from django import forms
from django.db.models import Count

from dcim.models import Site, Rack, Device, Interface
from extras.forms import CustomFieldForm, CustomFieldBulkEditForm, CustomFieldFilterForm
from tenancy.forms import TenancyForm
from tenancy.models import Tenant
from utilities.forms import (
    APISelect, BootstrapMixin, BulkEditNullBooleanSelect, BulkImportForm, ChainedModelChoiceField, CSVDataField,
    ExpandableIPAddressField, FilterChoiceField, Livesearch, ReturnURLForm, SlugField, add_blank_choice,
)

from .models import (
    Aggregate, IPAddress, IPADDRESS_STATUS_CHOICES, Prefix, PREFIX_STATUS_CHOICES, RIR, Role, Service, VLAN,
    VLANGroup, VLAN_STATUS_CHOICES, VRF,
)


IP_FAMILY_CHOICES = [
    ('', 'All'),
    (4, 'IPv4'),
    (6, 'IPv6'),
]

PREFIX_MASK_LENGTH_CHOICES = [
    ('', '---------'),
] + [(i, i) for i in range(1, 128)]

IPADDRESS_MASK_LENGTH_CHOICES = PREFIX_MASK_LENGTH_CHOICES + [(128, 128)]


#
# VRFs
#

class VRFForm(BootstrapMixin, TenancyForm, CustomFieldForm):

    class Meta:
        model = VRF
        fields = ['name', 'rd', 'enforce_unique', 'description', 'tenant_group', 'tenant']
        labels = {
            'rd': "RD",
        }
        help_texts = {
            'rd': "Route distinguisher in any format",
        }


class VRFFromCSVForm(forms.ModelForm):
    tenant = forms.ModelChoiceField(Tenant.objects.all(), to_field_name='name', required=False,
                                    error_messages={'invalid_choice': 'Tenant not found.'})

    class Meta:
        model = VRF
        fields = ['name', 'rd', 'tenant', 'enforce_unique', 'description']


class VRFImportForm(BootstrapMixin, BulkImportForm):
    csv = CSVDataField(csv_form=VRFFromCSVForm)


class VRFBulkEditForm(BootstrapMixin, CustomFieldBulkEditForm):
    pk = forms.ModelMultipleChoiceField(queryset=VRF.objects.all(), widget=forms.MultipleHiddenInput)
    tenant = forms.ModelChoiceField(queryset=Tenant.objects.all(), required=False)
    enforce_unique = forms.NullBooleanField(
        required=False, widget=BulkEditNullBooleanSelect, label='Enforce unique space'
    )
    description = forms.CharField(max_length=100, required=False)

    class Meta:
        nullable_fields = ['tenant', 'description']


class VRFFilterForm(BootstrapMixin, CustomFieldFilterForm):
    model = VRF
    q = forms.CharField(required=False, label='Search')
    tenant = FilterChoiceField(queryset=Tenant.objects.annotate(filter_count=Count('vrfs')), to_field_name='slug',
                               null_option=(0, None))


#
# RIRs
#

class RIRForm(BootstrapMixin, forms.ModelForm):
    slug = SlugField()

    class Meta:
        model = RIR
        fields = ['name', 'slug', 'is_private']


class RIRFilterForm(BootstrapMixin, forms.Form):
    is_private = forms.NullBooleanField(required=False, label='Private', widget=forms.Select(choices=[
        ('', '---------'),
        ('True', 'Yes'),
        ('False', 'No'),
    ]))


#
# Aggregates
#

class AggregateForm(BootstrapMixin, CustomFieldForm):

    class Meta:
        model = Aggregate
        fields = ['prefix', 'rir', 'date_added', 'description']
        help_texts = {
            'prefix': "IPv4 or IPv6 network",
            'rir': "Regional Internet Registry responsible for this prefix",
            'date_added': "Format: YYYY-MM-DD",
        }


class AggregateFromCSVForm(forms.ModelForm):
    rir = forms.ModelChoiceField(queryset=RIR.objects.all(), to_field_name='name',
                                 error_messages={'invalid_choice': 'RIR not found.'})

    class Meta:
        model = Aggregate
        fields = ['prefix', 'rir', 'date_added', 'description']


