# kokoro_utils.py
import os
import tempfile
import soundfile as sf
from kokoro_onnx import Kokoro

# Resolve paths relative to project root
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
MODEL_PATH = os.path.join(BASE_DIR, "kokoro-v1.0.onnx")
VOICES_PATH = os.path.join(BASE_DIR, "voices-v1.0.bin")

_kokoro_instance = None

def get_kokoro_engine():
    global _kokoro_instance
    if _kokoro_instance is None:
        if os.path.exists(MODEL_PATH) and os.path.exists(VOICES_PATH):
            _kokoro_instance = Kokoro(MODEL_PATH, VOICES_PATH)
    return _kokoro_instance

def generate_local_speech(text: str, voice_name: str = "af_bella", speed: float = 1.0) -> str:
    """
    Synthesizes speech locally using Kokoro and saves to a temp file, 
    returning the path to the generated audio file with correct language routing.
    """
    engine = get_kokoro_engine()
    if not engine:
        raise FileNotFoundError(
            f"Kokoro model files not found at root directory.\nExpected:\n- {MODEL_PATH}\n- {VOICES_PATH}"
        )

    # Route language code explicitly based on voice prefix
    if voice_name.startswith("es") or voice_name.startswith("ef") or voice_name.startswith("em"):
        lang_code = "es"
    else:
        lang_code = "en-us"

    samples, sample_rate = engine.create(
        text, 
        voice=voice_name, 
        speed=speed, 
        lang=lang_code
    )

    temp_file = os.path.join(tempfile.gettempdir(), "kokoro_review_audio.wav")
    sf.write(temp_file, samples, sample_rate)
    return temp_file