(() => {
  "use strict";

  const TARGET_SAMPLE_RATE = 16000;
  const MAX_RECORDING_MS = 28000;
  const NO_SPEECH_TIMEOUT_MS = 8000;
  const ENDPOINT_SILENCE_MS = 1050;
  const STATUS_RESET_MS = 5000;
  const MICROPHONE_CONNECT_TIMEOUT_MS = 12000;
  const PREFERRED_MICROPHONE = /TAKSTAR\s*V2/i;
  const DEBUG = new URLSearchParams(window.location.search).get("speechDebug") === "1"
    || window.localStorage.getItem("speechDebug") === "1";
  const speech = {
    phase: "idle",
    backendReady: false,
    stream: null,
    context: null,
    contextPromise: null,
    workletReady: false,
    workletFailed: false,
    source: null,
    captureNode: null,
    silentGain: null,
    chunks: [],
    totalSamples: 0,
    sampleRate: 0,
    startedAt: 0,
    speechStartSample: null,
    lastVoiceSample: null,
    consecutiveVoiceSamples: 0,
    noiseFloor: 0.003,
    statusTimer: null,
    generation: 0,
    utteranceId: "",
    finishPromise: null,
    applyingResult: false,
    lastResult: null,
  };

  const elements = () => ({
    button: document.querySelector("#speechDictationButton"),
    composer: document.querySelector("#speechDictationButton")?.closest(".command-composer"),
    input: document.querySelector("#utterance"),
    status: document.querySelector("#speechDictationStatus"),
  });

  function debug(stage, details = {}) {
    if (!DEBUG) return;
    console.debug("[speech]", { utteranceId: speech.utteranceId, stage, ...details });
  }

  function announce(message) {
    const notify = window.CognitiveAgentConsole?.notify;
    if (typeof notify === "function") notify(message);
  }

  function setPhase(phase, message = "") {
    speech.phase = phase;
    const { button, composer, status } = elements();
    if (!button || !composer || !status) return;
    window.clearTimeout(speech.statusTimer);
    composer.dataset.speechState = phase;
    status.textContent = message;
    button.classList.toggle("is-listening", phase === "listening");
    button.classList.toggle("is-processing", phase === "processing");
    button.disabled = phase === "processing" || (!speech.backendReady && phase !== "listening");
    button.setAttribute("aria-pressed", String(phase === "listening"));
    button.setAttribute(
      "aria-label",
      phase === "listening" ? "结束语音听写" : phase === "processing" ? "正在转写语音" : "开始语音听写",
    );
    button.title = phase === "listening"
      ? "点击结束听写"
      : speech.backendReady
        ? "语音听写（自动识别说话结束）"
        : "语音识别模型未就绪";
    if (["success", "error"].includes(phase)) {
      speech.statusTimer = window.setTimeout(() => setPhase("idle"), STATUS_RESET_MS);
    }
  }

  function microphoneErrorMessage(error) {
    switch (error?.name) {
      case "NotAllowedError":
        return "未获得麦克风权限，请在浏览器地址栏允许访问麦克风。";
      case "NotFoundError":
        return "没有找到可用麦克风，请检查 TAKSTAR V2 接收器。";
      case "NotReadableError":
        return "麦克风正被其他程序占用，请关闭占用程序后重试。";
      case "OverconstrainedError":
        return "TAKSTAR V2 当前不可用，请重新连接接收器。";
      case "SecurityError":
        return "当前页面不允许访问麦克风，请使用 HTTPS 或本机地址。";
      case "TimeoutError":
        return "等待麦克风授权超时，请允许访问后重试。";
      default:
        return "无法启动麦克风，请检查设备连接和浏览器权限。";
    }
  }

  async function getUserMediaWithTimeout(constraints) {
    let expired = false;
    let timer = 0;
    const request = navigator.mediaDevices.getUserMedia(constraints);
    const timeout = new Promise((_, reject) => {
      timer = window.setTimeout(() => {
        expired = true;
        reject(new DOMException("microphone permission timed out", "TimeoutError"));
      }, MICROPHONE_CONNECT_TIMEOUT_MS);
    });
    request.then((lateStream) => {
      if (expired) lateStream.getTracks().forEach((track) => track.stop());
    }).catch(() => {});
    try {
      return await Promise.race([request, timeout]);
    } finally {
      window.clearTimeout(timer);
    }
  }

