from django.core.management.base import BaseCommand, CommandError

import time
from api.models import Order
from api.logics import Logics
from django.utils import timezone

class Command(BaseCommand):
    help = 'Follows all active hold invoices'

    # def add_arguments(self, parser):
    #     parser.add_argument('debug', nargs='+', type=boolean)

    def clean_orders(self, *args, **options):
        ''' Continuously checks order expiration times for 1 hour. If order
        has expires, it calls the logics module for expiration handling.'''

        # TODO handle 'database is locked'
        
        do_nothing = [Order.Status.DEL, Order.Status.UCA,
                    Order.Status.EXP, Order.Status.FSE,
                    Order.Status.DIS, Order.Status.CCA,
                    Order.Status.PAY, Order.Status.SUC,
                    Order.Status.FAI, Order.Status.MLD,
                    Order.Status.TLD, Order.Status.WFR]

        while True:
            time.sleep(5)

            queryset = Order.objects.exclude(status__in=do_nothing)
            queryset = queryset.filter(expires_at__lt=timezone.now()) # expires at lower than now

            debug = {}
            debug['num_expired_orders'] = len(queryset)
            debug['expired_orders'] = []

            for idx, order in enumerate(queryset):
                context = str(order)+ " was "+ Order.Status(order.status).label
                try:
                    if Logics.order_expires(order): # Order send to expire here
                        debug['expired_orders'].append({idx:context})
                
                # It should not happen, but if it cannot locate the hold invoice 
                # it probably was cancelled by another thread, make it expire anyway.
                except Exception as e:
                    if 'unable to locate invoice' in str(e): 
                        self.stdout.write(str(e))
                        order.status = Order.Status.EXP
                        order.save()
                        debug['expired_orders'].append({idx:context})
                    

            if debug['num_expired_orders'] > 0:    
                self.stdout.write(str(timezone.now()))
                self.stdout.write(str(debug))
    
    def handle(self, *args, **options):
        ''' Never mind database locked error, keep going, print them out'''
        try:
            self.clean_orders()
        except Exception as e:
            if 'database is locked' in str(e):
                self.stdout.write('database is locked')
            
            self.stdout.write(e)