const $ = (id) => document.getElementById(id);
const state = {
  sessionId: localStorage.getItem("lazyboy.session") || "",
  sessions: [],
  running: false,
  source: null,
};

function tokenHeaders() {
  const token = localStorage.getItem("lazyboy.token") || "";
  return token ? { Authorization: `Bearer ${token}` } : {};
}

async function api(path, opts = {}) {
  const res = await fetch(path, {
    ...opts,
    headers: {
      "content-type": "application/json",
      ...tokenHeaders(),
      ...(opts.headers || {}),
    },
  });
  const raw = await res.text();
  let data = null;
  try {
    data = raw ? JSON.parse(raw) : null;
  } catch {
    data = null;
  }
  if (!res.ok) {
    throw new Error((data && data.error) || raw || String(res.status));
  }
  return data;
}

function setStatus(text) {
  $("header-status").textContent = text;
}

function renderSessions() {
  const list = $("session-list");
  list.innerHTML = "";
  for (const s of state.sessions) {
    const btn = document.createElement("button");
    btn.className = "session-item" + (s.id === state.sessionId ? " active" : "");
    btn.innerHTML = `<strong>${s.running ? "進行中" : "對話"}</strong><small>${escapeHtml(s.preview || s.id)}</small>`;
    btn.onclick = () => openSession(s.id);
    list.appendChild(btn);
  }
}

function escapeHtml(s) {
  return String(s)
    .replace(/&/g, "&amp;")
    .replace(/</g, "&lt;")
    .replace(/>/g, "&gt;");
}

function addBubble(role, content) {
  const row = document.createElement("div");
  row.className = `row ${role}`;
  row.innerHTML = `<div class="bubble">${escapeHtml(content)}</div>`;
  $("transcript").appendChild(row);
  $("transcript").scrollTop = $("transcript").scrollHeight;
}

function addActivity(text) {
  const el = document.createElement("div");
  el.className = "activity";
  el.textContent = text;
  $("transcript").appendChild(el);
  $("transcript").scrollTop = $("transcript").scrollHeight;
}

function showTyping(on) {
  $("transcript").querySelector(".typing")?.remove();
  if (!on) return;
  const el = document.createElement("div");
  el.className = "typing";
  el.innerHTML = "<i></i><i></i><i></i>";
  $("transcript").appendChild(el);
  $("transcript").scrollTop = $("transcript").scrollHeight;
}

function renderQuestion(q) {
  const card = $("question-card");
  if (!q) {
    card.classList.add("hidden");
    card.innerHTML = "";
    return;
  }
  const prompt = q.question || q.reason || "需要你的回覆";
  const options = (q.options || []).map((o) => (typeof o === "string" ? o : o.label || o.value)).filter(Boolean);
  card.classList.remove("hidden");
  card.innerHTML = `<p>${escapeHtml(prompt)}</p>` + (options.length
    ? `<div class="options">${options.map((o) => `<button type="button" data-answer="${escapeHtml(o)}">${escapeHtml(o)}</button>`).join("")}</div>`
    : "");
  card.querySelectorAll("button").forEach((b) => {
    b.onclick = () => send(b.dataset.answer);
  });
}

function renderPlan(plan) {
  if (!plan || !plan.length) return;
  const el = document.createElement("div");
  el.className = "plan";
  el.innerHTML = "<strong>計畫</strong><ol>" + plan.map((step) => {
    const text = step.step || step;
    const status = step.status || "";
    return `<li class="${status}">${escapeHtml(text)}</li>`;
  }).join("") + "</ol>";
  $("transcript").appendChild(el);
}

async function loadSessions() {
  const data = await api("/api/sessions");
  state.sessions = data.sessions || [];
  renderSessions();
}

async function openSession(id) {
  state.sessionId = id;
  localStorage.setItem("lazyboy.session", id);
  renderSessions();
  closeSidebar();
  const data = await api(`/api/sessions/${id}`);
  $("transcript").innerHTML = "";
  for (const item of data.transcript || []) addBubble(item.role, item.content);
  renderPlan(data.plan);
  renderQuestion(data.pending_question);
  state.running = !!data.running;
  $("stop-btn").classList.toggle("hidden", !state.running);
  showTyping(state.running);
  setStatus(state.running ? "工作中" : data.last_verdict || "準備好了");
  listen(id);
}

function listen(id) {
  state.source?.close();
  clearInterval(state.poll);
  const src = new EventSource(`/api/sessions/${id}/events`);
  state.source = src;
  src.onmessage = (ev) => {
    let data;
    try { data = JSON.parse(ev.data); } catch { return; }
    handleEvent(data);
  };
  state.poll = setInterval(async () => {
    if (!state.running) return;
    try {
      const data = await api(`/api/sessions/${id}`);
      if (data.running !== state.running && !data.running) {
        handleEvent({
          type: "turn_ended",
          verdict: data.last_verdict,
          pending_question: data.pending_question,
          plan: data.plan,
        });
      }
    } catch {
      /* keep polling */
    }
  }, 2000);
}

