"""AZ-394 — Msp2InavAdapter outbound AC tests."""

from __future__ import annotations

import logging
import threading
from typing import Any
from unittest import mock
from uuid import UUID, uuid4

import numpy as np
import pytest

from gps_denied_onboard._types.fc import FcKind, PortConfig
from gps_denied_onboard._types.geo import LatLonAlt
from gps_denied_onboard._types.state import (
    EstimatorOutput,
    PoseSourceLabel,
    Quat,
)
from gps_denied_onboard.components.c8_fc_adapter._covariance_projector import (
    CovarianceProjector,
)
from gps_denied_onboard.components.c8_fc_adapter._msp2_sensor_gps_encoder import (
    MSP2_SENSOR_GPS_CODE,
    decode_msp2_sensor_gps,
)
from gps_denied_onboard.components.c8_fc_adapter.errors import (
    FcAdapterConfigError,
    FcEmitError,
    SourceSetSwitchNotSupportedError,
)
from gps_denied_onboard.components.c8_fc_adapter.msp2_inav_adapter import (
    Msp2InavAdapter,
)
from gps_denied_onboard.config import load_config

# ----------------------------------------------------------------------
# Helpers — MSP / secondary-MAVLink stand-ins


class _MspStub:
    def __init__(self) -> None:
        self.raw_msgs: list[tuple[int, bytes]] = []
        self.closed = False

    def send_RAW_msg(self, code: int, data: bytes) -> None:
        self.raw_msgs.append((int(code), bytes(data)))

    def close(self) -> None:
        self.closed = True


class _SecondaryMavStub:
    def __init__(self) -> None:
        self.statustext_calls: list[tuple[int, bytes]] = []
        self.closed = False
        # Mirror pymavlink connection.mav shape.
        self.mav = self
        # Track signing-key state per RESTRICT-COMM-2 (Invariant 9):
        # the unit-test adapter MUST never call setup_signing on us.
        self.setup_signing_calls: list[Any] = []

    def statustext_send(self, severity: int, text: bytes) -> None:
        self.statustext_calls.append((int(severity), bytes(text)))

    def setup_signing(self, key: Any) -> None:
        self.setup_signing_calls.append(key)

    def close(self) -> None:
        self.closed = True


@pytest.fixture
def msp() -> _MspStub:
    return _MspStub()


@pytest.fixture
def secondary() -> _SecondaryMavStub:
    return _SecondaryMavStub()


def _inav_config(tmp_path) -> Any:
    env = {
        "FC_ADAPTER": "inav",
        "FC_PORT_DEVICE": "/dev/null",
        "FC_PORT_BAUD": "115200",
        "FC_SIGNING_KEY_SOURCE": "none",
    }
    return load_config(env=env, paths=(), require_env=False)


def _make_output(
    *,
    source_label: PoseSourceLabel = PoseSourceLabel.VISUAL_PROPAGATED,
    smoothed: bool = False,
    cov: np.ndarray | None = None,
    wgs: LatLonAlt | None = None,
    frame_id: UUID | int | None = None,
) -> EstimatorOutput:
    if cov is None:
        cov = np.eye(6, dtype=np.float64) * 0.25
    if wgs is None:
        wgs = LatLonAlt(lat_deg=50.0, lon_deg=30.0, alt_m=100.0)
    if frame_id is None:
        frame_id = uuid4()
    elif isinstance(frame_id, int):
        frame_id = UUID(int=frame_id)
    return EstimatorOutput(
        frame_id=frame_id,
        position_wgs84=wgs,
        orientation_world_T_body=Quat(w=1.0, x=0.0, y=0.0, z=0.0),
        velocity_world_mps=(0.0, 0.0, 0.0),
        covariance_6x6=cov,
        source_label=source_label,
        last_satellite_anchor_age_ms=0,
        smoothed=smoothed,
        emitted_at=0,
    )


@pytest.fixture
def adapter(msp: _MspStub, secondary: _SecondaryMavStub, tmp_path) -> Msp2InavAdapter:
    cfg = _inav_config(tmp_path)
    fdr = mock.MagicMock()
    a = Msp2InavAdapter(
        config=cfg,
        wgs_converter=mock.MagicMock(),
        covariance_projector=CovarianceProjector(fdr_client=fdr),
        fdr_client=fdr,
        msp_connect_factory=lambda device, baud: msp,
        secondary_mavlink_factory=lambda: secondary,
    )
    port = PortConfig(fc_kind=FcKind.INAV, device="/dev/null", baud=115200)
    a.open(port, signing_key=None)
    yield a
    a.close()


# ----------------------------------------------------------------------
# AC-1: field fidelity


def test_ac1_msp2_field_fidelity(adapter: Msp2InavAdapter, msp: _MspStub) -> None:
    # Arrange
    cov = np.diag([0.25, 0.25, 9.0, 1.0, 1.0, 1.0]).astype(np.float64)
    wgs = LatLonAlt(lat_deg=50.4501, lon_deg=30.5234, alt_m=180.0)
    output = _make_output(cov=cov, wgs=wgs)
    expected_mm = CovarianceProjector(fdr_client=mock.MagicMock()).to_inav_h_pos_accuracy_mm(output)

    # Act
    result = adapter.emit_external_position(output)

    # Assert
    assert len(msp.raw_msgs) == 1
    code, payload = msp.raw_msgs[0]
    assert code == MSP2_SENSOR_GPS_CODE
    decoded = decode_msp2_sensor_gps(payload)
    assert decoded.fix_type == 3
    assert decoded.latitude_e7 == int(wgs.lat_deg * 1e7)
    assert decoded.longitude_e7 == int(wgs.lon_deg * 1e7)
    assert decoded.msl_altitude_cm == int(wgs.alt_m * 100.0)
    assert decoded.h_pos_accuracy_mm == expected_mm
    assert result.fc_kind is FcKind.INAV
    assert result.horiz_accuracy_m == pytest.approx(expected_mm / 1000.0)


