// 语音转文字：使用 OpenAI Whisper API 或其他兼容服务
const WHISPER_API_KEY = process.env.WHISPER_API_KEY || process.env.DEEPSEEK_API_KEY || "";
const WHISPER_API_BASE = process.env.WHISPER_API_BASE || process.env.DEEPSEEK_BASE_URL || "https://api.openai.com/v1";
const WHISPER_MODEL = process.env.WHISPER_MODEL || "whisper-1";

export async function transcribeAudio(audioBuffer: ArrayBuffer, filename: string): Promise<string> {
  if (!WHISPER_API_KEY) {
    throw new Error("未配置语音转文字 API（设置 WHISPER_API_KEY 或 DEEPSEEK_API_KEY）");
  }

  const formData = new FormData();
  const blob = new Blob([audioBuffer], { type: "audio/ogg" });
  formData.append("file", blob, filename);
  formData.append("model", WHISPER_MODEL);
  formData.append("language", "zh");

  const url = `${WHISPER_API_BASE}/audio/transcriptions`;
  const res = await fetch(url, {
    method: "POST",
    headers: {
      "Authorization": `Bearer ${WHISPER_API_KEY}`,
    },
    body: formData,
  });

  if (!res.ok) {
    const err = await res.text();
    throw new Error(`语音转文字失败: ${res.status} ${err}`);
  }

  const data = await res.json() as { text?: string };
  return data.text || "";
}