// Natural turn-taking for chat.bstein.dev using the private Jetsons.
(function(){
  'use strict';

  const modeBtn=document.getElementById('btnVoiceMode');
  const bar=document.getElementById('voiceModeBar');
  const indicator=document.getElementById('voiceModeIndicator');
  const label=document.getElementById('voiceModeLabel');
  const composer=document.getElementById('msg');
  if(!modeBtn||!bar||!indicator||!label||!composer||!navigator.mediaDevices||!window.MediaRecorder) return;

  let ready=false;
  let active=false;
  let state='idle';
  let generation=0;
  let turnSequence=0;
  let recorder=null;
  let stream=null;
  let audioContext=null;
  let captureNode=null;
  let vadTimer=null;
  let responsePollTimer=null;
  let currentAudio=null;
  let playbackSession=null;
  let bargeMonitor=null;
  let bargeCancelPromise=null;
  let suppressAutoRead=false;
  let thinkingCue=null;
  let streamingStt=null;
  let captureTurnId='';
  let thinkingTurnId='';
  let thinkingSession=null;
  let assistantBaseline=null;
  let speechTurn=null;
  let errorTimer=null;
  let visualInputLevel=0;
  let streamingCapability={tts:null,stt:null,preflight:null};
  let voicePreflight=null;
  const voiceTabNonce=(function(){
    try{
      const bytes=new Uint8Array(16);
      window.crypto.getRandomValues(bytes);
      return Array.from(bytes,function(value){return value.toString(16).padStart(2,'0');}).join('');
    }catch(_){return '';}
  })();
  const reducedMotion=window.matchMedia?window.matchMedia('(prefers-reduced-motion: reduce)'):{matches:false};
  const ERROR_VISIBLE_MS=3200;
  const STREAMING_CAPABILITY_URL='/api/voice/streaming/capability';
  const TTS_STREAM_URL='/api/tts/stream';
  const STT_STREAM_PATH='/api/transcribe/stream';
  const VOICE_PREFLIGHT_URL='/api/voice/route-preflight';
  const VOICE_PREFLIGHT_DEBOUNCE_MS=200;
  const VOICE_PREFLIGHT_DEADLINE_MS=1100;
  const VOICE_PREFLIGHT_TIERS=['fast','balanced','deep','maximum'];
  const WORKLET_URL='static/atlas-voice-worklet.js';
  const STT_MAX_QUEUED_BYTES=1048576;
  const STT_MAX_ARCHIVE_BYTES=2880000;
  const BARGE_LOOKBACK_MS=900;
  const BARGE_DUCK_FRAMES=2;
  const BARGE_TRIGGER_FRAMES=4;
  const THINKING_CUE_FIRST_MS=1900;
  const THINKING_CUE_INTERVAL_MS=6500;
  const THINKING_CUE_POOLS={
    en:[{id:'thinking',text:"I'm thinking."},{id:'let_me_think',text:'Let me think.'},{id:'still_working',text:'Still working on that.'},{id:'one_more_moment',text:'One more moment.'}],
    ru:[{id:'thinking',text:'Я думаю.'},{id:'let_me_think',text:'Дайте подумать.'},{id:'still_working',text:'Я всё ещё думаю над этим.'},{id:'one_more_moment',text:'Ещё мгновение.'}],
    es:[{id:'thinking',text:'Estoy pensando.'},{id:'let_me_think',text:'Déjame pensar.'},{id:'still_working',text:'Sigo pensando en eso.'},{id:'one_more_moment',text:'Un momento más.'}],
  };
  const STATE_LABELS={
    listening:'Listening',
    transcribing:'Transcribing…',
    thinking:'Thinking…',
    speaking:'Speaking',
    error:'Voice unavailable',
    idle:'',
  };
  // The only language signal this file trusts is the one the private Whisper
  // service returned for the audio of the turn currently being answered. It is
  // bound to that turn's generation token and consumed exactly once.
  let sttLanguage='';
  let sttLanguageToken=-1;
  const TTS_LANGUAGES=['en','ru','es'];
  const originalAutoRead=window.autoReadLastAssistant;
  const originalApplyPreference=window._applyVoiceModePref;

  function normalizeSttLanguage(value){
    if(typeof value!=='string') return '';
    const code=value.trim().toLowerCase();
    return TTS_LANGUAGES.indexOf(code)>=0?code:'';
  }

  function clearSttLanguage(){
    sttLanguage='';
    sttLanguageToken=-1;
  }

  function rememberSttLanguage(language,token){
    sttLanguage=language||'';
    sttLanguageToken=sttLanguage?token:-1;
  }

  function takeSttLanguage(token){
    const language=sttLanguageToken===token?sttLanguage:'';
    clearSttLanguage();
    return language;
  }

  function toast(message){
    if(typeof window.showToast==='function') window.showToast(message,3000);
  }

  function setState(next,customLabel){
    state=next;
    indicator.className='voice-mode-indicator '+next;
    bar.dataset.voiceState=next;
    bar.setAttribute('aria-busy',next==='transcribing'||next==='thinking'?'true':'false');
    label.textContent=customLabel||STATE_LABELS[next]||'';
    bar.style.display=(active&&next!=='idle')||next==='error'?'':'none';
    resetInputLevel();
  }

  function resetInputLevel(){
    visualInputLevel=0;
    indicator.style.setProperty('--voice-ripple-scale','1.035');
    indicator.style.setProperty('--voice-ripple-opacity','0.3');
  }

  function updateInputLevel(rms){
    if(reducedMotion.matches||state!=='listening') return;
    const target=Math.max(0,Math.min(1,(rms-0.01)/0.18));
    visualInputLevel=(visualInputLevel*0.72)+(target*0.28);
    indicator.style.setProperty('--voice-ripple-scale',(1.035+(visualInputLevel*0.16)).toFixed(3));
    indicator.style.setProperty('--voice-ripple-opacity',(0.26+(visualInputLevel*0.48)).toFixed(3));
  }

  function clearErrorTimer(){
    if(errorTimer){window.clearTimeout(errorTimer);errorTimer=null;}
  }

  function errorMessage(error,fallback){
    return String((error&&error.message)||fallback||'Voice unavailable').trim();
  }

  function createAbortController(){
    const Controller=window.AbortController||(typeof AbortController!=='undefined'?AbortController:null);
    return Controller?new Controller():{signal:undefined,abort:function(){ }};
  }

  function cancelledError(message){
    const error=new Error(message||'Voice turn cancelled');
    error.name='AbortError';
    return error;
  }

  function cancelSpeechTurn(){
    if(!speechTurn) return;
    speechTurn.cancelled=true;
    speechTurn.final=true;
    while(speechTurn.waiters.length) speechTurn.waiters.shift()(null);
    speechTurn=null;
  }

  function cancelStreamingStt(){
    if(!streamingStt) return;
    streamingStt.cancel();
    streamingStt=null;
  }

  function cancelVoicePreflight(turnId){
    const preflight=voicePreflight;
    if(!preflight||(turnId&&preflight.turnId!==turnId)) return;
    voicePreflight=null;
    if(preflight.timer){window.clearTimeout(preflight.timer);preflight.timer=null;}
    if(preflight.deadline){window.clearTimeout(preflight.deadline);preflight.deadline=null;}
    if(preflight.controller){preflight.controller.abort();preflight.controller=null;}
  }

  function scheduleVoicePreflight(turnId,revision,transcript){
    const capability=streamingCapability.preflight;
    const stable=String(transcript||'').replace(/\s+/g,' ').trim();
    if(!capability||!voiceTabNonce||!active||captureTurnId!==turnId||state!=='listening') return;
    if(!Number.isInteger(revision)||revision<1||stable.length<12||stable.length>512) return;
    if(voicePreflight&&voicePreflight.turnId===turnId&&voicePreflight.transcript===stable) return;
    cancelVoicePreflight();
    const preflight={turnId:turnId,revision:revision,transcript:stable,timer:null,deadline:null,controller:null};
    voicePreflight=preflight;
    preflight.timer=window.setTimeout(async function(){
      preflight.timer=null;
      if(voicePreflight!==preflight||!active||captureTurnId!==turnId||state!=='listening') return;
      const controller=createAbortController();
      preflight.controller=controller;
      preflight.deadline=window.setTimeout(function(){controller.abort();},VOICE_PREFLIGHT_DEADLINE_MS);
      try{
        const response=await fetch(VOICE_PREFLIGHT_URL,{
          method:'POST',
          credentials:'same-origin',
          cache:'no-store',
          headers:{'Content-Type':'application/json'},
          body:JSON.stringify({turn_id:turnId,revision:revision,transcript:stable}),
          signal:controller.signal,
        });
        if(!response.ok) return;
        const advisory=await response.json();
        const tier=advisory&&advisory.tier;
        if(
          voicePreflight!==preflight||!active||captureTurnId!==turnId||state!=='listening'||
          advisory.turn_id!==turnId||advisory.revision!==revision||advisory.advisory!==true||
          VOICE_PREFLIGHT_TIERS.indexOf(tier)<0||advisory.target!=='atlas/auto/'+tier
        ) return;
        // This is intentionally feedback-only. The completed transcript still
        // takes the normal Switchyard path and remains the sole routing input.
        const preview=stable.length>60?stable.slice(0,57)+'…':stable;
        label.textContent='Listening · '+preview+' · '+tier;
      }catch(_){
        // A partial can be superseded at any time; advisory failure is silent.
      }finally{
        if(preflight.deadline){window.clearTimeout(preflight.deadline);preflight.deadline=null;}
        preflight.controller=null;
      }
    },VOICE_PREFLIGHT_DEBOUNCE_MS);
  }

