export function clearLevelPatch(levelId) {
  const patches = loadPatches();
  delete patches[levelId];
  savePatches();
}

// ==================== Hint tracking (persisted, no cheating!) ====================

const HINTS_KEY = 'synthquest-hints';
let _hints = null; // { levelId: true }

function loadHints() {
  if (_hints) return _hints;
  try {
    const raw = localStorage.getItem(HINTS_KEY);
    _hints = raw ? JSON.parse(raw) : {};
  } catch {
    _hints = {};
  }
  return _hints;
}

function saveHints() {
  if (!_hints) return;
  try {
    localStorage.setItem(HINTS_KEY, JSON.stringify(_hints));
  } catch {}
}

export function markHintUsed(levelId) {
  const hints = loadHints();
  hints[levelId] = true;
  saveHints();
}

export function wasHintUsed(levelId) {
  const hints = loadHints();
  return !!hints[levelId];
}

export function clearHintForLevel(levelId) {
  const hints = loadHints();
  delete hints[levelId];
  saveHints();
}