"""Unit-тесты services/metrics.py — чистая логика, без БД."""
from decimal import Decimal

import pytest

from services.metrics import (
    check_arithmetic,
    normalize_date,
    _to_decimal,
    ClassifyMetrics,
)


class TestNormalizeDate:
    def test_dd_mm_yyyy(self):
        assert normalize_date("01.01.2025") == "2025-01-01"

    def test_already_iso(self):
        assert normalize_date("2025-01-01") == "2025-01-01"

    def test_empty(self):
        assert normalize_date("") is None
        assert normalize_date(None) is None

    def test_unrecognized_passthrough(self):
        assert normalize_date("01 января 2025") == "01 января 2025"


class TestToDecimal:
    def test_int(self):
        assert _to_decimal("50000") == Decimal("50000")

    def test_russian_number(self):
        assert _to_decimal("50 000,00") == Decimal("50000.00")

    def test_nbsp(self):
        assert _to_decimal("1\u00a0000,50") == Decimal("1000.50")

    def test_none(self):
        assert _to_decimal(None) is None
        assert _to_decimal("") is None

    def test_garbage(self):
        assert _to_decimal("не число") is None


class TestCheckArithmetic:
    def test_ok(self):
        ops = [{"action": "ADD", "new_row": {"name": "x", "price": 100, "qty": 2, "sum": 200}}]
        assert check_arithmetic(ops) == []

    def test_mismatch(self):
        ops = [{"action": "ADD", "new_row": {"name": "x", "price": 100, "qty": 2, "sum": 250}}]
        m = check_arithmetic(ops)
        assert len(m) == 1
        assert m[0]["expected_sum"] == 200.0
        assert m[0]["actual_sum"] == 250.0
        assert m[0]["diff"] == 50.0

    def test_update_values(self):
        ops = [{"action": "UPDATE", "new_values": {"price": 10, "qty": 3, "sum": 30}}]
        assert check_arithmetic(ops) == []

    def test_skip_incomplete(self):
        # нет qty → пропуск
        ops = [{"action": "ADD", "new_row": {"name": "x", "price": 100, "sum": 200}}]
        assert check_arithmetic(ops) == []

    def test_skip_non_add_update(self):
        ops = [{"action": "DELETE", "target_hash": "h"}]
        assert check_arithmetic(ops) == []


class TestClassifyMetrics:
    def test_fix_rate(self):
        m = ClassifyMetrics()
        m.record(False)
        m.record(True)
        m.record(False)
        assert m.total == 3
        assert m.fixes == 1
        assert m.fix_rate == pytest.approx(1 / 3)

    def test_empty(self):
        m = ClassifyMetrics()
        assert m.fix_rate == 0.0
        assert m.summary()["total_classifications"] == 0