  function cancelThinkingCues(){
    const cue=thinkingCue;
    thinkingCue=null;
    if(!cue) return;
    cue.cancelled=true;
    if(cue.timer){window.clearTimeout(cue.timer);cue.timer=null;}
    if(cue.controller){cue.controller.abort();cue.controller=null;}
    if(cue.audioWake){const wake=cue.audioWake;cue.audioWake=null;wake();}
    if(cue.node){try{cue.node.port.postMessage({type:'cancel'});cue.node.disconnect();}catch(_){ }cue.node=null;}
    if(cue.context){try{cue.context.close();}catch(_){ }cue.context=null;}
    cue.gain=null;
    indicator.classList.remove('is-playing');
    indicator.classList.remove('is-ducked');
  }

  function clearBargeCancellation(){
    const cancellation=bargeCancelPromise;
    bargeCancelPromise=null;
    if(cancellation&&cancellation.controller) cancellation.controller.abort();
  }

  function microphoneConstraints(){
    const constraints={echoCancellation:true,noiseSuppression:true,autoGainControl:true};
    const supported=navigator.mediaDevices.getSupportedConstraints?navigator.mediaDevices.getSupportedConstraints():{};
    if(supported.voiceIsolation) constraints.voiceIsolation=true;
    return constraints;
  }

  function acquireMicrophone(){
    return navigator.mediaDevices.getUserMedia({audio:microphoneConstraints()});
  }

  function captureAecIsUsable(capture){
    try{
      const tracks=capture&&capture.getAudioTracks?capture.getAudioTracks():[];
      const settings=tracks.length&&tracks[0].getSettings?tracks[0].getSettings():{};
      return settings.echoCancellation!==false;
    }catch(_){
      return true;
    }
  }

  window._atlasCaptureAecIsUsable=captureAecIsUsable;

  function setPlaybackDucked(ducked){
    const session=playbackSession;
    if(session&&session.gain&&session.context){
      const gain=ducked?0.16:1;
      try{session.gain.gain.setTargetAtTime(gain,session.context.currentTime,0.018);}catch(_){session.gain.gain.value=gain;}
    }
    if(currentAudio) currentAudio.volume=ducked?0.16:1;
    const cue=thinkingCue;
    if(cue&&cue.gain&&cue.context){
      const gain=ducked?0.16:1;
      try{cue.gain.gain.setTargetAtTime(gain,cue.context.currentTime,0.018);}catch(_){cue.gain.gain.value=gain;}
    }
    if(ducked) indicator.classList.add('is-ducked'); else indicator.classList.remove('is-ducked');
  }

  function disposeBargeResources(monitor,keepCapture){
    if(!monitor) return;
    monitor.cancelled=true;
    if(monitor.timer){window.clearInterval(monitor.timer);monitor.timer=null;}
    try{if(monitor.node) monitor.node.disconnect();}catch(_){ }
    try{if(monitor.source) monitor.source.disconnect();}catch(_){ }
    try{if(monitor.silentGain) monitor.silentGain.disconnect();}catch(_){ }
    if(!keepCapture){
      if(monitor.stream) monitor.stream.getTracks().forEach(function(track){track.stop();});
      if(monitor.context){try{monitor.context.close();}catch(_){ }}
    }
    if(!keepCapture) setPlaybackDucked(false);
  }

  function stopBargeMonitor(){
    const monitor=bargeMonitor;
    bargeMonitor=null;
    disposeBargeResources(monitor,false);
  }

  function showUnavailable(message){
    generation+=1;
    active=false;
    thinkingSession=null;
    thinkingTurnId='';
    suppressAutoRead=false;
    clearBargeCancellation();
    stopResponseObserver();
    cancelThinkingCues();
    cancelSpeechTurn();
    stopCapture();
    stopPlayback();
    modeBtn.classList.remove('active');
    setState('error',message);
    clearErrorTimer();
    errorTimer=window.setTimeout(function(){
      errorTimer=null;
      if(!active&&state==='error'&&indicator.classList.contains('error')) setState('idle');
    },ERROR_VISIBLE_MS);
  }

  function stopCapture(){
    cancelVoicePreflight(captureTurnId);
    stopBargeMonitor();
    if(vadTimer){clearInterval(vadTimer);vadTimer=null;}
    if(recorder&&recorder.state!=='inactive'){
      try{recorder.stop();}catch(_){ }
    }
    recorder=null;
    captureNode=null;
    cancelStreamingStt();
    if(stream){stream.getTracks().forEach(function(track){track.stop();});stream=null;}
    if(audioContext){try{audioContext.close();}catch(_){ }audioContext=null;}
  }

  function stopPlayback(){
    if(currentAudio){
      try{currentAudio.pause();currentAudio.currentTime=0;}catch(_){ }
      currentAudio=null;
    }
    if(playbackSession){
      playbackSession.cancelled=true;
      if(playbackSession.blobWake){playbackSession.blobWake();playbackSession.blobWake=null;}
      playbackSession.controllers.forEach(function(controller){controller.abort();});
      if(playbackSession.lowWaterWake){
        playbackSession.lowWaterWake();
        playbackSession.lowWaterWake=null;
      }
      if(playbackSession.drainWake){playbackSession.drainWake();playbackSession.drainWake=null;}
      if(playbackSession.node){
        try{playbackSession.node.port.postMessage({type:'cancel'});playbackSession.node.disconnect();}catch(_){ }
      }
      if(playbackSession.context){try{playbackSession.context.close();}catch(_){ }}
      playbackSession=null;
    }
    indicator.classList.remove('is-playing');
    indicator.classList.remove('is-ducked');
  }

  function stopResponseObserver(){
    if(responsePollTimer){clearInterval(responsePollTimer);responsePollTimer=null;}
  }

  function deactivate(showMessage){
    generation+=1;
    active=false;
    thinkingSession=null;
    thinkingTurnId='';
    clearErrorTimer();
    clearSttLanguage();
    suppressAutoRead=false;
    clearBargeCancellation();
    stopResponseObserver();
    cancelThinkingCues();
    cancelSpeechTurn();
    stopCapture();
    stopPlayback();
    modeBtn.classList.remove('active');
    setState('idle');
    if(showMessage) toast('Hands-free voice mode off');
  }

  function restartSoon(token,delay){
    window.setTimeout(function(){
      if(active&&token===generation) startListening(token);
    },delay||500);
  }

  function assistantRows(){
    return document.querySelectorAll('.msg-row[data-role="assistant"], .assistant-segment[data-raw-text]');
  }

  function readAssistantRow(row){
    if(!row) return '';
    if(row.dataset&&typeof row.dataset.rawText==='string') return row.dataset.rawText;
    return typeof row.textContent==='string'?row.textContent:'';
  }

  function rememberAssistantBaseline(){
    const rows=assistantRows();
    const row=rows.length?rows[rows.length-1]:null;
    assistantBaseline={row:row,text:readAssistantRow(row),count:rows.length};
  }

  async function settleBargeCancellation(token){
    const cancellation=bargeCancelPromise;
    if(!cancellation) return true;
    try{await cancellation.promise;}catch(_){ }
    const deadline=Date.now()+10000;
    while(active&&token===generation&&Date.now()<deadline){
      const sessionId=(typeof S!=='undefined'&&S.session)?S.session.session_id:'';
      const activeStreamId=typeof S!=='undefined'?String(S.activeStreamId||''):'';
      const busy=typeof S!=='undefined'&&!!S.busy;
      if(sessionId!==cancellation.sessionId) break;
      if(!busy&&(!cancellation.streamId||activeStreamId!==cancellation.streamId)){
        if(bargeCancelPromise===cancellation) bargeCancelPromise=null;
        return true;
      }
      await new Promise(function(resolve){window.setTimeout(resolve,50);});
    }
    if(bargeCancelPromise===cancellation) bargeCancelPromise=null;
    return false;
  }

  async function sendTranscript(transcript,token,language){
    if(!active||token!==generation) return;
    cancelVoicePreflight(captureTurnId);
    const text=String(transcript||'').trim();
    if(!text){clearSttLanguage();restartSoon(token,350);return;}
    composer.value=text;
    if(typeof window.autoResize==='function') window.autoResize();
    setState('thinking');
    startBargeMonitor(token);
    if(!bargeCancelPromise&&typeof S!=='undefined'&&(S.busy||S.activeStreamId)){
      suppressAutoRead=true;
      bargeCancelPromise=cancelActiveModelTurn();
    }
    const cancellationSettled=await settleBargeCancellation(token);
    if(!active||token!==generation) return;
    if(!cancellationSettled){
      toast('The previous response did not stop. Please repeat your interruption.');
      restartSoon(token,250);
      return;
    }
    thinkingSession=(typeof S!=='undefined'&&S.session)?S.session.session_id:null;
    thinkingTurnId=captureTurnId||String(token)+'-'+String(++turnSequence);
    rememberAssistantBaseline();
    rememberSttLanguage(language,token);
    if(typeof window.send==='function'){
      window.send();
      suppressAutoRead=false;
      startResponseObserver(token);
      scheduleThinkingCues(token,language,thinkingTurnId);
    }
  }

