import copy
import json

from django.dispatch import receiver
from django.urls import reverse
from django.utils.html import escape
from django.utils.translation import ugettext_lazy as _

from pretix.base.channels import get_all_sales_channels
from pretix.base.signals import (  # NOQA: legacy import
    EventPluginSignal, event_copy_data, item_copy_data, layout_text_variables,
    logentry_display, logentry_object_link, register_data_exporters,
    register_ticket_outputs,
)
from pretix.control.signals import item_forms
from pretix.plugins.ticketoutputpdf.forms import TicketLayoutItemForm
from pretix.plugins.ticketoutputpdf.models import (
    TicketLayout, TicketLayoutItem,
)
from pretix.presale.style import (  # NOQA: legacy import
    get_fonts, register_fonts,
)


@receiver(register_ticket_outputs, dispatch_uid="output_pdf")
def register_ticket_outputs(sender, **kwargs):
    from .ticketoutput import PdfTicketOutput
    return PdfTicketOutput


@receiver(register_data_exporters, dispatch_uid="dataexport_pdf")
def register_data(sender, **kwargs):
    from .exporters import AllTicketsPDF
    return AllTicketsPDF


@receiver(item_forms, dispatch_uid="pretix_ticketoutputpdf_item_forms")
def control_item_forms(sender, request, item, **kwargs):
    forms = []
    for k, v in sorted(list(get_all_sales_channels().items()), key=lambda a: (int(a[0] != 'web'), a[0])):
        try:
            inst = TicketLayoutItem.objects.get(item=item, sales_channel=k)
        except TicketLayoutItem.DoesNotExist:
            inst = TicketLayoutItem(item=item)
        forms.append(TicketLayoutItemForm(
            instance=inst,
            event=sender,
            sales_channel=v,
            data=(request.POST if request.method == "POST" else None),
            prefix="ticketlayoutitem_{}".format(k)
        ))
    return forms


@receiver(item_copy_data, dispatch_uid="pretix_ticketoutputpdf_item_copy")
def copy_item(sender, source, target, **kwargs):
    for tli in TicketLayoutItem.objects.filter(item=source):
        TicketLayoutItem.objects.create(item=target, layout=tli.layout, sales_channel=tli.sales_channel)


@receiver(signal=event_copy_data, dispatch_uid="pretix_ticketoutputpdf_copy_data")
def pdf_event_copy_data_receiver(sender, other, item_map, question_map, **kwargs):
    if sender.ticket_layouts.exists():  # idempotency
        return
    layout_map = {}
    for bl in other.ticket_layouts.all():
        oldid = bl.pk
        bl = copy.copy(bl)
        bl.pk = None
        bl.event = sender

        layout = json.loads(bl.layout)
        for o in layout:
            if o['type'] == 'textarea':
                if o['content'].startswith('question_'):
                    newq = question_map.get(int(o['content'][9:]))
                    if newq:
                        o['content'] = 'question_{}'.format(newq.pk)
        bl.layout = json.dumps(layout)

        bl.save()

        if bl.background and bl.background.name:
            bl.background.save('background.pdf', bl.background)

        layout_map[oldid] = bl

    for bi in TicketLayoutItem.objects.filter(item__event=other):
        TicketLayoutItem.objects.create(item=item_map.get(bi.item_id), layout=layout_map.get(bi.layout_id),
                                        sales_channel=bi.sales_channel)
    return layout_map


@receiver(signal=logentry_display, dispatch_uid="pretix_ticketoutputpdf_logentry_display")
def pdf_logentry_display(sender, logentry, **kwargs):
    if not logentry.action_type.startswith('pretix.plugins.ticketoutputpdf'):
        return

    plains = {
        'pretix.plugins.ticketoutputpdf.layout.added': _('Ticket layout created.'),
        'pretix.plugins.ticketoutputpdf.layout.deleted': _('Ticket layout deleted.'),
        'pretix.plugins.ticketoutputpdf.layout.changed': _('Ticket layout changed.'),
    }

    if logentry.action_type in plains:
        return plains[logentry.action_type]


@receiver(signal=logentry_object_link, dispatch_uid="pretix_ticketoutputpdf_logentry_object_link")
def pdf_logentry_object_link(sender, logentry, **kwargs):
    if not logentry.action_type.startswith('pretix.plugins.ticketoutputpdf.layout') or not isinstance(
            logentry.content_object, TicketLayout):
        return

    a_text = _('Ticket layout {val}')
    a_map = {
        'href': reverse('plugins:ticketoutputpdf:edit', kwargs={
            'event': sender.slug,
            'organizer': sender.organizer.slug,
            'layout': logentry.content_object.id
        }),
        'val': escape(logentry.content_object.name),
    }
    a_map['val'] = '<a href="{href}">{val}</a>'.format_map(a_map)
    return a_text.format_map(a_map)


override_layout = EventPluginSignal(
    providing_args=["layout", "orderposition"]
)
"""
This signal allows you to forcefully override the ticket layout that is being used to create the ticket PDF. Use with
care, as this will render any specifically by the organizer selected templates useless.

The ``layout`` keyword argument will contain the layout which has been originally selected by the system, the
``orderposition`` keyword argument will contain the ``OrderPosition`` which is being generated.

If you implement this signal and do not want to override the layout, make sure to return the ``layout`` keyword argument
which you have been passed.

As with all plugin signals, the ``sender`` keyword will contain the event.
"""