import * as THREE from "three";
import { OrbitControls } from "three/addons/controls/OrbitControls.js";
import { GLTFLoader } from "three/addons/loaders/GLTFLoader.js";
import { VRMLoaderPlugin, VRMUtils } from "@pixiv/three-vrm";

const statusEl = document.getElementById("status");
const outputEl = document.getElementById("output");
const healthBtn = document.getElementById("healthBtn");
const offerBtn = document.getElementById("offerBtn");
const resetBtn = document.getElementById("resetBtn");
const sendBtn = document.getElementById("sendBtn");
const chatInput = document.getElementById("chatInput");
const remoteAudio = document.getElementById("remoteAudio");
const modelFile = document.getElementById("modelFile");
const modelUrl = document.getElementById("modelUrl");
const loadModelBtn = document.getElementById("loadModelBtn");
const resetViewBtn = document.getElementById("resetViewBtn");
const avatarCanvas = document.getElementById("avatarCanvas");
const modelStatus = document.getElementById("modelStatus");
const modelName = document.getElementById("modelName");
const animationBuffer = document.getElementById("animationBuffer");

remoteAudio.muted = false;
remoteAudio.volume = 1.0;

const messagesEl = document.getElementById("messages");
const connBadge = document.getElementById("connBadge");
const animationConn = document.getElementById("animationConn");
const animationDriver = document.getElementById("animationDriver");
const animationFrames = document.getElementById("animationFrames");
const animationPreview = document.getElementById("animationPreview");
const mPeers = document.getElementById("mPeers");
const mBusy = document.getElementById("mBusy");
const mLatency = document.getElementById("mLatency");
const mAsrLatency = document.getElementById("mAsrLatency");
const mLlmLatency = document.getElementById("mLlmLatency");
const mLlmSource = document.getElementById("mLlmSource");
const mLlmHistory = document.getElementById("mLlmHistory");
const mTtsLatency = document.getElementById("mTtsLatency");
const mTtsFirst = document.getElementById("mTtsFirst");
const mTts = document.getElementById("mTts");
const mBargeIn = document.getElementById("mBargeIn");
const mInputMode = document.getElementById("mInputMode");
const mVadCount = document.getElementById("mVadCount");
const mAnimClients = document.getElementById("mAnimClients");
const mAnimDriver = document.getElementById("mAnimDriver");
const mAnimFrames = document.getElementById("mAnimFrames");
const dConn = document.getElementById("dConn");
const dVad = document.getElementById("dVad");
const dAsr = document.getElementById("dAsr");
const dLlm = document.getElementById("dLlm");
const dTts = document.getElementById("dTts");

let pc = null;
let evt = null;
let subtitleWs = null;
let animationWs = null;
let localMicStream = null;
let aiStreamingEl = null;

const AUTO_RECONNECT_KEY = "visual_chat_auto_reconnect";
const ANIMATION_BUFFER_MS = 120;
const DEFAULT_BODY_MODEL_URL = "https://cdn.jsdelivr.net/gh/pixiv/three-vrm@release/packages/three-vrm/examples/models/VRM1_Constraint_Twist_Sample.vrm";
const DEFAULT_VRM_FALLBACK_URL = "https://raw.githubusercontent.com/pixiv/three-vrm/dev/packages/three-vrm/examples/models/VRM1_Constraint_Twist_Sample.vrm";
const CLOCK = new THREE.Clock();

const stateMap = {
  "SessionState.IDLE": "空闲",
  "SessionState.USER_SPEAKING": "用户说话",
  "SessionState.THINKING": "思考中",
  "SessionState.AVATAR_SPEAKING": "数字人说话",
  idle: "空闲",
  user_speaking: "用户说话",
  thinking: "思考中",
  avatar_speaking: "数字人说话",
};

const renderer = new THREE.WebGLRenderer({ canvas: avatarCanvas, antialias: true, alpha: true });
renderer.setPixelRatio(Math.min(window.devicePixelRatio, 2));
renderer.outputColorSpace = THREE.SRGBColorSpace;

const scene = new THREE.Scene();
scene.fog = new THREE.Fog(0x0a1017, 5.5, 11.5);

const camera = new THREE.PerspectiveCamera(30, 16 / 9, 0.1, 100);
camera.position.set(0, 1.45, 2.65);

const controls = new OrbitControls(camera, avatarCanvas);
controls.target.set(0, 1.15, 0);
controls.enableDamping = true;
controls.minDistance = 1.3;
controls.maxDistance = 4.5;
controls.maxPolarAngle = Math.PI * 0.58;
controls.minPolarAngle = Math.PI * 0.22;

