"""Unit tests for the Timepix device with a mocked backend."""

from __future__ import annotations

import threading
from types import SimpleNamespace
from unittest import mock

import numpy as np
import ophyd
import pytest
from bec_server.device_server.tests.utils import DMMock
from ophyd import DeviceStatus, StatusBase
from ophyd_devices.tests.utils import MockPV, patch_dual_pvs

from superxas_bec.devices.timepix.timepix import (
    ACQUIRESTATUS,
    DATASOURCE,
    EXPOSUREMODE,
    FILEWRITEMODE,
    TRIGGERMODE,
    TRIGGERSOURCE,
    TDCEdge,
    TDCOuput,
    Timepix,
)
from superxas_bec.devices.timepix.timepix_fly_client.timepix_fly_client import TimePixFlyStatus
from superxas_bec.devices.timepix.timepix_fly_client.timepix_fly_interface import (
    NetAddresses,
    PixelMap,
)

# pylint: disable=protected-access
# pylint: disable=redefined-outer-name


class FakeBackendClient:
    """Backend client double that can finish status callbacks on demand."""

    def __init__(self):
        self.status = TimePixFlyStatus.CONFIG
        self._status_callbacks = {}

    def add_status_callback(self, status, success, error, run=True):
        """Register status callback with optional immediate completion."""
        if run and self.status in success:
            status.set_finished()
            return
        self._status_callbacks[id(status)] = (status, success, error)

    def emit_status(self, status_value: TimePixFlyStatus):
        """Resolve tracked status objects with a simulated backend state."""
        self.status = status_value
        for cb_id, (status, success, error) in list(self._status_callbacks.items()):
            with status._lock:
                if status.done:
                    self._status_callbacks.pop(cb_id, None)
                    continue
                if status_value in success:
                    status.set_finished()
                    self._status_callbacks.pop(cb_id, None)
                elif status_value in error:
                    status.set_exception(RuntimeError(f"backend entered {status_value.value}"))
                    self._status_callbacks.pop(cb_id, None)

    def get_net_addresses(self):
        """Return a deterministic backend raw-data address."""
        return NetAddresses(
            control="127.0.0.1:8452", address="127.0.0.1:8451", server="127.0.0.1:8080"
        )


class FakeBackend:
    """Minimal backend double used to isolate Timepix from backend integration."""

    def __init__(self, *args, **kwargs):
        self.hostname = kwargs.get("hostname") or "localhost"
        self.socket_port = kwargs.get("socket_port", 9876)
        self.timepix_fly_client = FakeBackendClient()
        self.on_connected = mock.Mock()
        self.on_stage = mock.Mock()
        self.on_stop = mock.Mock()
        self.on_destroy = mock.Mock()
        self.add_callback = mock.Mock()
        self._trigger_status = StatusBase()
        self._trigger_status.set_finished()
        self._complete_status = StatusBase()
        self._complete_status.set_finished()

    def on_trigger(self):
        """Return a backend-prepared trigger status."""
        return self._trigger_status

    def on_trigger_finished(self):
        """Return the status that resolves when acquisition is complete."""
        return self._complete_status

    def on_complete(self, status=None):
        """Return a backend completion status."""
        if status is None:
            return self._complete_status
        status.set_finished()
        return status


def _finished_status(device=None):
    """Create a finished status for mocked signal set operations."""
    status = DeviceStatus(device=device)
    status.set_finished()
    return status


def _force_signal_value(signal, value):
    """Set a mocked PV-backed signal value, including read-only EPICS signals."""
    if hasattr(signal, "_read_pv"):
        signal._read_pv.mock_data = value
        return
    signal.put(value)


def _message_value(signal):
    """Extract the signal payload from a BEC message signal."""
    msg = signal.get()
    return msg.signals[signal.name]["value"]


