import dataclasses

import pytest

from exporter.models import (
    DeviceMetricsSnapshot,
    INT32_MAX,
    TransceiverChannelRecord,
    TransceiverRecord,
    is_invalid_value,
)


def test_transceiver_record_is_frozen():
    record = TransceiverRecord(
        device="dev1",
        component_name="comp1",
        logical_port="1/0/1",
        present="PRESENT",
        oper_status="ACTIVE",
        temperature_c=40.0,
        supply_voltage_v=3.3,
        vendor="H3C",
        serial="SN1",
        part_number="PN",
        hardware_rev="1.0",
    )
    with pytest.raises(dataclasses.FrozenInstanceError):
        record.device = "dev2"


def test_transceiver_channel_record_is_frozen():
    channel = TransceiverChannelRecord(
        device="dev1",
        component_name="comp1",
        logical_port="1/0/1",
        channel_index=0,
        logical_channel="1/0/1:1",
        rx_power_dbm=-3.0,
        tx_power_dbm=-1.0,
        bias_current_ma=10.0,
        laser_temperature_c=25.0,
    )
    with pytest.raises(dataclasses.FrozenInstanceError):
        channel.channel_index = 1


def test_snapshot_is_frozen():
    tx = TransceiverRecord(device="d", component_name="c", logical_port="p")
    snap = DeviceMetricsSnapshot(device="d", collected_at=0.0, transceivers=(tx,), channels=())
    with pytest.raises(dataclasses.FrozenInstanceError):
        snap.device = "other"


@pytest.mark.parametrize(
    "value, expected",
    [
        (float(INT32_MAX), True),
        (INT32_MAX, True),
        (INT32_MAX - 1, False),
        (-INT32_MAX, False),
        (None, False),
    ],
)
def test_is_invalid_value_exact_int32_max(value, expected):
    assert is_invalid_value(value) is expected