from decimal import Decimal

import pytest

from grid_trading.domain.grid_levels import generate_grid_levels


def test_generate_grid_levels_compounds_percentage_spacing_and_rounds_values():
    levels = generate_grid_levels(
        current_price=Decimal("10.00"),
        spacing=Decimal("0.03"),
        amount_per_grid=Decimal("10000"),
        lot_size=100,
        levels=3,
    )

    assert [item.level for item in levels] == [1, 2, 3]
    assert [item.buy_price for item in levels] == [Decimal("9.70"), Decimal("9.41"), Decimal("9.13")]
    assert [item.buy_amount for item in levels] == [Decimal("10000.00")] * 3
    assert [item.suggested_quantity for item in levels] == [1000, 1000, 1000]
    assert [item.actual_investment for item in levels] == [
        Decimal("9700.00"),
        Decimal("9410.00"),
        Decimal("9130.00"),
    ]
    assert [item.sell_price for item in levels] == [Decimal("9.99"), Decimal("9.69"), Decimal("9.40")]
    assert [item.estimated_gross_profit for item in levels] == [
        Decimal("290.00"),
        Decimal("280.00"),
        Decimal("270.00"),
    ]


def test_generate_grid_levels_uses_zero_quantity_when_amount_cannot_buy_one_lot():
    [level] = generate_grid_levels(
        current_price=Decimal("10.00"),
        spacing=Decimal("0.03"),
        amount_per_grid=Decimal("500"),
        lot_size=100,
        levels=1,
    )

    assert level.buy_price == Decimal("9.70")
    assert level.suggested_quantity == 0
    assert level.actual_investment == Decimal("0.00")
    assert level.estimated_gross_profit == Decimal("0.00")


@pytest.mark.parametrize(
    ("current_price", "spacing", "amount_per_grid", "lot_size", "levels"),
    [
        (Decimal("0"), Decimal("0.03"), Decimal("10000"), 100, 10),
        (Decimal("10"), Decimal("0"), Decimal("10000"), 100, 10),
        (Decimal("10"), Decimal("1"), Decimal("10000"), 100, 10),
        (Decimal("10"), Decimal("0.03"), Decimal("0"), 100, 10),
        (Decimal("10"), Decimal("0.03"), Decimal("10000"), 0, 10),
        (Decimal("10"), Decimal("0.03"), Decimal("10000"), 100, 0),
        (Decimal("10"), Decimal("0.03"), Decimal("10000"), 100, 101),
    ],
)
def test_generate_grid_levels_validates_inputs(current_price, spacing, amount_per_grid, lot_size, levels):
    with pytest.raises(ValueError):
        generate_grid_levels(
            current_price=current_price,
            spacing=spacing,
            amount_per_grid=amount_per_grid,
            lot_size=lot_size,
            levels=levels,
        )