import { S2sWsRealtimeClient } from "./s2s/s2s-ws-client.js";
import { AvatarStage, AVATAR_MOODS, AVATAR_GESTURES } from "./avatar.js";
import { smartNormalize, prepareForTTS } from "./viNumberFix.js";

const VOICES = [
  "Aiden", "Ryan", "Dylan", "Eric",
  "Ono_Anna", "Serena", "Sohee", "Uncle_Fu", "Vivian",
];
const DEFAULT_VOICE = "Sohee";

// ── News fetching ───────────────────────────────────────────────────────
async function getHotNews(page = 1, pageSize = 10) {
  let items = [];
  try {
    const resp = await fetch(`/api/news/hot?page=${page}&pageSize=${pageSize}`);
    if (resp.ok) {
      const data = await resp.json();
      if (data.items && data.items.length > 0) {
        items = data.items;
        newsHasMore = data.hasMore || false;
      }
    }
  } catch (e) { console.warn("News API failed:", e); }
  return items;
}

const DEFAULT_INSTRUCTIONS = [
  "You are a friendly voice assistant with a visible, human-like 3D avatar.",
  "CRITICAL: Always respond in the SAME LANGUAGE that the user writes or speaks.",
  "If Vietnamese, respond in Vietnamese. If English, respond in English.",
  "When Vietnamese: write dates as 'ngày 9 tháng 7 năm 2026' (NOT '9/7/2026'),",
  "CRITICAL: When speaking Vietnamese, always write numbers as Vietnamese words (e.g. 'ba mươi lăm' not '35'). This ensures the TTS voice reads them correctly.",
  "Keep replies short, natural, warm. Never list-like.",
  "You can control avatar body with tools: set_mood, make_hand_gesture, make_facial_expression. Use them naturally.",
  "NEVER guess. Use search_web or search_wikipedia for ANY factual question.",
  "Never mention tools or that you control an avatar.",
  "Source links should be formatted as popup links with <a href> tags.",
].join(" ");

const STORAGE_KEYS = {
  voice: "avatar.voice", avatar: "avatar.model", instructions: "avatar.instructions",
  directUrl: "avatar.directUrl", subtitles: "avatar.subtitles",
};

const TOOL_DEFS = [
  { type: "function", name: "set_mood", description: "Change your avatar's overall mood/emotional state.", parameters: { type: "object", properties: { mood: { type: "string", enum: AVATAR_MOODS } }, required: ["mood"] } },
  { type: "function", name: "make_hand_gesture", description: "Make a hand gesture with your avatar.", parameters: { type: "object", properties: { gesture: { type: "string", enum: AVATAR_GESTURES } }, required: ["gesture"] } },
  { type: "function", name: "make_facial_expression", description: "Make a quick facial expression, given as a single face emoji.", parameters: { type: "object", properties: { emoji: { type: "string" } }, required: ["emoji"] } },
  { type: "function", name: "get_current_datetime", description: "Get current date and time.", parameters: { type: "object", properties: {} } },
  { type: "function", name: "search_wikipedia", description: "Search Wikipedia for a topic.", parameters: { type: "object", properties: { query: { type: "string" } }, required: ["query"] } },
  { type: "function", name: "search_web", description: "Search the web for current info.", parameters: { type: "object", properties: { query: { type: "string" } }, required: ["query"] } },
];

// ── DOM elements ─────────────────────────────────────────────────────────
const $ = (sel) => document.querySelector(sel);
const stageNode = $("#stage");
const mainBtn = $("#main-btn");
const mainBtnLabel = $("#main-btn-label");
const muteBtn = $("#mute-btn");
const textModeBtn = $("#text-mode-btn");
const newsToggleFooter = $("#news-toggle-footer");
const caption = $("#caption");
const subtitles = $("#subtitles");
const loading = $("#loading");
const settingsBtn = $("#settings-btn");
const settingsDialog = $("#settings");
const inputVoice = $("#voice");
const inputInstructions = $("#instructions");
const inputDirectUrl = $("#direct-url");
const inputSubtitles = $("#subtitles-toggle");
const directUrlRow = $("#direct-url-row");
const textChat = $("#text-chat");
const chatHeader = $("#chat-header");
const chatMessages = $("#chat-messages");
const chatInput = $("#chat-input");
const chatSendBtn = $("#chat-send-btn");
const chatCloseBtn = $("#chat-close-btn");
const chatResizeHandle = $("#chat-resize-handle");
const chatAvatarSelect = $("#chat-avatar-select");
const settingsAvatarSelect = $("#settings-avatar-select");
const newsPanel = $("#news-panel");
const newsList = $("#news-list");
const newsListContainer = $("#news-list-container");
const newsCloseBtn = $("#news-close-btn");
const newsToggleBtn = $("#news-toggle-btn");
const newsChevronUp = $("#news-chevron-up");
const newsChevronDown = $("#news-chevron-down");
const newsLoadMoreBtn = $("#news-load-more");

