from types import SimpleNamespace

import pytest

from app.analytics import analyse, enrich, running_cost


def run(grade=0):
    return SimpleNamespace(
        sport="running",
        distance_m=600,
        samples=[
            {
                "distance": i * 3,
                "time": i,
                "elevation": 100 + i * 3 * grade,
                "speed": 3,
                "heart_rate": 150,
                "cadence": 170,
            }
            for i in range(201)
        ],
        laps=[{"distance": 301}, {"distance": 299}],
    )


def test_flat_gap_and_laps_use_distance_weighted_time():
    result = analyse(run())
    assert result["summary"]["gap"] == pytest.approx(1000 / 3)
    assert result["summary"]["gap_coverage"] == 100
    assert [lap["gap"] for lap in result["laps"]] == pytest.approx([1000 / 3] * 2)
    assert sum(lap["gap_time"] for lap in result["laps"]) == pytest.approx(200)
    assert result["terrain"][1]["heart_rate"] == 150


@pytest.mark.parametrize("grade", [-0.1, 0.1])
def test_slope_adjusts_pace_using_cost_ratio(grade):
    activity = run(grade)
    row = enrich(activity.samples)[100]
    assert row["grade"] == pytest.approx(grade * 100)
    assert row["gap"] == pytest.approx(1000 / 3 * 3.6 / running_cost(grade))
    gap = analyse(activity)["summary"]["gap"]
    assert (gap < 1000 / 3) if grade > 0 else (gap > 1000 / 3)


def test_missing_data_and_nonrunning_do_not_invent_gap():
    activity = run()
    for row in activity.samples:
        row["elevation"] = None
    assert analyse(activity)["summary"]["gap"] is None
    activity = run()
    activity.sport = "cycling"
    assert analyse(activity)["summary"]["gap"] is None
    activity = run()
    for row in activity.samples:
        row["time"] = None
    assert analyse(activity)["summary"]["gap"] is None


def test_recording_gap_excluded_from_time_and_distance():
    activity = run()
    for row in activity.samples[100:]:
        row["time"] += 100
    result = analyse(activity)
    assert result["summary"]["gap"] == pytest.approx(1000 / 3)
    assert result["summary"]["gap_coverage"] == pytest.approx(99.5)


def test_extreme_slopes_and_stationary_records_have_no_gap():
    assert analyse(run(0.5))["summary"]["gap"] is None
    activity = run()
    for row in activity.samples:
        row["distance"] = 0
    assert analyse(activity)["summary"]["gap"] is None