from pathlib import Path
from typing import Tuple

import docker

from app.core.config import settings
from app.core.event import eventmanager, Event
from app.log import logger
from app.schemas import ConfigChangeEventData
from app.schemas.types import EventType
from app.utils.system import SystemUtils


class SystemHelper:
    """
    系统工具类，提供系统相关的操作和判断
    """

    __system_flag_file = "/var/log/nginx/__moviepilot__"

    @eventmanager.register(EventType.ConfigChanged)
    def handle_config_changed(self, event: Event):
        """
        处理配置变更事件，更新日志设置
        :param event: 事件对象
        """
        if not event:
            return
        event_data: ConfigChangeEventData = event.event_data
        if event_data.key not in ['DEBUG', 'LOG_LEVEL', 'LOG_MAX_FILE_SIZE', 'LOG_BACKUP_COUNT',
                                  'LOG_FILE_FORMAT', 'LOG_CONSOLE_FORMAT']:
            return
        logger.info("配置变更，更新日志设置...")
        logger.update_loggers()

    @staticmethod
    def can_restart() -> bool:
        """
        判断是否可以内部重启
        """
        return (
                Path("/var/run/docker.sock").exists()
                or settings.DOCKER_CLIENT_API != "tcp://127.0.0.1:38379"
        )

    @staticmethod
    def _get_container_id() -> str:
        """
        获取当前容器ID
        """
        container_id = None
        try:
            with open("/proc/self/mountinfo", "r") as f:
                data = f.read()
                index_resolv_conf = data.find("resolv.conf")
                if index_resolv_conf != -1:
                    index_second_slash = data.rfind("/", 0, index_resolv_conf)
                    index_first_slash = data.rfind("/", 0, index_second_slash) + 1
                    container_id = data[index_first_slash:index_second_slash]
                    if len(container_id) < 20:
                        index_resolv_conf = data.find("/sys/fs/cgroup/devices")
                        if index_resolv_conf != -1:
                            index_second_slash = data.rfind(" ", 0, index_resolv_conf)
                            index_first_slash = (
                                    data.rfind("/", 0, index_second_slash) + 1
                            )
                            container_id = data[index_first_slash:index_second_slash]
        except Exception as e:
            logger.debug(f"获取容器ID失败: {str(e)}")
        return container_id.strip() if container_id else None

    @staticmethod
    def restart() -> Tuple[bool, str]:
        """
        执行Docker重启操作
        """
        if not SystemUtils.is_docker():
            return False, "非Docker环境，无法重启！"

        logger.info("正在重启容器...")
        return SystemHelper._docker_api_restart()

    @staticmethod
    def _docker_api_restart() -> Tuple[bool, str]:
        """
        使用Docker API重启容器，并尝试优雅停止
        """
        try:
            # 创建 Docker 客户端
            client = docker.DockerClient(base_url=settings.DOCKER_CLIENT_API)
            container_id = SystemHelper._get_container_id()
            if not container_id:
                return False, "获取容器ID失败！"
            # 重启容器
            client.containers.get(container_id).restart()
            return True, ""
        except Exception as docker_err:
            return False, f"重启时发生错误：{str(docker_err)}"

    def set_system_modified(self):
        """
        设置系统已修改标志
        """
        try:
            if SystemUtils.is_docker():
                Path(self.__system_flag_file).touch(exist_ok=True)
        except Exception as e:
            print(f"设置系统修改标志失败: {str(e)}")

    def is_system_reset(self) -> bool:
        """
        检查系统是否已被重置
        :return: 如果系统已重置，返回 True；否则返回 False
        """
        if SystemUtils.is_docker():
            return not Path(self.__system_flag_file).exists()
        return False