"""
motion_capture/plugin.py

LabUI Motion Capture plugin.

When enabled, adds a "Camera" device type to the Add Device dialog.
Each camera added by the user becomes a first-class device in the
acquisition pipeline — data flows through the standard
Device → Signal → Channel → Plot stream.

Custom filter registered globally:
    pixel_to_mm — convert pixel coords to mm using a px_per_mm value.
    Add it in Signals → Channels on x_pos or y_pos.

Install OpenCV for real camera support:
    pip install opencv-python
"""

from __future__ import annotations

from typing import List, Optional

from plugins.base_plugin import LabPlugin, PluginAction, PluginContext


class MotionCapturePlugin(LabPlugin):

    # ── Metadata ──────────────────────────────────────────────────────────

    @property
    def plugin_id(self) -> str: return "motion_capture"

    @property
    def name(self) -> str: return "Motion Capture"

    @property
    def version(self) -> str: return "1.0.0"

    @property
    def description(self) -> str:
        return (
            "Adds a Camera device type to the Add Device dialog. "
            "Stream x/y tracking coordinates directly into the signal pipeline."
        )

    @property
    def author(self) -> str: return "LabUI"

    # ── Lifecycle ─────────────────────────────────────────────────────────

    def on_load(self, context: PluginContext) -> None:
        self._ctx          = context
        self._btn          = None     # toolbar button reference
        self._windows: dict      = {}  # device_id → MotionCaptureWindow
        self._window_state: dict = {}  # device_id → {px_per_mm, camera_idx}
        from ui.add_device_dialog import _PANELS
        from camera_panel import CameraPanel
        _PANELS["Camera"] = (CameraPanel, "cam")
        from core.profile import ProfileManager
        from device import CameraDevice
        ProfileManager.register_device_factory(CameraDevice.DEVICE_TYPE, CameraDevice)

    def on_unload(self) -> None:
        for win in list(self._windows.values()):
            win.close()
        self._windows.clear()
        from ui.add_device_dialog import _PANELS
        _PANELS.pop("Camera", None)
        from core.profile import ProfileManager
        from device import CameraDevice
        ProfileManager.unregister_device_factory(CameraDevice.DEVICE_TYPE)

    # ── Integration hooks ─────────────────────────────────────────────────

    def get_toolbar_actions(self) -> list:
        return [PluginAction(
            label="Motion Capture",
            icon="🎥",
            tooltip="Open camera tracking view",
            checkable=True,
            callback=self._on_btn_toggled,
            button_ref_callback=lambda btn: setattr(self, "_btn", btn),
        )]

    def get_filter_classes(self) -> dict:
        from filter import PixelToMMFilter
        return {"pixel_to_mm": PixelToMMFilter}

    # ── Internal ──────────────────────────────────────────────────────────

    def _camera_devices(self) -> list:
        from device import CameraDevice
        return [d for d in self._ctx.registry.all_instances()
                if isinstance(d, CameraDevice)]

    def _on_btn_toggled(self, checked: bool) -> None:
        from PyQt6.QtWidgets import QInputDialog, QMessageBox
        if not checked:
            return

        cameras = self._camera_devices()

        if not cameras:
            QMessageBox.information(
                None, "No Camera Devices",
                "Add a Camera device first via Devices → Add Device.",
            )
            if self._btn is not None:
                self._btn.setChecked(False)
            return

        if len(cameras) == 1:
            self._open_window(cameras[0])
        else:
            names = [f"{d.info.name}  ({d.info.device_id})" for d in cameras]
            choice, ok = QInputDialog.getItem(
                None, "Select Camera", "Open tracking view for:", names, 0, False,
            )
            if not ok:
                if self._btn is not None:
                    self._btn.setChecked(False)
                return
            idx = names.index(choice)
            self._open_window(cameras[idx])

    def _open_window(self, device) -> None:
        from window import MotionCaptureWindow
        dev_id = device.info.device_id
        if dev_id in self._windows:
            win = self._windows[dev_id]
            win.show(); win.raise_()
            return
        if device._tracker is None:
            from PyQt6.QtWidgets import QMessageBox
            QMessageBox.warning(
                None, "Camera Not Connected",
                f"{device.info.name} is not connected. Connect it first.",
            )
            if self._btn is not None:
                self._btn.setChecked(False)
            return
        win = MotionCaptureWindow(device._tracker)

        # Restore mode/shape from live tracker state
        win.restore_ui_state(
            mode=device._tracker.track_mode,
            shape=device._tracker.template_shape,
        )
        # Restore px/mm and camera index from last session
        if dev_id in self._window_state:
            state = self._window_state[dev_id]
            win.set_px_per_mm(state["px_per_mm"])
            win.set_camera_index(state["camera_idx"])

        win.closed.connect(lambda d=dev_id, w=win: self._on_window_closed(d, w))
        self._windows[dev_id] = win
        win.show()

    def _on_window_closed(self, dev_id: str, win) -> None:
        self._window_state[dev_id] = {
            "px_per_mm":  win.get_px_per_mm(),
            "camera_idx": win.get_camera_index(),
        }
        self._windows.pop(dev_id, None)
        if not self._windows and self._btn is not None:
            self._btn.setChecked(False)