#
# 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.
#
# ADDITIONAL TERMS APPLY: Pursuant to Section 7 of the GNU Affero General Public License, additional terms are
# applicable granting you additional permissions and placing additional restrictions on your usage of this software.
# Please refer to the pretix LICENSE file to obtain the full terms applicable to this work. If you did not receive
# this file, see <https://pretix.eu/about/en/license>.
#
# This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more
# details.
#
# 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/>.
#
import json
from decimal import Decimal

import pytest
from django.utils import translation
from django.utils.timezone import now
from django_countries.fields import Country

from pretix.base.decimal import round_decimal
from pretix.base.models import Event, InvoiceAddress, Organizer
from pretix.base.models.items import SubEventItem, SubEventItemVariation
from pretix.base.services.pricing import get_price


@pytest.fixture
def event():
    o = Organizer.objects.create(name='Dummy', slug='dummy')
    event = Event.objects.create(
        organizer=o, name='Dummy', slug='dummy',
        date_from=now()
    )
    return event


@pytest.fixture
def item(event):
    return event.items.create(name='Ticket', default_price=Decimal('23.00'))


@pytest.fixture
def variation(item):
    return item.variations.create(value='Premium', default_price=None)


@pytest.fixture
def voucher(event):
    return event.vouchers.create()


@pytest.fixture
def subevent(event):
    event.has_subevents = True
    event.save()
    return event.subevents.create(name='Foobar', date_from=now())


@pytest.mark.django_db
def test_base_item_default(item):
    assert get_price(item).gross == Decimal('23.00')


@pytest.mark.django_db
def test_base_item_subevent_no_entry(item, subevent):
    assert get_price(item, subevent=subevent).gross == Decimal('23.00')


@pytest.mark.django_db
def test_base_item_subevent_no_override(item, subevent):
    SubEventItem.objects.create(item=item, subevent=subevent, price=None)
    assert get_price(item, subevent=subevent).gross == Decimal('23.00')


@pytest.mark.django_db
def test_base_item_subevent_override(item, subevent):
    SubEventItem.objects.create(item=item, subevent=subevent, price=Decimal('24.00'))
    assert get_price(item, subevent=subevent).gross == Decimal('24.00')


@pytest.mark.django_db
def test_variation_with_default_item_price(item, variation):
    assert get_price(item, variation=variation).gross == Decimal('23.00')


@pytest.mark.django_db
def test_variation_with_specific_price(item, variation):
    variation.default_price = Decimal('24.00')
    assert get_price(item, variation=variation).gross == Decimal('24.00')


@pytest.mark.django_db
def test_variation_with_default_subevent_and_default_price(item, subevent, variation):
    SubEventItemVariation.objects.create(variation=variation, subevent=subevent, price=None)
    assert get_price(item, variation=variation, subevent=subevent).gross == Decimal('23.00')


@pytest.mark.django_db
def test_variation_with_subevent_and_default_price(item, subevent, variation):
    SubEventItemVariation.objects.create(variation=variation, subevent=subevent, price=Decimal('24.00'))
    assert get_price(item, variation=variation, subevent=subevent).gross == Decimal('24.00')


@pytest.mark.django_db
def test_variation_with_no_subevent_and_specific_price(item, subevent, variation):
    variation.default_price = Decimal('24.00')
    assert get_price(item, variation=variation, subevent=subevent).gross == Decimal('24.00')


@pytest.mark.django_db
def test_variation_with_default_subevent_and_specific_price(item, subevent, variation):
    variation.default_price = Decimal('24.00')
    SubEventItemVariation.objects.create(variation=variation, subevent=subevent, price=None)
    assert get_price(item, variation=variation, subevent=subevent).gross == Decimal('24.00')


@pytest.mark.django_db
def test_variation_with_subevent_and_specific_price(item, subevent, variation):
    variation.default_price = Decimal('24.00')
    SubEventItemVariation.objects.create(variation=variation, subevent=subevent, price=Decimal('26.00'))
    assert get_price(item, variation=variation, subevent=subevent).gross == Decimal('26.00')


