from datetime import UTC, datetime, timedelta
from uuid import uuid4

from app.geo import GeoLocation
from app.schemas import AccessAttempted
from app.scoring import HeuristicScorer, risk_band


def _evt(
    *,
    guest_id=None,
    fingerprint=None,
    ip=None,
    user_agent="Mozilla/5.0",
    occurred_at=None,
):
    return AccessAttempted(
        event_id=uuid4(),
        guest_id=guest_id or uuid4(),
        token_id=uuid4(),
        access_log_id=uuid4(),
        fingerprint=fingerprint,
        ip_address=ip,
        user_agent=user_agent,
        occurred_at=occurred_at or datetime.now(UTC),
    )


def test_first_access_with_full_signals_is_low_risk():
    scorer = HeuristicScorer()
    evt = _evt(
        fingerprint={"ua": "Chrome", "platform": "macOS"},
        ip="203.0.113.7",
    )
    res = scorer.score(evt)
    assert res.score <= 30
    assert risk_band(res.score) == "low"


def test_fingerprint_change_drives_score_up():
    scorer = HeuristicScorer()
    guest = uuid4()
    first = _evt(guest_id=guest, fingerprint={"ua": "Chrome"}, ip="203.0.113.7")
    scorer.score(first)

    second = _evt(guest_id=guest, fingerprint={"ua": "Safari"}, ip="203.0.113.7")
    res = scorer.score(second)

    assert res.score >= 40
    assert any("fingerprint" in r for r in res.reasons)


def test_ip_change_and_fingerprint_change_classify_high_or_block():
    scorer = HeuristicScorer()
    guest = uuid4()
    scorer.score(_evt(guest_id=guest, fingerprint={"ua": "Chrome"}, ip="203.0.113.7"))

    suspicious = _evt(
        guest_id=guest,
        fingerprint={"ua": "Curl/8"},
        ip="198.51.100.42",
        user_agent=None,
    )
    res = scorer.score(suspicious)

    assert res.score >= 60
    assert risk_band(res.score) in {"high", "block"}


def test_missing_fingerprint_and_user_agent_flagged():
    scorer = HeuristicScorer()
    res = scorer.score(_evt(fingerprint=None, ip="203.0.113.1", user_agent=None))
    assert "no device fingerprint provided" in res.reasons
    assert "missing user agent" in res.reasons


def test_score_clamped_to_0_100():
    scorer = HeuristicScorer()
    # 10 successive accesses with no fingerprint, no UA, changing IPs
    guest = uuid4()
    for i in range(12):
        res = scorer.score(_evt(guest_id=guest, fingerprint=None, ip=f"10.0.{i}.1", user_agent=None))
        assert 0 <= res.score <= 100


# --- Tier 2 Block G: geo_jump ---


_LAGOS = GeoLocation(country="NG", city="Lagos", lat=6.5244, lon=3.3792)
_PARIS = GeoLocation(country="FR", city="Paris", lat=48.8566, lon=2.3522)


def test_geo_jump_fires_on_implausible_travel():
    """Two accesses 5,000+ km apart within 12 minutes is the textbook
    forwarded-link case the spec targets."""
    scorer = HeuristicScorer()
    guest = uuid4()
    t0 = datetime.now(UTC)

    first = _evt(
        guest_id=guest,
        fingerprint={"ua": "Chrome"},
        ip="102.89.0.1",
        occurred_at=t0,
    )
    scorer.score(first, geo=_LAGOS)

    twelve_mins_later = _evt(
        guest_id=guest,
        fingerprint={"ua": "Chrome"},
        ip="80.10.20.30",
        occurred_at=t0 + timedelta(minutes=12),
    )
    res = scorer.score(twelve_mins_later, geo=_PARIS)

    assert any("Lagos" in r and "Paris" in r for r in res.reasons), res.reasons
    # geo_jump (100 × 0.40) + ip_change (80 × 0.20) = 56 weighted; the
    # single-signal cap (geo_jump + ip_change both ≥ 70, so 2 signals)
    # does NOT trigger and the score stays > the cap-at-55 floor.
    assert res.score >= 55, res.score


def test_geo_jump_does_not_fire_for_local_movement():
    """A train-trip distance shouldn't escalate."""
    scorer = HeuristicScorer()
    guest = uuid4()
    t0 = datetime.now(UTC)
    london = GeoLocation(country="GB", city="London", lat=51.5074, lon=-0.1278)
    brighton = GeoLocation(country="GB", city="Brighton", lat=50.8225, lon=-0.1372)

    scorer.score(
        _evt(guest_id=guest, fingerprint={"ua": "Chrome"}, ip="80.0.0.1", occurred_at=t0),
        geo=london,
    )
    res = scorer.score(
        _evt(
            guest_id=guest,
            fingerprint={"ua": "Chrome"},
            ip="80.0.0.1",
            occurred_at=t0 + timedelta(hours=2),
        ),
        geo=brighton,
    )
    assert not any("Lagos" in r or "minutes" in r.lower() for r in res.reasons)


def test_geo_jump_carries_geo_back_on_result():
    scorer = HeuristicScorer()
    res = scorer.score(_evt(fingerprint={"ua": "Chrome"}, ip="102.89.0.1"), geo=_LAGOS)
    assert res.geo is _LAGOS