// ── State ───────────────────────────────────────────────────────────────
const stage = new AvatarStage(stageNode);
let client = null;
let muted = false;
let subtitleTimer = 0;
let textMode = false;
let config = { lb: false, allowDirect: true };
let avatarList = [];
let sessionInProgress = false;
let autoGreetingSent = false;
let preFetchedNews = [];
let latestNewsUrl = null;
let latestNewsSource = null;
let newsCollapsed = false;
let newsPage = 1;
const NEWS_PAGE_SIZE = 10;
let newsLoading = false;
let newsHasMore = true;

function loadSettings() {
  return {
    voice: localStorage.getItem(STORAGE_KEYS.voice) || DEFAULT_VOICE,
    avatar: localStorage.getItem(STORAGE_KEYS.avatar) || "vuong.glb",
    instructions: localStorage.getItem(STORAGE_KEYS.instructions) || "",
    directUrl: localStorage.getItem(STORAGE_KEYS.directUrl) || "",
    subtitles: localStorage.getItem(STORAGE_KEYS.subtitles) === "1",
  };
}
let settings = loadSettings();

function saveSettings() {
  localStorage.setItem(STORAGE_KEYS.voice, settings.voice);
  localStorage.setItem(STORAGE_KEYS.avatar, settings.avatar);
  localStorage.setItem(STORAGE_KEYS.instructions, settings.instructions);
  localStorage.setItem(STORAGE_KEYS.directUrl, settings.directUrl);
  localStorage.setItem(STORAGE_KEYS.subtitles, settings.subtitles ? "1" : "0");
}

function getSourceName(hostname) {
  const name = hostname.replace(/^www\./, "").toLowerCase();
  const known = {
    "vnexpress.net": "VnExpress",
    "dantri.com.vn": "Dân trí",
    "tuoitre.vn": "Tuổi Trẻ",
    "thanhnien.vn": "Thanh Niên",
    "vietnamnet.vn": "VietNamNet",
    "zingnews.vn": "ZingNews",
    "cafef.vn": "CafeF",
    "genk.vn": "GenK",
    "kenh14.vn": "Kênh 14",
    "afamily.vn": "Afamily",
    "plo.vn": "PLO",
    "vtc.vn": "VTC",
  };
  return known[name] || name;
}

// Format date/time in Vietnamese
function formatDateTimeVN(date) {
  const weekdays = ["Chủ Nhật", "Thứ Hai", "Thứ Ba", "Thứ Tư", "Thứ Năm", "Thứ Sáu", "Thứ Bảy"];
  const months = ["tháng 1", "tháng 2", "tháng 3", "tháng 4", "tháng 5", "tháng 6",
    "tháng 7", "tháng 8", "tháng 9", "tháng 10", "tháng 11", "tháng 12"];
  
  const day = date.getDate();
  const month = months[date.getMonth()];
  const year = date.getFullYear();
  const weekday = weekdays[date.getDay()];
  const hours = date.getHours().toString().padStart(2, '0');
  const minutes = date.getMinutes().toString().padStart(2, '0');
  
  return { 
    dateStr: `${weekday}, ngày ${day} ${month} năm ${year}`,
    timeStr: `${hours}:${minutes}`
  };
}

function effectiveInstructions(newsItems) {
  const now = new Date();
  const { dateStr, timeStr } = formatDateTimeVN(now);
  const dateLine = `Hôm nay là ${dateStr}. Bây giờ là ${timeStr}.`;
  const extra = settings.instructions.trim();
  const introLine = "Tôi tên là Vương đến V.AI STUDIO.";
  
  let newsInst = "";
  if (newsItems && newsItems.length > 0) {
    const topNews = newsItems[0];
    const sourceName = getSourceName(new URL(topNews.link).hostname);
    newsInst = `\n\nWhen you start the conversation, greet the user naturally with this EXACT format:\n"${introLine} ${dateStr}. ${timeStr}.\nTin HOT nhất hôm nay: ${topNews.title} (nguồn ${sourceName})"\nInclude the full title and source name in parentheses. After greeting, offer to help with questions.`;
  } else {
    newsInst = `\n\nWhen you start the conversation, greet the user naturally with this EXACT format:\n"${introLine} ${dateStr}. ${timeStr}."\nThen offer to help with questions.`;
  }
  
  const base = `${dateLine}\n\n${DEFAULT_INSTRUCTIONS}${newsInst}`;
  return extra ? `${base}\n\nAdditional user instructions:\n${extra}` : base;
}

