app.js

window.onerror = (msg, url, line) => {
  const banner = document.getElementById('debug-banner');
  if (banner) {
    banner.textContent = `JS Error: ${msg} (line ${line})`;
    banner.classList.remove('hidden');
  }
};

// ============================================================
// CONFIG & STATE
// ============================================================
const STREAM_API_URL = "https://aqhedgyiworhbfkrzreb.supabase.co/functions/v1/quick-processor";
const TTS_API_URL = "https://aqhedgyiworhbfkrzreb.supabase.co/functions/v1/swift-worker";
const TRANSLITERATE_API_URL = "https://aqhedgyiworhbfkrzreb.supabase.co/functions/v1/quick-task";
const RAZORPAY_KEY_ID = "rzp_test_TZ9SeSSO5G8eCq";

const firebaseConfig = {
  apiKey: "AIzaSyAChu97QI-tyulpisxH6aECBYlj88DGB1o",
  authDomain: "arki-ai-280b8.firebaseapp.com",
  projectId: "arki-ai-280b8",
  storageBucket: "arki-ai-280b8.firebasestorage.app",
  messagingSenderId: "1075792140029",
  appId: "1:1075792140029:web:9f3af7c6b89530c7ee9094",
  measurementId: "G-PL1YY34MBZ"
};

const UI_TRANSLATIONS = {
  en: {
    welcomeTitle: "Welcome",
    welcomeSub: "Start chatting with Orki AI",
    inputPlaceholder: "Message Orki...",
    newChat: "New Chat",
    conversations: "Conversations",
    dailyQuota: "Daily Quota",
    disclaimer: "Orki AI can make mistakes. Always double check."
  },
  deva: {
    welcomeTitle: "बरायबाय",
    welcomeSub: "Orki AI जों सावरायनायखौ जागायदो",
    inputPlaceholder: "Orki नो लिरहर...",
    newChat: "गोदानै सावराय",
    conversations: "सावरायनायफोर",
    dailyQuota: "सानसेनि बाहायनाय",
    disclaimer: "Orki AI आबो गोरोन्थि खालामनो हागौ। खेबसे नायबिजिर फिन।"
  },
  roman: {
    welcomeTitle: "Boraibai",
    welcomeSub: "Orki AI jwng saorainaikow jagaidw",
    inputPlaceholder: "Orki nw lirhor...",
    newChat: "Gwdanwi Saorai",
    conversations: "Saorainaifwr",
    dailyQuota: "Sanseni Bahainai",
    disclaimer: "Orki AI bw gwrwnti khalamnw hagwu. kebse nai bijir fin."
  }
};

const DAILY_LIMITS = { Guest: 5, Free: 20, Plus: 60, Pro: Infinity };
const MEMORY_DEPTH = { Guest: -4, Free: -6, Plus: -12, Pro: -60 };
const PRICING = {
  weekly: { plus: 29, pro: 59, plusPaise: 2900, proPaise: 5900, label: '/wk' },
  monthly: { plus: 99, pro: 199, plusPaise: 9900, proPaise: 19900, label: '/mo' },
  yearly: { plus: 799, pro: 1599, plusPaise: 79900, proPaise: 159900, label: '/yr' }
};

const $ = id => document.getElementById(id);
const on = (id, event, handler) => {
  const el = $(id);
  if (el) el.addEventListener(event, handler);
};

const safeGet = (key, fallback) => {
  try { return localStorage.getItem(key) || fallback; } catch { return fallback; }
};
const safeSet = (key, val) => {
  try { localStorage.setItem(key, val); } catch {}
};
const getTodayString = () => new Date().toISOString().split('T')[0];

let currentScript = safeGet('arki_script', 'deva');
let uiLanguage = safeGet('arki_ui_lang', 'deva');
let userPersona = safeGet('arki_persona', '');
let userName = safeGet('arki_username', '');

let currentUser = null, currentPlan = "Free", selectedModel = 'orki-3.0', currentDailyUsage = 0;
let abortController = null, isGenerating = false, currentChatId = null;
let currentChatMessages = [], selectedCycle = 'monthly', cachedThreads = [], isIncognito = false;
let mediaRecorder = null, audioChunks = [], isRecording = false;
let isLiveTalkActive = false, liveTalkAudioCtx = null, liveTalkAnalyser = null, liveTalkSilenceTimer = null, liveTalkStream = null;
let currentAudio = null, activeTtsBtn = null, ttsAudioCache = new Map();

// Unlock mobile autoplay by priming a silent clip on a real user tap.
// Reuses the same currentAudio instance that playBodoSpeech/bindAudioToPlayer
// already control, so there's only ever one audio player in the app.
function unlockAudio() {
  if (!currentAudio) currentAudio = new Audio();
  currentAudio.src = 'data:audio/wav;base64,UklGRigAAABXQVZFZm10IBIAAAABAAEARKwAAIhYAQACABAAAABkYXRhAgAAAAEA';
  currentAudio.play().catch(() => {});
}

// Synthesized "live talk opening" chime — a soft rising two-note
// swell, generated in-browser so it plays instantly with zero
// network requests or bundled audio files.
function playLiveTalkOpenSound() {
  try {
    const AudioCtx = window.AudioContext || window.webkitAudioContext;
    const ctx = new AudioCtx();
    const now = ctx.currentTime;

    const notes = [
      { freq: 523.25, start: 0, dur: 0.16 },   // C5
      { freq: 783.99, start: 0.10, dur: 0.22 } // G5
    ];

    notes.forEach(({ freq, start, dur }) => {
      const osc = ctx.createOscillator();
      const gain = ctx.createGain();
      osc.type = 'sine';
      osc.frequency.setValueAtTime(freq, now + start);
      gain.gain.setValueAtTime(0, now + start);
      gain.gain.linearRampToValueAtTime(0.18, now + start + 0.02);
      gain.gain.exponentialRampToValueAtTime(0.0001, now + start + dur);
      osc.connect(gain);
      gain.connect(ctx.destination);
      osc.start(now + start);
      osc.stop(now + start + dur + 0.02);
    });

    setTimeout(() => ctx.close().catch(() => {}), 600);
  } catch (e) {
    console.warn("Live talk chime unavailable:", e);
  }
}
let auth = null, db = null;

// ============================================================
// TRANSLITERATION ENGINE
// ============================================================
async function cleanBodoText(devanagariText) {
  try {
    const res = await fetch(TRANSLITERATE_API_URL, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ text: devanagariText })
    });
    const data = await res.json();
    return data.roman || devanagariText;
  } catch (err) {
    console.error("Transliteration failed:", err);
    return devanagariText;
  }
}

// ============================================================
// DOM ELEMENTS
// ============================================================
const chat = $('chat'), form = $('chat-form'), input = $('prompt'), sendBtn = $('send-btn'), thinking = $('thinking'), micBtn = $('mic-btn');
const liveTalkBtn = $('live-talk-btn'), liveTalkPulse = $('live-talk-pulse'), liveTalkIcon = $('live-talk-icon');
const liveTalkOverlay = $('live-talk-overlay'), liveTalkOrb = $('live-talk-orb'), liveTalkRing = $('live-talk-ring');
const liveTalkStatusPill = $('live-talk-status-pill'), liveTalkTranscript = $('live-talk-transcript'), liveTalkEndBtn = $('live-talk-end-btn');
const menuBtn = $('menu-btn'), drawer = $('drawer'), drawerBackdrop = $('drawer-backdrop'), closeDrawer = $('close-drawer');
const newChatBtn = $('new-chat-btn'), incognitoBtn = $('incognito-btn'), incognitoBadge = $('incognito-badge'), clearAllBtn = $('clear-all-btn'), historyList = $('history-list');
const authActionBtn = $('auth-action-btn');
const authModal = $('auth-modal'), authError = $('auth-error');
const userDisplay = $('user-display'), userPlan = $('user-plan'), upgradeBtn = $('upgrade-btn'), syncStatus = $('sync-status');
const modelSelectBtn = $('model-select-btn'), modelDropdown = $('model-dropdown'), currentModelDisplay = $('current-model-display'), selectOrki = $('select-orki'), selectOkafwr = $('select-okafwr'), okafwrLockIcon = $('okafwr-lock-icon');
const usageCountText = $('usage-count-text'), usageProgressBar = $('usage-progress-bar');
const upgradeModal = $('upgrade-modal'), closeUpgrade = $('close-upgrade'), cycleWeekly = $('cycle-weekly'), cycleMonthly = $('cycle-monthly'), cycleYearly = $('cycle-yearly');
const plusPriceText = $('plus-price'), proPriceText = $('pro-price'), buyPlusBtn = $('buy-plus-btn'), buyProBtn = $('buy-pro-btn');
const openSettingsBtn = $('open-settings'), closeSettingsBtn = $('close-settings'), settingsModal = $('settings-modal');
const optDeva = $('opt-deva'), optRom = $('opt-rom'), optUiDeva = $('opt-ui-deva'), optUiRom = $('opt-ui-rom'), optUiEn = $('opt-ui-en');
const usernameInput = $('username-input'), personaInput = $('persona-input'), saveSettingsBtn = $('save-settings');

