import json
from datetime import date, timedelta
from decimal import Decimal

import pytest
from django.core.serializers.json import DjangoJSONEncoder
from django.db import DatabaseError, transaction
from django.utils.timezone import now
from django_countries.fields import Country
from django_scopes import scope, scopes_disabled

from pretix.base.models import (
    Event, Invoice, InvoiceAddress, Item, ItemVariation, Order, OrderPosition,
    Organizer,
)
from pretix.base.models.orders import OrderFee
from pretix.base.services.invoices import (
    build_preview_invoice_pdf, generate_cancellation, generate_invoice,
    invoice_pdf_task, invoice_qualified, regenerate_invoice,
)
from pretix.base.services.orders import OrderChangeManager
from pretix.base.settings import GlobalSettingsObject


@pytest.fixture
def env():
    o = Organizer.objects.create(name='Dummy', slug='dummy')
    with scope(organizer=o):
        event = Event.objects.create(
            organizer=o, name='Dummy', slug='dummy',
            date_from=now(), plugins='pretix.plugins.banktransfer'
        )
        o = Order.objects.create(
            code='FOO', event=event, email='dummy@dummy.test',
            status=Order.STATUS_PENDING,
            datetime=now(), expires=now() + timedelta(days=10),
            total=0, locale='en'
        )
        tr = event.tax_rules.create(rate=Decimal('19.00'))
        o.fees.create(fee_type=OrderFee.FEE_TYPE_PAYMENT, value=Decimal('0.25'), tax_rate=Decimal('19.00'),
                      tax_value=Decimal('0.05'), tax_rule=tr)
        ticket = Item.objects.create(event=event, name='Early-bird ticket',
                                     category=None, default_price=23, tax_rule=tr,
                                     admission=True)
        t_shirt = Item.objects.create(event=event, name='T-Shirt',
                                      category=None, default_price=42, tax_rule=tr,
                                      admission=True)
        variation = ItemVariation.objects.create(value='M', item=t_shirt)
        OrderPosition.objects.create(
            order=o,
            item=ticket,
            variation=None,
            price=Decimal("23.00"),
            positionid=1,
        )
        OrderPosition.objects.create(
            order=o,
            item=t_shirt,
            variation=variation,
            price=Decimal("42.00"),
            positionid=2,
        )
        OrderPosition.objects.create(
            order=o,
            item=t_shirt,
            variation=variation,
            price=Decimal("42.00"),
            positionid=3,
            canceled=True
        )
        gs = GlobalSettingsObject()
        gs.settings.ecb_rates_date = date.today()
        gs.settings.ecb_rates_dict = json.dumps({
            "USD": "1.1648",
            "RON": "4.5638",
            "CZK": "26.024",
            "BGN": "1.9558",
            "HRK": "7.4098",
            "EUR": "1.0000",
            "NOK": "9.3525",
            "HUF": "305.15",
            "DKK": "7.4361",
            "PLN": "4.2408",
            "GBP": "0.89350",
            "SEK": "9.5883"
        }, cls=DjangoJSONEncoder)
        yield event, o


@pytest.mark.django_db
def test_locale_setting(env):
    event, order = env
    event.settings.set('invoice_language', 'de')
    with scopes_disabled():
        inv = generate_invoice(order)
    assert inv.locale == 'de'


@pytest.mark.django_db
def test_locale_user(env):
    event, order = env
    order.locale = 'en'
    event.settings.set('invoice_language', '__user__')
    inv = generate_invoice(order)
    assert inv.locale == order.locale


@pytest.mark.django_db
def test_address_old_country(env):
    event, order = env
    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street',
                                  zipcode='12345', city='London', country_old='England', country='',
                                  order=order)
    inv = generate_invoice(order)
    assert inv.invoice_to == "Acme Company\n221B Baker Street\n12345 London\nEngland"


@pytest.mark.django_db
def test_address_with_state(env):
    event, order = env
    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street',
                                  zipcode='46530', city='Granger', country=Country('US'), state='IN',
                                  order=order)
    inv = generate_invoice(order)
    assert inv.invoice_to == "Acme Company\n221B Baker Street\n46530 Granger IN\nUnited States of America"


