import contextlib
from datetime import datetime, timedelta, timezone
import os
from pathlib import Path
import re

from fastapi import Depends, HTTPException
from fastapi.security import OAuth2PasswordBearer
from jose import JWTError, jwt
from nonebot.utils import run_sync
import psutil
import ujson as json

from zhenxun.configs.config import Config
from zhenxun.configs.path_config import DATA_PATH, IMAGE_PATH

from .base_model import SystemFolderSize, SystemStatus, User

ALGORITHM = "HS256"
ACCESS_TOKEN_EXPIRE_MINUTES = 30

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="api/login")

token_file = DATA_PATH / "web_ui" / "token.json"
token_file.parent.mkdir(parents=True, exist_ok=True)
token_data = {"token": []}
if token_file.exists():
    with contextlib.suppress(json.JSONDecodeError):
        token_data = json.load(open(token_file, encoding="utf8"))


def validate_path(path_str: str | None) -> tuple[Path | None, str | None]:
    """验证路径是否安全

    参数:
        path_str: 用户输入的路径

    返回:
        tuple[Path | None, str | None]: (验证后的路径, 错误信息)
    """
    try:
        if not path_str:
            return Path().resolve(), None

        # 1. 移除任何可能的路径遍历尝试
        path_str = re.sub(r"[\\/]\.\.[\\/]", "", path_str)

        # 2. 规范化路径并转换为绝对路径
        path = Path(path_str).resolve()

        # 3. 获取项目根目录
        root_dir = Path().resolve()

        # 4. 验证路径是否在项目根目录内
        try:
            if not path.is_relative_to(root_dir):
                return None, "访问路径超出允许范围"
        except ValueError:
            return None, "无效的路径格式"

        # 5. 验证路径是否包含任何危险字符
        if any(c in str(path) for c in ["..", "~", "*", "?", ">", "<", "|", '"']):
            return None, "路径包含非法字符"

        # 6. 验证路径长度是否合理
        return (None, "路径长度超出限制") if len(str(path)) > 4096 else (path, None)
    except Exception as e:
        return None, f"路径验证失败: {e!s}"


GROUP_HELP_PATH = DATA_PATH / "group_help"
SIMPLE_HELP_IMAGE = IMAGE_PATH / "SIMPLE_HELP.png"
SIMPLE_DETAIL_HELP_IMAGE = IMAGE_PATH / "SIMPLE_DETAIL_HELP.png"


def clear_help_image():
    """清理帮助图片"""
    if SIMPLE_HELP_IMAGE.exists():
        SIMPLE_HELP_IMAGE.unlink()
    if SIMPLE_DETAIL_HELP_IMAGE.exists():
        SIMPLE_DETAIL_HELP_IMAGE.unlink()
    for file in GROUP_HELP_PATH.iterdir():
        if file.is_file():
            file.unlink()


def get_user(uname: str) -> User | None:
    """获取账号密码

    参数:
        uname: uname

    返回:
        Optional[User]: 用户信息
    """
    username = Config.get_config("web-ui", "username")
    password = Config.get_config("web-ui", "password")
    if username and password and uname == username:
        return User(username=username, password=password)


def create_token(user: User, expires_delta: timedelta | None = None):
    """创建token

    参数:
        user: 用户信息
        expires_delta: 过期时间.
    """
    expire = datetime.now(timezone.utc) + (expires_delta or timedelta(minutes=15))
    return jwt.encode(
        claims={"sub": user.username, "exp": expire},
        key=Config.get_config("web-ui", "secret"),
        algorithm=ALGORITHM,
    )


def authentication():
    """权限验证

    异常:
        JWTError: JWTError
        HTTPException: HTTPException
    """

    # if token not in token_data["token"]:
    def inner(token: str = Depends(oauth2_scheme)):
        try:
            payload = jwt.decode(
                token, Config.get_config("web-ui", "secret"), algorithms=[ALGORITHM]
            )
            username, _ = payload.get("sub"), payload.get("exp")
            user = get_user(username)  # type: ignore
            if user is None:
                raise JWTError
        except JWTError:
            raise HTTPException(
                status_code=400, detail="登录验证失败或已失效, 踢出房间!"
            )

    return Depends(inner)


def _get_dir_size(dir_path: Path) -> float:
    """获取文件夹大小

    参数:
        dir_path: 文件夹路径
    """
    return sum(
        sum(os.path.getsize(os.path.join(root, name)) for name in files)
        for root, dirs, files in os.walk(dir_path)
    )


@run_sync
def get_system_status() -> SystemStatus:
    """获取系统信息等"""
    cpu = psutil.cpu_percent()
    memory = psutil.virtual_memory().percent
    disk = psutil.disk_usage("/").percent
    return SystemStatus(
        cpu=cpu,
        memory=memory,
        disk=disk,
        check_time=datetime.now().replace(microsecond=0),
    )


@run_sync
def get_system_disk(
    full_path: str | None,
) -> list[SystemFolderSize]:
    """获取资源文件大小等"""
    base_path = Path(full_path) if full_path else Path()
    other_size = 0
    data_list = []
    for file in os.listdir(base_path):
        f = base_path / file
        if f.is_dir():
            size = _get_dir_size(f) / 1024 / 1024
            data_list.append(
                SystemFolderSize(name=file, size=size, full_path=str(f), is_dir=True)
            )
        else:
            other_size += f.stat().st_size / 1024 / 1024
    if other_size:
        data_list.append(
            SystemFolderSize(
                name="other_file", size=other_size, full_path=full_path, is_dir=False
            )
        )
    return data_list