class AggregateImportForm(BootstrapMixin, BulkImportForm):
    csv = CSVDataField(csv_form=AggregateFromCSVForm)


class AggregateBulkEditForm(BootstrapMixin, CustomFieldBulkEditForm):
    pk = forms.ModelMultipleChoiceField(queryset=Aggregate.objects.all(), widget=forms.MultipleHiddenInput)
    rir = forms.ModelChoiceField(queryset=RIR.objects.all(), required=False, label='RIR')
    date_added = forms.DateField(required=False)
    description = forms.CharField(max_length=100, required=False)

    class Meta:
        nullable_fields = ['date_added', 'description']


class AggregateFilterForm(BootstrapMixin, CustomFieldFilterForm):
    model = Aggregate
    q = forms.CharField(required=False, label='Search')
    family = forms.ChoiceField(required=False, choices=IP_FAMILY_CHOICES, label='Address Family')
    rir = FilterChoiceField(
        queryset=RIR.objects.annotate(filter_count=Count('aggregates')),
        to_field_name='slug',
        label='RIR'
    )


#
# Roles
#

class RoleForm(BootstrapMixin, forms.ModelForm):
    slug = SlugField()

    class Meta:
        model = Role
        fields = ['name', 'slug']


#
# Prefixes
#

class PrefixForm(BootstrapMixin, TenancyForm, CustomFieldForm):
    site = forms.ModelChoiceField(
        queryset=Site.objects.all(), required=False, label='Site', widget=forms.Select(
            attrs={'filter-for': 'vlan', 'nullable': 'true'}
        )
    )
    vlan = ChainedModelChoiceField(
        queryset=VLAN.objects.all(), chains={'site': 'site'}, required=False, label='VLAN', widget=APISelect(
            api_url='/api/ipam/vlans/?site_id={{site}}', display_field='display_name'
        )
    )

    class Meta:
        model = Prefix
        fields = ['prefix', 'vrf', 'site', 'vlan', 'status', 'role', 'is_pool', 'description', 'tenant_group', 'tenant']

    def __init__(self, *args, **kwargs):
        super(PrefixForm, self).__init__(*args, **kwargs)

        self.fields['vrf'].empty_label = 'Global'


class PrefixFromCSVForm(forms.ModelForm):
    vrf = forms.ModelChoiceField(queryset=VRF.objects.all(), required=False, to_field_name='rd',
                                 error_messages={'invalid_choice': 'VRF not found.'})
    tenant = forms.ModelChoiceField(Tenant.objects.all(), to_field_name='name', required=False,
                                    error_messages={'invalid_choice': 'Tenant not found.'})
    site = forms.ModelChoiceField(queryset=Site.objects.all(), required=False, to_field_name='name',
                                  error_messages={'invalid_choice': 'Site not found.'})
    vlan_group_name = forms.CharField(required=False)
    vlan_vid = forms.IntegerField(required=False)
    status_name = forms.ChoiceField(choices=[(s[1], s[0]) for s in PREFIX_STATUS_CHOICES])
    role = forms.ModelChoiceField(queryset=Role.objects.all(), required=False, to_field_name='name',
                                  error_messages={'invalid_choice': 'Invalid role.'})

    class Meta:
        model = Prefix
        fields = ['prefix', 'vrf', 'tenant', 'site', 'vlan_group_name', 'vlan_vid', 'status_name', 'role', 'is_pool',
                  'description']

    def clean(self):

        super(PrefixFromCSVForm, self).clean()

        site = self.cleaned_data.get('site')
        vlan_group_name = self.cleaned_data.get('vlan_group_name')
        vlan_vid = self.cleaned_data.get('vlan_vid')
        vlan_group = None

        # Validate VLAN group
        if vlan_group_name:
            try:
                vlan_group = VLANGroup.objects.get(site=site, name=vlan_group_name)
            except VLANGroup.DoesNotExist:
                if site:
                    self.add_error('vlan_group_name', "Invalid VLAN group ({} - {}).".format(site, vlan_group_name))
                else:
                    self.add_error('vlan_group_name', "Invalid global VLAN group ({}).".format(vlan_group_name))