@pytest.fixture(scope="function")
def timepix():
    """Timepix device with mocked EPICS signals and a fully mocked backend."""
    backend = FakeBackend()
    scan_info = SimpleNamespace(
        msg=SimpleNamespace(
            scan_name="step_scan",
            scan_parameters={"exp_time": 0.1, "frames_per_trigger": 2},
            num_points=3,
            scan_id="test",
        )
    )
    with (
        mock.patch.object(ophyd, "cl") as mock_cl,
        mock.patch("superxas_bec.devices.timepix.timepix.TimepixFlyBackend", return_value=backend),
    ):
        mock_cl.get_pv = MockPV
        mock_cl.thread_class = threading.Thread
        dev = Timepix(
            name="timepix",
            prefix="X10DA-ES-TPX1:",
            backend_rest_url="localhost:8452",
            hostname="localhost",
            socket_port=9876,
            scan_info=scan_info,
            device_manager=DMMock(),
        )
        patch_dual_pvs(dev)
        dev.backend = backend
        dev._poll_thread = mock.Mock()
        for walk in dev.walk_signals():
            signal = walk.item
            if hasattr(signal, "set") and hasattr(signal, "put"):
                signal.set = mock.Mock(side_effect=lambda value, _sig=signal, **_kw: (_force_signal_value(_sig, value), _finished_status(_sig))[1])  # type: ignore[method-assign]
        yield dev
        dev._poll_thread_kill_event.set()


@pytest.fixture(scope="function")
def pixel_map():
    """Small valid pixel map used for stage tests."""
    return PixelMap(chips=[[{"i": 0, "p": 0, "f": [1.0]}]])


def test_timepix_on_connected_configures_signals_and_registers_callback(timepix):
    """Connected hook should configure camera, file writer, and backend callback."""
    timepix.on_connected()

    assert timepix.cam.tdc1_enable.get() == 1
    assert timepix.cam.tdc2_enable.get() == 1
    assert timepix.cam.raw_enable.get() == 1
    assert timepix.cam.tdc1_edge.get() == TDCEdge.RISING
    assert timepix.cam.tdc1_output.get() == TDCOuput.ALL_CHANNELS
    assert timepix.cam.trigger_mode.get() == TRIGGERMODE.INTERNAL
    assert timepix.cam.trigger_source.get() == TRIGGERSOURCE.HDMI1_1
    assert timepix.cam.exposure_mode.get() == EXPOSUREMODE.TIMED
    assert timepix.cam.array_counter.get() == 0
    assert timepix.hdf.enable.get() == "1"
    assert timepix.hdf.file_write_mode.get() == FILEWRITEMODE.STREAM.value
    assert timepix.hdf.auto_save.get() == 1
    assert timepix.cam.array_callbacks.get() == 1
    timepix.backend.add_callback.assert_called_once_with(timepix.msg_buffer_callback)
    timepix._poll_thread.start.assert_called_once()


def test_timepix_on_stage_configures_camera_writer_and_mocked_backend(timepix, pixel_map):
    """Stage should configure camera settings and forward config to the backend."""
    timepix._pixel_map = pixel_map

    with (
        mock.patch(
            "superxas_bec.devices.timepix.timepix.get_full_path",
            return_value="/tmp/timepix/test_scan.h5",
        ),
    ):
        _force_signal_value(timepix.hdf.enable, "Enable")
        timepix.on_stage()

    assert timepix.cam.acquire_time.get() == pytest.approx(0.1 - timepix._readout_time)
    assert timepix.cam.acquire_period.get() == pytest.approx(0.1)
    assert timepix.cam.num_images.get() == 2
    assert timepix.cam.data_source.get() == DATASOURCE.IMAGE
    assert timepix.hdf.file_path.get() == "/tmp/timepix"
    assert timepix.hdf.file_name.get() == "test_scan.h5"
    assert timepix.hdf.num_capture.get() == 6
    assert timepix.hdf.capture.get() == 1
    assert timepix.cam.raw_file_template.get() == ""
    assert timepix.cam.raw_file_path.get() == "tcp://connect@127.0.0.1:8451"
    assert timepix.backend.on_stage.call_count == 1
    other_config = timepix.backend.on_stage.call_args.kwargs["other_config"]
    assert (
        other_config.output_uri
        == "redis://localhost:0000/public/timepix_fly_backend/raw_data?scan-id=test"
    )
    assert other_config.TRoiStep == timepix.troistep
    assert other_config.TRoiN == timepix.troin
    assert timepix.backend.on_stage.call_args.kwargs["pixel_map"] == pixel_map
    file_event = timepix.file_event.get()
    assert file_event.file_path == "/tmp/timepix/test_scan.h5"
    assert file_event.done is False
    assert file_event.successful is False


def test_timepix_on_stage_configures_mocked_backend(timepix, pixel_map):
    """Stage should configure camera settings and forward config to the backend."""
    timepix._pixel_map = pixel_map

