from datetime import timedelta

from django.conf import settings
from django.contrib import messages
from django.contrib.auth.mixins import LoginRequiredMixin
from django.contrib.sitemaps import Sitemap
from django.core.mail import mail_admins, send_mass_mail
from django.db.models import Count
from django.forms import formset_factory
from django.shortcuts import redirect, render
from django.template.loader import render_to_string
from django.urls import reverse
from django.views.generic import RedirectView, UpdateView, TemplateView, View

from accounts.models import EmailUser
from home.models import ActivityList, InterludesActivity, InterludesParticipant
from home.forms import ActivityForm, BaseActivityFormSet, InscriptionForm
from site_settings.models import SiteSettings
from shared.views import CSVWriteView, SuperuserRequiredMixin


# ==============================
# Site static pages
# ==============================


class HomeView(TemplateView):
	"""Vue pour la page d'acceuil"""
	template_name = "home.html"


class ActivityView(TemplateView):
	"""Vue pour la liste des activités"""
	template_name = "activites.html"

	def get_context_data(self, **kwargs):
		"""ajoute la liste des activités au contexte"""
		context = super(ActivityView, self).get_context_data(**kwargs)
		settings = SiteSettings.load()
		context['activities'] = InterludesActivity.objects.filter(display=True).order_by("title")
		context['planning'] = InterludesActivity.objects.filter(on_planning=True).order_by("title")
		context['friday'] = settings.date_start.day
		context['saturday'] = (settings.date_start + timedelta(days=1)).day
		context['sunday'] = (settings.date_start + timedelta(days=2)).day
		return context


class FAQView(TemplateView):
	"""Vue pour la FAQ"""
	template_name = "faq.html"


# ==============================
# Registration
# ==============================


class RegisterClosed(TemplateView):
	"""Vue pour quand les inscriptions ne sont pas ouvertes"""
	template_name = "inscription/closed.html"

class RegisterSignIn(TemplateView):
	"""Vue affichée quand les inscriptions sont ouverte mais
	l'utilisateur n'est pas connecté"""
	template_name = "inscription/signin.html"

class RegisterUpdateView(LoginRequiredMixin, TemplateView):
	"""Vue pour s'inscrire et modifier son inscription"""
	template_name = "inscription/form.html"
	form_class = InscriptionForm
	formset_class = formset_factory(form=ActivityForm, extra=3, formset=BaseActivityFormSet)

	@staticmethod
	def get_activities(participant):
		activities = ActivityList.objects.filter(participant=participant).order_by("priority")
		return [{"activity": act.activity} for act in activities]

	@staticmethod
	def set_activities(participant, formset):
		# delete old activites
		ActivityList.objects.filter(participant=participant).delete()

		priority = 0
		for form in formset:
			data = form.cleaned_data
			if data:
				activity = data["activity"]
				ActivityList(priority=priority, participant=participant, activity=activity).save()
				priority += 1

	def get(self, request, *args, **kwargs):
		participant = request.user.profile
		activities = self.get_activities(participant)
		form = self.form_class(instance=participant)
		formset = self.formset_class(initial=activities)
		context = {"form": form, "formset": formset}
		return render(request, self.template_name, context)

	def post(self, request, *args, **kwargs):
		form = self.form_class(request.POST, instance=request.user.profile)
		formset = self.formset_class(request.POST)
		if not (form.is_valid() and formset.is_valid()):
			context = {"form": form, "formset": formset}
			return render(request, self.template_name, context)

		form.save()
		self.set_activities(request.user.profile, formset)

		messages.success(request, "Votre inscription a bien été enregistrée")
		return redirect("accounts:profile", permanent=False)

class RegisterView(View):
	"""Vue pour l'inscription
	repartie sur les vue RegisterClosed, RegisterSignIn et RegisterUpdateView"""
	def dispatch(self, request, *args, **kwargs):
		settings = SiteSettings.load()
		if not settings.inscriptions_open:
			return RegisterClosed.as_view()(request)
		if not request.user.is_authenticated:
			return RegisterSignIn.as_view()(request)
		return RegisterUpdateView.as_view()(request)


class UnregisterView(LoginRequiredMixin, RedirectView):
	pattern_name = "accounts:profile"

	def get_redirect_url(self, *args, **kwargs):
		participant = self.request.user.profile
		participant.is_registered = False
		participant.save()
		messages.success(self.request, "Vous avez été désinscrit")
		return reverse(self.pattern_name)


