"""Tests for ``laya_router.cli`` PATH / symlink helpers.

These cover the path exposure logic added so ``laya-router`` and
``laya-hook`` work from any shell without manual ``PATH`` setup.
"""

from __future__ import annotations

import os
from pathlib import Path

from laya_router.cli import (
    _apply_path_symlinks,
    _bin_link_targets,
    _remove_path_symlinks,
    _user_path_bin_dir,
    ensure_path_symlinks,
    remove_path_symlinks,
)


class _FakeSettings:
    """Minimal stand-in for ``Settings`` carrying just the paths we touch."""

    def __init__(self, router: Path, hook: Path):
        self.router_bin = router
        self.hook_bin = hook
        self.mcp_bin = router.with_name("laya-mcp")


def _make_fake_binaries(tmp_path: Path) -> tuple[Path, Path, _FakeSettings]:
    """Build two venv-style binaries on disk and return (router, hook, settings)."""
    src_dir = tmp_path / "venv_bin"
    src_dir.mkdir()
    router = src_dir / "laya-router"
    hook = src_dir / "laya-hook"
    router.write_text("#!/bin/sh\necho router\n")
    hook.write_text("#!/bin/sh\necho hook\n")
    return router, hook, _FakeSettings(router, hook)


def test_bin_link_targets_returns_both_binaries():
    from laya_router.config import load_settings

    targets = _bin_link_targets(load_settings())
    names = [name for name, _ in targets]
    assert names == ["laya-router", "laya-hook", "laya-mcp"]
    assert targets[0][1].is_file()
    assert targets[1][1].is_file()


def test_user_path_bin_dir_prefers_local_bin(monkeypatch, tmp_path):
    monkeypatch.setenv("PATH", f"{tmp_path}:/usr/bin")
    preferred = Path.home() / ".local" / "bin"
    if preferred.is_dir() and os.access(preferred, os.W_OK):
        assert _user_path_bin_dir() == preferred
    else:
        assert _user_path_bin_dir() == tmp_path


def test_user_path_bin_dir_skips_system_dirs(monkeypatch):
    # Force "no writable dir exists" by overriding to a non-existent path.
    monkeypatch.setenv("LAYA_ROUTER_BIN_DIR", "/this/path/does/not/exist")
    monkeypatch.setenv("PATH", "/usr/local/bin:/usr/bin:/bin:/sbin")
    assert _user_path_bin_dir() is None


def test_user_path_bin_dir_respects_env_override(monkeypatch, tmp_path):
    monkeypatch.setenv("LAYA_ROUTER_BIN_DIR", str(tmp_path))
    assert _user_path_bin_dir() == tmp_path


def test_user_path_bin_dir_env_override_rejects_unwritable(monkeypatch, tmp_path):
    monkeypatch.setenv("LAYA_ROUTER_BIN_DIR", "/this/path/does/not/exist")
    assert _user_path_bin_dir() is None


def test_apply_path_symlinks_creates_links(tmp_path):
    router, hook, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()

    _apply_path_symlinks(settings, bin_dir)

    assert (bin_dir / "laya-router").is_symlink()
    assert (bin_dir / "laya-router").resolve() == router.resolve()
    assert (bin_dir / "laya-hook").is_symlink()
    assert (bin_dir / "laya-hook").resolve() == hook.resolve()


def test_apply_path_symlinks_is_noop_when_correct(tmp_path):
    _, _, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()

    _apply_path_symlinks(settings, bin_dir)
    first = (bin_dir / "laya-router").lstat()

    _apply_path_symlinks(settings, bin_dir)
    second = (bin_dir / "laya-router").lstat()

    # Re-running on a correct symlink must not rewrite it.
    assert first.st_mtime_ns == second.st_mtime_ns


def test_apply_path_symlinks_repairs_wrong_target(tmp_path):
    router, _, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()
    (bin_dir / "laya-router").symlink_to("/etc/passwd")

    _apply_path_symlinks(settings, bin_dir)
    assert (bin_dir / "laya-router").resolve() == router.resolve()


def test_apply_path_symlinks_repairs_broken_symlink(tmp_path):
    router, _, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()
    (bin_dir / "laya-router").symlink_to("/nonexistent/path")

    _apply_path_symlinks(settings, bin_dir)
    assert (bin_dir / "laya-router").resolve() == router.resolve()


def test_apply_path_symlinks_skips_unrelated_file(tmp_path, capsys):
    router, _, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()
    existing = bin_dir / "laya-router"
    existing.write_text("user's binary")

    _apply_path_symlinks(settings, bin_dir)

    captured = capsys.readouterr()
    assert "已被占用" in captured.err
    # The user's file must not be clobbered.
    assert existing.read_text() == "user's binary"
    # And the other one should still get a fresh symlink.
    assert (bin_dir / "laya-hook").is_symlink()
    assert (bin_dir / "laya-router").resolve() != router.resolve()


def test_remove_path_symlinks_removes_both(tmp_path):
    _, _, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()
    _apply_path_symlinks(settings, bin_dir)
    assert (bin_dir / "laya-router").is_symlink()
    assert (bin_dir / "laya-hook").is_symlink()

    _remove_path_symlinks(settings, bin_dir)
    assert not (bin_dir / "laya-router").exists()
    assert not (bin_dir / "laya-hook").exists()


def test_remove_path_symlinks_idempotent(tmp_path):
    _, _, settings = _make_fake_binaries(tmp_path)
    bin_dir = tmp_path / "bin"
    bin_dir.mkdir()

    # No symlinks created — remove should still be safe.
    _remove_path_symlinks(settings, bin_dir)
    _remove_path_symlinks(settings, bin_dir)


def test_public_helpers_warn_when_no_writable_path(monkeypatch, capsys):
    monkeypatch.setenv("LAYA_ROUTER_BIN_DIR", "/this/path/does/not/exist")
    settings = _FakeSettings(Path("/nonexistent/router"), Path("/nonexistent/hook"))

    ensure_path_symlinks(settings)
    captured = capsys.readouterr()
    assert "没有可写的目录" in captured.err

    # remove_path_symlinks is silent in the same situation.
    remove_path_symlinks(settings)