const { WebSocket, WebSocketServer } = require('ws');
const url = require('url');
const db = require('../db');
const { correctAsrText } = require('./fastAsrCorrector');
const contextKeywordTracker = require('./contextKeywordTracker');
const { isBrandHarmful, getVoiceSafeReply, BRAND_HARMFUL_PATTERN, BRAND_POSITIVE_LEGALITY_PATTERN } = require('./contentSafeGuard');
const {
  MsgType,
  unmarshal,
  createStartConnectionMessage,
  createStartSessionMessage,
  createAudioMessage,
  createChatTTSTextMessage,
  createSayHelloMessage,
  createChatRAGTextMessage,
} = require('./realtimeDialogProtocol');
const {
  getRuleBasedDirectRouteDecision,
  normalizeKnowledgeAlias,
  normalizeTextForSpeech,
  splitTextForSpeech,
  estimateSpeechDurationMs,
  shouldForceKnowledgeRoute,
  resolveReply,
} = require('./realtimeDialogRouting');
const {
  DEFAULT_VOICE_ASSISTANT_PROFILE,
  resolveAssistantProfile,
  buildVoiceSystemRole,
  buildVoiceGreeting,
} = require('./assistantProfileConfig');

const sessions = new Map();

const IDLE_TIMEOUT_MS = 5 * 60 * 1000;

const DEFAULT_VOICE_BOT_NAME = DEFAULT_VOICE_ASSISTANT_PROFILE.nickname;

const DEFAULT_VOICE_SYSTEM_ROLE = buildVoiceSystemRole();

const DEFAULT_VOICE_SPEAKING_STYLE = '整体语气亲切自然、轻快有温度，像熟悉行业的朋友在语音聊天。优先短句和口语化表达，先给结论，再补一句最有帮助的信息。不要播音腔，不要念稿，不要客服腔，不要过度热情，也不要输出任何思考过程。';

const DEFAULT_VOICE_GREETING = buildVoiceGreeting();

function resetIdleTimer(session) {
  clearTimeout(session.idleTimer);
  session.lastActivityAt = Date.now();
  session.idleTimer = setTimeout(() => {
    session.idleTimer = null;
    console.log(`[NativeVoice] idle timeout (${IDLE_TIMEOUT_MS / 1000}s) session=${session.sessionId}`);
    sendJson(session.client, { type: 'idle_timeout', timeout: IDLE_TIMEOUT_MS });
    setTimeout(() => {
      if (session.client && session.client.readyState === WebSocket.OPEN) {
        session.client.close();
      }
    }, 2000);
  }, IDLE_TIMEOUT_MS);
}

function sendJson(ws, payload) {
  if (ws && ws.readyState === WebSocket.OPEN) {
    ws.send(JSON.stringify(payload));
  }
}

function buildStartSessionPayload(options) {
  const antiThinkingPrefix = '【最高优先级规则】你绝对禁止输出任何思考过程、分析、计划、角色扮演指令或元描述。禁止出现：“首轮对话”“应该回复”“需要列举”“语气要”“回复后询问”“可列举”“突出特色”“引导用户”“让用户”“用温和”等分析性、指令性语句。你必须直接用自然语言回答问题，像真人聊天一样直接说出答案内容。';
  const baseSystemRole = options.systemRole || DEFAULT_VOICE_SYSTEM_ROLE;
  const baseSpeakingStyle = options.speakingStyle || DEFAULT_VOICE_SPEAKING_STYLE;
  return {
    asr: {
      extra: {
        context: '一成,一成系统,大沃,PM,PM-FitLine,FitLine,细胞营养素,Ai众享,AI众享,盛咖学愿,数字化工作室,Activize,Basics,Restorate,NTC,基础三合一,招商,阿育吠陀,小红产品,小红,小白,大白,肽美,艾特维,德丽,德维,宝丽,美固健,Activize Oxyplus,Basic Power,CitrusCare,NutriSunny,Q10,Omega,葡萄籽,白藜芦醇,益生菌,胶原蛋白肽,Germany,FitLine细胞营养,FitLine营养素,德国PM营养素,德国PM FitLine,德国PM细胞营养,德国PM产品,德国PM健康,德国PM事业,德国PM招商,一成,一成团队,一成商学院,数字化,数字化运营,数字化经营,数字化营销,数字化创业,数字化工作室,数字化事业,招商加盟,合作加盟,事业合作',
        nbest: 1,
      },
    },
    tts: {
      speaker: options.speaker || process.env.VOLC_S2S_SPEAKER_ID || 'zh_female_vv_jupiter_bigtts',
      audio_config: {
        channel: 1,
        format: 'pcm_s16le',
        sample_rate: 24000,
      },
    },
    dialog: {
      dialog_id: '',
      bot_name: options.botName || '大沃',
      system_role: normalizeTextForSpeech(`${antiThinkingPrefix} ${baseSystemRole}`),
      speaking_style: normalizeTextForSpeech(baseSpeakingStyle),
      extra: {
        input_mod: 'audio',
        model: options.modelVersion || 'SC2.0',
        strict_audit: false,
        audit_response: '抱歉，这个问题我暂时无法回答。',
      },
    },
  };
}

function parseJsonPayload(message) {
  try {
    return JSON.parse(message.payload.toString('utf8'));
  } catch (error) {
    return null;
  }
}

function extractRawText(jsonPayload) {
  const text = jsonPayload?.text
    || jsonPayload?.content
    || jsonPayload?.results?.[0]?.text
    || jsonPayload?.results?.[0]?.alternatives?.[0]?.text
    || '';
  return String(text || '').trim();
}

function extractUserText(jsonPayload, sessionId = null) {
  let text = extractRawText(jsonPayload);
  text = correctAsrText(text);
  if (sessionId) {
    contextKeywordTracker.updateSession(sessionId, normalizeKnowledgeAlias(text));
  }
  return text;
}

const THINKING_PATTERN = /^(首轮对话|用户想|用户问|应该回复|需要列举|可列举|突出特色|引导进一步|引导用户|让用户|回复后询问|语气要|用温和|需热情|需简洁|需专业)/;
const THINKING_MID_PATTERN = /(?:需客观回复|应说明其|回复后询问|引导.*对话|用.*口吻回复|语气要.*热情|需要.*引导|应该.*回复|先.*再.*最后)/;

function sanitizeAssistantText(text) {
  if (!text) return text;
  if (isBrandHarmful(text)) {
    console.warn(`[NativeVoice][SafeGuard] blocked harmful content: ${JSON.stringify(text.slice(0, 200))}`);
    return getVoiceSafeReply();
  }
  if (THINKING_PATTERN.test(text.trim())) {
    console.warn(`[NativeVoice][SafeGuard] blocked thinking output: ${JSON.stringify(text.slice(0, 200))}`);
    return null;
  }
  return text;
}

function isFinalUserPayload(jsonPayload) {
  if (jsonPayload?.is_final === true) {
    return true;
  }
  if (Array.isArray(jsonPayload?.results)) {
    return jsonPayload.results.some((item) => item && item.is_interim === false);
  }
  return false;
}

