from datetime import UTC, datetime
from uuid import uuid4

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",
):
    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=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