"""The host-browser sandbox.

Two independent gates, both in :mod:`services.device_service`:

* ``_is_allowed`` — is the logical path under one of ``ALLOWED_BROWSE_ROOTS``?
* ``_real_root`` — maps the logical path into the container's view, and refuses
  anything landing inside StackPilot's own ``DATA_DIR``.

The second gate exists because the API deliberately never hands out what lives
there (agent tokens come back as a bool, destination secrets come back masked),
so the file browser must not be the way around that — for admins either.
"""
from __future__ import annotations

import pytest


@pytest.fixture
def sandbox(monkeypatch):
    """Pin the sandbox settings so the tests don't depend on deployment config."""
    from config import settings
    from services import device_service

    monkeypatch.setattr(settings, "DATA_DIR", "/data", raising=False)
    monkeypatch.setattr(settings, "HOST_ROOT_PREFIX", "", raising=False)
    monkeypatch.setattr(
        settings, "ALLOWED_BROWSE_ROOTS", ["/mnt", "/media", "/srv", "/opt", "/home"],
        raising=False,
    )
    return device_service


def _refused(mod, path: str) -> bool:
    """Whether the sandbox rejects a path, by either gate."""
    if not mod._is_allowed(path):
        return True
    try:
        mod._real_root(path)
        return False
    except mod.BrowseError:
        return True


@pytest.mark.parametrize(
    "path",
    [
        "/data",
        "/data/stackpilot.db",
        "/data/secret_key",
        "/opt/../data/stackpilot.db",  # traversal into it
    ],
)
def test_own_data_dir_is_refused(sandbox, path):
    assert _refused(sandbox, path), f"{path} would expose StackPilot's own database"


@pytest.mark.parametrize(
    "path",
    ["/etc/shadow", "/root/.ssh/id_rsa", "/var/run/docker.sock", "/proc/self/environ"],
)
def test_paths_outside_the_roots_are_refused(sandbox, path):
    assert _refused(sandbox, path)


@pytest.mark.parametrize(
    "path",
    ["/opt", "/opt/stacks/jellyfin/.env", "/srv/media", "/mnt", "/home/someone"],
)
def test_allowed_roots_stay_reachable(sandbox, path):
    assert not _refused(sandbox, path), f"{path} should still be browsable"


def test_slash_in_the_roots_opens_everything_except_the_data_dir(sandbox, monkeypatch):
    """A "/" entry switches the sandbox off — that is why it is not a default.

    It still must not open StackPilot's own data directory, since that gate is
    independent of the root list.
    """
    from config import settings

    monkeypatch.setattr(settings, "ALLOWED_BROWSE_ROOTS", ["/"], raising=False)
    assert not _refused(sandbox, "/etc/shadow")
    assert _refused(sandbox, "/data/stackpilot.db")


def test_host_root_prefix_maps_paths_into_the_container(sandbox, monkeypatch):
    """With the host mounted at a prefix, /data is a host path, not our own.

    The container's own ``/data`` becomes unreachable by any logical path in
    this mode, so the refusal correctly does not apply.
    """
    from config import settings

    monkeypatch.setattr(settings, "HOST_ROOT_PREFIX", "/host_root", raising=False)
    monkeypatch.setattr(settings, "ALLOWED_BROWSE_ROOTS", ["/data", "/opt"], raising=False)
    assert sandbox._real_root("/data/foo") == "/host_root/data/foo"


def test_file_service_shares_the_same_gate(sandbox):
    """``file_service`` must not have its own, weaker path check."""
    from services import file_service

    with pytest.raises(file_service.BrowseError):
        file_service._safe_real("/data/stackpilot.db")
    with pytest.raises(file_service.BrowseError):
        file_service._safe_real("/etc/shadow")
    assert file_service._safe_real("/opt/stacks") == "/opt/stacks"


@pytest.mark.parametrize("name", ["..", ".", "a/b", "a\\b", ""])
def test_child_rejects_anything_but_a_single_component(sandbox, name):
    """Upload and rename build paths through ``_child``; traversal dies here."""
    from services import file_service

    with pytest.raises(file_service.BrowseError):
        file_service._child("/opt", name)