from datetime import timedelta
from decimal import Decimal

from sqlalchemy import select

from factories import make_account, make_category, make_txn, month_back, refresh
from fintracker.db import get_sessionmaker
from fintracker.models import MetricSpendingByCategory


async def rows() -> list[MetricSpendingByCategory]:
    async with get_sessionmaker()() as session:
        return list((await session.execute(select(MetricSpendingByCategory))).scalars().all())


async def test_root_category_rollup_and_uncategorised_row(app):
    card = await make_account(balance="0")
    food = await make_category("Еда")
    groceries = await make_category("Продукты", parent_id=food)
    cafe = await make_category("Кафе", parent_id=food)
    m = month_back(1)
    await make_txn(
        m + timedelta(days=1), outcome="700", outcome_account_id=card, primary_category_id=groceries
    )
    await make_txn(
        m + timedelta(days=2), outcome="300", outcome_account_id=card, primary_category_id=cafe
    )
    await make_txn(m + timedelta(days=3), outcome="150", outcome_account_id=card)
    await refresh()

    by_category = {r.category_id: r for r in await rows()}
    assert by_category[groceries].amount_rub == Decimal("700")
    assert by_category[groceries].root_category_id == food
    assert by_category[cafe].root_category_id == food
    assert by_category[None].amount_rub == Decimal("150")
    assert by_category[None].root_category_id is None
    assert sum(r.amount_rub for r in await rows()) == Decimal("1150")
    assert {r.month for r in await rows()} == {m}


async def test_only_expenses_are_counted(app):
    card = await make_account(balance="0")
    savings = await make_account(name="Вклад", balance="0")
    m = month_back(1)
    await make_txn(m + timedelta(days=1), income="1000", income_account_id=card)
    await make_txn(
        m + timedelta(days=2),
        income="500",
        income_account_id=savings,
        outcome="500",
        outcome_account_id=card,
    )
    await refresh()

    assert await rows() == []


async def test_top_level_category_is_its_own_root(app):
    card = await make_account(balance="0")
    transport = await make_category("Транспорт")
    m = month_back(1)
    await make_txn(
        m + timedelta(days=4),
        outcome="90",
        outcome_account_id=card,
        primary_category_id=transport,
    )
    await refresh()

    (row,) = await rows()
    assert (row.category_id, row.root_category_id) == (transport, transport)