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_window_uses_recent_taps_only():
    tempo = TapTempo()
    # 4 slow taps (1s = 60bpm) then 8 fast taps (0.25s = 240bpm);
    # only the last 8 taps count, so the slow ones age out entirely
    t = 0.0
    for _ in range(4):
        tempo.tap(t)
        t += 1.0
    for _ in range(8):
        tempo.tap(t)
        t += 0.25
    assert tempo.bpm() == 240


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