from typing import TYPE_CHECKING

from django.contrib.auth import views as auth_views
from django.contrib.auth.hashers import make_password
from django.contrib.auth.mixins import LoginRequiredMixin, UserPassesTestMixin
from django.contrib.auth.models import Permission
from django.contrib.messages.views import SuccessMessageMixin
from django.db.models import QuerySet
from django.urls import reverse, reverse_lazy
from django.utils.translation import gettext_lazy as _
from django.views.generic import CreateView, FormView, ListView, TemplateView

from elections.typing import AuthenticatedRequest

from .forms import ElectionAuthForm, PwdUserForm, UserAdminForm
from .utils import generate_password

if TYPE_CHECKING:
    from elections.typing import User
else:
    from django.contrib.auth import get_user_model
    User = get_user_model()


# #############################################################################
#  Mixin to restrict access to staff members
# #############################################################################


class StaffMemberMixin(UserPassesTestMixin):
    """
    Mixin permettant de restreindre l'accès aux membres `staff`, si la personne
    n'est pas connectée, renvoie sur la page d'authentification
    """

    request: AuthenticatedRequest

    def test_func(self):
        return self.request.user.is_active and self.request.user.is_staff


# #############################################################################
#  Election Specific Login
# #############################################################################


class ElectionLoginView(auth_views.LoginView):
    template_name = "auth/election_login.html"
    authentication_form = ElectionAuthForm

    def get_initial(self):
        return {"election_id": self.kwargs.get("election_id")}

    def get_context_data(self, **kwargs):
        kwargs.update({"election_id": self.kwargs.get("election_id")})
        return super().get_context_data(**kwargs)


# #############################################################################
#  Admin Panel
# #############################################################################


class AdminPanelView(StaffMemberMixin, TemplateView):
    template_name = "auth/admin-panel.html"


# #############################################################################
#  Creation of Password Accounts
# #############################################################################


class CreatePwdAccount(StaffMemberMixin, SuccessMessageMixin, CreateView):
    model = User
    form_class = PwdUserForm
    template_name = "auth/create-user.html"
    success_url = reverse_lazy("auth.admin")
    success_message = _("Compte créé avec succès")

    def form_valid(self, form):
        # On enregistre un mot de passe aléatoire
        form.instance.password = make_password(generate_password(32))

        return super().form_valid(form)


# #############################################################################
#  List of password and CAS users
# #############################################################################


class AccountListView(StaffMemberMixin, ListView):
    model = User
    template_name = "auth/account-list.html"

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)
        qs: QuerySet = self.get_queryset()  # pyright: ignore

        ctx["cas_users"] = qs.filter(username__startswith="cas__")
        ctx["pwd_users"] = qs.filter(username__startswith="pwd__")
        ctx["e_manager"] = User.objects.with_perm(
            Permission.objects.get(codename="election_admin"),
            backend="shared.auth.backends.PwdBackend",
        )
        ctx["f_manager"] = User.objects.with_perm(
            Permission.objects.get(codename="faq_admin"),
            backend="shared.auth.backends.PwdBackend",
        )

        return ctx


# #############################################################################
#  Permission management
# #############################################################################


class PermissionManagementView(StaffMemberMixin, SuccessMessageMixin, FormView):
    form_class = UserAdminForm
    template_name = "auth/permission-management.html"
    success_message = _("Permissions modifiées avec succès !")

    def get_context_data(self, **kwargs):
        kwargs.update({"username": self.request.GET.get("user", None)})
        return super().get_context_data(**kwargs)

    def get_initial(self):
        username = self.request.GET.get("user", None)
        if username is not None:
            user = User.objects.filter(username=username).first()

            if user is not None:
                return {
                    "username": username,
                    "full_admin": user.is_staff,
                    "election_admin": user.has_perm("elections.election_admin"),
                    "faq_admin": user.has_perm("faqs.faq_admin"),
                }

        return {}

    def get_success_url(self):
        return reverse("auth.permissions") + f"?user={self.user}"

    def form_valid(self, form):
        user = User.objects.get(username=form.cleaned_data["username"])
        self.user = user.username

        # Kadenios admin
        user.is_staff = form.cleaned_data["full_admin"]

        # Election admin
        election_perm = Permission.objects.get(codename="election_admin")
        if form.cleaned_data["election_admin"]:
            election_perm.user_set.add(user)  # pyright: ignore
        else:
            election_perm.user_set.remove(user)  # pyright: ignore

        # FAQ admin
        faq_perm = Permission.objects.get(codename="faq_admin")
        if form.cleaned_data["faq_admin"]:
            faq_perm.user_set.add(user)  # pyright: ignore
        else:
            faq_perm.user_set.remove(user)  # pyright: ignore

        user.save()
        return super().form_valid(form)


# #############################################################################
#  List of special accounts
# #############################################################################


class AdminAccountsView(LoginRequiredMixin, TemplateView):
    template_name = "auth/admin-accounts.html"

    def get_context_data(self, **kwargs):
        ctx = super().get_context_data(**kwargs)

        ctx["admin"] = User.objects.filter(is_staff=True)
        ctx["e_manager"] = User.objects.with_perm(
            Permission.objects.get(codename="election_admin"),
            backend="shared.auth.backends.PwdBackend",
        )
        ctx["f_manager"] = User.objects.with_perm(
            Permission.objects.get(codename="faq_admin"),
            backend="shared.auth.backends.PwdBackend",
        )
        return ctx