# coding=utf-8
import logging
from django.core.management.base import BaseCommand
from django.db.models import Count, Max, Min
from django.utils.timezone import now
from cla_butler.stack import is_first_instance, InstanceNotInAsgException, StackException
from cla_eventlog.models import Log

logger = logging.getLogger(__name__)


class Command(BaseCommand):
    help = 'LGA-294 specific monitoring command. Alert when multiple outcome codes ' \
           'that should only occur once are found for today (since 00:00)'

    def handle(self, *args, **options):
        if self.should_run_housekeeping(**options):
            self.check_for_multiple_outcome_codes()
        else:
            logger.debug('LGA-294 Skip check_for_multiple_outcome_codes: running on secondary instance')

    @staticmethod
    def check_for_multiple_outcome_codes():
        # Outcome codes defined to appear only once on a case:
        # https://docs.google.com/spreadsheets/d/1hN64bA_H2a_0eC_5-k-0IY2-RKbCor2VGflp1ykQGa0/
        start_of_today = now().replace(hour=0, minute=0, second=0, microsecond=0)
        once_only_codes = ['PCB', 'COPE', 'DUPL', 'MRNB', 'NCOE', 'DESP', 'DECL', 'MRCC', 'NRES', 'CPTA',
                           'COSPF', 'SPFM', 'SPFN', 'DREFER', 'COI', 'CLSP', 'MANALC', 'MANREF', 'MIS',
                           'MIS-MEANS', 'MIS-OOS', 'REF-EXT', 'REF-INT', 'REFSP', 'REOPEN', 'SPOR', 'WROF']

        once_only_events_today = Log.objects.filter(created__gte=start_of_today, code__in=once_only_codes)
        once_only_codes_today = once_only_events_today.only('case__reference', 'code', 'created')
        once_only_codes_today_counts = once_only_codes_today.values('case__reference', 'code') \
            .annotate(total=Count('code'), earliest=Min('created'), latest=Max('created'))
        multiple_codes_today = once_only_codes_today_counts.filter(total__gt=1).order_by('-total')

        if multiple_codes_today.exists():
            for i in multiple_codes_today:
                logger.warning('LGA-294 investigation. Multiple outcome codes today for case: {}'.format(i))
        else:
            logger.info('LGA-294 No multiple outcome codes found for today')

    @staticmethod
    def should_run_housekeeping(**options):
        if options.get('force', False):
            return True
        try:
            return is_first_instance()
        except InstanceNotInAsgException:
            logger.info('EC2 instance not in an ASG')
            return True
        except StackException:
            logger.info('Not running on EC2 instance')
            return True

Check for multiple outcome codes occurring today