/* Neon Rampage — DOM UI: menus, shop, settings, leaderboard, overlays. */
(function () {
  'use strict';
  var US = (window.US = window.US || {});
  var $ = function (id) { return document.getElementById(id); };

  var reviveTimer = null;

  function show(el) { el.classList.remove('hidden'); }
  function hide(el) { el.classList.add('hidden'); }

  function toast(msg) {
    var t = $('toast');
    t.textContent = msg;
    show(t);
    clearTimeout(toast._h);
    toast._h = setTimeout(function () { hide(t); }, 2200);
  }

  /* ---------------- screens ---------------- */
  var SCREENS = ['menu', 'shop', 'settings', 'rank', 'howto', 'arena-setup', 'quests', 'bestiary'];

  function L(o) { var sv = US.save.get(); return (o && (o[vi0()] || o.en)) || ''; }
  function vi0() { return US.save.get().lang === 'vi' ? 'vi' : 'en'; }

  function showScreen(name) {
    SCREENS.forEach(function (s) {
      var el = $('screen-' + s);
      if (el) (s === name ? show : hide)(el);
    });
    $('hud-root').classList.toggle('in-game', !name);
    refreshMenuStats();
  }
  US.uiShowScreen = showScreen;

  function refreshMenuStats() {
    var s = US.save.get();
    $('menu-coins').textContent = '$' + US.util.fmt(s.coins);
    if ($('menu-gems')) $('menu-gems').textContent = '🔥 ' + (s.gems | 0);
    if ($('dot-upgrades')) {
      var canUp = Object.keys(US.UPGRADES || {}).some(function (k) {
        var d = US.UPGRADES[k];
        return (s.upgrades[k] | 0) < d.max && s.coins >= upCost(d, s.upgrades[k] | 0);
      });
      $('dot-upgrades').classList.toggle('hidden', !canUp);
    }
    $('menu-best').textContent =
      US.i18n.t('menu.bestScore') + ': ' + US.util.fmt(s.bestScore) +
      '   ·   ' + US.i18n.t('menu.bestWave') + ': ' + s.bestWave;
  }

  /* ---------------- shop ---------------- */
  var shopTab = 'weapons';

  /* ---- live-drawn icons: reuse the game's own painters as thumbnails --- */
  function makePreview(w, h, drawFn) {
    var wrap = document.createElement('div');
    wrap.className = 'item-prev';
    var cv = document.createElement('canvas');
    cv.width = w; cv.height = h;
    cv.style.width = w + 'px'; cv.style.height = h + 'px';
    if (drawFn) {
      var c2 = cv.getContext('2d');
      try {
        drawFn(c2, w, h);
      } catch (e) {
        // never leave a silent empty plate: show fallback + log the truth
        console.warn('[icon] painter failed:', e && e.message, e);
        c2.fillStyle = '#ffb938';
        c2.font = '30px system-ui';
        c2.textAlign = 'center'; c2.textBaseline = 'middle';
        c2.fillText('🎨', w / 2, h / 2);
      }
    }
    wrap.appendChild(cv);
    return wrap;
  }

  var UP_ICON = { hp: '❤️', dmg: '🦷', speed: '💨', ult: '☀️', coin: '🧿', bombs: '💣' };

  // hero bust: top-down but angled up so it reads like a portrait
  function drawHeroIcon(c2, w, h, bodyCol, trimCol, kind) {
    c2.save();
    c2.translate(w / 2 - 46 * 1.25, h / 2 - 30 * 1.25);
    c2.scale(1.25, 1.25);
    US.art.drawHuman(c2, {
      x: 46, y: 30, radius: 14, aim: -Math.PI / 2,
      walkPhase: 0, moving: false,
      color: bodyCol || '#e04b3a',
      body: bodyCol || '#e04b3a', trim: trimCol || '#e8dcc4',
      weaponKind: kind || 'slingshot',
      hurtT: 0, fireT: 0, torch: false, scale: 1.3, seedF: 3
    }, 1);
    c2.restore();
  }

  function drawWeaponIcon(c2, w, h, kind) {
    c2.save();
    c2.translate(12, h / 2);
    c2.scale(1.9, 1.9);
    US.art.drawHeldWeapon(c2, kind, 0);
    c2.restore();
  }

