# Copyright (C) 2018-2021 by BDE ENS Paris-Saclay
# SPDX-License-Identifier: GPL-3.0-or-later

from datetime import timedelta

from django.core.management import BaseCommand
from django.db.models import Q
from django.template.loader import render_to_string
from django.utils import timezone
from django.utils.translation import activate

from note.models import NoteUser, Transaction
from note.tables import HistoryTable


class Command(BaseCommand):
    def add_arguments(self, parser):
        parser.add_argument('--notes', '-n', type=int, nargs='+', help='Select note ids')
        parser.add_argument('--debug', '-d', action='store_true', help='Debug mode, print mails in stdout')

    def handle(self, *args, **options):
        activate('fr')
        if 'notes' in options and options['notes']:
            notes = NoteUser.objects.filter(pk__in=options['notes']).all()
        else:
            notes = NoteUser.objects.filter(
                user__memberships__date_end__gte=timezone.now(),
                user__profile__report_frequency__gt=0,
            ).distinct().all()
        for note in notes:
            now = timezone.now()
            last_report = note.user.profile.last_report
            delta = now.date() - last_report.date()
            if delta.days < note.user.profile.report_frequency:
                continue
            if not options["debug"]:
                note.user.profile.last_report = now
                note.user.profile.save()
            last_transactions = Transaction.objects.filter(
                Q(source=note) | Q(destination=note),
                created_at__gte=last_report,
            ).order_by("created_at").all()
            if not last_transactions.exists():
                continue

            table = HistoryTable(last_transactions)
            incoming = sum(tr.total for tr in last_transactions if tr.destination.pk == note.pk if tr.valid)
            outcoming = sum(tr.total for tr in last_transactions if tr.source.pk == note.pk if tr.valid)
            context = dict(
                user=note.user,
                table=table,
                last_transactions=last_transactions,
                incoming=incoming,
                outcoming=outcoming,
                diff=incoming - outcoming,
                now=now,
                last_report=last_report,
            )
            plain = render_to_string("note/mails/weekly_report.txt", context)
            html = render_to_string("note/mails/weekly_report.html", context)
            if options["debug"]:
                self.stdout.write(plain)
            else:
                note.user.email_user("[Note Kfet] Rapport de la Note Kfet", plain, html_message=html)