  function audioExtension(mimeType){
    const normalized=String(mimeType||'').toLowerCase();
    if(normalized.indexOf('wav')>=0) return 'wav';
    if(normalized.indexOf('ogg')>=0) return 'ogg';
    if(normalized.indexOf('mp4')>=0) return 'mp4';
    return 'webm';
  }

  async function transcribe(blob,token){
    if(!active||token!==generation) return;
    setState('transcribing');
    const ext=audioExtension(blob.type);
    const form=new FormData();
    form.append('file',new File([blob],'voice-input.'+ext,{type:blob.type||'audio/'+ext}));
    try{
      const response=await fetch('/api/transcribe',{method:'POST',body:form});
      const payload=await response.json().catch(function(){return {};});
      if(!response.ok) throw new Error(payload.error||('Whisper request failed: '+response.status));
      sendTranscript(payload.transcript,token,normalizeSttLanguage(payload.language));
    }catch(error){
      if(!active||token!==generation) return;
      const message=errorMessage(error,'Private Whisper is unavailable');
      showUnavailable(message);
      toast(message);
      // If the browser supplies its own recognizer, hand control back to the
      // upstream voice implementation until the Jetson becomes healthy again.
      if(window.SpeechRecognition||window.webkitSpeechRecognition){
        modeBtn.removeEventListener('click',onVoiceClick,true);
        window.setTimeout(function(){modeBtn.click();},50);
      }
    }
  }

  function websocketUrl(path){
    const protocol=window.location&&window.location.protocol==='https:'?'wss:':'ws:';
    return protocol+'//'+window.location.host+path;
  }

  function encodePcm16(samples){
    const bytes=new ArrayBuffer(samples.length*2);
    const view=new DataView(bytes);
    for(let index=0;index<samples.length;index+=1){
      const value=Math.max(-1,Math.min(1,samples[index]));
      view.setInt16(index*2,value<0?value*32768:value*32767,true);
    }
    return bytes;
  }

  function pcm16WavBlob(buffers,sampleRate){
    const chunks=Array.isArray(buffers)?buffers:[];
    const pcmBytes=chunks.reduce(function(total,chunk){return total+(chunk?chunk.byteLength:0);},0);
    const wav=new ArrayBuffer(44+pcmBytes);
    const view=new DataView(wav);
    const write=function(offset,value){for(let index=0;index<value.length;index+=1)view.setUint8(offset+index,value.charCodeAt(index));};
    write(0,'RIFF');
    view.setUint32(4,36+pcmBytes,true);
    write(8,'WAVE');
    write(12,'fmt ');
    view.setUint32(16,16,true);
    view.setUint16(20,1,true);
    view.setUint16(22,1,true);
    view.setUint32(24,sampleRate,true);
    view.setUint32(28,sampleRate*2,true);
    view.setUint16(32,2,true);
    view.setUint16(34,16,true);
    write(36,'data');
    view.setUint32(40,pcmBytes,true);
    const output=new Uint8Array(wav,44);
    let offset=0;
    chunks.forEach(function(chunk){const bytes=new Uint8Array(chunk);output.set(bytes,offset);offset+=bytes.length;});
    return new Blob([wav],{type:'audio/wav'});
  }

  window._atlasPcm16WavBlob=pcm16WavBlob;

  function createResampler(sourceRate,targetRate){
    let tail=null;
    let position=0;
    const ratio=sourceRate/targetRate;
    return function(samples){
      const input=new Float32Array(samples.length+(tail===null?0:1));
      let offset=0;
      if(tail!==null){input[0]=tail;offset=1;}
      input.set(samples,offset);
      if(input.length<2){tail=input.length?input[0]:tail;return new Float32Array(0);}
      const output=[];
      while(position<input.length-1){
        const left=Math.floor(position);
        const fraction=position-left;
        output.push(input[left]+((input[left+1]-input[left])*fraction));
        position+=ratio;
      }
      position-=input.length-1;
      tail=input[input.length-1];
      return new Float32Array(output);
    };
  }

  function createStreamingSttSession(turnId,context){
    if(!streamingCapability.stt||!window.WebSocket||!window.location) return null;
    let socket;
    let settled=false;
    let committed=false;
    let speculative=false;
    let workletReady=false;
    let partialRevision=-1;
    let lastPreflightText='';
    let queue=[];
    let queuedBytes=0;
    let flushTimer=null;
    let archive=[];
    let archiveBytes=0;
    let cancelled=false;
    let resolveFinal;
    let rejectFinal;
    const finalPromise=new Promise(function(resolve,reject){resolveFinal=resolve;rejectFinal=reject;});
    // A transport can fail before recorder.onstop awaits it. Keep the rejection
    // observed without changing what the later await receives.
    finalPromise.catch(function(){ });
    const resample=createResampler(context.sampleRate,16000);

    function clearFlushTimer(){
      if(flushTimer){window.clearTimeout(flushTimer);flushTimer=null;}
    }
    function clearQueue(){queue=[];queuedBytes=0;clearFlushTimer();}
    function clearArchive(){archive=[];archiveBytes=0;}
    function archivePcm(bytes){
      if(cancelled||!bytes||!bytes.byteLength||archiveBytes>=STT_MAX_ARCHIVE_BYTES) return;
      const retained=Math.min(bytes.byteLength,STT_MAX_ARCHIVE_BYTES-archiveBytes);
      const even=retained-(retained%2);
      if(!even) return;
      archive.push(bytes.slice(0,even));
      archiveBytes+=even;
    }
    function reject(error){
      if(settled) return;
      settled=true;
      cancelVoicePreflight(turnId);
      clearQueue();
      rejectFinal(error instanceof Error?error:new Error(String(error||'Streaming transcription failed')));
    }
    function sendJson(payload){
      if(socket&&socket.readyState===1){socket.send(JSON.stringify(payload));return true;}
      return false;
    }
    function scheduleFlush(){
      if(flushTimer||settled||!queue.length||!socket||socket.readyState!==1) return;
      flushTimer=window.setTimeout(function(){flushTimer=null;flush();},20);
    }
    function flush(){
      clearFlushTimer();
      if(settled){clearQueue();return;}
      if(!socket||socket.readyState!==1) return;
      while(queue.length&&socket.bufferedAmount<524288){
        const bytes=queue.shift();
        queuedBytes=Math.max(0,queuedBytes-bytes.byteLength);
        socket.send(bytes);
      }
      if(queue.length) scheduleFlush();
    }
    try{
      const csrf=String((window.__HERMES_CONFIG__&&window.__HERMES_CONFIG__.csrfToken)||'');
      const protocols=['hermes-voice-v1'];
      if(csrf) protocols.push('hermes-csrf.'+csrf);
      socket=new WebSocket(websocketUrl(STT_STREAM_PATH),protocols);
      socket.binaryType='arraybuffer';
    }catch(error){
      reject(error);
      return null;
    }
    socket.onopen=function(){
      sendJson({type:'start',turn_id:turnId,format:'pcm_s16le',sample_rate:16000,language:'auto'});
      flush();
    };
    socket.onmessage=function(event){
      if(typeof event.data!=='string') return;
      let payload;
      try{payload=JSON.parse(event.data);}catch(_){return;}
      if(payload.turn_id!==turnId) return;
      if(payload.type==='partial'&&payload.rolling===true){
        const revision=Number(payload.revision);
        if(Number.isFinite(revision)&&revision>partialRevision){
          partialRevision=revision;
          const stable=String(payload.stable_transcript||'').trim();
          const provisional=String(payload.transcript||'').trim();
          const visible=stable||provisional;
          if(visible&&active&&captureTurnId===turnId&&state==='listening'){
            const preview=visible.length>72?visible.slice(0,69)+'…':visible;
            label.textContent='Listening · '+preview+(stable?'':' · provisional');
            if(stable!==lastPreflightText){
              if(stable){
                lastPreflightText=stable;
                scheduleVoicePreflight(turnId,revision,stable);
              }
            }
          }
        }
      }else if(payload.type==='final'&&!settled){
        settled=true;
        cancelVoicePreflight(turnId);
        clearQueue();
        clearArchive();
        resolveFinal({transcript:payload.transcript||'',language:normalizeSttLanguage(payload.language)});
      }else if(payload.type==='error'){
        reject(new Error(payload.error||'Streaming transcription failed'));
      }
    };
    socket.onerror=function(){reject(new Error('Streaming transcription connection failed'));};
    socket.onclose=function(){if(!settled) reject(new Error('Streaming transcription closed before final result'));};