const ACTIVE_BTN = "py-2 rounded-lg text-xs font-semibold bg-emerald-600 text-white transition cursor-pointer";
const INACTIVE_BTN = "py-2 rounded-lg text-xs font-medium text-zinc-400 hover:text-white transition cursor-pointer";
const stopIcon = `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="currentColor" class="w-4 h-4 pointer-events-none"><rect x="6" y="6" width="12" height="12" rx="2"/></svg>`;
const sendIcon = `<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="currentColor" class="w-4 h-4 transform rotate-[-45deg] translate-x-0.5 -translate-y-0.5 pointer-events-none"><path d="M3.478 2.404a.75.75 0 0 0-.926.941l2.432 7.905H13.5a.75.75 0 0 1 0 1.5H4.984l-2.432 7.905a.75.75 0 0 0 .926.94 60.519 60.519 0 0 0 18.445-8.986.75.75 0 0 0 0-1.218A60.517 60.517 0 0 0 3.478 2.404Z"/></svg>`;
const trashIcon = `<svg xmlns="http://www.w3.org/2000/svg" class="w-3.5 h-3.5 pointer-events-none" fill="none" viewBox="0 0 24 24" stroke="currentColor" stroke-width="2"><path stroke-linecap="round" stroke-linejoin="round" d="M19 7l-.867 12.142A2 2 0 0116.138 21H7.862a2 2 0 01-1.995-1.858L5 7m5 4v6m4-6v6m1-10V4a1 1 0 00-1-1h-4a1 1 0 00-1 1v3M4 7h16"/></svg>`;

// ============================================================
// UI HELPERS
// ============================================================
function openAuthModal() {
  if (authError) authError.classList.add('hidden');
  if (authModal) authModal.classList.remove('hidden');
}

function applyUILanguage(lang) {
  const t = UI_TRANSLATIONS[lang] || UI_TRANSLATIONS.en;
  const set = (id, val) => { const el = $(id); if (el) el.textContent = val; };
  const qSet = (sel, val) => { const el = document.querySelector(sel); if (el) el.textContent = val; };
  qSet('#welcome-screen h2', t.welcomeTitle);
  qSet('#welcome-screen p', t.welcomeSub);
  if (input && currentUser) input.placeholder = t.inputPlaceholder;
  set('new-chat-label', t.newChat);
  set('quota-label', t.dailyQuota);
  set('conversations-label', t.conversations);
  set('disclaimer-label', t.disclaimer);
}

function setGeneratingState(generating) {
  isGenerating = generating;
  if (!sendBtn) return;
  if (generating) {
    sendBtn.classList.replace('bg-emerald-600', 'bg-red-600');
    sendBtn.classList.replace('hover:bg-emerald-500', 'hover:bg-red-500');
    sendBtn.title = "Stop generating";
    sendBtn.innerHTML = stopIcon;
  } else {
    sendBtn.classList.replace('bg-red-600', 'bg-emerald-600');
    sendBtn.classList.replace('hover:bg-red-500', 'hover:bg-emerald-500');
    sendBtn.title = "Send message";
    sendBtn.innerHTML = sendIcon;
  }
}

function updateUsageUI() {
  if (!usageCountText || !usageProgressBar) return;
  const limit = DAILY_LIMITS[currentPlan] || 20;
  if (limit === Infinity) {
    usageCountText.textContent = "Unlimited";
    usageCountText.className = "text-[10px] font-bold text-amber-400";
    usageProgressBar.style.width = "100%";
    usageProgressBar.className = "h-full bg-amber-400 rounded-full";
    return;
  }
  const pct = Math.min(100, Math.round((currentDailyUsage / limit) * 100));
  usageCountText.textContent = `${currentDailyUsage} / ${limit}`;
  usageCountText.className = pct >= 100 ? "text-[10px] font-bold text-red-400" : "text-[10px] font-medium text-zinc-400";
  usageProgressBar.style.width = `${pct}%`;
  usageProgressBar.className = `h-full rounded-full transition-all duration-300 ${pct >= 90 ? 'bg-red-500' : pct >= 70 ? 'bg-amber-500' : 'bg-emerald-500'}`;
}

function updateModelLockUI() {
  if (!okafwrLockIcon) return;
  okafwrLockIcon.textContent = currentPlan === 'Pro' ? '✓' : '🔒';
  okafwrLockIcon.className = currentPlan === 'Pro' ? 'text-amber-400 text-xs font-bold' : 'text-zinc-500 text-xs';
}

function updateIncognitoUI() {
  if (incognitoBadge) incognitoBadge.classList.toggle('hidden', !isIncognito);
  if (incognitoBtn) {
    incognitoBtn.className = isIncognito
      ? "px-3 py-2 rounded-xl bg-purple-950/60 border border-purple-500 text-purple-300 text-xs font-medium transition cursor-pointer flex items-center gap-1 shrink-0 shadow-sm"
      : "px-3 py-2 rounded-xl bg-zinc-800 hover:bg-zinc-700 text-zinc-400 hover:text-purple-300 text-xs font-medium transition cursor-pointer border border-zinc-700/50 flex items-center gap-1 shrink-0";
  }
}

function updatePricingUI() {
  const p = PRICING[selectedCycle];
  if (plusPriceText) plusPriceText.innerHTML = `₹${p.plus}<span class="text-xs text-zinc-500 font-normal">${p.label}</span>`;
  if (proPriceText) proPriceText.innerHTML = `₹${p.pro}<span class="text-xs text-zinc-500 font-normal">${p.label}</span>`;
  [cycleWeekly, cycleMonthly, cycleYearly].forEach(btn => {
    if (btn) {
      const isActive = selectedCycle === btn.id.replace('cycle-', '');
      btn.className = `py-1.5 rounded-lg transition cursor-pointer ${isActive ? 'bg-emerald-600 text-white font-semibold' : 'font-medium text-zinc-400 hover:text-white'}`;
    }
  });
}

function updateScriptUI() {
  if (!optDeva || !optRom) return;
  optDeva.className = currentScript === 'deva' ? ACTIVE_BTN : INACTIVE_BTN;
  optRom.className = currentScript === 'roman' ? ACTIVE_BTN : INACTIVE_BTN;
}

function updateUiLangUI() {
  if (!optUiDeva || !optUiRom || !optUiEn) return;
  optUiDeva.className = uiLanguage === 'deva' ? ACTIVE_BTN : INACTIVE_BTN;
  optUiRom.className = uiLanguage === 'roman' ? ACTIVE_BTN : INACTIVE_BTN;
  optUiEn.className = uiLanguage === 'en' ? ACTIVE_BTN : INACTIVE_BTN;
}

// ============================================================
// CORE LOGIC & TTS ENGINE
// ============================================================
function buildPersonaContext() {
  return [userName ? `The user's name is ${userName}; address them by name naturally.` : '', userPersona].filter(Boolean).join(' ');
}

function renderMarkdown(text) {
  try {
    if (window.marked && typeof window.marked.parse === 'function') return window.marked.parse(text);
  } catch {}
  return text.replace(/\n/g, '<br>');
}

function createWelcomeScreen() {
  const div = document.createElement('div');
  div.id = 'welcome-screen';
  div.className = 'flex-1 flex flex-col items-center justify-center select-none text-center';
  div.innerHTML = `<h2 class="text-emerald-400 font-semibold text-xl tracking-wide">Welcome</h2><p class="text-xs text-zinc-500 mt-1">Start chatting with Orki AI</p>`;
  return div;
}

function startNewChat() {
  if (isGenerating && abortController) abortController.abort();
  currentChatId = null;
  currentChatMessages = [];
  if (chat) {
    chat.innerHTML = '';
    chat.appendChild(createWelcomeScreen());
  }
  toggleDrawer(false);
  renderHistorySidebar();
}

function toggleDrawer(open) {
  if (!drawer || !drawerBackdrop) return;
  drawer.style.transform = open ? 'translateX(0%)' : 'translateX(-100%)';
  drawerBackdrop.classList.toggle('hidden', !open);
}

