from django.utils.translation import ugettext_lazy as _
from django.contrib.auth.models import Group
from django.db.models import Q
from django.http.request import QueryDict

import django_filters
from django_filters.widgets import LinkWidget
from django_tables2.utils import A
import django_tables2 as tables

from .models import Equipment, EquipmentCategory


class EquipmentFilter(django_filters.FilterSet):
    owner = django_filters.ModelChoiceFilter(
                    field_name='owner',
                    queryset=Group.objects.all(),
                    widget=LinkWidget(),
                    )
    category = django_filters.ModelChoiceFilter(
                    field_name='category',
                    queryset=EquipmentCategory.objects.all(),
                    widget=LinkWidget(),
                    method='filter_category',
                    )

    def filter_category(self, queryset, name, value):
        return queryset.in_category(value)

    def get_categories(self, qs):
        """
        rend les catégories qui servent à filtrer les Equipments de qs
        ie les catégories des equipments et tous leurs parents
        """
        filtre = Q(id__lt=0)
        for eq in qs:
            current = eq.category
            for k in range(100):
                if current is None:
                    break
                filtre |= Q(id=current.id)
                current = current.parent
        return EquipmentCategory.objects.filter(filtre)

    def __init__(self, data=None, queryset=None, *, request=None, prefix=None):
        # On que les requêtes vides rendent quelque chose
        if data is None:
            data = QueryDict('category&owner')
        super().__init__(data=data, queryset=queryset,
                         request=request, prefix=prefix)
        if self.queryset is not None:
            for filter_ in self.filters.values():
                if filter_.queryset.model == Group:
                    own_ids = [eq.owner.id for eq in self.queryset
                               if eq.owner is not None]
                    filtre = Q(id__lt=0)
                    for own_id in own_ids:
                        filtre |= Q(id=own_id)
                    filter_.queryset = Group.objects.filter(filtre)
                if filter_.queryset.model == EquipmentCategory:
                    filter_.queryset = self.get_categories(self.queryset)

    class Meta:
        model = Equipment
        fields = ['category', 'owner']


class AbstractEquipmentTable(tables.Table):
    stock_aviable_p = tables.Column(
                        accessor=A('stock_aviable_p'),
                        orderable=False,  # TODO le rendre ordorable
                        verbose_name=_("Quantité disponible"),
                        )
    full_category_p = tables.Column(
                        accessor=A('full_category_p'),
                        order_by=('category'),
                        verbose_name=_("Catégorie"),
                        )
    name = tables.LinkColumn(
                        'equipment:detail',
                        args=[A('pk')],
                        verbose_name=_("Matériel"),
                        )
    admin = tables.LinkColumn(
                        'admin:equipment_equipment_change',
                        attrs={
                                'a': {'class': 'glyphicon glyphicon-cog'}
                                },
                        text="",
                        orderable=False,
                        args=[A('pk')],
                        verbose_name=_(""),
                        )

    def before_render(self, request):
        if (request.user.is_staff and
                request.user.has_perm('equipment_change_equipment')):
            self.columns.show('admin')
        else:
            self.columns.hide('admin')


class EquipmentTable(AbstractEquipmentTable):
    class Meta:
        model = Equipment
        template_name = 'equipment/tables/bootstrap-responsive.html'
        fields = ['name', 'stock', 'owner', ]
        sequence = ['admin', 'name', 'stock', 'stock_aviable_p',
                    'full_category_p', 'owner', ]