const avatarState = {
  currentRoot: null,
  currentVrm: null,
  morphBindings: new Map(),
  pendingFrames: [],
  scheduleCursorMs: performance.now(),
  lastAppliedSeq: -1,
  activeControls: {
    jawOpen: 0,
    viseme_aa: 0,
    viseme_ee: 0,
    viseme_oh: 0,
    mouthPucker: 0,
    headYaw: 0,
    headPitch: 0,
    headRoll: 0,
  },
  headBone: null,
  neckBone: null,
  idleRig: null,
  debugRig: null,
  debugJaw: null,
  debugMouth: null,
};

const gltfLoader = new GLTFLoader();
gltfLoader.register((parser) => new VRMLoaderPlugin(parser));
gltfLoader.crossOrigin = "anonymous";

const TMP_EULER = new THREE.Euler();
const TMP_QUATERNION = new THREE.Quaternion();

function fmtTime() {
  return new Date().toLocaleTimeString("zh-CN", { hour12: false });
}

function toCnState(raw) {
  return stateMap[raw] || raw;
}

function addMessage(role, text) {
  const row = document.createElement("div");
  row.className = "msg-row";
  const div = document.createElement("div");
  div.className = `msg ${role}`;
  div.textContent = text;
  const time = document.createElement("div");
  time.className = `msg-time ${role}`;
  time.textContent = fmtTime();
  row.appendChild(div);
  row.appendChild(time);
  messagesEl.appendChild(row);
  messagesEl.scrollTop = messagesEl.scrollHeight;
  return div;
}

function setConnBadge(label, kind = "neutral") {
  connBadge.textContent = label;
  connBadge.className = `badge ${kind}`;
}

function setDot(el, kind) {
  el.className = `dot ${kind}`;
}

function initStage() {
  scene.background = new THREE.Color(0x0b1118);

  const hemiLight = new THREE.HemisphereLight(0xb8d7ff, 0x142334, 1.65);
  hemiLight.position.set(0, 2.6, 0);
  scene.add(hemiLight);

  const keyLight = new THREE.DirectionalLight(0xffffff, 1.7);
  keyLight.position.set(1.4, 2.2, 2.0);
  scene.add(keyLight);

  const rimLight = new THREE.DirectionalLight(0x67c9ff, 0.8);
  rimLight.position.set(-2.0, 1.4, -1.5);
  scene.add(rimLight);

  const floor = new THREE.Mesh(
    new THREE.CircleGeometry(2.8, 48),
    new THREE.MeshStandardMaterial({
      color: 0x101b28,
      roughness: 0.94,
      metalness: 0.08,
      transparent: true,
      opacity: 0.9,
    }),
  );
  floor.rotation.x = -Math.PI / 2;
  floor.position.y = -0.02;
  scene.add(floor);

  const halo = new THREE.Mesh(
    new THREE.RingGeometry(1.2, 1.95, 64),
    new THREE.MeshBasicMaterial({ color: 0x153a62, transparent: true, opacity: 0.28, side: THREE.DoubleSide }),
  );
  halo.rotation.x = -Math.PI / 2;
  halo.position.y = 0.01;
  scene.add(halo);

  createDebugRig();
  resizeStage();
  renderLoop();
}

function createDebugRig() {
  const group = new THREE.Group();

  const bustMaterial = new THREE.MeshStandardMaterial({
    color: 0xc7d2e0,
    roughness: 0.72,
    metalness: 0.05,
  });
  const accentMaterial = new THREE.MeshStandardMaterial({
    color: 0x0f172a,
    roughness: 0.35,
    metalness: 0.18,
  });
  const lipMaterial = new THREE.MeshStandardMaterial({
    color: 0x8b425f,
    roughness: 0.56,
    metalness: 0.02,
  });

  const torso = new THREE.Mesh(new THREE.CapsuleGeometry(0.34, 0.72, 8, 14), bustMaterial);
  torso.position.set(0, 0.42, 0);
  group.add(torso);

  const neck = new THREE.Group();
  neck.position.set(0, 0.95, 0);
  group.add(neck);

  const head = new THREE.Mesh(new THREE.SphereGeometry(0.34, 32, 32), bustMaterial);
  head.scale.set(0.92, 1.03, 0.92);
  neck.add(head);

  const hair = new THREE.Mesh(new THREE.SphereGeometry(0.35, 32, 32, 0, Math.PI * 2, 0, Math.PI * 0.58), accentMaterial);
  hair.position.set(0, 0.06, 0);
  neck.add(hair);

  const leftEye = new THREE.Mesh(new THREE.SphereGeometry(0.028, 16, 16), accentMaterial);
  leftEye.position.set(-0.1, 0.03, 0.28);
  neck.add(leftEye);

  const rightEye = new THREE.Mesh(new THREE.SphereGeometry(0.028, 16, 16), accentMaterial);
  rightEye.position.set(0.1, 0.03, 0.28);
  neck.add(rightEye);

  const jawPivot = new THREE.Group();
  jawPivot.position.set(0, -0.06, 0.15);
  neck.add(jawPivot);