  var BEST_DRAW = {
    grunt:      { fn: 'drawRaptor',       r: 15 },
    runner:     { fn: 'drawRaptor',       r: 11 },
    spitter:    { fn: 'drawDilo',         r: 14 },
    tank:       { fn: 'drawTriceratops',  r: 21 },
    stego:      { fn: 'drawStego',        r: 19 },
    pachy:      { fn: 'drawPachy',        r: 14 },
    splitter:   { fn: 'drawPtero',        r: 17, opt: false },
    mini:       { fn: 'drawPtero',        r: 11, opt: true },
    eliteGrunt: { fn: 'drawRaptor',       r: 18 },
    bruiser:    { fn: 'drawRex',          r: 25 },
    artillery:  { fn: 'drawSpino',        r: 25 },
    hydra:      { fn: 'drawGiga',         r: 25 }
  };

  function drawBeastIcon(c2, w, h, speciesId, locked) {
    var spec = BEST_DRAW[speciesId];
    if (!spec) return;
    var def = (US.ENEMIES && (US.ENEMIES[speciesId])) ||
              (speciesId === 'bruiser' ? (US.BOSSES && US.BOSSES.bruiser) : null) || {};
    var col = def.color || '#5f8f3e';
    var ent = {
      x: w / 2, y: h / 2 + 4, radius: spec.r,
      face: -Math.PI / 2, color: col, hitFlash: 0,
      seed: 3, walkPhase: 0, dashing: 0, dashCd: 9,
      shootCd: 1, charging: false, spawnAnim: 0
    };
    c2.save();
    if (locked) c2.globalAlpha = 0.22;
    var fn2 = US.art[spec.fn];
    if (spec.opt === undefined) fn2(c2, ent, 1.23);
    else fn2(c2, ent, 1.23, spec.opt);
    c2.restore();
    if (locked) {
      c2.fillStyle = 'rgba(243,231,207,0.75)';
      c2.font = 'bold 26px system-ui';
      c2.textAlign = 'center'; c2.textBaseline = 'middle';
      c2.fillText('?', w / 2, h / 2);
    }
  }

  function renderShop() {
    var s = US.save.get();
    $('shop-coins').textContent = '$' + US.util.fmt(s.coins);
    if ($('shop-gems')) $('shop-gems').textContent = '🔥 ' + (s.gems | 0);
    ['weapons', 'heroes', 'skins', 'upgrades'].forEach(function (t) {
      $('tab-' + t).classList.toggle('active', t === shopTab);
    });
    var grid = $('shop-grid');
    grid.innerHTML = '';
    var list, ownArr, equipKey;

    if (shopTab === 'upgrades') { renderUpgrades(grid); return; }
    if (shopTab === 'weapons') { list = US.WEAPONS; ownArr = s.weapons; equipKey = 'weapon'; }
    else if (shopTab === 'heroes') { list = US.HEROES; ownArr = s.heroes; equipKey = 'hero'; }
    else { list = US.SKINS; ownArr = s.skins; equipKey = 'skin'; }

    Object.keys(list).forEach(function (id) {
      var it = list[id];
      var owned = ownArr.indexOf(id) >= 0;
      var equipped = s[equipKey] === id;
      var card = document.createElement('div');
      card.className = 'item' + (equipped ? ' equipped' : '');

      // live-drawn thumbnail
      if (shopTab === 'weapons') {
        card.appendChild(makePreview(96, 50, function (c2, w2, h2) {
          drawWeaponIcon(c2, w2, h2, it.kind);
        }));
      } else if (shopTab === 'heroes') {
        card.appendChild(makePreview(96, 58, function (c2, w2, h2) {
          drawHeroIcon(c2, w2, h2, it.tint || it.body || '#e04b3a', '#e8dcc4', 'slingshot');
        }));
      } else if (shopTab === 'skins') {
        card.appendChild(makePreview(96, 58, function (c2, w2, h2) {
          // bold colour disc so every paint job is unmistakable
          c2.fillStyle = it.body || '#e04b3a';
          c2.beginPath();
          c2.arc(w2 / 2, h2 / 2 + 2, 21, 0, Math.PI * 2);
          c2.fill();
          c2.strokeStyle = 'rgba(0,0,0,0.4)';
          c2.lineWidth = 2;
          c2.stroke();
          drawHeroIcon(c2, w2, h2, it.body, it.trim, (US.WEAPONS[sv.weapon] || {}).kind);
          if (it.premium) {
            c2.strokeStyle = 'rgba(255,210,74,0.8)';
            c2.lineWidth = 2;
            c2.strokeRect(1.5, 1.5, w2 - 3, h2 - 3);
          }
          // ground truth: sample what actually landed on the canvas
          try {
            var px3 = c2.getImageData(Math.round(w2 / 2), Math.round(h2 / 2) + 16, 1, 1).data;
            console.log('[icon]', it.name, 'want', it.body,
              'got rgb(' + px3[0] + ',' + px3[1] + ',' + px3[2] + ')');
          } catch (e3) { /* tainted ctx: ignore */ }
        }));
      } else if (shopTab === 'upgrades') {
        var up = document.createElement('div');
        up.className = 'item-prev up-icon';
        up.textContent = UP_ICON[it.id] || '💪';
        card.appendChild(up);
      }

