from data_layer.food_attributes import (
    create_extension_attribute,
    macros_and_attributes_to_values,
    normalize_attr_key,
    normalize_attr_unit,
    scale_to_per_100g,
)


def test_scale_serving_to_per_100g():
    assert scale_to_per_100g(1.1, 8) == 1.1 * (100 / 8)
    assert scale_to_per_100g(10, 100) == 10
    assert scale_to_per_100g(10, None) == 10


def test_attr_key_and_unit_normalize():
    assert normalize_attr_key("Vitamin D3") == "VITAMIN_D3"
    assert normalize_attr_unit("ug") == "µg"
    assert normalize_attr_unit("mcg") == "µg"


def test_create_extension_returns_existing():
    class _Cur:
        def __init__(self):
            self.calls = 0

        def execute(self, sql, params=None):
            self.calls += 1
            self._row = {"id": 1, "attr_key": "VITAMIN_D3", "name_de": "Vitamin D3", "name_en": None, "unit": "µg", "category": "extension", "origin": "extension"} if self.calls == 1 else None

        def fetchone(self):
            return self._row

    row = create_extension_attribute(_Cur(), "Vitamin D3", "µg")
    assert row["attr_key"] == "VITAMIN_D3"


def test_norsan_label_epa_converts():
    """Etikett: 1100 mg EPA = 1.1 g in 8 g Portion → g/100 g."""
    vals = macros_and_attributes_to_values(
        {"kcal": 72, "protein_g": 0, "fat_g": 8, "carbs_g": 0},
        {"EPA": 1.1},
        serving_g=8,
    )
    assert abs(vals["FAT"] - 100) < 0.01
    assert abs(vals["EPA"] - 13.75) < 0.01
    assert abs(vals["ENERCC"] - 900) < 0.01