function persistUserSpeech(session, text) {
  const cleanText = (text || '').trim();
  if (!cleanText) return false;
  const now = Date.now();
  if (session.lastPersistedUserText === cleanText && now - (session.lastPersistedUserAt || 0) < 5000) {
    return false;
  }
  session.lastPersistedUserText = cleanText;
  session.lastPersistedUserAt = now;
  session.latestUserText = cleanText;
  session.latestUserTurnSeq = (session.latestUserTurnSeq || 0) + 1;
  resetIdleTimer(session);
  db.addMessage(session.sessionId, 'user', cleanText, 'voice_asr').catch((e) => console.warn('[NativeVoice][DB] add user failed:', e.message));
  sendJson(session.client, {
    type: 'subtitle',
    role: 'user',
    text: cleanText,
    isFinal: true,
    sequence: `native_user_${now}`,
  });
  return true;
}

function persistAssistantSpeech(session, text, { source = 'voice_bot', toolName = null, persistToDb = true, meta = null } = {}) {
  const cleanText = sanitizeAssistantText((text || '').trim());
  if (!cleanText) return false;
  const now = Date.now();
  if (session.lastPersistedAssistantText === cleanText && now - (session.lastPersistedAssistantAt || 0) < 5000) {
    return false;
  }
  session.lastPersistedAssistantText = cleanText;
  session.lastPersistedAssistantAt = now;
  resetIdleTimer(session);
  if (persistToDb) {
    db.addMessage(session.sessionId, 'assistant', cleanText, source, toolName, meta).catch((e) => console.warn('[NativeVoice][DB] add assistant failed:', e.message));
  }
  sendJson(session.client, {
    type: 'subtitle',
    role: 'assistant',
    text: cleanText,
    isFinal: true,
    source,
    toolName,
    sequence: `native_assistant_${now}`,
  });
  return true;
}

function appendAssistantStream(session, payload) {
  const chunkText = extractRawText(payload);
  if (!chunkText) {
    return '';
  }
  const replyId = payload?.reply_id || '';
  if (replyId && session.assistantStreamReplyId && session.assistantStreamReplyId !== replyId) {
    session.assistantStreamBuffer = '';
  }
  session.assistantStreamReplyId = replyId || session.assistantStreamReplyId || '';
  session.assistantStreamBuffer = `${session.assistantStreamBuffer || ''}${chunkText}`;
  return session.assistantStreamBuffer;
}

function flushAssistantStream(session, { source = 'voice_bot', toolName = null, meta = null } = {}) {
  const fullText = (session.assistantStreamBuffer || '').trim();
  session.assistantStreamBuffer = '';
  session.assistantStreamReplyId = '';
  if (!fullText) {
    return false;
  }
  return persistAssistantSpeech(session, fullText, { source, toolName, meta });
}

async function loadHandoffSummaryForVoice(session) {
  try {
    const history = await db.getHistoryForLLM(session.sessionId, 10);
    if (!history.length) {
      session.handoffSummary = '';
      session.handoffSummaryUsed = false;
      return;
    }
    session.handoffSummary = buildDeterministicHandoffSummary(history);
    session.handoffSummaryUsed = false;
    console.log(`[NativeVoice] Handoff summary prepared for ${session.sessionId}: ${session.handoffSummary ? 'yes' : 'no'}`);
  } catch (error) {
    session.handoffSummary = '';
    session.handoffSummaryUsed = false;
    console.warn('[NativeVoice] loadHandoffSummaryForVoice failed:', error.message);
  }
}

function buildDeterministicHandoffSummary(messages = []) {
  const normalizedMessages = (Array.isArray(messages) ? messages : [])
    .filter((item) => item && (item.role === 'user' || item.role === 'assistant') && String(item.content || '').trim())
    .slice(-8);
  if (!normalizedMessages.length) {
    return '';
  }
  const userMessages = normalizedMessages.filter((item) => item.role === 'user');
  const currentQuestion = String(userMessages[userMessages.length - 1]?.content || '').trim();
  const previousQuestion = String(userMessages[userMessages.length - 2]?.content || '').trim();
  const assistantFacts = normalizedMessages
    .filter((item) => item.role === 'assistant')
    .slice(-2)
    .map((item) => String(item.content || '').trim())
    .filter(Boolean)
    .map((item) => item.slice(0, 60))
    .join('；');
  const parts = [];
  if (currentQuestion) {
    parts.push(`当前问题：${currentQuestion}`);
  }
  if (previousQuestion && previousQuestion !== currentQuestion) {
    parts.push(`上一轮关注：${previousQuestion}`);
  }
  if (assistantFacts) {
    parts.push(`已给信息：${assistantFacts}`);
  }
  return parts.join('；');
}

async function sendSpeechText(session, speechText) {
  const chunks = splitTextForSpeech(speechText);
  if (!chunks.length || !session.upstream || session.upstream.readyState !== WebSocket.OPEN) {
    return;
  }
  console.log(`[NativeVoice] sendSpeechText start session=${session.sessionId} chunks=${chunks.length} textLen=${speechText.length}`);
  session.currentSpeechText = speechText;
  session.isSendingChatTTSText = true;
  session.currentTtsType = 'chat_tts_text';
  session.chatTTSUntil = Date.now() + estimateSpeechDurationMs(speechText) + 800;
  clearTimeout(session.chatTTSTimer);
  session.chatTTSTimer = setTimeout(() => {
    session.chatTTSTimer = null;
    if ((session.chatTTSUntil || 0) <= Date.now()) {
      session.isSendingChatTTSText = false;
    }
  }, Math.max(200, session.chatTTSUntil - Date.now() + 50));
  sendJson(session.client, { type: 'tts_reset', ttsType: 'chat_tts_text' });
  for (let index = 0; index < chunks.length; index += 1) {
    const chunk = chunks[index];
    console.log(`[NativeVoice] sendSpeechText chunk session=${session.sessionId} index=${index + 1}/${chunks.length} len=${chunk.length} start=${index === 0} end=false text=${JSON.stringify(chunk.slice(0, 80))}`);
    session.upstream.send(createChatTTSTextMessage(session.sessionId, {
      start: index === 0,
      end: false,
      content: chunk,
    }));
  }
  console.log(`[NativeVoice] sendSpeechText end session=${session.sessionId}`);
  session.upstream.send(createChatTTSTextMessage(session.sessionId, {
    start: false,
    end: true,
    content: '',
  }));
}

 function sendReady(session) {
   if (session.readySent) {
     return;
   }
   session.readySent = true;
   sendJson(session.client, { type: 'ready' });
 }