    return {
      finalPromise:finalPromise,
      setWorkletReady:function(value){workletReady=value;},
      push:function(samples){
        if(cancelled||committed||!workletReady) return;
        const pcm=resample(samples);
        if(!pcm.length) return;
        const bytes=encodePcm16(pcm);
        archivePcm(bytes);
        if(settled) return;
        if(queuedBytes+bytes.byteLength>STT_MAX_QUEUED_BYTES){
          reject(new Error('Streaming transcription backpressure limit exceeded'));
          if(socket&&socket.readyState<2) socket.close(1008,'client backpressure');
          return;
        }
        queue.push(bytes);
        queuedBytes+=bytes.byteLength;
        flush();
      },
      takeFallbackBlob:function(){
        if(!archiveBytes) return null;
        const blob=pcm16WavBlob(archive,16000);
        clearArchive();
        return blob;
      },
      speculate:function(){
        if(settled||committed||speculative) return;
        speculative=true;
        sendJson({type:'speculate',turn_id:turnId});
      },
      resume:function(){
        if(settled||committed||!speculative) return;
        speculative=false;
        sendJson({type:'resume',turn_id:turnId});
      },
      commit:function(){
        if(settled||committed) return finalPromise;
        committed=true;
        flush();
        const commitDeadline=Date.now()+30000;
        const sendCommit=function(){
          if(settled) return;
          if(!socket||socket.readyState>1||Date.now()>=commitDeadline){
            reject(new Error('Streaming transcription closed before commit'));
            return;
          }
          if(socket.readyState!==1||queue.length){flush();window.setTimeout(sendCommit,20);return;}
          if(!sendJson({type:'commit',turn_id:turnId})) reject(new Error('Streaming transcription commit failed'));
        };
        sendCommit();
        return finalPromise;
      },
      cancel:function(){
        cancelled=true;
        cancelVoicePreflight(turnId);
        clearQueue();
        clearArchive();
        if(!settled){sendJson({type:'cancel',turn_id:turnId});reject(new Error('Streaming transcription cancelled'));}
        if(socket&&socket.readyState<2) socket.close(1000,'cancelled');
      },
    };
  }

  async function installCaptureWorklet(context,source,session){
    if(!session) return false;
    if(!context.audioWorklet||!window.AudioWorkletNode){
      session.cancel();
      if(streamingStt===session) streamingStt=null;
      return false;
    }
    try{
      await context.audioWorklet.addModule(WORKLET_URL);
      if(!streamingStt||streamingStt!==session) return false;
      const node=new AudioWorkletNode(context,'atlas-pcm-capture');
      const silentGain=context.createGain();
      silentGain.gain.value=0;
      let flushResolve=null;
      node.port.onmessage=function(event){
        if(!event.data) return;
        if(event.data.type==='flushed'&&flushResolve){flushResolve();flushResolve=null;return;}
        if(!streamingStt||streamingStt!==session||event.data.type!=='pcm') return;
        session.push(new Float32Array(event.data.samples));
      };
      node._atlasFlush=function(){
        return new Promise(function(resolve){flushResolve=resolve;node.port.postMessage({type:'flush'});});
      };
      source.connect(node);
      node.connect(silentGain);
      silentGain.connect(context.destination);
      captureNode=node;
      session.setWorkletReady(true);
      return true;
    }catch(_){
      session.cancel();
      if(streamingStt===session) streamingStt=null;
      return false;
    }
  }

  function cancelActiveModelTurn(){
    const sessionId=(typeof S!=='undefined'&&S.session)?String(S.session.session_id||''):'';
    const streamId=typeof S!=='undefined'?String(S.activeStreamId||''):'';
    if(!streamId) return {sessionId:sessionId,streamId:'',controller:null,promise:Promise.resolve(false)};
    const controller=createAbortController();
    const timer=window.setTimeout(function(){controller.abort();},1800);
    const promise=(async function(){
      try{
        const url=new URL('api/chat/cancel?stream_id='+encodeURIComponent(streamId),document.baseURI||location.href).href;
        const response=await fetch(url,{credentials:'include',signal:controller.signal});
        let payload=null;
        try{payload=await response.json();}catch(_){ }
        const currentSession=(typeof S!=='undefined'&&S.session)?String(S.session.session_id||''):'';
        if(response.ok&&payload&&payload.cancelled===false&&currentSession===sessionId&&String(S.activeStreamId||'')===streamId){
          S.activeStreamId=null;
          if(S.session) S.session.active_stream_id=null;
          if(typeof setBusy==='function') setBusy(false); else S.busy=false;
        }
        return !!response.ok;
      }catch(_){
        return false;
      }finally{
        window.clearTimeout(timer);
      }
    })();
    return {sessionId:sessionId,streamId:streamId,controller:controller,promise:promise};
  }

  function trimBargeLookback(monitor){
    const maximum=Math.max(1,Math.round(monitor.context.sampleRate*BARGE_LOOKBACK_MS/1000));
    while(monitor.lookbackFrames>maximum&&monitor.lookback.length){
      const overflow=monitor.lookbackFrames-maximum;
      const first=monitor.lookback[0];
      if(first.length<=overflow){monitor.lookback.shift();monitor.lookbackFrames-=first.length;continue;}
      monitor.lookback[0]=first.slice(overflow);
      monitor.lookbackFrames-=overflow;
    }
  }

  async function triggerBargeIn(monitor){
    if(!bargeMonitor||bargeMonitor!==monitor||monitor.cancelled||!active||monitor.token!==generation) return;
    bargeMonitor=null;
    if(monitor.timer){window.clearInterval(monitor.timer);monitor.timer=null;}
    // Keep the old capture worklet alive until the new STT worklet is attached.
    // Its lookback becomes an untrimmed handoff buffer so no syllables disappear
    // during AudioWorklet/session setup.
    monitor.handoff=true;
    const oldToken=monitor.token;
    generation+=1;
    const token=generation;
    thinkingSession=null;
    thinkingTurnId='';
    suppressAutoRead=true;
    clearSttLanguage();
    stopResponseObserver();
    cancelThinkingCues();
    cancelSpeechTurn();
    stopPlayback();
    if(typeof window.stopTTS==='function') window.stopTTS();
    clearBargeCancellation();
    bargeCancelPromise=cancelActiveModelTurn();
    setState('listening','Listening — interrupted');
    if(oldToken===token) return;
    startListening(token,{
      stream:monitor.stream,
      context:monitor.context,
      lookback:monitor.lookback,
      handoffMonitor:monitor,
      heardSpeech:true,
      requireStreamingLookback:true,
    });
  }

  async function startBargeMonitor(token){
    if(!active||token!==generation||(state!=='thinking'&&state!=='speaking')||bargeMonitor) return;
    const monitor={token:token,cancelled:false,handoff:false,aecUsable:true,timer:null,stream:null,context:null,source:null,node:null,silentGain:null,lookback:[],lookbackFrames:0};
    bargeMonitor=monitor;
    try{
      monitor.stream=await acquireMicrophone();
      if(!active||token!==generation||bargeMonitor!==monitor){disposeBargeResources(monitor,false);return;}
      monitor.aecUsable=captureAecIsUsable(monitor.stream);
      const Context=window.AudioContext||window.webkitAudioContext;
      try{monitor.context=new Context({latencyHint:'interactive'});}catch(_){monitor.context=new Context();}
      const analyser=monitor.context.createAnalyser();
      analyser.fftSize=1024;
      monitor.source=monitor.context.createMediaStreamSource(monitor.stream);
      monitor.source.connect(analyser);
      if(monitor.context.audioWorklet&&window.AudioWorkletNode){
        await monitor.context.audioWorklet.addModule(WORKLET_URL);
        if(bargeMonitor!==monitor||monitor.cancelled){disposeBargeResources(monitor,false);return;}
        monitor.node=new AudioWorkletNode(monitor.context,'atlas-pcm-capture');
        monitor.silentGain=monitor.context.createGain();
        monitor.silentGain.gain.value=0;
        monitor.node.port.onmessage=function(event){
          if(monitor.cancelled||(!monitor.handoff&&bargeMonitor!==monitor)||!event.data||event.data.type!=='pcm') return;
          const samples=new Float32Array(event.data.samples);
          monitor.lookback.push(samples);
          monitor.lookbackFrames+=samples.length;
          if(!monitor.handoff) trimBargeLookback(monitor);
        };
        monitor.source.connect(monitor.node);
        monitor.node.connect(monitor.silentGain);
        monitor.silentGain.connect(monitor.context.destination);
      }
      await monitor.context.resume();
      const samples=new Uint8Array(analyser.fftSize);
      let noiseFloor=0.008;
      let voiceFrames=0;
      let ducked=false;
      let speechArmAt=Date.now()+100;
      let playbackWasActive=false;
      monitor.timer=window.setInterval(function(){
        if(!active||token!==generation||bargeMonitor!==monitor||(state!=='thinking'&&state!=='speaking')){stopBargeMonitor();return;}
        analyser.getByteTimeDomainData(samples);
        let energy=0;
        for(let index=0;index<samples.length;index+=1){const value=(samples[index]-128)/128;energy+=value*value;}
        const rms=Math.sqrt(energy/samples.length);
        const now=Date.now();
        const playbackActive=indicator.classList.contains('is-playing')||!!currentAudio||!!(playbackSession&&playbackSession.node)||!!(thinkingCue&&thinkingCue.node);
        if(playbackActive&&!playbackWasActive){
          // AEC needs a brief convergence window when local speech starts. PCM
          // lookback preserves a real interruption spoken during this guard.
          // A brief cached thinking cue uses the shorter guard so an "um" can
          // still interrupt it; answer playback gets the conservative window.
          speechArmAt=now+(state==='thinking'?150:450);
          voiceFrames=0;
          if(ducked){ducked=false;setPlaybackDucked(false);}
        }else if(!playbackActive&&playbackWasActive){
          speechArmAt=now+100;
        }
        playbackWasActive=playbackActive;
        const threshold=Math.max(0.05,(noiseFloor*3)+0.008);
        // Never treat speaker leakage as an interruption when the browser says
        // the requested AEC was not applied. Quiet Thinking remains fully
        // interruptible, and unknown/unsupported settings preserve normal use.
        const automaticBargeAllowed=!playbackActive||monitor.aecUsable;
        const voiceNow=automaticBargeAllowed&&now>=speechArmAt&&rms>threshold;
        if(!voiceNow) noiseFloor=(noiseFloor*0.975)+(Math.min(rms,threshold)*0.025);
        voiceFrames=voiceNow?Math.min(voiceFrames+1,BARGE_TRIGGER_FRAMES):Math.max(voiceFrames-1,0);
        if(voiceFrames>=BARGE_DUCK_FRAMES&&!ducked){ducked=true;setPlaybackDucked(true);}
        if(!voiceFrames&&ducked){ducked=false;setPlaybackDucked(false);}
        if(voiceFrames>=BARGE_TRIGGER_FRAMES) triggerBargeIn(monitor);
      },50);
    }catch(_){
      if(bargeMonitor===monitor) bargeMonitor=null;
      disposeBargeResources(monitor,false);
      // Barge-in is an optional full-duplex enhancement. The normal finalized
      // microphone turn remains available if the browser rejects concurrent
      // capture or AudioWorklet initialization.
    }
  }