  async function preferredMicrophoneStream() {
    const constraints = {
      channelCount: 1,
      echoCancellation: true,
      noiseSuppression: true,
      autoGainControl: true,
    };
    let stream = await getUserMediaWithTimeout({ audio: constraints, video: false });
    const currentTrack = stream.getAudioTracks()[0];
    const devices = await navigator.mediaDevices.enumerateDevices();
    const preferred = devices.find(
      (device) => device.kind === "audioinput" && PREFERRED_MICROPHONE.test(device.label),
    );
    if (preferred && preferred.deviceId !== currentTrack?.getSettings?.().deviceId) {
      stream.getTracks().forEach((track) => track.stop());
      stream = await getUserMediaWithTimeout({
        audio: { ...constraints, deviceId: { exact: preferred.deviceId } },
        video: false,
      });
    }
    return stream;
  }

  async function ensureAudioContext() {
    if (speech.context && speech.context.state !== "closed") {
      await speech.context.resume();
      return speech.context;
    }
    if (speech.contextPromise) return speech.contextPromise;
    speech.contextPromise = (async () => {
      const AudioContext = window.AudioContext || window.webkitAudioContext;
      const context = new AudioContext({ latencyHint: "interactive" });
      await context.resume();
      if (context.audioWorklet && window.AudioWorkletNode) {
        try {
          await context.audioWorklet.addModule("/speech-audio-worklet.js?v=sensevoice-4");
          speech.workletReady = true;
        } catch (error) {
          speech.workletFailed = true;
          debug("audio_worklet_fallback", { message: error?.message || String(error) });
        }
      } else {
        speech.workletFailed = true;
      }
      speech.context = context;
      return context;
    })();
    try {
      return await speech.contextPromise;
    } finally {
      speech.contextPromise = null;
    }
  }

  function audioRms(samples) {
    let sum = 0;
    for (let index = 0; index < samples.length; index += 1) sum += samples[index] * samples[index];
    return Math.sqrt(sum / Math.max(1, samples.length));
  }

  function handleAudio(chunk, generation) {
    if (speech.phase !== "listening" || generation !== speech.generation) return;
    speech.chunks.push(chunk);
    speech.totalSamples += chunk.length;
    const elapsed = performance.now() - speech.startedAt;
    const rms = audioRms(chunk);
    if (elapsed < 700) speech.noiseFloor = (speech.noiseFloor * 0.82) + (rms * 0.18);
    const voiceThreshold = Math.max(0.009, Math.min(0.035, speech.noiseFloor * 2.8));
    if (rms >= voiceThreshold) {
      speech.consecutiveVoiceSamples += chunk.length;
      if (speech.consecutiveVoiceSamples >= speech.sampleRate * 0.09) {
        if (speech.speechStartSample === null) {
          speech.speechStartSample = Math.max(0, speech.totalSamples - (speech.sampleRate * 0.35));
          setPhase("listening", "听到声音了，请继续说…");
          debug("speech_started", { sample: speech.speechStartSample, voiceThreshold });
        }
        speech.lastVoiceSample = speech.totalSamples;
      }
    } else {
      speech.consecutiveVoiceSamples = 0;
    }
    if (
      speech.lastVoiceSample !== null
      && speech.totalSamples - speech.lastVoiceSample >= speech.sampleRate * (ENDPOINT_SILENCE_MS / 1000)
    ) {
      void finishDictation();
    } else if (speech.speechStartSample === null && elapsed >= NO_SPEECH_TIMEOUT_MS) {
      void cancelDictation("未检测到说话声，请靠近麦克风重试。");
    } else if (elapsed >= MAX_RECORDING_MS) {
      void finishDictation();
    }
  }