 function sendGreeting(session) {
  if (session.hasSentGreeting) {
    sendReady(session);
    return;
  }
  session.hasSentGreeting = true;
  const greetingText = session.greetingText || DEFAULT_VOICE_GREETING;
  console.log(`[NativeVoice] sendGreeting session=${session.sessionId} text=${JSON.stringify(greetingText.slice(0, 80))}`);
  persistAssistantSpeech(session, greetingText, { source: 'voice_bot' });
  clearTimeout(session.greetingTimer);
  clearTimeout(session.readyTimer);
  session.greetingSentAt = Date.now();
  session.greetingProtectionUntil = Date.now() + 2000;
  session.currentSpeechText = greetingText;
  try {
    session.upstream.send(createSayHelloMessage(session.sessionId, greetingText));
    console.log(`[NativeVoice] sendSayHello event=300 session=${session.sessionId}`);
  } catch (error) {
    session.hasSentGreeting = false;
    session.greetingProtectionUntil = 0;
    console.warn('[NativeVoice] SayHello failed:', error.message);
  }
  sendReady(session);
}

async function replayGreeting(session) {
  const greetingText = String(session.greetingText || '').trim();
  if (!greetingText || !session.upstream || session.upstream.readyState !== WebSocket.OPEN) {
    return;
  }
  if (session.greetingSentAt && Date.now() - session.greetingSentAt < 6000) {
    console.log(`[NativeVoice] replayGreeting skipped (too soon) session=${session.sessionId}`);
    return;
  }
  console.log(`[NativeVoice] replayGreeting session=${session.sessionId} text=${JSON.stringify(greetingText.slice(0, 80))}`);
  session.greetingSentAt = Date.now();
  session.directSpeakUntil = Date.now() + estimateSpeechDurationMs(greetingText) + 800;
  try {
    session.upstream.send(createSayHelloMessage(session.sessionId, greetingText));
  } catch (error) {
    console.warn('[NativeVoice] replayGreeting SayHello failed:', error.message);
  }
}

async function sendExternalRag(session, items) {
  if (!session.upstream || session.upstream.readyState !== WebSocket.OPEN) {
    return;
  }
  const ragItems = Array.isArray(items) ? items.filter((item) => item && item.content) : [];
  if (!ragItems.length) {
    return;
  }
  session.upstream.send(createChatRAGTextMessage(session.sessionId, JSON.stringify(ragItems)));
}

function clearUpstreamSuppression(session) {
  clearTimeout(session.suppressReplyTimer);
  session.suppressReplyTimer = null;
  session.suppressUpstreamUntil = 0;
  session.awaitingUpstreamReply = false;
  session.pendingAssistantSource = null;
  session.pendingAssistantToolName = null;
  session.pendingAssistantMeta = null;
  session.pendingAssistantTurnSeq = 0;
  session.blockUpstreamAudio = false;
  sendJson(session.client, { type: 'assistant_pending', active: false });
}

function suppressUpstreamReply(session, durationMs) {
  clearTimeout(session.suppressReplyTimer);
  session.awaitingUpstreamReply = true;
  session.suppressUpstreamUntil = Date.now() + Math.max(1000, durationMs);
  session.suppressReplyTimer = setTimeout(() => {
    session.suppressReplyTimer = null;
    if ((session.suppressUpstreamUntil || 0) > Date.now()) {
      return;
    }
    clearUpstreamSuppression(session);
  }, Math.max(300, session.suppressUpstreamUntil - Date.now()));
}