function ensureDevanagariForTTS(text) {
  if (/[\u0900-\u097F]/.test(text)) return text;
  return text
    .toLowerCase()
    .replace(/\bkhulumbai\b/g, "खुलुमबाय")
    .replace(/\bmabwi\b/g, "माबोरै")
    .replace(/\bmabrwi\b/g, "माबोरै")
    .replace(/\bmabwrwi\b/g, "माबोरै")
    .replace(/\bmwjang\b/g, "मोजां")
    .replace(/\bmwzang\b/g, "मोजां")
    .replace(/\bjwmwi\b/g, "जोम्वै")
    .replace(/\bdong\b/g, "दं")
    .replace(/\bdonga\b/g, "दङ")
    .replace(/\bnwng\b/g, "नों")
    .replace(/\bnwngha\b/g, "नोंहा")
    .replace(/\bang\b/g, "आं")
    .replace(/\bangha\b/g, "आंहा")
    .replace(/\bma\b/g, "मा")
    .replace(/\bkhobor\b/g, "खबर")
    .replace(/\bthang\b/g, "थां")
    .replace(/\bthangnw\b/g, "थांनो")
    .replace(/\bkhalam\b/g, "खालाम")
    .replace(/\bkhalamnw\b/g, "खालामनो")
    .replace(/\bswr\b/g, "सोर")
    .replace(/\bboha\b/g, "बहा")
    .replace(/\bfai\b/g, "फै")
    .replace(/\bphai\b/g, "फै")
    .replace(/\bonkham\b/g, "ओंखाम")
    .replace(/\bwngkham\b/g, "ओंखाम")
    .replace(/kh/g, "ख").replace(/ph/g, "फ").replace(/th/g, "थ")
    .replace(/ng/g, "ं")
    .replace(/wi/g, "ुइ").replace(/ai/g, "ै").replace(/ao/g, "ौ")
    .replace(/jw/g, "जो").replace(/nw/g, "नो").replace(/bw/g, "बो").replace(/w/g, "ु")
    .replace(/b/g, "ब").replace(/d/g, "द").replace(/g/g, "ग").replace(/h/g, "ह")
    .replace(/j/g, "ज").replace(/k/g, "क").replace(/l/g, "ल").replace(/m/g, "म")
    .replace(/n/g, "न").replace(/p/g, "प").replace(/r/g, "र").replace(/s/g, "स")
    .replace(/t/g, "त").replace(/y/g, "य").replace(/z/g, "ज")
    .replace(/a/g, "ा").replace(/i/g, "ि").replace(/u/g, "ु").replace(/e/g, "े").replace(/o/g, "ो");
}

function cleanTextForTTS(rawText) {
  const cleaned = rawText
    .replace(/[#*_`~>\[\]\(\)]/g, '')
    .replace(/[\u{1F600}-\u{1F64F}\u{1F300}-\u{1F5FF}\u{1F680}-\u{1F6FF}\u{2600}-\u{26FF}]/gu, '')
    .trim();
  return ensureDevanagariForTTS(cleaned);
}

// ============================================================
// FLOATING AUDIO PILL CONTROLLER
// ============================================================
const audioPlayerBar = $('audio-player-bar');
const playerToggleBtn = $('player-toggle-btn');
const playerPlayIcon = $('player-play-icon');
const playerPauseIcon = $('player-pause-icon');
const playerTimer = $('player-timer');
const playerSeeker = $('player-seeker');
const playerCloseBtn = $('player-close-btn');
const playerLoadingIcon = $('player-loading-icon');

function formatAudioTime(seconds) {
  if (isNaN(seconds)) return "00:00";
  const m = Math.floor(seconds / 60).toString().padStart(2, '0');
  const s = Math.floor(seconds % 60).toString().padStart(2, '0');
  return `${m}:${s}`;
}

function showPlayerLoading() {
  if (!audioPlayerBar) return;
  audioPlayerBar.classList.remove('hidden');
  playerPlayIcon?.classList.add('hidden');
  playerPauseIcon?.classList.add('hidden');
  playerLoadingIcon?.classList.remove('hidden');
  if (playerTimer) playerTimer.textContent = "--:--";
  if (playerSeeker) {
    playerSeeker.value = 0;
    playerSeeker.disabled = true;
  }
  if (playerToggleBtn) playerToggleBtn.disabled = true;
}

function bindAudioToPlayer(audio) {
  if (!audioPlayerBar) return;
  audioPlayerBar.classList.remove('hidden');
  playerLoadingIcon?.classList.add('hidden');
  if (playerSeeker) playerSeeker.disabled = false;
  if (playerToggleBtn) playerToggleBtn.disabled = false;

  audio.ontimeupdate = () => {
    playerTimer.textContent = formatAudioTime(audio.currentTime);
    if (audio.duration) {
      playerSeeker.value = (audio.currentTime / audio.duration) * 100;
    }
  };
  audio.onplay = () => {
    playerPlayIcon?.classList.add('hidden');
    playerPauseIcon?.classList.remove('hidden');
  };
  audio.onpause = () => {
    playerPlayIcon?.classList.remove('hidden');
    playerPauseIcon?.classList.add('hidden');
  };
  audio.onended = () => {
    audioPlayerBar.classList.add('hidden');
    if (playerSeeker) playerSeeker.value = 0;
    if (playerTimer) playerTimer.textContent = "00:00";
    if (activeTtsBtn) activeTtsBtn.innerHTML = `🔊 Listen`;
    currentAudio = null;
    activeTtsBtn = null;
  };
}

on('player-toggle-btn', 'click', () => {
  if (!currentAudio) return;
  if (currentAudio.paused) currentAudio.play();
  else currentAudio.pause();
});

if (playerSeeker) {
  playerSeeker.oninput = () => {
    if (currentAudio && currentAudio.duration) {
      currentAudio.currentTime = (playerSeeker.value / 100) * currentAudio.duration;
    }
  };
}

on('player-close-btn', 'click', () => {
  if (currentAudio) {
    currentAudio.pause();
    currentAudio.currentTime = 0;
    currentAudio = null;
  }
  if (activeTtsBtn) activeTtsBtn.innerHTML = `🔊 Listen`;
  activeTtsBtn = null;
  audioPlayerBar?.classList.add('hidden');
});

async function playBodoSpeech(btn, text) {
  if (activeTtsBtn === btn && currentAudio && !currentAudio.paused) {
    currentAudio.pause();
    btn.innerHTML = `🔊 Listen`;
    return;
  }
  if (currentAudio) {
    currentAudio.pause();
    if (activeTtsBtn) activeTtsBtn.innerHTML = `🔊 Listen`;
  }
  const cleanText = cleanTextForTTS(text);
  if (!cleanText) return;

  showPlayerLoading();

  if (ttsAudioCache.has(cleanText)) {
    activeTtsBtn = btn;
    btn.disabled = false;
    btn.innerHTML = `⏹ Stop`;
    if (!currentAudio) currentAudio = new Audio();
    currentAudio.src = ttsAudioCache.get(cleanText);
    bindAudioToPlayer(currentAudio);
    const cachedBaseOnEnded = currentAudio.onended;
    currentAudio.onended = () => {
      cachedBaseOnEnded && cachedBaseOnEnded();
      btn.innerHTML = `🔊 Listen`;
    };
    try {
      await currentAudio.play();
    } catch {
      btn.innerHTML = `⚠️ Retry`;
    }
    return;
  }

  try {
    activeTtsBtn = btn;
    btn.disabled = true;
    btn.innerHTML = `<span class="animate-pulse">⏳ Rendering...</span>`;
    const res = await fetch(TTS_API_URL, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ text: cleanText })
    });
    if (!res.ok) {
      const errData = await res.json().catch(() => ({}));
      throw new Error(errData.error || `Server status ${res.status}`);
    }
    const data = await res.json();
    const audioUrl = data.audioUrl;
    if (!audioUrl) throw new Error("Audio URL missing from server response");

    ttsAudioCache.set(cleanText, audioUrl);
    btn.disabled = false;
    btn.innerHTML = `⏹ Stop`;
    if (!currentAudio) currentAudio = new Audio();
    currentAudio.src = audioUrl;
    bindAudioToPlayer(currentAudio);
    const freshBaseOnEnded = currentAudio.onended;
    currentAudio.onended = () => {
      freshBaseOnEnded && freshBaseOnEnded();
      btn.innerHTML = `🔊 Listen`;
    };
    await currentAudio.play();
  } catch (err) {
    console.error("TTS generation error:", err);
    btn.disabled = false;
    btn.innerHTML = `⚠️ Retry`;
    audioPlayerBar?.classList.add('hidden');
    alert(`TTS Failed: ${err.message}`);
  }
}

function attachTtsButton(bubble, text) {
  if (!bubble || !text.trim()) return;
  const actionRow = document.createElement('div');
  actionRow.className = "flex items-center gap-2 mt-2 pt-1 border-t border-zinc-700/30";
  const ttsBtn = document.createElement('button');
  ttsBtn.type = "button";
  ttsBtn.className = "text-[11px] font-medium text-zinc-400 hover:text-emerald-400 flex items-center gap-1 transition cursor-pointer";
  ttsBtn.innerHTML = `🔊 Listen`;
  ttsBtn.onclick = () => playBodoSpeech(ttsBtn, text.trim());
  actionRow.appendChild(ttsBtn);
  bubble.appendChild(actionRow);
}

