from __future__ import annotations

import subprocess
import sys
from pathlib import Path

import pytest

CLI_COMMANDS = ["mouse-collect", "mouse-train", "mouse-visualize"]


@pytest.mark.parametrize("command", CLI_COMMANDS)
def test_cli_help(command: str) -> None:
    """Every CLI must respond to --help with exit 0 and an argparse usage line."""
    result = subprocess.run(
        [command, "--help"], capture_output=True, text=True, check=False,
    )
    assert result.returncode == 0, result.stderr
    assert "usage:" in result.stdout


def test_visualize_no_show_produces_png(tmp_path: Path) -> None:
    save_path = tmp_path / "out.png"
    result = subprocess.run(
        [
            "mouse-visualize", "--no-show", "--seed", "1",
            "--n-trajectories", "3", "--n-interp", "20",
            "--save", str(save_path),
        ],
        capture_output=True, text=True, check=False,
    )
    assert result.returncode == 0, result.stderr
    assert save_path.exists()
    assert save_path.stat().st_size > 1000


def test_visualize_module_invocation(tmp_path: Path) -> None:
    """The module is also runnable via `python -m mouse_control.visualize`."""
    save_path = tmp_path / "out.png"
    result = subprocess.run(
        [
            sys.executable, "-m", "mouse_control.visualize",
            "--no-show", "--seed", "2", "--n-trajectories", "2",
            "--save", str(save_path),
        ],
        capture_output=True, text=True, check=False,
    )
    assert result.returncode == 0, result.stderr
    assert save_path.exists()