@pytest.mark.django_db
def test_voucher_no_override(item, subevent, voucher):
    assert get_price(item, subevent=subevent, voucher=voucher).gross == Decimal('23.00')


@pytest.mark.django_db
def test_voucher_set_price(item, subevent, voucher):
    voucher.price_mode = 'set'
    voucher.value = Decimal('12.00')
    assert get_price(item, subevent=subevent, voucher=voucher).gross == Decimal('12.00')


@pytest.mark.django_db
def test_voucher_subtract(item, subevent, voucher):
    voucher.price_mode = 'subtract'
    voucher.value = Decimal('12.00')
    assert get_price(item, subevent=subevent, voucher=voucher).gross == Decimal('11.00')


@pytest.mark.django_db
def test_voucher_percent(item, subevent, voucher):
    voucher.price_mode = 'percent'
    voucher.value = Decimal('10.00')
    assert get_price(item, subevent=subevent, voucher=voucher).gross == Decimal('20.70')


@pytest.mark.django_db
def test_free_price_ignored_if_disabled(item):
    assert get_price(item, custom_price=Decimal('42.00')).gross == Decimal('23.00')


@pytest.mark.django_db
def test_free_price_ignored_if_lower(item):
    item.free_price = True
    assert get_price(item, custom_price=Decimal('12.00')).gross == Decimal('23.00')


@pytest.mark.django_db
def test_free_price_ignored_if_lower_than_voucher(item, voucher):
    voucher.price_mode = 'set'
    voucher.value = Decimal('50.00')
    assert get_price(item, voucher=voucher, custom_price=Decimal('40.00')).gross == Decimal('50.00')


@pytest.mark.django_db
def test_free_price_ignored_if_lower_than_subevent(item, subevent):
    item.free_price = True
    SubEventItem.objects.create(item=item, subevent=subevent, price=Decimal('50.00'))
    assert get_price(item, subevent=subevent, custom_price=Decimal('40.00')).gross == Decimal('50.00')


@pytest.mark.django_db
def test_free_price_ignored_if_lower_than_variation(item, variation):
    variation.default_price = Decimal('50.00')
    item.free_price = True
    assert get_price(item, variation=variation, custom_price=Decimal('40.00')).gross == Decimal('50.00')


@pytest.mark.django_db
def test_free_price_accepted(item):
    item.free_price = True
    assert get_price(item, custom_price=Decimal('42.00')).gross == Decimal('42.00')


@pytest.mark.django_db
def test_free_price_string(item):
    item.free_price = True
    with translation.override('de'):
        assert get_price(item, custom_price='42,00').gross == Decimal('42.00')


@pytest.mark.django_db
def test_free_price_float(item):
    item.free_price = True
    assert get_price(item, custom_price=42.00).gross == Decimal('42.00')


@pytest.mark.django_db
def test_free_price_limit(item):
    item.free_price = True
    with pytest.raises(ValueError):
        get_price(item, custom_price=Decimal('200000000000'))


@pytest.mark.django_db
def test_free_price_net(item):
    item.free_price = True
    item.tax_rule = item.event.tax_rules.create(rate=Decimal('19.00'))
    assert get_price(item, custom_price=Decimal('100.00'), custom_price_is_net=True).gross == Decimal('119.00')


@pytest.mark.django_db
def test_tax_included(item):
    item.default_price = Decimal('119.00')
    item.tax_rule = item.event.tax_rules.create(rate=Decimal('19.00'), price_includes_tax=True)
    assert get_price(item).gross == Decimal('119.00')
    assert get_price(item).net == Decimal('100.00')
    assert get_price(item).tax == Decimal('19.00')
    assert get_price(item).rate == Decimal('19.00')


@pytest.mark.django_db
def test_tax_none(item):
    item.default_price = Decimal('100.00')
    assert get_price(item).gross == Decimal('100.00')
    assert get_price(item).net == Decimal('100.00')
    assert get_price(item).tax == Decimal('0.00')
    assert get_price(item).rate == Decimal('0.00')


@pytest.mark.django_db
def test_tax_added(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(rate=Decimal('19.00'), price_includes_tax=False)
    assert get_price(item).gross == Decimal('119.00')
    assert get_price(item).net == Decimal('100.00')
    assert get_price(item).tax == Decimal('19.00')
    assert get_price(item).rate == Decimal('19.00')


