from django.db.models import Q, F
from django.utils import timezone

from services.models import IPResource, IPResourceState, ServiceAllocation

import re
from ipaddress import IPv4Address, AddressValueError
import logging
from itertools import groupby


logger = logging.getLogger(__name__)


def fastpinger_update(f):
    now = timezone.now()

    regex = re.compile('^(?P<ip>[0-9.]+)[ ]+: (?P<p1>([0-9]+.[0-9]+|-)) (?P<p2>([0-9]+.[0-9]+|-))'
                       ' (?P<p3>([0-9]+.[0-9]+|-)) (?P<p4>([0-9]+.[0-9]+|-)) (?P<p5>([0-9]+.[0-9]+|-))$')

    up, down, unknown = set(), set(), set()
    for line in f:
        try:
            line = line.decode('utf-8')
        except UnicodeDecodeError:
            continue
        g = regex.match(line)
        if not g:
            continue
        try:
            ip = IPv4Address(g.group('ip'))
        except AddressValueError:
            continue
        p = [ g.group('p%d' % i) for i in [1, 2, 3, 4, 5] ]
        if all(map(lambda p: p == '-', p)):
            down.add(ip.compressed)
        else:
            up.add(ip.compressed)

    up = up - down # suppression des doublons

    leaves = {
        IPResourceState.STATE_DOWN: 0,
        IPResourceState.STATE_UP: 0,
        IPResourceState.STATE_UNKNOWN: 0,
    }

    become_down = IPResource.objects.exclude(last_state__state=IPResourceState.STATE_DOWN).filter(ip__in=down)
    for ip in become_down:
        leaves[ip.last_state.state] += 1
        if ip.last_state.state == IPResourceState.STATE_UP:
            ip.last_time_up = now
        ip.last_state = IPResourceState.objects.create(ip=ip, date=now, state=IPResourceState.STATE_DOWN)
        ip.save()
    become_up = IPResource.objects.exclude(last_state__state=IPResourceState.STATE_UP).filter(ip__in=up)
    for ip in become_up:
        leaves[ip.last_state.state] += 1
        ip.last_state = IPResourceState.objects.create(ip=ip, date=now, state=IPResourceState.STATE_UP)
        ip.save()
    become_unknown = IPResource.objects.exclude(last_state__state=IPResourceState.STATE_UNKNOWN).exclude(Q(pk__in=up) | Q(pk__in=down))
    for ip in become_unknown:
        leaves[ip.last_state.state] += 1
        if ip.last_state.state == IPResourceState.STATE_UP:
            ip.last_time_up = now
        ip.last_state = IPResourceState.objects.create(ip=ip, date=now, state=IPResourceState.STATE_UNKNOWN)
        ip.save()


    down_count = IPResource.objects.filter(last_state__state=IPResourceState.STATE_DOWN).count()
    up_count = IPResource.objects.filter(last_state__state=IPResourceState.STATE_UP).count()
    unknown_count = IPResource.objects.filter(last_state__state=IPResourceState.STATE_UNKNOWN).count()

    stats = "UP: %d (-%d+%d), DOWN: %d (-%d+%d), UNKNOWN: %d (-%d+%d)" \
            % (up_count, leaves[IPResourceState.STATE_UP], len(become_up), \
               down_count, leaves[IPResourceState.STATE_DOWN], len(become_down), \
               unknown_count, leaves[IPResourceState.STATE_UNKNOWN], len(become_unknown))
    return stats