  const jaw = new THREE.Mesh(new THREE.BoxGeometry(0.24, 0.08, 0.16), bustMaterial);
  jaw.position.set(0, -0.08, 0.02);
  jawPivot.add(jaw);

  const mouth = new THREE.Mesh(new THREE.BoxGeometry(0.18, 0.025, 0.02), lipMaterial);
  mouth.position.set(0, -0.02, 0.31);
  neck.add(mouth);

  scene.add(group);
  avatarState.currentRoot = group;
  avatarState.debugRig = group;
  avatarState.debugJaw = jawPivot;
  avatarState.debugMouth = mouth;
  avatarState.headBone = neck;
  avatarState.neckBone = neck;
}

function resizeStage() {
  const rect = avatarCanvas.getBoundingClientRect();
  if (!rect.width || !rect.height) return;
  renderer.setSize(rect.width, rect.height, false);
  camera.aspect = rect.width / rect.height;
  camera.updateProjectionMatrix();
}

function renderLoop() {
  requestAnimationFrame(renderLoop);
  const delta = CLOCK.getDelta();
  const elapsed = CLOCK.getElapsedTime();
  controls.update();
  flushAnimationQueue();
  applyProceduralIdlePose(elapsed);
  applyAnimationControls(avatarState.activeControls);
  avatarState.currentVrm?.update?.(delta);
  renderer.render(scene, camera);
}

function updateMetrics(data) {
  mPeers.textContent = String(data.peers ?? 0);
  mBusy.textContent = data.pipeline_busy ? "是" : "否";
  mLatency.textContent = `${data.last_latency_ms ?? 0} ms`;
  mAsrLatency.textContent = `${data.last_asr_latency_ms ?? 0} ms`;
  mLlmLatency.textContent = `${data.last_llm_latency_ms ?? 0} ms`;
  mLlmSource.textContent = data.last_llm_source === "online" ? "在线" : "兜底";
  mLlmHistory.textContent = String(data?.llm?.history_items ?? 0);
  mTtsLatency.textContent = `${data.last_tts_latency_ms ?? 0} ms`;
  mTtsFirst.textContent = `${data.last_tts_first_chunk_ms ?? 0} ms`;
  mTts.textContent = data?.tts?.ready ? "就绪" : "未就绪";
  mBargeIn.textContent = `${data.last_barge_in_ms ?? 0} ms (${data.barge_in_count ?? 0})`;
  mInputMode.textContent = data.last_input_mode === "voice" ? "语音" : data.last_input_mode === "text" ? "文本" : "none";
  mVadCount.textContent = `${data.vad_start_count ?? 0}/${data.vad_end_count ?? 0}`;
  mAnimClients.textContent = String(data.animation_clients ?? 0);
  mAnimDriver.textContent = data?.avatar?.driver || data.last_animation_mode || "--";
  mAnimFrames.textContent = String(data.last_animation_frame_count ?? data?.avatar?.last_frame_count ?? 0);

  setDot(dConn, (data.peers ?? 0) > 0 ? "ok" : "warn");
  setDot(dVad, (data.vad_start_count ?? 0) > 0 ? "ok" : "warn");
  setDot(dAsr, data?.asr?.ready ? "ok" : "warn");
  setDot(dLlm, data?.llm?.ready ? "ok" : "bad");
  setDot(dTts, data?.tts?.ready ? "ok" : "warn");
}

function queueAnimationFrames(payload) {
  const frames = Array.isArray(payload.frames) ? payload.frames : [];
  const now = performance.now();
  const frameWindowMs = (1000 / Math.max(1, payload.fps || 25));

  if (payload.type === "animation_reset" || payload.type === "animation_state") {
    avatarState.pendingFrames = [];
    avatarState.scheduleCursorMs = now + ANIMATION_BUFFER_MS;
    avatarState.activeControls = {
      jawOpen: 0,
      viseme_aa: 0,
      viseme_ee: 0,
      viseme_oh: 0,
      mouthPucker: 0,
      headYaw: 0,
      headPitch: 0,
      headRoll: 0,
    };
  }

  const baseTime = Math.max(now + ANIMATION_BUFFER_MS, avatarState.scheduleCursorMs);
  frames.forEach((frame, index) => {
    const fallbackTime = index * frameWindowMs;
    avatarState.pendingFrames.push({
      dueAt: baseTime + (frame.time_ms ?? fallbackTime),
      seq: frame.seq ?? index,
      controls: frame.controls || {},
    });
  });

  avatarState.pendingFrames.sort((a, b) => a.dueAt - b.dueAt || a.seq - b.seq);
  avatarState.scheduleCursorMs = baseTime + (payload.duration_ms ?? frames.length * frameWindowMs);
  animationBuffer.textContent = String(avatarState.pendingFrames.length);
}