# ----------------------------------------------------------------------
# AC-2: every frame, monotonic seq


def test_ac2_msp2_every_frame_with_seq(adapter: Msp2InavAdapter, msp: _MspStub) -> None:
    seqs = []
    for i in range(100):
        result = adapter.emit_external_position(_make_output(frame_id=i))
        seqs.append(result.sequence_number)
    assert len(msp.raw_msgs) == 100
    # AC-2: monotonically incrementing (modulo uint8 wrap)
    assert seqs[0] == 1
    assert seqs[-1] == 100 & 0xFF


# ----------------------------------------------------------------------
# AC-3: STATUSTEXT on secondary channel only, on transitions


def test_ac3_statustext_secondary_only_on_transitions(
    adapter: Msp2InavAdapter, msp: _MspStub, secondary: _SecondaryMavStub
) -> None:
    adapter._provenance._min_interval_s = 0.0  # type: ignore[attr-defined]
    labels = [PoseSourceLabel.VISUAL_PROPAGATED, PoseSourceLabel.SATELLITE_ANCHORED]
    for i in range(100):
        label = labels[(i // 10) % 2]
        adapter.emit_external_position(_make_output(source_label=label, frame_id=i))
    # 10 transitions including the initial None->visual_propagated
    assert len(secondary.statustext_calls) == 10
    # AC-3: NEVER on primary MSP2 channel
    for code, _ in msp.raw_msgs:
        assert code == MSP2_SENSOR_GPS_CODE


# ----------------------------------------------------------------------
# AC-4: signing-key rejection


def test_ac4_signing_key_rejected(msp: _MspStub, secondary: _SecondaryMavStub, tmp_path) -> None:
    cfg = _inav_config(tmp_path)
    fdr = mock.MagicMock()
    a = Msp2InavAdapter(
        config=cfg,
        wgs_converter=mock.MagicMock(),
        covariance_projector=CovarianceProjector(fdr_client=fdr),
        fdr_client=fdr,
        msp_connect_factory=lambda device, baud: msp,
        secondary_mavlink_factory=lambda: secondary,
    )
    port = PortConfig(fc_kind=FcKind.INAV, device="/dev/null", baud=115200)
    with pytest.raises(FcAdapterConfigError, match="iNav does not support MAVLink signing"):
        a.open(port, signing_key=b"\x00" * 32)


# ----------------------------------------------------------------------
# AC-5: signing-asymmetry — adapter never calls setup_signing on secondary


def test_ac5_signing_asymmetry_no_signed_flag(
    adapter: Msp2InavAdapter, secondary: _SecondaryMavStub
) -> None:
    for i in range(50):
        adapter.emit_external_position(_make_output(frame_id=i))
    assert secondary.setup_signing_calls == []


# ----------------------------------------------------------------------
# AC-6: source-set-switch unsupported


def test_ac6_source_set_switch_unsupported(adapter: Msp2InavAdapter) -> None:
    with pytest.raises(SourceSetSwitchNotSupportedError, match="iNav"):
        adapter.request_source_set_switch()


# ----------------------------------------------------------------------
# AC-7: smoothed rejected


def test_ac7_smoothed_rejected(adapter: Msp2InavAdapter, msp: _MspStub) -> None:
    with pytest.raises(FcEmitError, match="smoothed"):
        adapter.emit_external_position(_make_output(smoothed=True))
    assert msp.raw_msgs == []


# ----------------------------------------------------------------------
# AC-8: non-SPD cov rejected


def test_ac8_non_spd_covariance_rejected(adapter: Msp2InavAdapter, msp: _MspStub) -> None:
    bad = np.eye(6, dtype=np.float64)
    bad[0, 0] = -1.0
    with pytest.raises(FcEmitError):
        adapter.emit_external_position(_make_output(cov=bad))
    assert msp.raw_msgs == []


# ----------------------------------------------------------------------
# AC-9: single-writer thread


def test_ac9_single_writer_thread(adapter: Msp2InavAdapter) -> None:
    adapter.emit_external_position(_make_output())
    err: list[BaseException] = []

    def run() -> None:
        try:
            adapter.emit_external_position(_make_output(frame_id=2))
        except RuntimeError as e:
            err.append(e)

    t = threading.Thread(target=run)
    t.start()
    t.join(timeout=2.0)
    assert len(err) == 1
    assert "single-writer" in str(err[0]).lower()


# ----------------------------------------------------------------------
# AC-10: first emit logged once


def test_ac10_first_emit_logged_once(
    adapter: Msp2InavAdapter, caplog: pytest.LogCaptureFixture
) -> None:
    with caplog.at_level(logging.INFO):
        for i in range(5):
            adapter.emit_external_position(_make_output(frame_id=i))
    first = [rec for rec in caplog.records if getattr(rec, "kind", None) == "c8.inav.first_emit"]
    assert len(first) == 1


# ----------------------------------------------------------------------
# Invariant 2 cross-check: iNav config rejects ephemeral signing


def test_inav_config_rejects_signing(tmp_path) -> None:
    env = {
        "FC_ADAPTER": "inav",
        "FC_SIGNING_KEY_SOURCE": "ephemeral_per_flight",
    }
    with pytest.raises(Exception, match="adapter='inav'"):
        load_config(env=env, paths=(), require_env=False)