function handleEvent(data) {
  switch (data.type) {
    case "user":
      addBubble("user", data.content);
      break;
    case "message":
      showTyping(false);
      addBubble("assistant", data.content);
      break;
    case "status":
    case "progress":
      addActivity(data.message);
      break;
    case "tool_started":
      addActivity(`〔開始〕${data.name}`);
      showTyping(true);
      break;
    case "tool_finished":
      addActivity(`〔${data.success ? "完成" : "失敗"}〕${data.name}`);
      break;
    case "waiting":
      setStatus(data.stage || "等待中");
      break;
    case "question":
      renderQuestion(data.question);
      showTyping(false);
      break;
    case "plan_updated":
      renderPlan(data.plan);
      break;
    case "turn_ended":
      state.running = false;
      $("stop-btn").classList.add("hidden");
      showTyping(false);
      renderQuestion(data.pending_question);
      setStatus(data.verdict || "完成");
      loadSessions();
      break;
    default:
      break;
  }
}

async function send(text) {
  const value = (text ?? $("prompt").value).trim();
  if (!value) return;
  if (!state.sessionId) {
    const created = await api("/api/sessions", { method: "POST", body: "{}" });
    state.sessionId = created.id;
    localStorage.setItem("lazyboy.session", created.id);
    await loadSessions();
    listen(created.id);
  }
  $("prompt").value = "";
  resizePrompt();
  $("send-btn").disabled = true;
  addBubble("user", value);
  renderQuestion(null);
  state.running = true;
  $("stop-btn").classList.remove("hidden");
  showTyping(true);
  setStatus("工作中");
  try {
    await api(`/api/sessions/${state.sessionId}/messages`, {
      method: "POST",
      body: JSON.stringify({ text: value }),
    });
  } catch (err) {
    state.running = false;
    $("stop-btn").classList.add("hidden");
    showTyping(false);
    setStatus(String(err.message || err));
    addActivity("送出失敗：" + (err.message || err));
  }
}

async function newChat() {
  const created = await api("/api/sessions", { method: "POST", body: "{}" });
  await loadSessions();
  await openSession(created.id);
}

function resizePrompt() {
  const el = $("prompt");
  el.style.height = "auto";
  el.style.height = Math.min(el.scrollHeight, window.innerHeight * 0.3) + "px";
  $("send-btn").disabled = !el.value.trim();
}

function openSidebar() {
  $("sidebar").classList.add("open");
  $("sidebar-backdrop").classList.remove("hidden");
}
function closeSidebar() {
  $("sidebar").classList.remove("open");
  $("sidebar-backdrop").classList.add("hidden");
}

async function openComputer() {
  $("computer-pane").hidden = false;
  $("tab-computer").classList.add("active");
  $("tab-chat").classList.remove("active");
  $("computer-status").textContent = "正在啟動我的電腦…";
  try {
    const data = await api("/api/computer", { method: "POST", body: "{}" });
    $("computer-frame").src = data.viewer_url;
    $("computer-status").textContent = data.ready ? "已連線同一台 Docker 桌面" : (data.error || "桌面啟動中");
  } catch (err) {
    $("computer-status").textContent = String(err.message || err);
  }
}
function closeComputer() {
  $("computer-pane").hidden = true;
  $("tab-chat").classList.add("active");
  $("tab-computer").classList.remove("active");
}

$("composer").addEventListener("submit", (e) => {
  e.preventDefault();
  send();
});
$("prompt").addEventListener("input", resizePrompt);
$("prompt").addEventListener("keydown", (e) => {
  if (e.key === "Enter" && !e.shiftKey && window.matchMedia("(min-width: 861px)").matches) {
    e.preventDefault();
    send();
  }
});
$("new-chat").onclick = () => newChat();
$("menu-btn").onclick = openSidebar;
$("sidebar-backdrop").onclick = closeSidebar;
$("computer-btn").onclick = openComputer;
$("computer-close").onclick = closeComputer;
$("tab-chat").onclick = () => {
  closeComputer();
  closeSidebar();
};
$("tab-computer").onclick = openComputer;
$("stop-btn").onclick = async () => {
  if (state.sessionId) await api(`/api/sessions/${state.sessionId}/stop`, { method: "POST", body: "{}" });
};

if ("serviceWorker" in navigator) {
  navigator.serviceWorker.register("/sw.js").catch(() => {});
}

(async () => {
  try {
    const health = await api("/api/health");
    $("model-label").textContent = health.model || "grok-4.6";
    await loadSessions();
    if (state.sessionId) await openSession(state.sessionId);
    else if (state.sessions[0]) await openSession(state.sessions[0].id);
  } catch (err) {
    setStatus("無法連線：" + err.message);
  }
})();