#    Copyright (C) 2017  Alban Gruin
#
#    celcatsanitizer is free software: you can redistribute it and/or modify
#    it under the terms of the GNU Affero General Public License as published
#    by the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    celcatsanitizer is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU Affero General Public License for more details.
#
#    You should have received a copy of the GNU Affero General Public License
#    along with celcatsanitizer.  If not, see <http://www.gnu.org/licenses/>.

from django.shortcuts import get_object_or_404, redirect, render
from django.core.mail import send_mail
from django.conf import settings
from django.template import Context, loader
from django.db.models import Count

from .forms import SubscribeForm
from .models import Timetable, LastUpdate, Group, Subscription, Course, Year
from .utils import get_current_week, get_week, group_courses

def index(request):
    years = Year.objects.order_by("name")
    return render(request, "index.html", {"years": years})

def mention_list(request, year_slug):
    year = get_object_or_404(Year, slug=year_slug)
    timetables = Timetable.objects.order_by("name").filter(year=year)

    return render(request, "mention_list.html", {"year": year, "timetables": timetables})

def group_list(request, year_slug, timetable_slug):
    get_object_or_404(Year, slug=year_slug)
    timetable = get_object_or_404(Timetable, slug=timetable_slug)
    groups = Group.objects.get_relevant_groups().order_by("name")

    year, week = get_current_week()
    start, _ = get_week(year, week)
    groups_weeks = Course.objects.get_weeks(begin__gte=start).values("group__timetable", "groups__mention", "groups__subgroup", "groups__td", "groups__tp", "year", "week")

    for group in groups:
        for group_week in groups_weeks:
            if group.corresponds_to(group_week["groups__timetable"], group_week["groups__mention"], group_week["groups__subgroup"], group_week["groups__td"], group_week["groups__tp"]):
                if not hasattr(group, "weeks"):
                    group.weeks = []

                date, _ = get_week(group_week["year"], group_week["week"])
                if date not in group.weeks:
                    group.weeks.append(date)

        if hasattr(group, "weeks"):
            group.weeks.sort()

    return render(request, "group_list.html", {"timetable": timetable, "groups": groups})

def timetable(request, timetable_slug, group_slug, year=None, week=None):
    if year is None or week is None:
        year, week = get_current_week()

    start, end = get_week(int(year), int(week))

    timetable = get_object_or_404(Timetable, slug=timetable_slug)
    group = get_object_or_404(Group, slug=group_slug, timetable=timetable)
    last_update = get_object_or_404(LastUpdate, timetable=timetable, week=week, year=year)
    courses = Course.objects.get_courses_for_group(group, begin__gte=start, begin__lt=end)

    grouped_courses = group_courses(courses)

    return render(request, "timetable.html", {"group": group, "courses": grouped_courses, "last_update": last_update.date, "year": year, "week": int(week)})

def subscribe(request, timetable_slug, group_slug, year, week):
    timetable = get_object_or_404(Timetable, slug=timetable_slug)
    group = get_object_or_404(Group, slug=group_slug, timetable=timetable)

    if request.method == "POST":
        form = SubscribeForm(request.POST)
        if form.is_valid():
            if not Subscription.objects.filter(email=request.POST["email"], group=group).exists():
                subscription = Subscription(email=request.POST["email"], group=group)
                subscription.save()

                template = loader.get_template("mail/mail_confirm.txt")
                context = Context({"group": group, "admins": settings.ADMINS, "token": subscription.token, "domain": settings.DEFAULT_DOMAIN})
                send_mail("Confirmation de l’abonnemenent", template.render(context), settings.DEFAULT_FROM_EMAIL, [request.POST["email"]])

            return redirect("timetable", timetable_slug=timetable_slug, group_slug=group_slug, year=year, week=int(week))
    else:
        form = SubscribeForm()

    return render(request, "subscribe.html", {"year": year, "week": week, "group": group, "form": form})

def confirm_subscription(request, token):
    subscription = Subscription.objects.filter(token=token).first()
    year, week = get_current_week()

    if subscription is not None and not subscription.active:
        subscription.active = True
        subscription.save()

    return redirect("timetable", timetable_slug=subscription.group.timetable.slug, group_slug=subscription.group.slug, year=year, week=week)

def cancel_subscription(request, token):
    subscription = Subscription.objects.filter(token=token).first()

    if subscription is not None:
        group = subscription.group
        subscription.delete()

        template = loader.get_template("mail/mail_unsubscribed.txt")
        context = Context({"group": group})
        send_mail("Confirmation de la désinscription", template.render(context), settings.DEFAULT_FROM_EMAIL, [subscription.email])

    return redirect("index")