# -----------------------------------------------------------------------------
# Immo-Ka — Agrégateur de maisons à vendre (province de Québec)
# Auteur : Simon-Pierre Boucher — contact@spboucher.ai
# tests/test_mortgage_cmhc.py : assurance prêt hypothécaire (SCHL) — mise de
#   fonds minimale, barème de primes, admissibilité, TVQ sur la prime.
# -----------------------------------------------------------------------------
import unittest

from immoka.mortgage import cmhc


class TestMinDownPayment(unittest.TestCase):
    def test_tiers(self):
        self.assertEqual(cmhc.min_down_payment(400_000), 20_000)   # 5 %
        self.assertEqual(cmhc.min_down_payment(500_000), 25_000)
        self.assertEqual(cmhc.min_down_payment(600_000), 35_000)   # 25k + 10k
        self.assertEqual(cmhc.min_down_payment(1_000_000), 75_000)
        self.assertEqual(cmhc.min_down_payment(1_500_000), 300_000)  # 20 %
        self.assertEqual(cmhc.min_down_payment(2_000_000), 400_000)

    def test_zero(self):
        self.assertEqual(cmhc.min_down_payment(0), 0.0)


class TestPremiumRate(unittest.TestCase):
    def test_bands(self):
        self.assertEqual(cmhc.premium_rate(0.65), 0.0060)
        self.assertEqual(cmhc.premium_rate(0.80), 0.0240)
        self.assertEqual(cmhc.premium_rate(0.90), 0.0310)
        self.assertEqual(cmhc.premium_rate(0.95), 0.0400)
        self.assertIsNone(cmhc.premium_rate(0.96))  # > 95 % : non assurable

    def test_30y_surcharge(self):
        self.assertAlmostEqual(cmhc.premium_rate(0.95, amort_years=30), 0.0420)


class TestInsuranceQuote(unittest.TestCase):
    def test_insured_600k_40k_down(self):
        # prêt 560 k$, RPV 93,3 % → prime 4 % = 22 400 $, TVQ 9,975 %
        q = cmhc.insurance_quote(600_000, 40_000)
        self.assertTrue(q["required"] and q["eligible"])
        self.assertEqual(q["premium"], 22_400)
        self.assertEqual(q["total_mortgage"], 582_400)
        self.assertEqual(q["qc_tax"], round(22_400 * 0.09975, 2))
        self.assertEqual(q["premium_rate"], 4.0)

    def test_uninsured_20_pct_down(self):
        q = cmhc.insurance_quote(500_000, 100_000)
        self.assertFalse(q["required"])
        self.assertEqual(q["premium"], 0.0)
        self.assertEqual(q["total_mortgage"], 400_000)

    def test_over_max_price_not_eligible(self):
        q = cmhc.insurance_quote(1_600_000, 200_000)
        self.assertTrue(q["required"])
        self.assertFalse(q["eligible"])
        self.assertEqual(q["premium"], 0.0)
        self.assertTrue(any("1,5 M$" in i for i in q["issues"]))

    def test_below_min_down_not_eligible(self):
        q = cmhc.insurance_quote(600_000, 20_000)  # min légal = 35 000 $
        self.assertFalse(q["eligible"])
        self.assertTrue(any("minimum légal" in i for i in q["issues"]))

    def test_insured_30y_flagged(self):
        q = cmhc.insurance_quote(400_000, 40_000, amort_years=30)
        self.assertTrue(q["eligible"])
        self.assertTrue(any("premier acheteur" in i for i in q["issues"]))
        # surprime 0,20 % appliquée (RPV 90 % : 3,10 + 0,20 = 3,30 %)
        self.assertEqual(q["premium_rate"], 3.30)

    def test_insured_over_30y_refused(self):
        q = cmhc.insurance_quote(400_000, 40_000, amort_years=35)
        self.assertFalse(q["eligible"])

    def test_invalid_params(self):
        q = cmhc.insurance_quote(0, 0)
        self.assertFalse(q["eligible"])
        self.assertIn("paramètres invalides", q["issues"])


if __name__ == "__main__":
    unittest.main()