from __future__ import unicode_literals

import django_filters
from netaddr import EUI
from netaddr.core import AddrFormatError

from django.db.models import Q

from dcim.models import DeviceRole, Interface, Platform, Site
from extras.filters import CustomFieldFilterSet
from tenancy.models import Tenant
from utilities.filters import NumericInFilter
from .constants import STATUS_CHOICES
from .models import Cluster, ClusterGroup, ClusterType, VirtualMachine


class ClusterFilter(CustomFieldFilterSet):
    id__in = NumericInFilter(name='id', lookup_expr='in')
    q = django_filters.CharFilter(
        method='search',
        label='Search',
    )
    group_id = django_filters.ModelMultipleChoiceFilter(
        queryset=ClusterGroup.objects.all(),
        label='Parent group (ID)',
    )
    group = django_filters.ModelMultipleChoiceFilter(
        name='group__slug',
        queryset=ClusterGroup.objects.all(),
        to_field_name='slug',
        label='Parent group (slug)',
    )
    type_id = django_filters.ModelMultipleChoiceFilter(
        queryset=ClusterType.objects.all(),
        label='Cluster type (ID)',
    )
    type = django_filters.ModelMultipleChoiceFilter(
        name='type__slug',
        queryset=ClusterType.objects.all(),
        to_field_name='slug',
        label='Cluster type (slug)',
    )
    site_id = django_filters.ModelMultipleChoiceFilter(
        queryset=Site.objects.all(),
        label='Site (ID)',
    )
    site = django_filters.ModelMultipleChoiceFilter(
        name='site__slug',
        queryset=Site.objects.all(),
        to_field_name='slug',
        label='Site (slug)',
    )

    class Meta:
        model = Cluster
        fields = ['name']

    def search(self, queryset, name, value):
        if not value.strip():
            return queryset
        return queryset.filter(
            Q(name__icontains=value) |
            Q(comments__icontains=value)
        )


class VirtualMachineFilter(CustomFieldFilterSet):
    id__in = NumericInFilter(name='id', lookup_expr='in')
    q = django_filters.CharFilter(
        method='search',
        label='Search',
    )
    status = django_filters.MultipleChoiceFilter(
        choices=STATUS_CHOICES
    )
    cluster_group_id = django_filters.ModelMultipleChoiceFilter(
        name='cluster__group',
        queryset=ClusterGroup.objects.all(),
        label='Cluster group (ID)',
    )
    cluster_group = django_filters.ModelMultipleChoiceFilter(
        name='cluster__group__slug',
        queryset=ClusterGroup.objects.all(),
        to_field_name='slug',
        label='Cluster group (slug)',
    )
    cluster_id = django_filters.ModelMultipleChoiceFilter(
        queryset=Cluster.objects.all(),
        label='Cluster (ID)',
    )
    role_id = django_filters.ModelMultipleChoiceFilter(
        queryset=DeviceRole.objects.all(),
        label='Role (ID)',
    )
    role = django_filters.ModelMultipleChoiceFilter(
        name='role__slug',
        queryset=DeviceRole.objects.all(),
        to_field_name='slug',
        label='Role (slug)',
    )
    tenant_id = django_filters.ModelMultipleChoiceFilter(
        queryset=Tenant.objects.all(),
        label='Tenant (ID)',
    )
    tenant = django_filters.ModelMultipleChoiceFilter(
        name='tenant__slug',
        queryset=Tenant.objects.all(),
        to_field_name='slug',
        label='Tenant (slug)',
    )
    platform_id = django_filters.ModelMultipleChoiceFilter(
        queryset=Platform.objects.all(),
        label='Platform (ID)',
    )
    platform = django_filters.ModelMultipleChoiceFilter(
        name='platform__slug',
        queryset=Platform.objects.all(),
        to_field_name='slug',
        label='Platform (slug)',
    )

    class Meta:
        model = VirtualMachine
        fields = ['name', 'cluster']

    def search(self, queryset, name, value):
        if not value.strip():
            return queryset
        return queryset.filter(
            Q(name__icontains=value) |
            Q(comments__icontains=value)
        )


class InterfaceFilter(django_filters.FilterSet):
    virtual_machine_id = django_filters.ModelMultipleChoiceFilter(
        name='virtual_machine',
        queryset=VirtualMachine.objects.all(),
        label='Virtual machine (ID)',
    )
    virtual_machine = django_filters.ModelMultipleChoiceFilter(
        name='virtual_machine__name',
        queryset=VirtualMachine.objects.all(),
        to_field_name='name',
        label='Virtual machine',
    )
    mac_address = django_filters.CharFilter(
        method='_mac_address',
        label='MAC address',
    )

    class Meta:
        model = Interface
        fields = ['name', 'enabled', 'mtu']

    def _mac_address(self, queryset, name, value):
        value = value.strip()
        if not value:
            return queryset
        try:
            mac = EUI(value.strip())
            return queryset.filter(mac_address=mac)
        except AddrFormatError:
            return queryset.none()