        # Validate VLAN
        if vlan_vid:
            try:
                self.instance.vlan = VLAN.objects.get(site=site, group=vlan_group, vid=vlan_vid)
            except VLAN.DoesNotExist:
                if site:
                    self.add_error('vlan_vid', "Invalid VLAN ID ({}) for site {}.".format(vlan_vid, site))
                elif vlan_group:
                    self.add_error('vlan_vid', "Invalid VLAN ID ({}) for group {}.".format(vlan_vid, vlan_group_name))
                elif not vlan_group_name:
                    self.add_error('vlan_vid', "Invalid global VLAN ID ({}).".format(vlan_vid))
            except VLAN.MultipleObjectsReturned:
                self.add_error('vlan_vid', "Multiple VLANs found ({} - VID {})".format(site, vlan_vid))

    def save(self, *args, **kwargs):

        # Assign Prefix status by name
        self.instance.status = dict(self.fields['status_name'].choices)[self.cleaned_data['status_name']]

        return super(PrefixFromCSVForm, self).save(*args, **kwargs)


class PrefixImportForm(BootstrapMixin, BulkImportForm):
    csv = CSVDataField(csv_form=PrefixFromCSVForm)


class PrefixBulkEditForm(BootstrapMixin, CustomFieldBulkEditForm):
    pk = forms.ModelMultipleChoiceField(queryset=Prefix.objects.all(), widget=forms.MultipleHiddenInput)
    site = forms.ModelChoiceField(queryset=Site.objects.all(), required=False)
    vrf = forms.ModelChoiceField(queryset=VRF.objects.all(), required=False, label='VRF')
    tenant = forms.ModelChoiceField(queryset=Tenant.objects.all(), required=False)
    status = forms.ChoiceField(choices=add_blank_choice(PREFIX_STATUS_CHOICES), required=False)
    role = forms.ModelChoiceField(queryset=Role.objects.all(), required=False)
    is_pool = forms.NullBooleanField(required=False, widget=BulkEditNullBooleanSelect, label='Is a pool')
    description = forms.CharField(max_length=100, required=False)

    class Meta:
        nullable_fields = ['site', 'vrf', 'tenant', 'role', 'description']


def prefix_status_choices():
    status_counts = {}
    for status in Prefix.objects.values('status').annotate(count=Count('status')).order_by('status'):
        status_counts[status['status']] = status['count']
    return [(s[0], u'{} ({})'.format(s[1], status_counts.get(s[0], 0))) for s in PREFIX_STATUS_CHOICES]


class PrefixFilterForm(BootstrapMixin, CustomFieldFilterForm):
    model = Prefix
    q = forms.CharField(required=False, label='Search')
    parent = forms.CharField(required=False, label='Parent prefix', widget=forms.TextInput(attrs={
        'placeholder': 'Prefix',
    }))
    family = forms.ChoiceField(required=False, choices=IP_FAMILY_CHOICES, label='Address family')
    mask_length = forms.ChoiceField(required=False, choices=PREFIX_MASK_LENGTH_CHOICES, label='Mask length')
    vrf = FilterChoiceField(
        queryset=VRF.objects.annotate(filter_count=Count('prefixes')),
        to_field_name='rd',
        label='VRF',
        null_option=(0, 'Global')
    )
    tenant = FilterChoiceField(
        queryset=Tenant.objects.annotate(filter_count=Count('prefixes')),
        to_field_name='slug',
        null_option=(0, 'None')
    )
    status = forms.MultipleChoiceField(choices=prefix_status_choices, required=False)
    site = FilterChoiceField(
        queryset=Site.objects.annotate(filter_count=Count('prefixes')),
        to_field_name='slug',
        null_option=(0, 'None')
    )
    role = FilterChoiceField(
        queryset=Role.objects.annotate(filter_count=Count('prefixes')),
        to_field_name='slug',
        null_option=(0, 'None')
    )
    expand = forms.BooleanField(required=False, label='Expand prefix hierarchy')


