#
# This file is part of pretix (Community Edition).
#
# Copyright (C) 2014-2020 Raphael Michel and contributors
# Copyright (C) 2020-2021 rami.io GmbH and contributors
#
# This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General
# Public License as published by the Free Software Foundation in version 3 of the License.
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# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
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# this file, see <https://pretix.eu/about/en/license>.
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# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
# details.
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# You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
# <https://www.gnu.org/licenses/>.
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# This file is based on an earlier version of pretix which was released under the Apache License 2.0. The full text of
# the Apache License 2.0 can be obtained at <http://www.apache.org/licenses/LICENSE-2.0>.
#
# This file may have since been changed and any changes are released under the terms of AGPLv3 as described above. A
# full history of changes and contributors is available at <https://github.com/pretix/pretix>.
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# This file contains Apache-licensed contributions copyrighted by: pajowu
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# Unless required by applicable law or agreed to in writing, software distributed under the Apache License 2.0 is
# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations under the License.

import copy
import json
from collections import OrderedDict
from datetime import datetime, time, timedelta
from io import BytesIO
from typing import Tuple

import dateutil.parser
from django import forms
from django.contrib.staticfiles import finders
from django.core.files import File
from django.core.files.storage import default_storage
from django.db.models import Exists, OuterRef, Q
from django.db.models.functions import Coalesce
from django.utils.timezone import make_aware
from django.utils.translation import gettext as _, gettext_lazy
from reportlab.lib import pagesizes
from reportlab.lib.units import mm
from reportlab.pdfgen import canvas

from pretix.base.exporter import BaseExporter
from pretix.base.i18n import language
from pretix.base.models import Order, OrderPosition
from pretix.base.pdf import Renderer
from pretix.base.services.orders import OrderError
from pretix.base.settings import PERSON_NAME_SCHEMES
from pretix.helpers.templatetags.jsonfield import JSONExtract
from pretix.plugins.badges.models import BadgeItem, BadgeLayout


def _renderer(event, layout):
    if layout is None:
        return None
    if isinstance(layout.background, File) and layout.background.name:
        bgf = default_storage.open(layout.background.name, "rb")
    else:
        bgf = open(finders.find('pretixplugins/badges/badge_default_a6l.pdf'), "rb")
    return Renderer(event, json.loads(layout.layout), bgf)


OPTIONS = OrderedDict([
    ('one', {
        'name': gettext_lazy('One badge per page'),
        'cols': 1,
        'rows': 1,
        'margins': [0, 0, 0, 0],
        'offsets': [0, 0],
        'pagesize': None,
    }),
    ('a4_a6l', {
        'name': gettext_lazy('4 landscape A6 pages on one A4 page'),
        'cols': 2,
        'rows': 2,
        'margins': [0 * mm, 0 * mm, 0 * mm, 0 * mm],
        'offsets': [pagesizes.landscape(pagesizes.A4)[0] / 2, pagesizes.landscape(pagesizes.A4)[1] / 2],
        'pagesize': pagesizes.landscape(pagesizes.A4),
    }),
    ('a4_a6p', {
        'name': gettext_lazy('4 portrait A6 pages on one A4 page'),
        'cols': 2,
        'rows': 2,
        'margins': [0 * mm, 0 * mm, 0 * mm, 0 * mm],
        'offsets': [pagesizes.portrait(pagesizes.A4)[0] / 2, pagesizes.portrait(pagesizes.A4)[0] / 2],
        'pagesize': pagesizes.portrait(pagesizes.A4),
    }),
    ('a4_a7l', {
        'name': gettext_lazy('8 landscape A7 pages on one A4 page'),
        'cols': 2,
        'rows': 4,
        'margins': [0 * mm, 0 * mm, 0 * mm, 0 * mm],
        'offsets': [pagesizes.portrait(pagesizes.A4)[0] / 2, pagesizes.portrait(pagesizes.A4)[1] / 4],
        'pagesize': pagesizes.portrait(pagesizes.A4),
    }),
    ('a4_a7p', {
        'name': gettext_lazy('8 portrait A7 pages on one A4 page'),
        'cols': 4,
        'rows': 2,
        'margins': [0 * mm, 0 * mm, 0 * mm, 0 * mm],
        'offsets': [pagesizes.landscape(pagesizes.A4)[0] / 4, pagesizes.landscape(pagesizes.A4)[0] / 2],
        'pagesize': pagesizes.landscape(pagesizes.A4),
    }),
    ('durable_54x90', {
        'name': 'DURABLE BADGEMAKER® 54 x 90 mm (1445-02)',
        'cols': 2,
        'rows': 5,
        'margins': [12 * mm, 15 * mm, 15 * mm, 15 * mm],
        'offsets': [90 * mm, 54 * mm],
        'pagesize': pagesizes.A4,
    }),
    ('durable_40x75', {
        'name': 'DURABLE BADGEMAKER® 40 x 75 mm (1453-02)',
        'cols': 2,
        'rows': 6,
        'margins': [28.5 * mm, 30 * mm, 28.5 * mm, 30 * mm],
        'offsets': [75 * mm, 40 * mm],
        'pagesize': pagesizes.A4,
    }),
    ('durable_60x90', {
        'name': 'DURABLE BADGEMAKER® 60 x 90 mm (1456-02)',
        'cols': 2,
        'rows': 4,
        'margins': [28.5 * mm, 15 * mm, 28.5 * mm, 15 * mm],
        'offsets': [90 * mm, 60 * mm],
        'pagesize': pagesizes.A4,
    }),
    ('durable_fix_40x75', {
        'name': 'DURABLE BADGEFIX® 40 x 75 mm (8334-02)',
        'cols': 2,
        'rows': 6,
        'margins': [28.5 * mm, 30 * mm, 28.5 * mm, 30 * mm],
        'offsets': [93 * mm, 60 * mm],
        'pagesize': pagesizes.A4,
    }),
    ('herma_50x80', {
        'name': 'HERMA 50 x 80 mm (4412)',
        'cols': 2,
        'rows': 5,
        'margins': [13.5 * mm, 17.5 * mm, 13.5 * mm, 17.5 * mm],
        'offsets': [95 * mm, 55 * mm],
        'pagesize': pagesizes.A4,
    }),
])


