from django.core.management.base import BaseCommand
from uncloud_auth.models import User
from uncloud_pay.models import Order, Bill, PaymentMethod, get_balance_for

from datetime import timedelta
from django.utils import timezone

class Command(BaseCommand):
    help = 'Generate bills and charge customers if necessary.'

    def add_arguments(self, parser):
        pass

    def handle(self, *args, **options):
        users = User.objects.all()
        print("Processing {} users.".format(users.count()))
        for user in users:
            balance = get_balance_for(user)
            if balance < 0:
                print("User {} has negative balance ({}), charging.".format(user.username, balance))
                payment_method = PaymentMethod.get_primary_for(user)
                if payment_method != None:
                    amount_to_be_charged = abs(balance)
                    charge_ok = payment_method.charge(amount_to_be_charged)
                    if not charge_ok:
                        print("ERR: charging {} with method {} failed"
                                .format(user.username, payment_method.uuid)
                                )
                else:
                    print("ERR: no payment method registered for {}".format(user.username))
        print("=> Done.")