function flushAnimationQueue() {
  const now = performance.now();
  let frameToApply = null;
  while (avatarState.pendingFrames.length > 0 && avatarState.pendingFrames[0].dueAt <= now) {
    frameToApply = avatarState.pendingFrames.shift();
  }

  if (frameToApply && frameToApply.seq !== avatarState.lastAppliedSeq) {
    avatarState.lastAppliedSeq = frameToApply.seq;
    avatarState.activeControls = {
      ...avatarState.activeControls,
      ...frameToApply.controls,
    };
  }

  animationBuffer.textContent = String(avatarState.pendingFrames.length);
}

function applyAnimationControls(controls) {
  const safeControls = controls || {};
  const jawOpen = clampControl(safeControls.jawOpen);
  const visemeAa = clampControl(safeControls.viseme_aa ?? jawOpen);
  const visemeEe = clampControl(safeControls.viseme_ee);
  const visemeOh = clampControl(safeControls.viseme_oh);
  const mouthPucker = clampControl(safeControls.mouthPucker);
  const headYaw = clampSigned(safeControls.headYaw, 0.35);
  const headPitch = clampSigned(safeControls.headPitch, 0.3);
  const headRoll = clampSigned(safeControls.headRoll, 0.24);
  const hasFacialRig = Boolean(avatarState.currentVrm?.expressionManager) || avatarState.morphBindings.size > 0;
  const t = performance.now() * 0.001;

  if (avatarState.currentVrm?.expressionManager) {
    setExpressionValue("aa", visemeAa);
    setExpressionValue("ee", visemeEe);
    setExpressionValue("oh", visemeOh);
    setExpressionValue("ou", Math.max(visemeOh * 0.35, mouthPucker));
  }

  if (avatarState.morphBindings.size > 0) {
    setMorphValue("jawOpen", jawOpen);
    setMorphValue("viseme_aa", visemeAa);
    setMorphValue("viseme_ee", visemeEe);
    setMorphValue("viseme_oh", visemeOh);
    setMorphValue("mouthPucker", mouthPucker);
  }

  // For plain head meshes (no VRM expressions and no morph targets),
  // amplify head motion to keep speaking visually obvious.
  const yawApplied = hasFacialRig ? headYaw * 1.8 : headYaw * 10.0 + Math.sin(t * 5.0) * jawOpen * 0.09;
  const pitchApplied = hasFacialRig ? headPitch * 1.6 : headPitch * 10.0 + jawOpen * 0.12;
  const rollApplied = hasFacialRig ? headRoll * 1.6 : headRoll * 8.0 + Math.sin(t * 4.0) * jawOpen * 0.04;

  applyBoneRotation(avatarState.headBone, pitchApplied, yawApplied, rollApplied);
  if (avatarState.neckBone && avatarState.neckBone !== avatarState.headBone) {
    applyBoneRotation(avatarState.neckBone, pitchApplied * 0.4, yawApplied * 0.5, rollApplied * 0.4);
  }

  if (!hasFacialRig && avatarState.currentRoot && avatarState.currentRoot !== avatarState.debugRig) {
    const baseScale = 1.0 + jawOpen * 0.03;
    avatarState.currentRoot.scale.set(baseScale, baseScale, baseScale);
  }

  if (avatarState.debugJaw) {
    avatarState.debugJaw.rotation.x = jawOpen * 0.5;
    avatarState.debugJaw.position.y = -0.06 - jawOpen * 0.015;
  }
  if (avatarState.debugMouth) {
    avatarState.debugMouth.scale.x = 1.0 + mouthPucker * 0.45;
    avatarState.debugMouth.scale.y = 1.0 + jawOpen * 3.8;
    avatarState.debugMouth.position.z = 0.31 + mouthPucker * 0.01;
  }
}

function setExpressionValue(name, value) {
  try {
    avatarState.currentVrm.expressionManager.setValue(name, value);
  } catch (_) {
    // no-op: expression name may not exist on the current model
  }
}

function setMorphValue(controlName, value) {
  const bindings = avatarState.morphBindings.get(controlName) || [];
  bindings.forEach((binding) => {
    binding.mesh.morphTargetInfluences[binding.index] = value;
  });
}

function clampControl(value) {
  return Math.min(1, Math.max(0, Number(value) || 0));
}

function clampSigned(value, limit) {
  return Math.min(limit, Math.max(-limit, Number(value) || 0));
}

function resetView() {
  camera.position.set(0, 1.45, 2.65);
  controls.target.set(0, 1.15, 0);
  controls.update();
}

function resetAvatarPose() {
  avatarState.activeControls = {
    jawOpen: 0,
    viseme_aa: 0,
    viseme_ee: 0,
    viseme_oh: 0,
    mouthPucker: 0,
    headYaw: 0,
    headPitch: 0,
    headRoll: 0,
  };
  applyAnimationControls(avatarState.activeControls);
}

