import json
from datetime import datetime, timezone

import pytest
from coordination_engine.timing import CoordinationFrame, load_frame


def test_one_hour_frame_sets_two_and_three_hour_deadlines():
    frame = CoordinationFrame(3600)
    anchor = datetime(2026, 10, 15, 12, tzinfo=timezone.utc)
    assert frame.deadline(anchor, 2).hour == 14
    assert frame.deadline(anchor, 3).hour == 15


def test_frame_change_rescales_all_multiples():
    assert CoordinationFrame(86400).as_dict() == {
        "frame_seconds": 86400,
        "2f_seconds": 172800,
        "3f_seconds": 259200,
    }
    assert CoordinationFrame(600).as_dict() == {
        "frame_seconds": 600,
        "2f_seconds": 1200,
        "3f_seconds": 1800,
    }


@pytest.mark.parametrize("value", [0, -1, True, 1.5, "3600", None])
def test_invalid_base_frame_is_refused(value):
    with pytest.raises(ValueError):
        CoordinationFrame(value)


def test_naive_deadline_anchor_is_refused():
    with pytest.raises(ValueError, match="timezone"):
        CoordinationFrame(3600).deadline(datetime(2026, 10, 15), 2)


@pytest.mark.parametrize(
    "raw",
    [
        '{"schema_version":"coordination-frame/v1","frame_seconds":3600,"frame_seconds":24}',
        '{"schema_version":"other","frame_seconds":3600}',
        '{"schema_version":"coordination-frame/v1","frame_seconds":3600,"ttl":5}',
        "[]",
        "{}",
    ],
)
def test_invalid_configuration_is_refused_without_fallback(tmp_path, raw):
    path = tmp_path / "frame.json"
    path.write_text(raw)
    with pytest.raises(ValueError):
        load_frame(path)


def test_explicit_config_is_read_without_wall_clock_or_environment_defaults(tmp_path):
    path = tmp_path / "frame.json"
    path.write_text(json.dumps({"schema_version": "coordination-frame/v1", "frame_seconds": 3600}))
    assert load_frame(path).seconds(2) == 7200