def render_pdf(event, positions, opt):
    from PyPDF2 import PdfFileReader, PdfFileWriter
    Renderer._register_fonts()

    renderermap = {
        bi.item_id: _renderer(event, bi.layout)
        for bi in BadgeItem.objects.select_related('layout').filter(item__event=event)
    }
    try:
        default_renderer = _renderer(event, event.badge_layouts.get(default=True))
    except BadgeLayout.DoesNotExist:
        default_renderer = None
    output_pdf_writer = PdfFileWriter()

    any = False
    npp = opt['cols'] * opt['rows']

    def render_page(positions):
        buffer = BytesIO()
        p = canvas.Canvas(buffer, pagesize=pagesizes.A4)
        for i, (op, r) in enumerate(positions):
            offsetx = opt['margins'][3] + (i % opt['cols']) * opt['offsets'][0]
            offsety = opt['margins'][2] + (opt['rows'] - 1 - i // opt['cols']) * opt['offsets'][1]
            p.translate(offsetx, offsety)
            with language(op.order.locale, op.order.event.settings.region):
                r.draw_page(p, op.order, op, show_page=False, only_page=1)
            p.translate(-offsetx, -offsety)

        if opt['pagesize']:
            p.setPageSize(opt['pagesize'])
        p.showPage()
        p.save()
        buffer.seek(0)
        canvas_pdf_reader = PdfFileReader(buffer)
        empty_pdf_page = output_pdf_writer.addBlankPage(
            width=opt['pagesize'][0] if opt['pagesize'] else positions[0][1].bg_pdf.getPage(0).mediaBox[2],
            height=opt['pagesize'][1] if opt['pagesize'] else positions[0][1].bg_pdf.getPage(0).mediaBox[3],
        )
        for i, (op, r) in enumerate(positions):
            bg_page = copy.copy(r.bg_pdf.getPage(0))
            offsetx = opt['margins'][3] + (i % opt['cols']) * opt['offsets'][0]
            offsety = opt['margins'][2] + (opt['rows'] - 1 - i // opt['cols']) * opt['offsets'][1]
            empty_pdf_page.mergeTranslatedPage(
                bg_page,
                tx=offsetx,
                ty=offsety
            )
        empty_pdf_page.mergePage(canvas_pdf_reader.getPage(0))

    pagebuffer = []
    outbuffer = BytesIO()
    for op in positions:
        r = renderermap.get(op.item_id, default_renderer)
        if not r:
            continue
        any = True
        pagebuffer.append((op, r))
        if len(pagebuffer) == npp:
            render_page(pagebuffer)
            pagebuffer.clear()

    if pagebuffer:
        render_page(pagebuffer)

    output_pdf_writer.addMetadata({
        '/Title': 'Badges',
        '/Creator': 'pretix',
    })
    output_pdf_writer.write(outbuffer)
    outbuffer.seek(0)
    if not any:
        raise OrderError(_("None of the selected products is configured to print badges."))
    return outbuffer


class BadgeExporter(BaseExporter):
    identifier = "badges"
    verbose_name = _("Attendee badges")

