const PIPER_LENGTH_SCALE_BY_QUALITY = {
  easy: '1.15',
  medium: '1.0',
  hard: '0.9',
};

function normalizeOpenAiBaseUrl(url) {
  const value = String(url || '').trim();
  if (!value) return 'https://api.openai.com/v1';
  return value.replace(/\/+$/, '');
}

export function isTextToSpeechConfigured(entrySettings) {
  const cfg = entrySettings?.tools?.textToSpeech || {};
  const provider = String(cfg.provider || 'browser');
  if (provider === 'browser') return true;
  if (provider === 'piper-http') return !!String(cfg.piperBaseUrl || '').trim();
  if (provider === 'openai') return !!String(cfg.apiKey || '').trim();
  return false;
}

export async function speakTextBySettings(text, entrySettings) {
  const value = String(text || '').trim();
  if (!value) return;

  const cfg = entrySettings?.tools?.textToSpeech || {};
  const provider = String(cfg.provider || 'browser');

  if (provider === 'browser') {
    const utt = new SpeechSynthesisUtterance(value);
    utt.lang = 'ru-RU';
    const selected = String(cfg.voice || '').trim();
    if (selected) {
      const voice = window.speechSynthesis.getVoices().find((v) => v.name === selected);
      if (voice) utt.voice = voice;
    }
    window.speechSynthesis.speak(utt);
    return;
  }

  if (provider === 'piper-http') {
    const baseUrl = String(cfg.piperBaseUrl || '').trim().replace(/\/+$/, '');
    if (!baseUrl) throw new Error('Не указан адрес Piper HTTP.');
    const quality = String(cfg.quality || 'medium').toLowerCase();
    const voice = String(cfg.voice || '').trim();
    const lengthScale = PIPER_LENGTH_SCALE_BY_QUALITY[quality] || PIPER_LENGTH_SCALE_BY_QUALITY.medium;
    const resp = await fetch(`${baseUrl}/api/tts`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        text: value,
        voice,
        quality,
        length_scale: lengthScale,
      }),
    });
    if (!resp.ok) throw new Error(`Piper HTTP недоступен (${resp.status}).`);
    const blob = await resp.blob();
    const audioUrl = URL.createObjectURL(blob);
    const audio = new Audio(audioUrl);
    await audio.play();
    window.setTimeout(() => URL.revokeObjectURL(audioUrl), 30000);
    return;
  }

  if (provider === 'openai') {
    const apiKey = String(cfg.apiKey || '').trim();
    if (!apiKey) throw new Error('Не заполнен API key для OpenAI TTS.');
    const model = String(cfg.model || '').trim() || 'gpt-4o-mini-tts';
    const baseUrl = normalizeOpenAiBaseUrl(cfg.externalBaseUrl || cfg.baseUrl || 'https://api.openai.com/v1');
    const voice = String(cfg.voice || '').trim() || 'alloy';
    const resp = await fetch(`${baseUrl}/audio/speech`, {
      method: 'POST',
      headers: {
        Authorization: `Bearer ${apiKey}`,
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        model,
        voice,
        input: value,
        format: 'mp3',
      }),
    });
    if (!resp.ok) throw new Error(`OpenAI TTS недоступен (${resp.status}).`);
    const blob = await resp.blob();
    const audioUrl = URL.createObjectURL(blob);
    const audio = new Audio(audioUrl);
    await audio.play();
    window.setTimeout(() => URL.revokeObjectURL(audioUrl), 30000);
    return;
  }

  throw new Error('Неизвестный провайдер озвучки.');
}