async function processReply(session, text, turnSeq = session.latestUserTurnSeq || 0) {
  const cleanText = (text || '').trim();
  if (!cleanText) return;
  if (session.processingReply) {
    session.queuedUserText = cleanText;
    session.queuedUserTurnSeq = turnSeq;
    console.log(`[NativeVoice] processReply queued(busy) session=${session.sessionId} text=${JSON.stringify(cleanText.slice(0, 80))}`);
    return;
  }
  const now = Date.now();
  if (session.directSpeakUntil && now < session.directSpeakUntil) {
    session.queuedUserText = cleanText;
    session.queuedUserTurnSeq = turnSeq;
    console.log(`[NativeVoice] processReply queued(speaking) session=${session.sessionId} waitMs=${session.directSpeakUntil - now} text=${JSON.stringify(cleanText.slice(0, 80))}`);
    return;
  }
  const activeTurnSeq = turnSeq || session.latestUserTurnSeq || 0;
  session.processingReply = true;
  sendJson(session.client, { type: 'assistant_pending', active: true });
  let isKnowledgeCandidate = shouldForceKnowledgeRoute(cleanText);
  // KB话题保护窗口：最近60秒内有KB hit，当前轮不是纯闲聊/告别，也视为KB候选
  // 防止用户质疑/纠正产品信息时S2S自由编造（如"粉末来的呀你搞错了吧"）
  const KB_PROTECTION_WINDOW_MS = 60000;
  if (!isKnowledgeCandidate && session._lastKbHitAt && (Date.now() - session._lastKbHitAt < KB_PROTECTION_WINDOW_MS)) {
    const isPureChitchat = /^(喂|你好|嗨|谢谢|再见|拜拜|好的|嗯|哦|行|没事了|不用了|可以了)[，,。！？\s]*$/.test(cleanText);
    if (!isPureChitchat) {
      isKnowledgeCandidate = true;
      console.log(`[NativeVoice] KB protection window active, promoting to kbCandidate session=${session.sessionId} lastKbHit=${Math.round((Date.now() - session._lastKbHitAt) / 1000)}s ago`);
    }
  }
  if (isKnowledgeCandidate) {
    session.blockUpstreamAudio = true;
    suppressUpstreamReply(session, 30000);
    sendJson(session.client, { type: 'tts_reset', reason: 'processing' });
    // 过渡语已移除：KB查询优化后延迟已降至~2.6s，无需填充
    session._fillerActive = false;
  }
  console.log(`[NativeVoice] processReply start session=${session.sessionId} text=${JSON.stringify(cleanText.slice(0, 120))} blocked=${session.blockUpstreamAudio} kbCandidate=${isKnowledgeCandidate}`);
  try {
    // KB预查缓存消费：如果partial阶段已启动预查且文本匹配，直接使用缓存结果
    let resolveResult = null;
    if (isKnowledgeCandidate && session.pendingKbPrequery && session._kbPrequeryText) {
      const preText = (session._kbPrequeryText || '').replace(/[啊哦嗯呢呀哎诶额，。！？、,.\s]/g, '');
      const finalText = cleanText.replace(/[啊哦嗯呢呀哎诶额，。！？、,.\s]/g, '');
      // 放宽相似度：子串包含 或 重叠字符占比>=60% 即视为匹配
      let isSimilar = preText && finalText && (finalText.includes(preText) || preText.includes(finalText));
      if (!isSimilar && preText && finalText) {
        const shorter = preText.length <= finalText.length ? preText : finalText;
        const longer = preText.length <= finalText.length ? finalText : preText;
        let overlap = 0;
        for (let i = 0; i < shorter.length; i++) {
          if (longer.includes(shorter[i])) overlap++;
        }
        isSimilar = overlap / shorter.length >= 0.45;
      }
      if (isSimilar) {
        console.log(`[NativeVoice] using KB prequery cache session=${session.sessionId} preText=${JSON.stringify(session._kbPrequeryText.slice(0, 60))}`);
        resolveResult = await session.pendingKbPrequery;
      } else {
        console.log(`[NativeVoice] KB prequery text mismatch, re-querying session=${session.sessionId} pre=${JSON.stringify(preText.slice(0, 40))} final=${JSON.stringify(finalText.slice(0, 40))}`);
      }
    }
    session.pendingKbPrequery = null;
    session._kbPrequeryText = '';
    session._kbPrequeryStartedAt = 0;
    if (!resolveResult) {
      resolveResult = await resolveReply(session.sessionId, session, cleanText);
    }
    const { delivery, speechText, ragItems, source, toolName, routeDecision, responseMeta } = resolveResult;
    if (activeTurnSeq !== (session.latestUserTurnSeq || 0)) {
      console.log(`[NativeVoice] stale reply ignored session=${session.sessionId} activeTurn=${activeTurnSeq} latestTurn=${session.latestUserTurnSeq || 0}`);
      clearUpstreamSuppression(session);
      return;
    }
    if (delivery === 'upstream_chat') {
      if (isKnowledgeCandidate) {
        console.log(`[NativeVoice] processReply kb-nohit retrigger session=${session.sessionId}`);
        session.discardNextAssistantResponse = true;
        await sendExternalRag(session, [{ title: '用户问题', content: cleanText }]);
      } else {
        session.blockUpstreamAudio = false;
      }
      session._lastPartialAt = 0;
      session.awaitingUpstreamReply = true;
      session.pendingAssistantSource = 'voice_bot';
      session.pendingAssistantToolName = null;
      session.pendingAssistantMeta = responseMeta;
      session.pendingAssistantTurnSeq = activeTurnSeq;
      console.log(`[NativeVoice] processReply handoff session=${session.sessionId} route=${routeDecision?.route || 'unknown'} delivery=upstream_chat`);
      return;
    }
    if (delivery === 'external_rag') {
      if (!session.blockUpstreamAudio) {
        session.blockUpstreamAudio = true;
      }
      session.discardNextAssistantResponse = true;
      sendJson(session.client, { type: 'tts_reset', reason: 'knowledge_hit' });
      const ragContent = (ragItems || []).filter((item) => item && item.content);
      if (ragContent.length > 0) {
        console.log(`[NativeVoice] processReply sending external_rag to S2S session=${session.sessionId} route=${routeDecision?.route || 'unknown'} items=${ragContent.length}`);
        // KB话题记忆：记录本轮用户原始问题和时间戳，用于保护窗口和追问enrichment
        if (responseMeta?.hit !== false && responseMeta?.reason !== 'honest_fallback') {
          session._lastKbTopic = cleanText;
          session._lastKbHitAt = Date.now();
        }
        session._pendingExternalRagReply = true;
        await sendExternalRag(session, ragContent);
        session.awaitingUpstreamReply = true;
        session.pendingAssistantSource = source;
        session.pendingAssistantToolName = toolName;
        session.pendingAssistantMeta = responseMeta;
        session.pendingAssistantTurnSeq = activeTurnSeq;
      } else {
        console.log(`[NativeVoice] processReply external_rag empty content, fallback to upstream session=${session.sessionId}`);
        session.blockUpstreamAudio = false;
        clearUpstreamSuppression(session);
      }
      return;
    }
    if (!speechText) {
      console.log(`[NativeVoice] processReply empty session=${session.sessionId} route=${routeDecision?.route || 'unknown'} delivery=${delivery || 'unknown'}`);
      session.isSendingChatTTSText = false;
      session.chatTTSUntil = 0;
      return;
    }
    console.log(`[NativeVoice] processReply resolved session=${session.sessionId} route=${routeDecision?.route || 'unknown'} delivery=local_tts source=${source} tool=${toolName || 'chat'} speechLen=${speechText.length}`);
    session.directSpeakUntil = Date.now() + estimateSpeechDurationMs(speechText) + 800;
    suppressUpstreamReply(session, estimateSpeechDurationMs(speechText) + 1800);
    session.lastDeliveredAssistantTurnSeq = activeTurnSeq;
    persistAssistantSpeech(session, speechText, { source, toolName, meta: responseMeta });
    await sendSpeechText(session, speechText);
  } catch (error) {
    console.error('[NativeVoice] processReply failed:', error.message);
    sendJson(session.client, { type: 'error', error: error.message });
  } finally {
    session.processingReply = false;
    if (!session.awaitingUpstreamReply) {
      session.blockUpstreamAudio = false;
    }
    if (!session.awaitingUpstreamReply) {
      sendJson(session.client, { type: 'assistant_pending', active: false });
    }
    const pending = session.queuedUserText;
    const pendingTurnSeq = session.queuedUserTurnSeq || 0;
    session.queuedUserText = '';
    session.queuedUserTurnSeq = 0;
    if (pending && pendingTurnSeq && pendingTurnSeq !== activeTurnSeq && (!session.directSpeakUntil || Date.now() >= session.directSpeakUntil)) {
      setTimeout(() => {
        session.blockUpstreamAudio = true;
        processReply(session, pending, pendingTurnSeq).catch((err) => {
          console.error('[NativeVoice] queued processReply failed:', err.message);
        });
      }, 200);
    } else if (pending && pendingTurnSeq && pendingTurnSeq !== activeTurnSeq) {
      const waitMs = Math.max(200, session.directSpeakUntil - Date.now() + 200);
      clearTimeout(session.queuedReplyTimer);
      session.queuedReplyTimer = setTimeout(() => {
        session.queuedReplyTimer = null;
        const queuedText = session.queuedUserText || pending;
        const queuedTurnSeq = session.queuedUserTurnSeq || pendingTurnSeq;
        session.queuedUserText = '';
        session.queuedUserTurnSeq = 0;
        session.blockUpstreamAudio = true;
        processReply(session, queuedText, queuedTurnSeq).catch((err) => {
          console.error('[NativeVoice] delayed queued processReply failed:', err.message);
        });
      }, waitMs);
    }
  }
}

function handleUpstreamMessage(session, data) {
  let message;
  try {
    message = unmarshal(data);
  } catch (error) {
    console.warn('[NativeVoice] unmarshal failed:', error.message);
    return;
  }

  if (message.type === MsgType.AUDIO_ONLY_SERVER) {
    const isDefaultTts = !session.currentTtsType || session.currentTtsType === 'default';
    const isSuppressingUpstreamAudio = (session.suppressUpstreamUntil || 0) > Date.now() && isDefaultTts;
    // 用户刚停止说话后短暂阻止默认TTS音频，给event 459的blockUpstreamAudio留时间生效
    const isUserJustSpeaking = isDefaultTts && session._lastPartialAt && (Date.now() - session._lastPartialAt < 800);
    // blockUpstreamAudio 生效时：仅放行 external_rag 和限时过渡语音频，其余全部阻断
    // 修复：旧逻辑只阻断 isDefaultTts，导致 chat_tts_text 窗口期 S2S 自主回复音频泄漏
    const isBlockPassthrough = session.currentTtsType === 'external_rag' ||
      (session._fillerActive && (session.chatTTSUntil || 0) > Date.now());
    if ((session.blockUpstreamAudio && !isBlockPassthrough) || isSuppressingUpstreamAudio || isUserJustSpeaking) {
      if (!session._audioBlockLogOnce) {
        session._audioBlockLogOnce = true;
        console.log(`[NativeVoice] audio blocked session=${session.sessionId} ttsType=${session.currentTtsType} block=${session.blockUpstreamAudio} suppress=${isSuppressingUpstreamAudio}`);
      }
      return;
    }
    session._audioBlockLogOnce = false;
    if (session.client && session.client.readyState === WebSocket.OPEN) {
      session.client.send(message.payload, { binary: true });
    }
    return;
  }