    @property
    def export_form_fields(self):
        name_scheme = PERSON_NAME_SCHEMES[self.event.settings.name_scheme]
        d = OrderedDict(
            [
                ('items',
                 forms.ModelMultipleChoiceField(
                     queryset=self.event.items.annotate(
                         no_badging=Exists(BadgeItem.objects.filter(item=OuterRef('pk'), layout__isnull=True))
                     ).exclude(no_badging=True),
                     label=_('Limit to products'),
                     widget=forms.CheckboxSelectMultiple(
                         attrs={'class': 'scrolling-multiple-choice'}
                     ),
                     initial=self.event.items.filter(admission=True)
                 )),
                ('include_pending',
                 forms.BooleanField(
                     label=_('Include pending orders'),
                     required=False
                 )),
                ('include_addons',
                 forms.BooleanField(
                     label=_('Include add-on or bundled positions'),
                     required=False
                 )),
                ('rendering',
                 forms.ChoiceField(
                     label=_('Rendering option'),
                     choices=[
                         (k, r['name']) for k, r in OPTIONS.items()
                     ],
                     required=True,
                     help_text=_('This option allows you to align multiple badges on one page, for example if you '
                                 'want to print to a sheet of stickers with a regular office printer. Please note '
                                 'that your individual badge layouts must already be in the correct size.')
                 )),
                ('date_from',
                 forms.DateField(
                     label=_('Start date'),
                     widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
                     required=False,
                     help_text=_('Only include tickets for dates on or after this date.')
                 )),
                ('date_to',
                 forms.DateField(
                     label=_('End date'),
                     widget=forms.DateInput(attrs={'class': 'datepickerfield'}),
                     required=False,
                     help_text=_('Only include tickets for dates on or before this date.')
                 )),
                ('order_by',
                 forms.ChoiceField(
                     label=_('Sort by'),
                     choices=[
                         ('name', _('Attendee name')),
                         ('code', _('Order code')),
                         ('date', _('Event date')),
                     ] + ([
                         ('name:{}'.format(k), _('Attendee name: {part}').format(part=label))
                         for k, label, w in name_scheme['fields']
                     ] if len(name_scheme['fields']) > 1 else []),
                 )),
            ]
        )
        return d

    def render(self, form_data: dict) -> Tuple[str, str, str]:
        qs = OrderPosition.objects.filter(
            order__event=self.event, item_id__in=form_data['items']
        ).prefetch_related(
            'answers', 'answers__question'
        ).select_related('order', 'item', 'variation', 'addon_to')

        if not form_data.get('include_addons'):
            qs = qs.filter(addon_to__isnull=True)

        if form_data.get('include_pending'):
            qs = qs.filter(order__status__in=[Order.STATUS_PAID, Order.STATUS_PENDING])
        else:
            qs = qs.filter(order__status__in=[Order.STATUS_PAID])

        if form_data.get('date_from'):
            dt = make_aware(datetime.combine(
                dateutil.parser.parse(form_data['date_from']).date(),
                time(hour=0, minute=0, second=0)
            ), self.event.timezone)
            qs = qs.filter(Q(subevent__date_from__gte=dt) | Q(subevent__isnull=True, order__event__date_from__gte=dt))

        if form_data.get('date_to'):
            dt = make_aware(datetime.combine(
                dateutil.parser.parse(form_data['date_to']).date() + timedelta(days=1),
                time(hour=0, minute=0, second=0)
            ), self.event.timezone)
            qs = qs.filter(Q(subevent__date_from__lt=dt) | Q(subevent__isnull=True, order__event__date_from__lt=dt))

        if form_data.get('order_by') == 'name':
            qs = qs.order_by('attendee_name_cached', 'order__code')
        elif form_data.get('order_by') == 'code':
            qs = qs.order_by('order__code')
        elif form_data.get('order_by') == 'date':
            qs = qs.annotate(ed=Coalesce('subevent__date_from', 'order__event__date_from')).order_by('ed', 'order__code')
        elif form_data.get('order_by', '').startswith('name:'):
            part = form_data['order_by'][5:]
            qs = qs.annotate(
                resolved_name=Coalesce('attendee_name_parts', 'addon_to__attendee_name_parts',
                                       'order__invoice_address__name_parts')
            ).annotate(
                resolved_name_part=JSONExtract('resolved_name', part)
            ).order_by(
                'resolved_name_part'
            )

        outbuffer = render_pdf(self.event, qs, OPTIONS[form_data.get('rendering', 'one')])
        return 'badges.pdf', 'application/pdf', outbuffer.read()