from __future__ import annotations

import subprocess
from pathlib import Path

import pytest

from pyro_mcp.vm_network import NetworkConfig, TapNetworkManager


def test_tap_network_manager_allocation_disabled_by_default(
    monkeypatch: pytest.MonkeyPatch,
) -> None:
    monkeypatch.delenv("PYRO_VM_ENABLE_NETWORK", raising=False)
    manager = TapNetworkManager()
    config = manager.allocate("abcdef123456")
    assert manager.enabled is False
    assert config.tap_name == "pyroabcdef12"
    assert config.guest_ip.startswith("172.29.")
    metadata = manager.to_metadata(config)
    assert metadata["network_enabled"] == "false"


def test_tap_network_manager_network_info() -> None:
    manager = TapNetworkManager(enabled=False)
    config = NetworkConfig(
        vm_id="abcdef123456",
        tap_name="pyroabcdef12",
        guest_ip="172.29.100.2",
        gateway_ip="172.29.100.1",
        subnet_cidr="172.29.100.0/24",
        mac_address="06:00:ab:cd:ef:12",
    )
    info = manager.network_info(config)
    assert info["tap_name"] == "pyroabcdef12"
    assert info["outbound_connectivity_expected"] is False


def test_tap_network_manager_enabled_runs_host_commands() -> None:
    commands: list[list[str]] = []

    def runner(command: list[str]) -> subprocess.CompletedProcess[str]:
        commands.append(command)
        return subprocess.CompletedProcess(command, 0, "", "")

    manager = TapNetworkManager(enabled=True, runner=runner)
    config = manager.allocate("abcdef123456")
    manager.cleanup(config)
    assert commands[0][:4] == ["ip", "tuntap", "add", "dev"]
    assert commands[-1][:3] in (["ip", "link", "del"], ["nft", "delete", "table"])


def test_tap_network_manager_missing_host_support(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.setattr(Path, "exists", lambda self: False if str(self) == "/dev/net/tun" else True)
    manager = TapNetworkManager(
        enabled=True,
        runner=lambda command: subprocess.CompletedProcess(command, 0, "", ""),
    )
    with pytest.raises(RuntimeError, match="/dev/net/tun"):
        manager.allocate("abcdef123456")