from lintunes.tap_tempo import TapTempo


def test_steady_taps_120_bpm():
    tempo = TapTempo()
    bpm = None
    for i in range(5):
        bpm = tempo.tap(10.0 + i * 0.5)  # 0.5s intervals = 120 bpm
    assert bpm == 120


def test_first_tap_gives_no_bpm():
    tempo = TapTempo()
    assert tempo.tap(1.0) is None
    assert tempo.tap_count == 1


def test_long_gap_resets_series():
    tempo = TapTempo()
    tempo.tap(0.0)
    tempo.tap(0.5)
    assert tempo.bpm() == 120
    # 5 seconds later: new series, old taps discarded
    assert tempo.tap(5.5) is None
    assert tempo.tap_count == 1
    assert tempo.tap(6.1) == 100  # 0.6s interval


def test_long_session_converges_exactly():
    tempo = TapTempo()
    bpm = None
    for i in range(30):
        bpm = tempo.tap(i * 0.5)  # 30 steady taps at 120 bpm
    assert bpm == 120


def test_whole_session_is_averaged():
    tempo = TapTempo()
    # One sloppy 1.0s interval up front, then 20 taps at 0.5s. All 21 taps
    # count (no rolling window), so the estimate is the overall average
    # 10.5s / 20 intervals = 0.525s -> 114 bpm, not the recent-taps 120.
    tempo.tap(0.0)
    t = 1.0
    bpm = None
    for _ in range(20):
        bpm = tempo.tap(t)
        t += 0.5
    assert tempo.tap_count == 21
    assert bpm == 114


def test_reset():
    tempo = TapTempo()
    tempo.tap(0.0)
    tempo.tap(0.5)
    tempo.reset()
    assert tempo.bpm() is None
    assert tempo.tap_count == 0