      var h = document.createElement('div');
      h.className = 'item-name';
      h.textContent = it.premium ? (L(it) || it.name) : it.name;
      card.appendChild(h);

      var desc = document.createElement('div');
      desc.className = 'item-desc';
      if (shopTab === 'weapons') {
        desc.textContent = 'DMG ' + it.dmg + ' · ROF ' + it.rof + '/s' +
          (it.pellets > 1 ? ' · ×' + it.pellets : '') + (it.pierce ? ' · PIERCE' : '') + (it.aoe ? ' · AoE' : '');
      } else if (shopTab === 'heroes') {
        desc.textContent = US.i18n.t('hero.statHp') + ' ' + it.hp + ' · ' +
          US.i18n.t('hero.statSpeed') + ' ' + it.speed + ' · ' + it.talent;
      } else if (it.premium) {
        desc.textContent = L(it) || 'Legendary paint';
        card.classList.add('premium');
      } else {
        desc.textContent = it.name === 'Default' ? 'Standard issue' : 'Chromatic skin';
      }
      card.appendChild(desc);

      var btn = document.createElement('button');
      btn.className = 'btn';
      if (equipped) {
        btn.textContent = US.i18n.t('shop.equipped');
        btn.disabled = true;
      } else if (owned) {
        btn.textContent = US.i18n.t('shop.equip');
        btn.onclick = function () {
          US.audio.sfx('ui');
          US.save.equip(equipKey, id);
          renderShop();
        };
      } else {
        if (it.premium) {
          btn.innerHTML = '🔥 ' + it.gems;
          btn.onclick = function () {
            if (!US.save.spendGems(it.gems)) { toast(L({ en: 'Not enough flames!', vi: 'Không đủ ngọn lửa!' })); return; }
            US.save.ownSkin(id);
            US.save.equip(equipKey, id);
            US.audio.sfx('buy');
            toast(US.i18n.t('shop.bought'));
            renderShop();
          };
        } else {
        btn.textContent = US.i18n.t('shop.buy') + ' — $' + it.price;
        btn.onclick = function () {
          var cur = US.save.get();
          if (cur.coins < it.price) { toast(US.i18n.t('toast.notEnough')); return; }
          US.save.addCoins(-it.price);
          if (shopTab === 'weapons') US.save.ownWeapon(id);
          else if (shopTab === 'heroes') US.save.ownHero(id);
          else US.save.ownSkin(id);
          US.save.equip(equipKey, id);
          US.audio.sfx('buy');
          toast(US.i18n.t('shop.bought'));
          renderShop();
        };
        }
      }
      card.appendChild(btn);
      grid.appendChild(card);
    });

    // spare bombs row
    var bombRow = $('shop-bombs');
    bombRow.innerHTML = '';
    var bl = document.createElement('span');
    bl.className = 'bomb-label';
    bl.textContent = '💣 ' + US.i18n.t('shop.bombs') + ': ' + (s.bombs | 0);
    var bb = document.createElement('button');
    bb.className = 'btn';
    bb.textContent = US.i18n.t('shop.buy') + ' — $50';
    bb.onclick = function () {
      var cur = US.save.get();
      if (cur.coins < 50) { toast(US.i18n.t('toast.notEnough')); return; }
      US.save.addCoins(-50);
      cur.bombs = (cur.bombs | 0) + 1;
      US.save.save();
      US.audio.sfx('buy');
      renderShop();
    };
    bombRow.appendChild(bl);
    bombRow.appendChild(bb);
  }

  /* ---------------- settings ---------------- */
  function bindSettings() {
    var s = US.save.get();
    var langSel = $('set-lang');
    langSel.value = s.lang;
    langSel.onchange = function () {
      US.save.get().lang = langSel.value;
      US.save.save();
      US.i18n.setLang(langSel.value);
      US.i18n.apply();
    };
    $('set-sfx').value = s.settings.sfx * 100;
    $('set-music').value = s.settings.music * 100;
    $('set-autoaim').checked = !!s.settings.autoAim;
    $('set-autofire').checked = !!s.settings.autofire;
    $('set-onehit').checked = !!s.settings.onehit;
    $('set-shake').checked = !!s.settings.shake;
    $('set-name').value = s.name;