@pytest.mark.django_db
def test_address_with_state_long(env):
    event, order = env
    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street',
                                  zipcode='46530', city='Granger', country=Country('MY'), state='10',
                                  order=order)
    inv = generate_invoice(order)
    assert inv.invoice_to == "Acme Company\n221B Baker Street\n46530 Granger Selangor\nMalaysia"


@pytest.mark.django_db
def test_address(env):
    event, order = env
    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street',
                                  zipcode='12345', city='London', country=Country('GB'),
                                  order=order)
    inv = generate_invoice(order)
    assert inv.invoice_to == "Acme Company\n221B Baker Street\n12345 London\nUnited Kingdom"


@pytest.mark.django_db
def test_address_vat_id(env):
    event, order = env
    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street',
                                  name_parts={'full_name': 'Sherlock Holmes', '_scheme': 'full'},
                                  zipcode='12345',
                                  city='London',
                                  country_old='UK',
                                  country='', vat_id='UK1234567', order=order)
    inv = generate_invoice(order)
    assert inv.invoice_to == "Acme Company\nSherlock Holmes\n221B Baker Street\n12345 London\nUK\nVAT-ID: UK1234567"


@pytest.mark.django_db
def test_positions_skip_free(env):
    event, order = env
    event.settings.invoice_include_free = False
    op1 = order.positions.first()
    op1.price = Decimal('0.00')
    op1.save()
    inv = generate_invoice(order)
    assert inv.lines.count() == 2


@pytest.mark.django_db
def test_reverse_charge_note(env):
    event, order = env

    tr = event.tax_rules.first()
    tr.eu_reverse_charge = True
    tr.home_country = Country('DE')
    tr.save()

    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street', zipcode='12345', city='Warsaw',
                                  country=Country('PL'), vat_id='PL123456780', vat_id_validated=True, order=order,
                                  is_business=True)

    ocm = OrderChangeManager(order, None)
    ocm.recalculate_taxes()
    ocm.commit()
    assert not order.positions.filter(tax_value__gt=0).exists()

    inv = generate_invoice(order)
    assert "reverse charge" in inv.additional_text.lower()
    assert inv.foreign_currency_display == "PLN"
    assert inv.foreign_currency_rate == Decimal("4.2408")
    assert inv.foreign_currency_rate_date == date.today()


@pytest.mark.django_db
def test_reverse_charge_foreign_currency_data_too_old(env):
    event, order = env
    gs = GlobalSettingsObject()
    gs.settings.ecb_rates_date = date.today() - timedelta(days=14)

    tr = event.tax_rules.first()
    tr.eu_reverse_charge = True
    tr.home_country = Country('DE')
    tr.save()

    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street', zipcode='12345', city='Warsaw',
                                  country=Country('PL'), vat_id='PL123456780', vat_id_validated=True, order=order,
                                  is_business=True)

    ocm = OrderChangeManager(order, None)
    ocm.recalculate_taxes()
    ocm.commit()
    assert not order.positions.filter(tax_value__gt=0).exists()

    inv = generate_invoice(order)
    assert "reverse charge" in inv.additional_text.lower()
    assert inv.foreign_currency_rate is None
    assert inv.foreign_currency_rate_date is None


@pytest.mark.django_db
def test_reverse_charge_foreign_currency_disabvled(env):
    event, order = env
    event.settings.invoice_eu_currencies = False

    tr = event.tax_rules.first()
    tr.eu_reverse_charge = True
    tr.home_country = Country('DE')
    tr.save()

    event.settings.set('invoice_language', 'en')
    InvoiceAddress.objects.create(company='Acme Company', street='221B Baker Street', zipcode='12345', city='Warsaw',
                                  country=Country('PL'), vat_id='PL123456780', vat_id_validated=True, order=order,
                                  is_business=True)

    ocm = OrderChangeManager(order, None)
    ocm.recalculate_taxes()
    ocm.commit()
    assert not order.positions.filter(tax_value__gt=0).exists()

    inv = generate_invoice(order)
    assert "reverse charge" in inv.additional_text.lower()
    assert inv.foreign_currency_rate is None
    assert inv.foreign_currency_rate_date is None


