from modjam import payload


def test_make_payload_pads_to_size():
    text, token = payload.make_test_payload(size=80, seq=1, elapsed=0.5, ts=1234.5)
    assert len(text) == 80
    assert text.startswith("1234.5,0.5,1,")
    assert f",{token}|" in text


def test_make_payload_short_when_prefix_exceeds_size():
    text, token = payload.make_test_payload(size=5, seq=99, elapsed=12.34, ts=1234567890.0)
    # prefix already > 5; payload returns prefix as-is
    assert text.endswith("|")
    assert token in text


def test_token_is_hex_and_correct_length():
    _, token = payload.make_test_payload(size=80, seq=1, elapsed=0.0, ts=0.0)
    assert len(token) == payload.TOKEN_LEN
    assert all(c in "0123456789abcdef" for c in token)


def test_tokens_are_unique():
    tokens = {payload.make_test_payload(80, 1, 0, 0)[1] for _ in range(50)}
    assert len(tokens) == 50  # vanishingly unlikely to collide


def test_extract_token_roundtrip():
    text, token = payload.make_test_payload(size=120, seq=42, elapsed=3.0, ts=999.0)
    assert payload.extract_token(text) == token


def test_extract_token_returns_none_on_protocol_message():
    assert payload.extract_token("1234567890|A|IDLE|-100") is None
    assert payload.extract_token("START|name:foo") is None
    assert payload.extract_token("STOP") is None


def test_extract_token_returns_none_on_legacy_format():
    # 3-field legacy format (no token) — should not falsely extract
    assert payload.extract_token("1234.5,1.0,42|abcdef") is None


def test_extract_token_rejects_non_hex():
    assert payload.extract_token("1234.5,1.0,42,nothex!!|abc") is None


def test_extract_token_handles_empty():
    assert payload.extract_token("") is None
    assert payload.extract_token("nopipe") is None