    $('set-sfx').oninput = function () { US.save.get().settings.sfx = this.value / 100; US.audio.setVolumes(); US.save.save(); };
    $('set-music').oninput = function () { US.save.get().settings.music = this.value / 100; US.audio.setVolumes(); US.save.save(); };
    if ($('set-autoaim')) $('set-autoaim').onchange = function () { US.save.get().settings.autoAim = this.checked; US.save.save(); };
    $('set-autofire').onchange = function () { US.save.get().settings.autofire = this.checked; US.save.save(); };
    $('set-onehit').onchange = function () { US.save.get().settings.onehit = this.checked; US.save.save(); };
    $('set-shake').onchange = function () { US.save.get().settings.shake = this.checked; US.save.save(); };
    if ($('set-shakeamt')) {
      var sa = $('set-shakeamt');
      sa.value = Math.round((US.save.get().settings.shakeAmt == null ? 1 : US.save.get().settings.shakeAmt) * 100);
      if ($('val-shakeamt')) $('val-shakeamt').textContent = sa.value + '%';
      sa.oninput = function () {
        US.save.get().settings.shakeAmt = this.value / 100;
        US.save.save();
        if ($('val-shakeamt')) $('val-shakeamt').textContent = this.value + '%';
      };
    }
    if ($('set-quality')) {
      $('set-quality').value = US.save.get().settings.quality || 'high';
      $('set-quality').onchange = function () {
        US.save.get().settings.quality = this.value;
        US.save.save();
      };
    }
    $('set-name').onchange = function () {
      US.save.get().name = (this.value || 'Rookie').slice(0, 16);
      US.save.save();
      toast(US.i18n.t('toast.saved'));
    };
    $('set-reset').onclick = function () {
      if (confirm(US.i18n.t('set.resetConfirm'))) {
        US.save.reset();
        location.reload();
      }
    };
  }

  /* ---------------- leaderboard ---------------- */
  function renderRank() {
    var s = US.save.get();
    var box = $('rank-body');
    box.innerHTML = '';
    if (!s.board.length) {
      var d = document.createElement('div');
      d.className = 'empty';
      d.textContent = US.i18n.t('rank.empty');
      box.appendChild(d);
      return;
    }
    s.board.forEach(function (row, i) {
      var r = document.createElement('div');
      r.className = 'rank-row' + (i === 0 ? ' gold' : '');
      [('#' + (i + 1)), row.name, US.util.fmt(row.score), String(row.wave)].forEach(function (cell) {
        var c = document.createElement('span');
        c.textContent = cell;
        r.appendChild(c);
      });
      box.appendChild(r);
    });
  }

  /* ---------------- card pick ---------------- */
  function showCardPick(cards, onPick) {
    var ov = $('overlay-cards');
    var wrap = $('card-row');
    wrap.innerHTML = '';
    $('card-hint').textContent = US.i18n.t('card.pickHint');
    cards.forEach(function (c) {
      var el = document.createElement('div');
      el.className = 'card rarity-' + c.rarity;
      var rc = document.createElement('span');
      rc.className = 'card-rarity';
      rc.textContent = US.i18n.t('card.rarity' + c.rarity.charAt(0).toUpperCase() + c.rarity.slice(1));
      var ic = document.createElement('div');
      ic.className = 'card-icon';
      ic.textContent = c.icon;
      var tt = document.createElement('div');
      tt.className = 'card-title';
      tt.textContent = c.title;
      var dd = document.createElement('div');
      dd.className = 'card-desc';
      dd.textContent = c.desc;
      el.appendChild(rc); el.appendChild(ic); el.appendChild(tt); el.appendChild(dd);
      el.onclick = function () {
        US.audio.sfx('card');
        hide(ov);
        onPick(c);
      };
      wrap.appendChild(el);
    });
    show(ov);
  }

