import { EventEmitter } from 'node:events';
import { acquireQvac, releaseQvac, loadAuxiliaryModel, unloadAuxiliaryModel, qvacSdk, withQvacMaster, assertSdkVersion } from './qvac-master.js';

export class QvacVoiceAdapter extends EventEmitter {
  constructor({ asrModel = process.env.JARVIS_ASR_MODEL || 'WHISPER_TINY', ttsModel = process.env.JARVIS_TTS_MODEL || 'TTS_EN_SUPERTONIC_Q8_0' } = {}) {
    super(); this.asrModel = asrModel; this.ttsModel = ttsModel; this.asrId = null; this.ttsId = null; this.asrSession = null; this.acquired = false;
  }

  async start() {
    if (this.acquired) return;
    assertSdkVersion();
    await acquireQvac(); this.acquired = true;
    try {
      this.asrId = await loadAuxiliaryModel(this.asrModel, { vadModelSrc: 'VAD_SILERO_5_1_2', audio_format: 's16le', language: 'en', no_timestamps: true, vad_params: { threshold: 0.6, min_speech_duration_ms: 300, min_silence_duration_ms: 700, max_speech_duration_s: 15, speech_pad_ms: 200 } }, 'whisper');
      this.ttsId = await loadAuxiliaryModel(this.ttsModel, { ttsEngine: 'supertonic', language: 'en', voice: 'F1', ttsSpeed: 1.05, ttsNumInferenceSteps: 5 }, 'tts');
    } catch (error) { await this.stop(); throw error; }
  }

  writeAudio(chunk) { this.asrSession?.write(Buffer.from(chunk)); }
  async transcribeAudio(audio) {
    const sdk = await qvacSdk();
    return withQvacMaster(async () => {
      const session = await sdk.transcribeStream({ modelId: this.asrId, emitVadEvents: true });
      session.write(Buffer.from(audio)); session.end();
      const parts = [];
      for await (const event of session) parts.push(typeof event === 'string' ? event : event?.text || '');
      return parts.join(' ').trim();
    });
  }
  async *transcripts() { if (!this.asrSession) throw new Error('voice adapter is not started'); yield* this.asrSession; }
  endAudio() { this.asrSession?.end(); }

  async speak(text) {
    const sdk = await qvacSdk();
    const samples = await withQvacMaster(async () => {
      const result = sdk.textToSpeech({ modelId: this.ttsId, text: String(text), inputType: 'text', stream: false });
      return result.buffer;
    });
    return { samples: Int16Array.from(samples), sampleRate: 44_100 };
  }

  async stop() {
    try { this.asrSession?.destroy?.(); } catch {}
    this.asrSession = null;
    if (this.ttsId) await unloadAuxiliaryModel(this.ttsId).catch(() => {});
    if (this.asrId) await unloadAuxiliaryModel(this.asrId).catch(() => {});
    this.ttsId = this.asrId = null;
    if (this.acquired) { this.acquired = false; releaseQvac(); }
  }
}