from collections import defaultdict
from django.shortcuts import render, redirect
from django.urls import reverse, reverse_lazy
from django.http import HttpResponseRedirect
from django.utils import timezone as tz
from django.utils.dates import MONTHS
from django import views
from django.contrib import messages

from .models import (Enregistrement, Etiquette, EnregistrementRecursif,)
from .forms import (EnregistrementForm, EnregistrementSpecialForm,
                    EnregistrementRecursifForm,
                    )

# Utils

def get_current_date():
    return tz.localtime(tz.now()).date()

def redirect_to_current_month(request):
    current_date = get_current_date() 
    return HttpResponseRedirect(reverse("month-view", 
                    kwargs={
                        'year': current_date.year,
                        'month': "%02d" % current_date.month,
                        }))

# Views 

class MonthView(views.generic.ListView):
    template_name = "core/index.html"

    def get(self, request, year=None, month=None, *args, **kwargs):
        self.current_date = get_current_date()
        self.year = int(year)
        self.month = int(month)
        if self.is_in_future:
            messages.warning(request, "Trying to go into the future ? Well, you've been teleported back to now...")
            return redirect_to_current_month(request)
        return super().get(request, *args, **kwargs)

    def get_queryset(self):
        """ Use custom manager method to get associated data and store it """
        qs, data = Enregistrement.objects.get_month_with_data(self.month,
                                                              self.year)
        self.data = data
        return qs

    def get_prev_month(self):
        """ Get url for previous month (no limit) """
        if self.month > 1:
            return reverse("month-view", 
                           kwargs={'year': self.year,
                                   'month': "%02d" % (self.month - 1)})
        else:
            return reverse("month-view",
                           kwargs={'year': self.year - 1,
                                   'month': 12})

    @property
    def is_in_future(self):
        return (self.year > self.current_date.year
                or (self.year == self.current_date.year
                    and self.month > self.current_date.month))
         

    def get_next_month(self):
        """ Get url for next month, but no going into the future ! """
        if self.is_in_future or (self.year == self.current_date.year
                                 and self.month == self.current_date.month):
            return None
       
        if self.month < 12:
            return reverse("month-view",
                           kwargs={'year': self.year,
                                   'month': "%02d" % (self.month + 1)})
        else:
            return reverse("month-view",
                           kwargs={'year': self.year + 1,
                                   'month': "01"})

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context['mois'], context['month'] = MONTHS[self.month], self.month
        context['annee'], context['year'] = self.year, self.year
        context['data'] = self.data
        context['prev_month_url'] = self.get_prev_month()
        context['next_month_url'] = self.get_next_month()
        return context


class EnregistrementAddView(views.generic.edit.CreateView):
    model = Enregistrement
    template_name_suffix = "_add"
    form_class = EnregistrementSpecialForm
    
    def get_initial(self):
        # Build the initial date
        date = get_current_date()
        try: date = date.replace(int(self.request.GET['year']))
        except KeyError: pass
        try: date = date.replace(date.year, int(self.request.GET['month']))
        except KeyError: pass    
        # Initials
        return {'date': date,
                'est_negatif': True,
                }
    
    def get_success_url(self):
        date = self.object.date 
        return reverse("month-view",
                       kwargs={'year': date.year,
                               'month': "%02d" % date.month})


class EnregistrementUpdateView(views.generic.edit.UpdateView):
    model = Enregistrement
    template_name_suffix = "_update_form"
    form_class = EnregistrementForm

    def get_success_url(self):
        return reverse("month-view",
                       kwargs={'year': self.object.date.year,
                               'month': "%02d" % self.object.date.month})



class EnregistrementDeleteView(views.generic.edit.DeleteView):
    model = Enregistrement
    template_name = "core/confirm_delete.html"
    
    def get_success_url(self):
        return reverse("month-view",
                       kwargs={'year': self.object.date.year,
                               'month': "%02d" % self.object.date.month})

class EtiquetteListView(views.generic.ListView):
    model = Etiquette
    template_name = "core/etiquettes.html"


class EtiquetteAddView(views.generic.edit.CreateView):
    model = Etiquette
    fields = "__all__"
    template_name_suffix = "_add_form"
    success_url = reverse_lazy('etiquette-list')


class EtiquetteUpdateView(views.generic.edit.UpdateView):
    model = Etiquette
    fields = "__all__"
    template_name_suffix = "_update_form"
    success_url = reverse_lazy('etiquette-list')


class EtiquetteDeleteView(views.generic.edit.DeleteView):
    model = Etiquette
    template_name = "core/confirm_delete.html"
    success_url = reverse_lazy("etiquette-list")


class RecursifListView(views.generic.ListView):
    model = EnregistrementRecursif
    template_name = "core/recursif_list.html"


class RecursifAddView(views.generic.edit.CreateView):
    model = EnregistrementRecursif
    form_class = EnregistrementRecursifForm
    template_name_suffix = "_add_form"
    success_url = reverse_lazy('recursif-list')


class RecursifUpdateView(views.generic.edit.UpdateView):
    model = EnregistrementRecursif
    form_class = EnregistrementRecursifForm
    template_name_suffix = "_update_form"
    success_url = reverse_lazy('recursif-list')


class RecursifDeleteView(views.generic.edit.DeleteView):
    model = EnregistrementRecursif
    template_name = "core/confirm_delete.html"
    success_url = reverse_lazy("recursif-list")