#
# IP addresses
#

class IPAddressForm(BootstrapMixin, TenancyForm, ReturnURLForm, CustomFieldForm):
    interface_site = forms.ModelChoiceField(
        queryset=Site.objects.all(),
        required=False,
        label='Site',
        widget=forms.Select(
            attrs={'filter-for': 'interface_rack'}
        )
    )
    interface_rack = ChainedModelChoiceField(
        queryset=Rack.objects.all(),
        chains={'site': 'interface_site'},
        required=False,
        label='Rack',
        widget=APISelect(
            api_url='/api/dcim/racks/?site_id={{interface_site}}',
            display_field='display_name',
            attrs={'filter-for': 'interface_device', 'nullable': 'true'}
        )
    )
    interface_device = ChainedModelChoiceField(
        queryset=Device.objects.all(),
        chains={'site': 'interface_site', 'rack': 'interface_rack'},
        required=False,
        label='Device',
        widget=APISelect(
            api_url='/api/dcim/devices/?site_id={{interface_site}}&rack_id={{interface_rack}}',
            display_field='display_name',
            attrs={'filter-for': 'interface'}
        )
    )
    interface = ChainedModelChoiceField(
        queryset=Interface.objects.all(),
        chains={'device': 'interface_device'},
        required=False,
        widget=APISelect(
            api_url='/api/dcim/interfaces/?device_id={{interface_device}}'
        )
    )
    nat_site = forms.ModelChoiceField(
        queryset=Site.objects.all(),
        required=False,
        label='Site',
        widget=forms.Select(
            attrs={'filter-for': 'nat_device'}
        )
    )
    nat_rack = ChainedModelChoiceField(
        queryset=Rack.objects.all(),
        chains={'site': 'nat_site'},
        required=False,
        label='Rack',
        widget=APISelect(
            api_url='/api/dcim/racks/?site_id={{interface_site}}',
            display_field='display_name',
            attrs={'filter-for': 'nat_device', 'nullable': 'true'}
        )
    )
    nat_device = ChainedModelChoiceField(
        queryset=Device.objects.all(),
        chains={'site': 'nat_site'},
        required=False,
        label='Device',
        widget=APISelect(
            api_url='/api/dcim/devices/?site_id={{nat_site}}',
            display_field='display_name',
            attrs={'filter-for': 'nat_inside'}
        )
    )
    nat_inside = ChainedModelChoiceField(
        queryset=IPAddress.objects.all(),
        chains={'interface__device': 'nat_device'},
        required=False,
        label='IP Address',
        widget=APISelect(
            api_url='/api/ipam/ip-addresses/?device_id={{nat_device}}',
            display_field='address'
        )
    )
    livesearch = forms.CharField(
        required=False,
        label='IP Address',
        widget=Livesearch(
            query_key='q',
            query_url='ipam-api:ipaddress-list',
            field_to_update='nat_inside',
            obj_label='address'
        )
    )
    primary_for_device = forms.BooleanField(required=False, label='Make this the primary IP for the device')

    class Meta:
        model = IPAddress
        fields = [
            'address', 'vrf', 'status', 'description', 'interface', 'primary_for_device', 'nat_inside', 'tenant_group',
            'tenant',
        ]

    def __init__(self, instance=None, initial=None, *args, **kwargs):

        # Initialize interface selectors
        if instance and instance.interface is not None:
            initial['interface_site'] = instance.interface.device.site
            initial['interface_rack'] = instance.interface.device.rack
            initial['interface_device'] = instance.interface.device

        # Initialize NAT selectors
        if instance and instance.nat_inside is not None:
            initial['nat_site'] = instance.nat_inside.device.site
            initial['nat_rack'] = instance.nat_inside.device.rack
            initial['nat_device'] = instance.nat_inside.device

        super(IPAddressForm, self).__init__(instance=instance, initial=initial, *args, **kwargs)

        self.fields['vrf'].empty_label = 'Global'

        # Initialize primary_for_device if IP address is already assigned
        if self.instance.interface is not None:
            device = self.instance.interface.device
            if (
                self.instance.address.version == 4 and device.primary_ip4 == self.instance or
                self.instance.address.version == 6 and device.primary_ip6 == self.instance
            ):
                self.initial['primary_for_device'] = True

    def clean(self):
        super(IPAddressForm, self).clean()