function detachCurrentAvatar() {
  if (avatarState.currentRoot && avatarState.currentRoot !== avatarState.debugRig) {
    scene.remove(avatarState.currentRoot);
  }
  avatarState.pendingFrames = [];
  avatarState.scheduleCursorMs = performance.now() + ANIMATION_BUFFER_MS;
  avatarState.lastAppliedSeq = -1;
  avatarState.idleRig = null;
  avatarState.currentRoot = avatarState.debugRig;
  avatarState.currentVrm = null;
  avatarState.morphBindings.clear();
  avatarState.headBone = avatarState.debugRig.children[1];
  avatarState.neckBone = avatarState.debugRig.children[1];
  avatarState.debugRig.visible = true;
  modelName.textContent = "debug-avatar";
}

async function loadModelFromUrl(url) {
  if (!url) return false;
  modelStatus.textContent = "模型加载中...";
  try {
    const gltf = await gltfLoader.loadAsync(url);
    attachLoadedAsset(gltf, url.split("/").pop() || url);
    modelStatus.textContent = "模型已加载";
    return true;
  } catch (error) {
    console.error(error);
    modelStatus.textContent = "模型加载失败，已回退调试头像";
    addMessage("system", `模型加载失败：${error?.message || error}`);
    detachCurrentAvatar();
    return false;
  }
}

async function loadDefaultAvatarModel() {
  modelUrl.value = DEFAULT_BODY_MODEL_URL;
  const ok = await loadModelFromUrl(DEFAULT_BODY_MODEL_URL);
  if (!ok) {
    modelUrl.value = DEFAULT_VRM_FALLBACK_URL;
    await loadModelFromUrl(DEFAULT_VRM_FALLBACK_URL);
  }
}

async function loadModelFromFile(file) {
  if (!file) return;
  const url = URL.createObjectURL(file);
  modelStatus.textContent = "本地模型加载中...";
  try {
    const gltf = await gltfLoader.loadAsync(url);
    attachLoadedAsset(gltf, file.name);
    modelStatus.textContent = "本地模型已加载";
  } catch (error) {
    console.error(error);
    modelStatus.textContent = "本地模型加载失败，已回退调试头像";
    addMessage("system", `本地模型加载失败：${error?.message || error}`);
    detachCurrentAvatar();
  } finally {
    URL.revokeObjectURL(url);
  }
}

function attachLoadedAsset(gltf, label) {
  detachCurrentAvatar();

  const vrm = gltf.userData?.vrm || null;
  const root = vrm?.scene || gltf.scene;
  if (!root) {
    throw new Error("模型中未找到可渲染的 scene");
  }

  if (vrm) {
    VRMUtils.removeUnnecessaryVertices(gltf.scene);
    VRMUtils.combineSkeletons(gltf.scene);
    VRMUtils.combineMorphs(vrm);
    VRMUtils.rotateVRM0(vrm);
  }

  root.traverse((obj) => {
    obj.frustumCulled = false;
  });

  root.position.set(0, 0, 0);
  root.rotation.set(0, 0, 0);
  root.scale.setScalar(1);
  scene.add(root);

  avatarState.currentRoot = root;
  avatarState.currentVrm = vrm;
  avatarState.debugRig.visible = false;
  avatarState.morphBindings = collectMorphBindings(root);
  avatarState.headBone = resolveHeadBone(vrm, root) || avatarState.debugRig.children[1];
  avatarState.neckBone = resolveNeckBone(vrm, root) || avatarState.headBone;
  avatarState.idleRig = buildIdleRig(vrm, root);
  avatarState.pendingFrames = [];
  avatarState.scheduleCursorMs = performance.now() + ANIMATION_BUFFER_MS;
  avatarState.lastAppliedSeq = -1;

  fitCameraToObject(root);
  resetAvatarPose();
  modelName.textContent = label;
}

function fitCameraToObject(root) {
  const box = new THREE.Box3().setFromObject(root);
  const center = new THREE.Vector3();
  const size = new THREE.Vector3();
  box.getCenter(center);
  box.getSize(size);

  const radius = Math.max(size.x, size.y, size.z, 1.2);
  controls.target.copy(center).add(new THREE.Vector3(0, size.y * 0.1, 0));
  camera.position.set(center.x, center.y + size.y * 0.1, center.z + radius * 1.9);
  controls.update();
}

function resolveHeadBone(vrm, root) {
  return (
    vrm?.humanoid?.getNormalizedBoneNode?.("head") ||
    vrm?.humanoid?.getRawBoneNode?.("head") ||
    root.getObjectByName("Head") ||
    root.getObjectByName("head") ||
    root
  );
}

function resolveNeckBone(vrm, root) {
  return (
    vrm?.humanoid?.getNormalizedBoneNode?.("neck") ||
    vrm?.humanoid?.getRawBoneNode?.("neck") ||
    root.getObjectByName("Neck") ||
    root.getObjectByName("neck") ||
    resolveHeadBone(vrm, root)
  );
}

