"""Speech-to-text via faster-whisper."""
from __future__ import annotations

import logging
import os
from typing import Tuple

from src.translator import translate

logger = logging.getLogger(__name__)

# Lazy whisper model loader
_whisper_model = None


def _get_model():
    global _whisper_model
    if _whisper_model is None:
        from faster_whisper import WhisperModel
        model_size = os.environ.get("RYUGAKU_WHISPER_MODEL", "small")
        device = "cpu" if os.environ.get("RYUGAKU_FORCE_CPU") == "1" else "cuda"
        logger.info("Loading faster-whisper model=%s device=%s", model_size, device)
        _whisper_model = WhisperModel(model_size, device=device, compute_type="float16" if device == "cuda" else "int8")
    return _whisper_model


def transcribe_and_translate(audio_path: str) -> Tuple[str, str, str]:
    """Transcribe an audio file and translate the Japanese text.

    Returns (transcript, translation, status).
    """
    if not audio_path or not os.path.exists(audio_path):
        return "", "", "No audio file provided"

    try:
        model = _get_model()
        segments, info = model.transcribe(audio_path, language="ja", beam_size=5)
        text_parts = [segment.text for segment in segments]
        transcript = " ".join(text_parts).strip()
        if not transcript:
            return "", "", "No speech detected"
        translation, _ = translate(transcript)
        return transcript, translation, ""
    except Exception as e:
        logger.exception("STT failed")
        return "", "", f"STT error: {e}"