        # Primary IP assignment is only available if an interface has been assigned.
        if self.cleaned_data.get('primary_for_device') and not self.cleaned_data.get('interface'):
            self.add_error(
                'primary_for_device', "Only IP addresses assigned to an interface can be designated as primary IPs."
            )

    def save(self, *args, **kwargs):

        ipaddress = super(IPAddressForm, self).save(*args, **kwargs)

        # Assign this IPAddress as the primary for the associated Device.
        if self.cleaned_data['primary_for_device']:
            device = self.cleaned_data['interface'].device
            if ipaddress.address.version == 4:
                device.primary_ip4 = ipaddress
            else:
                device.primary_ip6 = ipaddress
            device.save()

        # Clear assignment as primary for device if set.
        else:
            try:
                if ipaddress.address.version == 4:
                    device = ipaddress.primary_ip4_for
                    device.primary_ip4 = None
                else:
                    device = ipaddress.primary_ip6_for
                    device.primary_ip6 = None
                device.save()
            except Device.DoesNotExist:
                pass

        return ipaddress


class IPAddressBulkAddForm(BootstrapMixin, CustomFieldForm):
    address_pattern = ExpandableIPAddressField(label='Address Pattern')
    vrf = forms.ModelChoiceField(queryset=VRF.objects.all(), required=False, label='VRF', empty_label='Global')

    pattern_map = ('address_pattern', 'address')

    class Meta:
        model = IPAddress
        fields = ['address_pattern', 'vrf', 'tenant', 'status', 'description']


class IPAddressFromCSVForm(forms.ModelForm):
    vrf = forms.ModelChoiceField(queryset=VRF.objects.all(), required=False, to_field_name='rd',
                                 error_messages={'invalid_choice': 'VRF not found.'})
    tenant = forms.ModelChoiceField(Tenant.objects.all(), to_field_name='name', required=False,
                                    error_messages={'invalid_choice': 'Tenant not found.'})
    status_name = forms.ChoiceField(choices=[(s[1], s[0]) for s in IPADDRESS_STATUS_CHOICES])
    device = forms.ModelChoiceField(queryset=Device.objects.all(), required=False, to_field_name='name',
                                    error_messages={'invalid_choice': 'Device not found.'})
    interface_name = forms.CharField(required=False)
    is_primary = forms.BooleanField(required=False)

    class Meta:
        model = IPAddress
        fields = ['address', 'vrf', 'tenant', 'status_name', 'device', 'interface_name', 'is_primary', 'description']

    def clean(self):

        device = self.cleaned_data.get('device')
        interface_name = self.cleaned_data.get('interface_name')
        is_primary = self.cleaned_data.get('is_primary')

        # Validate interface
        if device and interface_name:
            try:
                Interface.objects.get(device=device, name=interface_name)
            except Interface.DoesNotExist:
                self.add_error('interface_name', "Invalid interface ({}) for {}".format(interface_name, device))
        elif device and not interface_name:
            self.add_error('interface_name', "Device set ({}) but interface missing".format(device))
        elif interface_name and not device:
            self.add_error('device', "Interface set ({}) but device missing or invalid".format(interface_name))

        # Validate is_primary
        if is_primary and not device:
            self.add_error('is_primary', "No device specified; cannot set as primary IP")

    def save(self, *args, **kwargs):

        # Assign status by name
        self.instance.status = dict(self.fields['status_name'].choices)[self.cleaned_data['status_name']]

        # Set interface
        if self.cleaned_data['device'] and self.cleaned_data['interface_name']:
            self.instance.interface = Interface.objects.get(device=self.cleaned_data['device'],
                                                            name=self.cleaned_data['interface_name'])
        # Set as primary for device
        if self.cleaned_data['is_primary']:
            if self.instance.address.version == 4:
                self.instance.primary_ip4_for = self.cleaned_data['device']
            elif self.instance.address.version == 6:
                self.instance.primary_ip6_for = self.cleaned_data['device']

        return super(IPAddressFromCSVForm, self).save(*args, **kwargs)


class IPAddressImportForm(BootstrapMixin, BulkImportForm):
    csv = CSVDataField(csv_form=IPAddressFromCSVForm)


