# settings.py
SECRET_KEY = 'abcde1234',
JWT_ALGORITHM = 'HS256'

# user/views.py
import json
from datetime import datetime, timdelta
from django.conf import settings
from django.http import JsonResponse
from django.views import View

import bcrypt
import jwt
from .models import User
from token_utils import user_token

class UserSignInView(View):
    def post(self, request):
        try:
            data = json.loads(request.body)
            username = data['username']
            pw_input = data['password']
            user = User.objects.filter(username=username).first()

            if user is None:
                return JsonResponse({"message": "INVALID_USERNAME"}, status=401)
            if bcrypt.checkpw(pw_input.encode('utf-8'),
                              user.password.encode('utf-8')):
                key = settings.SECRET_KEY
                algorithm = settings.JWT_ALGORITHM
                token = jwt.encode(
                    {
                        'iss': 'me',
                        'id': user.id,
                        'exp': datetime.utcnow() + timedelta(days=14)
                    }, key, algorithm=algorithm).decode('utf-8')

                response = JsonResponse(
                    {
                        'message': 'SUCCESS'
                    }, status=200
                )

                # 當(dāng)使用本地/會(huì)話存儲(chǔ)而不是Cookie時(shí)，只需在JsonResponse中發(fā)送令牌
                if data.get('remember_me') is not None:
                    max_age = 14*24*60*60 # 14 days
                    expires = datetime.strftime(
                        datetime.utcnow() + timedelta(seconds=max_age),
                        "%Y-%m-%d %H:%M:%S"
                    )
                    response.set_cookie(
                        'token',
                        token,
                        max_age=max_age,
                        expires=expires,
                        httponly=True
                    )
                    return response
            return JsonResponse({"message": "WRONG_PASSWORD"}, status=401)

        except KeyError as e:
            return JsonResponse({'message': f'KEY_ERROR: {e}'}, status=400)
        except ValueError as e:
            return JsonResponse({'message': f'VALUE_ERROR: {e}'}, status=400)

# token_utils.py
import json
from django.conf import settings
from django.http import JsonResponse
import jwt
from user.models import User

def user_token(func):
    def wrapper(self, request, *args, **kwargs):
        try:
            token = request.COOKIES.get('token')
            # token = request.headers.get('token')

            key = settings.SECRET_KEY
            algorithm = settings.JWT_ALGORITHM

            if token is None:
                return JsonResponse({"message": "INVALID_TOKEN"}, status=401)

            decode = jwt.decode(token, key, algorithm=algorithm)
            request.user = User.objects.get(id=decode['id'])

        except jwt.ExpiredSignatureError:
            return JsonResponse({"message": "EXPIRED_TOKEN"}, status=400)
        return func(self, request, *args, **kwargs)
    return wrapper