"""Shared test fixtures."""

from __future__ import annotations

from pathlib import Path
from unittest.mock import MagicMock

import numpy as np
import pytest
import soundfile as sf


@pytest.fixture
def tmp_output_dir(tmp_path: Path) -> Path:
    """Provide a temporary output directory."""
    d = tmp_path / "output"
    d.mkdir()
    return d


@pytest.fixture
def test_audio_path(tmp_path: Path) -> Path:
    """Generate a small synthetic WAV file (~1 second, 44100 Hz, mono)."""
    path = tmp_path / "test_tone.wav"
    sr = 44100
    duration = 1.0
    t = np.linspace(0, duration, int(sr * duration), endpoint=False)
    audio = (0.5 * np.sin(2 * np.pi * 440 * t)).astype(np.float32)
    sf.write(str(path), audio, sr)
    return path


@pytest.fixture
def mock_separator(mocker, tmp_output_dir: Path):
    """Mock audio_separator.separator.Separator for 2-stem output."""
    mock_cls = mocker.patch("audio_separator.separator.Separator")
    instance = MagicMock()
    mock_cls.return_value = instance

    def fake_separate(input_path):
        stem = Path(input_path).stem
        files = []
        for label in ["Vocals", "Instrumental"]:
            out = tmp_output_dir / f"{stem}_{label}.wav"
            out.touch()
            files.append(str(out))
        return files

    instance.separate.side_effect = fake_separate
    instance.load_model.return_value = None

    return instance


@pytest.fixture
def mock_separator_4stem(mocker, tmp_output_dir: Path):
    """Mock separator producing 4-stem outputs."""
    mock_cls = mocker.patch("audio_separator.separator.Separator")
    instance = MagicMock()
    mock_cls.return_value = instance

    def fake_separate(input_path):
        stem = Path(input_path).stem
        files = []
        for label in ["Vocals", "Drums", "Bass", "Other"]:
            out = tmp_output_dir / f"{stem}_{label}.wav"
            out.touch()
            files.append(str(out))
        return files

    instance.separate.side_effect = fake_separate
    instance.load_model.return_value = None

    return instance


@pytest.fixture
def env_settings(monkeypatch, tmp_output_dir: Path):
    """Set environment variables for testing config."""
    monkeypatch.setenv("STEMSPLITTER_OUTPUT_DIR", str(tmp_output_dir))
    monkeypatch.setenv("STEMSPLITTER_LOG_LEVEL", "DEBUG")
    monkeypatch.setenv("STEMSPLITTER_OUTPUT_FORMAT", "WAV")