class IPAddressBulkEditForm(BootstrapMixin, CustomFieldBulkEditForm):
    pk = forms.ModelMultipleChoiceField(queryset=IPAddress.objects.all(), widget=forms.MultipleHiddenInput)
    vrf = forms.ModelChoiceField(queryset=VRF.objects.all(), required=False, label='VRF')
    tenant = forms.ModelChoiceField(queryset=Tenant.objects.all(), required=False)
    status = forms.ChoiceField(choices=add_blank_choice(IPADDRESS_STATUS_CHOICES), required=False)
    description = forms.CharField(max_length=100, required=False)

    class Meta:
        nullable_fields = ['vrf', 'tenant', 'description']


def ipaddress_status_choices():
    status_counts = {}
    for status in IPAddress.objects.values('status').annotate(count=Count('status')).order_by('status'):
        status_counts[status['status']] = status['count']
    return [(s[0], u'{} ({})'.format(s[1], status_counts.get(s[0], 0))) for s in IPADDRESS_STATUS_CHOICES]


class IPAddressFilterForm(BootstrapMixin, CustomFieldFilterForm):
    model = IPAddress
    q = forms.CharField(required=False, label='Search')
    parent = forms.CharField(required=False, label='Parent Prefix', widget=forms.TextInput(attrs={
        'placeholder': 'Prefix',
    }))
    family = forms.ChoiceField(required=False, choices=IP_FAMILY_CHOICES, label='Address family')
    mask_length = forms.ChoiceField(required=False, choices=IPADDRESS_MASK_LENGTH_CHOICES, label='Mask length')
    vrf = FilterChoiceField(
        queryset=VRF.objects.annotate(filter_count=Count('ip_addresses')),
        to_field_name='rd',
        label='VRF',
        null_option=(0, 'Global')
    )
    tenant = FilterChoiceField(
        queryset=Tenant.objects.annotate(filter_count=Count('ip_addresses')),
        to_field_name='slug',
        null_option=(0, 'None')
    )
    status = forms.MultipleChoiceField(choices=ipaddress_status_choices, required=False)


#
# VLAN groups
#

class VLANGroupForm(BootstrapMixin, forms.ModelForm):
    slug = SlugField()

    class Meta:
        model = VLANGroup
        fields = ['site', 'name', 'slug']


class VLANGroupFilterForm(BootstrapMixin, forms.Form):
    site = FilterChoiceField(
        queryset=Site.objects.annotate(filter_count=Count('vlan_groups')),
        to_field_name='slug',
        null_option=(0, 'Global')
    )


#
# VLANs
#

class VLANForm(BootstrapMixin, TenancyForm, CustomFieldForm):
    site = forms.ModelChoiceField(
        queryset=Site.objects.all(),
        widget=forms.Select(
            attrs={'filter-for': 'group', 'nullable': 'true'}
        )
    )
    group = ChainedModelChoiceField(
        queryset=VLANGroup.objects.all(),
        chains={'site': 'site'},
        required=False,
        label='Group',
        widget=APISelect(
            api_url='/api/ipam/vlan-groups/?site_id={{site}}',
        )
    )

    class Meta:
        model = VLAN
        fields = ['site', 'group', 'vid', 'name', 'status', 'role', 'description', 'tenant_group', 'tenant']
        help_texts = {
            'site': "Leave blank if this VLAN spans multiple sites",
            'group': "VLAN group (optional)",
            'vid': "Configured VLAN ID",
            'name': "Configured VLAN name",
            'status': "Operational status of this VLAN",
            'role': "The primary function of this VLAN",
        }


class VLANFromCSVForm(forms.ModelForm):
    site = forms.ModelChoiceField(
        queryset=Site.objects.all(), required=False, to_field_name='name',
        error_messages={'invalid_choice': 'Site not found.'}
    )
    group_name = forms.CharField(required=False)
    tenant = forms.ModelChoiceField(
        Tenant.objects.all(), to_field_name='name', required=False,
        error_messages={'invalid_choice': 'Tenant not found.'}
    )
    status_name = forms.ChoiceField(choices=[(s[1], s[0]) for s in VLAN_STATUS_CHOICES])
    role = forms.ModelChoiceField(
        queryset=Role.objects.all(), required=False, to_field_name='name',
        error_messages={'invalid_choice': 'Invalid role.'}
    )

    class Meta:
        model = VLAN
        fields = ['site', 'group_name', 'vid', 'name', 'tenant', 'status_name', 'role', 'description']

    def clean(self):

        super(VLANFromCSVForm, self).clean()

