const $ = (id) => document.getElementById(id);
let current = null;
function status(text) {
  $("status").textContent = text;
}
function controls(busy) {
  $("start").disabled = busy || !$("model").value;
  $("load").disabled = busy;
  $("model").disabled = busy;
  $("finish").disabled = !busy;
  $("cancel").disabled = !busy;
}
async function stopMic(s) {
  s.stream?.getTracks().forEach((track) => track.stop());
  s.stream = null;
  s.node?.disconnect();
  s.node = null;
  if (s.context && s.context.state !== "closed")
    await s.context.close().catch(() => {});
}
async function cleanup(s, message) {
  if (s.closed) return;
  s.closed = true;
  await stopMic(s);
  if (s.ws && s.ws.readyState < WebSocket.CLOSING) s.ws.close();
  if (current === s) {
    current = null;
    controls(false);
    if (message) status(message);
  }
}
$("load").addEventListener("click", async () => {
  try {
    const token = $("token").value.trim();
    const response = await fetch("/api/models", {
      headers: { Authorization: `Bearer ${token}` },
    });
    if (!response.ok)
      throw new Error(
        response.status === 401 ? "访问令牌无效" : "读取模型失败",
      );
    const models = await response.json();
    $("model").replaceChildren();
    let available = 0;
    for (const model of models) {
      const option = document.createElement("option");
      option.value = model.id;
      option.textContent = `${model.id}${model.enabled ? "" : "（服务端未配置凭据）"}`;
      option.disabled = !model.enabled;
      $("model").append(option);
      if (model.enabled) available++;
    }
    const enabled = [...$("model").options].find((o) => !o.disabled);
    $("model").value = enabled?.value || "";
    controls(false);
    status(
      available ? "配置已读取，可开始测试" : "没有可用凭据；LLM/TTS 未启用",
    );
  } catch (error) {
    status(error.message);
  }
});
$("model").addEventListener("change", () => controls(false));
$("start").addEventListener("click", async () => {
  if (current) return;
  if (!window.isSecureContext || !navigator.mediaDevices?.getUserMedia) {
    status(
      "麦克风需要 HTTPS 或 localhost。可使用 SSH 隧道，不要关闭浏览器安全设置。",
    );
    return;
  }
  const token = $("token").value.trim();
  if (!/^[A-Za-z0-9_-]{32,}$/.test(token)) {
    status("请输入有效的服务访问令牌");
    return;
  }
  const s = { closed: false };
  current = s;
  controls(true);
  status("正在请求麦克风…");
  try {
    const stream = await navigator.mediaDevices.getUserMedia({
      audio: {
        channelCount: 1,
        echoCancellation: true,
        noiseSuppression: true,
      },
      video: false,
    });
    if (s.closed) {
      stream.getTracks().forEach((track) => track.stop());
      return;
    }
    s.stream = stream;
    s.context = new AudioContext({ sampleRate: 16000 });
    if (s.context.sampleRate !== 16000)
      throw new Error("浏览器无法提供 16 kHz 音频，已停止，避免发送错误采样率");
    await s.context.audioWorklet.addModule("/pcm-worklet.js");
    if (s.closed) return;
    const ws = new WebSocket(
      `${location.protocol === "https:" ? "wss:" : "ws:"}//${location.host}/ws`,
      ["asr.v1", `auth.${token}`],
    );
    s.ws = ws;
    ws.binaryType = "arraybuffer";
    ws.onclose = () => {
      void cleanup(s, "连接已结束");
    };
    ws.onerror = () => {
      void cleanup(s, "WebSocket 连接失败，请检查访问令牌、Origin 和服务状态");
    };
    ws.onopen = () => {
      if (!s.closed)
        ws.send(JSON.stringify({ type: "start", model: $("model").value }));
    };
    ws.onmessage = async (event) => {
      if (s.closed || typeof event.data !== "string") return;
      try {
        const data = JSON.parse(event.data);
        if (data.type === "asr-started") {
          s.node = new AudioWorkletNode(s.context, "pcm16");
          s.node.port.onmessage = ({ data: pcm }) => {
            if (s.closed || ws.readyState !== WebSocket.OPEN) return;
            if (ws.bufferedAmount > 256 * 1024) {
              void cleanup(s, "网络积压过多，已停止采集");
              return;
            }
            ws.send(pcm);
          };
          s.context.createMediaStreamSource(stream).connect(s.node);
          s.node.connect(s.context.destination);
          await s.context.resume();
          $("audio").textContent =
            `音频：${s.context.sampleRate} Hz / 单声道 / PCM16 / 每包 100ms`;
          status("正在识别（最长5分钟）");
        } else if (data.type === "partial") {
          $("partial").textContent = data.text;
        } else if (data.type === "final") {
          const line = document.createElement("p");
          line.textContent = data.text;
          $("finals").append(line);
          if ($("finals").children.length > 100)
            $("finals").firstElementChild.remove();
          $("partial").textContent = "等待下一句…";
        } else if (data.type === "error") {
          await cleanup(s, data.error || "上游识别错误");
        } else if (data.type === "asr-stopped") {
          await cleanup(s, "本轮识别结束");
        }
      } catch {
        await cleanup(s, "音频初始化或服务消息处理失败");
      }
    };
  } catch (error) {
    await cleanup(s, error.message);
  }
});
$("finish").addEventListener("click", async () => {
  const s = current;
  if (!s) return;
  await stopMic(s);
  $("finish").disabled = true;
  if (s.ws?.readyState === WebSocket.OPEN) {
    s.ws.send(JSON.stringify({ type: "finish" }));
    status("已停止麦克风，等待最终结果…");
  } else await cleanup(s, "已取消尚未就绪的连接");
});
$("cancel").addEventListener("click", () => {
  if (current) void cleanup(current, "已取消");
});
window.addEventListener("pagehide", () => {
  if (current) {
    current.stream?.getTracks().forEach((track) => track.stop());
    current.ws?.close();
  }
});