# Copyright (C) 2018-2020 by BDE ENS Paris-Saclay
# SPDX-License-Identifier: GPL-3.0-or-later

from django.core.management import BaseCommand
from django.db.models import Sum, F

from note.models import Note, Transaction
from note.templatetags.pretty_money import pretty_money


class Command(BaseCommand):
    def add_arguments(self, parser):
        parser.add_argument('--sum-all', '-s', action='store_true', help='Check if the global sum is equal to zero')

    def handle(self, *args, **options):
        if options["sum_all"]:
            s = Note.objects.aggregate(Sum("balance"))["balance__sum"]
            if s:
                self.stderr.write(self.style.NOTICE("LA SOMME DES NOTES NE VAUT PAS ZÉRO : " + pretty_money(s)))
                exit(-1)
            else:
                self.stdout.write(self.style.SUCCESS("La somme des notes vaut bien zéro."))
                exit(0)

        error = False
        for note in Note.objects.all():
            balance = note.balance
            incoming = Transaction.objects.filter(valid=True, destination=note)\
                .annotate(total=F("quantity") * F("amount")).aggregate(Sum("total"))["total__sum"] or 0
            outcoming = Transaction.objects.filter(valid=True, source=note)\
                .annotate(total=F("quantity") * F("amount")).aggregate(Sum("total"))["total__sum"] or 0
            expected_balance = incoming - outcoming
            if expected_balance != balance:
                self.stderr.write(self.style.NOTICE("LA SOMME DES TRANSACTIONS DE LA NOTE {} NE CORRESPOND PAS "
                                                    "AVEC LE MONTANT RÉEL".format(str(note))))
                self.stderr.write(self.style.NOTICE("Attendu : {}, calculé : {}"
                                                    .format(pretty_money(balance), pretty_money(expected_balance))))
                error = True
        exit(1 if error else 0)