import os
import tempfile
from collections import OrderedDict
from zipfile import ZipFile

import dateutil.parser
from django import forms
from django.db.models import Exists, OuterRef, Q
from django.dispatch import receiver
from django.utils.translation import ugettext_lazy as _

from pretix.base.models import OrderPayment

from ..exporter import BaseExporter
from ..services.invoices import invoice_pdf_task
from ..signals import register_data_exporters


class InvoiceExporter(BaseExporter):
    identifier = 'invoices'
    verbose_name = _('All invoices')

    def render(self, form_data: dict, output_file=None):
        qs = self.event.invoices.filter(shredded=False)

        if form_data.get('payment_provider'):
            qs = qs.annotate(
                has_payment_with_provider=Exists(
                    OrderPayment.objects.filter(
                        Q(order=OuterRef('order_id')) & Q(provider=form_data.get('payment_provider'))
                    )
                )
            )
            qs = qs.filter(has_payment_with_provider=1)

        if form_data.get('date_from'):
            date_value = form_data.get('date_from')
            if isinstance(date_value, str):
                date_value = dateutil.parser.parse(date_value).date()
            qs = qs.filter(date__gte=date_value)

        if form_data.get('date_to'):
            date_value = form_data.get('date_to')
            if isinstance(date_value, str):
                date_value = dateutil.parser.parse(date_value).date()
            qs = qs.filter(date__lte=date_value)

        with tempfile.TemporaryDirectory() as d:
            any = False
            with ZipFile(output_file or os.path.join(d, 'tmp.zip'), 'w') as zipf:
                for i in qs:
                    try:
                        if not i.file:
                            invoice_pdf_task.apply(args=(i.pk,))
                            i.refresh_from_db()
                        i.file.open('rb')
                        zipf.writestr('{}.pdf'.format(i.number), i.file.read())
                        any = True
                        i.file.close()
                    except FileNotFoundError:
                        invoice_pdf_task.apply(args=(i.pk,))
                        i.refresh_from_db()
                        i.file.open('rb')
                        zipf.writestr('{}.pdf'.format(i.number), i.file.read())
                        any = True
                        i.file.close()

            if not any:
                return None

            if output_file:
                return '{}_invoices.zip'.format(self.event.slug), 'application/zip', None
            else:
                with open(os.path.join(d, 'tmp.zip'), 'rb') as zipf:
                    return '{}_invoices.zip'.format(self.event.slug), 'application/zip', zipf.read()

    @property
    def export_form_fields(self):
        return OrderedDict(
            [
                ('date_from',
                 forms.DateField(
                     label=_('Start date'),
                     widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
                     required=False,
                     help_text=_('Only include invoices issued on or after this date. Note that the invoice date does '
                                 'not always correspond to the order or payment date.')
                 )),
                ('date_to',
                 forms.DateField(
                     label=_('End date'),
                     widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
                     required=False,
                     help_text=_('Only include invoices issued on or before this date. Note that the invoice date '
                                 'does not always correspond to the order or payment date.')
                 )),
                ('payment_provider',
                 forms.ChoiceField(
                     label=_('Payment provider'),
                     choices=[
                         ('', _('All payment providers')),
                     ] + [
                         (k, v.verbose_name) for k, v in self.event.get_payment_providers().items()
                     ],
                     required=False,
                     help_text=_('Only include invoices for orders that have at least one payment attempt '
                                 'with this payment provider. '
                                 'Note that this might include some invoices of orders which in the end have been '
                                 'fully or partially paid with a different provider.')
                 )),
            ]
        )


@receiver(register_data_exporters, dispatch_uid="exporter_invoices")
def register_invoice_export(sender, **kwargs):
    return InvoiceExporter