@pytest.mark.django_db
def test_positions(env):
    event, order = env
    inv = generate_invoice(order)
    assert inv.lines.count() == 3
    first = inv.lines.first()
    assert 'Early-bird' in first.description
    assert first.gross_value == Decimal('23.00')

    second = inv.lines.all()[1]
    assert 'T-Shirt' in second.description
    assert 'M' in second.description
    assert second.gross_value == Decimal('42.00')

    last = inv.lines.last()
    assert 'Payment' in last.description
    fee = order.fees.get(fee_type=OrderFee.FEE_TYPE_PAYMENT)
    assert last.gross_value == fee.value
    assert last.tax_rate == fee.tax_rate
    assert last.tax_value == fee.tax_value
    assert inv.invoice_to == ""


@pytest.mark.django_db
def test_rebuilding(env):
    event, order = env
    inv = generate_invoice(order)
    inv2 = regenerate_invoice(inv)
    assert inv.order == inv2.order

    inv3 = generate_cancellation(inv)
    inv4 = regenerate_invoice(inv3)
    assert inv3.order == inv4.order


@pytest.mark.django_db
def test_cannot_delete_invoice(env):
    event, order = env
    inv = generate_invoice(order)
    with pytest.raises(Exception):
        inv.delete()


@pytest.mark.django_db
def test_cannot_write_invoice_without_order(env):
    event, _ = env
    with pytest.raises(Exception):
        i = Invoice(order=None, event=event)
        i.save()


@pytest.mark.django_db
def test_pdf_generation(env):
    event, order = env
    inv = generate_invoice(order)
    cancellation = generate_cancellation(inv)
    assert invoice_pdf_task(inv.pk)
    assert invoice_pdf_task(cancellation.pk)


@pytest.mark.django_db
def test_pdf_generation_custom_text(env):
    event, order = env
    event.settings.set('invoice_introductory_text', 'introductory invoice text')
    # set a really long additional text, to make the invoice span two pages
    event.settings.set('invoice_additional_text', 'additional invoice text\n' * 100)
    event.settings.set('show_date_to', False)
    inv = generate_invoice(order)
    assert invoice_pdf_task(inv.pk)


@pytest.mark.django_db
def test_pdf_preview_generation(env):
    event, order = env
    assert build_preview_invoice_pdf(event)


@pytest.mark.django_db
def test_invoice_numbers(env):
    event, order = env
    order2 = Order.objects.create(
        code='BAR', event=event, email='dummy2@dummy.test',
        status=Order.STATUS_PENDING,
        datetime=now(), expires=now() + timedelta(days=10),
        total=0,
        locale='en'
    )
    order2.fees.create(fee_type=OrderFee.FEE_TYPE_PAYMENT, value=Decimal('0.25'), tax_rate=Decimal('0.00'),
                       tax_value=Decimal('0.00'))
    testorder = Order.objects.create(
        code='BAR', event=event, email='dummy2@dummy.test',
        status=Order.STATUS_PENDING,
        datetime=now(), expires=now() + timedelta(days=10),
        total=0, testmode=True,
        locale='en'
    )
    inv1 = generate_invoice(order)
    inv2 = generate_invoice(order)
    invt1 = generate_invoice(testorder)

    event.settings.set('invoice_numbers_consecutive', False)
    inv3 = generate_invoice(order)
    inv4 = generate_invoice(order)
    inv21 = generate_invoice(order2)
    invt2 = generate_invoice(testorder)
    inv22 = generate_invoice(order2)

    event.settings.set('invoice_numbers_consecutive', True)
    inv5 = generate_invoice(order)
    inv6 = generate_invoice(order)
    invt3 = generate_invoice(testorder)
    inv7 = generate_invoice(order)
    Invoice.objects.filter(pk=inv6.pk).delete()  # This should never ever happen, but what if it happens anyway?
    inv8 = generate_invoice(order)
    inv23 = generate_invoice(order2)

    event.settings.set('invoice_numbers_counter_length', 6)
    inv24 = generate_invoice(order)
    event.settings.set('invoice_numbers_counter_length', 1)
    inv25 = generate_invoice(order)
    inv26 = generate_invoice(order)

    # expected behaviour for switching between numbering formats or dealing with gaps
    assert inv1.invoice_no == '00001'
    assert inv2.invoice_no == '00002'
    assert inv3.invoice_no == '{}-3'.format(order.code)
    assert inv4.invoice_no == '{}-4'.format(order.code)
    assert inv5.invoice_no == '00003'
    assert inv6.invoice_no == '00004'
    assert inv7.invoice_no == '00005'
    assert inv8.invoice_no == '00006'

