import os
import pytest
from datetime import datetime, timezone, timedelta
from unittest.mock import patch
from autossh_mgr.process import (
    write_pid_file, read_pid_file, delete_pid_file,
    is_process_alive, check_stale, get_status, format_uptime,
    TunnelStatus,
)


def test_write_and_read_pid_file(config_dir):
    started = datetime(2026, 5, 20, 10, 0, 0, tzinfo=timezone.utc)
    write_pid_file(config_dir, "web-service", 12345, started)
    pid, ts = read_pid_file(config_dir, "web-service")
    assert pid == 12345
    assert ts == started


def test_read_pid_file_missing(config_dir):
    assert read_pid_file(config_dir, "missing") is None


def test_delete_pid_file(config_dir):
    started = datetime.now(timezone.utc)
    write_pid_file(config_dir, "web-service", 12345, started)
    delete_pid_file(config_dir, "web-service")
    assert read_pid_file(config_dir, "web-service") is None


def test_delete_pid_file_missing_is_noop(config_dir):
    delete_pid_file(config_dir, "missing")  # must not raise


def test_is_process_alive_running():
    # os.getpid() is always alive
    assert is_process_alive(os.getpid()) is True


def test_is_process_alive_dead():
    assert is_process_alive(9999999) is False


def test_check_stale_no_pid_file(config_dir):
    assert check_stale(config_dir, "web-service") is False


def test_check_stale_running_process(config_dir):
    write_pid_file(config_dir, "web-service", os.getpid(), datetime.now(timezone.utc))
    assert check_stale(config_dir, "web-service") is False


def test_check_stale_dead_process(config_dir):
    write_pid_file(config_dir, "web-service", 9999999, datetime.now(timezone.utc))
    assert check_stale(config_dir, "web-service") is True


def test_get_status_stopped(config_dir):
    status = get_status(config_dir, "web-service")
    assert status.state == "stopped"
    assert status.pid is None
    assert status.uptime is None


def test_get_status_running(config_dir):
    write_pid_file(config_dir, "web-service", os.getpid(), datetime.now(timezone.utc))
    status = get_status(config_dir, "web-service")
    assert status.state == "running"
    assert status.pid == os.getpid()
    assert status.uptime is not None


def test_get_status_stale(config_dir):
    write_pid_file(config_dir, "web-service", 9999999, datetime.now(timezone.utc))
    status = get_status(config_dir, "web-service")
    assert status.state == "stale"
    assert status.pid == 9999999


def test_format_uptime_seconds():
    started = datetime.now(timezone.utc) - timedelta(seconds=45)
    assert format_uptime(started) == "45s"


def test_format_uptime_minutes():
    started = datetime.now(timezone.utc) - timedelta(minutes=3, seconds=15)
    assert format_uptime(started) == "3m"


def test_format_uptime_hours():
    started = datetime.now(timezone.utc) - timedelta(hours=2, minutes=30)
    assert format_uptime(started) == "2h 30m"


def test_format_uptime_days():
    started = datetime.now(timezone.utc) - timedelta(days=1, hours=5)
    assert format_uptime(started) == "1d 5h"