  /* ---------------- pause / gameover / revive ---------------- */
  function showPause() { show($('overlay-pause')); }
  function hidePause() { hide($('overlay-pause')); }

  function gameOver(stats, mode) {
    $('over-title').textContent = US.i18n.t('over.title');
    $('over-record').classList.toggle('hidden', !stats.record);
    $('ov-score').textContent = US.util.fmt(stats.score);
    $('ov-wave').textContent = mode === 'campaign' ? stats.wave : '—';
    $('ov-kills').textContent = stats.kills;
    $('ov-combo').textContent = '×' + stats.bestCombo;
    $('ov-coins').textContent = '+$' + stats.coins;
    setupAdButton(stats.coins | 0);
    show($('overlay-over'));
  }

  function arenaOver(winner, g) {
    $('over-title').textContent = winner.player ? US.i18n.t('over.win') : 'DEFEAT';
    $('over-record').classList.add('hidden');
    $('ov-score').textContent = g.kills + ' / ' + g.targetKills;
    $('ov-wave').textContent = '—';
    $('ov-kills').textContent = g.kills;
    $('ov-combo').textContent = '×' + (g.bestCombo || 0);
    $('ov-coins').textContent = '+$' + g.runCoins;
    show($('overlay-over'));
  }

  function showRevive(cost, seconds) {
    $('revive-cost').textContent = '-$' + cost;
    var left = seconds;
    $('revive-count').textContent = left;
    show($('overlay-revive'));
    clearInterval(reviveTimer);
    reviveTimer = setInterval(function () {
      left--;
      $('revive-count').textContent = Math.max(0, left);
      if (left <= 0) US.game.declineRevive();
    }, 1000);
  }
  function hideRevive() {
    clearInterval(reviveTimer);
    hide($('overlay-revive'));
  }


  /* ---------------- permanent upgrades tab ---------------- */
  function upCost(def, lv) { return def.base * (lv + 1); }

  function renderUpgrades(grid) {
    var sv = US.save.get();
    var bombRow = $('shop-bombs');
    if (bombRow) bombRow.innerHTML = '';
    Object.keys(US.UPGRADES).forEach(function (id) {
      var d = US.UPGRADES[id];
      var lv = sv.upgrades[id] | 0;
      var maxed = lv >= d.max;
      var cost = upCost(d, lv);

      var card = document.createElement('div');
      card.className = 'item upgrade' + (maxed ? ' equipped' : '');

      var h = document.createElement('div');
      h.className = 'item-name';
      h.textContent = L(d);
      card.appendChild(h);

      var pips = document.createElement('div');
      pips.className = 'pips';
      for (var i = 0; i < d.max; i++) {
        var pip = document.createElement('span');
        pip.className = 'pip' + (i < lv ? ' on' : '');
        pips.appendChild(pip);
      }
      card.appendChild(pips);

      var desc = document.createElement('div');
      desc.className = 'item-desc';
      desc.textContent = L({ en: d.en2 || d.per, vi: d.per });
      card.appendChild(desc);

      var btn = document.createElement('button');
      btn.className = 'btn';
      if (maxed) {
        btn.textContent = US.i18n.t('shop.equipped');
        btn.disabled = true;
      } else {
        btn.textContent = US.i18n.t('shop.buy') + ' — $' + US.util.fmt(cost);
        btn.onclick = function () {
          if (US.save.get().coins < cost) { toast(US.i18n.t('toast.notEnough')); return; }
          US.save.buyUpgrade(id, cost);
          US.audio.sfx('buy');
          toast('💪 ' + L(d) + ' Lv.' + ((sv.upgrades[id] | 0)));
          renderShop();
          refreshMenuStats();
        };
      }
      card.appendChild(btn);
      grid.appendChild(card);
    });
  }

  /* ---------------- daily quests + achievements ---------------- */
  function questBadge() {
    var sv = US.save.get();
    var claimable = (sv.quests.items || []).some(function (q) {
      return q.done && !q.claimed;
    });
    if ($('dot-quests')) $('dot-quests').classList.toggle('hidden', !claimable);
  }

  function renderQuests() {
    var sv = US.save.get();
    ensureUiQuests(sv);
    $('quest-streak').textContent = '🔥 ' + L({
      en: 'Login streak: day ' + (sv.quests.streak | 0),
      vi: 'Điểm danh ngày thứ ' + (sv.quests.streak | 0)
    }) + (sv.gems ? '   ·   🔥 ×' + sv.gems : '');
    $('h3-ach').textContent = '🏆 ' + L({ en: 'Achievements', vi: 'Thành tựu' });

    var list = $('quest-list');
    list.innerHTML = '';
    sv.quests.items.forEach(function (q) {
      var def = null;
      US.QUEST_POOL.forEach(function (d0) { if (d0.id === q.defId) def = d0; });
      if (!def) return;

      var row = document.createElement('div');
      row.className = 'item quest-row' + (q.claimed ? ' equipped' : '');
      var t = document.createElement('div');
      t.className = 'item-name';
      t.textContent = L(def.text);
      row.appendChild(t);

