"""Audit log hash-chain helper tests (pure function, no DB)."""

from __future__ import annotations

from datetime import UTC, datetime
from uuid import uuid4

from mimic.audit.log import audit_hash


def test_hash_changes_with_metadata() -> None:
    ts = datetime(2026, 5, 21, 12, 0, tzinfo=UTC)
    actor = uuid4()
    base = {
        "prev_hash": None,
        "ts": ts,
        "actor_id": actor,
        "action": "ttp.create",
        "resource_type": "ttp",
        "resource_id": "t-1",
        "metadata": {"name": "whoami"},
    }
    h1 = audit_hash(**base)
    h2 = audit_hash(**{**base, "metadata": {"name": "whoami2"}})
    assert h1 != h2
    assert len(h1) == 64
    assert all(c in "0123456789abcdef" for c in h1)


def test_hash_changes_with_prev_hash() -> None:
    ts = datetime(2026, 5, 21, 12, 0, tzinfo=UTC)
    h_no_prev = audit_hash(
        prev_hash=None,
        ts=ts,
        actor_id=None,
        action="x",
        resource_type="r",
        resource_id="1",
        metadata={},
    )
    h_with_prev = audit_hash(
        prev_hash="abc",
        ts=ts,
        actor_id=None,
        action="x",
        resource_type="r",
        resource_id="1",
        metadata={},
    )
    assert h_no_prev != h_with_prev


def test_hash_stable_for_same_input() -> None:
    ts = datetime(2026, 5, 21, 12, 0, tzinfo=UTC)
    base = {
        "prev_hash": "aa",
        "ts": ts,
        "actor_id": None,
        "action": "x",
        "resource_type": "r",
        "resource_id": "1",
        "metadata": {"k": "v"},
    }
    assert audit_hash(**base) == audit_hash(**base)