function collectMorphBindings(root) {
  const bindings = new Map();
  const aliases = {
    jawOpen: ["jawopen", "jaw_open", "mouthopen", "mouth_open", "aa", "viseme_aa"],
    viseme_aa: ["viseme_aa", "aa", "a", "moutha"],
    viseme_ee: ["viseme_ee", "ee", "ih", "i", "mouthee"],
    viseme_oh: ["viseme_oh", "oh", "ou", "o", "mouthoh"],
    mouthPucker: ["mouthpucker", "pucker", "ou", "kiss"],
  };

  root.traverse((node) => {
    if (!node.isMesh || !node.morphTargetDictionary || !node.morphTargetInfluences) return;
    const entries = Object.entries(node.morphTargetDictionary);
    Object.entries(aliases).forEach(([controlName, names]) => {
      entries.forEach(([targetName, index]) => {
        const normalized = targetName.toLowerCase();
        if (!names.includes(normalized)) return;
        if (!bindings.has(controlName)) bindings.set(controlName, []);
        bindings.get(controlName).push({ mesh: node, index });
      });
    });
  });
  return bindings;
}

function buildIdleRig(vrm, root) {
  const lookup = {
    hips: resolveHumanoidBone(vrm, root, "hips", ["Hips", "hips"]),
    spine: resolveHumanoidBone(vrm, root, "spine", ["Spine", "spine"]),
    chest: resolveHumanoidBone(vrm, root, "chest", ["Chest", "chest", "UpperChest", "upperChest"]),
    upperChest: resolveHumanoidBone(vrm, root, "upperChest", ["UpperChest", "upperChest", "Chest", "chest"]),
    neck: resolveHumanoidBone(vrm, root, "neck", ["Neck", "neck"]),
    head: resolveHumanoidBone(vrm, root, "head", ["Head", "head"]),
    leftShoulder: resolveHumanoidBone(vrm, root, "leftShoulder", ["LeftShoulder", "leftShoulder", "Shoulder_L"]),
    rightShoulder: resolveHumanoidBone(vrm, root, "rightShoulder", ["RightShoulder", "rightShoulder", "Shoulder_R"]),
    leftUpperArm: resolveHumanoidBone(vrm, root, "leftUpperArm", ["LeftUpperArm", "leftUpperArm", "Arm_L"]),
    rightUpperArm: resolveHumanoidBone(vrm, root, "rightUpperArm", ["RightUpperArm", "rightUpperArm", "Arm_R"]),
    leftLowerArm: resolveHumanoidBone(vrm, root, "leftLowerArm", ["LeftLowerArm", "leftLowerArm", "ForeArm_L"]),
    rightLowerArm: resolveHumanoidBone(vrm, root, "rightLowerArm", ["RightLowerArm", "rightLowerArm", "ForeArm_R"]),
    leftHand: resolveHumanoidBone(vrm, root, "leftHand", ["LeftHand", "leftHand", "Hand_L"]),
    rightHand: resolveHumanoidBone(vrm, root, "rightHand", ["RightHand", "rightHand", "Hand_R"]),
  };

  const base = new Map();
  Object.values(lookup).forEach((bone) => {
    if (bone && !base.has(bone)) {
      base.set(bone, bone.quaternion.clone());
    }
  });

  return { bones: lookup, base };
}

function resolveHumanoidBone(vrm, root, humanoidName, fallbacks) {
  return (
    vrm?.humanoid?.getNormalizedBoneNode?.(humanoidName) ||
    vrm?.humanoid?.getRawBoneNode?.(humanoidName) ||
    fallbacks.map((name) => root.getObjectByName(name)).find(Boolean) ||
    null
  );
}

function applyProceduralIdlePose(time) {
  const rig = avatarState.idleRig;
  if (!rig) return;

  const breathe = Math.sin(time * 1.9) * 0.018;
  const sway = Math.sin(time * 1.15) * 0.05;
  const armDrift = Math.sin(time * 1.55) * 0.07;
  const forearmDrift = Math.sin(time * 1.55 + 0.8) * 0.06;
  const handDrift = Math.sin(time * 2.3) * 0.04;

  applyBoneRotation(rig.bones.hips, 0, sway * 0.08, sway * 0.04);
  applyBoneRotation(rig.bones.spine, breathe, sway * 0.18, sway * 0.06);
  applyBoneRotation(rig.bones.chest, breathe * 1.4, sway * 0.24, sway * 0.08);
  applyBoneRotation(rig.bones.upperChest, breathe * 1.6, sway * 0.28, sway * 0.1);

