"""产品 schema 的金额口径单测（秒级，无外部依赖）。

守：产品 sale_price/stock_quantity 若私写校验不查小数位与容量，5 位小数
会被 Numeric 列静默截断（舍入即算错钱）、超容量会以 500 暴露 —— 校验
口径必须与 schemas/business._check_amount 一致（shipment/receipt 同源）。
"""

import pytest
from pydantic import ValidationError

from app.schemas.product import ProductCreateIn


class TestSalePrice:
    """单价校验：scale=4 对齐 Numeric(14,4) 列。"""

    def test_四位小数通过_回显原样提交(self) -> None:
        """带精度的历史单价必须能原样提交（fba8cfc 教训：编辑被永远拒收）。"""
        body = ProductCreateIn(
            product_name="t_产品",
            product_category="municipal_water",
            sale_price="5000.1234",
        )
        assert body.sale_price == "5000.1234"

    def test_五位小数拒绝而非静默截断(self) -> None:
        with pytest.raises(ValidationError) as exc:
            ProductCreateIn(
                product_name="t_产品",
                product_category="municipal_water",
                sale_price="1.23456",
            )
        assert "最多四位小数" in str(exc.value)

    def test_超容量拒绝(self) -> None:
        """DECIMAL(14,4) 整数部分 10 位：超出即拒绝而非溢出 500。"""
        with pytest.raises(ValidationError):
            ProductCreateIn(
                product_name="t_产品",
                product_category="municipal_water",
                sale_price="99999999999.0000",
            )

    def test_空串归一None_负数拒绝(self) -> None:
        empty = ProductCreateIn(
            product_name="t_产品", product_category="municipal_water", sale_price=""
        )
        assert empty.sale_price is None
        with pytest.raises(ValidationError):
            ProductCreateIn(
                product_name="t_产品", product_category="municipal_water", sale_price="-1"
            )


class TestStockQuantity:
    """数量校验：默认 scale=2 对齐 Numeric(14,2) 列。"""

    def test_三位小数拒绝(self) -> None:
        with pytest.raises(ValidationError):
            ProductCreateIn(
                product_name="t_产品",
                product_category="municipal_water",
                stock_quantity="1.001",
            )

    def test_两位小数通过(self) -> None:
        body = ProductCreateIn(
            product_name="t_产品",
            product_category="municipal_water",
            stock_quantity="1.55",
        )
        assert body.stock_quantity == "1.55"