# ==============================
# Admin views
# ==============================


class AdminView(SuperuserRequiredMixin, TemplateView):
	template_name = "admin.html"

	def get_metrics(self):
		registered = InterludesParticipant.objects.filter(is_registered = True)
		acts = InterludesActivity.objects.all()
		wishes = ActivityList.objects.filter(participant__is_registered=True)
		class metrics:
			participants = registered.count()
			ulm = registered.filter(school="U").count()
			lyon = registered.filter(school="L").count()
			rennes = registered.filter(school="R").count()
			saclay = registered.filter(school="P").count()
			non_registered = EmailUser.objects.filter(is_active=True).count() - participants

			meal1 = registered.filter(meal_friday_evening=True).count()
			meal2 = registered.filter(meal_saturday_morning=True).count()
			meal3 = registered.filter(meal_saturday_midday=True).count()
			meal4 = registered.filter(meal_saturday_evening=True).count()
			meal5 = registered.filter(meal_sunday_morning=True).count()
			meal6 = registered.filter(meal_sunday_midday=True).count()
			meals = meal1 + meal2 + meal3 + meal4 + meal5 + meal6

			# mugs = registered.filter(mug=True).count()
			sleeps = registered.filter(sleeps=True).count()

			activites = acts.count()
			act_ins = acts.filter(must_subscribe=True).count()
			wish = wishes.count()
			granted = wishes.filter(accepted=True).count()

		# validation de la repartition des activités
		accepted = wishes.filter(accepted=True)
		# order_by is useless but required
		counts = accepted.values("activity").annotate(total=Count("id")).order_by("activity")

		return metrics

	def validate_activity_participant_nb(self):
		""" Vérifie que le nombre de participant inscrit
		à chaque activité est compris entre le min et le max"""
		activities = InterludesActivity.objects.filter(must_subscribe=True, display=True)
		min_fails = ""
		max_fails = ""
		for act in activities:
			total = ActivityList.objects.filter(
				activity=act, accepted=True, participant__is_registered=True
			).aggregate(total=Count("id"))["total"]
			max = act.max_participants
			min = act.min_participants
			if max != 0 and max < total:
				max_fails += "<br> &bullet;&ensp;{}: {} inscrits (maximum {})".format(
					act.title, total, max
				)
			if min > total:
				min_fails += "<br> &bullet;&ensp;{}: {} inscrits (minimum {})".format(
					act.title, total, max
				)
		message = ""
		if min_fails:
			message += '<li class="error">Activités en sous-effectif : {}</li>'.format(min_fails)
		else:
			message += '<li class="success">Aucune activité en sous-effectif</li>'
		if max_fails:
			message += '<li class="error">Activités en sur-effectif : {}</li>'.format(max_fails)
		else:
			message += '<li class="success">Aucune activité en sur-effectif</li>'
		return message

	def validate_activity_conflicts(self):
		"""Vérifie que personne n'est inscrit à des activités simultanées"""
		activities = InterludesActivity.objects.filter(must_subscribe=True, display=True)
		conflicts = []
		for i, act1 in enumerate(activities):
			for act2 in activities[i+1:]:
				if act1.conflicts(act2):
					conflicts.append((act1, act2))
		base_qs = ActivityList.objects.filter(accepted=True, participant__is_registered=True)
		errors = ""
		for act1, act2 in conflicts:
			participants1 = base_qs.filter(activity=act1).values("participant")
			participants2 = base_qs.filter(activity=act1).values("participant")
			intersection = participants1 & participants2
			if intersection:
				print(intersection)
				errors += '<br> &bullet;&ensp; {} participe(nt) à la fois à "{}" et à "{}"'.format(
					",".join(str(InterludesParticipant.objects.get(id=x["participant"])) for x in intersection),
					act1.title, act2.title
				)

		if errors:
			return '<li class="error">Des participants ont plusieurs activités au même moment :{}</li>'.format(
				errors
			)
		return '<li class="success">Aucun inscrit à plusieurs activités simultanées</li>'

	def validate_activity_allocation(self):
		settings = SiteSettings.load()
		validations = '<ul class="messagelist">'