      var bar = document.createElement('div');
      bar.className = 'qbar';
      var fill = document.createElement('div');
      fill.className = 'qfill';
      fill.style.width = Math.min(100, (q.prog / q.goal) * 100) + '%';
      bar.appendChild(fill);
      row.appendChild(bar);

      var meta = document.createElement('div');
      meta.className = 'item-desc';
      meta.textContent = Math.min(q.prog, q.goal) + ' / ' + q.goal +
        '   ·   🔥 +' + def.gem + '   $+' + def.coins;
      row.appendChild(meta);

      var btn = document.createElement('button');
      btn.className = 'btn';
      if (q.claimed) { btn.textContent = '✓'; btn.disabled = true; }
      else if (q.done) {
        btn.textContent = L({ en: 'Claim', vi: 'Nhận thưởng' });
        btn.onclick = function () {
          q.claimed = true;
          US.save.addGems(def.gem);
          US.save.addCoins(def.coins);
          US.audio.sfx('buy');
          toast('📜 +🔥' + def.gem + '  +$' + def.coins);
          US.save.save();
          renderQuests();
          refreshMenuStats();
        };
      } else {
        btn.textContent = '…';
        btn.disabled = true;
      }
      row.appendChild(btn);
      list.appendChild(row);
    });

    // achievements
    var al = $('ach-list');
    al.innerHTML = '';
    Object.keys(US.ACHIEVEMENTS).forEach(function (id) {
      var d = US.ACHIEVEMENTS[id];
      var got = US.save.hasAch(id);
      var el = document.createElement('div');
      el.className = 'ach-row' + (got ? ' done' : '');
      el.textContent = (got ? '🏆 ' : '🔒 ') + L(d.text) + '  (🔥' + d.gem + ')';
      al.appendChild(el);
    });
  }

  function ensureUiQuests(sv) {
    // game.js owns the generator; nudge it via a run-less call
    if (!sv.quests.items || sv.quests.items.length !== 3 || sv.quests.date !== US.save.today()) {
      // replicate light version: full logic lives in game.js ensureQuests
      if (US.game && US.game.ensureQuests) US.game.ensureQuests();
      else {
        sv.quests.items = sv.quests.items || [];
      }
    }
  }

  /* ---------------- bestiary ---------------- */
  function renderBestiary() {
    var sv = US.save.get();
    var grid = $('bestiary-grid');
    grid.innerHTML = '';
    var keys = Object.keys(US.BESTIARY);
    var doneN = 0;
    keys.forEach(function (id) {
      var d = US.BESTIARY[id];
      var e = sv.bestiary[id] || { kills: 0, done: false };
      if (e.done) doneN++;

      var card = document.createElement('div');
      card.className = 'item best-card' + (e.done ? ' equipped' : (e.kills > 0 ? '' : ' locked'));

      var h = document.createElement('div');
      h.className = 'item-name';
      h.textContent = e.kills > 0 ? L(d.name) : '? ? ?';
      card.appendChild(h);

      card.appendChild(makePreview(104, 60, function (c2, w2, h2) {
        drawBeastIcon(c2, w2, h2, id, e.kills <= 0);
        if (e.done) {
          c2.strokeStyle = 'rgba(255,210,74,0.85)';
          c2.lineWidth = 2;
          c2.strokeRect(1.5, 1.5, w2 - 3, h2 - 3);
        }
      }));

      var lore = document.createElement('div');
      lore.className = 'item-desc';
      lore.textContent = e.done ? L(d.lore)
        : L({ en: 'Slay ' + d.goal + ' to reveal', vi: 'Hạ ' + d.goal + ' con để mở ký sự' }) +
          ' (' + Math.min(e.kills, d.goal) + '/' + d.goal + ')';
      card.appendChild(lore);

      var rw = document.createElement('div');
      rw.className = 'item-desc';
      rw.style.color = '#ffb938';
      rw.textContent = e.done ? '✓ 🔥' + d.gem : '🔥' + d.gem;
      card.appendChild(rw);

      grid.appendChild(card);
    });
    $('best-progress').textContent = '📖 ' + doneN + ' / ' + keys.length;
  }