// ── News Panel ─────────────────────────────────────────────────────────
function toggleNewsPanel() {
  if (!newsPanel) return;
  
  if (newsPanel.hidden) {
    newsPanel.hidden = false;
    newsToggleFooter?.classList.add("active");
    loadNewsPage(1, true);
  } else {
    newsPanel.hidden = true;
    newsToggleFooter?.classList.remove("active");
  }
}

function toggleNewsCollapse() {
  if (!newsPanel) return;
  
  newsCollapsed = !newsCollapsed;
  newsPanel.classList.toggle("collapsed", newsCollapsed);
  
  if (newsChevronUp && newsChevronDown) {
    newsChevronUp.hidden = newsCollapsed;
    newsChevronDown.hidden = !newsCollapsed;
  }
}

async function loadNewsPage(page = 1, reset = false) {
  if (newsLoading) return;
  newsLoading = true;
  
  if (newsLoadMoreBtn) {
    newsLoadMoreBtn.textContent = "Đang tải...";
    newsLoadMoreBtn.disabled = true;
  }
  
  try {
    const items = await getHotNews(page);
    
    if (reset && newsList) {
      newsList.innerHTML = "";
      preFetchedNews = [];
    }
    
    if (items.length > 0) {
      preFetchedNews = [...preFetchedNews, ...items];
      appendNewsItems(items);
      newsPage = page;
    }
    
    if (newsLoadMoreBtn) {
      newsLoadMoreBtn.hidden = !newsHasMore;
      newsLoadMoreBtn.textContent = "Xem thêm tin tức ↓";
      newsLoadMoreBtn.disabled = false;
    }
  } catch (e) {
    console.warn("Failed to load news page:", e);
    if (newsLoadMoreBtn) {
      newsLoadMoreBtn.textContent = "Lỗi tải tin. Thử lại ↓";
      newsLoadMoreBtn.disabled = false;
    }
  }
  
  newsLoading = false;
}

function appendNewsItems(items) {
  if (!newsList) return;
  
  items.forEach((item, idx) => {
    const newsItem = document.createElement("div");
    newsItem.className = "news-item";
    
    const globalIdx = preFetchedNews.length - items.length + idx + 1;
    
    let imageHtml = "";
    if (item.image) {
      imageHtml = `<img class="news-item-image" src="${item.image}" alt="" loading="lazy" onerror="this.style.display='none'" />`;
    }
    
    newsItem.innerHTML = `
      ${imageHtml}
      <div class="news-item-content">
        <span class="news-index">${globalIdx}.</span>
        <span class="news-title">${item.title}</span>
        <span class="news-source">(${item.source})</span>
      </div>
    `;
    
    newsItem.addEventListener("click", () => {
      summarizeArticle(item.link, item.title);
    });
    
    newsList.appendChild(newsItem);
  });
}

async function summarizeArticle(url, title) {
  const summaryText = `Hãy tóm tắt ngắn gọn và đầy đủ nhất nội dung bài viết này: "${title}" (${url})`;
  
  if (!client || !sessionInProgress) {
    void startTextSession(summaryText);
    return;
  }
  
  addChatMessage("user", `📰 ${title}`);
  client.sendUserText(summaryText);
  client.requestResponse();
}

// ── Avatar list ─────────────────────────────────────────────────────────
async function fetchAvatarList() {
  try { 
    const resp = await fetch("/api/avatars"); 
    if (resp.ok) avatarList = (await resp.json()).avatars || []; 
  } catch {}
}

function populateAvatarSelects(selectedName) {
  for (const sel of [chatAvatarSelect, settingsAvatarSelect]) {
    sel.innerHTML = "";
    const def = document.createElement("option"); 
    def.value = ""; 
    def.textContent = "(Default - Brunette)"; 
    sel.appendChild(def);
    
    for (const name of avatarList) {
      const opt = document.createElement("option"); 
      opt.value = name;
      opt.textContent = name.replace(/\.glb$/i, "").replace(/_/g, " ") + (name.toLowerCase() === "vuong.glb" ? " 🎙️" : "");
      sel.appendChild(opt);
    }
    
    if (selectedName && avatarList.includes(selectedName)) {
      sel.value = selectedName;
    }
  }
}

function setAvatarFromSelect(value) { 
  settings.avatar = value || ""; 
  saveSettings(); 
}

async function reloadAvatar() {
  if (!stage.head) return;
  loading.classList.remove("done"); 
  loading.textContent = "Loading avatar...";
  
  try { 
    await stage.init({ 
      avatarUrl: settings.avatar ? `/avatars/${settings.avatar}` : undefined, 
      onprogress: (ev) => { 
        if (ev.lengthComputable) {
          loading.textContent = `Loading avatar ${Math.min(100, Math.round((ev.loaded / ev.total) * 100))}%`; 
        }
      } 
    }); 
  } catch (err) { 
    console.error(err); 
  }
  
