"""Supertonic 합성 워커 (전용 venv에서 실행).

- ONNX 런타임 기반, torch 불필요, 모델 ~260MB
- 다국어(31개) 지원. 한국어는 lang="ko", 자동감지는 lang="na"
- 프리셋 음성 10종(M1~M5, F1~F5)
- 속도(speed) 네이티브, 피치(pitch)는 librosa 후처리
"""
from __future__ import annotations

import io

import shutil

import numpy as np
import soundfile as sf

try:
    import librosa
except Exception:  # pragma: no cover
    librosa = None

try:
    import pyrubberband as prb
except Exception:  # pragma: no cover
    prb = None


def time_stretch(audio: np.ndarray, sr: int, rate: float) -> np.ndarray:
    """피치 보존 배속(Rubberband R3 → librosa 폴백). rate>1 = 빠르게."""
    if abs(rate - 1.0) < 1e-3:
        return audio
    audio = np.asarray(audio, dtype=np.float32)
    if prb is not None and shutil.which("rubberband"):
        try:
            return np.asarray(
                prb.time_stretch(audio, sr, rate, rbargs={"--engine": "finer"}),
                dtype=np.float32,
            )
        except Exception:
            try:
                return np.asarray(prb.time_stretch(audio, sr, rate), dtype=np.float32)
            except Exception:
                pass
    if librosa is not None:
        try:
            return librosa.effects.time_stretch(audio, rate=rate).astype(np.float32)
        except Exception:
            pass
    return audio

from fastapi import FastAPI
from fastapi.responses import Response
from pydantic import BaseModel

from supertonic import TTS

VOICES = ["M1", "M2", "M3", "M4", "M5", "F1", "F2", "F3", "F4", "F5"]
SR = 44100

_tts = None
_styles: dict = {}


def get_tts() -> TTS:
    global _tts
    if _tts is None:
        _tts = TTS(auto_download=True)
    return _tts


def get_style(name: str):
    if name not in _styles:
        _styles[name] = get_tts().get_voice_style(voice_name=name)
    return _styles[name]


app = FastAPI(title="Supertonic Worker")


class SynthReq(BaseModel):
    text: str
    voice: str = "F1"
    lang: str = "ko"
    speed: float = 1.0
    pitch: float = 0.0


@app.on_event("startup")
def _startup() -> None:
    get_tts()
    get_style("F1")


@app.get("/health")
def health() -> dict:
    get_tts()
    return {"status": "ok", "voices": VOICES, "sr": SR}


@app.post("/synth")
def synth(req: SynthReq) -> Response:
    text = (req.text or "").strip()
    if not text:
        return Response(content="empty text", status_code=400)

    tts = get_tts()
    voice = req.voice if req.voice in VOICES else "F1"
    style = get_style(voice)
    lang = req.lang if req.lang in ("ko", "na", "en", "ja", "zh") else "ko"
    speed = float(max(0.5, min(2.0, req.speed)))
    pitch = float(max(-12.0, min(12.0, req.pitch)))

    # 자연 속도로 합성 후 피치 보존 배속(고배속에서도 목소리 안 뭉개짐)
    wav, _dur = tts.synthesize(text, voice_style=style, lang=lang, speed=1.0)
    audio = np.asarray(wav).reshape(-1).astype(np.float32)

    if abs(speed - 1.0) > 1e-3:
        audio = time_stretch(audio, SR, speed)
    if abs(pitch) > 1e-3 and librosa is not None:
        audio = librosa.effects.pitch_shift(audio, sr=SR, n_steps=pitch)

    buf = io.BytesIO()
    sf.write(buf, audio, SR, format="WAV", subtype="PCM_16")
    buf.seek(0)
    return Response(content=buf.read(), media_type="audio/wav")