@pytest.mark.django_db
def test_tax_reverse_charge_valid(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=True, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    assert item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('100.00')


@pytest.mark.django_db
def test_tax_reverse_charge_disabled(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=False, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    assert not item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('119.00')


@pytest.mark.django_db
def test_tax_reverse_charge_no_country(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=True, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
    )
    assert not item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('119.00')


@pytest.mark.django_db
def test_tax_reverse_charge_non_eu_country(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=True, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        country=Country('US')
    )
    assert not item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('100.00')


@pytest.mark.django_db
def test_tax_reverse_charge_same_country(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=True, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('DE')
    )
    assert not item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('119.00')


@pytest.mark.django_db
def test_tax_reverse_charge_consumer(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=True, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        is_business=False, country=Country('BE')
    )
    assert not item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('119.00')


@pytest.mark.django_db
def test_tax_reverse_charge_invalid_vat_id(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        eu_reverse_charge=True, home_country=Country('DE')
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=False,
        country=Country('BE')
    )
    assert not item.tax_rule.is_reverse_charge(ia)
    assert get_price(item, invoice_address=ia).gross == Decimal('119.00')


@pytest.mark.django_db
def test_country_specific_rule_net_based(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        custom_rules=json.dumps([
            {'country': 'BE', 'address_type': '', 'action': 'vat', 'rate': '100.00'}
        ])
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    assert get_price(item, invoice_address=ia).gross == Decimal('200.00')


@pytest.mark.django_db
def test_country_specific_rule_gross_based(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=True,
        custom_rules=json.dumps([
            {'country': 'BE', 'address_type': '', 'action': 'vat', 'rate': '100.00'}
        ])
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    assert get_price(item, invoice_address=ia).gross == Decimal('168.06')


@pytest.mark.django_db
def test_country_specific_rule_net_based_but_keep_gross_if_rate_changes(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False, keep_gross_if_rate_changes=True,
        custom_rules=json.dumps([
            {'country': 'BE', 'address_type': '', 'action': 'vat', 'rate': '100.00'}
        ])
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    p = get_price(item, invoice_address=ia)
    assert p.gross == Decimal('119.00')
    assert p.rate == Decimal('100.00')
    assert p.tax == Decimal('59.50')


@pytest.mark.django_db
def test_country_specific_rule_net_based_subtract_bundled(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False,
        custom_rules=json.dumps([
            {'country': 'BE', 'address_type': '', 'action': 'vat', 'rate': '100.00'}
        ])
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    assert get_price(item, invoice_address=ia, bundled_sum=Decimal('20.00')).gross == (
        round_decimal((Decimal('119.00') - Decimal('20.00')) / Decimal('1.19')) * Decimal('2')
    )


@pytest.mark.django_db
def test_country_specific_rule_gross_based_subtract_bundled(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=True,
        custom_rules=json.dumps([
            {'country': 'BE', 'address_type': '', 'action': 'vat', 'rate': '100.00'}
        ])
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    assert get_price(item, invoice_address=ia, bundled_sum=Decimal('20.00')).gross == (
        round_decimal((Decimal('100.00') - Decimal('20.00')) / Decimal('1.19')) * Decimal('2')
    )


@pytest.mark.django_db
def test_country_specific_rule_net_based_but_keep_gross_if_rate_changes_subtract_bundled(item):
    item.default_price = Decimal('100.00')
    item.tax_rule = item.event.tax_rules.create(
        rate=Decimal('19.00'), price_includes_tax=False, keep_gross_if_rate_changes=True,
        custom_rules=json.dumps([
            {'country': 'BE', 'address_type': '', 'action': 'vat', 'rate': '100.00'}
        ])
    )
    ia = InvoiceAddress(
        is_business=True, vat_id="EU1234", vat_id_validated=True,
        country=Country('BE')
    )
    p = get_price(item, invoice_address=ia, bundled_sum=Decimal('20.00'))
    assert p.gross == Decimal('99.00')
    assert p.rate == Decimal('100.00')
    assert p.tax == Decimal('49.50')