import zoneinfo
from datetime import datetime, timedelta
from typing import Union
from urllib.parse import urljoin
from django.conf import settings
from django.urls import reverse
from django.utils import timezone
from django.utils.formats import date_format
from django.utils.translation import gettext_lazy as _
from django.utils.translation import ngettext
from aleksis.core.models import Notification, Person
from aleksis.core.util.core_helpers import get_site_preferences
from ..models import Event, ExtraLesson, LessonSubstitution, SupervisionSubstitution
def send_notifications_for_object(
instance: Union[ExtraLesson, LessonSubstitution, Event, SupervisionSubstitution]
):
"""Send notifications for a change object."""
recipients = []
if isinstance(instance, LessonSubstitution):
recipients += instance.lesson_period.lesson.teachers.all()
recipients += instance.teachers.all()
recipients += Person.objects.filter(
member_of__in=instance.lesson_period.lesson.groups.all()
)
elif isinstance(instance, Event):
recipients += instance.teachers.all()
recipients += Person.objects.filter(member_of__in=instance.groups.all())
elif isinstance(instance, ExtraLesson):
recipients += instance.teachers.all()
recipients += Person.objects.filter(member_of__in=instance.groups.all())
elif isinstance(instance, SupervisionSubstitution):
recipients.append(instance.teacher)
recipients.append(instance.supervision.teacher)
description = ""
if isinstance(instance, LessonSubstitution):
# Date, lesson, subject
subject = instance.lesson_period.lesson.subject
day = instance.date
period = instance.lesson_period.period
if instance.cancelled:
description += (
_(
"The {subject} lesson in the {period}. period on {day} has been cancelled."
).format(subject=subject.name, period=period.period, day=date_format(day))
+ " "
)
else:
description += (
_(
"The {subject} lesson in the {period}. period "
"on {day} has some current changes."
).format(subject=subject.name, period=period.period, day=date_format(day))
+ " "
)
if instance.teachers.all():
description += (
ngettext(
"The teacher {old} is substituted by {new}.",
"The teachers {old} are substituted by {new}.",
instance.teachers.count(),
).format(
old=instance.lesson_period.lesson.teacher_names,
new=instance.teacher_names,
)
+ " "
)
if instance.subject:
description += (
_("The subject is changed to {subject}.").format(subject=instance.subject.name)
+ " "
)
if instance.room:
description += (
_("The lesson is moved from {old} to {new}.").format(
old=instance.lesson_period.room.name,
new=instance.room.name,
)
+ " "
)
if instance.comment:
description += (
_("There is an additional comment: {comment}.").format(comment=instance.comment)
+ " "
)
elif isinstance(instance, Event):
if instance.date_start != instance.date_end:
description += (
_(
"There is an event that starts on {date_start}, {period_from}. period "
"and ends on {date_end}, {period_to}. period:"
).format(
date_start=date_format(instance.date_start),
date_end=date_format(instance.date_end),
period_from=instance.period_from.period,
period_to=instance.period_to.period,
)
+ "\n"
)
else:
description += (
_(
"There is an event on {date} from the "
"{period_from}. period to the {period_to}. period:"
).format(
date=date_format(instance.date_start),
period_from=instance.period_from.period,
period_to=instance.period_to.period,
)
+ "\n"
)
if instance.groups.all():
description += _("Groups: {groups}").format(groups=instance.group_names) + "\n"
if instance.teachers.all():
description += _("Teachers: {teachers}").format(teachers=instance.teacher_names) + "\n"
if instance.rooms.all():
description += (
_("Rooms: {rooms}").format(
rooms=", ".join([room.name for room in instance.rooms.all()])
)
+ "\n"
)
elif isinstance(instance, ExtraLesson):
description += (
_("There is an extra lesson on {date} in the {period}. period:").format(
date=date_format(instance.date),
period=instance.period.period,
)
+ "\n"
)
if instance.groups.all():
description += _("Groups: {groups}").format(groups=instance.group_names) + "\n"
if instance.room:
description += _("Subject: {subject}").format(subject=instance.subject.name) + "\n"
if instance.teachers.all():
description += _("Teachers: {teachers}").format(teachers=instance.teacher_names) + "\n"
if instance.room:
description += _("Room: {room}").format(room=instance.room.name) + "\n"
if instance.comment:
description += _("Comment: {comment}.").format(comment=instance.comment) + "\n"
elif isinstance(instance, SupervisionSubstitution):
description += _(
"The supervision of {old} on {date} between the {period_from}. period "
"and the {period_to}. period in the area {area} is substituted by {new}."
).format(
old=instance.supervision.teacher.full_name,
date=date_format(instance.date),
period_from=instance.supervision.break_item.after_period_number,
period_to=instance.supervision.break_item.before_period_number,
area=instance.supervision.area.name,
new=instance.teacher.full_name,
)
day = instance.date if hasattr(instance, "date") else instance.date_start
url = urljoin(
settings.BASE_URL,
reverse(
"my_timetable_by_date",
args=[day.year, day.month, day.day],
),
)
dt_start, dt_end = instance.time_range
dt_start = dt_start.replace(tzinfo=zoneinfo.ZoneInfo(settings.TIME_ZONE))
dt_end = dt_end.replace(tzinfo=zoneinfo.ZoneInfo(settings.TIME_ZONE))
send_time = get_site_preferences()["chronos__time_for_sending_notifications"]
number_of_days = get_site_preferences()["chronos__days_in_advance_notifications"]
start_range = timezone.now().replace(hour=send_time.hour, minute=send_time.minute)
if timezone.now().time() > send_time:
start_range = start_range - timedelta(days=1)
end_range = start_range + timedelta(days=number_of_days)
if dt_start < start_range and dt_end < end_range:
# Skip this, because the change is in the past
return
if dt_start <= end_range and dt_end >= start_range:
# Send immediately
send_at = timezone.now()
else:
# Schedule for later
send_at = datetime.combine(
dt_start.date() - timedelta(days=number_of_days), send_time
).replace(tzinfo=zoneinfo.ZoneInfo(settings.TIME_ZONE))
for recipient in recipients:
if recipient.preferences["chronos__send_notifications"]:
n = Notification(
recipient=recipient,
sender=_("Timetable"),
title=_("There are current changes to your timetable."),
description=description,
link=url,
send_at=send_at,
)
n.save()