from datetime import UTC, date, datetime
from decimal import Decimal
from pathlib import Path

import pytest

from broker_sync.fx import FxCache
from broker_sync.models import AccountType, Activity, ActivityType, FxRateSource
from broker_sync.normaliser import normalise_to_gbp


def _buy_usd(amount_usd: Decimal = Decimal("100")) -> Activity:
    return Activity(
        external_id="schwab:1",
        account_id="schwab-rsu",
        account_type=AccountType.GIA,
        date=datetime(2026, 4, 1, tzinfo=UTC),
        activity_type=ActivityType.BUY,
        symbol="META",
        quantity=Decimal("1"),
        unit_price=amount_usd,
        currency="USD",
        fee=Decimal("0"),
    )


def test_gbp_activity_unchanged(tmp_path: Path) -> None:
    cache = FxCache(tmp_path / "fx.db")
    a = Activity(
        external_id="t212:1",
        account_id="t212-isa",
        account_type=AccountType.ISA,
        date=datetime(2026, 4, 1, tzinfo=UTC),
        activity_type=ActivityType.BUY,
        symbol="VUAG",
        quantity=Decimal("1"),
        unit_price=Decimal("100"),
        currency="GBP",
    )
    out = normalise_to_gbp(a, cache=cache)
    assert out.amount_gbp == Decimal("100")
    assert out.fx_rate_gbp == Decimal("1")
    assert out.fx_rate_source is FxRateSource.ECB_LIVE


def test_usd_buy_converts_using_cache(tmp_path: Path) -> None:
    cache = FxCache(tmp_path / "fx.db")
    cache.put("USD", date(2026, 4, 1), Decimal("0.80"), FxRateSource.ECB_LIVE)
    out = normalise_to_gbp(_buy_usd(Decimal("100")), cache=cache)
    assert out.amount_gbp == Decimal("80.00")
    assert out.fx_rate_gbp == Decimal("0.80")
    assert out.fx_rate_source is FxRateSource.ECB_LIVE


def test_dividend_amount_drives_gbp(tmp_path: Path) -> None:
    cache = FxCache(tmp_path / "fx.db")
    cache.put("USD", date(2026, 4, 1), Decimal("0.80"), FxRateSource.ECB_LIVE)
    div = Activity(
        external_id="schwab:div:1",
        account_id="schwab-rsu",
        account_type=AccountType.GIA,
        date=datetime(2026, 4, 1, tzinfo=UTC),
        activity_type=ActivityType.DIVIDEND,
        currency="USD",
        amount=Decimal("50"),
    )
    out = normalise_to_gbp(div, cache=cache)
    assert out.amount_gbp == Decimal("40.00")


def test_missing_rate_raises(tmp_path: Path) -> None:
    cache = FxCache(tmp_path / "fx.db")
    with pytest.raises(LookupError):
        normalise_to_gbp(_buy_usd(), cache=cache)