function createBubbleElement(role) {
  const wrapper = document.createElement('div');
  wrapper.className = `flex ${role === 'user' ? 'justify-end' : 'justify-start'}`;
  const bubble = document.createElement('div');
  bubble.className = role === 'user'
    ? 'bg-emerald-600 text-white rounded-2xl rounded-tr-xs px-4 py-2.5 max-w-[85%] text-[15px] whitespace-pre-wrap leading-relaxed shadow-sm break-words [overflow-wrap:anywhere]'
    : 'bg-[#242427] border border-zinc-700/40 text-zinc-100 rounded-2xl rounded-tl-xs px-4 py-2.5 max-w-[85%] text-[15px] shadow-sm leading-relaxed prose-custom break-words [overflow-wrap:anywhere]';
  wrapper.appendChild(bubble);
  if (chat) {
    chat.appendChild(wrapper);
    chat.scrollTop = chat.scrollHeight;
  }
  return bubble;
}

function appendMessage(role, text) {
  const bubble = createBubbleElement(role);
  bubble.innerHTML = role === 'user' ? text : renderMarkdown(text);
  if (role === 'model') attachTtsButton(bubble, text);
  if (chat) chat.scrollTop = chat.scrollHeight;
}

async function processStream(reader, onChunk) {
  const decoder = new TextDecoder('utf-8');
  let buffer = '';
  while (true) {
    const { done, value } = await reader.read();
    if (done) break;
    buffer += decoder.decode(value, { stream: true });
    const lines = buffer.split('\n');
    buffer = lines.pop();
    for (const line of lines) {
      const trimmed = line.trim();
      if (trimmed.startsWith('data: ')) {
        const jsonStr = trimmed.slice(6).trim();
        if (!jsonStr) continue;
        try {
          const parsed = JSON.parse(jsonStr);
          const chunk = parsed.candidates?.[0]?.content?.parts?.[0]?.text || '';
          if (chunk) onChunk(chunk);
        } catch {}
      }
    }
  }
}

async function getAuthToken() {
  if (!auth || !auth.currentUser) return null;
  try {
    return await auth.currentUser.getIdToken();
  } catch (e) {
    console.warn("Failed to get ID token:", e);
    return null;
  }
}

async function persistUsageIncrement() {
  currentDailyUsage++;
  updateUsageUI();
  const today = getTodayString();
  if (currentUser && db) {
    try {
      await db.collection("users").doc(currentUser.uid).set({
        dailyUsage: { date: today, count: currentDailyUsage }
      }, { merge: true });
    } catch (e) {
      console.warn("Usage sync error:", e);
    }
  } else {
    safeSet('arki_guest_usage', JSON.stringify({ date: today, count: currentDailyUsage }));
  }
}

// ============================================================
// DUAL RESPONSE PARSER (display text vs. clean TTS text)
// ============================================================
function parseDualResponse(rawText) {
  if (!rawText.includes('---TTS---')) {
    return { displayText: rawText.trim(), ttsText: rawText.trim() };
  }
  const [displayPart, ...ttsParts] = rawText.split('---TTS---');
  return { displayText: displayPart.trim(), ttsText: ttsParts.join('---TTS---').trim() };
}

// ============================================================
// SEND HANDLERS
// ============================================================
async function handleSend() {
  if (isGenerating) {
    abortController?.abort();
    return;
  }

  const limit = DAILY_LIMITS[currentPlan] || 20;
  if (currentDailyUsage >= limit) {
    if (!currentUser) {
      alert(`You've used your ${limit} free guest messages for today. Sign in with Google for a higher daily limit.`);
      openAuthModal();
    } else {
      alert(`You reached your daily limit of ${limit} messages. Upgrade to get higher limits.`);
      upgradeModal && upgradeModal.classList.remove('hidden');
    }
    return;
  }

  const userText = input ? input.value.trim() : '';
  if (!userText) return;

  const welcome = $('welcome-screen');
  if (welcome) welcome.remove();

  appendMessage('user', userText);
  currentChatMessages.push({ role: 'user', text: userText });
  input.value = '';
  input.style.height = 'auto';
  setGeneratingState(true);
  thinking && thinking.classList.remove('hidden');

  const scriptConstraint = currentScript === 'roman'
    ? `\n[Constraint:1. Provide the reply in natural, colloquial Roman Bodo (using 'w', 'dong', and keeping English words like 'Spanish', 'phone' as-is).2. Follow immediately with '---TTS---' on a new line, then the EXACT same sentence in Bodo Devanagari script (बर' हांखो) for speech synthesis.Example format:Oi jwmwi! Spanish raylainw nagirdwng nama? ma khobor nwngna?---TTS---ओइ जोमै! स्पेनिस रायलायनो नागिरदों नामा? मा खबर नोंना?]`
    : "\n[Constraint: Reply strictly in Bodo Devanagari script (बर' हांखो). Never output Roman script.]";

  const depth = MEMORY_DEPTH[currentPlan] || -6;
  const apiHistory = currentChatMessages.slice(depth).map((msg, index, arr) => ({
    role: msg.role === 'user' ? 'user' : 'model',
    parts: [{ text: (msg.role === 'user' && index === arr.length - 1) ? msg.text + scriptConstraint : msg.text }]
  }));

  abortController = new AbortController();
  let fullAiText = '', aiBubble = null;

  try {
    const idToken = await getAuthToken();
    const headers = { 'Content-Type': 'application/json' };
    if (idToken) headers['Authorization'] = `Bearer ${idToken}`;

    const res = await fetch(STREAM_API_URL, {
      method: 'POST',
      headers,
      signal: abortController.signal,
      body: JSON.stringify({
        plan: currentPlan,
        model: selectedModel,
        script: currentScript,
        userPersona: buildPersonaContext(),
        contents: apiHistory,
        generationConfig: {
          temperature: 0.35,
          maxOutputTokens: selectedModel === 'okafwr-2.1' ? 4000 : 1500
        }
      })
    });


    if (!res.ok) {
      if (res.status === 401) throw new Error("Session expired. Please sign in again.");
      if (res.status === 429) throw new Error("Daily limit reached. Try again tomorrow or upgrade.");
      const errData = await res.json().catch(() => null) || {};
      throw new Error(typeof errData.error?.message === 'object' ? JSON.stringify(errData.error.message) : (errData.error?.message || errData.error || `HTTP ${res.status}`));
    }

    thinking && thinking.classList.add('hidden');
    aiBubble = createBubbleElement('model');

    await processStream(res.body.getReader(), (chunk) => {
      fullAiText += chunk;
      const { displayText } = parseDualResponse(fullAiText);
      aiBubble.innerHTML = renderMarkdown(displayText);
      if (chat) chat.scrollTop = chat.scrollHeight;
    });

    if (fullAiText.trim()) {
      const { displayText, ttsText } = parseDualResponse(fullAiText);
      aiBubble.innerHTML = renderMarkdown(displayText);
      currentChatMessages.push({ role: 'model', text: displayText });
      await saveCurrentThreadToCloud();
      await persistUsageIncrement();
      attachTtsButton(aiBubble, ttsText);
    }
  } catch (err) {
    if (err.name === 'AbortError' && fullAiText.trim()) {
      const { displayText, ttsText } = parseDualResponse(fullAiText);
      aiBubble.innerHTML = renderMarkdown(displayText);
      currentChatMessages.push({ role: 'model', text: displayText });
      await saveCurrentThreadToCloud();
      await persistUsageIncrement();
      attachTtsButton(aiBubble, ttsText);
    } else {
      thinking && thinking.classList.add('hidden');
      let friendlyMsg = err.message;
      if (err.message.includes('429')) {
        friendlyMsg = currentScript === 'roman' ? 'Rate limit hit. 15s nena-nwi fin lwir.' : 'रेत लिमिट थफैबाय। 15 सेकेन्द नेनानै फिन लिर।';
      } else if (err.message.includes('high demand') || err.message.includes('503')) {
        friendlyMsg = currentScript === 'roman' ? 'Server-ao traffic baraydwng. 10s unao fin sonanai nay.' : 'सार्भार आव मानसि बारा जादों। 10 सेकेन्द उनाव फिन नाजा।';
      }
      appendMessage('model', friendlyMsg);
    }
  } finally {
    thinking && thinking.classList.add('hidden');
    setGeneratingState(false);
    abortController = null;
    input && input.focus();
  }
}

async function handleAudioSend(audioBlob, mimeType, liveMode = false) {
  if (isGenerating) return;
  const limit = DAILY_LIMITS[currentPlan] || 20;
  if (currentDailyUsage >= limit) {
    if (!currentUser) {
      alert(`You've used your ${limit} free guest messages for today. Sign in with Google for a higher daily limit.`);
      openAuthModal();
    } else {
      alert(`You reached your daily limit of ${limit} messages. Upgrade to get higher limits.`);
      upgradeModal && upgradeModal.classList.remove('hidden');
    }
    return;
  }

  const welcome = $('welcome-screen');
  if (welcome) welcome.remove();

  const userBubble = createBubbleElement('user');
  userBubble.textContent = '🎙️ Transcribing...';
  currentChatMessages.push({ role: 'user', text: '[Voice Note]' });
  setGeneratingState(true);
  thinking && thinking.classList.remove('hidden');
  if (liveMode) setLiveTalkUI('thinking');

  const base64Audio = await new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.onloadend = () => resolve(reader.result.split(',')[1]);
    reader.onerror = reject;
    reader.readAsDataURL(audioBlob);
  });