        # Validate VLANGroup
        group_name = self.cleaned_data.get('group_name')
        if group_name:
            try:
                VLANGroup.objects.get(site=self.cleaned_data.get('site'), name=group_name)
            except VLANGroup.DoesNotExist:
                self.add_error('group_name', "Invalid VLAN group {}.".format(group_name))

    def save(self, *args, **kwargs):

        vlan = super(VLANFromCSVForm, self).save(commit=False)

        # Assign VLANGroup by site and name
        if self.cleaned_data['group_name']:
            vlan.group = VLANGroup.objects.get(site=self.cleaned_data['site'], name=self.cleaned_data['group_name'])

        # Assign VLAN status by name
        vlan.status = dict(self.fields['status_name'].choices)[self.cleaned_data['status_name']]

        if kwargs.get('commit'):
            vlan.save()
        return vlan


class VLANImportForm(BootstrapMixin, BulkImportForm):
    csv = CSVDataField(csv_form=VLANFromCSVForm)


class VLANBulkEditForm(BootstrapMixin, CustomFieldBulkEditForm):
    pk = forms.ModelMultipleChoiceField(queryset=VLAN.objects.all(), widget=forms.MultipleHiddenInput)
    site = forms.ModelChoiceField(queryset=Site.objects.all(), required=False)
    group = forms.ModelChoiceField(queryset=VLANGroup.objects.all(), required=False)
    tenant = forms.ModelChoiceField(queryset=Tenant.objects.all(), required=False)
    status = forms.ChoiceField(choices=add_blank_choice(VLAN_STATUS_CHOICES), required=False)
    role = forms.ModelChoiceField(queryset=Role.objects.all(), required=False)
    description = forms.CharField(max_length=100, required=False)

    class Meta:
        nullable_fields = ['group', 'tenant', 'role', 'description']


def vlan_status_choices():
    status_counts = {}
    for status in VLAN.objects.values('status').annotate(count=Count('status')).order_by('status'):
        status_counts[status['status']] = status['count']
    return [(s[0], u'{} ({})'.format(s[1], status_counts.get(s[0], 0))) for s in VLAN_STATUS_CHOICES]


class VLANFilterForm(BootstrapMixin, CustomFieldFilterForm):
    model = VLAN
    q = forms.CharField(required=False, label='Search')
    site = FilterChoiceField(
        queryset=Site.objects.annotate(filter_count=Count('vlans')),
        to_field_name='slug',
        null_option=(0, 'Global')
    )
    group_id = FilterChoiceField(
        queryset=VLANGroup.objects.annotate(filter_count=Count('vlans')),
        label='VLAN group',
        null_option=(0, 'None')
    )
    tenant = FilterChoiceField(
        queryset=Tenant.objects.annotate(filter_count=Count('vlans')),
        to_field_name='slug',
        null_option=(0, 'None')
    )
    status = forms.MultipleChoiceField(choices=vlan_status_choices, required=False)
    role = FilterChoiceField(
        queryset=Role.objects.annotate(filter_count=Count('vlans')),
        to_field_name='slug',
        null_option=(0, 'None')
    )


#
# Services
#

class ServiceForm(BootstrapMixin, forms.ModelForm):

    class Meta:
        model = Service
        fields = ['name', 'protocol', 'port', 'ipaddresses', 'description']
        help_texts = {
            'ipaddresses': "IP address assignment is optional. If no IPs are selected, the service is assumed to be "
                           "reachable via all IPs assigned to the device.",
        }

    def __init__(self, *args, **kwargs):

        super(ServiceForm, self).__init__(*args, **kwargs)

        # Limit IP address choices to those assigned to interfaces of the parent device
        self.fields['ipaddresses'].queryset = IPAddress.objects.filter(interface__device=self.instance.device)