		# validate global settings
		if not settings.inscriptions_open:
			validations += '<li class="success">Les inscriptions sont fermées</li>'
		else:
			validations += '<li class="error">Les inscriptions sont encores ouvertes</li>'
		if settings.activities_allocated:
			validations += '<li class="success">La répartition est marquée comme effectuée</li>'
		else:
			validations += '<li class="error">La répartition n\'est pas marquée comme effectuée</li>'

		# longer validations
		validations += self.validate_activity_participant_nb()
		validations += self.validate_activity_conflicts()
		validations += '</ul>'

		user_email_nb = ActivityList.objects.filter(
			participant__is_registered=True
		).values("participant").distinct().count()
		orga_email_nb = InterludesActivity.objects.filter(
			display=True, must_subscribe=True, communicate_participants=True
		).count()

		return {
			"validations": validations,
			"user_email_nb": user_email_nb,
			"orga_email_nb": orga_email_nb,
			"validation_errors": '<li class="error">' in validations
		}

	def get_context_data(self, *args, **kwargs):
		context = super().get_context_data(*args, **kwargs)
		context["metrics"] = self.get_metrics()
		context.update(self.validate_activity_allocation())
		return context


class ExportActivities(SuperuserRequiredMixin, CSVWriteView):
	filename = "activites_interludes"
	model = InterludesActivity

class ExportParticipants(SuperuserRequiredMixin, CSVWriteView):
	filename = "participants_interludes"
	headers = [
		"id", "mail", "prénom", "nom", "ENS", "Dors sur place", "Tasse",
		"Repas vendredi", "Repas S matin", "Repas S midi", "Repas S soir",
		"Repas D matin", "Repas D soir"
	]
	def get_rows(self):
		profiles = InterludesParticipant.objects.filter(is_registered=True).all()
		rows = []
		for profile in profiles:
			rows.append([
				profile.user.id,
				profile.user.email,
				profile.user.first_name,
				profile.user.last_name,
				profile.school,
				profile.sleeps,
				profile.mug,
				profile.meal_friday_evening,
				profile.meal_saturday_morning,
				profile.meal_saturday_midday,
				profile.meal_saturday_evening,
				profile.meal_sunday_morning,
				profile.meal_sunday_midday,
			])
		return rows

class ExportActivityChoices(SuperuserRequiredMixin, CSVWriteView):
	filename = "choix_activite_interludes"
	model = ActivityList
	headers = ["id_participant", "nom_participant", "priorité", "nom_activité", "id_activité"]

	def get_rows(self):
		activities = ActivityList.objects.all()
		rows = []
		for act in activities:
			if act.participant.is_registered:
				rows.append([
					act.participant.id, str(act.participant), act.priority,
					str(act.activity), act.activity.id
				])
		return rows

class SendUserEmail(SuperuserRequiredMixin, RedirectView):
	"""Envoie aux utilisateurs leur repartition d'activité"""
	pattern_name = "site_admin"
	from_address = settings.DEFAULT_FROM_EMAIL

	def get_emails(self):
		"""genere les mails a envoyer"""
		# on envoie qu'au participant qui se sont inscrit à des activites
		participants = ActivityList.objects.filter(
			participant__is_registered=True
		).values("participant").distinct()
		emails = []
		for p in participants:
			participant = InterludesParticipant.objects.get(id = p["participant"])
			messages = render_to
			emails.append((
				"Vos activités interludes", # subject
				message,
				self.from_address, # From:
				[participant.user.email] # To:
			))
		return emails

	def send_emails(self):
		settings = SiteSettings.load()
		if settings.user_notified:
			messages.error(self.request, "Les participants ont déjà reçu un mail annonçant la répartition. Modifiez les réglages pour en envoyer un autre")
			return
		settings.user_notified = True
		settings.save()
		messages.success(self.request, "Email aux utilisateurs envoyé")
		send

	def get_redirect_url(self, *args, **kwargs):
		self.send_emails()
		return reverse(self.pattern_name)


# ==============================
# Sitemap
# ==============================


class StaticViewSitemap(Sitemap):
	"""Vue générant la sitemap.xml du site"""
	changefreq = 'monthly'

	def items(self):
		"""list of pages to appear in sitemap"""
		return ["home", "inscription", "activites", "FAQ"]

	def location(self, item):
		"""real url of an item"""
		return reverse(item)

	def priority(self, obj):
		"""priority to appear in sitemap"""
		# Priorize home page over the rest in search results
		if obj == "home" or obj == "":
				return 0.8
		else:
			return None # defaults to 0.5 when unset