from copy import deepcopy

import pytest

from railiance_clock import attribution
from railiance_clock.client import Clock, FileTrust
from railiance_clock.core import ClockError


def test_disabled_attribution_does_not_construct_clock(monkeypatch):
    monkeypatch.delenv('TEST_CLOCK_TRUST', raising=False)
    def unexpected(_):
        pytest.fail('unconfigured attribution constructed a clock')
    monkeypatch.setattr(attribution, '_clock', unexpected)
    assert attribution.from_environment('TEST_CLOCK_TRUST') == {}


def test_recording_evidence_preserves_original_event(setup, monkeypatch):
    path, _, timer, transport = setup
    clock = Clock(FileTrust(path), timer=timer, transport=transport)
    monkeypatch.setenv('TEST_CLOCK_TRUST', str(path))
    monkeypatch.setattr(attribution, '_clock', lambda _: clock)
    event = {'event_id': 'old-event', 'timestamp': '1999-01-01T10:00:00+01:00',
             'clock_domain': 'old-boot', 'sequence': 7, 'predecessors': ['earlier']}
    original = deepcopy(event)
    evidence = attribution.from_environment('TEST_CLOCK_TRUST')
    enriched = {**event, **evidence}
    assert event == original
    assert all(enriched[k] == v for k, v in original.items())
    assert set(evidence) == {'railiance_time'}
    sample = evidence['railiance_time']
    assert sample['kind'] == 'recording_time' and sample['status'] == 'usable'
    assert sample['lower_ns'] <= sample['upper_ns']
    assert sample['sample_id'] and sample['authority_id'] == 'railiance01'
    assert 'occurrence_time' not in sample
    # A wall-clock label is retained as provenance, not recalibrated by this API.
    assert enriched['timestamp'] == original['timestamp']


@pytest.mark.parametrize('error', [OSError('secret-path'), ClockError('private reason'),
                                  KeyError('private field'), TypeError('private type')])
def test_unavailable_attribution_is_sanitized(monkeypatch, error):
    monkeypatch.setenv('TEST_CLOCK_TRUST', '/unused')
    def unavailable(_):
        raise error
    monkeypatch.setattr(attribution, '_clock', unavailable)
    assert attribution.from_environment('TEST_CLOCK_TRUST') == {
        'railiance_time': {'status': 'unavailable', 'kind': 'recording_time'}}


def test_expired_cached_clock_never_returns_old_evidence(setup, monkeypatch):
    path, _, timer, transport = setup
    clock = Clock(FileTrust(path), timer=timer, transport=transport)
    monkeypatch.setenv('TEST_CLOCK_TRUST', str(path))
    monkeypatch.setattr(attribution, '_clock', lambda _: clock)
    assert attribution.from_environment('TEST_CLOCK_TRUST')['railiance_time']['status'] == 'usable'
    timer.n = 61_000_000_000
    assert attribution.from_environment('TEST_CLOCK_TRUST') == {
        'railiance_time': {'status': 'unavailable', 'kind': 'recording_time'}}