  loading.classList.add("done");
}

// ── Chat / captions ────────────────────────────────────────────────────
function clampRect() {
  const vw = window.innerWidth, vh = window.innerHeight;
  const r = textChat.getBoundingClientRect();
  let l = r.left, t = r.top;
  l = Math.max(10, Math.min(l, vw - r.width - 10)); 
  t = Math.max(10, Math.min(t, vh - r.height - 10));
  textChat.style.left = `${l}px`; 
  textChat.style.top = `${t}px`;
}

function makeDraggable() {
  let dragging = false; 
  let startX, startY, startLeft, startTop;
  
  function getPos(e) { 
    const p = e.changedTouches ? e.changedTouches[0] : e; 
    return { x: p.clientX, y: p.clientY }; 
  }
  
  function onStart(e) { 
    if (e.target.closest("#chat-header-actions") || e.target.closest("#chat-avatar-select")) {
      return; 
    }
    const p = getPos(e); 
    dragging = true; 
    const rect = textChat.getBoundingClientRect(); 
    startX = p.x; 
    startY = p.y; 
    startLeft = rect.left; 
    startTop = rect.top; 
    textChat.classList.add("dragging"); 
    e.preventDefault(); 
  }
  
  function onMove(e) { 
    if (!dragging) return; 
    const p = getPos(e); 
    textChat.style.left = `${startLeft + p.x - startX}px`; 
    textChat.style.top = `${startTop + p.y - startY}px`; 
    textChat.style.right = "auto"; 
    textChat.style.bottom = "auto"; 
    textChat.style.width = ""; 
    textChat.style.height = ""; 
    e.preventDefault(); 
  }
  
  function onEnd() { 
    if (!dragging) return; 
    dragging = false; 
    textChat.classList.remove("dragging"); 
    clampRect(); 
  }
  
  chatHeader.addEventListener("mousedown", onStart); 
  document.addEventListener("mousemove", onMove); 
  document.addEventListener("mouseup", onEnd);
  chatHeader.addEventListener("touchstart", onStart, { passive: false }); 
  document.addEventListener("touchmove", onMove, { passive: false }); 
  document.addEventListener("touchend", onEnd);
}

function makeResizable() {
  let resizing = false; 
  let startX, startY, startW, startH;
  
  function getPos(e) { 
    const p = e.changedTouches ? e.changedTouches[0] : e; 
    return { x: p.clientX, y: p.clientY }; 
  }
  
  function onStart(e) { 
    resizing = true; 
    const rect = textChat.getBoundingClientRect(); 
    const p = getPos(e); 
    startX = p.x; 
    startY = p.y; 
    startW = rect.width; 
    startH = rect.height; 
    textChat.classList.add("resizing"); 
    e.preventDefault(); 
    e.stopPropagation(); 
  }
  
  function onMove(e) { 
    if (!resizing) return; 
    const p = getPos(e); 
    textChat.style.width = `${Math.max(260, startW + p.x - startX)}px`; 
    textChat.style.height = `${Math.max(120, startH + p.y - startY)}px`; 
    textChat.style.right = "auto"; 
    textChat.style.bottom = "auto"; 
    e.preventDefault(); 
  }
  
  function onEnd() { 
    if (!resizing) return; 
    resizing = false; 
    textChat.classList.remove("resizing"); 
  }
  
  chatResizeHandle.addEventListener("mousedown", onStart); 
  document.addEventListener("mousemove", onMove); 
  document.addEventListener("mouseup", onEnd);
  chatResizeHandle.addEventListener("touchstart", onStart, { passive: false }); 
  document.addEventListener("touchmove", onMove, { passive: false }); 
  document.addEventListener("touchend", onEnd);
}

function setCaption(text, kind = "") { 
  caption.textContent = text; 
  caption.className = kind; 
}

function showSubtitles(text) {
  if (!settings.subtitles) return;
  clearTimeout(subtitleTimer);
  subtitles.innerHTML = text;
  subtitles.classList.add("visible");
  
  subtitles.querySelectorAll("a[href]").forEach((a) => {
    a.addEventListener("click", (e) => {
      e.preventDefault();
      const href = a.getAttribute("href");
      if (href) {
        window.open(href, "_blank", "noopener,noreferrer,width=800,height=600,scrollbars=yes");
      }
    });
  });
}

function fadeSubtitles(delayMs = 2600) { 
  clearTimeout(subtitleTimer); 
  subtitleTimer = window.setTimeout(() => subtitles.classList.remove("visible"), delayMs); 
}

function escapeRegex(str) {
  return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
}

function addChatMessage(role, text) {
  const msg = document.createElement("div");
  msg.className = `chat-message ${role}`;
  
