from __future__ import annotations

from pathlib import Path


def _project_root() -> Path:
    # This test file lives in `<root>/tests/`.
    return Path(__file__).resolve().parents[1]


def _render_dashboard_service(*, vt: int = 1) -> str:
    template_path = (
        _project_root()
        / "infrastructure/roles/dashboard/templates/dashboard.service.j2"
    )
    template = template_path.read_text(encoding="utf-8")

    # Keep this test dependency-free (no Jinja2 import required).
    return (
        template.replace("{{ dashboard_vt }}", str(vt))
        .replace("{{ dashboard_script_dest }}", "/usr/local/bin/dashboard.sh")
        .replace("{{ dashboard_user }}", "pi")
    )


def test_dashboard_service_is_safe_for_multi_user_target() -> None:
    rendered = _render_dashboard_service(vt=1)

    # Avoid an ordering cycle with the target that wants the service.
    assert "After=multi-user.target" not in rendered
    assert "Wants=multi-user.target" not in rendered
    assert "WantedBy=multi-user.target" in rendered


def test_dashboard_service_attaches_to_a_vt_and_passes_vt_to_script() -> None:
    rendered = _render_dashboard_service(vt=1)

    assert "TTYPath=/dev/tty1" in rendered
    assert "StandardInput=tty" in rendered
    assert "Environment=DASHBOARD_VT=1" in rendered


def test_dashboard_service_does_not_use_su_by_default() -> None:
    rendered = _render_dashboard_service(vt=1)
    assert "su -l" not in rendered


def test_dashboard_script_passes_vt_and_keeptty_to_xorg() -> None:
    script_path = _project_root() / "tools/dashboard.sh"
    script = script_path.read_text(encoding="utf-8")

    assert "DASHBOARD_VT" in script
    assert "vt${DASHBOARD_VT}" in script
    assert "-keeptty" in script