  async function transcribeStreamingOrFallback(blob,token,session,allowContainerFallback){
    if(!active||token!==generation) return;
    setState('transcribing');
    let pcmFallback=null;
    if(session){
      try{
        const result=await session.commit();
        if(!String(result.transcript||'').trim()) throw new Error('Streaming transcription returned no final text');
        if(active&&token===generation){
          streamingStt=null;
          sendTranscript(result.transcript,token,result.language);
          return;
        }
      }catch(_){
        // The finalized browser container below is the quality-preserving path
        // whenever rolling PCM transport or speculative inference fails.
        if(typeof session.takeFallbackBlob==='function') pcmFallback=session.takeFallbackBlob();
      }
      if(streamingStt===session) streamingStt=null;
    }
    if(pcmFallback){
      transcribe(pcmFallback,token);
      return;
    }
    if(allowContainerFallback===false){
      toast('I missed the start of that interruption. Please repeat it.');
      restartSoon(token,250);
      return;
    }
    transcribe(blob,token);
  }

  async function startListening(token,reusedCapture){
    if(!active||token!==generation) return;
    stopCapture();
    stopPlayback();
    cancelSpeechTurn();
    clearSttLanguage();
    captureTurnId=(voiceTabNonce?voiceTabNonce+'-':'')+String(token)+'-'+String(++turnSequence);
    setState('listening');
    try{
      const capture=reusedCapture&&reusedCapture.stream?reusedCapture.stream:await acquireMicrophone();
      if(!active||token!==generation){
        if(reusedCapture&&reusedCapture.handoffMonitor) disposeBargeResources(reusedCapture.handoffMonitor,false);
        else capture.getTracks().forEach(function(track){track.stop();});
        return;
      }
      stream=capture;
      const Context=window.AudioContext||window.webkitAudioContext;
      if(reusedCapture&&reusedCapture.context){
        audioContext=reusedCapture.context;
      }else{
        try{
          // Let the browser's native resampler produce Whisper's 16 kHz input.
          audioContext=new Context({sampleRate:16000,latencyHint:'interactive'});
        }catch(_){
          audioContext=new Context();
        }
      }
      const analyser=audioContext.createAnalyser();
      analyser.fftSize=2048;
      const highpass=audioContext.createBiquadFilter();
      highpass.type='highpass';
      highpass.frequency.value=140;
      highpass.Q.value=0.7;
      const mediaSource=audioContext.createMediaStreamSource(stream);
      mediaSource.connect(highpass);
      highpass.connect(analyser);
      streamingStt=createStreamingSttSession(captureTurnId,audioContext);
      // Whisper receives the browser's full-band processed microphone signal;
      // the 140 Hz high-pass remains a VAD-only aid so low voices are not
      // needlessly altered before final recognition.
      if(streamingStt) await installCaptureWorklet(audioContext,mediaSource,streamingStt);
      if(streamingStt&&reusedCapture&&Array.isArray(reusedCapture.lookback)){
        reusedCapture.lookback.forEach(function(samples){streamingStt.push(samples);});
      }
      if(reusedCapture&&reusedCapture.handoffMonitor){
        disposeBargeResources(reusedCapture.handoffMonitor,true);
        reusedCapture.handoffMonitor=null;
      }
      if(reusedCapture&&reusedCapture.requireStreamingLookback&&!streamingStt){
        toast('Streaming transcription is unavailable. Please repeat your interruption.');
        stopCapture();
        restartSoon(token,250);
        return;
      }
      const samples=new Uint8Array(analyser.fftSize);
      const mimeTypes=['audio/webm;codecs=opus','audio/ogg;codecs=opus','audio/mp4;codecs=mp4a.40.2','audio/mp4','audio/webm'];
      const mime=mimeTypes.find(function(value){return MediaRecorder.isTypeSupported(value);})||'';
      const chunks=[];
      let heardSpeech=!!(reusedCapture&&reusedCapture.heardSpeech);
      let voiceFrames=heardSpeech?3:0;
      let noiseFloor=0.008;
      let lastSpeech=Date.now();
      let speculative=false;
      const started=Date.now();
      recorder=new MediaRecorder(stream,mime?{mimeType:mime}:undefined);
      let recordedMime=recorder.mimeType||mime||'';
      recorder.ondataavailable=function(event){
        if(!event.data||!event.data.size) return;
        if(event.data.type) recordedMime=event.data.type;
        chunks.push(event.data);
      };
      recorder.onstop=async function(){
        if(vadTimer){clearInterval(vadTimer);vadTimer=null;}
        const finalCaptureNode=captureNode;
        if(finalCaptureNode&&typeof finalCaptureNode._atlasFlush==='function'){
          await Promise.race([
            finalCaptureNode._atlasFlush(),
            new Promise(function(resolve){window.setTimeout(resolve,100);}),
          ]);
        }
        const recordedStream=stream;
        stream=null;
        if(recordedStream) recordedStream.getTracks().forEach(function(track){track.stop();});
        const context=audioContext;
        audioContext=null;
        if(context){try{context.close();}catch(_){ }}
        captureNode=null;
        recorder=null;
        if(!active||token!==generation){cancelStreamingStt();return;}
        if(!heardSpeech||!chunks.length){cancelStreamingStt();restartSoon(token,300);return;}
        const session=streamingStt;
        transcribeStreamingOrFallback(
          new Blob(chunks,{type:recordedMime||'audio/webm'}),
          token,
          session,
          !(reusedCapture&&reusedCapture.requireStreamingLookback)
        );
      };
      // Ask the browser for one finalized container at stop. Android Chromium
      // can emit timeslice fragments without a reusable EBML initialization
      // header; concatenating those fragments made otherwise valid recordings
      // intermittently unreadable by ffmpeg. A bounded 90-second Opus capture
      // is small enough to retain as one browser-owned recording.
      recorder.start();
      const silenceMs=Math.max(900,parseInt(localStorage.getItem('hermes-voice-silence-ms')||'1100',10)||1100);
      const speculateMs=Math.min(silenceMs-250,Math.max(450,Math.round(silenceMs*0.55)));
      vadTimer=window.setInterval(function(){
        if(!active||token!==generation||!recorder||recorder.state==='inactive') return;
        analyser.getByteTimeDomainData(samples);
        let energy=0;
        for(let index=0;index<samples.length;index+=1){
          const normalized=(samples[index]-128)/128;
          energy+=normalized*normalized;
        }
        const rms=Math.sqrt(energy/samples.length);
        updateInputLevel(rms);
        const now=Date.now();
        const speechThreshold=Math.max(0.04,noiseFloor*2.4+0.006);
        const voiceNow=rms>speechThreshold;
        if(!heardSpeech&&!voiceNow){noiseFloor=(noiseFloor*0.94)+(rms*0.06);}
        voiceFrames=voiceNow?Math.min(voiceFrames+1,5):Math.max(voiceFrames-1,0);
        if(!heardSpeech&&voiceFrames>=3){
          heardSpeech=true;
          lastSpeech=now;
        }else if(heardSpeech&&voiceNow){
          lastSpeech=now;
          if(speculative&&streamingStt){streamingStt.resume();speculative=false;}
        }
        if(heardSpeech&&!voiceNow&&!speculative&&(now-lastSpeech)>=speculateMs&&streamingStt){
          streamingStt.speculate();
          speculative=true;
        }
        const finished=heardSpeech&&(now-lastSpeech)>=silenceMs;
        const timedOut=now-started>=90000;
        const idle=(!heardSpeech)&&(now-started)>=20000;
        if(finished||timedOut||idle){
          if(vadTimer){clearInterval(vadTimer);vadTimer=null;}
          try{recorder.stop();}catch(_){ }
        }
      },100);
    }catch(error){
      if(reusedCapture&&reusedCapture.handoffMonitor){
        disposeBargeResources(reusedCapture.handoffMonitor,true);
        reusedCapture.handoffMonitor=null;
      }
      if(!active||token!==generation) return;
      const message=errorMessage(error,'Microphone permission is required');
      showUnavailable(message);
      toast(message);
    }
  }