  let displayText = text;
  if (role === "assistant" && latestNewsUrl && latestNewsSource) {
    const sourceEscaped = escapeRegex(latestNewsSource);
    const patterns = [
      new RegExp(`\\(nguồn\\s*${sourceEscaped}\\)`, 'gi'),
      new RegExp(`\\(Nguồn\\s*${sourceEscaped}\\)`, 'gi'),
    ];
    
    for (const pattern of patterns) {
      if (pattern.test(displayText)) {
        displayText = displayText.replace(pattern, (match) =>
          `<a href="${latestNewsUrl}" target="_blank" rel="noopener" style="color:#22d3ee;text-decoration:none;">${match}</a>`
        );
        break;
      }
    }
  }
  
  msg.innerHTML = displayText;
  chatMessages.appendChild(msg);
  chatMessages.scrollTop = chatMessages.scrollHeight;
  
  msg.querySelectorAll("a[href]").forEach((a) => {
    a.addEventListener("click", (e) => {
      e.preventDefault();
      const href = a.getAttribute("href");
      if (href) {
        window.open(href, "_blank", "noopener,noreferrer,width=800,height=600,scrollbars=yes");
      }
    });
  });
  
  if (role === "assistant" && preFetchedNews.length > 0) {
    showNewsPanel(preFetchedNews.slice(0, 10));
  }
}

function showTextChat(show) { 
  textChat.hidden = !show; 
  if (show) chatInput.focus(); 
}

function sendTextViaSession(text) {
  if (!client) return false;
  const st = client._status;
  if (st !== "connected" && st !== "ai-speaking" && st !== "processing" && st !== "user-speaking") {
    return false;
  }
  setCaption("SENDING…"); 
  client.sendUserText(text); 
  client.requestResponse(); 
  return true;
}

function sendTextMessage() {
  const text = chatInput.value.trim();
  if (!text) return;
  
  addChatMessage("user", text); 
  chatInput.value = "";
  
  if (!client || !sessionInProgress) {
    const url = new URL(location.href); 
    url.searchParams.set("fakemic", "1"); 
    history.replaceState(null, "", url.href);
    void startTextSession(text); 
    return;
  }
  
  if (!sendTextViaSession(text)) {
    setCaption("QUEUED…");
  }
}

// ── Event listeners for news panel ─────────────────────────────────────
if (newsCloseBtn) {
  newsCloseBtn.addEventListener("click", (e) => { 
    e.stopPropagation(); 
    newsPanel.hidden = true; 
    newsToggleFooter?.classList.remove("active");
  });
}

if (newsToggleBtn) {
  newsToggleBtn.addEventListener("click", (e) => { 
    e.stopPropagation(); 
    toggleNewsCollapse(); 
  });
}

if (newsPanel) {
  newsPanel.addEventListener("click", (e) => {
    if (e.target.closest("#news-header") && !e.target.closest("#news-header-actions")) {
      toggleNewsCollapse();
    }
  });
}

if (newsLoadMoreBtn) {
  newsLoadMoreBtn.addEventListener("click", () => {
    loadNewsPage(newsPage + 1);
  });
}

if (newsToggleFooter) {
  newsToggleFooter.addEventListener("click", () => {
    toggleNewsPanel();
  });
}

if (chatCloseBtn) {
  chatCloseBtn.addEventListener("click", (e) => { 
    e.stopPropagation(); 
    textMode = false; 
    showTextChat(false); 
    textModeBtn.classList.remove("active"); 
  });
}

// ── Button logic ────────────────────────────────────────────────────────
let mainAction = "start";

function setMainButton(action, label) { 
  mainAction = action; 
  mainBtnLabel.textContent = label; 
  mainBtn.disabled = action === "busy"; 
  mainBtn.classList.toggle("live", action === "stop"); 
  muteBtn.hidden = action !== "stop"; 
  textModeBtn.hidden = false; 
  newsToggleFooter.hidden = false;
}

const CAPTIONS = {
  idle: "TAP TO TALK", 
  "creating-session": "REQUESTING A SLOT…", 
  queued: "WAITING IN LINE…",
  "your-turn": "YOUR TURN, TAP TO JOIN", 
  connecting: "CONNECTING…", 
  connected: "GO AHEAD, I'M LISTENING",
  "user-speaking": "LISTENING", 
  processing: "THINKING…", 
  "ai-speaking": "SPEAKING",
  closed: "TAP TO TALK", 
  error: "SOMETHING BROKE, TAP TO RETRY",
};

function onStatus(status) {
  stage.setConversationState(status);
  setCaption(CAPTIONS[status] ?? status, status === "error" ? "error" : status === "idle" || status === "closed" ? "" : "live");
  
  switch (status) {
    case "idle": 
    case "closed": 
      setMainButton("start", "Start talking"); 
      break;
    case "error": 
      setMainButton("start", "Retry"); 
      break;
    case "creating-session": 
    case "connecting": 
      setMainButton("busy", "Connecting…"); 
      break;
    case "queued": 
      setMainButton("stop", "Leave queue"); 
      break;
    case "your-turn": 
      setMainButton("join", "Join now"); 
      break;
    default: 
      setMainButton("stop", "End conversation"); 
      break;
  }
  
  if (status === "user-speaking") { 
    subtitles.classList.remove("visible"); 
    showTextChat(textMode); 
  }
}

