"""
web_admin tasks file
"""
import datetime

# third party imports
from celery import shared_task
from templated_email import send_templated_mail

# django imports
from django.conf import settings
from django.db.models import F, Window
from django.db.models.functions.window import Rank

# local imports
from base.constants import PENDING, IN_PROGRESS, JUNIOR
from guardian.models import JuniorTask
from junior.models import JuniorPoints
from notifications.constants import PENDING_TASK_EXPIRING, IN_PROGRESS_TASK_EXPIRING, NOTIFICATION_DICT, TOP_JUNIOR
from notifications.models import Notification
from notifications.utils import send_notification, get_from_user_details, send_notification_multiple_user


@shared_task
def send_email(recipient_list, template, context: dict = None):
    """
    used to send otp on email
    :param context:
    :param recipient_list: e-mail list
    :param template: email template
    """
    if context is None:
        context = {}
    from_email = settings.EMAIL_FROM_ADDRESS
    send_templated_mail(
        template_name=template,
        from_email=from_email,
        recipient_list=recipient_list,
        context=context
    )
    return True


@shared_task()
def notify_task_expiry():
    """
    task to send notification for those task which expiring soon
    :return:
    """
    all_pending_tasks = JuniorTask.objects.filter(
        task_status__in=[PENDING, IN_PROGRESS],
        due_date__range=[datetime.datetime.now().date(),
                         (datetime.datetime.now().date() + datetime.timedelta(days=1))])
    if pending_tasks := all_pending_tasks.filter(task_status=PENDING):
        for task in pending_tasks:
            send_notification(PENDING_TASK_EXPIRING, None, None, task.junior.auth.id,
                              {'task_id': task.id})
    if in_progress_tasks := all_pending_tasks.filter(task_status=IN_PROGRESS):
        for task in in_progress_tasks:
            send_notification(IN_PROGRESS_TASK_EXPIRING, task.junior.auth.id, JUNIOR, task.guardian.user.id,
                              {'task_id': task.id})
    return True


@shared_task()
def notify_top_junior():
    """
    task to send notification for top leaderboard junior to all junior's
    :return:
    """
    junior_points_qs = JuniorPoints.objects.filter(
                                    junior__is_verified=True
                                    ).select_related(
                                    'junior', 'junior__auth'
                                    ).annotate(rank=Window(
                                            expression=Rank(),
                                            order_by=[F('total_points').desc(), 'junior__created_at'])
                                    ).order_by('-total_points', 'junior__created_at')

    prev_top_position = junior_points_qs.filter(position=1).first()
    new_top_position = junior_points_qs.filter(rank=1).first()
    if prev_top_position != new_top_position:
        send_notification_multiple_user(TOP_JUNIOR, new_top_position.junior.auth.id, JUNIOR,
                                        {'points': new_top_position.total_points})
    for junior_point in junior_points_qs:
        junior_point.position = junior_point.rank
        junior_point.save()
    return True