  function connectCapture(context, generation) {
    speech.source = context.createMediaStreamSource(speech.stream);
    speech.silentGain = context.createGain();
    speech.silentGain.gain.value = 0;
    if (speech.workletReady && !speech.workletFailed) {
      speech.captureNode = new AudioWorkletNode(context, "speech-capture-processor", {
        numberOfInputs: 1,
        numberOfOutputs: 1,
        channelCount: 1,
      });
      speech.captureNode.port.onmessage = (event) => {
        handleAudio(new Float32Array(event.data), generation);
      };
      debug("capture_connected", { implementation: "AudioWorklet" });
    } else {
      speech.captureNode = context.createScriptProcessor(2048, 1, 1);
      speech.captureNode.onaudioprocess = (event) => {
        handleAudio(new Float32Array(event.inputBuffer.getChannelData(0)), generation);
      };
      debug("capture_connected", { implementation: "ScriptProcessor-fallback" });
    }
    speech.source.connect(speech.captureNode);
    speech.captureNode.connect(speech.silentGain);
    speech.silentGain.connect(context.destination);
  }

  async function startDictation() {
    if (speech.phase !== "idle" && !["success", "error"].includes(speech.phase)) return;
    if (!speech.backendReady) {
      setPhase("error", "语音识别模型未就绪");
      return;
    }
    if (!window.isSecureContext || !navigator.mediaDevices?.getUserMedia) {
      setPhase("error", "请使用 HTTPS 或 127.0.0.1 开启语音听写");
      announce("当前页面不支持安全的麦克风访问");
      return;
    }
    const generation = speech.generation + 1;
    speech.generation = generation;
    speech.utteranceId = `web-${crypto.randomUUID?.() || `${Date.now()}-${generation}`}`;
    try {
      setPhase("processing", "正在连接麦克风…");
      speech.stream = await preferredMicrophoneStream();
      if (generation !== speech.generation) return;
      const context = await ensureAudioContext();
      speech.sampleRate = context.sampleRate;
      speech.chunks = [];
      speech.totalSamples = 0;
      speech.startedAt = performance.now();
      speech.speechStartSample = null;
      speech.lastVoiceSample = null;
      speech.consecutiveVoiceSamples = 0;
      speech.noiseFloor = 0.003;
      connectCapture(context, generation);
      const trackLabel = speech.stream.getAudioTracks()[0]?.label || "默认麦克风";
      setPhase("listening", `正在听写 · ${trackLabel}`);
      debug("utterance_started", { sampleRate: speech.sampleRate, trackLabel });
    } catch (error) {
      await releaseMicrophone();
      const message = microphoneErrorMessage(error);
      setPhase("error", message);
      announce(message);
    }
  }

  async function releaseMicrophone({ closeContext = false } = {}) {
    if (speech.captureNode?.port) speech.captureNode.port.onmessage = null;
    if (speech.captureNode && "onaudioprocess" in speech.captureNode) {
      speech.captureNode.onaudioprocess = null;
    }
    for (const node of [speech.source, speech.captureNode, speech.silentGain]) {
      try { node?.disconnect(); } catch (_error) { /* already disconnected */ }
    }
    speech.stream?.getTracks().forEach((track) => track.stop());
    speech.stream = null;
    speech.source = null;
    speech.captureNode = null;
    speech.silentGain = null;
    if (closeContext && speech.context && speech.context.state !== "closed") {
      try { await speech.context.close(); } catch (_error) { /* page is closing */ }
      speech.context = null;
      speech.workletReady = false;
    }
  }

  function concatenateChunks() {
    const combined = new Float32Array(speech.totalSamples);
    let offset = 0;
    for (const chunk of speech.chunks) {
      combined.set(chunk, offset);
      offset += chunk.length;
    }
    const start = Math.max(0, Math.floor(speech.speechStartSample || 0));
    const end = Math.min(
      combined.length,
      Math.ceil((speech.lastVoiceSample || combined.length) + (speech.sampleRate * 0.45)),
    );
    return combined.slice(start, end);
  }

  function downsample(samples, inputRate) {
    if (inputRate === TARGET_SAMPLE_RATE) return samples;
    const ratio = inputRate / TARGET_SAMPLE_RATE;
    const output = new Float32Array(Math.max(1, Math.floor(samples.length / ratio)));
    for (let outputIndex = 0; outputIndex < output.length; outputIndex += 1) {
      const start = Math.floor(outputIndex * ratio);
      const end = Math.max(start + 1, Math.min(samples.length, Math.floor((outputIndex + 1) * ratio)));
      let sum = 0;
      for (let inputIndex = start; inputIndex < end; inputIndex += 1) sum += samples[inputIndex];
      output[outputIndex] = sum / (end - start);
    }
    return output;
  }