// ── Tool runner ─────────────────────────────────────────────────────────
function runTool(name, argsJson, callId) {
  if (!client) return;
  
  let args = {};
  try { 
    args = JSON.parse(argsJson || "{}"); 
  } catch {}
  
  if (name === "get_current_datetime") {
    const now = new Date();
    const { dateStr, timeStr } = formatDateTimeVN(now);
    client.sendToolOutput(callId, `Hôm nay là ${dateStr}. Bây giờ là ${timeStr}.`);
    client.requestResponse(); 
    return;
  }
  
  if (name === "search_wikipedia") {
    const query = args.query || "";
    if (!query) { 
      client.sendToolOutput(callId, `No query.`); 
      client.requestResponse(); 
      return; 
    }
    
    fetch(`/api/wiki/summary?title=${encodeURIComponent(query.replace(/\s+/g, "_"))}`)
      .then(r => r.json())
      .then(data => {
        if (data.extract) { 
          client.sendToolOutput(callId, `From Wikipedia (${data.title}): ${data.extract}\nSource: ${data.url}`); 
          client.requestResponse(); 
          return; 
        }
        fetch(`/api/wiki/search?q=${encodeURIComponent(query)}`)
          .then(r => r.json())
          .then(sd => {
            if (!sd.results?.length) { 
              client.sendToolOutput(callId, `No Wikipedia results for "${query}".`); 
              client.requestResponse(); 
              return; 
            }
            fetch(`/api/wiki/summary?title=${encodeURIComponent(sd.results[0].title)}`)
              .then(r => r.json())
              .then(sum => { 
                client.sendToolOutput(callId, sum.extract ? `From Wikipedia (${sum.title}): ${sum.extract}\nSource: ${sum.url}` : `Wikipedia: ${sd.results.slice(0,3).map(r => `${r.title}: ${r.snippet}`).join("\n")}`); 
                client.requestResponse(); 
              });
          });
      })
      .catch(() => { 
        client.sendToolOutput(callId, `Wikipedia search failed.`); 
        client.requestResponse(); 
      }); 
    return;
  }
  
  if (name === "search_web") {
    const query = args.query || "";
    if (!query) { 
      client.sendToolOutput(callId, `No query.`); 
      client.requestResponse(); 
      return; 
    }
    
    fetch(`/api/web/search?q=${encodeURIComponent(query)}`)
      .then(r => r.json())
      .then(data => {
        if (!data.results?.length) { 
          client.sendToolOutput(callId, `No web results for "${query}".`); 
          client.requestResponse(); 
          return; 
        }
        client.sendToolOutput(callId, `Web results for "${query}":\n${data.results.slice(0,3).map((r,i) => `${i+1}. ${r.title}\n   ${r.snippet}`).join("\n")}`);
        client.requestResponse();
      })
      .catch(() => { 
        client.sendToolOutput(callId, `Web search failed.`); 
        client.requestResponse(); 
      }); 
    return;
  }
  
  const result = stage.runTool(name, args) ?? `Unknown tool: ${name}`;
  client.sendToolOutput(callId, result); 
  client.requestResponse();
}

async function connectSession(c) {
  try { 
    await c.connect(); 
    return c;
  } catch (err) {
    const code = err?.code;
    if (code === "limit") {
      setCaption("DAILY LIMIT REACHED, TRY AGAIN TOMORROW", "error");
    } else if (code === "queue-full") {
      setCaption("ALL SEATS TAKEN, TRY AGAIN", "error");
    } else if (code === "join-expired") {
      setCaption("SPOT EXPIRED, TAP TO RETRY", "error");
    } else if (code !== "aborted") { 
      console.error(err); 
      setCaption("COULD NOT CONNECT, TAP TO RETRY", "error"); 
    }
    await endSession(true); 
    return null;
  }
}

async function startVoiceSession() {
  if (sessionInProgress) return;
  sessionInProgress = true;
  
  await stage.resume();
  
  let micStream;
  if (new URLSearchParams(location.search).has("fakemic")) { 
    const ctx = stage.audioCtx; 
    micStream = ctx.createMediaStreamDestination().stream; 
  } else { 
    try { 
      micStream = await navigator.mediaDevices.getUserMedia({ 
        audio: { 
          echoCancellation: true, 
          noiseSuppression: true, 
          autoGainControl: true 
        } 
      }); 
    } catch { 
      setCaption("MIC BLOCKED", "error"); 
      sessionInProgress = false; 
      return; 
    } 
  }
  
