"""Tests for myagents.commands.upgrade."""

import io
from pathlib import Path

import pytest
from click.testing import CliRunner

from myagents.commands import upgrade as up_mod


@pytest.fixture()
def fake_home(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Path:
    home = tmp_path / "home"
    home.mkdir()
    monkeypatch.setattr(Path, "home", staticmethod(lambda: home))
    return home


def _make_runtime(home: Path, version: str) -> Path:
    target = home / ".xiaohe" / "runtime" / version
    target.mkdir(parents=True)
    current = target.parent / "current"
    current.unlink(missing_ok=True)
    current.symlink_to(target)
    return target


class TestParseVersion:
    def test_parses_quoted_version(self) -> None:
        assert up_mod._parse_version('BASE_URL="x"\nVERSION="v1.2.3"\n') == "v1.2.3"

    def test_returns_none_on_garbage(self) -> None:
        assert up_mod._parse_version("no version here") is None


class TestPrune:
    def test_keeps_two_newest(self, fake_home: Path) -> None:
        root = fake_home / ".xiaohe" / "runtime"
        for name in ("v1", "v2", "v3", "v4"):
            d = root / name
            d.mkdir(parents=True)
        up_mod._prune()
        remaining = sorted(p.name for p in root.iterdir())
        assert remaining == ["v3", "v4"]


class TestUpgradeCommand:
    def test_already_latest_shortcircuits(
        self, fake_home: Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        _make_runtime(fake_home, "v1.0.0")
        monkeypatch.setattr(
            up_mod, "_fetch_text", lambda *a: 'VERSION="v1.0.0"\n'
        )
        result = CliRunner().invoke(
            up_mod.upgrade_cmd, ["--user", "u", "--password", "p"]
        )
        assert result.exit_code == 0
        assert "Already up to date" in result.output

    def test_missing_runtime_errors(self, fake_home: Path) -> None:
        result = CliRunner().invoke(
            up_mod.upgrade_cmd, ["--user", "u", "--password", "p"]
        )
        assert result.exit_code != 0
        assert "install.sh" in result.output

    def test_cancelled_by_user(
        self, fake_home: Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        _make_runtime(fake_home, "v1.0.0")
        monkeypatch.setattr(
            up_mod, "_fetch_text", lambda *a: 'VERSION="v2.0.0"\n'
        )
        result = CliRunner().invoke(
            up_mod.upgrade_cmd, ["--user", "u", "--password", "p"], input="n\n"
        )
        assert result.exit_code == 0
        assert "Cancelled" in result.output


class _FakeResponse:
    def __init__(self, data: bytes) -> None:
        self.headers = {"Content-Length": str(len(data))}
        self._buf = io.BytesIO(data)

    def read(self, n: int = -1) -> bytes:
        return self._buf.read(n)

    def __enter__(self) -> "_FakeResponse":
        return self

    def __exit__(self, *args: object) -> None:
        return None


class TestFetch:
    def test_fetch_text_sends_basic_auth(
        self, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        seen: dict[str, str] = {}

        def fake_urlopen(req, timeout=0):
            seen["auth"] = req.headers["Authorization"]
            return _FakeResponse(b"hello")

        monkeypatch.setattr("urllib.request.urlopen", fake_urlopen)
        assert up_mod._fetch_text("http://x/", "u", "p") == "hello"
        assert seen["auth"].startswith("Basic ")

    def test_401_maps_to_friendly_error(
        self, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        import urllib.error

        def fake_urlopen(req, timeout=0):
            raise urllib.error.HTTPError("http://x/", 401, "Unauthorized", {}, None)

        monkeypatch.setattr("urllib.request.urlopen", fake_urlopen)
        with pytest.raises(Exception, match="401"):
            up_mod._fetch_text("http://x/", "u", "p")

    def test_download_writes_file(
        self, tmp_path: Path, monkeypatch: pytest.MonkeyPatch
    ) -> None:
        payload = b"x" * 100_000
        monkeypatch.setattr(
            "urllib.request.urlopen",
            lambda req, timeout=0: _FakeResponse(payload),
        )
        dest = tmp_path / "out.tar.gz"
        up_mod._download("http://x/f", "u", "p", dest)
        assert dest.read_bytes() == payload