  applyBoneRotation(rig.bones.leftShoulder, 0.04, 0.03, -0.18);
  applyBoneRotation(rig.bones.rightShoulder, 0.04, -0.03, 0.18);
  applyBoneRotation(rig.bones.leftUpperArm, 0.12 + armDrift * 0.08, 0.03, -1.0);
  applyBoneRotation(rig.bones.rightUpperArm, 0.12 + armDrift * 0.08, -0.03, 1.0);
  applyBoneRotation(rig.bones.leftLowerArm, -0.14 + forearmDrift * 0.08, 0, -0.12);
  applyBoneRotation(rig.bones.rightLowerArm, -0.14 + forearmDrift * 0.08, 0, 0.12);
  applyBoneRotation(rig.bones.leftHand, handDrift * 0.2, 0, -0.05);
  applyBoneRotation(rig.bones.rightHand, handDrift * 0.2, 0, 0.05);
}

function applyBoneRotation(bone, x = 0, y = 0, z = 0) {
  if (!bone) return;
  const baseQuaternion = avatarState.idleRig?.base?.get(bone);
  if (baseQuaternion) {
    bone.quaternion.copy(baseQuaternion);
    TMP_EULER.set(x, y, z, "XYZ");
    TMP_QUATERNION.setFromEuler(TMP_EULER);
    bone.quaternion.multiply(TMP_QUATERNION);
    return;
  }
  bone.rotation.x = x;
  bone.rotation.y = y;
  bone.rotation.z = z;
}

async function checkHealth() {
  const res = await fetch("/health");
  const data = await res.json();
  statusEl.textContent = `状态：${toCnState(data.state)}`;
  outputEl.textContent = JSON.stringify(data, null, 2);
  sendBtn.disabled = !!data.pipeline_busy;
  updateMetrics(data);
}

function subscribeEvents() {
  if (evt) return;
  evt = new EventSource("/events");
  evt.onmessage = (event) => {
    try {
      const data = JSON.parse(event.data);
      statusEl.textContent = `状态：${toCnState(data.state)}`;
      outputEl.textContent = JSON.stringify(data, null, 2);
      sendBtn.disabled = !!data.pipeline_busy;
      updateMetrics(data);
    } catch (_) {
      // no-op
    }
  };
}

function subscribeSubtitles() {
  if (subtitleWs && (subtitleWs.readyState === WebSocket.OPEN || subtitleWs.readyState === WebSocket.CONNECTING)) return;
  const scheme = location.protocol === "https:" ? "wss" : "ws";
  subtitleWs = new WebSocket(`${scheme}://${location.host}/ws/subtitles`);
  subtitleWs.onmessage = (event) => {
    try {
      const data = JSON.parse(event.data);
      if (data.role === "user") {
        aiStreamingEl = null;
        addMessage(data.role, data.text || "");
      } else if (data.role === "ai") {
        if (data.partial) {
          if (!aiStreamingEl) aiStreamingEl = addMessage("ai", "");
          aiStreamingEl.textContent = `${aiStreamingEl.textContent}${data.text || ""}`;
          if (data.final) aiStreamingEl = null;
        } else {
          aiStreamingEl = null;
          addMessage("ai", data.text || "");
        }
      }
    } catch (_) {
      // no-op
    }
  };
  subtitleWs.onclose = () => {
    setTimeout(subscribeSubtitles, 1000);
  };
}

function subscribeAnimation() {
  if (animationWs && (animationWs.readyState === WebSocket.OPEN || animationWs.readyState === WebSocket.CONNECTING)) return;
  const scheme = location.protocol === "https:" ? "wss" : "ws";
  animationConn.textContent = "连接中";
  animationWs = new WebSocket(`${scheme}://${location.host}/ws/animation`);
  animationWs.onopen = () => {
    animationConn.textContent = "已连接";
  };
  animationWs.onmessage = (event) => {
    try {
      const data = JSON.parse(event.data);
      if (data.type === "ping") return;
      if (data.driver) {
        animationDriver.textContent = data.driver;
      }
      const frameCount = data.frame_count ?? data.frames?.length ?? 0;
      animationFrames.textContent = String(frameCount);
      const preview = data.frames?.[0]?.controls || null;
      animationPreview.textContent = preview ? JSON.stringify(preview, null, 2) : JSON.stringify(data, null, 2);
      queueAnimationFrames(data);
    } catch (_) {
      // no-op
    }
  };
  animationWs.onclose = () => {
    animationConn.textContent = "已断开";
    setTimeout(subscribeAnimation, 1000);
  };
}

async function connectWebRTC() {
  if (pc) {
    outputEl.textContent = "WebRTC 已连接或正在连接";
    return;
  }
  setConnBadge("连接中...", "warn");
  offerBtn.disabled = true;

  const metaRes = await fetch("/meta");
  const meta = await metaRes.json();
  pc = new RTCPeerConnection({
    iceServers: [{ urls: [meta.stun_url || "stun:stun.l.google.com:19302"] }],
  });
  const currentPc = pc;
  let seenConnected = false;