  function stripHttpUrlsForSpeech(text){
    return String(text||'').replace(/(^|\s+[([{]|\s+|[([{"'])https?:\/\/[^\s<>"']+/gi,function(match,prefix){
      let address=match.slice(prefix.length);
      let suffix='';
      while(address){
        const last=address.slice(-1);
        let trailing=/[.,!?;:…，。！？；：]/.test(last);
        if(last===')') trailing=(address.match(/\)/g)||[]).length>(address.match(/\(/g)||[]).length;
        if(last===']') trailing=(address.match(/\]/g)||[]).length>(address.match(/\[/g)||[]).length;
        if(last==='}') trailing=(address.match(/\}/g)||[]).length>(address.match(/\{/g)||[]).length;
        if(!trailing) break;
        suffix=last+suffix;
        address=address.slice(0,-1);
      }
      const pairs={'(':')','[':']','{':'}'};
      const opening=prefix.slice(-1);
      if(pairs[opening]&&suffix.startsWith(pairs[opening])){
        prefix=prefix.slice(0,-1);
        suffix=suffix.slice(1);
      }
      if(/^\s+$/.test(prefix)&&/^[.,!?;:…，。！？；：]/.test(suffix)) prefix='';
      return prefix+suffix;
    });
  }

  window._atlasStripHttpUrlsForSpeech=stripHttpUrlsForSpeech;

  function cleanForSpeech(text){
    const cleaned=typeof window._stripForTTS==='function'?window._stripForTTS(text):String(text||'').replace(/```[\s\S]*?```/g,' code block ');
    return stripHttpUrlsForSpeech(cleaned).replace(/\s+/g,' ').trim();
  }

  function sentenceEnd(text){
    const source=String(text||'');
    const boundary=/[.!?…]+["')\]}]*(?:\s|$)/g;
    const abbreviation=/(?:\b(?:mr|mrs|ms|dr|prof|sr|jr|st|vs|etc|e\.g|i\.e)|\b[A-Z])\.$/i;
    let match;
    while((match=boundary.exec(source))){
      const end=match.index+match[0].trimEnd().length;
      const prefix=source.slice(0,end).replace(/["')\]}]+$/,'');
      if(prefix.endsWith('.')&&abbreviation.test(prefix)) continue;
      return end;
    }
    return -1;
  }

  function preferredCut(text,min,target,max){
    const bounded=text.slice(0,max);
    const candidates=[];
    const punctuation=/[,;:—–.!?…]+["')\]}]*(?:\s|$)/g;
    let match;
    while((match=punctuation.exec(bounded))){
      const end=match.index+match[0].trimEnd().length;
      if(end>=min) candidates.push({end:end,weight:Math.abs(end-target)});
    }
    if(candidates.length){
      candidates.sort(function(left,right){return left.weight-right.weight;});
      return candidates[0].end;
    }
    const spaces=[];
    const whitespace=/\s+/g;
    while((match=whitespace.exec(bounded))){if(match.index>=min) spaces.push(match.index);}
    if(spaces.length){
      spaces.sort(function(left,right){return Math.abs(left-target)-Math.abs(right-target);});
      return spaces[0];
    }
    return Math.min(max,text.length);
  }

  function adaptiveChunks(text,final,firstChunk){
    const source=String(text||'').trim();
    if(!source) return {chunks:[],consumed:0};
    const chunks=[];
    let offset=0;
    if(firstChunk!==false){
      const firstSentence=sentenceEnd(source);
      if(firstSentence<0&&!final) return {chunks:[],consumed:0};
      const firstAvailable=firstSentence>=0?firstSentence:source.length;
      const firstSlice=source.slice(0,firstAvailable);
      const firstCut=firstSlice.length<=60?firstSlice.length:preferredCut(firstSlice,40,52,60);
      chunks.push(source.slice(0,firstCut).trim());
      offset=firstCut;
    }
    while(offset<source.length){
      const remaining=source.slice(offset).trimStart();
      offset=source.length-remaining.length;
      if(!remaining) break;
      if(remaining.length<100){
        const complete=sentenceEnd(remaining);
        if(!final&&complete<0) break;
        const end=final?remaining.length:complete;
        chunks.push(remaining.slice(0,end).trim());
        offset+=end;
        continue;
      }
      const cut=preferredCut(remaining,100,120,140);
      if(!final&&cut===remaining.length&&remaining.length<140) break;
      chunks.push(remaining.slice(0,cut).trim());
      offset+=cut;
    }
    return {chunks:chunks.filter(Boolean),consumed:offset};
  }

  // Export the deterministic splitter as a narrow diagnostic/test seam.
  window._atlasAdaptiveChunks=function(text,final){return adaptiveChunks(text,final!==false,true).chunks;};

  function playBlob(blob,token){
    return new Promise(function(resolve,reject){
      if(!active||token!==generation){resolve();return;}
      const session=playbackSession;
      const url=URL.createObjectURL(blob);
      const audio=new Audio(url);
      currentAudio=audio;
      let settled=false;
      function cleanup(callback,value){
        if(settled) return;
        settled=true;
        if(currentAudio===audio) currentAudio=null;
        if(session&&session.blobWake===cancel) session.blobWake=null;
        indicator.classList.remove('is-playing');
        URL.revokeObjectURL(url);
        callback(value);
      }
      function cancel(){cleanup(resolve);}
      if(session) session.blobWake=cancel;
      audio.onended=function(){cleanup(resolve);};
      audio.onerror=function(){cleanup(reject,new Error('Local speech playback failed'));};
      audio.play().then(function(){
        if(active&&token===generation&&currentAudio===audio) indicator.classList.add('is-playing');
      }).catch(function(error){cleanup(reject,error);});
    });
  }

  function ttsRequest(chunk,language,turnId){
    const request={text:chunk,engine:'atlas',turn_id:turnId};
    if(language) request.language=language;
    return request;
  }

  async function fetchSpeech(chunk,language,turnId,token){
    // `language` is only ever the private STT result for this turn. When it is
    // absent the field is omitted entirely and the server picks English.
    if(!active||token!==generation) throw cancelledError('Speech turn cancelled');
    const session=playbackSession;
    if(!session||session.cancelled||session.turnId!==turnId) throw cancelledError('Speech turn cancelled');
    const controller=createAbortController();
    session.controllers.add(controller);
    try{
      const response=await fetch('/api/tts',{
        method:'POST',
        headers:{'Content-Type':'application/json'},
        body:JSON.stringify(ttsRequest(chunk,language,turnId)),
        signal:controller.signal,
      });
      if(!response.ok){
        const payload=await response.json().catch(function(){return {};});
        throw new Error(payload.error||('Local speech request failed: '+response.status));
      }
      const blob=await response.blob();
      if(!active||token!==generation||session.cancelled||playbackSession!==session) throw cancelledError('Speech turn cancelled');
      return blob;
    }finally{
      session.controllers.delete(controller);
    }
  }

  function cuePoolOffset(turnId,length){
    let hash=0;
    const source=String(turnId||'');
    for(let index=0;index<source.length;index+=1) hash=((hash*31)+source.charCodeAt(index))>>>0;
    return length?hash%length:0;
  }

  function thinkingCueStillOwned(cue){
    return !!(cue&&!cue.cancelled&&thinkingCue===cue&&active&&cue.token===generation&&state==='thinking');
  }

  function scheduleNextThinkingCue(cue,delay){
    if(!thinkingCueStillOwned(cue)||cue.issued>=cue.pool.length) return;
    cue.timer=window.setTimeout(function(){
      cue.timer=null;
      issueThinkingCue(cue);
    },delay);
  }

  async function issueThinkingCue(cue){
    if(!thinkingCueStillOwned(cue)||cue.issued>=cue.pool.length) return;
    const entry=cue.pool[(cue.offset+cue.issued)%cue.pool.length];
    const cueNumber=cue.issued+1;
    cue.issued+=1;
    const controller=createAbortController();
    cue.controller=controller;
    try{
      const request=ttsRequest(entry.text,cue.language,cue.turnId+':thinking-cue:'+cueNumber);
      request.cue_id=entry.id;
      const response=await fetch(TTS_STREAM_URL,{
        method:'POST',
        headers:{'Content-Type':'application/json','Accept':'audio/pcm'},
        body:JSON.stringify(request),
        signal:controller.signal,
      });
      if(!response.ok||!response.body) throw new Error('Cached thinking cue unavailable');
      const sampleRate=parseInt(response.headers.get('X-Audio-Sample-Rate')||'22050',10);
      if(!Number.isFinite(sampleRate)||sampleRate<8000||sampleRate>96000) throw new Error('Cached thinking cue metadata invalid');
      if(!thinkingCueStillOwned(cue)) return;
      const Context=window.AudioContext||window.webkitAudioContext;
      try{cue.context=new Context({sampleRate:sampleRate,latencyHint:'interactive'});}catch(_){cue.context=new Context();}
      await cue.context.audioWorklet.addModule(WORKLET_URL);
      if(!thinkingCueStillOwned(cue)) return;
      cue.node=new AudioWorkletNode(cue.context,'atlas-pcm-playback');
      cue.gain=cue.context.createGain();
      cue.node.connect(cue.gain);
      cue.gain.connect(cue.context.destination);
      const drained=new Promise(function(resolve){
        cue.audioWake=resolve;
        cue.node.port.onmessage=function(event){
          if((event.data||{}).type==='drained'){
            const wake=cue.audioWake;
            cue.audioWake=null;
            if(wake) wake();
          }
        };
      });
      await cue.context.resume();
      indicator.classList.add('is-playing');
      const reader=response.body.getReader();
      let carry=null;
      while(thinkingCueStillOwned(cue)){
        const result=await reader.read();
        if(result.done) break;
        let bytes=result.value;
        if(carry!==null){const joined=new Uint8Array(bytes.length+1);joined[0]=carry;joined.set(bytes,1);bytes=joined;carry=null;}
        if(bytes.length%2){carry=bytes[bytes.length-1];bytes=bytes.slice(0,-1);}
        if(!bytes.length) continue;
        const copy=bytes.buffer.slice(bytes.byteOffset,bytes.byteOffset+bytes.byteLength);
        cue.node.port.postMessage({type:'push',samples:copy,sampleRate:sampleRate},[copy]);
      }
      if(thinkingCueStillOwned(cue)){
        cue.node.port.postMessage({type:'end'});
        await drained;
      }else{
        try{await reader.cancel();}catch(_){ }
      }
      cue.controller=null;
      if(cue.node){try{cue.node.disconnect();}catch(_){ }cue.node=null;}
      if(cue.context){try{cue.context.close();}catch(_){ }cue.context=null;}
      cue.gain=null;
      indicator.classList.remove('is-playing');
      if(thinkingCueStillOwned(cue)) scheduleNextThinkingCue(cue,THINKING_CUE_INTERVAL_MS);
    }catch(error){
      cue.controller=null;
      if(cue.cancelled||(error&&error.name==='AbortError')) return;
      // Cues are optional. A playback or synthesis failure must not disturb the
      // answer, retry noisily, or disable the primary hands-free conversation.
      if(thinkingCue===cue) cancelThinkingCues();
    }
  }