  const payload = parseJsonPayload(message);
  if (message.type === MsgType.ERROR) {
    console.error(`[NativeVoice] upstream error session=${session.sessionId} code=${message.event} payload=${message.payload.toString('utf8').slice(0, 200)}`);
    sendJson(session.client, { type: 'error', error: message.payload.toString('utf8') });
    return;
  }

  if (message.type !== MsgType.FULL_SERVER) {
    return;
  }

  if (message.event === 150) {
    session.upstreamReady = true;
    console.log(`[NativeVoice] upstream ready session=${session.sessionId}`);
    resetIdleTimer(session);
    sendGreeting(session);
    return;
  }

  if (message.event === 300) {
    console.log(`[NativeVoice] SayHello response session=${session.sessionId}`);
    return;
  }

  if (message.event === 350) {
    session.currentTtsType = payload?.tts_type || '';
    if (payload?.tts_type === 'chat_tts_text' && session.pendingGreetingAck) {
      session.pendingGreetingAck = false;
      clearTimeout(session.greetingAckTimer);
      session.greetingAckTimer = null;
    }
    if (session.blockUpstreamAudio && payload?.tts_type === 'external_rag') {
      session.blockUpstreamAudio = false;
      session.suppressUpstreamUntil = 0;
      clearTimeout(session.suppressReplyTimer);
      session.suppressReplyTimer = null;
      // 注意：不清除discardNextAssistantResponse，让它拦截S2S默认回复的残留event 351
      // 该标记会在KB回复的event 550 chunks到达时自动清除
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      // 清除过渡语的chat TTS状态，确保external_rag回复不被isLocalChatTTSTextActive拦截
      session.isSendingChatTTSText = false;
      session.chatTTSUntil = 0;
      session.currentSpeechText = '';
      session._fillerActive = false;
      clearTimeout(session.chatTTSTimer);
      sendJson(session.client, { type: 'tts_reset', reason: 'rag_response_start' });
      console.log(`[NativeVoice] unblock for external_rag tts session=${session.sessionId}`);
    } else if (session.blockUpstreamAudio && payload?.tts_type === 'chat_tts_text') {
      console.log(`[NativeVoice] chat_tts_text started, keeping block for S2S default response session=${session.sessionId}`);
    }
    console.log(`[NativeVoice] upstream tts_event session=${session.sessionId} ttsType=${payload?.tts_type || ''}`);
    sendJson(session.client, { type: 'tts_event', payload });
    return;
  }

  const isLocalChatTTSTextActive = !!session.isSendingChatTTSText && (session.chatTTSUntil || 0) > Date.now();
  const isSuppressingUpstreamReply = (session.suppressUpstreamUntil || 0) > Date.now();

  if (message.event === 351) {
    if (isLocalChatTTSTextActive || session.blockUpstreamAudio || isSuppressingUpstreamReply) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      return;
    }
    if (session.discardNextAssistantResponse) {
      session.discardNextAssistantResponse = false;
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      console.log(`[NativeVoice] discarded stale assistant response (kb-nohit retrigger) session=${session.sessionId}`);
      return;
    }
    const pendingAssistantSource = session.pendingAssistantSource || 'voice_bot';
    const pendingAssistantToolName = session.pendingAssistantToolName || null;
    const pendingAssistantMeta = session.pendingAssistantMeta || null;
    const pendingAssistantTurnSeq = session.pendingAssistantTurnSeq || session.latestUserTurnSeq || 0;
    session.awaitingUpstreamReply = false;
    sendJson(session.client, { type: 'assistant_pending', active: false });
    if (pendingAssistantTurnSeq && session.lastDeliveredAssistantTurnSeq === pendingAssistantTurnSeq) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      session.pendingAssistantSource = null;
      session.pendingAssistantToolName = null;
      session.pendingAssistantMeta = null;
      console.log(`[NativeVoice] duplicate assistant final ignored (351) session=${session.sessionId} turn=${pendingAssistantTurnSeq}`);
      return;
    }
    const assistantText = extractRawText(payload);
    if (assistantText) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      // 过渡语的event 351：不持久化，直接丢弃
      if (session._fillerActive) {
        console.log(`[NativeVoice] discarded filler assistant text session=${session.sessionId}`);
        session._fillerActive = false;
        return;
      }
      // 清除external_rag等待标记，KB回复已到达
      if (session._pendingExternalRagReply) {
        session._pendingExternalRagReply = false;
      }
      // 品牌安全检测：最终助手文本包含有害内容时，阻断音频并注入安全回复
      if (isBrandHarmful(assistantText)) {
        console.warn(`[NativeVoice][SafeGuard] harmful content in final assistant text, blocking session=${session.sessionId} text=${JSON.stringify(assistantText.slice(0, 120))}`);
        session.blockUpstreamAudio = true;
        sendJson(session.client, { type: 'tts_reset', reason: 'harmful_blocked' });
        const safeReply = getVoiceSafeReply();
        session.lastDeliveredAssistantTurnSeq = pendingAssistantTurnSeq;
        persistAssistantSpeech(session, safeReply, { source: 'voice_bot' });
        sendSpeechText(session, safeReply).catch((err) => {
          console.warn('[NativeVoice][SafeGuard] sendSpeechText failed:', err.message);
        });
      } else {
        console.log(`[NativeVoice] upstream assistant session=${session.sessionId} text=${JSON.stringify(assistantText.slice(0, 120))}`);
        session.lastDeliveredAssistantTurnSeq = pendingAssistantTurnSeq;
        persistAssistantSpeech(session, assistantText, {
          source: pendingAssistantSource,
          toolName: pendingAssistantToolName,
          meta: pendingAssistantMeta,
        });
        // KB回复完成后重新阻断音频，防止下一个问题的S2S默认回复在early block前泄露
        if (session.currentTtsType === 'external_rag') {
          session.blockUpstreamAudio = true;
          console.log(`[NativeVoice] re-blocked after KB response session=${session.sessionId}`);
        }
      }
    } else {
      const didFlush = flushAssistantStream(session, {
        source: pendingAssistantSource,
        toolName: pendingAssistantToolName,
        meta: pendingAssistantMeta,
      });
      if (didFlush) {
        session.lastDeliveredAssistantTurnSeq = pendingAssistantTurnSeq;
      }
    }
    session.pendingAssistantSource = null;
    session.pendingAssistantToolName = null;
    session.pendingAssistantMeta = null;
    return;
  }

