from decimal import Decimal

from django.urls import resolve, reverse
from django.dispatch import receiver
from django.http import HttpRequest
from django.utils.translation import ugettext_lazy as _
from pretix.base.models import Event, Order, TaxRule
from pretix.base.models.orders import OrderFee
from pretix.base.signals import order_fee_calculation
from pretix.control.signals import nav_event_settings
from pretix.presale.signals import fee_calculation_for_cart


@receiver(nav_event_settings, dispatch_uid='service_fee_nav_settings')
def navbar_settings(sender, request, **kwargs):
    url = resolve(request.path_info)
    return [{
        'label': _('Service Fee'),
        'url': reverse('plugins:pretix_servicefees:settings', kwargs={
            'event': request.event.slug,
            'organizer': request.organizer.slug,
        }),
        'active': url.namespace == 'plugins:pretix_servicefees' and url.url_name.startswith('settings'),
    }]


def get_fees(event, total, invoice_address):
    fee = event.settings.get('service_fee_abs', as_type=Decimal)
    if fee and total != Decimal('0.00'):
        tax_rule = event.settings.tax_rate_default or TaxRule.zero()
        if tax_rule.tax_applicable(invoice_address):
            tax = tax_rule.tax(fee)
            return [OrderFee(
                fee_type=OrderFee.FEE_TYPE_SERVICE,
                internal_type='',
                value=fee,
                tax_rate=tax.rate,
                tax_value=tax.tax,
                tax_rule=tax_rule
            )]
        else:
            return [OrderFee(
                fee_type=OrderFee.FEE_TYPE_SERVICE,
                internal_type='',
                value=fee,
                tax_rate=Decimal('0.00'),
                tax_value=Decimal('0.00'),
                tax_rule=tax_rule
            )]
    return []


@receiver(fee_calculation_for_cart, dispatch_uid="service_fee_calc_cart")
def cart_fee(sender: Event, request: HttpRequest, invoice_address, total, **kwargs):
    return get_fees(sender, total, invoice_address)


@receiver(order_fee_calculation, dispatch_uid="service_fee_calc_order")
def order_fee(sender: Event, invoice_address, total, **kwargs):
    return get_fees(sender, total, invoice_address)