from datetime import date, timedelta, datetime
from odoo.tests.common import TransactionCase, tagged
from odoo.addons.fusion_accounting_bank_rec.services.pattern_extractor import (
    extract_pattern_for_partner,
)


@tagged('post_install', '-at_install')
class TestPatternExtractor(TransactionCase):

    def setUp(self):
        super().setUp()
        self.partner = self.env['res.partner'].create({'name': 'Pattern Test Partner'})
        self.currency = self.env.ref('base.CAD')
        self.company = self.env.company

    def _make_precedent(self, *, amount, days_ago, memo='RBC,ETF', count=1, source='manual'):
        return self.env['fusion.reconcile.precedent'].create({
            'company_id': self.company.id,
            'partner_id': self.partner.id,
            'amount': amount,
            'currency_id': self.currency.id,
            'date': date.today() - timedelta(days=days_ago),
            'memo_tokens': memo,
            'matched_move_line_count': count,
            'reconciled_at': datetime.now() - timedelta(days=days_ago),
            'source': source,
        })

    def test_extracts_typical_amount_range(self):
        for d in [10, 24, 38, 52]:
            self._make_precedent(amount=1847.50, days_ago=d)

        pattern_vals = extract_pattern_for_partner(
            self.env, company_id=self.company.id, partner_id=self.partner.id)
        self.assertIn('typical_amount_range', pattern_vals)
        self.assertEqual(pattern_vals['reconcile_count'], 4)

    def test_detects_exact_amount_strategy(self):
        for d in range(0, 56, 14):
            self._make_precedent(amount=1847.50, days_ago=d, count=1)
        pattern_vals = extract_pattern_for_partner(
            self.env, company_id=self.company.id, partner_id=self.partner.id)
        self.assertEqual(pattern_vals['pref_strategy'], 'exact_amount')

    def test_detects_multi_invoice_strategy(self):
        for d in range(0, 56, 14):
            self._make_precedent(amount=2500.00, days_ago=d, count=3)
        pattern_vals = extract_pattern_for_partner(
            self.env, company_id=self.company.id, partner_id=self.partner.id)
        self.assertEqual(pattern_vals['pref_strategy'], 'multi_invoice')

    def test_computes_cadence_days(self):
        for d in [0, 14, 28, 42]:
            self._make_precedent(amount=1000, days_ago=d)
        pattern_vals = extract_pattern_for_partner(
            self.env, company_id=self.company.id, partner_id=self.partner.id)
        self.assertAlmostEqual(pattern_vals['typical_cadence_days'], 14.0, delta=1)

    def test_extracts_common_memo_tokens(self):
        self._make_precedent(amount=1000, days_ago=10, memo='RBC,ETF,REF')
        self._make_precedent(amount=1000, days_ago=24, memo='RBC,ETF,DEPOSIT')
        self._make_precedent(amount=1000, days_ago=38, memo='RBC,ETF,REF')
        pattern_vals = extract_pattern_for_partner(
            self.env, company_id=self.company.id, partner_id=self.partner.id)
        self.assertIn('RBC', pattern_vals['common_memo_tokens'])
        self.assertIn('ETF', pattern_vals['common_memo_tokens'])

    def test_returns_zero_count_for_partner_with_no_precedents(self):
        other_partner = self.env['res.partner'].create({'name': 'Empty Partner'})
        pattern_vals = extract_pattern_for_partner(
            self.env, company_id=self.company.id, partner_id=other_partner.id)
        self.assertEqual(pattern_vals['reconcile_count'], 0)