import sys
from io import StringIO
from pathlib import Path

from l4d2host.instances import initialize_instance


def test_initialize_writes_files(tmp_path: Path) -> None:
    spec = tmp_path / "spec.yaml"
    spec.write_text("port: 27015\noverlays: [a,b]\nconfig: ['sv_consistency 1']\n")

    initialize_instance("alpha", spec, root=tmp_path)

    assert (tmp_path / "instances/alpha/instance.env").exists()
    assert (tmp_path / "instances/alpha/server.cfg").exists()


def test_empty_config_writes_empty_server_cfg(tmp_path: Path) -> None:
    spec = tmp_path / "spec.yaml"
    spec.write_text("port: 27015\n")

    initialize_instance("alpha", spec, root=tmp_path)

    assert (tmp_path / "instances/alpha/server.cfg").read_text() == ""


def test_initialize_uses_configured_left4me_root(tmp_path: Path, monkeypatch) -> None:
    monkeypatch.setenv("LEFT4ME_ROOT", str(tmp_path))
    spec = tmp_path / "spec.yaml"
    spec.write_text("port: 27015\noverlays: [standard]\n")

    initialize_instance("alpha", spec)

    env = (tmp_path / "instances/alpha/instance.env").read_text()
    assert f"L4D2_LOWERDIRS={tmp_path}/overlays/standard:{tmp_path}/installation" in env


def test_initialize_instance_emits_steps(tmp_path: Path) -> None:
    spec = tmp_path / "spec.yaml"
    spec.write_text("port: 27015\noverlays: [standard]\n")

    steps: list[str] = []
    initialize_instance("alpha", spec, root=tmp_path, on_stdout=steps.append)

    assert steps == [
        "Step: creating instance directories...",
        "Step: writing instance.env...",
        "Step: writing server.cfg...",
        "Step: initialization complete.",
    ]