#!/usr/bin/env python3
# -*- coding: utf-8 -*-
from asgiref.sync import sync_to_async
from fastapi import Response
from starlette.background import BackgroundTask
from starlette.datastructures import UploadFile
from starlette.middleware.base import BaseHTTPMiddleware
from starlette.requests import Request

from backend.app.common.enums import OperaLogCipherType
from backend.app.common.log import log
from backend.app.core.conf import settings
from backend.app.schemas.opera_log import CreateOperaLogParam
from backend.app.services.opera_log_service import OperaLogService
from backend.app.utils.encrypt import AESCipher, ItsDCipher, Md5Cipher
from backend.app.utils.request_parse import parse_ip_info, parse_user_agent_info
from backend.app.utils.timezone import timezone


class OperaLogMiddleware(BaseHTTPMiddleware):
    """操作日志中间件"""

    async def dispatch(self, request: Request, call_next) -> Response:
        # 排除记录白名单
        path = request.url.path
        if path in settings.OPERA_LOG_EXCLUDE or not path.startswith(f'{settings.API_V1_STR}'):
            return await call_next(request)

        # 请求解析
        user_agent, device, os, browser = await parse_user_agent_info(request)
        ip, country, region, city = await parse_ip_info(request)
        try:
            # 此信息依赖于 jwt 中间件
            username = request.user.username
        except AttributeError:
            username = None
        method = request.method
        router = request.scope.get('route')
        summary = getattr(router, 'summary', None) or ''
        args = await self.get_request_args(request)
        args = await self.desensitization(args)

        # 设置附加请求信息
        request.state.ip = ip
        request.state.country = country
        request.state.region = region
        request.state.city = city
        request.state.user_agent = user_agent
        request.state.os = os
        request.state.browser = browser
        request.state.device = device

        # 执行请求
        start_time = timezone.now()
        code, msg, status, err, response = await self.execute_request(request, call_next)
        end_time = timezone.now()
        cost_time = (end_time - start_time).total_seconds() * 1000.0

        # 日志创建
        opera_log_in = CreateOperaLogParam(
            username=username,
            method=method,
            title=summary,
            path=path,
            ip=ip,
            country=country,
            region=region,
            city=city,
            user_agent=user_agent,
            os=os,
            browser=browser,
            device=device,
            args=args,
            status=status,
            code=code,
            msg=msg,
            cost_time=cost_time,
            opera_time=start_time,
        )
        back = BackgroundTask(OperaLogService.create, obj_in=opera_log_in)
        await back()

        # 错误抛出
        if err:
            raise err from None

        return response

    async def execute_request(self, request: Request, call_next) -> tuple:
        """执行请求"""
        err = None
        response = None
        try:
            response = await call_next(request)
            code, msg, status = await self.request_exception_handler(request)
        except Exception as e:
            log.exception(e)
            # code 处理包含 SQLAlchemy 和 Pydantic
            code = getattr(e, 'code', None) or 500
            msg = getattr(e, 'msg', None) or 'Internal Server Error'
            status = 0
            err = e

        return str(code), msg, status, err, response

    @staticmethod
    @sync_to_async
    def request_exception_handler(request: Request) -> tuple:
        """请求异常处理器"""
        code = 200
        msg = 'Success'
        status = 1
        try:
            http_exception = request.state.__request_http_exception__
        except AttributeError:
            pass
        else:
            code = http_exception.get('code', 500)
            msg = http_exception.get('msg', 'Internal Server Error')
            status = 0
        try:
            validation_exception = request.state.__request_validation_exception__
        except AttributeError:
            pass
        else:
            code = validation_exception.get('code', 400)
            msg = validation_exception.get('msg', 'Bad Request')
            status = 0
        return code, msg, status

    @staticmethod
    async def get_request_args(request: Request) -> dict:
        """获取请求参数"""
        args = dict(request.query_params)
        args.update(request.path_params)
        # Tip: .body() 必须在 .form() 之前获取
        # https://github.com/encode/starlette/discussions/1933
        body_data = await request.body()
        form_data = await request.form()
        if len(form_data) > 0:
            args.update({k: v.filename if isinstance(v, UploadFile) else v for k, v in form_data.items()})
        else:
            if body_data:
                json_data = await request.json()
                if not isinstance(json_data, dict):
                    json_data = {
                        f'{type(json_data)}_to_dict_data': json_data.decode('utf-8')
                        if isinstance(json_data, bytes)
                        else json_data
                    }
                args.update(json_data)
        return args

    @staticmethod
    @sync_to_async
    def desensitization(args: dict) -> dict | None:
        """
        脱敏处理

        :param args:
        :return:
        """
        if not args:
            args = None
        else:
            match settings.OPERA_LOG_ENCRYPT:
                case OperaLogCipherType.aes:
                    for key in args.keys():
                        if key in settings.OPERA_LOG_ENCRYPT_INCLUDE:
                            args[key] = (AESCipher(settings.OPERA_LOG_ENCRYPT_SECRET_KEY).encrypt(args[key])).hex()
                case OperaLogCipherType.md5:
                    for key in args.keys():
                        if key in settings.OPERA_LOG_ENCRYPT_INCLUDE:
                            args[key] = Md5Cipher.encrypt(args[key])
                case OperaLogCipherType.itsdangerous:
                    for key in args.keys():
                        if key in settings.OPERA_LOG_ENCRYPT_INCLUDE:
                            args[key] = ItsDCipher(settings.OPERA_LOG_ENCRYPT_SECRET_KEY).encrypt(args[key])
                case OperaLogCipherType.plan:
                    pass
                case _:
                    for key in args.keys():
                        if key in settings.OPERA_LOG_ENCRYPT_INCLUDE:
                            args[key] = '******'
        return args