from django.views.generic import ListView, TemplateView
from django.views.generic.edit import CreateView, UpdateView
from django.urls import reverse_lazy
from django.views.generic.detail import DetailView
from django.views.generic.edit import FormMixin
from .forms import CommentForm
from django.urls import reverse
from django.http import HttpResponseForbidden
from django.contrib.auth.mixins import LoginRequiredMixin
from django.contrib import messages
from django.shortcuts import redirect

from .models import Ticket


class HomeView(TemplateView):
    template_name = "ticketsystem/home.html"


class TicketListView(ListView):
    model = Ticket
    template_name = "ticketsystem/index.html"
    context_object_name = "tickets"
    ordering = ["-created_at"]  # neueste zuerst
    paginate_by = 10  # optional: Pagination (10 Tickets pro Seite)

    def get_queryset(self):
        queryset = super().get_queryset()
        status = self.request.GET.get("status")

        if status:
            queryset = queryset.filter(status=status)
        return queryset

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["selected_status"] = self.request.GET.get("status", "")
        return context


class TicketDetailView(FormMixin, DetailView):
    model = Ticket
    template_name = "ticketsystem/detail.html"
    context_object_name = "ticket"
    form_class = CommentForm

    def get_success_url(self):
        return reverse("detail", kwargs={"pk": self.object.pk})

    def post(self, request, *args, **kwargs):
        self.object = self.get_object()
        form = self.get_form()
        if form.is_valid():
            comment = form.save(commit=False)
            comment.ticket = self.object
            comment.author = request.user
            comment.save()
            return super().form_valid(form)
        return self.form_invalid(form)

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["form"] = self.get_form()
        return context

class TicketCreateView(CreateView):
    model = Ticket
    fields = ["title", "description", "priority", "assigned_to"]  # user & status wird automatisch gesetzt
    template_name = "ticketsystem/ticket_form.html"
    success_url = reverse_lazy("ticket-list")

    def form_valid(self, form):
        form.instance.created_by = self.request.user  # Der angemeldete User wird automatisch gesetzt
        form.instance.status = "open"  # Neues Ticket beginnt immer als "offen"
        return super().form_valid(form)

class TicketUpdateView(LoginRequiredMixin, UpdateView):
    model = Ticket
    fields = ["title", "description", "status", "priority", "assigned_to"]
    template_name = "ticketsystem/ticket_form.html"
    success_url = reverse_lazy("ticket-list")

    def dispatch(self, request, *args, **kwargs):
        ticket = self.get_object()
        user = request.user
        if user != ticket.assigned_to:
            messages.error(request, "⛔ Du darfst dieses Ticket nicht bearbeiten.")
            return redirect("detail", pk=ticket.pk)
        return super().dispatch(request, *args, **kwargs)

    def get_queryset(self):
        return Ticket.objects.all()  # Optional: Nur eigene Tickets bearbeiten lassen?