"""Unit tests for daemon PID file management."""

from __future__ import annotations

import os
from pathlib import Path

import pytest

from pyra.daemon.pid import PidFile, PidFileError, resolve_pid_path


def test_write_creates_file(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    p.write()
    assert (tmp_path / "daemon.pid").exists()
    assert int((tmp_path / "daemon.pid").read_text().strip()) == os.getpid()


def test_read_returns_none_when_absent(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    assert p.read() is None


def test_read_returns_pid_when_present(tmp_path: Path) -> None:
    pid_file = tmp_path / "daemon.pid"
    pid_file.write_text("12345")
    p = PidFile(pid_file)
    assert p.read() == 12345


def test_read_returns_none_on_bad_content(tmp_path: Path) -> None:
    pid_file = tmp_path / "daemon.pid"
    pid_file.write_text("not-a-number")
    p = PidFile(pid_file)
    assert p.read() is None


def test_is_stale_false_for_self(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    p.write()
    assert not p.is_stale()


def test_is_stale_true_for_dead_pid(tmp_path: Path) -> None:
    pid_file = tmp_path / "daemon.pid"
    pid_file.write_text("999999999")  # unrealistically large PID
    p = PidFile(pid_file)
    assert p.is_stale()


def test_is_stale_false_when_file_absent(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    assert not p.is_stale()


def test_remove_deletes_file(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    p.write()
    p.remove()
    assert not (tmp_path / "daemon.pid").exists()


def test_remove_is_idempotent(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    p.remove()  # must not raise


def test_context_manager_writes_and_removes(tmp_path: Path) -> None:
    pid_file = tmp_path / "daemon.pid"
    p = PidFile(pid_file)
    with p:
        assert pid_file.exists()
        assert int(pid_file.read_text().strip()) == os.getpid()
    assert not pid_file.exists()


def test_write_raises_when_live_pid_exists(tmp_path: Path) -> None:
    p = PidFile(tmp_path / "daemon.pid")
    p.write()  # writes self PID (which is alive)
    p2 = PidFile(tmp_path / "daemon.pid")
    with pytest.raises(PidFileError):
        p2.write()


def test_write_succeeds_over_stale_pid(tmp_path: Path) -> None:
    pid_file = tmp_path / "daemon.pid"
    pid_file.write_text("999999999")  # stale
    p = PidFile(pid_file)
    p.write()  # should not raise
    assert int(pid_file.read_text().strip()) == os.getpid()


def test_resolve_pid_path_expands_tilde() -> None:
    result = resolve_pid_path("~/.pyra/daemon.pid")
    assert not str(result).startswith("~")
    assert result.is_absolute()


def test_resolve_pid_path_absolute_unchanged(tmp_path: Path) -> None:
    path = tmp_path / "daemon.pid"
    result = resolve_pid_path(str(path))
    assert result == path