  function scheduleThinkingCues(token,language,turnId){
    cancelThinkingCues();
    if(!active||token!==generation||state!=='thinking') return;
    // Missing/unknown is the same fail-safe route as answer TTS: English/Amy.
    // Known STT languages remain bound exactly to their turn voice.
    const localized=normalizeSttLanguage(language)||'en';
    const pool=THINKING_CUE_POOLS[localized];
    const cue={
      token:token,
      turnId:String(turnId||token),
      language:localized,
      pool:pool,
      offset:cuePoolOffset(turnId,pool.length),
      issued:0,
      timer:null,
      controller:null,
      audioWake:null,
      context:null,
      node:null,
      gain:null,
      cancelled:false,
    };
    thinkingCue=cue;
    scheduleNextThinkingCue(cue,THINKING_CUE_FIRST_MS);
  }

  async function prepareSpeech(chunk,language,turnId,token){
    if(streamingCapability.tts&&window.ReadableStream&&window.AudioWorkletNode){
      const controller=createAbortController();
      if(playbackSession) playbackSession.controllers.add(controller);
      try{
        const response=await fetch(TTS_STREAM_URL,{
          method:'POST',
          headers:{'Content-Type':'application/json','Accept':'audio/pcm'},
          body:JSON.stringify(ttsRequest(chunk,language,turnId)),
          signal:controller.signal,
        });
        if(!response.ok||!response.body) throw new Error('Streaming speech unavailable');
        const sampleRate=parseInt(response.headers.get('X-Audio-Sample-Rate')||String(streamingCapability.tts.sample_rate||22050),10);
        const channels=parseInt(response.headers.get('X-Audio-Channels')||'1',10);
        if(!Number.isFinite(sampleRate)||sampleRate<8000||sampleRate>96000||channels!==1) throw new Error('Unsupported streaming speech format');
        return {kind:'pcm',response:response,sampleRate:sampleRate,controller:controller,token:token,chunk:chunk,language:language,turnId:turnId,started:false};
      }catch(error){
        if(playbackSession) playbackSession.controllers.delete(controller);
        if(error&&error.name==='AbortError') throw error;
        // Disable only this optional transport for the browser session. The
        // complete WAV endpoint preserves voice quality and availability.
        streamingCapability.tts=null;
      }
    }
    return {kind:'blob',blob:await fetchSpeech(chunk,language,turnId,token)};
  }

  async function ensurePcmPlayback(asset,token){
    if(!active||token!==generation) return null;
    const session=playbackSession;
    if(!session||session.cancelled) return null;
    if(session.node){
      if(session.sampleRate!==asset.sampleRate) throw new Error('Streaming speech sample rate changed mid-turn');
      return session;
    }
    const Context=window.AudioContext||window.webkitAudioContext;
    let context;
    try{
      // Keep Piper at its native rate and let the browser/audio device own any
      // final hardware conversion; the worklet interpolator is a fallback.
      context=new Context({sampleRate:asset.sampleRate,latencyHint:'interactive'});
    }catch(_){
      context=new Context();
    }
    await context.audioWorklet.addModule(WORKLET_URL);
    if(!active||token!==generation){context.close();return;}
    const node=new AudioWorkletNode(context,'atlas-pcm-playback');
    if(!session||session.cancelled){context.close();return;}
    const gain=context.createGain();
    session.context=context;
    session.node=node;
    session.gain=gain;
    session.sampleRate=asset.sampleRate;
    session.bufferedFrames=0;
    session.playbackEnded=false;
    node.connect(gain);
    gain.connect(context.destination);
    await context.resume();
    session.drained=new Promise(function(resolve,reject){
      session.drainWake=resolve;
      session.drainReject=reject;
    });
    indicator.classList.add('is-playing');
    node.port.onmessage=function(event){
      const data=event.data||{};
      if(data.type==='buffer'){
        session.bufferedFrames=data.frames||0;
        if(session.bufferedFrames<session.sampleRate&&session.lowWaterWake){
          const wake=session.lowWaterWake;
          session.lowWaterWake=null;
          wake();
        }
      }else if(data.type==='drained'){
        session.playbackEnded=true;
        const wake=session.drainWake;
        session.drainWake=null;
        if(wake) wake();
      }else if(data.type==='error'){
        const reject=session.drainReject;
        session.drainReject=null;
        if(reject) reject(new Error(data.error||'Streaming speech playback failed'));
      }
    };
    return session;
  }

  async function playPcm(asset,token){
    const session=await ensurePcmPlayback(asset,token);
    if(!session) return;
    const reader=asset.response.body.getReader();
    let carry=null;
    try{
      while(active&&token===generation&&!session.cancelled){
        if(session.bufferedFrames>asset.sampleRate*2){
          await new Promise(function(resolve){
            let completed=false;
            const wake=function(){if(completed)return;completed=true;session.lowWaterWake=null;resolve();};
            session.lowWaterWake=wake;
            window.setTimeout(wake,3000);
          });
        }
        const result=await reader.read();
        if(result.done) break;
        let bytes=result.value;
        if(carry!==null){
          const joined=new Uint8Array(bytes.length+1);
          joined[0]=carry;joined.set(bytes,1);bytes=joined;carry=null;
        }
        if(bytes.length%2){carry=bytes[bytes.length-1];bytes=bytes.slice(0,-1);}
        if(!bytes.length) continue;
        const copy=bytes.buffer.slice(bytes.byteOffset,bytes.byteOffset+bytes.byteLength);
        session.bufferedFrames+=bytes.byteLength/2;
        asset.started=true;
        session.node.port.postMessage({type:'push',samples:copy,sampleRate:asset.sampleRate},[copy]);
      }
    }finally{
      if((!active||token!==generation||session.cancelled)){try{await reader.cancel();}catch(_){ }}
      session.controllers.delete(asset.controller);
    }
  }

  async function drainPcmPlayback(session,token){
    if(!session||!session.node||session.cancelled||!active||token!==generation) return;
    if(session.playbackEnded) return;
    session.node.port.postMessage({type:'end'});
    await session.drained;
  }

  async function closePcmBeforeBlob(session,token){
    if(!session||!session.node) return;
    await drainPcmPlayback(session,token);
    if(session.node){try{session.node.disconnect();}catch(_){ }session.node=null;}
    if(session.context){try{session.context.close();}catch(_){ }session.context=null;}
    session.gain=null;
    session.drained=null;
    indicator.classList.remove('is-playing');
  }

  async function playPrepared(asset,token){
    if(asset.kind!=='pcm'){
      if(playbackSession&&playbackSession.node) await closePcmBeforeBlob(playbackSession,token);
      return playBlob(asset.blob,token);
    }
    try{
      return await playPcm(asset,token);
    }catch(error){
      if(asset.started) throw error;
      streamingCapability.tts=null;
      if(playbackSession&&playbackSession.node) await closePcmBeforeBlob(playbackSession,token);
      return playBlob(await fetchSpeech(asset.chunk,asset.language,asset.turnId,token),token);
    }
  }

  function nextSpeechChunk(turn){
    if(turn.cancelled) return Promise.resolve(null);
    if(turn.queue.length) return Promise.resolve(turn.queue.shift());
    if(turn.final) return Promise.resolve(null);
    return new Promise(function(resolve){turn.waiters.push(resolve);});
  }

  function enqueueSpeech(turn,chunks){
    chunks.forEach(function(chunk){
      if(!chunk) return;
      if(turn.waiters.length) turn.waiters.shift()(chunk); else turn.queue.push(chunk);
    });
  }

  function finishSpeechQueue(turn){
    turn.final=true;
    while(turn.waiters.length&&!turn.queue.length) turn.waiters.shift()(null);
  }