  const scriptConstraint = currentScript === 'roman'
    ? `Constraint:1. Provide the reply in natural, colloquial Roman Bodo (using 'w', 'dong', and keeping English words like 'Spanish', 'phone' as-is).2. Follow immediately with '---TTS---' on a new line, then the EXACT same sentence in Bodo Devanagari script (बर' हांखो) for speech synthesis.Example format:Oi jwmwi! Spanish raylainw nagirdwng nama? ma khobor nwngna?---TTS---ओइ जोमै! स्पेनिस रायलायनो नागिरदों नामा? मा खबर नोंना?`
    : "Reply strictly in Bodo Devanagari script (बर' हांखो). Never output Roman script.";

  const depth = MEMORY_DEPTH[currentPlan] || -6;
  const apiHistory = currentChatMessages.slice(depth).map(msg => ({
    role: msg.role === 'user' ? 'user' : 'model',
    parts: [{ text: msg.text }]
  }));

  apiHistory[apiHistory.length - 1] = {
    role: 'user',
    parts: [
      { inlineData: { mimeType, data: base64Audio } },
      { text: `1. Transcribe accurately.\n2. Formulate conversational reply as Orki.\nConstraint: ${scriptConstraint}\n\nOutput MUST strictly follow:\nTRANSCRIPTION: <exact words>\nRESPONSE: <reply>` }
    ]
  };

  abortController = new AbortController();
  let fullAiText = '', aiBubble = null;

  try {
    const idToken = await getAuthToken();
    const headers = { 'Content-Type': 'application/json' };
    if (idToken) headers['Authorization'] = `Bearer ${idToken}`;

    const res = await fetch(STREAM_API_URL, {
      method: 'POST',
      headers,
      signal: abortController.signal,
      body: JSON.stringify({
        plan: currentPlan,
        model: selectedModel,
        script: currentScript,
        userPersona: buildPersonaContext(),
        contents: apiHistory,
        generationConfig: {
          temperature: 0.35,
          maxOutputTokens: selectedModel === 'okafwr-2.1' ? 4000 : 1500
        }
      })
    });

    if (!res.ok) {
      if (res.status === 401) throw new Error("Session expired. Please sign in again.");
      if (res.status === 429) throw new Error("Daily limit reached. Try again tomorrow or upgrade.");
      const errData = await res.json().catch(() => null) || {};
      throw new Error(typeof errData.error?.message === 'object' ? JSON.stringify(errData.error.message) : (errData.error?.message || errData.error || `HTTP ${res.status}`));
    }

    thinking && thinking.classList.add('hidden');
    aiBubble = createBubbleElement('model');

    await processStream(res.body.getReader(), (chunk) => {
      fullAiText += chunk;
      if (fullAiText.includes('RESPONSE:')) {
        const parts = fullAiText.split('RESPONSE:');
        const transcript = parts[0].replace('TRANSCRIPTION:', '').trim();
        const reply = parts.slice(1).join('RESPONSE:').trimStart();
        const { displayText } = parseDualResponse(reply);
        userBubble.textContent = transcript ? `🎙️ "${transcript}"` : '🎙️ [Voice Note]';
        aiBubble.innerHTML = renderMarkdown(displayText);
        if (liveMode && liveTalkTranscript) liveTalkTranscript.textContent = displayText;
      } else if (fullAiText.includes('TRANSCRIPTION:')) {
        const liveTranscript = fullAiText.replace('TRANSCRIPTION:', '').trim();
        userBubble.textContent = liveTranscript ? `🎙️ "${liveTranscript}..."` : '🎙️ Transcribing...';
        if (liveMode && liveTalkTranscript) liveTalkTranscript.textContent = liveTranscript ? `"${liveTranscript}"` : "";
      } else {
        aiBubble.innerHTML = renderMarkdown(fullAiText);
      }
      if (chat) chat.scrollTop = chat.scrollHeight;
    });

    if (fullAiText.includes('RESPONSE:')) {
      const parts = fullAiText.split('RESPONSE:');
      const transcript = parts[0].replace('TRANSCRIPTION:', '').trim();
      const rawReply = parts.slice(1).join('RESPONSE:').trim();
      const { displayText, ttsText } = parseDualResponse(rawReply);
      aiBubble.innerHTML = renderMarkdown(displayText);
      currentChatMessages[currentChatMessages.length - 1].text = transcript || '[Voice Note]';
      currentChatMessages.push({ role: 'model', text: displayText });
      await saveCurrentThreadToCloud();
      await persistUsageIncrement();
      attachTtsButton(aiBubble, ttsText);
      if (liveMode) await speakThenResumeLiveTalk(ttsText);
    } else if (fullAiText.trim()) {
      const { displayText, ttsText } = parseDualResponse(fullAiText);
      aiBubble.innerHTML = renderMarkdown(displayText);
      currentChatMessages.push({ role: 'model', text: displayText });
      await saveCurrentThreadToCloud();
      await persistUsageIncrement();
      attachTtsButton(aiBubble, ttsText);
      if (liveMode) await speakThenResumeLiveTalk(ttsText);
    } else if (liveMode && isLiveTalkActive) {
      // Nothing came back — just listen again
      startRecording(true);
    }
  } catch (err) {
    if (err.name !== 'AbortError') {
      thinking && thinking.classList.add('hidden');
      userBubble.textContent = '🎙️ [Failed Voice Note]';
      appendMessage('model', `Voice processing error: ${err.message}`);
    }
    if (liveMode) stopLiveTalk();
  } finally {
    thinking && thinking.classList.add('hidden');
    setGeneratingState(false);
    abortController = null;
  }
}

// Plays the TTS reply through the shared player and, once it
// finishes, automatically starts listening again (live talk loop).
async function speakThenResumeLiveTalk(ttsText) {
  if (!isLiveTalkActive) return;
  const cleanText = cleanTextForTTS(ttsText);
  if (!cleanText) {
    if (isLiveTalkActive) startRecording(true);
    return;
  }

  setLiveTalkUI('speaking');
  try {
    let audioUrl = ttsAudioCache.get(cleanText);
    if (!audioUrl) {
      const res = await fetch(TTS_API_URL, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ text: cleanText })
      });
      if (!res.ok) throw new Error(`Server status ${res.status}`);
      const data = await res.json();
      if (!data.audioUrl) throw new Error("Audio URL missing from server response");
      audioUrl = data.audioUrl;
      ttsAudioCache.set(cleanText, audioUrl);
    }

    if (!currentAudio) currentAudio = new Audio();
    currentAudio.src = audioUrl;
    bindAudioToPlayer(currentAudio);
    currentAudio.onended = () => {
      audioPlayerBar && audioPlayerBar.classList.add('hidden');
      if (isLiveTalkActive) startRecording(true);
    };
    await currentAudio.play();
  } catch (err) {
    console.error("Live talk TTS error:", err);
    if (isLiveTalkActive) startRecording(true);
  }
}

// ============================================================
// AUDIO RECORDING
// ============================================================
async function startRecording(liveMode = false) {
  if (isGenerating) return;

  // Prime the shared audio player right on the tap so the browser
  // authorizes autoplay later when the TTS reply comes back.
  unlockAudio();

  try {
    // Live Talk reuses one persistent stream across turns (acquired in
    // startLiveTalk, released in stopLiveTalk) to avoid repeatedly
    // creating/tearing down audio streams, which causes popping and lag
    // on Android. Regular (non-live) mic taps still request fresh each time.
    let stream;
    if (liveMode) {
      if (!liveTalkStream || !liveTalkStream.getAudioTracks().some(t => t.readyState === 'live')) {
        liveTalkStream = await navigator.mediaDevices.getUserMedia({ audio: true });
      }
      stream = liveTalkStream;
    } else {
      stream = await navigator.mediaDevices.getUserMedia({ audio: true });
    }
    mediaRecorder = new MediaRecorder(stream);
    audioChunks = [];
    mediaRecorder.ondataavailable = (e) => {
      if (e.data && e.data.size > 0) audioChunks.push(e.data);
    };
    mediaRecorder.onstop = async () => {
      stopSilenceWatcher();
      const mimeType = mediaRecorder.mimeType.split(';')[0] || 'audio/webm';
      const audioBlob = new Blob(audioChunks, { type: mimeType });
      if (!liveMode) stream.getTracks().forEach(track => track.stop());
      if (audioBlob.size < 800) {
        if (liveMode) {
          // Nothing worth sending — just listen again instead of erroring out
          if (isLiveTalkActive) startRecording(true);
        } else {
          alert("Recording too short. Speak and tap mic again when done.");
        }
        return;
      }
      await handleAudioSend(audioBlob, mimeType, liveMode);
    };
    mediaRecorder.start();
    isRecording = true;

    if (liveMode) {
      setLiveTalkUI('listening');
      startSilenceWatcher(stream);
    } else {
      micBtn.classList.replace('bg-zinc-800', 'bg-red-600');
      micBtn.classList.replace('text-zinc-300', 'text-white');
      micBtn.classList.add('animate-pulse');
    }
  } catch {
    alert("Microphone permission denied or not supported.");
    if (liveMode) stopLiveTalk();
  }
}

function stopRecording() {
  stopSilenceWatcher();
  if (mediaRecorder && mediaRecorder.state !== 'inactive') mediaRecorder.stop();
  isRecording = false;
  if (micBtn) {
    micBtn.classList.replace('bg-red-600', 'bg-zinc-800');
    micBtn.classList.replace('text-white', 'text-zinc-300');
    micBtn.classList.remove('animate-pulse');
  }
}

