from types import SimpleNamespace
import wave

import numpy as np

from app.services.melo_engine import MeloEngine


class FakeMeloModel:
    def __init__(self) -> None:
        self.hps = SimpleNamespace(
            data=SimpleNamespace(
                spk2id={
                    "EN-Default": 0,
                    "EN-US": 1,
                    "EN-BR": 2,
                    "EN_INDIA": 3,
                    "EN-AU": 4,
                }
            )
        )

    def tts_to_file(
        self, text: str, speaker_id: int, output_path: str, speed: float = 1.0
    ) -> None:
        assert text
        assert speaker_id >= 0
        assert speed > 0
        pcm = (np.zeros(2400, dtype=np.float32) * 32767.0).astype(np.int16)
        with wave.open(output_path, "wb") as wav_file:
            wav_file.setnchannels(1)
            wav_file.setsampwidth(2)
            wav_file.setframerate(24000)
            wav_file.writeframes(pcm.tobytes())


def test_melo_voice_bindings_expose_en_aliases() -> None:
    engine = MeloEngine(tts_factory=FakeMeloModel)
    aliases = {row["alias"] for row in engine.list_voice_bindings()}
    assert aliases >= {"default", "us", "india"}


def test_melo_supports_expected_voices() -> None:
    engine = MeloEngine(tts_factory=FakeMeloModel)
    assert engine.supports_voice("us") is True
    assert engine.supports_voice("unknown") is False


def test_melo_synthesize_returns_waveform() -> None:
    engine = MeloEngine(tts_factory=FakeMeloModel)
    result = engine.synthesize(
        text="hello",
        voice="us",
        speed=1.0,
        quality="balanced",
        model_name="melo-en",
        lang="en",
    )
    assert result.sample_rate == 24000
    assert result.waveform.ndim == 1