from django.contrib import admin
from django.db import models
from django.forms import ModelForm
from django.utils import timezone
from django.core.urlresolvers import reverse
from django.utils.html import format_html

from djadhere.utils import get_active_filter
from banking.models import Payment
from banking.admin import PaymentInline
from .models import Service, ServiceType, IPResource, ResourceAllocation


### Filters

class ResourceInUseFilter(admin.SimpleListFilter):
    title = 'disponibilité'
    parameter_name = 'available'

    def lookups(self, request, model_admin):
        return (
            (1, 'Disponible'),
            (0, 'Non disponible'),
        )

    def queryset(self, request, queryset):
        now = timezone.now()
        active_filter = get_active_filter('allocation')
        if self.value() == '0': # non disponible
            return queryset.filter(active_filter)
        if self.value() == '1': # disponible
            return queryset.exclude(active_filter)


class AllocationStatusFilter(admin.SimpleListFilter):
    title = 'statut'
    parameter_name = 'status'

    def lookups(self, request, model_admin):
        return (
            (1, 'En cours'),
            (0, 'Terminée'),
        )

    def queryset(self, request, queryset):
        now = timezone.now()
        active_filter = get_active_filter()
        if self.value() == '0': # inactif
            return queryset.exclude(active_filter)
        if self.value() == '1': # actif
            return queryset.filter(active_filter)


class ServiceTypeFilter(admin.SimpleListFilter):
    title = 'type de service'
    parameter_name = 'type'

    def lookups(self, request, model_admin):
        return ServiceType.objects.values_list('pk', 'name')

    def queryset(self, request, queryset):
        if self.value():
            return queryset.filter(service_type__pk=self.value())


### Helpers

def get_foreignkey_link_func(field):
    def foreignkey_link(self, instance):
        obj = getattr(instance, field)
        url = reverse('admin:%s_%s_change' % (obj._meta.app_label,  
                                                obj._meta.model_name),
                        args=(obj.id,))
        return format_html(u'<a href="{}">{}</a>', url, str(obj))
    return foreignkey_link


### Inlines

class AllocationInline(admin.TabularInline):
    model = ResourceAllocation
    extra = 0
    fields = ('id', 'service', 'resource', 'start', 'end')
    raw_id_fields = ('service', 'resource',)
    verbose_name_plural = 'Allocations'


### Actions

def ends_resource(resource, request, queryset):
    now = timezone.now()
    queryset.exclude(start__lte=now, end__isnull=False).update(end=now)
ends_resource.short_description = 'Terminer les allocations sélectionnées'


### ModelAdmin

class ServiceAdmin(admin.ModelAdmin):
    list_display = ('id', 'adhesion', 'service_type', 'label', 'active')
    list_filter = ('active', ServiceTypeFilter,)
    inlines = (PaymentInline, AllocationInline,)
    search_fields = ('id', 'service_type__name', 'label')
    raw_id_fields = ('adhesion',)


class IPResourceAdmin(admin.ModelAdmin):
    list_display = ('__str__', 'in_use_display')
    list_filter = (ResourceInUseFilter,)
    fields =('ip', 'mask',)
    search_fields = ('ip',)
    inlines = (AllocationInline,)

    def in_use_display(self, obj):
        return not obj.in_use
    in_use_display.short_description = 'Disponible'
    in_use_display.boolean = True


class ResourceAllocationAdmin(admin.ModelAdmin):
    list_display = ('id', 'resource_link', 'service_link', 'start', 'end',)
    list_filter = (AllocationStatusFilter,)
    actions = (ends_resource,)
    raw_id_fields = ('service',)
    search_fields = ('resource__ip', 'service__id', 'service__service_type__name', 'service__label')

    resource_link = get_foreignkey_link_func('resource')
    resource_link.short_description = 'Ressource'

    service_link = get_foreignkey_link_func('service')
    service_link.short_description = 'Service'


admin.site.register(ServiceType)
admin.site.register(Service, ServiceAdmin)
admin.site.register(IPResource, IPResourceAdmin)
admin.site.register(ResourceAllocation, ResourceAllocationAdmin)