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

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

    # TODO: check for existing bills
    def handle(self, *args, **options):
        customers = User.objects.all()
        print("Processing {} users.".format(customers.count()))
        for customer in customers:
            orders = Order.objects.filter(owner=customer)

            # Pay all non-billed usage untill now.
            bill_starting_date = timezone.now()
            bill_ending_date = timezone.now()

            billed_orders = []
            for order in orders:
                print(order)
                if True: # FIXME
                    billed_orders.append(order)

                    # Update starting date if need be.
                    if order.starting_date < bill_starting_date:
                        bill_starting_date = order.starting_date

            if len(billed_orders) > 0:
              bill = Bill(owner=customer,
                       starting_date=bill_starting_date,
                       ending_date=bill_starting_date,
                       due_date=timezone.now() + timedelta(days=10))
              bill.save()

              for order in billed_orders:
                  print(order)
                  order.bill.add(bill)

              print("Created bill {} for user {}".format(bill.uuid, customer.username))

        print("=> Done.")