from app.telemetry import detect_wire_spike, parse_proc_net_dev

PROC_NET_DEV = """Inter-|   Receive                                                |  Transmit
 face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed
    lo: 1234567    1000    0    0    0     0          0         0  1234567    1000    0    0    0     0       0          0
  eth0: 9876543    5000    0    0    0     0          0         0  1111111    4000    0    0    0     0       0          0
"""


def test_parse_proc_net_dev_extracts_counters():
    counters = parse_proc_net_dev(PROC_NET_DEV)
    assert counters == {
        "lo": (1234567, 1234567),
        "eth0": (9876543, 1111111),
    }


def test_parse_proc_net_dev_ignores_malformed_lines():
    assert parse_proc_net_dev("garbage\nno colon here\n") == {}


def test_spike_needs_history():
    assert detect_wire_spike([], 1_000_000) is None
    assert detect_wire_spike([10_000.0] * 3, 1_000_000) is None


def test_spike_fires_on_real_surge():
    history = [20_000.0, 25_000.0, 22_000.0, 21_000.0, 23_000.0, 24_000.0, 22_500.0]
    ratio = detect_wire_spike(history, 400_000.0)
    assert ratio is not None
    assert ratio > 10


def test_spike_ignores_normal_fluctuation():
    history = [20_000.0, 25_000.0, 22_000.0, 21_000.0, 23_000.0, 24_000.0, 22_500.0]
    assert detect_wire_spike(history, 30_000.0) is None


def test_spike_has_absolute_floor_for_silent_links():
    # A nearly idle link jittering by a few KB/s must never cry ghost.
    history = [100.0, 150.0, 120.0, 90.0, 110.0, 130.0, 140.0]
    assert detect_wire_spike(history, 5_000.0) is None


def test_spike_adapts_to_loud_baseline():
    # Once the line is genuinely busy, the same surge is no longer anomalous.
    history = [350_000.0, 380_000.0, 360_000.0, 370_000.0, 355_000.0, 375_000.0, 365_000.0]
    assert detect_wire_spike(history, 400_000.0) is None