  if (message.event === 550) {
    // external_rag chunks到达时，清除discardNextAssistantResponse（默认回复的351已过或不会来）
    if (session.discardNextAssistantResponse && session.currentTtsType === 'external_rag') {
      session.discardNextAssistantResponse = false;
      console.log(`[NativeVoice] cleared discardNextAssistantResponse for external_rag stream session=${session.sessionId}`);
    }
    if (isLocalChatTTSTextActive || session.blockUpstreamAudio || isSuppressingUpstreamReply || session.discardNextAssistantResponse) {
      return;
    }
    if (session.awaitingUpstreamReply) {
      session.awaitingUpstreamReply = false;
      sendJson(session.client, { type: 'assistant_pending', active: false });
    }
    const fullText = appendAssistantStream(session, payload);
    if (fullText) {
      // 品牌安全检测：S2S模型输出传销等负面内容时，立即阻断音频并注入安全回复
      if (fullText.length >= 4 && isBrandHarmful(fullText)) {
        console.warn(`[NativeVoice][SafeGuard] harmful content detected in stream, blocking audio session=${session.sessionId} text=${JSON.stringify(fullText.slice(0, 120))}`);
        session.blockUpstreamAudio = true;
        session.discardNextAssistantResponse = true;
        session.assistantStreamBuffer = '';
        session.assistantStreamReplyId = '';
        sendJson(session.client, { type: 'tts_reset', reason: 'harmful_blocked' });
        // 注入安全回复语音，替代有害内容
        const safeReply = getVoiceSafeReply();
        persistAssistantSpeech(session, safeReply, { source: 'voice_bot' });
        sendSpeechText(session, safeReply).catch((err) => {
          console.warn('[NativeVoice][SafeGuard] sendSpeechText failed:', err.message);
        });
        return;
      }
      // 检测思考模式：S2S模型输出分析/计划而非直接回答，立即阻断
      if (fullText.length >= 10 && (THINKING_PATTERN.test(fullText.trim()) || THINKING_MID_PATTERN.test(fullText))) {
        console.warn(`[NativeVoice][SafeGuard] thinking detected in stream, blocking audio session=${session.sessionId} text=${JSON.stringify(fullText.slice(0, 120))}`);
        session.blockUpstreamAudio = true;
        session.discardNextAssistantResponse = true;
        session.assistantStreamBuffer = '';
        session.assistantStreamReplyId = '';
        sendJson(session.client, { type: 'tts_reset', reason: 'thinking_blocked' });
        return;
      }
      console.log(`[NativeVoice] upstream assistant chunk session=${session.sessionId} len=${fullText.length} text=${JSON.stringify(fullText.slice(0, 120))}`);
    }
    return;
  }

  if (message.event === 559) {
    if (isLocalChatTTSTextActive || isSuppressingUpstreamReply) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      return;
    }
    if (session.blockUpstreamAudio) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      console.log(`[NativeVoice] blocked response ended (559), keeping block session=${session.sessionId}`);
      return;
    }
    if (session.discardNextAssistantResponse) {
      session.discardNextAssistantResponse = false;
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      console.log(`[NativeVoice] discarded stale stream end (559, kb-nohit retrigger) session=${session.sessionId}`);
      return;
    }
    // external_rag流期间，阻止默认回复的559过早flush部分KB文本
    if (session._pendingExternalRagReply) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      console.log(`[NativeVoice] suppressed 559 flush during external_rag flow session=${session.sessionId}`);
      return;
    }
    const pendingAssistantTurnSeq = session.pendingAssistantTurnSeq || session.latestUserTurnSeq || 0;
    if (pendingAssistantTurnSeq && session.lastDeliveredAssistantTurnSeq === pendingAssistantTurnSeq) {
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      session.pendingAssistantSource = null;
      session.pendingAssistantToolName = null;
      session.pendingAssistantMeta = null;
      console.log(`[NativeVoice] duplicate assistant final ignored (559) session=${session.sessionId} turn=${pendingAssistantTurnSeq}`);
      return;
    }
    session.awaitingUpstreamReply = false;
    session.blockUpstreamAudio = false;
    sendJson(session.client, { type: 'assistant_pending', active: false });
    const didFlush = flushAssistantStream(session, {
      source: session.pendingAssistantSource || 'voice_bot',
      toolName: session.pendingAssistantToolName || null,
      meta: session.pendingAssistantMeta || null,
    });
    if (didFlush) {
      session.lastDeliveredAssistantTurnSeq = pendingAssistantTurnSeq;
    }
    session.pendingAssistantSource = null;
    session.pendingAssistantToolName = null;
    session.pendingAssistantMeta = null;
    return;
  }