    with (
        mock.patch(
            "superxas_bec.devices.timepix.timepix.get_full_path",
            return_value="/tmp/timepix/test_scan.h5",
        ),
    ):
        _force_signal_value(timepix.hdf.enable, "Disable")
        # File event should not be emitted when hdf.enable is "Disable"
        with mock.patch.object(timepix.file_event, "put") as mock_file_event_put:
            timepix.hdf.capture.put(0)
            timepix.on_stage()
            mock_file_event_put.assert_not_called()

    assert timepix.hdf.capture.get() == 0
    assert timepix.cam.acquire_time.get() == pytest.approx(0.1 - timepix._readout_time)
    assert timepix.cam.acquire_period.get() == pytest.approx(0.1)
    assert timepix.cam.num_images.get() == 2
    assert timepix.cam.data_source.get() == DATASOURCE.IMAGE
    assert timepix.cam.raw_file_template.get() == ""
    assert timepix.cam.raw_file_path.get() == "tcp://connect@127.0.0.1:8451"
    assert timepix.backend.on_stage.call_count == 1
    other_config = timepix.backend.on_stage.call_args.kwargs["other_config"]
    assert (
        other_config.output_uri
        == "redis://localhost:0000/public/timepix_fly_backend/raw_data?scan-id=test"
    )
    assert other_config.TRoiStep == timepix.troistep
    assert other_config.TRoiN == timepix.troin
    assert timepix.backend.on_stage.call_args.kwargs["pixel_map"] == pixel_map


def test_timepix_on_stage_without_xes_skips_backend_configuration(timepix):
    """When XES is disabled, the backend-specific stage call should be skipped."""
    timepix.enable_xes = False

    with mock.patch(
        "superxas_bec.devices.timepix.timepix.get_full_path",
        return_value="/tmp/timepix/no_xes_scan.h5",
    ):
        timepix.on_stage()

    timepix.backend.on_stage.assert_not_called()


def test_timepix_on_trigger_combines_camera_and_backend_status(timepix):
    """Trigger should arm the backend first and then drive the camera."""
    backend_done = StatusBase()
    backend_done.set_finished()
    backend_finished = StatusBase()
    timepix.backend._trigger_status = backend_done
    timepix.backend._complete_status = backend_finished

    status = timepix.on_trigger()

    assert isinstance(status, StatusBase)
    assert timepix.cam.acquire.get() == 1
    _force_signal_value(timepix.cam.acquire_busy, ACQUIRESTATUS.ACQUIRING)
    _force_signal_value(timepix.cam.acquire_busy, ACQUIRESTATUS.DONE)
    backend_finished.set_finished()
    status.wait(timeout=0.1)
    assert status.done is True
    assert status.success is True


def test_timepix_on_complete(timepix):
    """Complete should wait for writer/backend completion and emit a success file event."""

    # I. Case I. With hdf.enable "Enable", should wait for both writer and camera to be done before emitting file event
    timepix.hdf.enable.put("Enable")
    timepix._full_path = "/tmp/timepix/final_scan.h5"
    timepix._n_images = 3
    _force_signal_value(timepix.cam.acquire_busy, ACQUIRESTATUS.ACQUIRING)
    timepix.hdf.capture.put(ACQUIRESTATUS.ACQUIRING)
    timepix.hdf.write_file.put(ACQUIRESTATUS.ACQUIRING)

    status = timepix.on_complete()

    _force_signal_value(timepix.cam.acquire_busy, ACQUIRESTATUS.DONE)
    timepix.hdf.capture.put(ACQUIRESTATUS.DONE)
    timepix.hdf.write_file.put(ACQUIRESTATUS.DONE)
    timepix.hdf.write_status.put(0)
    _force_signal_value(timepix.hdf.num_captured, 3)
    status.wait(timeout=1)

    file_event = timepix.file_event.get()
    assert file_event.file_path == "/tmp/timepix/final_scan.h5"
    assert file_event.done is True
    assert file_event.successful is True