// ------------------------------------------------------------
// Silence detection: auto-stops the recording ~1.2s after the
// person stops talking, so live talk needs no manual mic tap.
// ------------------------------------------------------------
function startSilenceWatcher(stream) {
  try {
    const AudioCtx = window.AudioContext || window.webkitAudioContext;
    liveTalkAudioCtx = new AudioCtx();
    const source = liveTalkAudioCtx.createMediaStreamSource(stream);
    liveTalkAnalyser = liveTalkAudioCtx.createAnalyser();
    liveTalkAnalyser.fftSize = 512;
    source.connect(liveTalkAnalyser);

    const data = new Uint8Array(liveTalkAnalyser.frequencyBinCount);
    const SILENCE_THRESHOLD = 14; // avg amplitude below this = quiet (slightly higher to ignore soft room hums)
    const SILENCE_DURATION = 800; // ms of quiet before auto-stop (cut from 1200ms for faster handoffs)
    const MIN_SPEECH_MS = 600; // ignore silence before the person has said anything
    let hasHeardSpeech = false;
    const startedAt = Date.now();

    const tick = () => {
      if (!isRecording || !liveTalkAnalyser) return;
      liveTalkAnalyser.getByteFrequencyData(data);
      const avg = data.reduce((a, b) => a + b, 0) / data.length;

      // React the orb to vocal energy: scales smoothly between 1.0x and ~1.35x
      if (liveTalkOrb && isRecording) {
        const scale = Math.min(1.35, 1 + (avg / 60));
        liveTalkOrb.style.transform = `scale(${scale.toFixed(2)})`;
      }

      if (avg > SILENCE_THRESHOLD) {
        hasHeardSpeech = true;
        clearTimeout(liveTalkSilenceTimer);
        liveTalkSilenceTimer = null;
      } else if (hasHeardSpeech && !liveTalkSilenceTimer && Date.now() - startedAt > MIN_SPEECH_MS) {
        liveTalkSilenceTimer = setTimeout(() => {
          if (isRecording) stopRecording();
        }, SILENCE_DURATION);
      }
      if (isRecording) requestAnimationFrame(tick);
    };
    requestAnimationFrame(tick);
  } catch (e) {
    console.warn("Silence detection unavailable:", e);
  }
}

function stopSilenceWatcher() {
  clearTimeout(liveTalkSilenceTimer);
  liveTalkSilenceTimer = null;
  liveTalkAnalyser = null;
  if (liveTalkOrb) liveTalkOrb.style.transform = '';
  if (liveTalkAudioCtx) {
    liveTalkAudioCtx.close().catch(() => {});
    liveTalkAudioCtx = null;
  }
}

// ------------------------------------------------------------
// Live Talk mode: tap once to start a hands-free loop of
// listen -> send -> play reply -> listen again.
// ------------------------------------------------------------
function setLiveTalkUI(state) {
  if (!liveTalkBtn) return;

  // Footer button state (kept for consistency if overlay somehow isn't present)
  if (state === 'listening') {
    liveTalkBtn.classList.replace('bg-zinc-800', 'bg-red-600');
    liveTalkBtn.classList.replace('text-zinc-300', 'text-white');
    liveTalkPulse && liveTalkPulse.classList.remove('hidden');
    liveTalkBtn.title = "Listening… tap to end Live Talk";
  } else if (state === 'thinking' || state === 'speaking') {
    liveTalkBtn.classList.remove('bg-red-600');
    liveTalkBtn.classList.add('bg-amber-500', 'text-white');
    liveTalkPulse && liveTalkPulse.classList.add('hidden');
    liveTalkBtn.title = state === 'speaking' ? "Orki is speaking… tap to end Live Talk" : "Thinking… tap to end Live Talk";
  } else {
    liveTalkBtn.classList.remove('bg-red-600', 'bg-amber-500', 'text-white');
    liveTalkBtn.classList.add('bg-zinc-800', 'text-zinc-300');
    liveTalkPulse && liveTalkPulse.classList.add('hidden');
    liveTalkBtn.title = "Live Talk";
  }

  // Full-screen overlay orb + status pill
  if (!liveTalkOrb || !liveTalkStatusPill || !liveTalkRing) return;

  if (state === 'listening') {
    liveTalkStatusPill.textContent = "Listening";
    liveTalkStatusPill.className = "text-[11px] font-semibold px-3 py-1 rounded-full bg-emerald-500/20 text-emerald-300 transition-colors duration-300";
    liveTalkOrb.style.background = "radial-gradient(circle at 35% 30%, #6ee7b7, #10b981 45%, #047857 100%)";
    liveTalkOrb.style.boxShadow = "0 0 60px 10px rgba(16,185,129,0.45)";
    liveTalkOrb.classList.add('animate-pulse');
    liveTalkRing.className = "absolute inset-0 rounded-full border border-emerald-400/40 transition-all duration-500 scale-100";
  } else if (state === 'thinking') {
    liveTalkStatusPill.textContent = "Thinking";
    liveTalkStatusPill.className = "text-[11px] font-semibold px-3 py-1 rounded-full bg-amber-500/20 text-amber-300 transition-colors duration-300";
    liveTalkOrb.style.background = "radial-gradient(circle at 35% 30%, #fde68a, #f59e0b 45%, #b45309 100%)";
    liveTalkOrb.style.boxShadow = "0 0 60px 10px rgba(245,158,11,0.45)";
    liveTalkOrb.classList.remove('animate-pulse');
    liveTalkRing.className = "absolute inset-0 rounded-full border border-amber-400/40 transition-all duration-500 scale-95 animate-spin";
    liveTalkRing.style.animationDuration = "3s";
  } else if (state === 'speaking') {
    liveTalkStatusPill.textContent = "Speaking";
    liveTalkStatusPill.className = "text-[11px] font-semibold px-3 py-1 rounded-full bg-sky-500/20 text-sky-300 transition-colors duration-300";
    liveTalkOrb.style.background = "radial-gradient(circle at 35% 30%, #bae6fd, #0ea5e9 45%, #075985 100%)";
    liveTalkOrb.style.boxShadow = "0 0 70px 14px rgba(14,165,233,0.5)";
    liveTalkOrb.classList.remove('animate-pulse');
    liveTalkOrb.classList.add('animate-pulse');
    liveTalkRing.className = "absolute inset-0 rounded-full border border-sky-400/50 transition-all duration-500 scale-110";
    liveTalkRing.style.animationDuration = "";
  }
}

async function startLiveTalk() {
  isLiveTalkActive = true;
  playLiveTalkOpenSound();
  if (liveTalkOverlay) {
    liveTalkOverlay.classList.remove('hidden');
    liveTalkOverlay.classList.add('flex');
  }
  if (liveTalkTranscript) liveTalkTranscript.textContent = "";

  // Acquire the mic stream once for the whole live-talk session.
  try {
    liveTalkStream = await navigator.mediaDevices.getUserMedia({ audio: true });
  } catch {
    alert("Microphone permission denied or not supported.");
    isLiveTalkActive = false;
    if (liveTalkOverlay) {
      liveTalkOverlay.classList.add('hidden');
      liveTalkOverlay.classList.remove('flex');
    }
    return;
  }

  startRecording(true);
}

function stopLiveTalk() {
  isLiveTalkActive = false;
  stopSilenceWatcher();
  if (isRecording) stopRecording();
  if (currentAudio && !currentAudio.paused) currentAudio.pause();
  if (liveTalkStream) {
    liveTalkStream.getTracks().forEach(t => t.stop());
    liveTalkStream = null;
  }
  setLiveTalkUI('idle');
  if (liveTalkOrb) {
    liveTalkOrb.classList.remove('animate-pulse');
    liveTalkOrb.style.transform = '';
  }
  if (liveTalkRing) liveTalkRing.classList.remove('animate-spin');
  if (liveTalkTranscript) liveTalkTranscript.textContent = "";
  if (liveTalkOverlay) {
    liveTalkOverlay.classList.add('hidden');
    liveTalkOverlay.classList.remove('flex');
  }
}

on('live-talk-btn', 'click', () => {
  if (isLiveTalkActive) {
    stopLiveTalk();
  } else {
    startLiveTalk();
  }
});

on('live-talk-end-btn', 'click', () => stopLiveTalk());