  if (message.event === 450 || (message.event === 451 && !isFinalUserPayload(payload))) {
    const text = extractUserText(payload, session.sessionId);
    if (text) {
      const now = Date.now();
      const isDirectSpeaking = session.directSpeakUntil && now < session.directSpeakUntil;
      const isChatTTSSpeaking = session.isSendingChatTTSText && (session.chatTTSUntil || 0) > now;
      // TTS回声检测：播放期间如果ASR识别文本是当前播放文本的子串，判定为回声，忽略
      if ((isDirectSpeaking || isChatTTSSpeaking) && session.currentSpeechText) {
        const normalizedPartial = text.replace(/[，。！？、,.\s]/g, '');
        const normalizedSpeech = session.currentSpeechText.replace(/[，。！？、,.\s]/g, '');
        if (normalizedPartial.length <= 3 || normalizedSpeech.includes(normalizedPartial)) {
          if (!session._echoLogOnce) {
            session._echoLogOnce = true;
            console.log(`[NativeVoice] TTS echo detected, ignoring partial session=${session.sessionId} text=${JSON.stringify(text.slice(0, 80))}`);
          }
          return;
        }
        session._echoLogOnce = false;
      } else {
        session._echoLogOnce = false;
      }
      // Greeting保护窗口：发送问候语后短暂保护期内忽略barge-in
      if (session.greetingProtectionUntil && now < session.greetingProtectionUntil) {
        console.log(`[NativeVoice] greeting protection active, ignoring partial session=${session.sessionId} text=${JSON.stringify(text.slice(0, 80))}`);
        return;
      }
      console.log(`[NativeVoice] upstream partial session=${session.sessionId} text=${JSON.stringify(text.slice(0, 120))}`);
      const normalizedPartial = normalizeKnowledgeAlias(text);
      session.latestUserText = normalizedPartial;
      session._lastPartialAt = now;
      // 提前阻断：部分识别文字含知识库关键词时，立即阻断S2S音频，防止有害内容播出
      if (normalizedPartial.length >= 6 && !session.blockUpstreamAudio && shouldForceKnowledgeRoute(normalizedPartial)) {
        session.blockUpstreamAudio = true;
        session.currentTtsType = 'default';
        // 立即清除客户端已收到的S2S音频，防止用户听到抢答片段
        sendJson(session.client, { type: 'tts_reset', reason: 'early_block' });
        console.log(`[NativeVoice] early block: partial text matched KB keywords session=${session.sessionId} text=${JSON.stringify(text.slice(0, 80))}`);
        // KB预查询：提前启动知识库查询，减少final ASR后的等待时间
        const kbPrequeryDebounce = 600;
        if (normalizedPartial.length >= 8 && (!session._kbPrequeryStartedAt || now - session._kbPrequeryStartedAt > kbPrequeryDebounce)) {
          session._kbPrequeryStartedAt = now;
          session._kbPrequeryText = normalizedPartial;
          console.log(`[NativeVoice] KB prequery started session=${session.sessionId} text=${JSON.stringify(normalizedPartial.slice(0, 80))}`);
          session.pendingKbPrequery = resolveReply(session.sessionId, session, normalizedPartial).catch((err) => {
            console.warn(`[NativeVoice] KB prequery failed session=${session.sessionId}:`, err.message);
            return null;
          });
        }
      }
      // 用户开口说话时立即打断所有 AI 播放（包括 S2S 默认 TTS）
      if (isDirectSpeaking || isChatTTSSpeaking) {
        console.log(`[NativeVoice] user barge-in (partial) session=${session.sessionId} direct=${isDirectSpeaking} chatTTS=${isChatTTSSpeaking}`);
        session.directSpeakUntil = 0;
        session.isSendingChatTTSText = false;
        session.chatTTSUntil = 0;
        session.currentSpeechText = '';
        clearTimeout(session.chatTTSTimer);
        if (session.suppressReplyTimer || session.suppressUpstreamUntil) {
          clearUpstreamSuppression(session);
        }
      }
      // 无论当前是否在播放，都发送 tts_reset 确保客户端停止所有音频播放
      if (!session._lastBargeInResetAt || now - session._lastBargeInResetAt > 500) {
        session._lastBargeInResetAt = now;
        sendJson(session.client, { type: 'tts_reset', reason: 'user_bargein' });
      }
      sendJson(session.client, {
        type: 'subtitle',
        role: 'user',
        text: text,
        isFinal: false,
        sequence: `native_partial_${Date.now()}`,
      });
    }
    return;
  }

  if (message.event === 459 || (message.event === 451 && isFinalUserPayload(payload))) {
    const rawFinalText = extractUserText(payload, session.sessionId) || '';
    const finalText = normalizeKnowledgeAlias(rawFinalText) || session.latestUserText || '';
    const now459 = Date.now();
    // 双事件去重：S2S可能同时发送event 459和event 451(is_final)，用去标点归一化文本+时间窗口去重
    const normalizedForDedup = finalText.replace(/[，。！？、,.?!\s]/g, '');
    if (normalizedForDedup && session._lastFinalNormalized === normalizedForDedup && now459 - (session._lastFinalAt || 0) < 1500) {
      console.log(`[NativeVoice] duplicate final ignored (event=${message.event}) session=${session.sessionId} text=${JSON.stringify(finalText.slice(0, 80))}`);
      return;
    }
    session._lastFinalNormalized = normalizedForDedup;
    session._lastFinalAt = now459;
    // TTS回声检测（final级别）：播放期间ASR最终识别文本如果是当前播放文本的子串，判定为回声
    const isDirectSpeaking459 = session.directSpeakUntil && now459 < session.directSpeakUntil;
    const isChatTTSSpeaking459 = session.isSendingChatTTSText && (session.chatTTSUntil || 0) > now459;
    if ((isDirectSpeaking459 || isChatTTSSpeaking459) && session.currentSpeechText && finalText) {
      const normalizedFinal = finalText.replace(/[，。！？、,.\s]/g, '');
      const normalizedSpeech = session.currentSpeechText.replace(/[，。！？、,.\s]/g, '');
      if (normalizedFinal.length <= 4 || normalizedSpeech.includes(normalizedFinal)) {
        console.log(`[NativeVoice] TTS echo detected in final, ignoring session=${session.sessionId} text=${JSON.stringify(finalText.slice(0, 80))}`);
        return;
      }
    }
    // Greeting保护窗口
    if (session.greetingProtectionUntil && now459 < session.greetingProtectionUntil && finalText) {
      console.log(`[NativeVoice] greeting protection active, ignoring final session=${session.sessionId} text=${JSON.stringify(finalText.slice(0, 80))}`);
      return;
    }
    console.log(`[NativeVoice] upstream final session=${session.sessionId} text=${JSON.stringify(finalText.slice(0, 120))}`);
    if (session.directSpeakUntil && Date.now() < session.directSpeakUntil) {
      console.log(`[NativeVoice] user interrupt during speaking session=${session.sessionId}`);
      session.directSpeakUntil = 0;
      session.isSendingChatTTSText = false;
      session.chatTTSUntil = 0;
      session.currentSpeechText = '';
      clearTimeout(session.chatTTSTimer);
      sendJson(session.client, { type: 'tts_reset', reason: 'user_bargein' });
      if (session.suppressReplyTimer || session.suppressUpstreamUntil) {
        clearUpstreamSuppression(session);
      }
    } else if (session.isSendingChatTTSText && (session.chatTTSUntil || 0) > Date.now()) {
      console.log(`[NativeVoice] user interrupt chatTTS during speaking session=${session.sessionId}`);
      session.isSendingChatTTSText = false;
      session.chatTTSUntil = 0;
      session.currentSpeechText = '';
      clearTimeout(session.chatTTSTimer);
      sendJson(session.client, { type: 'tts_reset', reason: 'user_bargein' });
      if (session.suppressReplyTimer || session.suppressUpstreamUntil) {
        clearUpstreamSuppression(session);
      }
    }
    if (persistUserSpeech(session, rawFinalText || finalText)) {
      session.blockUpstreamAudio = true;
      session.currentTtsType = 'default';
      session.assistantStreamBuffer = '';
      session.assistantStreamReplyId = '';
      sendJson(session.client, { type: 'tts_reset', reason: 'new_turn' });
      processReply(session, finalText).catch((error) => {
        console.error('[NativeVoice] processReply error:', error.message);
      });
    }
    return;
  }

  sendJson(session.client, {
    type: 'event',
    event: message.event,
    payload,
  });
}

function attachClientHandlers(session) {
  session.client.on('message', async (raw, isBinary) => {
    if (isBinary) {
      if (session.upstream && session.upstream.readyState === WebSocket.OPEN && session.upstreamReady) {
        session.upstream.send(createAudioMessage(session.sessionId, raw));
      }
      return;
    }

    let parsed;
    try {
      parsed = JSON.parse(raw.toString('utf8'));
    } catch (error) {
      sendJson(session.client, { type: 'error', error: 'invalid client json' });
      return;
    }

