"""The aircraft reports its battery twice, with different values.

Observed on the live drone 2026-10-02: `BatteryStateChanged` (0-5-1) arrives as
`00 05 01 00 40` on buffer 126 and `00 05 01 00 00` on buffer 127, repeatedly.
The 64 is corroborated by the drone's own log and tracks a smooth discharge; the
zeros appear in no log line. A store that keeps the newest frame therefore
reported a healthy aircraft as flat, and preflight refused on it.
"""

import pytest

from mcbebop.arsdk.session import Reading
from mcbebop.arsdk.types import Event
from mcbebop.tools.state import _battery

KEY = "BatteryStateChanged_percent"


class FakeSession:
    def __init__(self, entry):
        self.entry = entry

    def state(self, keys):
        return {KEY: self.entry} if self.entry is not None else {}


def test_reading_detects_disagreement():
    assert Reading(0, 1.0, 4, {126: 64, 127: 0}).conflicting
    assert not Reading(64, 1.0, 1, {126: 64}).conflicting
    assert not Reading(64, 1.0, 2, {126: 64, 127: 64}).conflicting


def test_event_carries_its_buffer():
    """Without the source, the store cannot tell two reporters apart."""
    assert Event(ids=(0, 5, 1), name="x", values={}, at=0.0).buffer_id == 0
    assert Event(ids=(0, 5, 1), name="x", values={}, at=0.0, buffer_id=127).buffer_id == 127


def test_the_real_conflict_resolves_to_the_credible_value():
    pct, detail = _battery(FakeSession({"value": 0, "age": 0.1, "sources": {126: 64, 127: 0}}))
    assert pct == 64, "the newest frame said 0; the credible one is 64"
    assert "contested" in detail and "0" in detail, "the caller must learn the number was disputed"


def test_a_lone_reading_is_not_described_as_contested():
    pct, detail = _battery(FakeSession({"value": 64, "age": 0.1, "sources": {126: 64}}))
    assert pct == 64 and detail == "64%"


@pytest.mark.parametrize(
    ("entry", "expected"),
    [
        ({"value": 58, "age": 0.1}, 58),
        ({"value": 0, "age": 0.1, "sources": {126: 0, 127: 0}}, 0),
        (None, None),
    ],
)
def test_other_shapes(entry, expected):
    """A genuine zero from every source still reports zero, and still blocks."""
    assert _battery(FakeSession(entry))[0] == expected