  currentPc.onconnectionstatechange = () => {
    const st = currentPc.connectionState;
    if (st === "connected") {
      seenConnected = true;
      setConnBadge("已连接", "ok");
      localStorage.setItem(AUTO_RECONNECT_KEY, "1");
    } else if (st === "connecting") {
      setConnBadge("连接中...", "warn");
    } else if (st === "failed" || st === "disconnected" || st === "closed") {
      setConnBadge(`连接${st}`, "warn");
      if (seenConnected && (st === "disconnected" || st === "failed")) {
        addMessage("system", "连接已断开，可能被新的客户端连接接管。");
      }
      if (localMicStream) {
        localMicStream.getTracks().forEach((track) => track.stop());
        localMicStream = null;
      }
      if (pc === currentPc) {
        pc = null;
      }
      offerBtn.disabled = false;
    }
  };

  pc.ontrack = (event) => {
    if (event.streams && event.streams[0]) {
      remoteAudio.srcObject = event.streams[0];
      remoteAudio.play().catch(() => {
        addMessage("system", "远端语音已到达，如未自动播放请先与页面交互后重试。");
      });
    }
  };

  let stream;
  try {
    stream = await navigator.mediaDevices.getUserMedia({ audio: true, video: false });
    localMicStream = stream;
  } catch (err) {
    statusEl.textContent = "状态：麦克风权限失败";
    outputEl.textContent = `getUserMedia 失败：${err?.message || err}\n提示：跨机器访问请使用 HTTPS 或浏览器安全例外。`;
    setConnBadge("麦克风失败", "warn");
    offerBtn.disabled = false;
    throw err;
  }

  stream.getTracks().forEach((track) => pc.addTrack(track, stream));
  const offer = await pc.createOffer();
  await pc.setLocalDescription(offer);

  const res = await fetch("/webrtc/offer", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      sdp: pc.localDescription.sdp,
      type: pc.localDescription.type,
    }),
  });
  const answer = await res.json();
  await pc.setRemoteDescription(answer);
  statusEl.textContent = "状态：WebRTC 已连接";
  outputEl.textContent = JSON.stringify({ connected: true, iceConnectionState: pc.iceConnectionState }, null, 2);
  setConnBadge("已连接", "ok");
  addMessage("system", "WebRTC 已连接，可开始对话。");
  if (answer.replaced_previous) {
    addMessage("system", "检测到已有旧连接，已自动断开旧连接并由当前页面接管。");
  }

  subscribeEvents();
}

async function sendText() {
  const text = (chatInput.value || "").trim();
  if (!text || sendBtn.disabled) return;
  sendBtn.disabled = true;
  const res = await fetch("/chat/text", {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ text }),
  });
  const data = await res.json();
  outputEl.textContent = JSON.stringify(data, null, 2);
  if (data.ok) {
    chatInput.value = "";
  } else if (data.message) {
    addMessage("system", `发送失败：${data.message}`);
  }
  sendBtn.disabled = false;
}

async function resetChat() {
  await fetch("/chat/reset", { method: "POST" });
  messagesEl.innerHTML = "";
  avatarState.pendingFrames = [];
  avatarState.scheduleCursorMs = performance.now() + ANIMATION_BUFFER_MS;
  resetAvatarPose();
  addMessage("system", "会话已重置。");
  await checkHealth();
}

function tryAutoReconnect() {
  if (localStorage.getItem(AUTO_RECONNECT_KEY) !== "1") return;
  setTimeout(() => {
    if (!pc) {
      connectWebRTC().catch(() => {
        // no-op
      });
    }
  }, 300);
}

function handleModelFileChange(event) {
  const [file] = event.target.files || [];
  if (!file) return;
  loadModelFromFile(file);
}

function handleModelUrlLoad() {
  const url = modelUrl.value.trim();
  if (!url) return;
  loadModelFromUrl(url);
}

new ResizeObserver(() => resizeStage()).observe(avatarCanvas);
window.addEventListener("resize", resizeStage);

healthBtn.addEventListener("click", checkHealth);
offerBtn.addEventListener("click", connectWebRTC);
resetBtn.addEventListener("click", resetChat);
sendBtn.addEventListener("click", sendText);
loadModelBtn.addEventListener("click", handleModelUrlLoad);
resetViewBtn.addEventListener("click", resetView);
modelFile.addEventListener("change", handleModelFileChange);
chatInput.addEventListener("keydown", (event) => {
  if (event.key === "Enter") {
    event.preventDefault();
    sendText();
  }
});
modelUrl.addEventListener("keydown", (event) => {
  if (event.key === "Enter") {
    event.preventDefault();
    handleModelUrlLoad();
  }
});

initStage();
resetView();
resetAvatarPose();
loadDefaultAvatarModel();
checkHealth();
subscribeEvents();
subscribeSubtitles();
subscribeAnimation();
setConnBadge("未连接", "neutral");
tryAutoReconnect();