    if (parsed.type === 'start') {
      const assistantProfile = resolveAssistantProfile({
        ...(session.assistantProfile || {}),
        ...((parsed.assistantProfile && typeof parsed.assistantProfile === 'object') ? parsed.assistantProfile : {}),
      });
      session.assistantProfile = assistantProfile;
      session.botName = parsed.botName || assistantProfile.nickname || DEFAULT_VOICE_BOT_NAME;
      session.systemRole = parsed.systemRole || buildVoiceSystemRole(assistantProfile);
      session.speakingStyle = parsed.speakingStyle || session.speakingStyle || DEFAULT_VOICE_SPEAKING_STYLE;
      session.speaker = parsed.speaker || process.env.VOLC_S2S_SPEAKER_ID || 'zh_female_vv_jupiter_bigtts';
      session.modelVersion = parsed.modelVersion || 'O';
      session.greetingText = parsed.greetingText || buildVoiceGreeting(assistantProfile);
      session.userId = parsed.userId || session.userId || null;
      // 立即发送 ready，不等 upstream event 150，大幅缩短前端等待时间
      sendReady(session);
      session.upstream = createUpstreamConnection(session);
      loadHandoffSummaryForVoice(session).catch((error) => {
        console.warn('[NativeVoice] async loadHandoffSummaryForVoice failed:', error.message);
      });
      return;
    }

    if (parsed.type === 'stop') {
      session.client.close();
      return;
    }

    if (parsed.type === 'replay_greeting') {
      replayGreeting(session).catch((error) => {
        console.warn('[NativeVoice] replayGreeting failed:', error.message);
      });
      return;
    }

    if (parsed.type === 'text' && parsed.text) {
      if (persistUserSpeech(session, parsed.text)) {
        processReply(session, parsed.text, session.latestUserTurnSeq).catch((error) => {
          console.error('[NativeVoice] text processReply failed:', error.message);
        });
      }
    }
  });

  session.client.on('close', () => {
    clearTimeout(session.chatTTSTimer);
    clearTimeout(session.greetingTimer);
    clearTimeout(session.greetingAckTimer);
    clearTimeout(session.readyTimer);
    clearTimeout(session.suppressReplyTimer);
    clearTimeout(session.idleTimer);
    if (session.upstream && session.upstream.readyState === WebSocket.OPEN) {
      session.upstream.close();
    }
    sessions.delete(session.sessionId);
  });
}

function createUpstreamConnection(session) {
  const upstream = new WebSocket('wss://openspeech.bytedance.com/api/v3/realtime/dialogue', {
    headers: {
      'X-Api-Resource-Id': 'volc.speech.dialog',
      'X-Api-Access-Key': process.env.VOLC_S2S_TOKEN,
      'X-Api-App-Key': process.env.VOLC_DIALOG_APP_KEY || 'PlgvMymc7f3tQnJ6',
      'X-Api-App-ID': process.env.VOLC_S2S_APP_ID,
      'X-Api-Connect-Id': session.sessionId,
    },
  });

  upstream.on('open', () => {
    upstream.send(createStartConnectionMessage());
    upstream.send(createStartSessionMessage(session.sessionId, buildStartSessionPayload(session)));
  });

  upstream.on('message', (data, isBinary) => {
    if (!isBinary && typeof data === 'string') {
      sendJson(session.client, { type: 'server_text', text: data });
      return;
    }
    handleUpstreamMessage(session, Buffer.isBuffer(data) ? data : Buffer.from(data));
  });

  upstream.on('error', (error) => {
    console.error('[NativeVoice] upstream ws error:', error.message);
    sendJson(session.client, { type: 'error', error: `语音服务连接异常: ${error.message}` });
  });

  upstream.on('close', (code) => {
    console.log(`[NativeVoice] upstream closed session=${session.sessionId} code=${code}`);
    session.upstreamReady = false;
    sendJson(session.client, { type: 'upstream_closed', code });
    setTimeout(() => {
      if (session.client && session.client.readyState === WebSocket.OPEN) {
        session.client.close();
      }
    }, 3000);
  });

  return upstream;
}

function createSession(client, sessionId) {
  const assistantProfile = resolveAssistantProfile();
  const session = {
    sessionId,
    client,
    upstream: null,
    upstreamReady: false,
    isSendingChatTTSText: false,
    latestUserText: '',
    latestUserTurnSeq: 0,
    queuedUserText: '',
    queuedUserTurnSeq: 0,
    processingReply: false,
    blockUpstreamAudio: false,
    directSpeakUntil: 0,
    queuedReplyTimer: null,
    lastPersistedAssistantText: '',
    lastPersistedAssistantAt: 0,
    assistantStreamBuffer: '',
    assistantStreamReplyId: '',
    currentTtsType: '',
    currentSpeechText: '',
    greetingProtectionUntil: 0,
    _echoLogOnce: false,
    _fillerActive: false,
    _pendingExternalRagReply: false,
    _lastPartialAt: 0,
    pendingKbPrequery: null,
    _kbPrequeryText: '',
    _kbPrequeryStartedAt: 0,
    _lastKbTopic: '',
    _lastKbHitAt: 0,
    assistantProfile,
    botName: assistantProfile.nickname,
    systemRole: buildVoiceSystemRole(assistantProfile),
    speakingStyle: DEFAULT_VOICE_SPEAKING_STYLE,
    speaker: process.env.VOLC_S2S_SPEAKER_ID || 'zh_female_vv_jupiter_bigtts',
    modelVersion: 'O',
    greetingText: buildVoiceGreeting(assistantProfile),
    hasSentGreeting: false,
    greetingTimer: null,
    greetingAckTimer: null,
    pendingGreetingAck: false,
    greetingRetryCount: 0,
    readyTimer: null,
    readySent: false,
    handoffSummary: '',
    handoffSummaryUsed: false,
    awaitingUpstreamReply: false,
    pendingAssistantSource: null,
    pendingAssistantToolName: null,
    pendingAssistantMeta: null,
    pendingAssistantTurnSeq: 0,
    lastDeliveredAssistantTurnSeq: 0,
    suppressReplyTimer: null,
    suppressUpstreamUntil: 0,
    idleTimer: null,
    lastActivityAt: Date.now(),
    _lastBargeInResetAt: 0,
    _audioBlockLogOnce: false,
    _lastFinalNormalized: '',
    _lastFinalAt: 0,
  };
  sessions.set(sessionId, session);
  attachClientHandlers(session);
  return session;
}

function setupNativeVoiceGateway(server) {
  const wss = new WebSocketServer({ server, path: '/ws/realtime-dialog' });
  wss.on('connection', async (client, req) => {
    const parsed = url.parse(req.url, true);
    const sessionId = parsed.query?.sessionId;
    if (!sessionId) {
      client.close();
      return;
    }
    const userId = parsed.query?.userId || null;
    const session = createSession(client, sessionId);
    session.userId = userId;
    try {
      await db.createSession(sessionId, userId, 'voice');
    } catch (error) {
      console.warn('[NativeVoice][DB] createSession failed:', error.message);
    }
    sendJson(client, { type: 'connected', sessionId });
  });
  return wss;
}

module.exports = {
  setupNativeVoiceGateway,
};