    # test that separate orders are counted separately in this mode
    assert inv21.invoice_no == '{}-1'.format(order2.code)
    assert inv22.invoice_no == '{}-2'.format(order2.code)
    # but consecutively in this mode
    assert inv23.invoice_no == '00007'
    assert inv24.invoice_no == '000008'
    assert inv25.invoice_no == '9'
    assert inv26.invoice_no == '10'

    # test Invoice.number, too
    assert inv1.number == '{}-00001'.format(event.slug.upper())
    assert inv3.number == '{}-{}-3'.format(event.slug.upper(), order.code)

    assert invt1.number == '{}-TEST-00001'.format(event.slug.upper())
    assert invt2.number == '{}-TEST-{}-2'.format(event.slug.upper(), testorder.code)
    assert invt3.number == '{}-TEST-00002'.format(event.slug.upper())


@pytest.mark.django_db
def test_invoice_number_prefixes(env):
    event, order = env
    event2 = Event.objects.create(
        organizer=event.organizer, name='Dummy', slug='dummy2',
        date_from=now(), plugins='pretix.plugins.banktransfer'
    )
    order2 = Order.objects.create(
        event=event2, email='dummy2@dummy.test',
        status=Order.STATUS_PENDING,
        datetime=now(), expires=now() + timedelta(days=10),
        total=0,
        locale='en'
    )
    order2.fees.create(fee_type=OrderFee.FEE_TYPE_PAYMENT, value=Decimal('0.25'), tax_rate=Decimal('0.00'),
                       tax_value=Decimal('0.00'))
    event.settings.set('invoice_numbers_consecutive', False)
    event2.settings.set('invoice_numbers_consecutive', False)
    assert generate_invoice(order).number == 'DUMMY-{}-1'.format(order.code)
    assert generate_invoice(order2).number == 'DUMMY2-{}-1'.format(order2.code)

    event.settings.set('invoice_numbers_consecutive', True)
    event2.settings.set('invoice_numbers_consecutive', True)
    event.settings.set('invoice_numbers_prefix', '')
    event2.settings.set('invoice_numbers_prefix', '')

    assert generate_invoice(order).number == 'DUMMY-00001'
    assert generate_invoice(order).number == 'DUMMY-00002'
    assert generate_invoice(order2).number == 'DUMMY2-00001'
    assert generate_invoice(order2).number == 'DUMMY2-00002'

    event.settings.set('invoice_numbers_prefix', 'shared_')
    event2.settings.set('invoice_numbers_prefix', 'shared_')

    assert generate_invoice(order).number == 'shared_00001'
    assert generate_invoice(order2).number == 'shared_00002'
    assert generate_invoice(order).number == 'shared_00003'
    assert generate_invoice(order2).number == 'shared_00004'

    event.settings.set('invoice_numbers_consecutive', False)
    event2.settings.set('invoice_numbers_consecutive', False)
    assert generate_invoice(order).number == 'shared_{}-6'.format(order.code)
    assert generate_invoice(order2).number == 'shared_{}-6'.format(order2.code)

    event2.settings.set('invoice_numbers_prefix', 'inv_')
    event2.settings.set('invoice_numbers_prefix_cancellations', 'crd_')
    event2.settings.set('invoice_numbers_consecutive', True)
    event2.settings.set('invoice_numbers_counter_length', 4)
    i = generate_invoice(order2)
    assert i.number == 'inv_0001'
    assert generate_cancellation(i).number == 'crd_0001'

    event2.settings.set('invoice_numbers_prefix', 'inv_%Y%m%d_')
    i = generate_invoice(order2)
    assert i.number == 'inv_%s_0001' % now().date().strftime('%Y%m%d')

    # Test database uniqueness check
    with pytest.raises(DatabaseError):
        with transaction.atomic():
            Invoice.objects.create(
                order=order,
                event=order.event,
                organizer=order.event.organizer,
                date=now().date(),
                locale='en',
                invoice_no='00001',
            )


@pytest.mark.django_db
def test_sales_channels_qualify(env):
    event, order = env
    event.settings.set('invoice_generate', 'admin')

    # Orders with Total of 0 do never qualify
    assert invoice_qualified(order) is False

    order.total = Decimal('42.00')

    # Order with default Sales Channel (web)
    assert invoice_qualified(order) is True

    event.settings.set('invoice_generate_sales_channels', [])
    assert invoice_qualified(order) is False