  /* ---------------- rewarded ad stub (plug real SDK here) ---------------- */
  function setupAdButton(runCoins) {
    var btn = $('btn-adx2');
    if (!btn) return;
    if (!US.save.canWatchAd()) { btn.classList.add('hidden'); return; }
    btn.classList.remove('hidden');
    btn.textContent = L({
      en: '▶ Watch ad — bonus +50% amber (' + runCoins + ' → ' + Math.floor(runCoins * 1.5) + ')',
      vi: '▶ Xem quảng cáo — +50% hổ phách (' + runCoins + ' → ' + Math.floor(runCoins * 1.5) + ')'
    });
    btn.onclick = function () {
      btn.disabled = true;
      var left = 5;
      btn.textContent = L({ en: 'Ad playing… ', vi: 'Đang phát quảng cáo… ' }) + left + 's';
      var iv = setInterval(function () {
        left--;
        if (left > 0) { btn.textContent = L({ en: 'Ad playing… ', vi: 'Đang phát quảng cáo… ' }) + left + 's'; return; }
        clearInterval(iv);
        US.save.consumeAd();
        var bonus = Math.floor(runCoins * 0.5);
        US.save.addCoins(bonus);
        btn.classList.add('hidden');
        toast('💰 +' + bonus);
        US.audio.sfx('buy');
      }, 1000);
    };
  }

  /* ---------------- first-run tutorial ---------------- */
  var TUT_STEPS = [
    { en: 'Move with WASD / arrows (or the touch sticks).', vi: 'Di chuyển bằng WASD / mũi tên (hoặc joystick cảm ứng).' },
    { en: 'You auto-aim and auto-fire at the nearest beast.', vi: 'Bạn tự ngắm và tự bắn vào con thú gần nhất.' },
    { en: 'Kill fast to build COMBO and go ON FIRE — double damage!', vi: 'Giết nhanh để lên COMBO và BÙNG CHÁY — sát thương x2!' },
    { en: 'Grab the amber ($) they drop — spend it on weapons & permanent power.', vi: 'Nhặt hổ phách ($) rơi ra — dùng mua vũ khí & nâng cấp vĩnh viễn.' },
    { en: 'Every 5th wave a BOSS stalks in. Feel the footsteps. Good luck, chief.', vi: 'Mỗi wave thứ 5 trùm sẽ xuất hiện. Nghe tiếng bước chân đi. Chúc may mắn, thủ lĩnh.' }
  ];
  var tutStep = -1;

  function startTutorial() {
    tutStep = 0;
    showTutStep();
    show($('overlay-tutorial'));
  }
  function showTutStep() {
    $('tut-title').textContent = L({ en: 'Welcome to the Valley', vi: 'Chào mừng đến Thung Lũng' });
    $('tut-step').textContent = L(TUT_STEPS[tutStep]);
    $('btn-tut-next').textContent = tutStep >= TUT_STEPS.length - 1
      ? L({ en: 'Let’s hunt!', vi: 'Đi săn thôi!' })
      : L({ en: 'Next', vi: 'Tiếp' });
  }
  function endTutorial() {
    hide($('overlay-tutorial'));
    US.save.get().tut = true;
    US.save.save();
    tutStep = -1;
  }

  /* ---------------- wiring ---------------- */
  function init() {
    US.i18n.setLang(US.save.get().lang);
    US.i18n.apply();

    $('btn-campaign').onclick = function () { US.audio.resume(); US.audio.sfx('ui'); US.game.start('campaign'); showScreen(null); };
    $('btn-arena').onclick = function () { US.audio.sfx('ui'); showScreen('arena-setup'); };
    $('btn-shop').onclick = function () { US.audio.sfx('ui'); renderShop(); showScreen('shop'); };
    $('btn-settings').onclick = function () { US.audio.sfx('ui'); bindSettings(); showScreen('settings'); };
    $('btn-rank').onclick = function () { US.audio.sfx('ui'); renderRank(); showScreen('rank'); };
    $('btn-howto').onclick = function () { US.audio.sfx('ui'); showScreen('howto'); };
    // commercialization screens — guarded so a stale HTML shell can never
    // crash menu init (feature buttons simply stay hidden)
    // subtle hover tick on the pro menu list
    document.querySelectorAll('.btn-menu').forEach(function (b) {
      b.addEventListener('mouseenter', function () {
        if (US.audio && US.audio.hoverTick) US.audio.hoverTick();
      });
    });

    if ($('btn-quests')) $('btn-quests').onclick = function () { US.audio.sfx('ui'); renderQuests(); showScreen('quests'); };
    if ($('btn-bestiary')) $('btn-bestiary').onclick = function () { US.audio.sfx('ui'); renderBestiary(); showScreen('bestiary'); };
    if ($('btn-upgrades')) $('btn-upgrades').onclick = function () { US.audio.sfx('ui'); shopTab = 'upgrades'; renderShop(); showScreen('shop'); };

