import sys
from types import SimpleNamespace

import pytest

import signspeak.tts as tts_module


class FakeTTS:
    def generate_custom_voice(self, text, language, speaker, instruct):
        assert text == "Hello."
        assert language == "English"
        assert speaker == "Ryan"
        assert instruct == "Speak clearly."
        return [[0.0, 0.1, 0.0]], 24000


def test_generate_tts_uses_model_and_writes_file(monkeypatch, tmp_path):
    writes = []

    def fake_write(path, data, sample_rate):
        writes.append((path, data, sample_rate))

    monkeypatch.setattr(tts_module, "get_tts_model", lambda: FakeTTS())
    monkeypatch.setattr(tts_module.tempfile, "gettempdir", lambda: str(tmp_path))
    monkeypatch.setitem(sys.modules, "soundfile", SimpleNamespace(write=fake_write))

    output_path = tts_module.generate_tts("Hello.", "English", "Ryan", "Speak clearly.")

    assert output_path.startswith(str(tmp_path))
    assert writes == [(output_path, [0.0, 0.1, 0.0], 24000)]


def test_generate_tts_rejects_empty_text():
    with pytest.raises(ValueError):
        tts_module.generate_tts("", "English", "Ryan", "Speak clearly.")