  const audioCtx = stage.audioCtx; 
  const voiceSink = stage.voiceSink;
  if (!audioCtx || !voiceSink) { 
    sessionInProgress = false; 
    return; 
  }
  
  const newsItems = preFetchedNews.length > 0 ? preFetchedNews : (await getHotNews());
  if (!preFetchedNews.length) {
    preFetchedNews = newsItems;
  }
  
  if (newsItems.length > 0) {
    latestNewsUrl = newsItems[0].link;
    try { 
      latestNewsSource = getSourceName(new URL(newsItems[0].link).hostname); 
    } catch { 
      latestNewsSource = "VnExpress"; 
    }
  }
  
  const c = new S2sWsRealtimeClient({
    ...(config.lb ? { sessionUrl: "api/session" } : { directUrl: settings.directUrl }),
    voice: settings.voice, 
    instructions: effectiveInstructions(newsItems),
    micStream, 
    audioContext: audioCtx, 
    outputNode: voiceSink,
    workletBaseUrl: "/worklets/", 
    tools: TOOL_DEFS, 
    _textOnly: false,
  });
  
  client = c; 
  _attachClientEvents(c);
  setCaption("REQUESTING A SLOT…");
  
  const ok = await connectSession(c);
  if (!ok) return;
  
  if (!autoGreetingSent) { 
    c.requestResponse(); 
  }
}

async function startTextSession(initialText) {
  if (sessionInProgress) { 
    if (client && initialText) { 
      client.sendUserText(initialText); 
      client.requestResponse(); 
    } 
    return; 
  }
  
  sessionInProgress = true;
  await stage.resume();
  
  const audioCtx = stage.audioCtx; 
  const voiceSink = stage.voiceSink;
  if (!audioCtx || !voiceSink) { 
    sessionInProgress = false; 
    return; 
  }
  
  const newsItems = preFetchedNews.length > 0 ? preFetchedNews : (await getHotNews());
  if (!preFetchedNews.length) {
    preFetchedNews = newsItems;
  }
  
  if (newsItems.length > 0) {
    latestNewsUrl = newsItems[0].link;
    try { 
      latestNewsSource = getSourceName(new URL(newsItems[0].link).hostname); 
    } catch { 
      latestNewsSource = "VnExpress"; 
    }
  }
  
  const c = new S2sWsRealtimeClient({
    ...(config.lb ? { sessionUrl: "api/session" } : { directUrl: settings.directUrl }),
    voice: settings.voice, 
    instructions: effectiveInstructions(newsItems),
    audioContext: audioCtx, 
    outputNode: voiceSink,
    workletBaseUrl: "/worklets/", 
    tools: TOOL_DEFS, 
    _textOnly: true,
  });
  
  client = c; 
  _attachClientEvents(c);
  textMode = true; 
  showTextChat(true); 
  textModeBtn.classList.add("active");
  
  const ok = await connectSession(c);
  if (!ok) return;
  
  if (!autoGreetingSent) { 
    c.requestResponse(); 
  }
  
  if (initialText) { 
    c.sendUserText(initialText); 
    c.requestResponse(); 
  }
}

function _attachClientEvents(c) {
  c.addEventListener("status", (e) => {
    onStatus(e.detail.status);
  });
  
  c.addEventListener("queue", (e) => {
    const { position } = e.detail;
    setCaption(position > 0 ? `#${position} IN LINE…` : "ALMOST THERE…", "live");
  });
  
  c.addEventListener("transcript", (e) => {
    const { role, text } = e.detail;
    if (role === "assistant" && text) { 
      const normalized = smartNormalize(text); 
      showSubtitles(normalized); 
      addChatMessage("assistant", normalized); 
    }
  });
  
  c.addEventListener("response-finished", () => { 
    autoGreetingSent = true; 
    fadeSubtitles(); 
    if (preFetchedNews.length > 0 && !newsPanel.hidden) {
    }
  });
  
  c.addEventListener("toolcall", (e) => {
    const { name, arguments: args, callId } = e.detail;
    runTool(name, args, callId);
  });
  
  c.addEventListener("server-error", (e) => {
    console.warn("server error:", e.detail.error);
  });
  
  c.addEventListener("error", () => { 
    void endSession(); 
  });
}

async function endSession(silent = false) {
  const c = client; 
  client = null; 
  sessionInProgress = false; 
  autoGreetingSent = false;
  
  if (c) { 
    if (c.options.micStream) {
      for (const track of c.options.micStream?.getTracks() ?? []) {
        track.stop();
      }
    }
    await c.close().catch(() => {}); 
  }
  
  stage.setConversationState("idle"); 
  subtitles.classList.remove("visible");
  
  if (!silent) {
    setCaption(CAPTIONS.idle); 
    setMainButton("start", "Start talking");
  }
}