    function setTxt(id, v) { if ($(id)) $(id).textContent = v; }
    setTxt('lbl-quests', L({ en: 'Quests', vi: 'Nhiệm vụ' }));
    setTxt('lbl-bestiary', L({ en: 'Bestiary', vi: 'Ký sự thú' }));
    setTxt('lbl-upgrades', L({ en: 'Upgrades', vi: 'Nâng cấp' }));
    setTxt('lbl-tabup', L({ en: 'Upgrades', vi: 'Nâng cấp' }));
    setTxt('h2-quests', '📜 ' + L({ en: 'Daily Quests', vi: 'Nhiệm vụ mỗi ngày' }));
    setTxt('h2-best', '📖 ' + L({ en: 'Bestiary of the Valley', vi: 'Ký sự thú thung lũng' }));
    setTxt('lbl-shakeamt', L({ en: 'Screen shake', vi: 'Rung màn hình' }));
    setTxt('lbl-quality', L({ en: 'Effects quality', vi: 'Chất lượng hiệu ứng' }));

    document.querySelectorAll('[data-back]').forEach(function (b) {
      b.onclick = function () { US.audio.sfx('ui'); showScreen('menu'); };
    });

    [['tab-weapons', 'weapons'], ['tab-heroes', 'heroes'], ['tab-skins', 'skins'], ['tab-upgrades', 'upgrades']].forEach(function (p) {
      $(p[0]).onclick = function () { US.audio.sfx('ui'); shopTab = p[1]; renderShop(); };
    });

    // arena setup
    $('arena-bots').onchange = function () {};
    $('arena-target').onchange = function () {};
    $('arena-start').onclick = function () {
      US.audio.resume();
      US.audio.sfx('ui');
      US.game.start('arena', {
        arena: {
          bots: parseInt($('arena-bots').value, 10),
          target: parseInt($('arena-target').value, 10)
        }
      });
      showScreen(null);
    };

    // first-run tutorial (guarded for stale shells)
    if ($('overlay-tutorial') && !$('overlay-tutorial').classList.contains('hidden')) hide($('overlay-tutorial'));
    if (!$('btn-tut-next')) return;
    $('btn-tut-next').onclick = function () {
      US.audio.sfx('ui');
      if (tutStep >= TUT_STEPS.length - 1) endTutorial();
      else { tutStep++; showTutStep(); }
    };
    $('btn-tut-skip').onclick = function () { US.audio.sfx('ui'); endTutorial(); };
    $('btn-tut-skip').textContent = L({ en: 'Skip', vi: 'Bỏ qua' });
    if (!US.save.get().tut && !$('btn-retry').onclick) setTimeout(startTutorial, 400);

    // pause
    $('btn-pause').onclick = function () {
      if (US.game.pause()) { US.audio.sfx('ui'); showPause(); }
    };
    $('btn-resume').onclick = function () {
      if (US.game.resume()) { US.audio.sfx('ui'); hidePause(); }
    };
    $('btn-quit').onclick = function () {
      // bank the run politely before leaving
      var g = US.game.get();
      if (g && !g.over && g.mode === 'campaign' && (g.wave > 0)) {
        US.save.addCoins(g.runCoins);
        US.save.submitRun(g.score, g.wave || 0);
      }
      US.game.stop();
      US.ui.hideRevive();
      hidePause();
      hide($('overlay-over'));
      hide($('overlay-cards'));
      showScreen('menu');
    };

    // game over
    $('btn-retry').onclick = function () {
      var g = US.game.get();
      var mode = g ? g.mode : 'campaign';
      US.game.stop();
      hide($('overlay-over'));
      US.audio.sfx('ui');
      if (mode === 'arena') showScreen('arena-setup');
      else { US.game.start('campaign'); showScreen(null); }
    };
    $('btn-tomenu').onclick = function () {
      US.game.stop();
      hide($('overlay-over'));
      showScreen('menu');
    };

    // revive
    $('btn-revive').onclick = function () { US.audio.sfx('buy'); US.game.acceptRevive(); };
    $('btn-nodecline').onclick = function () { US.game.declineRevive(); };

    showScreen('menu');
  }

  US.ui = {
    init: init,
    showCardPick: showCardPick,
    gameOver: gameOver,
    arenaOver: arenaOver,
    showRevive: showRevive,
    hideRevive: hideRevive,
    toast: toast,
    questBadge: questBadge
  };
})();