import calendar
import functools
import json

from django.core.exceptions import ObjectDoesNotExist
from django.http import HttpResponse, HttpResponseForbidden
from django.utils.decorators import method_decorator
from django.views.decorators.csrf import csrf_exempt
from django.views.decorators.http import require_http_methods
from oauth2_provider.models import get_access_token_model
from oauth2_provider.oauth2_backends import OAuthLibCore
from oauth2_provider.views import ClientProtectedScopedResourceView
from oauthlib.oauth2 import Server

# from apps.gooyal_oauth2.validators import IntrospectOAuth2Validator


# @method_decorator(csrf_exempt, name="dispatch")
# class IntrospectTokenView(ClientProtectedScopedResourceView):
#     """
#     Implements an endpoint for token introspection based
#     on RFC 7662 https://tools.ietf.org/html/rfc7662
#
#     To access this view the request must pass a OAuth2 Bearer Token
#     which is allowed to access the scope `introspection`.
#     """
#     required_scopes = ["introspection"]
#
#     @staticmethod
#     def get_token_response(token_value=None):
#         try:
#             token = get_access_token_model().objects.get(token=token_value)
#         except ObjectDoesNotExist:
#             return HttpResponse(
#                 content=json.dumps({"active": False}),
#                 status=401,
#                 content_type="application/json"
#             )
#         else:
#             if token.is_valid():
#                 data = {
#                     "active": True,
#                     "scope": token.scope,
#                     "exp": int(calendar.timegm(token.expires.timetuple())),
#                 }
#                 if token.application:
#                     data["client_id"] = token.application.client_id
#                 if token.user:
#                     data["username"] = token.user.get_username()
#                 return HttpResponse(content=json.dumps(data), status=200, content_type="application/json")
#             else:
#                 return HttpResponse(content=json.dumps({
#                     "active": False,
#                 }), status=200, content_type="application/json")
#
#     def get(self, request, *args, **kwargs):
#         """
#         Get the token from the URL parameters.
#         URL: https://example.com/introspect?token=mF_9.B5f-4.1JqM
#
#         :param request:
#         :param args:
#         :param kwargs:
#         :return:
#         """
#         return self.get_token_response(request.GET.get("token", None))
#
#     def post(self, request, *args, **kwargs):
#         """
#         Get the token from the body form parameters.
#         Body: token=mF_9.B5f-4.1JqM
#
#         :param request:
#         :param args:
#         :param kwargs:
#         :return:
#         """
#         return self.get_token_response(request.POST.get("token", None))


# def protected_resource(scopes=None):
#     """
#     Implementation of protected_resource decorator that saves the client on the
#     request for the view function to use.
#
#     Cribbed from django-oauth-toolkit.
#     """
#     _scopes = scopes or []
#
#     def decorator(view_func):
#         @functools.wraps(view_func)
#         def _validate(request, *args, **kwargs):
#             validator = IntrospectOAuth2Validator()
#             core = OAuthLibCore(Server(validator))
#             valid, oauthlib_req = core.verify_request(request, scopes=_scopes)
#             if valid:
#                 request.client = oauthlib_req.client
#                 request.resource_owner = oauthlib_req.user
#                 return view_func(request, *args, **kwargs)
#             return HttpResponseForbidden()
#
#         return _validate
#
#     return decorator
#
#
# @require_http_methods(['GET', 'POST'])
# @csrf_exempt
# @protected_resource(scopes=['introspection'])
# def introspect_token(request):
#     """
#     Version of the introspection view protected by a regular scope instead of
#     read-write scopes.
#
#     Also allows for the required scope to be changed using a setting.
#     """
#     if request.method == 'GET':
#         token = request.GET.get("token", None)
#     else:
#         token = request.POST.get("token", None)
#     return IntrospectTokenView.get_token_response(token)


# @require_POST
# @csrf_exempt
# @protected_resource(scopes=[settings.REGISTER_SCOPE_SCOPE])
# def register_scope(request):
#     """
#     Implements an endpoint for registering a scope.
#     """
#     #  Get the scope data from the request body
#     scope_data = json.loads(request.body) if request.body else {}
#     try:
#         try:
#             #  If a scope with the given name already exists, find it
#             scope = Scope.objects.get(name=scope_data['name'])
#         except Scope.DoesNotExist:
#             #  If no scope with the given name exists, create it
#             _ = Scope.objects.create(
#                 application=request.client,
#                 name=scope_data['name'],
#                 description=scope_data['description'],
#                 is_default=scope_data.get('is_default', False)
#             )
#             #  Respond with a 201 Created
#             return HttpResponse(status=201)
#     except KeyError as exc:
#         #  A key missing in the data should be reported as a bad request
#         return HttpResponse(
#             status=400,
#             content="'{}' must be given in request data".format(exc.args[0]),
#             content_type='text/plain'
#         )
#     #  If the scope does exist, check that the current application is the
#     #  owner of the scope before updating it
#     if scope.application and scope.application == request.client:
#         scope.description = scope_data['description']
#         scope.is_default = scope_data.get('is_default', False)
#         scope.save()
#         return HttpResponse(status=200)
#     else:
#         return HttpResponse(status=403)