// ── UI events ───────────────────────────────────────────────────────────
mainBtn.addEventListener("click", () => {
  if (mainAction === "start") {
    if (sessionInProgress) return;
    if (new URLSearchParams(location.search).has("fakemic")) {
      void startTextSession();
    } else {
      void startVoiceSession();
    }
  } else if (mainAction === "join") { 
    stage.resume(); 
    client?.join(); 
  } else if (mainAction === "stop") {
    void endSession();
  }
});

muteBtn.addEventListener("click", () => { 
  muted = !muted; 
  client?.setMuted(muted); 
  muteBtn.classList.toggle("active", muted); 
  muteBtn.setAttribute("aria-label", muted ? "Unmute microphone" : "Mute microphone"); 
});

textModeBtn.addEventListener("click", () => { 
  textMode = !textMode; 
  showTextChat(textMode); 
  textModeBtn.classList.toggle("active", textMode); 
});

chatSendBtn.addEventListener("click", () => sendTextMessage());

chatInput.addEventListener("keypress", (e) => { 
  if (e.key === "Enter") {
    sendTextMessage();
  }
});

chatAvatarSelect.addEventListener("change", () => { 
  setAvatarFromSelect(chatAvatarSelect.value); 
  void reloadAvatar(); 
});

settingsAvatarSelect.addEventListener("change", () => { 
  setAvatarFromSelect(settingsAvatarSelect.value); 
  chatAvatarSelect.value = settingsAvatarSelect.value; 
  void reloadAvatar(); 
});

settingsBtn.addEventListener("click", () => { 
  inputVoice.value = settings.voice; 
  inputInstructions.value = settings.instructions; 
  inputDirectUrl.value = settings.directUrl; 
  inputSubtitles.checked = settings.subtitles; 
  settingsAvatarSelect.value = chatAvatarSelect.value; 
  settingsDialog.showModal(); 
});

settingsDialog.addEventListener("close", () => {
  settings = { 
    voice: inputVoice.value || DEFAULT_VOICE, 
    avatar: settingsAvatarSelect.value || "", 
    instructions: inputInstructions.value, 
    directUrl: inputDirectUrl.value.trim(), 
    subtitles: inputSubtitles.checked 
  };
  
  if (settings.avatar !== "vuong.glb") {
    autoGreetingSent = false;
  }
  
  saveSettings(); 
  chatAvatarSelect.value = settings.avatar; 
  
  if (!settings.subtitles) {
    subtitles.classList.remove("visible");
  }
  
  client?.updateSession({ 
    voice: settings.voice, 
    instructions: effectiveInstructions(preFetchedNews) 
  });
});

window.addEventListener("beforeunload", () => { 
  client?.close(); 
});

// ── Boot ────────────────────────────────────────────────────────────────
async function boot() {
  for (const v of VOICES) { 
    const o = document.createElement("option"); 
    o.value = v; 
    o.textContent = v.replaceAll("_", " "); 
    inputVoice.append(o); 
  }
  
  try { 
    const resp = await fetch("api/config"); 
    if (resp.ok) {
      config = { ...config, ...(await resp.json()) };
    }
  } catch {}
  
  directUrlRow.hidden = !config.allowDirect;
  
  await fetchAvatarList(); 
  populateAvatarSelects(settings.avatar);
  makeDraggable(); 
  makeResizable();
  
  const url = new URL(location.href); 
  url.searchParams.set("fakemic", "1"); 
  history.replaceState(null, "", url.href);
  
  setCaption("WAKING HER UP…"); 
  setMainButton("busy", "Loading…");
  
  const newsPromise = (settings.avatar === "vuong.glb" || !settings.avatar) ? getHotNews(1).catch(() => []) : Promise.resolve([]);
  
  try { 
    await stage.init({ 
      avatarUrl: settings.avatar ? `/avatars/${settings.avatar}` : undefined, 
      onprogress: (ev) => { 
        if (ev.lengthComputable) {
          loading.textContent = `Loading avatar ${Math.min(100, Math.round((ev.loaded / ev.total) * 100))}%`; 
        }
      } 
    }); 
  } catch (err) { 
    console.error(err); 
    loading.textContent = "Avatar failed to load. Reload."; 
    setCaption("AVATAR FAILED", "error"); 
    return; 
  }
  
  preFetchedNews = await newsPromise;
  loading.classList.add("done");
  setCaption(CAPTIONS.idle); 
  setMainButton("start", "Start talking");
  
  if (newsToggleFooter) {
    newsToggleFooter.hidden = false;
  }
}

void boot();