    # II. Case II. With hdf.enable "Disable", should not wait for writer and only wait for camera to be done before emitting file event
    timepix.hdf.enable.put("Disable")
    timepix._n_images = 3
    _force_signal_value(timepix.cam.acquire_busy, ACQUIRESTATUS.ACQUIRING)
    timepix.hdf.capture.put(ACQUIRESTATUS.ACQUIRING)
    timepix.hdf.write_file.put(ACQUIRESTATUS.ACQUIRING)
    with mock.patch.object(timepix.file_event, "put") as mock_file_event_put:
        status = timepix.on_complete()
        _force_signal_value(timepix.cam.acquire_busy, ACQUIRESTATUS.DONE)
        status.wait(timeout=1)
        mock_file_event_put.assert_not_called()
        assert status.done is True
        assert status.success is True


def test_timepix_msg_buffer_callback_updates_xes_signals(timepix):
    """The backend message callback should populate all exported XES data signals."""
    start_frame = {
        "type": "StartFrame",
        "Mode": "TOA",
        "TRoiStart": 0,
        "TRoiStep": 1,
        "TRoiN": 2,
        "NumEnergyPoints": 8,
        "save_interval": 1,
    }
    data_frames = [
        {
            "type": "XesData",
            "period": 131000,
            "totalEvents": 36,
            "TDSpectra": list(range(16)),
            "beforeROI": 0,
            "afterROI": 0,
        }
    ]
    end_frame = {"type": "EndFrame", "error": "", "periods": 4}
    timepix.troin = 2

    timepix.msg_buffer_callback(start_frame, data_frames, end_frame)

    expected_xes = np.array(
        [[0, 1, 2, 3, 4, 5, 6, 7], [8, 9, 10, 11, 12, 13, 14, 15]], dtype=np.float32
    )
    np.testing.assert_array_equal(_message_value(timepix.xes_data), expected_xes)
    np.testing.assert_array_equal(
        _message_value(timepix.xes_spectra), np.array([28, 92], dtype=np.float32)
    )
    np.testing.assert_array_equal(
        _message_value(timepix.xes_energy_1), np.array([6, 38], dtype=np.float32)
    )
    np.testing.assert_array_equal(
        _message_value(timepix.xes_energy_2), np.array([22, 54], dtype=np.float32)
    )
    assert _message_value(timepix.total_periods) == pytest.approx(4 / 131000)
    np.testing.assert_array_equal(_message_value(timepix.tds_period), np.array([1.0]))
    assert _message_value(timepix.total_events) == 36


def test_timepix_on_stop_stops_camera_writer_and_backend(timepix):
    """Stop should stop camera acquisition and delegate backend stop."""
    timepix.cam.acquire.put(1)
    timepix.hdf.capture.put(1)

    timepix.on_stop()

    assert timepix.cam.acquire.get() == 0
    assert timepix.hdf.capture.get() == 0
    timepix.backend.on_stop.assert_called_once()


def test_timepix_on_destroy_cleans_up_backend(timepix):
    """Destroy should stop polling and forward cleanup to the backend."""
    timepix.on_destroy()

    assert timepix._poll_thread_kill_event.is_set() is True
    timepix.backend.on_stop.assert_called_once()
    timepix.backend.on_destroy.assert_called_once()


def test_timepix_on_prescan_returns_correct_status(timepix):
    """Prescan should return a finished status if the backend is ready."""
    # Case I. With hdf.enable "Enable", should wait for both writer and camera to be ready
    timepix.hdf.enable._read_pv.mock_data = "Enable"
    timepix.cam.acquire_busy._read_pv.mock_data = ACQUIRESTATUS.ACQUIRING
    timepix.hdf.capture._read_pv.mock_data = ACQUIRESTATUS.DONE
    # Should be combined status of writer and control
    status = timepix.on_pre_scan()
    assert status.done is False
    timepix.cam.acquire_busy._read_pv.mock_data = ACQUIRESTATUS.DONE
    assert status.done is False
    timepix.hdf.capture._read_pv.mock_data = ACQUIRESTATUS.ACQUIRING
    status.wait(timeout=1)
    assert status.done is True
    assert status.success is True

    # Case II. With hdf.enable "Enable", should wait for both writer and camera to be ready
    timepix.hdf.enable._read_pv.mock_data = "Disable"
    timepix.cam.acquire_busy._read_pv.mock_data = ACQUIRESTATUS.ACQUIRING
    status = timepix.on_pre_scan()
    assert status.done is False
    timepix.cam.acquire_busy._read_pv.mock_data = ACQUIRESTATUS.DONE
    status.wait(timeout=1)
    assert status.done is True
    assert status.success is True