"""passbook OAuth2 Views"""
from urllib.parse import urlencode

from django.contrib import messages
from django.contrib.auth.mixins import LoginRequiredMixin
from django.shortcuts import get_object_or_404, redirect, reverse
from django.utils.translation import ugettext as _
from oauth2_provider.views.base import AuthorizationView
from structlog import get_logger

from passbook.audit.models import Event, EventAction
from passbook.core.models import Application
from passbook.core.views.access import AccessMixin
from passbook.core.views.utils import LoadingView, PermissionDeniedView
from passbook.providers.oauth.models import OAuth2Provider

LOGGER = get_logger()


class PassbookAuthorizationLoadingView(LoginRequiredMixin, LoadingView):
    """Show loading view for permission checks"""

    title = _("Checking permissions...")

    def get_url(self):
        querystring = urlencode(self.request.GET)
        return (
            reverse("passbook_providers_oauth:oauth2-ok-authorize") + "?" + querystring
        )


class OAuthPermissionDenied(PermissionDeniedView):
    """Show permission denied view"""


class PassbookAuthorizationView(AccessMixin, AuthorizationView):
    """Custom OAuth2 Authorization View which checks policies, etc"""

    _application = None

    def _inject_response_type(self):
        """Inject response_type into querystring if not set"""
        LOGGER.debug("response_type not set, defaulting to 'code'")
        querystring = urlencode(self.request.GET)
        querystring += "&response_type=code"
        return redirect(
            reverse("passbook_providers_oauth:oauth2-ok-authorize") + "?" + querystring
        )

    def dispatch(self, request, *args, **kwargs):
        """Update OAuth2Provider's skip_authorization state"""
        # Get client_id to get provider, so we can update skip_authorization field
        client_id = request.GET.get("client_id")
        provider = get_object_or_404(OAuth2Provider, client_id=client_id)
        try:
            application = self.provider_to_application(provider)
        except Application.DoesNotExist:
            return redirect("passbook_providers_oauth:oauth2-permission-denied")
        # Update field here so oauth-toolkit does work for us
        provider.skip_authorization = application.skip_authorization
        provider.save()
        self._application = application
        # Check permissions
        passing, policy_messages = self.user_has_access(self._application, request.user)
        if not passing:
            for policy_message in policy_messages:
                messages.error(request, policy_message)
            return redirect("passbook_providers_oauth:oauth2-permission-denied")
        # Some clients don't pass response_type, so we default to code
        if "response_type" not in request.GET:
            return self._inject_response_type()
        actual_response = super().dispatch(request, *args, **kwargs)
        if actual_response.status_code == 400:
            LOGGER.debug(request.GET.get("redirect_uri"))
        return actual_response

    def form_valid(self, form):
        # User has clicked on "Authorize"
        Event.new(
            EventAction.AUTHORIZE_APPLICATION, authorized_application=self._application,
        ).from_http(self.request)
        LOGGER.debug(
            "User authorized Application",
            user=self.request.user,
            application=self._application,
        )
        return super().form_valid(form)