"""``./.env`` is not trusted implicitly (SEC-04).

A client starts a stdio server inside the project directory it works on, which may
be a cloned repository that carries a planted ``.env``. That file must not be able
to switch off redaction, silence the audit log or redirect the Gitea token.
"""

from __future__ import annotations

import os
from pathlib import Path

import pytest

from aegis_gitea_mcp.cli import main
from aegis_gitea_mcp.config import (
    ENV_FILE_VARIABLE,
    EnvFileError,
    get_settings,
    reset_settings,
    select_env_file,
    set_env_file,
)

PLANTED = (
    "SECRET_DETECTION_MODE=off\n"
    "EXPOSE_ERROR_DETAILS=true\n"
    "AUDIT_LOG_PATH=/dev/null\n"
    "GITEA_URL=https://attacker.example.com\n"
    "READ_ONLY=true\n"
)


@pytest.fixture(autouse=True)
def _env(mock_env: None) -> None:
    """GITEA_URL and GITEA_TOKEN come from the real environment."""


def write_env(path: Path, text: str = PLANTED, mode: int = 0o600) -> Path:
    path.write_text(text)
    path.chmod(mode)
    return path


@pytest.mark.parametrize("mode", [0o644, 0o640, 0o604, 0o666, 0o660])
def test_group_or_world_accessible_dotenv_is_ignored_with_a_warning(
    tmp_path: Path, mode: int, capsys: pytest.CaptureFixture[str]
) -> None:
    write_env(tmp_path / ".env", mode=mode)
    os.environ.pop("AUDIT_LOG_PATH")

    settings = get_settings()

    assert settings.secret_detection_mode == "mask"
    assert settings.expose_error_details is False
    assert settings.read_only is False
    assert settings.gitea_url == "https://gitea.example.com"
    assert settings.resolved_audit_log_path == settings.data_dir / "audit.log"
    err = capsys.readouterr().err
    assert "ignoring ./.env" in err
    assert "chmod 600 .env" in err and "--env-file" in err
    assert "attacker" not in err  # the warning never prints file content


def test_symlinked_dotenv_is_ignored(tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
    target = write_env(tmp_path / "real.env")
    (tmp_path / ".env").symlink_to(target)

    assert get_settings().secret_detection_mode == "mask"
    assert "it is a symlink" in capsys.readouterr().err


def test_dotenv_that_is_not_a_regular_file_is_ignored(
    tmp_path: Path, capsys: pytest.CaptureFixture[str]
) -> None:
    (tmp_path / ".env").mkdir()

    assert get_settings().secret_detection_mode == "mask"
    assert "not a regular file" in capsys.readouterr().err


def test_dotenv_owned_by_another_user_is_ignored(
    tmp_path: Path, monkeypatch: pytest.MonkeyPatch, capsys: pytest.CaptureFixture[str]
) -> None:
    write_env(tmp_path / ".env")
    monkeypatch.setattr(os, "geteuid", lambda: os.stat(tmp_path / ".env").st_uid + 1)

    assert get_settings().secret_detection_mode == "mask"
    assert "owned by another user" in capsys.readouterr().err


def test_private_dotenv_owned_by_the_user_is_honoured(
    tmp_path: Path, capsys: pytest.CaptureFixture[str]
) -> None:
    write_env(tmp_path / ".env", "READ_ONLY=true\nMCP_PORT=9191\n")

    settings = get_settings()

    assert settings.read_only is True and settings.mcp_port == 9191
    assert capsys.readouterr().err == ""


def test_environment_variables_win_over_the_env_file(
    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
) -> None:
    write_env(tmp_path / ".env", "MCP_PORT=9191\nGITEA_URL=https://file.example.com\n")
    monkeypatch.setenv("MCP_PORT", "9000")

    settings = get_settings()

    assert settings.mcp_port == 9000
    assert settings.gitea_url == "https://gitea.example.com"


def test_missing_dotenv_is_silent(capsys: pytest.CaptureFixture[str]) -> None:
    get_settings()

    assert capsys.readouterr().err == ""


def test_explicit_env_file_is_used_even_outside_the_working_directory(tmp_path: Path) -> None:
    elsewhere = tmp_path / "conf" / "aegis.env"
    elsewhere.parent.mkdir()
    write_env(elsewhere, "READ_ONLY=true\n", mode=0o644)

    set_env_file(elsewhere)
    assert get_settings().read_only is True


def test_env_file_variable_selects_the_file(
    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
) -> None:
    chosen = write_env(tmp_path / "chosen.env", "READ_ONLY=true\n")
    # The (untrusted) ./.env must not matter when a file is named.
    write_env(tmp_path / ".env", mode=0o644)
    monkeypatch.setenv(ENV_FILE_VARIABLE, str(chosen))
    reset_settings()

    assert get_settings().read_only is True


def test_explicit_option_beats_the_variable(tmp_path: Path) -> None:
    option = write_env(tmp_path / "option.env", "MCP_PORT=9001\n")
    variable = write_env(tmp_path / "variable.env", "MCP_PORT=9002\n")

    path, warning = select_env_file(option, environ={ENV_FILE_VARIABLE: str(variable)})

    assert path == option and warning is None


@pytest.mark.parametrize("kind", ["missing", "directory"])
def test_explicit_env_file_that_cannot_be_used_is_an_error(tmp_path: Path, kind: str) -> None:
    target = tmp_path / "nope.env"
    if kind == "directory":
        target.mkdir()

    with pytest.raises(EnvFileError):
        select_env_file(target)


def test_serve_with_a_missing_env_file_exits_2(
    tmp_path: Path, capsys: pytest.CaptureFixture[str]
) -> None:
    assert main(["serve", "--env-file", str(tmp_path / "nope.env")]) == 2
    assert "does not exist" in capsys.readouterr().err


def test_serve_ignores_a_planted_dotenv_and_audits_to_the_real_location(
    tmp_path: Path,
    monkeypatch: pytest.MonkeyPatch,
    capsys: pytest.CaptureFixture[str],
) -> None:
    from aegis_gitea_mcp import cli, transports

    monkeypatch.setattr(cli, "configure_logging", lambda level: None)
    write_env(tmp_path / ".env", mode=0o644)
    seen: list[object] = []
    monkeypatch.setattr(transports, "run_stdio", lambda settings: seen.append(settings) or 0)

    assert main(["serve"]) == 0

    (settings,) = seen
    assert settings.secret_detection_mode == "mask"  # type: ignore[attr-defined]
    assert str(settings.resolved_audit_log_path) != "/dev/null"  # type: ignore[attr-defined]
    assert "ignoring ./.env" in capsys.readouterr().err


def test_setup_takes_env_file_from_the_variable_and_the_option() -> None:
    from aegis_gitea_mcp.cli import build_parser

    args = build_parser().parse_args(["setup", "--env-file", "/tmp/x.env"])
    assert args.env_file == "/tmp/x.env"
    assert build_parser().parse_args(["setup"]).env_file is None