// ------------------------------------------------------------
// Tap-to-interrupt / force-send: tapping the orb while Orki is
// speaking barges in and starts listening immediately; tapping
// it while you're speaking force-sends without waiting on the
// silence timer.
// ------------------------------------------------------------
on('live-talk-orb', 'click', () => {
  if (!isLiveTalkActive) return;

  // 1. Interrupt Orki if it's talking
  if (currentAudio && !currentAudio.paused) {
    currentAudio.pause();
    currentAudio.currentTime = 0;
    startRecording(true);
    return;
  }

  // 2. Force-send speech immediately instead of waiting for silence timer
  if (isRecording) {
    stopRecording();
  }
});

// ============================================================
// FIRESTORE & HISTORY
// ============================================================
async function saveCurrentThreadToCloud() {
  if (isIncognito || !currentUser || !db || currentChatMessages.length === 0) return;
  const firstPrompt = currentChatMessages.find(m => m.role === 'user')?.text || "New Conversation";
  const threadTitle = firstPrompt.length > 28 ? firstPrompt.slice(0, 28) + '...' : firstPrompt;
  try {
    const threadCollection = db.collection("users").doc(currentUser.uid).collection("threads");
    if (!currentChatId) {
      const docRef = await threadCollection.add({
        title: threadTitle,
        messages: currentChatMessages,
        updatedAt: firebase.firestore.FieldValue.serverTimestamp()
      });
      currentChatId = docRef.id;
    } else {
      await threadCollection.doc(currentChatId).set({
        title: threadTitle,
        messages: currentChatMessages,
        updatedAt: firebase.firestore.FieldValue.serverTimestamp()
      }, { merge: true });
    }
    await loadUserThreads(currentUser.uid);
  } catch (e) {
    console.error("Failed to sync thread:", e);
  }
}

async function loadUserThreads(uid) {
  if (!db) return;
  try {
    const snap = await db.collection("users").doc(uid).collection("threads").orderBy("updatedAt", "desc").limit(20).get();
    cachedThreads = snap.docs.map(doc => ({ id: doc.id, ...doc.data() }));
    renderHistorySidebar();
  } catch (e) {
    console.warn("Error fetching threads:", e);
  }
}

function renderHistorySidebar() {
  if (!historyList) return;
  if (!currentUser) {
    historyList.innerHTML = `<p class="text-zinc-500 px-2 py-2 text-[11px]">Sign in to sync history</p>`;
    clearAllBtn && clearAllBtn.classList.add('hidden');
    return;
  }
  if (cachedThreads.length === 0) {
    historyList.innerHTML = `<p class="text-zinc-500 px-2 py-2 text-[11px]">No conversations yet</p>`;
    clearAllBtn && clearAllBtn.classList.add('hidden');
    return;
  }
  clearAllBtn && clearAllBtn.classList.remove('hidden');
  historyList.innerHTML = '';
  cachedThreads.forEach(thread => {
    const isActive = thread.id === currentChatId;
    const row = document.createElement('div');
    row.className = `group flex items-center justify-between p-1.5 rounded-lg text-[12px] gap-1 transition ${isActive ? 'bg-zinc-800 text-white font-medium' : 'text-zinc-300 hover:bg-zinc-800/60'}`;
    const btn = document.createElement('button');
    btn.type = "button";
    btn.className = "flex-1 text-left truncate cursor-pointer py-0.5 px-1";
    btn.textContent = thread.title || "Conversation";
    btn.onclick = () => openThread(thread);
    const delBtn = document.createElement('button');
    delBtn.type = "button";
    delBtn.className = "text-zinc-500 hover:text-red-400 p-1 rounded hover:bg-zinc-700/50 opacity-70 group-hover:opacity-100 transition cursor-pointer shrink-0";
    delBtn.title = "Delete conversation";
    delBtn.innerHTML = trashIcon;
    delBtn.onclick = async (e) => {
      e.stopPropagation();
      try {
        await db.collection("users").doc(currentUser.uid).collection("threads").doc(thread.id).delete();
        if (currentChatId === thread.id) startNewChat();
        else await loadUserThreads(currentUser.uid);
      } catch (err) {
        console.error("Delete failed:", err);
      }
    };
    row.appendChild(btn);
    row.appendChild(delBtn);
    historyList.appendChild(row);
  });
}

function openThread(thread) {
  if (isGenerating && abortController) abortController.abort();
  currentChatId = thread.id;
  currentChatMessages = Array.isArray(thread.messages) ? [...thread.messages] : [];
  if (chat) {
    chat.innerHTML = '';
    if (currentChatMessages.length === 0) chat.appendChild(createWelcomeScreen());
    else currentChatMessages.forEach(msg => appendMessage(msg.role, msg.text));
  }
  renderHistorySidebar();
  toggleDrawer(false);
}

// ============================================================
// PAYMENT & SETTINGS
// ============================================================
function initiatePayment(planTier, amountPaise) {
  if (!currentUser) {
    openAuthModal();
    return;
  }
  upgradeModal && upgradeModal.classList.add('hidden');
  const options = {
    key: RAZORPAY_KEY_ID,
    amount: amountPaise,
    currency: "INR",
    name: "Orki AI",
    description: `${planTier} Plan (${selectedCycle})`,
    prefill: {
      email: currentUser ? currentUser.email : "",
      contact: "9999999999"
    },
    theme: {
      color: planTier === "Pro" ? "#f59e0b" : "#059669"
    },
    handler: async function (response) {
      try {
        // NOTE: In production, verify razorpay_signature on Supabase server before updating plan
        const daysToAdd = selectedCycle === 'yearly' ? 365 : selectedCycle === 'monthly' ? 30 : 7;
        const expiresAt = new Date(Date.now() + daysToAdd * 24 * 60 * 60 * 1000);
        await db.collection("users").doc(currentUser.uid).set({
          plan: planTier,
          cycle: selectedCycle,
          expiresAt: expiresAt,
          updatedAt: firebase.firestore.FieldValue.serverTimestamp()
        }, { merge: true });

        currentPlan = planTier;
        userPlan.textContent = `Plan: ${planTier}`;
        userPlan.className = `text-[11px] font-semibold ${planTier === "Pro" ? 'text-amber-400' : 'text-emerald-400'}`;
        upgradeBtn.textContent = `${planTier} Active`;
        upgradeBtn.disabled = true;
        updateModelLockUI();
        updateUsageUI();
        alert(`Success! You are now subscribed to ${planTier} until ${expiresAt.toLocaleDateString()}.`);
      } catch (err) {
        alert("Activation failed: " + err.message);
      }
    }
  };
  new Razorpay(options).open();
}

// ============================================================
// EVENT BINDINGS
// ============================================================
on('mic-btn', 'click', () => {
  if (isLiveTalkActive) {
    stopLiveTalk();
    return;
  }
  isRecording ? stopRecording() : startRecording();
});

on('menu-btn', 'click', () => toggleDrawer(true));
on('close-drawer', 'click', () => toggleDrawer(false));
on('drawer-backdrop', 'click', () => toggleDrawer(false));
on('new-chat-btn', 'click', startNewChat);

on('incognito-btn', 'click', () => {
  isIncognito = !isIncognito;
  updateIncognitoUI();
  startNewChat();
});

on('model-select-btn', 'click', (e) => {
  e.stopPropagation();
  modelDropdown && modelDropdown.classList.toggle('hidden');
});

document.addEventListener('click', () => modelDropdown && !modelDropdown.classList.contains('hidden') && modelDropdown.classList.add('hidden'));

on('select-orki', 'click', () => {
  selectedModel = 'orki-3.0';
  if (currentModelDisplay) {
    currentModelDisplay.textContent = 'Orki 3.0';
    currentModelDisplay.className = 'text-zinc-200';
  }
  modelDropdown && modelDropdown.classList.add('hidden');
});

on('select-okafwr', 'click', () => {
  if (currentPlan !== 'Pro') {
    modelDropdown && modelDropdown.classList.add('hidden');
    upgradeModal && upgradeModal.classList.remove('hidden');
    alert("Okafwr 2.1 requires an active Pro subscription.");
    return;
  }
  selectedModel = 'okafwr-2.1';
  if (currentModelDisplay) {
    currentModelDisplay.textContent = 'Okafwr 2.1 ⚡';
    currentModelDisplay.className = 'text-amber-400 font-bold';
  }
  modelDropdown && modelDropdown.classList.add('hidden');
});

on('cycle-weekly', 'click', () => { selectedCycle = 'weekly'; updatePricingUI(); });
on('cycle-monthly', 'click', () => { selectedCycle = 'monthly'; updatePricingUI(); });
on('cycle-yearly', 'click', () => { selectedCycle = 'yearly'; updatePricingUI(); });

on('upgrade-btn', 'click', () => {
  if (!currentUser) {
    openAuthModal();
    return;
  }
  upgradeModal && upgradeModal.classList.remove('hidden');
  toggleDrawer(false);
});

on('close-upgrade', 'click', () => upgradeModal && upgradeModal.classList.add('hidden'));
on('buy-plus-btn', 'click', () => initiatePayment("Plus", PRICING[selectedCycle].plusPaise));
on('buy-pro-btn', 'click', () => initiatePayment("Pro", PRICING[selectedCycle].proPaise));

