import unittest
from datetime import date
from decimal import Decimal
from types import SimpleNamespace

from trytond.modules.account_invoice_do.invoice import Invoice, InvoiceLine


class AccountInvoiceDoUnitTestCase(unittest.TestCase):

    class Currency:
        def round(self, amount):
            return amount.quantize(Decimal('0.01'))

    def _tax_line(
            self, code, amount, template_name=None, rate='0.10'):
        template = (SimpleNamespace(name=template_name)
            if template_name else None)
        tax = SimpleNamespace(
            group=SimpleNamespace(code=code), template=template,
            type='percentage', rate=Decimal(rate), amount=None)
        return SimpleNamespace(tax=tax, amount=Decimal(amount))

    def _line(self, *tax_lines, **values):
        line = SimpleNamespace(
            id=1,
            type='line',
            currency=self.Currency(),
            invoice=None,
            amount=Decimal('100.00'),
            taxes=[tax.tax for tax in tax_lines],
            )
        line._get_taxes = lambda: {
            index: tax for index, tax in enumerate(tax_lines)}
        for name, value in values.items():
            setattr(line, name, value)
        return line

    def test_due_date_uses_last_payment_term_maturity(self):
        term = SimpleNamespace(compute=lambda amount, currency, start: [
                (date(2026, 2, 10), Decimal('40.00')),
                (date(2026, 3, 10), Decimal('60.00')),
                ])
        invoice = SimpleNamespace(
            lines_to_pay=[], payment_term=term, payment_term_date=None,
            invoice_date=date(2026, 1, 10), currency=self.Currency(),
            total_amount=Decimal('100.00'))
        self.assertEqual(
            Invoice._compute_due_date(invoice), date(2026, 3, 10))

    def test_due_date_prefers_posted_maturity_dates(self):
        invoice = SimpleNamespace(lines_to_pay=[
                SimpleNamespace(maturity_date=date(2026, 2, 10)),
                SimpleNamespace(maturity_date=date(2026, 4, 10)),
                ])
        self.assertEqual(
            Invoice._compute_due_date(invoice), date(2026, 4, 10))

    def test_amount_paid_preserves_credit_note_sign(self):
        credit = SimpleNamespace(
            id=1, state='posted', total_amount=Decimal('-118.00'),
            amount_to_pay=Decimal('-18.00'), currency=self.Currency())
        self.assertEqual(
            Invoice.get_amount_paid([credit], 'amount_paid'),
            {1: Decimal('-100.00')})

    def test_days_elapsed_does_not_require_payment_term(self):
        invoice = SimpleNamespace(
            state='posted', invoice_date=date(2026, 1, 1), due_date=None,
            _today=lambda: date(2026, 1, 11))
        invoice._positive_age = lambda reference: Invoice._positive_age(
            invoice, reference)
        self.assertEqual(Invoice.get_days_elapsed(invoice), 10)
        self.assertIsNone(Invoice.get_days_overdue(invoice))

    def test_tax_amounts_use_tryton_computed_tax_lines(self):
        line = self._line(
            self._tax_line('ITBIS', '18.00'),
            self._tax_line('ITBIS', '-5.40', rate='-0.054'),
            self._tax_line('ISC', '10.00'),
            self._tax_line('CDT', '2.00'),
            self._tax_line('ISR', '-10.00'),
            self._tax_line('OTROS', '10.00', 'Legal Tip 10%'))
        self.assertEqual(InvoiceLine._compute_amounts(line), {
                'itbis': Decimal('18.00'),
                'itbis_withholding': Decimal('5.40'),
                'isc': Decimal('10.00'),
                'cdt': Decimal('2.00'),
                'isr_withholding': Decimal('10.00'),
                'tip': Decimal('10.00'),
                'line_total': Decimal('124.60'),
                })

    def test_credit_note_itbis_is_not_classified_as_withholding(self):
        line = self._line(self._tax_line('ITBIS', '-18.00', rate='0.18'))
        self.assertEqual(InvoiceLine._compute_amounts(line), {
                'itbis': Decimal('18.00'),
                'itbis_withholding': Decimal('0.00'),
                'isc': Decimal('0.00'),
                'cdt': Decimal('0.00'),
                'isr_withholding': Decimal('0.00'),
                'tip': Decimal('0.00'),
                'line_total': Decimal('82.00'),
                })

    def test_tax_kind_ignores_incomplete_external_tax_lines(self):
        self.assertIsNone(InvoiceLine._tax_kind(SimpleNamespace(tax=None)))
        tax = SimpleNamespace(
            group=None, template=None, type='percentage',
            rate=Decimal('0.18'), amount=None)
        self.assertIsNone(InvoiceLine._tax_kind(SimpleNamespace(tax=tax)))

    def test_subtotal_resets_after_previous_subtotal(self):
        invoice = SimpleNamespace()
        line1 = self._line()
        subtotal1 = SimpleNamespace(
            id=1, type='subtotal', invoice=invoice, currency=None)
        line2 = self._line(amount=Decimal('50.00'))
        subtotal2 = SimpleNamespace(
            id=2, type='subtotal', invoice=invoice, currency=None)
        invoice.lines = [line1, subtotal1, line2, subtotal2]
        self.assertEqual(
            InvoiceLine._compute_amounts(subtotal2)['line_total'],
            Decimal('50.00'))