  async function runSpeechQueue(turn){
    if(turn.running) return;
    turn.running=true;
    playbackSession={turnId:turn.turnId,controllers:new Set(),context:null,node:null,gain:null,sampleRate:0,bufferedFrames:0,drained:null,drainReject:null,playbackEnded:false,cancelled:false,lowWaterWake:null,drainWake:null,blobWake:null};
    const session=playbackSession;
    try{
      let chunk=await nextSpeechChunk(turn);
      let current=chunk?prepareSpeech(chunk,turn.language,turn.turnId,turn.token):null;
      while(current){
        const asset=await current;
        // At most one later synthesis request exists while this asset plays.
        // If streaming has not produced it yet, the waiter starts it the
        // instant a punctuation-safe chunk arrives.
        const next=nextSpeechChunk(turn);
        const nextPrepared=next.then(function(value){
          return value?prepareSpeech(value,turn.language,turn.turnId,turn.token):null;
        });
        // Barge-in can abort both the playing request and its one-ahead request.
        // Observe the latter even when the cancelled current turn returns first.
        nextPrepared.catch(function(){ });
        await playPrepared(asset,turn.token);
        if(!active||turn.token!==generation||turn.cancelled||session.cancelled) return;
        current=await nextPrepared;
      }
      await drainPcmPlayback(session,turn.token);
      if(turn.final&&active&&turn.token===generation&&!turn.cancelled) restartSoon(turn.token,300);
    }catch(error){
      if(active&&turn.token===generation&&!turn.cancelled){
        const message=errorMessage(error,'Local speech is unavailable');
        setState('error',message);
        toast(message);
        restartSoon(turn.token,500);
      }
    }finally{
      if(playbackSession===session) stopPlayback();
      if(speechTurn===turn) speechTurn=null;
    }
  }

  function currentAssistantText(){
    const rows=assistantRows();
    if(!rows.length) return '';
    const row=rows[rows.length-1];
    const text=readAssistantRow(row);
    if(assistantBaseline&&row===assistantBaseline.row&&text===assistantBaseline.text) return '';
    if(assistantBaseline&&rows.length<assistantBaseline.count) return '';
    return cleanForSpeech(text);
  }

  function ensureSpeechTurn(token){
    if(speechTurn) return speechTurn;
    speechTurn={
      token:token,
      turnId:thinkingTurnId||String(token)+'-'+String(++turnSequence),
      language:takeSttLanguage(token),
      sourceText:'',
      consumed:0,
      first:true,
      queue:[],
      waiters:[],
      final:false,
      cancelled:false,
      running:false,
    };
    return speechTurn;
  }

  function pumpAssistantResponse(token,isFinal){
    if(!active||token!==generation||(state!=='thinking'&&state!=='speaking')) return;
    const currentSession=(typeof S!=='undefined'&&S.session)?S.session.session_id:null;
    if(thinkingSession&&currentSession&&thinkingSession!==currentSession){
      thinkingSession=null;
      thinkingTurnId='';
      clearSttLanguage();
      stopResponseObserver();
      cancelThinkingCues();
      cancelSpeechTurn();
      stopPlayback();
      restartSoon(token,250);
      return;
    }
    const text=currentAssistantText();
    if(!text){
      if(isFinal){thinkingSession=null;thinkingTurnId='';clearSttLanguage();stopResponseObserver();cancelThinkingCues();restartSoon(token,250);}
      return;
    }
    // Any answer text, even a not-yet-speakable partial clause, owns the audio
    // timeline from this point forward. A cue must never overlap or become part
    // of the answer queue.
    cancelThinkingCues();
    const turn=ensureSpeechTurn(token);
    if(text.length<turn.sourceText.length||!text.startsWith(turn.sourceText)){
      // Renderers can revise the still-unspoken tail. Already-spoken text is
      // immutable. On the completion callback, advance from the old spoken
      // offset and close the queue even when the renderer rewrote an earlier
      // span; replaying the revised prefix would be more disruptive than
      // preserving the already-heard words.
      if(turn.consumed>0){
        if(!isFinal) return;
        thinkingSession=null;
        thinkingTurnId='';
        stopResponseObserver();
        const revisedTail=text.slice(Math.min(turn.consumed,text.length)).trim();
        if(revisedTail){
          const revised=adaptiveChunks(revisedTail,true,false);
          enqueueSpeech(turn,revised.chunks.length?revised.chunks:[revisedTail]);
          turn.consumed=text.length;
        }
        finishSpeechQueue(turn);
        return;
      }
      turn.sourceText='';
    }
    turn.sourceText=text;
    const remaining=text.slice(turn.consumed).trimStart();
    const skipped=text.slice(turn.consumed).length-remaining.length;
    const extracted=adaptiveChunks(remaining,!!isFinal,turn.first);
    if(extracted.chunks.length){
      turn.first=false;
      turn.consumed+=skipped+extracted.consumed;
      enqueueSpeech(turn,extracted.chunks);
      setState('speaking');
      runSpeechQueue(turn);
    }
    if(isFinal){
      thinkingSession=null;
      thinkingTurnId='';
      stopResponseObserver();
      const tail=text.slice(turn.consumed).trim();
      if(tail){enqueueSpeech(turn,[tail]);turn.consumed=text.length;}
      finishSpeechQueue(turn);
    }
  }

  function startResponseObserver(token){
    stopResponseObserver();
    // A bounded poll is deliberately used in addition to the upstream
    // completion callback. It sees data-raw-text while SSE is still appending,
    // so the first complete sentence can reach Piper before generation ends.
    responsePollTimer=window.setInterval(function(){pumpAssistantResponse(token,false);},75);
  }

  function speakResponse(token){
    pumpAssistantResponse(token,true);
  }

  function validStreamingCapability(payload){
    if(!payload||typeof payload!=='object') return {tts:null,stt:null,preflight:null};
    const tts=payload.tts&&payload.tts.available===true&&payload.tts.transport==='http'&&payload.tts.format==='pcm_s16le'?payload.tts:null;
    const stt=payload.stt&&payload.stt.available===true&&payload.stt.transport==='websocket'&&payload.stt.format==='pcm_s16le'&&payload.stt.sample_rate===16000?payload.stt:null;
    const preflight=payload.preflight&&payload.preflight.available===true&&payload.preflight.path===VOICE_PREFLIGHT_URL&&payload.preflight.advisory===true?payload.preflight:null;
    return {tts:tts,stt:stt,preflight:preflight};
  }

  async function discoverStreamingCapability(){
    try{
      const response=await fetch(STREAMING_CAPABILITY_URL,{cache:'no-store'});
      if(!response.ok) return;
      streamingCapability=validStreamingCapability(await response.json());
    }catch(_){
      streamingCapability={tts:null,stt:null,preflight:null};
    }
  }

  function activate(){
    generation+=1;
    const token=generation;
    active=true;
    clearErrorTimer();
    clearSttLanguage();
    modeBtn.classList.add('active');
    toast('Hands-free private voice mode on');
    if(typeof window.stopTTS==='function') window.stopTTS();
    if(typeof S!=='undefined'&&S.busy){setState('thinking');return;}
    startListening(token);
  }

  function onVoiceClick(event){
    if(!ready) return;
    event.preventDefault();
    event.stopImmediatePropagation();
    if(active) deactivate(true); else activate();
  }

  async function initialize(){
    try{
      const response=await fetch('/api/transcribe/capability',{cache:'no-store'});
      const capability=await response.json().catch(function(){return {};});
      if(!response.ok||!capability.available||capability.provider!=='local_command') return;
      ready=true;
      discoverStreamingCapability();
      if(localStorage.getItem('hermes-atlas-voice-initialized')!=='1'){
        localStorage.setItem('hermes-atlas-voice-initialized','1');
        localStorage.setItem('hermes-voice-mode-button','true');
        localStorage.setItem('hermes-tts-engine','atlas');
        localStorage.setItem('hermes-tts-enabled','true');
      }
      // Move existing installations to the lower-latency silence window once;
      // subsequent user changes remain untouched.
      if(localStorage.getItem('hermes-atlas-voice-latency-v2')!=='1'){
        localStorage.setItem('hermes-atlas-voice-latency-v2','1');
        localStorage.setItem('hermes-voice-silence-ms','1100');
      }
      const selector=document.getElementById('settingsTtsEngine');
      if(selector&&!selector.querySelector('option[value="atlas"]')){
        const option=document.createElement('option');
        option.value='atlas';
        option.textContent='Atlas Jetson (private)';
        selector.insertBefore(option,selector.firstChild);
      }
      modeBtn.style.display=localStorage.getItem('hermes-voice-mode-button')==='false'?'none':'';
      modeBtn.addEventListener('click',onVoiceClick,true);
      window._applyVoiceModePref=function(){
        if(typeof originalApplyPreference==='function') originalApplyPreference();
        if(ready){
          const enabled=localStorage.getItem('hermes-voice-mode-button')!=='false';
          modeBtn.style.display=enabled?'':'none';
          if(!enabled&&active) deactivate(false);
        }
      };
      window.autoReadLastAssistant=function(){
        if(active){
          if(suppressAutoRead||bargeCancelPromise||state==='listening'||state==='transcribing') return;
          if(state==='thinking'||state==='speaking'){speakResponse(generation);return;}
        }
        if(typeof originalAutoRead==='function') originalAutoRead.apply(this,arguments);
      };
      window._voiceModeActive=function(){return active;};
      window._voiceModeDeactivate=function(){deactivate(false);};
      window._voiceModeImmediateSend=function(){
        if(active&&recorder&&recorder.state!=='inactive') recorder.stop();
      };
    }catch(_){
      // The upstream browser voice implementation remains available as fallback.
    }
  }

  initialize();
})();