on('open-settings', 'click', () => {
  toggleDrawer(false);
  if (personaInput) personaInput.value = userPersona;
  if (usernameInput) usernameInput.value = userName;
  updateScriptUI();
  updateUiLangUI();
  settingsModal && settingsModal.classList.remove('hidden');
});

on('close-settings', 'click', () => settingsModal && settingsModal.classList.add('hidden'));
on('opt-deva', 'click', () => { currentScript = 'deva'; updateScriptUI(); });
on('opt-rom', 'click', () => { currentScript = 'roman'; updateScriptUI(); });

on('opt-ui-deva', 'click', () => { uiLanguage = 'deva'; updateUiLangUI(); applyUILanguage(uiLanguage); });
on('opt-ui-rom', 'click', () => { uiLanguage = 'roman'; updateUiLangUI(); applyUILanguage(uiLanguage); });
on('opt-ui-en', 'click', () => { uiLanguage = 'en'; updateUiLangUI(); applyUILanguage(uiLanguage); });

on('save-settings', 'click', () => {
  userPersona = personaInput ? personaInput.value.trim() : '';
  userName = usernameInput ? usernameInput.value.trim() : '';
  safeSet('arki_script', currentScript);
  safeSet('arki_ui_lang', uiLanguage);
  safeSet('arki_persona', userPersona);
  safeSet('arki_username', userName);
  settingsModal && settingsModal.classList.add('hidden');
});

on('clear-all-btn', 'click', async () => {
  if (!currentUser || !db || !confirm("Clear all conversations?")) return;
  try {
    const snap = await db.collection("users").doc(currentUser.uid).collection("threads").get();
    await Promise.all(snap.docs.map(d => d.ref.delete()));
    startNewChat();
    await loadUserThreads(currentUser.uid);
  } catch (err) {
    console.error("Clear all failed:", err);
  }
});

if (input) {
  input.addEventListener('input', function () {
    this.style.height = 'auto';
    this.style.height = Math.min(this.scrollHeight, 112) + 'px';
  });
  input.addEventListener('keydown', function (e) {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault();
      handleSend();
    }
  });
}

if (form) {
  form.onsubmit = (e) => {
    e.preventDefault();
    handleSend();
  };
}

// ============================================================
// FIREBASE INIT & GOOGLE AUTH
// ============================================================
try {
  if (window.firebase) {
    firebase.initializeApp(firebaseConfig);
    auth = firebase.auth();
    db = firebase.firestore();

    // Catch returning redirect from Google
    auth.getRedirectResult().then((result) => {
      if (result && result.user) {
        if (authModal) authModal.classList.add('hidden');
      }
    }).catch((err) => {
      console.error("Redirect return error:", err);
      alert("Login error: " + err.message);
    });

    auth.onAuthStateChanged(async (user) => {
      currentUser = user;
      const today = getTodayString();

      if (user) {
        alert("Firebase confirmed login: " + user.email); // <--- DEBUG ALERT
        if (authModal) authModal.classList.add('hidden');   // <--- FORCE HIDE MODAL

        userDisplay && (userDisplay.textContent = user.displayName || user.email.split('@')[0]);
        syncStatus && (syncStatus.textContent = "Synced to Cloud");
        authActionBtn && (authActionBtn.textContent = "Logout");
        upgradeBtn && upgradeBtn.classList.remove('hidden');

        if (input) {
          input.disabled = false;
          input.placeholder = "Message Orki...";
        }
        if (sendBtn) sendBtn.disabled = false;
        if (micBtn) micBtn.disabled = false;
        if (liveTalkBtn) liveTalkBtn.disabled = false;

        try {
          const doc = await db.collection("users").doc(user.uid).get();
          if (doc.exists) {
            const data = doc.data();
            const now = new Date();
            const expiresAt = data.expiresAt ? data.expiresAt.toDate() : null;
            if (expiresAt && expiresAt < now) {
              currentPlan = "Free";
              await db.collection("users").doc(user.uid).update({ plan: "Free" });
            } else {
              currentPlan = data.plan || "Free";
            }
            const usageData = data.dailyUsage || {};
            if (usageData.date !== today) {
              currentDailyUsage = 0;
              await db.collection("users").doc(user.uid).set({ dailyUsage: { date: today, count: 0 } }, { merge: true });
            } else {
              currentDailyUsage = usageData.count || 0;
            }
          } else {
            currentPlan = "Free";
            currentDailyUsage = 0;
          }
        } catch {
          currentPlan = "Free";
          currentDailyUsage = 0;
        }

        if (userPlan) {
          userPlan.textContent = `Plan: ${currentPlan}`;
          userPlan.className = `text-[11px] font-semibold ${currentPlan === "Pro" ? 'text-amber-400' : 'text-emerald-400'}`;
          if (upgradeBtn) {
            upgradeBtn.textContent = currentPlan === "Pro" ? "Pro Active" : currentPlan === "Plus" ? "Plus Active" : "Upgrade";
            upgradeBtn.disabled = currentPlan === "Pro";
          }
        }
        updateModelLockUI();
        updateUsageUI();
        loadUserThreads(user.uid);
      } else {
        userDisplay && (userDisplay.textContent = "Guest User");
        syncStatus && (syncStatus.textContent = "Local Session (not saved)");
        authActionBtn && (authActionBtn.textContent = "Login");
        if (userPlan) {
          userPlan.textContent = "Plan: Guest";
          userPlan.className = "text-[11px] font-semibold text-zinc-400";
        }
        upgradeBtn && upgradeBtn.classList.add('hidden');
        currentPlan = "Guest";
        selectedModel = 'orki-3.0';
        if (currentModelDisplay) {
          currentModelDisplay.textContent = 'Orki 3.0';
          currentModelDisplay.className = 'text-zinc-200';
        }

        // Guest quota lives in localStorage only — no cloud sync, resets daily
        try {
          const guestUsage = JSON.parse(safeGet('arki_guest_usage', 'null')) || {};
          currentDailyUsage = guestUsage.date === today ? (guestUsage.count || 0) : 0;
        } catch {
          currentDailyUsage = 0;
        }

        updateModelLockUI();
        updateUsageUI();
        cachedThreads = [];

        // Guests can chat freely — only cloud sync/history/upgrades require sign-in
        if (input) {
          input.disabled = false;
          input.placeholder = "Message Orki... (sign in to save history)";
        }
        if (sendBtn) sendBtn.disabled = false;
        if (micBtn) micBtn.disabled = false;
        if (liveTalkBtn) liveTalkBtn.disabled = false;

        renderHistorySidebar();
      }
    });
  }
} catch (e) {
  console.warn("Firebase restricted:", e);
}

on('auth-action-btn', 'click', () => {
  if (currentUser && auth) {
    auth.signOut();
  } else {
    openAuthModal();
    toggleDrawer(false);
  }
});

on('auth-close-btn', 'click', () => authModal && authModal.classList.add('hidden'));

// Google Auth Handler (Redirect mode for mobile reliability)
on('auth-google-btn', 'click', async () => {
  if (!auth) {
    alert("Firebase not ready. Please wait a second and try again.");
    return;
  }
  const provider = new firebase.auth.GoogleAuthProvider();
  provider.setCustomParameters({ prompt: 'select_account' });

  try {
    // Navigates the entire browser tab cleanly — no dropped popups
    await auth.signInWithRedirect(provider);
  } catch (err) {
    alert("Redirect trigger error: " + err.message);
  }
});

// ============================================================
// INIT
// ============================================================
// Guests can chat right away — Firebase auth state resolves shortly
// after and will upgrade the UI to a signed-in view if applicable.
currentPlan = "Guest";
try {
  const guestUsage = JSON.parse(safeGet('arki_guest_usage', 'null')) || {};
  currentDailyUsage = guestUsage.date === getTodayString() ? (guestUsage.count || 0) : 0;
} catch {
  currentDailyUsage = 0;
}
if (input) {
  input.disabled = false;
  input.placeholder = "Message Orki... (sign in to save history)";
}
if (sendBtn) sendBtn.disabled = false;
if (micBtn) micBtn.disabled = false;
if (liveTalkBtn) liveTalkBtn.disabled = false;

updateScriptUI();
updateUiLangUI();
updatePricingUI();
updateUsageUI();
updateIncognitoUI();
applyUILanguage(uiLanguage);

// ============================================================
// EDGE FUNCTION WARM-UP PING
// ============================================================
function warmUpEdgeFunctions() {
  const targets = [STREAM_API_URL, TTS_API_URL];

  targets.forEach(url => {
    fetch(url, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ ping: true, warmup: true })
    }).catch(() => {}); // Catch silently; all we care about is forcing Deno to spin up
  });
}

// 1. Wake them up immediately on page load
warmUpEdgeFunctions();

// 2. Keep containers warm every 4 minutes while the tab is open
setInterval(warmUpEdgeFunctions, 4 * 60 * 1000);