"""The `hermetic_environment` fixture, tested as the guard it is.

Everything else in this suite depends on that fixture without ever mentioning
it - which is the point, and also the risk: a fixture nothing asserts against
can be weakened, or lose a variable, and every test stays green until the
suite next runs on a machine that has the variable set. So the guard gets its
own tests, and `config.default_author()` gets the coverage the fixture makes
writable for the first time: what it returns on a machine that knows nobody.
"""
import os
import subprocess
from pathlib import Path

import pytest

import chemenu.config as config
from chemenu.tests.conftest import _GIT_ENV, _WIKITOOL_ENV


def test_home_points_into_the_test_s_own_tmp_path(tmp_path: Path, hermetic_environment: Path):
    assert hermetic_environment == tmp_path / "home"
    assert Path(os.environ["HOME"]) == hermetic_environment
    assert hermetic_environment.is_dir()
    assert not list(hermetic_environment.iterdir())


def test_the_tool_s_own_environment_is_cleared():
    for name in _WIKITOOL_ENV:
        assert name not in os.environ, f"{name} leaked into the test environment"
    for name in _GIT_ENV:
        assert name not in os.environ, f"{name} leaked into the test environment"


def test_tracing_stays_on_and_redirected(isolated_trace_dir: Path):
    """`hermetic_environment` clears WIKI_TRACE, `isolated_trace_dir` sets
    WIKI_TRACE_DIR - and the ordering between the two autouse fixtures must
    leave both in that state, or the telemetry tests break."""
    assert "WIKI_TRACE" not in os.environ  # i.e. the default, which is on
    assert Path(os.environ["WIKI_TRACE_DIR"]) == isolated_trace_dir


def test_git_sees_no_configuration_from_this_machine(tmp_path: Path):
    """The failure behind Gitea #8, asserted directly: outside a repository
    with a local identity, `git config user.name` must answer nothing."""
    result = subprocess.run(
        ["git", "config", "user.name"],
        cwd=tmp_path, capture_output=True, text=True, check=False,
    )
    assert result.stdout.strip() == "", (
        "global or system git configuration is still visible to the suite"
    )


def test_default_author_is_none_without_an_identity(tmp_path: Path,
                                                    monkeypatch: pytest.MonkeyPatch):
    """The branch that used to be untestable: no WIKI_AUTHOR, no git identity
    anywhere, so `new source` has nothing to stamp and must say so."""
    monkeypatch.setattr(config, "ROOT", tmp_path)
    assert config.default_author() is None


def test_default_author_reads_a_local_git_identity(tmp_path: Path,
                                                   monkeypatch: pytest.MonkeyPatch):
    subprocess.run(["git", "init", "-q", "-b", "main"], cwd=tmp_path, check=True)
    subprocess.run(["git", "config", "user.name", "Local Identity"], cwd=tmp_path, check=True)
    monkeypatch.setattr(config, "ROOT", tmp_path)
    assert config.default_author() == "Local Identity"


def test_wiki_author_overrides_the_git_identity(tmp_path: Path,
                                                monkeypatch: pytest.MonkeyPatch):
    subprocess.run(["git", "init", "-q", "-b", "main"], cwd=tmp_path, check=True)
    subprocess.run(["git", "config", "user.name", "Local Identity"], cwd=tmp_path, check=True)
    monkeypatch.setattr(config, "ROOT", tmp_path)
    monkeypatch.setenv("WIKI_AUTHOR", "Env Override")
    assert config.default_author() == "Env Override"


def test_kb_dir_repoints_the_configured_root_at_its_own_tree(kb_dir: Path, tmp_path: Path):
    """The other half of the isolation, and the one `kb_dir` was missing until
    Gitea #44: a fixture that builds a corpus but leaves `config.ROOT` on the
    real checkout hands every `config.KB_DIR` lookup the developer's own wiki -
    which is how a test overwrote the repository's `.wikitool-kb.json`."""
    assert config.ROOT == tmp_path
    assert config.KB_DIR == kb_dir


def test_raw_dir_repoints_the_configured_root_at_its_own_tree(raw_dir: Path, tmp_path: Path):
    assert config.ROOT == tmp_path
    assert config.RAW_DIR == raw_dir


def test_both_corpus_fixtures_keep_the_shipped_type_specs_reachable(kb_dir: Path):
    """Repointing `ROOT` moves `TYPES_DIR` with it, so the repoint has to be
    paired with `use_shipped_type_specs()` or no page type resolves at all."""
    assert (config.TYPES_DIR / "entity.md").is_file()