  function encodePcm16Wav(samples) {
    const buffer = new ArrayBuffer(44 + (samples.length * 2));
    const view = new DataView(buffer);
    const writeAscii = (offset, value) => {
      for (let index = 0; index < value.length; index += 1) view.setUint8(offset + index, value.charCodeAt(index));
    };
    writeAscii(0, "RIFF");
    view.setUint32(4, 36 + (samples.length * 2), true);
    writeAscii(8, "WAVE");
    writeAscii(12, "fmt ");
    view.setUint32(16, 16, true);
    view.setUint16(20, 1, true);
    view.setUint16(22, 1, true);
    view.setUint32(24, TARGET_SAMPLE_RATE, true);
    view.setUint32(28, TARGET_SAMPLE_RATE * 2, true);
    view.setUint16(32, 2, true);
    view.setUint16(34, 16, true);
    writeAscii(36, "data");
    view.setUint32(40, samples.length * 2, true);
    for (let index = 0; index < samples.length; index += 1) {
      const sample = Math.max(-1, Math.min(1, samples[index]));
      view.setInt16(44 + (index * 2), sample < 0 ? sample * 32768 : sample * 32767, true);
    }
    return buffer;
  }

  async function transcribe(wav, utteranceId) {
    const controller = new AbortController();
    const timeout = window.setTimeout(() => controller.abort(), 45000);
    try {
      const response = await fetch("/api/speech/transcribe", {
        method: "POST",
        credentials: "same-origin",
        cache: "no-store",
        headers: {
          Accept: "application/json",
          "Content-Type": "audio/wav",
          "X-Speech-Utterance-Id": utteranceId,
        },
        body: wav,
        signal: controller.signal,
      });
      const payload = await response.json().catch(() => ({}));
      if (!response.ok) throw new Error(payload.message || `语音转写失败（HTTP ${response.status}）`);
      debug("server_result", payload);
      return payload;
    } finally {
      window.clearTimeout(timeout);
    }
  }

  function applyResult(result) {
    const { input } = elements();
    if (!input) throw new Error("没有找到一句话编排输入框");
    const cleanText = String(result.clean_text || result.text || "").trim();
    const peripheralEligible = result.peripheral_routing?.execution_eligible === true;
    const inputText = peripheralEligible
      ? String(result.routing_text || result.raw_text || cleanText).trim()
      : cleanText;
    const commands = Array.isArray(result.commands) ? result.commands : [];
    if (!inputText || (commands.length === 0 && !peripheralEligible)) {
      window.dispatchEvent(new CustomEvent("cognitive-agent:speech-result", { detail: result }));
      return false;
    }
    speech.applyingResult = true;
    input.value = inputText.slice(0, input.maxLength || 1000);
    input.dataset.speechUncertain = String(result.uncertain === true);
    input.dataset.speechExecutionEligible = String(
      result.execution_eligible === true || peripheralEligible,
    );
    input.dataset.speechSemanticStatus = String(result.semantic_status || "");
    input.dataset.speechValue = input.value.trim();
    input.dataset.speechUtteranceId = String(result.utterance_id || "");
    input.dispatchEvent(new Event("input", { bubbles: true }));
    speech.applyingResult = false;
    input.focus({ preventScroll: true });
    window.dispatchEvent(new CustomEvent("cognitive-agent:speech-result", { detail: result }));
    return true;
  }

