#    Copyright (C) 2017  Alban Gruin
#
#    celcatsanitizer is free software; you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation; either version 2 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 General Public License for more details.
#
#    You should have received a copy of the GNU General Public License along
#    with celcatsanitizer; if not, write to the Free Software Foundation, Inc.,
#    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

from django.http import HttpResponse, Http404
from django.db.models import Count
from django.shortcuts import get_object_or_404, redirect, render
from django.utils import timezone
from django.core.mail import send_mail
from django.conf import settings
from django.template import Context, loader

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

import datetime

def index(request):
    timetables = Timetable.objects.all()
    groups = Group.objects.filter(tp__isnull=False).order_by("name")

    year, week = get_current_week()
    start, _ = get_week(year, week)
    groups_weeks = Course.objects.get_weeks(begin__gte=start).values("groups__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, "index.html", {"timetables": timetables, "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)
    courses = Course.objects.get_courses_for_group(group, begin__gte=start, begin__lt=end)
    last_update = LastUpdate.objects.get(timetable=timetable, week=week, year=year)

    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")