  async function finishDictation() {
    if (speech.finishPromise) return speech.finishPromise;
    if (speech.phase !== "listening") return undefined;
    speech.finishPromise = (async () => {
      setPhase("processing", "说话结束，正在识别并理解指令…");
      const hadSpeech = speech.speechStartSample !== null;
      const samples = hadSpeech ? concatenateChunks() : null;
      const inputRate = speech.sampleRate;
      const utteranceId = speech.utteranceId;
      await releaseMicrophone();
      speech.chunks = [];
      if (!hadSpeech || !samples?.length) {
        setPhase("error", "未检测到说话声，请重试");
        return;
      }
      try {
        const wav = encodePcm16Wav(downsample(samples, inputRate));
        const result = await transcribe(wav, utteranceId);
        speech.lastResult = result;
        const applied = applyResult(result);
        const latency = Math.round(result.timings?.total_ms ?? result.inference_ms ?? 0);
        if (!applied) {
          setPhase("success", `未形成可执行控制指令 · ${latency} ms`);
          announce("已保留原始转录，但没有激活控制指令");
        } else if (result.peripheral_routing?.execution_eligible === true) {
          const count = Number(result.peripheral_routing.action_count || 1);
          setPhase("success", `已识别为 ${count} 条外设控制指令 · ${latency} ms`);
          announce("语音已匹配当前 NFC 外设的已学习控制指令");
        } else if (result.semantic_status === "recognized_unsupported") {
          setPhase("success", `已识别，但当前车辆能力不支持 · ${latency} ms`);
          announce("已完整保留用户语义，但当前车辆能力不支持执行");
        } else if (result.semantic_status === "incomplete") {
          setPhase("success", `已识别，但控制参数不完整 · ${latency} ms`);
          announce("语音中的关键控制参数不完整，当前不会执行");
        } else if (result.uncertain === true) {
          setPhase("success", `已转写，但存在歧义，请修改确认 · ${latency} ms`);
          announce("语音结果需要人工确认，当前不会直接执行");
        } else {
          setPhase("success", `已理解为 ${result.commands.length} 条指令 · ${latency} ms`);
          announce("语音已转换为理解式控制指令");
        }
      } catch (error) {
        const message = error?.name === "AbortError" ? "语音转写超时，请重试。" : error.message;
        setPhase("error", message || "语音转写失败，请重试");
        announce(message || "语音转写失败");
      }
    })();
    try {
      return await speech.finishPromise;
    } finally {
      speech.finishPromise = null;
    }
  }

  async function cancelDictation(message = "已取消语音听写") {
    if (!speech.stream && speech.phase === "idle") return;
    speech.phase = "processing";
    speech.generation += 1;
    await releaseMicrophone();
    speech.chunks = [];
    setPhase("error", message);
  }

  async function loadSpeechStatus() {
    const { button } = elements();
    if (!button) return;
    if (!window.isSecureContext || !navigator.mediaDevices?.getUserMedia) {
      button.disabled = true;
      setPhase("error", "语音听写需要 HTTPS 或本机地址");
      return;
    }
    try {
      const response = await fetch("/api/speech/status", {
        credentials: "same-origin",
        cache: "no-store",
        headers: { Accept: "application/json" },
      });
      const status = await response.json();
      speech.backendReady = response.ok && status.enabled === true;
      debug("backend_status", status);
      setPhase("idle");
      if (!speech.backendReady) {
        button.disabled = true;
        button.title = "SenseVoiceSmall 模型未部署";
      }
    } catch (_error) {
      speech.backendReady = false;
      button.disabled = true;
      button.title = "无法连接语音识别服务";
    }
  }

  function clearSpeechGuardOnManualEdit(event) {
    if (speech.applyingResult || !event.isTrusted) return;
    const { input } = elements();
    if (!input) return;
    delete input.dataset.speechUncertain;
    delete input.dataset.speechExecutionEligible;
    delete input.dataset.speechSemanticStatus;
    delete input.dataset.speechValue;
    delete input.dataset.speechUtteranceId;
  }

  function initialize() {
    const { button, input } = elements();
    if (!button) return;
    button.addEventListener("click", () => {
      if (speech.phase === "listening") void finishDictation();
      else void startDictation();
    });
    input?.addEventListener("input", clearSpeechGuardOnManualEdit);
    document.addEventListener("keydown", (event) => {
      if (event.key === "Escape" && speech.phase === "listening") {
        event.preventDefault();
        void cancelDictation();
      }
    });
    document.addEventListener("visibilitychange", () => {
      if (document.hidden && speech.phase === "listening") void cancelDictation();
    });
    window.addEventListener("pagehide", () => { void releaseMicrophone({ closeContext: true }); });
    void loadSpeechStatus();
  }

  window.CognitiveAgentSpeech = {
    get lastResult() { return speech.lastResult; },
    get debugEnabled() { return DEBUG; },
  };
  document.addEventListener("DOMContentLoaded", initialize);
})();